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Asterisk developer's documentation


channel.h

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00001 /*
00002  * Asterisk -- An open source telephony toolkit.
00003  *
00004  * Copyright (C) 1999 - 2006, Digium, Inc.
00005  *
00006  * Mark Spencer <markster@digium.com>
00007  *
00008  * See http://www.asterisk.org for more information about
00009  * the Asterisk project. Please do not directly contact
00010  * any of the maintainers of this project for assistance;
00011  * the project provides a web site, mailing lists and IRC
00012  * channels for your use.
00013  *
00014  * This program is free software, distributed under the terms of
00015  * the GNU General Public License Version 2. See the LICENSE file
00016  * at the top of the source tree.
00017  */
00018 
00019 /*! \file
00020  * \brief General Asterisk PBX channel definitions.
00021  * \par See also:
00022  *  \arg \ref Def_Channel
00023  *  \arg \ref channel_drivers
00024  */
00025 
00026 /*! \page Def_Channel Asterisk Channels
00027    \par What is a Channel?
00028    A phone call through Asterisk consists of an incoming
00029    connection and an outbound connection. Each call comes
00030    in through a channel driver that supports one technology,
00031    like SIP, DAHDI, IAX2 etc.
00032    \par
00033    Each channel driver, technology, has it's own private
00034    channel or dialog structure, that is technology-dependent.
00035    Each private structure is "owned" by a generic Asterisk
00036    channel structure, defined in channel.h and handled by
00037    channel.c .
00038    \par Call scenario
00039    This happens when an incoming call arrives to Asterisk
00040    -# Call arrives on a channel driver interface
00041    -# Channel driver creates a PBX channel and starts a
00042       pbx thread on the channel
00043    -# The dial plan is executed
00044    -# At this point at least two things can happen:
00045       -# The call is answered by Asterisk and
00046          Asterisk plays a media stream or reads media
00047       -# The dial plan forces Asterisk to create an outbound
00048          call somewhere with the dial (see \ref app_dial.c)
00049          application
00050    .
00051 
00052    \par Bridging channels
00053    If Asterisk dials out this happens:
00054    -# Dial creates an outbound PBX channel and asks one of the
00055       channel drivers to create a call
00056    -# When the call is answered, Asterisk bridges the media streams
00057       so the caller on the first channel can speak with the callee
00058       on the second, outbound channel
00059    -# In some cases where we have the same technology on both
00060       channels and compatible codecs, a native bridge is used.
00061       In a native bridge, the channel driver handles forwarding
00062       of incoming audio to the outbound stream internally, without
00063       sending audio frames through the PBX.
00064    -# In SIP, theres an "external native bridge" where Asterisk
00065       redirects the endpoint, so audio flows directly between the
00066       caller's phone and the callee's phone. Signalling stays in
00067       Asterisk in order to be able to provide a proper CDR record
00068       for the call.
00069 
00070 
00071    \par Masquerading channels
00072    In some cases, a channel can masquerade itself into another
00073    channel. This happens frequently in call transfers, where
00074    a new channel takes over a channel that is already involved
00075    in a call. The new channel sneaks in and takes over the bridge
00076    and the old channel, now a zombie, is hung up.
00077 
00078    \par Reference
00079    \arg channel.c - generic functions
00080    \arg channel.h - declarations of functions, flags and structures
00081    \arg translate.h - Transcoding support functions
00082    \arg \ref channel_drivers - Implemented channel drivers
00083    \arg \ref Def_Frame Asterisk Multimedia Frames
00084    \arg \ref Def_Bridge
00085 
00086 */
00087 /*! \page Def_Bridge Asterisk Channel Bridges
00088 
00089    In Asterisk, there's several media bridges.
00090 
00091    The Core bridge handles two channels (a "phone call") and bridge
00092    them together.
00093 
00094    The conference bridge (meetme) handles several channels simultaneously
00095    with the support of an external timer (DAHDI timer). This is used
00096    not only by the Conference application (meetme) but also by the
00097    page application and the SLA system introduced in 1.4.
00098    The conference bridge does not handle video.
00099 
00100    When two channels of the same type connect, the channel driver
00101    or the media subsystem used by the channel driver (i.e. RTP)
00102    can create a native bridge without sending media through the
00103    core.
00104 
00105    Native bridging can be disabled by a number of reasons,
00106    like DTMF being needed by the core or codecs being incompatible
00107    so a transcoding module is needed.
00108 
00109 References:
00110    \li \see ast_channel_early_bridge()
00111    \li \see ast_channel_bridge()
00112    \li \see app_meetme.c
00113    \li \ref AstRTPbridge
00114    \li \see ast_rtp_bridge()
00115    \li \ref Def_Channel
00116 */
00117 
00118 /*! \page AstFileDesc File descriptors
00119    Asterisk File descriptors are connected to each channel (see \ref Def_Channel)
00120    in the \ref ast_channel structure.
00121 */
00122 
00123 #ifndef _ASTERISK_CHANNEL_H
00124 #define _ASTERISK_CHANNEL_H
00125 
00126 #include "asterisk/abstract_jb.h"
00127 #include "asterisk/astobj2.h"
00128 
00129 #include "asterisk/poll-compat.h"
00130 
00131 #if defined(__cplusplus) || defined(c_plusplus)
00132 extern "C" {
00133 #endif
00134 
00135 #define AST_MAX_EXTENSION  80 /*!< Max length of an extension */
00136 #define AST_MAX_CONTEXT    80 /*!< Max length of a context */
00137 #define AST_CHANNEL_NAME   80 /*!< Max length of an ast_channel name */
00138 #define MAX_LANGUAGE    40 /*!< Max length of the language setting */
00139 #define MAX_MUSICCLASS     80 /*!< Max length of the music class setting */
00140 
00141 #include "asterisk/frame.h"
00142 #include "asterisk/sched.h"
00143 #include "asterisk/chanvars.h"
00144 #include "asterisk/config.h"
00145 #include "asterisk/lock.h"
00146 #include "asterisk/cdr.h"
00147 #include "asterisk/utils.h"
00148 #include "asterisk/linkedlists.h"
00149 #include "asterisk/stringfields.h"
00150 #include "asterisk/datastore.h"
00151 #include "asterisk/data.h"
00152 #include "asterisk/channelstate.h"
00153 #include "asterisk/ccss.h"
00154 #include "asterisk/framehook.h"
00155 
00156 #define DATASTORE_INHERIT_FOREVER   INT_MAX
00157 
00158 #define AST_MAX_FDS     10
00159 /*
00160  * We have AST_MAX_FDS file descriptors in a channel.
00161  * Some of them have a fixed use:
00162  */
00163 #define AST_ALERT_FD (AST_MAX_FDS-1)      /*!< used for alertpipe */
00164 #define AST_TIMING_FD   (AST_MAX_FDS-2)      /*!< used for timingfd */
00165 #define AST_AGENT_FD (AST_MAX_FDS-3)      /*!< used by agents for pass through */
00166 #define AST_GENERATOR_FD   (AST_MAX_FDS-4)   /*!< used by generator */
00167 
00168 enum ast_bridge_result {
00169    AST_BRIDGE_COMPLETE = 0,
00170    AST_BRIDGE_FAILED = -1,
00171    AST_BRIDGE_FAILED_NOWARN = -2,
00172    AST_BRIDGE_RETRY = -3,
00173 };
00174 
00175 typedef unsigned long long ast_group_t;
00176 
00177 /*! \todo Add an explanation of an Asterisk generator
00178 */
00179 struct ast_generator {
00180    void *(*alloc)(struct ast_channel *chan, void *params);
00181    void (*release)(struct ast_channel *chan, void *data);
00182    /*! This function gets called with the channel unlocked, but is called in
00183     *  the context of the channel thread so we know the channel is not going
00184     *  to disappear.  This callback is responsible for locking the channel as
00185     *  necessary. */
00186    int (*generate)(struct ast_channel *chan, void *data, int len, int samples);
00187    /*! This gets called when DTMF_END frames are read from the channel */
00188    void (*digit)(struct ast_channel *chan, char digit);
00189 };
00190 
00191 /*! Party name character set enumeration values (values from Q.SIG) */
00192 enum AST_PARTY_CHAR_SET {
00193    AST_PARTY_CHAR_SET_UNKNOWN = 0,
00194    AST_PARTY_CHAR_SET_ISO8859_1 = 1,
00195    AST_PARTY_CHAR_SET_WITHDRAWN = 2,/* ITU withdrew this enum value. */
00196    AST_PARTY_CHAR_SET_ISO8859_2 = 3,
00197    AST_PARTY_CHAR_SET_ISO8859_3 = 4,
00198    AST_PARTY_CHAR_SET_ISO8859_4 = 5,
00199    AST_PARTY_CHAR_SET_ISO8859_5 = 6,
00200    AST_PARTY_CHAR_SET_ISO8859_7 = 7,
00201    AST_PARTY_CHAR_SET_ISO10646_BMPSTRING = 8,
00202    AST_PARTY_CHAR_SET_ISO10646_UTF_8STRING = 9,
00203 };
00204 
00205 /*!
00206  * \since 1.8
00207  * \brief Information needed to specify a name in a call.
00208  * \note All string fields here are malloc'ed, so they need to be
00209  * freed when the structure is deleted.
00210  * \note NULL and "" must be considered equivalent.
00211  */
00212 struct ast_party_name {
00213    /*! \brief Subscriber name (Malloced) */
00214    char *str;
00215    /*!
00216     * \brief Character set the name is using.
00217     * \see enum AST_PARTY_CHAR_SET
00218     * \note
00219     * Set to AST_PARTY_CHAR_SET_ISO8859_1 if unsure what to use.
00220     * \todo Start using the party name character set value.  Not currently used.
00221     */
00222    int char_set;
00223    /*!
00224     * \brief Q.931 encoded presentation-indicator encoded field
00225     * \note Must tolerate the Q.931 screening-indicator field values being present.
00226     */
00227    int presentation;
00228    /*! \brief TRUE if the name information is valid/present */
00229    unsigned char valid;
00230 };
00231 
00232 /*!
00233  * \since 1.8
00234  * \brief Information needed to specify a number in a call.
00235  * \note All string fields here are malloc'ed, so they need to be
00236  * freed when the structure is deleted.
00237  * \note NULL and "" must be considered equivalent.
00238  */
00239 struct ast_party_number {
00240    /*! \brief Subscriber phone number (Malloced) */
00241    char *str;
00242    /*! \brief Q.931 Type-Of-Number and Numbering-Plan encoded fields */
00243    int plan;
00244    /*! \brief Q.931 presentation-indicator and screening-indicator encoded fields */
00245    int presentation;
00246    /*! \brief TRUE if the number information is valid/present */
00247    unsigned char valid;
00248 };
00249 
00250 /*!
00251  * \since 1.8
00252  * \brief Information needed to specify a subaddress in a call.
00253  * \note All string fields here are malloc'ed, so they need to be
00254  * freed when the structure is deleted.
00255  * \note NULL and "" must be considered equivalent.
00256  */
00257 struct ast_party_subaddress {
00258    /*!
00259     * \brief Malloced subaddress string.
00260     * \note If the subaddress type is user specified then the subaddress is
00261     * a string of ASCII hex because the actual subaddress is likely BCD encoded.
00262     */
00263    char *str;
00264    /*!
00265     * \brief Q.931 subaddress type.
00266     * \details
00267     * nsap(0),
00268     * user_specified(2)
00269     */
00270    int type;
00271    /*!
00272     * \brief TRUE if odd number of address signals
00273     * \note The odd/even indicator is used when the type of subaddress is
00274     * user_specified and the coding is BCD.
00275     */
00276    unsigned char odd_even_indicator;
00277    /*! \brief TRUE if the subaddress information is valid/present */
00278    unsigned char valid;
00279 };
00280 
00281 /*!
00282  * \since 1.8
00283  * \brief Information needed to identify an endpoint in a call.
00284  * \note All string fields here are malloc'ed, so they need to be
00285  * freed when the structure is deleted.
00286  * \note NULL and "" must be considered equivalent.
00287  */
00288 struct ast_party_id {
00289    /*! \brief Subscriber name */
00290    struct ast_party_name name;
00291    /*! \brief Subscriber phone number */
00292    struct ast_party_number number;
00293    /*! \brief Subscriber subaddress. */
00294    struct ast_party_subaddress subaddress;
00295 
00296    /*!
00297     * \brief User-set "tag"
00298     * \details
00299     * A user-settable field used to help associate some extrinsic information
00300     * about the channel or user of the channel to the party ID.  This information
00301     * is normally not transmitted over the wire and so is only useful within an
00302     * Asterisk environment.
00303     */
00304    char *tag;
00305 };
00306 
00307 /*!
00308  * \since 1.8
00309  * \brief Indicate what information in ast_party_id should be set.
00310  */
00311 struct ast_set_party_id {
00312    /*! TRUE if the ast_party_name information should be set. */
00313    unsigned char name;
00314    /*! TRUE if the ast_party_number information should be set. */
00315    unsigned char number;
00316    /*! TRUE if the ast_party_subaddress information should be set. */
00317    unsigned char subaddress;
00318 };
00319 
00320 /*!
00321  * \since 1.8
00322  * \brief Dialed/Called Party information.
00323  * \note Dialed Number Identifier (DNID)
00324  * \note All string fields here are malloc'ed, so they need to be
00325  * freed when the structure is deleted.
00326  * \note NULL and "" must be considered equivalent.
00327  */
00328 struct ast_party_dialed {
00329    /*!
00330     * \brief Dialed/Called number
00331     * \note Done this way in case we ever really need to use ast_party_number.
00332     * We currently do not need all of the ast_party_number fields.
00333     */
00334    struct {
00335       /*! \brief Subscriber phone number (Malloced) */
00336       char *str;
00337       /*! \brief Q.931 Type-Of-Number and Numbering-Plan encoded fields */
00338       int plan;
00339    } number;
00340    /*! \brief Dialed/Called subaddress */
00341    struct ast_party_subaddress subaddress;
00342    /*!
00343     * \brief Transit Network Select
00344     * \note Currently this value is just passed around the system.
00345     * You can read it and set it but it is never used for anything.
00346     */
00347    int transit_network_select;
00348 };
00349 
00350 /*!
00351  * \since 1.8
00352  * \brief Caller Party information.
00353  * \note All string fields here are malloc'ed, so they need to be
00354  * freed when the structure is deleted.
00355  * \note NULL and "" must be considered equivalent.
00356  *
00357  * \note SIP and IAX2 has UTF8 encoded Unicode Caller ID names.
00358  * In some cases, we also have an alternative (RPID) E.164 number that can
00359  * be used as Caller ID on numeric E.164 phone networks (DAHDI or SIP/IAX2 to
00360  * PSTN gateway).
00361  *
00362  * \todo Implement settings for transliteration between UTF8 Caller ID names in
00363  *       to ASCII Caller ID's (DAHDI). Östen Åsklund might be transliterated into
00364  *       Osten Asklund or Oesten Aasklund depending upon language and person...
00365  *       We need automatic routines for incoming calls and static settings for
00366  *       our own accounts.
00367  */
00368 struct ast_party_caller {
00369    /*! \brief Caller party ID */
00370    struct ast_party_id id;
00371 
00372    /*!
00373     * \brief Automatic Number Identification (ANI)
00374     * \note The name subcomponent is only likely to be used by SIP.
00375     * \note The subaddress subcomponent is not likely to be used.
00376     */
00377    struct ast_party_id ani;
00378 
00379    /*! \brief Automatic Number Identification 2 (Info Digits) */
00380    int ani2;
00381 };
00382 
00383 /*!
00384  * \since 1.8
00385  * \brief Indicate what information in ast_party_caller should be set.
00386  */
00387 struct ast_set_party_caller {
00388    /*! What caller id information to set. */
00389    struct ast_set_party_id id;
00390    /*! What ANI id information to set. */
00391    struct ast_set_party_id ani;
00392 };
00393 
00394 /*!
00395  * \since 1.8
00396  * \brief Connected Line/Party information.
00397  * \note All string fields here are malloc'ed, so they need to be
00398  * freed when the structure is deleted.
00399  * \note NULL and "" must be considered equivalent.
00400  */
00401 struct ast_party_connected_line {
00402    /*! \brief Connected party ID */
00403    struct ast_party_id id;
00404 
00405    /*!
00406     * \brief Automatic Number Identification (ANI)
00407     * \note Not really part of connected line data but needed to
00408     * save the corresponding caller id value.
00409     */
00410    struct ast_party_id ani;
00411 
00412    /*!
00413     * \brief Automatic Number Identification 2 (Info Digits)
00414     * \note Not really part of connected line data but needed to
00415     * save the corresponding caller id value.
00416     */
00417    int ani2;
00418 
00419    /*!
00420     * \brief Information about the source of an update.
00421     * \note enum AST_CONNECTED_LINE_UPDATE_SOURCE values
00422     * for Normal-Answer and Call-transfer.
00423     */
00424    int source;
00425 };
00426 
00427 /*!
00428  * \since 1.8
00429  * \brief Indicate what information in ast_party_connected_line should be set.
00430  */
00431 struct ast_set_party_connected_line {
00432    /*! What connected line id information to set. */
00433    struct ast_set_party_id id;
00434    /*! What ANI id information to set. */
00435    struct ast_set_party_id ani;
00436 };
00437 
00438 /*!
00439  * \since 1.8
00440  * \brief Redirecting Line information.
00441  * RDNIS (Redirecting Directory Number Information Service)
00442  * Where a call diversion or transfer was invoked.
00443  * \note All string fields here are malloc'ed, so they need to be
00444  * freed when the structure is deleted.
00445  * \note NULL and "" must be considered equivalent.
00446  */
00447 struct ast_party_redirecting {
00448    /*! \brief Who is redirecting the call (Sent to the party the call is redirected toward) */
00449    struct ast_party_id from;
00450 
00451    /*! \brief Call is redirecting to a new party (Sent to the caller) */
00452    struct ast_party_id to;
00453 
00454    /*! \brief Number of times the call was redirected */
00455    int count;
00456 
00457    /*! \brief enum AST_REDIRECTING_REASON value for redirection */
00458    int reason;
00459 };
00460 
00461 /*!
00462  * \since 1.8
00463  * \brief Indicate what information in ast_party_redirecting should be set.
00464  */
00465 struct ast_set_party_redirecting {
00466    /*! What redirecting-from id information to set. */
00467    struct ast_set_party_id from;
00468    /*! What redirecting-to id information to set. */
00469    struct ast_set_party_id to;
00470 };
00471 
00472 /*! \brief Typedef for a custom read function */
00473 typedef int (*ast_acf_read_fn_t)(struct ast_channel *, const char *, char *, char *, size_t);
00474 
00475 /*! \brief Typedef for a custom read2 function */
00476 typedef int (*ast_acf_read2_fn_t)(struct ast_channel *, const char *, char *, struct ast_str **, ssize_t);
00477 
00478 /*! \brief Typedef for a custom write function */
00479 typedef int (*ast_acf_write_fn_t)(struct ast_channel *, const char *, char *, const char *);
00480 
00481 /*! \brief Structure to handle passing func_channel_write info to channels via setoption */
00482 typedef struct {
00483    /*! \brief ast_chan_write_info_t version. Must be incremented if structure is changed */
00484    #define AST_CHAN_WRITE_INFO_T_VERSION 1
00485    uint32_t version;
00486    ast_acf_write_fn_t write_fn;
00487    struct ast_channel *chan;
00488    const char *function;
00489    char *data;
00490    const char *value;
00491 } ast_chan_write_info_t;
00492 
00493 /*!
00494  * \brief
00495  * Structure to describe a channel "technology", ie a channel driver
00496  * See for examples:
00497  * \arg chan_iax2.c - The Inter-Asterisk exchange protocol
00498  * \arg chan_sip.c - The SIP channel driver
00499  * \arg chan_dahdi.c - PSTN connectivity (TDM, PRI, T1/E1, FXO, FXS)
00500  *
00501  * \details
00502  * If you develop your own channel driver, this is where you
00503  * tell the PBX at registration of your driver what properties
00504  * this driver supports and where different callbacks are
00505  * implemented.
00506  */
00507 struct ast_channel_tech {
00508    const char * const type;
00509    const char * const description;
00510 
00511    format_t capabilities;  /*!< Bitmap of formats this channel can handle */
00512 
00513    int properties;         /*!< Technology Properties */
00514 
00515    /*!
00516     * \brief Requester - to set up call data structures (pvt's)
00517     * \note data should be treated as const char *.
00518     */
00519    struct ast_channel *(* const requester)(const char *type, format_t format, const struct ast_channel *requestor, void *data, int *cause);
00520 
00521    int (* const devicestate)(void *data); /*!< Devicestate call back */
00522 
00523    /*!
00524     * \brief Start sending a literal DTMF digit
00525     *
00526     * \note The channel is not locked when this function gets called.
00527     */
00528    int (* const send_digit_begin)(struct ast_channel *chan, char digit);
00529 
00530    /*!
00531     * \brief Stop sending a literal DTMF digit
00532     *
00533     * \note The channel is not locked when this function gets called.
00534     */
00535    int (* const send_digit_end)(struct ast_channel *chan, char digit, unsigned int duration);
00536 
00537    /*!
00538     * \brief Call a given phone number (address, etc), but don't
00539     * take longer than timeout seconds to do so.
00540     * \note addr should be treated as const char *.
00541     */
00542    int (* const call)(struct ast_channel *chan, char *addr, int timeout);
00543 
00544    /*! \brief Hangup (and possibly destroy) the channel */
00545    int (* const hangup)(struct ast_channel *chan);
00546 
00547    /*! \brief Answer the channel */
00548    int (* const answer)(struct ast_channel *chan);
00549 
00550    /*! \brief Read a frame, in standard format (see frame.h) */
00551    struct ast_frame * (* const read)(struct ast_channel *chan);
00552 
00553    /*! \brief Write a frame, in standard format (see frame.h) */
00554    int (* const write)(struct ast_channel *chan, struct ast_frame *frame);
00555 
00556    /*! \brief Display or transmit text */
00557    int (* const send_text)(struct ast_channel *chan, const char *text);
00558 
00559    /*! \brief Display or send an image */
00560    int (* const send_image)(struct ast_channel *chan, struct ast_frame *frame);
00561 
00562    /*! \brief Send HTML data */
00563    int (* const send_html)(struct ast_channel *chan, int subclass, const char *data, int len);
00564 
00565    /*! \brief Handle an exception, reading a frame */
00566    struct ast_frame * (* const exception)(struct ast_channel *chan);
00567 
00568    /*! \brief Bridge two channels of the same type together */
00569    enum ast_bridge_result (* const bridge)(struct ast_channel *c0, struct ast_channel *c1, int flags,
00570                   struct ast_frame **fo, struct ast_channel **rc, int timeoutms);
00571 
00572    /*! \brief Bridge two channels of the same type together (early) */
00573    enum ast_bridge_result (* const early_bridge)(struct ast_channel *c0, struct ast_channel *c1);
00574 
00575    /*! \brief Indicate a particular condition (e.g. AST_CONTROL_BUSY or AST_CONTROL_RINGING or AST_CONTROL_CONGESTION */
00576    int (* const indicate)(struct ast_channel *c, int condition, const void *data, size_t datalen);
00577 
00578    /*! \brief Fix up a channel:  If a channel is consumed, this is called.  Basically update any ->owner links */
00579    int (* const fixup)(struct ast_channel *oldchan, struct ast_channel *newchan);
00580 
00581    /*! \brief Set a given option. Called with chan locked */
00582    int (* const setoption)(struct ast_channel *chan, int option, void *data, int datalen);
00583 
00584    /*! \brief Query a given option. Called with chan locked */
00585    int (* const queryoption)(struct ast_channel *chan, int option, void *data, int *datalen);
00586 
00587    /*! \brief Blind transfer other side (see app_transfer.c and ast_transfer() */
00588    int (* const transfer)(struct ast_channel *chan, const char *newdest);
00589 
00590    /*! \brief Write a frame, in standard format */
00591    int (* const write_video)(struct ast_channel *chan, struct ast_frame *frame);
00592 
00593    /*! \brief Write a text frame, in standard format */
00594    int (* const write_text)(struct ast_channel *chan, struct ast_frame *frame);
00595 
00596    /*! \brief Find bridged channel */
00597    struct ast_channel *(* const bridged_channel)(struct ast_channel *chan, struct ast_channel *bridge);
00598 
00599    /*! \brief Provide additional read items for CHANNEL() dialplan function */
00600    int (* func_channel_read)(struct ast_channel *chan, const char *function, char *data, char *buf, size_t len);
00601 
00602    /*! \brief Provide additional write items for CHANNEL() dialplan function */
00603    int (* func_channel_write)(struct ast_channel *chan, const char *function, char *data, const char *value);
00604 
00605    /*! \brief Retrieve base channel (agent and local) */
00606    struct ast_channel* (* get_base_channel)(struct ast_channel *chan);
00607 
00608    /*! \brief Set base channel (agent and local) */
00609    int (* set_base_channel)(struct ast_channel *chan, struct ast_channel *base);
00610 
00611    /*! \brief Get the unique identifier for the PVT, i.e. SIP call-ID for SIP */
00612    const char * (* get_pvt_uniqueid)(struct ast_channel *chan);
00613 
00614    /*! \brief Call a function with cc parameters as a function parameter
00615     *
00616     * \details
00617     * This is a highly specialized callback that is not likely to be needed in many
00618     * channel drivers. When dealing with a busy channel, for instance, most channel
00619     * drivers will successfully return a channel to the requester. Once called, the channel
00620     * can then queue a busy frame when it receives an appropriate message from the far end.
00621     * In such a case, the channel driver has the opportunity to also queue a CC frame.
00622     * The parameters for the CC channel can be retrieved from the channel structure.
00623     *
00624     * For other channel drivers, notably those that deal with "dumb" phones, the channel
00625     * driver will not return a channel when one is requested. In such a scenario, there is never
00626     * an opportunity for the channel driver to queue a CC frame since the channel is never
00627     * called. Furthermore, it is not possible to retrieve the CC configuration parameters
00628     * for the desired channel because no channel is ever allocated or returned to the
00629     * requester. In such a case, call completion may still be a viable option. What we do is
00630     * pass the same string that the requester used originally to request the channel to the
00631     * channel driver. The channel driver can then find any potential channels/devices that
00632     * match the input and return call the designated callback with the device's call completion
00633     * parameters as a parameter.
00634     */
00635    int (* cc_callback)(struct ast_channel *inbound, const char *dest, ast_cc_callback_fn callback);
00636 };
00637 
00638 /*! Kill the channel channel driver technology descriptor. */
00639 extern const struct ast_channel_tech ast_kill_tech;
00640 
00641 struct ast_epoll_data;
00642 
00643 /*!
00644  * The high bit of the frame count is used as a debug marker, so
00645  * increments of the counters must be done with care.
00646  * Please use c->fin = FRAMECOUNT_INC(c->fin) and the same for c->fout.
00647  */
00648 #define  DEBUGCHAN_FLAG  0x80000000
00649 
00650 /* XXX not ideal to evaluate x twice... */
00651 #define  FRAMECOUNT_INC(x) ( ((x) & DEBUGCHAN_FLAG) | (((x)+1) & ~DEBUGCHAN_FLAG) )
00652 
00653 /*!
00654  * The current value of the debug flags is stored in the two
00655  * variables global_fin and global_fout (declared in main/channel.c)
00656  */
00657 extern unsigned long global_fin, global_fout;
00658 
00659 enum ast_channel_adsicpe {
00660    AST_ADSI_UNKNOWN,
00661    AST_ADSI_AVAILABLE,
00662    AST_ADSI_UNAVAILABLE,
00663    AST_ADSI_OFFHOOKONLY,
00664 };
00665 
00666 /*!
00667  * \brief Possible T38 states on channels
00668  */
00669 enum ast_t38_state {
00670    T38_STATE_UNAVAILABLE,  /*!< T38 is unavailable on this channel or disabled by configuration */
00671    T38_STATE_UNKNOWN,   /*!< The channel supports T38 but the current status is unknown */
00672    T38_STATE_NEGOTIATING,  /*!< T38 is being negotiated */
00673    T38_STATE_REJECTED,  /*!< Remote side has rejected our offer */
00674    T38_STATE_NEGOTIATED,   /*!< T38 established */
00675 };
00676 
00677 /*!
00678  * \page AstChannel ast_channel locking and reference tracking
00679  *
00680  * \par Creating Channels
00681  * A channel is allocated using the ast_channel_alloc() function.  When created, it is
00682  * automatically inserted into the main channels hash table that keeps track of all
00683  * active channels in the system.  The hash key is based on the channel name.  Because
00684  * of this, if you want to change the name, you _must_ use ast_change_name(), not change
00685  * the name field directly.  When ast_channel_alloc() returns a channel pointer, you now
00686  * hold a reference to that channel.  In most cases this reference is given to ast_pbx_run().
00687  *
00688  * \par Channel Locking
00689  * There is a lock associated with every ast_channel.  It is allocated internally via astobj2.
00690  * To lock or unlock a channel, you must use the ast_channel_lock() wrappers.
00691  *
00692  * Previously, before ast_channel was converted to astobj2, the channel lock was used in some
00693  * additional ways that are no longer necessary.  Before, the only way to ensure that a channel
00694  * did not disappear out from under you if you were working with a channel outside of the channel
00695  * thread that owns it, was to hold the channel lock.  Now, that is no longer necessary.
00696  * You simply must hold a reference to the channel to ensure it does not go away.
00697  *
00698  * The channel must be locked if you need to ensure that data that you reading from the channel
00699  * does not change while you access it.  Further, you must hold the channel lock if you are
00700  * making a non-atomic change to channel data.
00701  *
00702  * \par Channel References
00703  * There are multiple ways to get a reference to a channel.  The first is that you hold a reference
00704  * to a channel after creating it.  The other ways involve using the channel search or the channel
00705  * traversal APIs.  These functions are the ast_channel_get_*() functions or ast_channel_iterator_*()
00706  * functions.  Once a reference is retrieved by one of these methods, you know that the channel will
00707  * not go away.  So, the channel should only get locked as needed for data access or modification.
00708  * But, make sure that the reference gets released when you are done with it!
00709  *
00710  * There are different things you can do when you are done with a reference to a channel.  The first
00711  * is to simply release the reference using ast_channel_unref().  The other option is to call
00712  * ast_channel_release().  This function is generally used where ast_channel_free() was used in
00713  * the past.  The release function releases a reference as well as ensures that the channel is no
00714  * longer in the global channels container.  That way, the channel will get destroyed as soon as any
00715  * other pending references get released.
00716  *
00717  * \par Exceptions to the rules
00718  * Even though ast_channel is reference counted, there are some places where pointers to an ast_channel
00719  * get stored, but the reference count does not reflect it.  The reason is mostly historical.
00720  * The only places where this happens should be places where because of how the code works, we
00721  * _know_ that the pointer to the channel will get removed before the channel goes away.  The main
00722  * example of this is in channel drivers.  Channel drivers generally store a pointer to their owner
00723  * ast_channel in their technology specific pvt struct.  In this case, the channel drivers _know_
00724  * that this pointer to the channel will be removed in time, because the channel's hangup callback
00725  * gets called before the channel goes away.
00726  */
00727 
00728 /*!
00729  * \brief Main Channel structure associated with a channel.
00730  *
00731  * \note XXX It is important to remember to increment .cleancount each time
00732  *       this structure is changed. XXX
00733  *
00734  * \note When adding fields to this structure, it is important to add the field
00735  *       'in position' with like-aligned fields, so as to keep the compiler from
00736  *       having to add padding to align fields. The structure's fields are sorted
00737  *       in this order: pointers, structures, long, int/enum, short, char. This
00738  *       is especially important on 64-bit architectures, where mixing 4-byte
00739  *       and 8-byte fields causes 4 bytes of padding to be added before many
00740  *       8-byte fields.
00741  */
00742 struct ast_channel {
00743    const struct ast_channel_tech *tech;      /*!< Technology (point to channel driver) */
00744    void *tech_pvt;               /*!< Private data used by the technology driver */
00745    void *music_state;            /*!< Music State*/
00746    void *generatordata;          /*!< Current generator data if there is any */
00747    struct ast_generator *generator;    /*!< Current active data generator */
00748    struct ast_channel *_bridge;        /*!< Who are we bridged to, if we're bridged.
00749                       *   Who is proxying for us, if we are proxied (i.e. chan_agent).
00750                       *   Do not access directly, use ast_bridged_channel(chan) */
00751    struct ast_channel *masq;        /*!< Channel that will masquerade as us */
00752    struct ast_channel *masqr;       /*!< Who we are masquerading as */
00753    const char *blockproc;           /*!< Procedure causing blocking */
00754    const char *appl;          /*!< Current application */
00755    const char *data;          /*!< Data passed to current application */
00756    struct sched_context *sched;        /*!< Schedule context */
00757    struct ast_filestream *stream;         /*!< Stream itself. */
00758    struct ast_filestream *vstream;        /*!< Video Stream itself. */
00759    int (*timingfunc)(const void *data);
00760    void *timingdata;
00761    struct ast_pbx *pbx;          /*!< PBX private structure for this channel */
00762    struct ast_trans_pvt *writetrans;      /*!< Write translation path */
00763    struct ast_trans_pvt *readtrans;    /*!< Read translation path */
00764    struct ast_audiohook_list *audiohooks;
00765    struct ast_framehook_list *framehooks;
00766    struct ast_cdr *cdr;          /*!< Call Detail Record */
00767    struct ast_tone_zone *zone;         /*!< Tone zone as set in indications.conf or
00768                       *   in the CHANNEL dialplan function */
00769    struct ast_channel_monitor *monitor;      /*!< Channel monitoring */
00770 #ifdef HAVE_EPOLL
00771    struct ast_epoll_data *epfd_data[AST_MAX_FDS];
00772 #endif
00773 
00774    AST_DECLARE_STRING_FIELDS(
00775       AST_STRING_FIELD(name);       /*!< ASCII unique channel name */
00776       AST_STRING_FIELD(language);      /*!< Language requested for voice prompts */
00777       AST_STRING_FIELD(musicclass);    /*!< Default music class */
00778       AST_STRING_FIELD(accountcode);      /*!< Account code for billing */
00779       AST_STRING_FIELD(peeraccount);      /*!< Peer account code for billing */
00780       AST_STRING_FIELD(userfield);     /*!< Userfield for CEL billing */
00781       AST_STRING_FIELD(call_forward);     /*!< Where to forward to if asked to dial on this interface */
00782       AST_STRING_FIELD(uniqueid);      /*!< Unique Channel Identifier */
00783       AST_STRING_FIELD(linkedid);      /*!< Linked Channel Identifier -- gets propagated by linkage */
00784       AST_STRING_FIELD(parkinglot);    /*! Default parking lot, if empty, default parking lot  */
00785       AST_STRING_FIELD(hangupsource);     /*! Who is responsible for hanging up this channel */
00786       AST_STRING_FIELD(dialcontext);      /*!< Dial: Extension context that we were called from */
00787    );
00788 
00789    struct timeval whentohangup;              /*!< Non-zero, set to actual time when channel is to be hung up */
00790    pthread_t blocker;            /*!< If anyone is blocking, this is them */
00791 
00792    /*!
00793     * \brief Dialed/Called information.
00794     * \note Set on incoming channels to indicate the originally dialed party.
00795     * \note Dialed Number Identifier (DNID)
00796     */
00797    struct ast_party_dialed dialed;
00798 
00799    /*!
00800     * \brief Channel Caller ID information.
00801     * \note The caller id information is the caller id of this
00802     * channel when it is used to initiate a call.
00803     */
00804    struct ast_party_caller caller;
00805 
00806    /*!
00807     * \brief Channel Connected Line ID information.
00808     * \note The connected line information identifies the channel
00809     * connected/bridged to this channel.
00810     */
00811    struct ast_party_connected_line connected;
00812 
00813    /*! \brief Redirecting/Diversion information */
00814    struct ast_party_redirecting redirecting;
00815 
00816    struct ast_frame dtmff;          /*!< DTMF frame */
00817    struct varshead varshead;        /*!< A linked list for channel variables. See \ref AstChanVar */
00818    ast_group_t callgroup;           /*!< Call group for call pickups */
00819    ast_group_t pickupgroup;         /*!< Pickup group - which calls groups can be picked up? */
00820    AST_LIST_HEAD_NOLOCK(, ast_frame) readq;
00821    struct ast_jb jb;          /*!< The jitterbuffer state */
00822    struct timeval dtmf_tv;          /*!< The time that an in process digit began, or the last digit ended */
00823    AST_LIST_HEAD_NOLOCK(datastores, ast_datastore) datastores; /*!< Data stores on the channel */
00824    AST_LIST_HEAD_NOLOCK(autochans, ast_autochan) autochans; /*!< Autochans on the channel */
00825 
00826    unsigned long insmpl;            /*!< Track the read/written samples for monitor use */
00827    unsigned long outsmpl;           /*!< Track the read/written samples for monitor use */
00828 
00829    int fds[AST_MAX_FDS];            /*!< File descriptors for channel -- Drivers will poll on
00830                       *   these file descriptors, so at least one must be non -1.
00831                       *   See \arg \ref AstFileDesc */
00832    int _softhangup;           /*!< Whether or not we have been hung up...  Do not set this value
00833                       *   directly, use ast_softhangup() */
00834    int fdno;               /*!< Which fd had an event detected on */
00835    int streamid;              /*!< For streaming playback, the schedule ID */
00836    int vstreamid;             /*!< For streaming video playback, the schedule ID */
00837    format_t oldwriteformat;      /*!< Original writer format */
00838    int timingfd;              /*!< Timing fd */
00839    enum ast_channel_state _state;         /*!< State of line -- Don't write directly, use ast_setstate() */
00840    int rings;              /*!< Number of rings so far */
00841    int priority;              /*!< Dialplan: Current extension priority */
00842    int macropriority;            /*!< Macro: Current non-macro priority. See app_macro.c */
00843    int amaflags;              /*!< Set BEFORE PBX is started to determine AMA flags */
00844    enum ast_channel_adsicpe adsicpe;      /*!< Whether or not ADSI is detected on CPE */
00845    unsigned int fin;          /*!< Frames in counters. The high bit is a debug mask, so
00846                       *   the counter is only in the remaining bits */
00847    unsigned int fout;            /*!< Frames out counters. The high bit is a debug mask, so
00848                       *   the counter is only in the remaining bits */
00849    int hangupcause;           /*!< Why is the channel hanged up. See causes.h */
00850    unsigned int flags;           /*!< channel flags of AST_FLAG_ type */
00851    int alertpipe[2];
00852    format_t nativeformats;         /*!< Kinds of data this channel can natively handle */
00853    format_t readformat;            /*!< Requested read format (after translation) */
00854    format_t writeformat;           /*!< Requested write format (after translation) */
00855    format_t rawreadformat;         /*!< Raw read format (before translation) */
00856    format_t rawwriteformat;        /*!< Raw write format (before translation) */
00857    unsigned int emulate_dtmf_duration;    /*!< Number of ms left to emulate DTMF for */
00858 #ifdef HAVE_EPOLL
00859    int epfd;
00860 #endif
00861    int visible_indication;                         /*!< Indication currently playing on the channel */
00862 
00863    unsigned short transfercapability;     /*!< ISDN Transfer Capability - AST_FLAG_DIGITAL is not enough */
00864 
00865    struct ast_bridge *bridge;                      /*!< Bridge this channel is participating in */
00866    struct ast_timer *timer;         /*!< timer object that provided timingfd */
00867 
00868    char context[AST_MAX_CONTEXT];         /*!< Dialplan: Current extension context */
00869    char exten[AST_MAX_EXTENSION];         /*!< Dialplan: Current extension number */
00870    char macrocontext[AST_MAX_CONTEXT];    /*!< Macro: Current non-macro context. See app_macro.c */
00871    char macroexten[AST_MAX_EXTENSION];    /*!< Macro: Current non-macro extension. See app_macro.c */
00872    char emulate_dtmf_digit;         /*!< Digit being emulated */
00873 };
00874 
00875 /*! \brief ast_channel_tech Properties */
00876 enum {
00877    /*!
00878      * \brief Channels have this property if they can accept input with jitter;
00879     * i.e. most VoIP channels
00880     */
00881    AST_CHAN_TP_WANTSJITTER = (1 << 0),
00882    /*!
00883      * \brief Channels have this property if they can create jitter;
00884     * i.e. most VoIP channels
00885     */
00886    AST_CHAN_TP_CREATESJITTER = (1 << 1),
00887 };
00888 
00889 /*! \brief ast_channel flags */
00890 enum {
00891    /*! Queue incoming DTMF, to be released when this flag is turned off */
00892    AST_FLAG_DEFER_DTMF =    (1 << 1),
00893    /*! write should be interrupt generator */
00894    AST_FLAG_WRITE_INT =     (1 << 2),
00895    /*! a thread is blocking on this channel */
00896    AST_FLAG_BLOCKING =      (1 << 3),
00897    /*! This is a zombie channel */
00898    AST_FLAG_ZOMBIE =        (1 << 4),
00899    /*! There is an exception pending */
00900    AST_FLAG_EXCEPTION =     (1 << 5),
00901    /*! Listening to moh XXX anthm promises me this will disappear XXX */
00902    AST_FLAG_MOH =           (1 << 6),
00903    /*! This channel is spying on another channel */
00904    AST_FLAG_SPYING =        (1 << 7),
00905    /*! This channel is in a native bridge */
00906    AST_FLAG_NBRIDGE =       (1 << 8),
00907    /*! the channel is in an auto-incrementing dialplan processor,
00908     *  so when ->priority is set, it will get incremented before
00909     *  finding the next priority to run */
00910    AST_FLAG_IN_AUTOLOOP =   (1 << 9),
00911    /*! This is an outgoing call */
00912    AST_FLAG_OUTGOING =      (1 << 10),
00913    /*! A DTMF_BEGIN frame has been read from this channel, but not yet an END */
00914    AST_FLAG_IN_DTMF =       (1 << 12),
00915    /*! A DTMF_END was received when not IN_DTMF, so the length of the digit is
00916     *  currently being emulated */
00917    AST_FLAG_EMULATE_DTMF =  (1 << 13),
00918    /*! This is set to tell the channel not to generate DTMF begin frames, and
00919     *  to instead only generate END frames. */
00920    AST_FLAG_END_DTMF_ONLY = (1 << 14),
00921    /*! Flag to show channels that this call is hangup due to the fact that the call
00922        was indeed answered, but in another channel */
00923    AST_FLAG_ANSWERED_ELSEWHERE = (1 << 15),
00924    /*! This flag indicates that on a masquerade, an active stream should not
00925     *  be carried over */
00926    AST_FLAG_MASQ_NOSTREAM = (1 << 16),
00927    /*! This flag indicates that the hangup exten was run when the bridge terminated,
00928     *  a message aimed at preventing a subsequent hangup exten being run at the pbx_run
00929     *  level */
00930    AST_FLAG_BRIDGE_HANGUP_RUN = (1 << 17),
00931    /*! This flag indicates that the hangup exten should NOT be run when the
00932     *  bridge terminates, this will allow the hangup in the pbx loop to be run instead.
00933     *  */
00934    AST_FLAG_BRIDGE_HANGUP_DONT = (1 << 18),
00935    /*! Disable certain workarounds.  This reintroduces certain bugs, but allows
00936     *  some non-traditional dialplans (like AGI) to continue to function.
00937     */
00938    AST_FLAG_DISABLE_WORKAROUNDS = (1 << 20),
00939 };
00940 
00941 /*! \brief ast_bridge_config flags */
00942 enum {
00943    AST_FEATURE_PLAY_WARNING = (1 << 0),
00944    AST_FEATURE_REDIRECT =     (1 << 1),
00945    AST_FEATURE_DISCONNECT =   (1 << 2),
00946    AST_FEATURE_ATXFER =       (1 << 3),
00947    AST_FEATURE_AUTOMON =      (1 << 4),
00948    AST_FEATURE_PARKCALL =     (1 << 5),
00949    AST_FEATURE_AUTOMIXMON =   (1 << 6),
00950    AST_FEATURE_NO_H_EXTEN =   (1 << 7),
00951    AST_FEATURE_WARNING_ACTIVE = (1 << 8),
00952 };
00953 
00954 /*! \brief bridge configuration */
00955 struct ast_bridge_config {
00956    struct ast_flags features_caller;
00957    struct ast_flags features_callee;
00958    struct timeval start_time;
00959    struct timeval nexteventts;
00960    struct timeval feature_start_time;
00961    long feature_timer;
00962    long timelimit;
00963    long play_warning;
00964    long warning_freq;
00965    const char *warning_sound;
00966    const char *end_sound;
00967    const char *start_sound;
00968    unsigned int flags;
00969    void (* end_bridge_callback)(void *);   /*!< A callback that is called after a bridge attempt */
00970    void *end_bridge_callback_data;         /*!< Data passed to the callback */
00971    /*! If the end_bridge_callback_data refers to a channel which no longer is going to
00972     * exist when the end_bridge_callback is called, then it needs to be fixed up properly
00973     */
00974    void (*end_bridge_callback_data_fixup)(struct ast_bridge_config *bconfig, struct ast_channel *originator, struct ast_channel *terminator);
00975 };
00976 
00977 struct chanmon;
00978 
00979 struct outgoing_helper {
00980    const char *context;
00981    const char *exten;
00982    int priority;
00983    const char *cid_num;
00984    const char *cid_name;
00985    const char *account;
00986    struct ast_variable *vars;
00987    struct ast_channel *parent_channel;
00988 };
00989 
00990 enum {
00991    /*!
00992     * Soft hangup requested by device or other internal reason.
00993     * Actual hangup needed.
00994     */
00995    AST_SOFTHANGUP_DEV =       (1 << 0),
00996    /*!
00997     * Used to break the normal frame flow so an async goto can be
00998     * done instead of actually hanging up.
00999     */
01000    AST_SOFTHANGUP_ASYNCGOTO = (1 << 1),
01001    /*!
01002     * Soft hangup requested by system shutdown.  Actual hangup
01003     * needed.
01004     */
01005    AST_SOFTHANGUP_SHUTDOWN =  (1 << 2),
01006    /*!
01007     * Used to break the normal frame flow after a timeout so an
01008     * implicit async goto can be done to the 'T' exten if it exists
01009     * instead of actually hanging up.  If the exten does not exist
01010     * then actually hangup.
01011     */
01012    AST_SOFTHANGUP_TIMEOUT =   (1 << 3),
01013    /*!
01014     * Soft hangup requested by application/channel-driver being
01015     * unloaded.  Actual hangup needed.
01016     */
01017    AST_SOFTHANGUP_APPUNLOAD = (1 << 4),
01018    /*!
01019     * Soft hangup requested by non-associated party.  Actual hangup
01020     * needed.
01021     */
01022    AST_SOFTHANGUP_EXPLICIT =  (1 << 5),
01023    /*!
01024     * Used to break a bridge so the channel can be spied upon
01025     * instead of actually hanging up.
01026     */
01027    AST_SOFTHANGUP_UNBRIDGE =  (1 << 6),
01028 
01029 
01030    /*!
01031     * \brief All softhangup flags.
01032     *
01033     * This can be used as an argument to ast_channel_softhangup_clear
01034     * to clear all softhangup flags from a channel.
01035     */
01036    AST_SOFTHANGUP_ALL =       (0xFFFFFFFF)
01037 };
01038 
01039 
01040 /*! \brief Channel reload reasons for manager events at load or reload of configuration */
01041 enum channelreloadreason {
01042    CHANNEL_MODULE_LOAD,
01043    CHANNEL_MODULE_RELOAD,
01044    CHANNEL_CLI_RELOAD,
01045    CHANNEL_MANAGER_RELOAD,
01046 };
01047 
01048 /*!
01049  * \note None of the datastore API calls lock the ast_channel they are using.
01050  *       So, the channel should be locked before calling the functions that
01051  *       take a channel argument.
01052  */
01053 
01054 /*!
01055  * \brief Create a channel data store object
01056  * \deprecated You should use the ast_datastore_alloc() generic function instead.
01057  * \version 1.6.1 deprecated
01058  */
01059 struct ast_datastore * attribute_malloc ast_channel_datastore_alloc(const struct ast_datastore_info *info, const char *uid)
01060    __attribute__((deprecated));
01061 
01062 /*!
01063  * \brief Free a channel data store object
01064  * \deprecated You should use the ast_datastore_free() generic function instead.
01065  * \version 1.6.1 deprecated
01066  */
01067 int ast_channel_datastore_free(struct ast_datastore *datastore)
01068    __attribute__((deprecated));
01069 
01070 /*! \brief Inherit datastores from a parent to a child. */
01071 int ast_channel_datastore_inherit(struct ast_channel *from, struct ast_channel *to);
01072 
01073 /*!
01074  * \brief Add a datastore to a channel
01075  *
01076  * \note The channel should be locked before calling this function.
01077  *
01078  * \retval 0 success
01079  * \retval non-zero failure
01080  */
01081 int ast_channel_datastore_add(struct ast_channel *chan, struct ast_datastore *datastore);
01082 
01083 /*!
01084  * \brief Remove a datastore from a channel
01085  *
01086  * \note The channel should be locked before calling this function.
01087  *
01088  * \retval 0 success
01089  * \retval non-zero failure
01090  */
01091 int ast_channel_datastore_remove(struct ast_channel *chan, struct ast_datastore *datastore);
01092 
01093 /*!
01094  * \brief Find a datastore on a channel
01095  *
01096  * \note The channel should be locked before calling this function.
01097  *
01098  * \note The datastore returned from this function must not be used if the
01099  *       reference to the channel is released.
01100  *
01101  * \retval pointer to the datastore if found
01102  * \retval NULL if not found
01103  */
01104 struct ast_datastore *ast_channel_datastore_find(struct ast_channel *chan, const struct ast_datastore_info *info, const char *uid);
01105 
01106 /*!
01107  * \brief Create a channel structure
01108  * \since 1.8
01109  *
01110  * \retval NULL failure
01111  * \retval non-NULL successfully allocated channel
01112  *
01113  * \note Absolutely _NO_ channel locks should be held before calling this function.
01114  * \note By default, new channels are set to the "s" extension
01115  *       and "default" context.
01116  */
01117 struct ast_channel * attribute_malloc __attribute__((format(printf, 13, 14)))
01118    __ast_channel_alloc(int needqueue, int state, const char *cid_num,
01119              const char *cid_name, const char *acctcode,
01120              const char *exten, const char *context,
01121              const char *linkedid, const int amaflag,
01122              const char *file, int line, const char *function,
01123              const char *name_fmt, ...);
01124 
01125 /*!
01126  * \brief Create a channel structure
01127  *
01128  * \retval NULL failure
01129  * \retval non-NULL successfully allocated channel
01130  *
01131  * \note Absolutely _NO_ channel locks should be held before calling this function.
01132  * \note By default, new channels are set to the "s" extension
01133  *       and "default" context.
01134  */
01135 #define ast_channel_alloc(needqueue, state, cid_num, cid_name, acctcode, exten, context, linkedid, amaflag, ...) \
01136    __ast_channel_alloc(needqueue, state, cid_num, cid_name, acctcode, exten, context, linkedid, amaflag, \
01137              __FILE__, __LINE__, __FUNCTION__, __VA_ARGS__)
01138 
01139 #if defined(REF_DEBUG) || defined(__AST_DEBUG_MALLOC)
01140 /*!
01141  * \brief Create a fake channel structure
01142  *
01143  * \retval NULL failure
01144  * \retval non-NULL successfully allocated channel
01145  *
01146  * \note This function should ONLY be used to create a fake channel
01147  *       that can then be populated with data for use in variable
01148  *       substitution when a real channel does not exist.
01149  *
01150  * \note The created dummy channel should be destroyed by
01151  * ast_channel_unref().  Using ast_channel_release() needlessly
01152  * grabs the channel container lock and can cause a deadlock as
01153  * a result.  Also grabbing the channel container lock reduces
01154  * system performance.
01155  */
01156 #define ast_dummy_channel_alloc()   __ast_dummy_channel_alloc(__FILE__, __LINE__, __PRETTY_FUNCTION__)
01157 struct ast_channel *__ast_dummy_channel_alloc(const char *file, int line, const char *function);
01158 #else
01159 /*!
01160  * \brief Create a fake channel structure
01161  *
01162  * \retval NULL failure
01163  * \retval non-NULL successfully allocated channel
01164  *
01165  * \note This function should ONLY be used to create a fake channel
01166  *       that can then be populated with data for use in variable
01167  *       substitution when a real channel does not exist.
01168  *
01169  * \note The created dummy channel should be destroyed by
01170  * ast_channel_unref().  Using ast_channel_release() needlessly
01171  * grabs the channel container lock and can cause a deadlock as
01172  * a result.  Also grabbing the channel container lock reduces
01173  * system performance.
01174  */
01175 struct ast_channel *ast_dummy_channel_alloc(void);
01176 #endif
01177 
01178 /*!
01179  * \brief Queue one or more frames to a channel's frame queue
01180  *
01181  * \param chan the channel to queue the frame(s) on
01182  * \param f the frame(s) to queue.  Note that the frame(s) will be duplicated
01183  *        by this function.  It is the responsibility of the caller to handle
01184  *        freeing the memory associated with the frame(s) being passed if
01185  *        necessary.
01186  *
01187  * \retval 0 success
01188  * \retval non-zero failure
01189  */
01190 int ast_queue_frame(struct ast_channel *chan, struct ast_frame *f);
01191 
01192 /*!
01193  * \brief Queue one or more frames to the head of a channel's frame queue
01194  *
01195  * \param chan the channel to queue the frame(s) on
01196  * \param f the frame(s) to queue.  Note that the frame(s) will be duplicated
01197  *        by this function.  It is the responsibility of the caller to handle
01198  *        freeing the memory associated with the frame(s) being passed if
01199  *        necessary.
01200  *
01201  * \retval 0 success
01202  * \retval non-zero failure
01203  */
01204 int ast_queue_frame_head(struct ast_channel *chan, struct ast_frame *f);
01205 
01206 /*!
01207  * \brief Queue a hangup frame
01208  *
01209  * \note The channel does not need to be locked before calling this function.
01210  */
01211 int ast_queue_hangup(struct ast_channel *chan);
01212 
01213 /*!
01214  * \brief Queue a hangup frame with hangupcause set
01215  *
01216  * \note The channel does not need to be locked before calling this function.
01217  * \param[in] chan channel to queue frame onto
01218  * \param[in] cause the hangup cause
01219  * \return 0 on success, -1 on error
01220  * \since 1.6.1
01221  */
01222 int ast_queue_hangup_with_cause(struct ast_channel *chan, int cause);
01223 
01224 /*!
01225  * \brief Queue a control frame with payload
01226  *
01227  * \param chan channel to queue frame onto
01228  * \param control type of control frame
01229  *
01230  * \note The channel does not need to be locked before calling this function.
01231  *
01232  * \retval zero on success
01233  * \retval non-zero on failure
01234  */
01235 int ast_queue_control(struct ast_channel *chan, enum ast_control_frame_type control);
01236 
01237 /*!
01238  * \brief Queue a control frame with payload
01239  *
01240  * \param chan channel to queue frame onto
01241  * \param control type of control frame
01242  * \param data pointer to payload data to be included in frame
01243  * \param datalen number of bytes of payload data
01244  *
01245  * \retval 0 success
01246  * \retval non-zero failure
01247  *
01248  * \details
01249  * The supplied payload data is copied into the frame, so the caller's copy
01250  * is not modified nor freed, and the resulting frame will retain a copy of
01251  * the data even if the caller frees their local copy.
01252  *
01253  * \note This method should be treated as a 'network transport'; in other
01254  * words, your frames may be transferred across an IAX2 channel to another
01255  * system, which may be a different endianness than yours. Because of this,
01256  * you should ensure that either your frames will never be expected to work
01257  * across systems, or that you always put your payload data into 'network byte
01258  * order' before calling this function.
01259  *
01260  * \note The channel does not need to be locked before calling this function.
01261  */
01262 int ast_queue_control_data(struct ast_channel *chan, enum ast_control_frame_type control,
01263             const void *data, size_t datalen);
01264 
01265 /*!
01266  * \brief Change channel name
01267  *
01268  * \pre Absolutely all channels _MUST_ be unlocked before calling this function.
01269  *
01270  * \param chan the channel to change the name of
01271  * \param newname the name to change to
01272  *
01273  * \return nothing
01274  *
01275  * \note this function must _NEVER_ be used when any channels are locked
01276  * regardless if it is the channel who's name is being changed or not because
01277  * it invalidates our channel container locking order... lock container first,
01278  * then the individual channels, never the other way around.
01279  */
01280 void ast_change_name(struct ast_channel *chan, const char *newname);
01281 
01282 /*!
01283  * \brief Unlink and release reference to a channel
01284  *
01285  * This function will unlink the channel from the global channels container
01286  * if it is still there and also release the current reference to the channel.
01287  *
01288  * \return NULL, convenient for clearing invalid pointers
01289  * \note Absolutely _NO_ channel locks should be held before calling this function.
01290  *
01291  * \since 1.8
01292  */
01293 struct ast_channel *ast_channel_release(struct ast_channel *chan);
01294 
01295 /*!
01296  * \brief Requests a channel
01297  *
01298  * \param type type of channel to request
01299  * \param format requested channel format (codec)
01300  * \param requestor channel asking for data
01301  * \param data data to pass to the channel requester (Should be treated as const char *)
01302  * \param status status
01303  *
01304  * \details
01305  * Request a channel of a given type, with data as optional information used
01306  * by the low level module
01307  *
01308  * \retval NULL failure
01309  * \retval non-NULL channel on success
01310  */
01311 struct ast_channel *ast_request(const char *type, format_t format, const struct ast_channel *requestor, void *data, int *status);
01312 
01313 /*!
01314  * \brief Request a channel of a given type, with data as optional information used
01315  *        by the low level module and attempt to place a call on it
01316  *
01317  * \param type type of channel to request
01318  * \param format requested channel format
01319  * \param requestor channel asking for data
01320  * \param data data to pass to the channel requester
01321  * \param timeout maximum amount of time to wait for an answer
01322  * \param reason why unsuccessful (if unsuccessful)
01323  * \param cid_num Caller-ID Number
01324  * \param cid_name Caller-ID Name (ascii)
01325  *
01326  * \return Returns an ast_channel on success or no answer, NULL on failure.  Check the value of chan->_state
01327  * to know if the call was answered or not.
01328  */
01329 struct ast_channel *ast_request_and_dial(const char *type, format_t format, const struct ast_channel *requestor, void *data,
01330    int timeout, int *reason, const char *cid_num, const char *cid_name);
01331 
01332 /*!
01333  * \brief Request a channel of a given type, with data as optional information used
01334  * by the low level module and attempt to place a call on it
01335  * \param type type of channel to request
01336  * \param format requested channel format
01337  * \param requestor channel requesting data
01338  * \param data data to pass to the channel requester
01339  * \param timeout maximum amount of time to wait for an answer
01340  * \param reason why unsuccessful (if unsuccessful)
01341  * \param cid_num Caller-ID Number
01342  * \param cid_name Caller-ID Name (ascii)
01343  * \param oh Outgoing helper
01344  * \return Returns an ast_channel on success or no answer, NULL on failure.  Check the value of chan->_state
01345  * to know if the call was answered or not.
01346  */
01347 struct ast_channel *__ast_request_and_dial(const char *type, format_t format, const struct ast_channel *requestor, void *data,
01348    int timeout, int *reason, const char *cid_num, const char *cid_name, struct outgoing_helper *oh);
01349 
01350 /*!
01351  * \brief Forwards a call to a new channel specified by the original channel's call_forward str.  If possible, the new forwarded channel is created and returned while the original one is terminated.
01352  * \param caller in channel that requested orig
01353  * \param orig channel being replaced by the call forward channel
01354  * \param timeout maximum amount of time to wait for setup of new forward channel
01355  * \param format requested channel format
01356  * \param oh outgoing helper used with original channel
01357  * \param outstate reason why unsuccessful (if uncuccessful)
01358  * \return Returns the forwarded call's ast_channel on success or NULL on failure
01359  */
01360 struct ast_channel *ast_call_forward(struct ast_channel *caller, struct ast_channel *orig, int *timeout, format_t format, struct outgoing_helper *oh, int *outstate);
01361 
01362 /*!
01363  * \brief Register a channel technology (a new channel driver)
01364  * Called by a channel module to register the kind of channels it supports.
01365  * \param tech Structure defining channel technology or "type"
01366  * \return Returns 0 on success, -1 on failure.
01367  */
01368 int ast_channel_register(const struct ast_channel_tech *tech);
01369 
01370 /*!
01371  * \brief Unregister a channel technology
01372  * \param tech Structure defining channel technology or "type" that was previously registered
01373  * \return No return value.
01374  */
01375 void ast_channel_unregister(const struct ast_channel_tech *tech);
01376 
01377 /*!
01378  * \brief Get a channel technology structure by name
01379  * \param name name of technology to find
01380  * \return a pointer to the structure, or NULL if no matching technology found
01381  */
01382 const struct ast_channel_tech *ast_get_channel_tech(const char *name);
01383 
01384 #ifdef CHANNEL_TRACE
01385 /*!
01386  * \brief Update the context backtrace if tracing is enabled
01387  * \return Returns 0 on success, -1 on failure
01388  */
01389 int ast_channel_trace_update(struct ast_channel *chan);
01390 
01391 /*!
01392  * \brief Enable context tracing in the channel
01393  * \return Returns 0 on success, -1 on failure
01394  */
01395 int ast_channel_trace_enable(struct ast_channel *chan);
01396 
01397 /*!
01398  * \brief Disable context tracing in the channel.
01399  * \note Does not remove current trace entries
01400  * \return Returns 0 on success, -1 on failure
01401  */
01402 int ast_channel_trace_disable(struct ast_channel *chan);
01403 
01404 /*!
01405  * \brief Whether or not context tracing is enabled
01406  * \return Returns -1 when the trace is enabled. 0 if not.
01407  */
01408 int ast_channel_trace_is_enabled(struct ast_channel *chan);
01409 
01410 /*!
01411  * \brief Put the channel backtrace in a string
01412  * \return Returns the amount of lines in the backtrace. -1 on error.
01413  */
01414 int ast_channel_trace_serialize(struct ast_channel *chan, struct ast_str **out);
01415 #endif
01416 
01417 /*!
01418  * \brief Hang up a channel
01419  * \note Absolutely _NO_ channel locks should be held before calling this function.
01420  * \note This function performs a hard hangup on a channel.  Unlike the soft-hangup, this function
01421  * performs all stream stopping, etc, on the channel that needs to end.
01422  * chan is no longer valid after this call.
01423  * \param chan channel to hang up
01424  * \return Returns 0 on success, -1 on failure.
01425  */
01426 int ast_hangup(struct ast_channel *chan);
01427 
01428 /*!
01429  * \brief Softly hangup up a channel
01430  *
01431  * \param chan channel to be soft-hung-up
01432  * \param reason an AST_SOFTHANGUP_* reason code
01433  *
01434  * \details
01435  * Call the protocol layer, but don't destroy the channel structure
01436  * (use this if you are trying to
01437  * safely hangup a channel managed by another thread.
01438  *
01439  * \note The channel passed to this function does not need to be locked.
01440  *
01441  * \return Returns 0 regardless
01442  */
01443 int ast_softhangup(struct ast_channel *chan, int reason);
01444 
01445 /*!
01446  * \brief Softly hangup up a channel (no channel lock)
01447  * \param chan channel to be soft-hung-up
01448  * \param reason an AST_SOFTHANGUP_* reason code
01449  */
01450 int ast_softhangup_nolock(struct ast_channel *chan, int reason);
01451 
01452 /*!
01453  * \brief Clear a set of softhangup flags from a channel
01454  *
01455  * Never clear a softhangup flag from a channel directly.  Instead,
01456  * use this function.  This ensures that all aspects of the softhangup
01457  * process are aborted.
01458  *
01459  * \param chan the channel to clear the flag on
01460  * \param flag the flag or flags to clear
01461  *
01462  * \return Nothing.
01463  */
01464 void ast_channel_clear_softhangup(struct ast_channel *chan, int flag);
01465 
01466 /*!
01467  * \brief Set the source of the hangup in this channel and it's bridge
01468  *
01469  * \param chan channel to set the field on
01470  * \param source a string describing the source of the hangup for this channel
01471  * \param force
01472  *
01473  * \note Absolutely _NO_ channel locks should be held before calling this function.
01474  *
01475  * \since 1.8
01476  *
01477  * Hangupsource is generally the channel name that caused the bridge to be
01478  * hung up, but it can also be other things such as "dialplan/agi"
01479  * This can then be logged in the CDR or CEL
01480  */
01481 void ast_set_hangupsource(struct ast_channel *chan, const char *source, int force);
01482 
01483 /*! \brief Check to see if a channel is needing hang up
01484  * \param chan channel on which to check for hang up
01485  * This function determines if the channel is being requested to be hung up.
01486  * \return Returns 0 if not, or 1 if hang up is requested (including time-out).
01487  */
01488 int ast_check_hangup(struct ast_channel *chan);
01489 
01490 int ast_check_hangup_locked(struct ast_channel *chan);
01491 
01492 /*!
01493  * \brief Compare a offset with the settings of when to hang a channel up
01494  * \param chan channel on which to check for hang up
01495  * \param offset offset in seconds from current time
01496  * \return 1, 0, or -1
01497  * \details
01498  * This function compares a offset from current time with the absolute time
01499  * out on a channel (when to hang up). If the absolute time out on a channel
01500  * is earlier than current time plus the offset, it returns 1, if the two
01501  * time values are equal, it return 0, otherwise, it return -1.
01502  * \sa ast_channel_cmpwhentohangup_tv()
01503  * \version 1.6.1 deprecated function (only had seconds precision)
01504  */
01505 int ast_channel_cmpwhentohangup(struct ast_channel *chan, time_t offset) __attribute__((deprecated));
01506 
01507 /*!
01508  * \brief Compare a offset with the settings of when to hang a channel up
01509  * \param chan channel on which to check for hangup
01510  * \param offset offset in seconds and microseconds from current time
01511  * \return 1, 0, or -1
01512  * This function compares a offset from current time with the absolute time
01513  * out on a channel (when to hang up). If the absolute time out on a channel
01514  * is earlier than current time plus the offset, it returns 1, if the two
01515  * time values are equal, it return 0, otherwise, it return -1.
01516  * \since 1.6.1
01517  */
01518 int ast_channel_cmpwhentohangup_tv(struct ast_channel *chan, struct timeval offset);
01519 
01520 /*!
01521  * \brief Set when to hang a channel up
01522  *
01523  * \param chan channel on which to check for hang up
01524  * \param offset offset in seconds relative to the current time of when to hang up
01525  *
01526  * \details
01527  * This function sets the absolute time out on a channel (when to hang up).
01528  *
01529  * \note This function does not require that the channel is locked before
01530  *       calling it.
01531  *
01532  * \return Nothing
01533  * \sa ast_channel_setwhentohangup_tv()
01534  * \version 1.6.1 deprecated function (only had seconds precision)
01535  */
01536 void ast_channel_setwhentohangup(struct ast_channel *chan, time_t offset) __attribute__((deprecated));
01537 
01538 /*!
01539  * \brief Set when to hang a channel up
01540  *
01541  * \param chan channel on which to check for hang up
01542  * \param offset offset in seconds and useconds relative to the current time of when to hang up
01543  *
01544  * This function sets the absolute time out on a channel (when to hang up).
01545  *
01546  * \note This function does not require that the channel is locked before
01547  * calling it.
01548  *
01549  * \return Nothing
01550  * \since 1.6.1
01551  */
01552 void ast_channel_setwhentohangup_tv(struct ast_channel *chan, struct timeval offset);
01553 
01554 /*!
01555  * \brief Answer a channel
01556  *
01557  * \param chan channel to answer
01558  *
01559  * \details
01560  * This function answers a channel and handles all necessary call
01561  * setup functions.
01562  *
01563  * \note The channel passed does not need to be locked, but is locked
01564  * by the function when needed.
01565  *
01566  * \note This function will wait up to 500 milliseconds for media to
01567  * arrive on the channel before returning to the caller, so that the
01568  * caller can properly assume the channel is 'ready' for media flow.
01569  *
01570  * \retval 0 on success
01571  * \retval non-zero on failure
01572  */
01573 int ast_answer(struct ast_channel *chan);
01574 
01575 /*!
01576  * \brief Answer a channel
01577  *
01578  * \param chan channel to answer
01579  * \param cdr_answer flag to control whether any associated CDR should be marked as 'answered'
01580  *
01581  * This function answers a channel and handles all necessary call
01582  * setup functions.
01583  *
01584  * \note The channel passed does not need to be locked, but is locked
01585  * by the function when needed.
01586  *
01587  * \note Unlike ast_answer(), this function will not wait for media
01588  * flow to begin. The caller should be careful before sending media
01589  * to the channel before incoming media arrives, as the outgoing
01590  * media may be lost.
01591  *
01592  * \retval 0 on success
01593  * \retval non-zero on failure
01594  */
01595 int ast_raw_answer(struct ast_channel *chan, int cdr_answer);
01596 
01597 /*!
01598  * \brief Answer a channel, with a selectable delay before returning
01599  *
01600  * \param chan channel to answer
01601  * \param delay maximum amount of time to wait for incoming media
01602  * \param cdr_answer flag to control whether any associated CDR should be marked as 'answered'
01603  *
01604  * This function answers a channel and handles all necessary call
01605  * setup functions.
01606  *
01607  * \note The channel passed does not need to be locked, but is locked
01608  * by the function when needed.
01609  *
01610  * \note This function will wait up to 'delay' milliseconds for media to
01611  * arrive on the channel before returning to the caller, so that the
01612  * caller can properly assume the channel is 'ready' for media flow. If
01613  * 'delay' is less than 500, the function will wait up to 500 milliseconds.
01614  *
01615  * \retval 0 on success
01616  * \retval non-zero on failure
01617  */
01618 int __ast_answer(struct ast_channel *chan, unsigned int delay, int cdr_answer);
01619 
01620 /*!
01621  * \brief Make a call
01622  * \note Absolutely _NO_ channel locks should be held before calling this function.
01623  * \param chan which channel to make the call on
01624  * \param addr destination of the call (Should be treated as const char *)
01625  * \param timeout time to wait on for connect
01626  * \details
01627  * Place a call, take no longer than timeout ms.
01628  * \return -1 on failure, 0 on not enough time
01629  * (does not automatically stop ringing), and
01630  * the number of seconds the connect took otherwise.
01631  */
01632 int ast_call(struct ast_channel *chan, char *addr, int timeout);
01633 
01634 /*!
01635  * \brief Indicates condition of channel
01636  * \note Absolutely _NO_ channel locks should be held before calling this function.
01637  * \note Indicate a condition such as AST_CONTROL_BUSY, AST_CONTROL_RINGING, or AST_CONTROL_CONGESTION on a channel
01638  * \param chan channel to change the indication
01639  * \param condition which condition to indicate on the channel
01640  * \return Returns 0 on success, -1 on failure
01641  */
01642 int ast_indicate(struct ast_channel *chan, int condition);
01643 
01644 /*!
01645  * \brief Indicates condition of channel, with payload
01646  * \note Absolutely _NO_ channel locks should be held before calling this function.
01647  * \note Indicate a condition such as AST_CONTROL_HOLD with payload being music on hold class
01648  * \param chan channel to change the indication
01649  * \param condition which condition to indicate on the channel
01650  * \param data pointer to payload data
01651  * \param datalen size of payload data
01652  * \return Returns 0 on success, -1 on failure
01653  */
01654 int ast_indicate_data(struct ast_channel *chan, int condition, const void *data, size_t datalen);
01655 
01656 /* Misc stuff ------------------------------------------------ */
01657 
01658 /*!
01659  * \brief Wait for input on a channel
01660  * \param chan channel to wait on
01661  * \param ms length of time to wait on the channel
01662  * \details
01663  * Wait for input on a channel for a given # of milliseconds (<0 for indefinite).
01664  * \retval < 0 on failure
01665  * \retval 0 if nothing ever arrived
01666  * \retval the # of ms remaining otherwise
01667  */
01668 int ast_waitfor(struct ast_channel *chan, int ms);
01669 
01670 /*!
01671  * \brief Should we keep this frame for later?
01672  *
01673  * There are functions such as ast_safe_sleep which will
01674  * service a channel to ensure that it does not have a
01675  * large backlog of queued frames. When this happens,
01676  * we want to hold on to specific frame types and just drop
01677  * others. This function will tell if the frame we just
01678  * read should be held onto.
01679  *
01680  * \param frame The frame we just read
01681  * \retval 1 frame should be kept
01682  * \retval 0 frame should be dropped
01683  */
01684 int ast_is_deferrable_frame(const struct ast_frame *frame);
01685 
01686 /*!
01687  * \brief Wait for a specified amount of time, looking for hangups
01688  * \param chan channel to wait for
01689  * \param ms length of time in milliseconds to sleep
01690  * \details
01691  * Waits for a specified amount of time, servicing the channel as required.
01692  * \return returns -1 on hangup, otherwise 0.
01693  */
01694 int ast_safe_sleep(struct ast_channel *chan, int ms);
01695 
01696 /*!
01697  * \brief Wait for a specified amount of time, looking for hangups and a condition argument
01698  * \param chan channel to wait for
01699  * \param ms length of time in milliseconds to sleep
01700  * \param cond a function pointer for testing continue condition
01701  * \param data argument to be passed to the condition test function
01702  * \return returns -1 on hangup, otherwise 0.
01703  * \details
01704  * Waits for a specified amount of time, servicing the channel as required. If cond
01705  * returns 0, this function returns.
01706  */
01707 int ast_safe_sleep_conditional(struct ast_channel *chan, int ms, int (*cond)(void*), void *data );
01708 
01709 /*!
01710  * \brief Waits for activity on a group of channels
01711  * \param chan an array of pointers to channels
01712  * \param n number of channels that are to be waited upon
01713  * \param fds an array of fds to wait upon
01714  * \param nfds the number of fds to wait upon
01715  * \param exception exception flag
01716  * \param outfd fd that had activity on it
01717  * \param ms how long the wait was
01718  * \details
01719  * Big momma function here.  Wait for activity on any of the n channels, or any of the nfds
01720  * file descriptors.
01721  * \return Returns the channel with activity, or NULL on error or if an FD
01722  * came first.  If the FD came first, it will be returned in outfd, otherwise, outfd
01723  * will be -1
01724  */
01725 struct ast_channel *ast_waitfor_nandfds(struct ast_channel **chan, int n,
01726    int *fds, int nfds, int *exception, int *outfd, int *ms);
01727 
01728 /*!
01729  * \brief Waits for input on a group of channels
01730  * Wait for input on an array of channels for a given # of milliseconds.
01731  * \return Return channel with activity, or NULL if none has activity.
01732  * \param chan an array of pointers to channels
01733  * \param n number of channels that are to be waited upon
01734  * \param ms time "ms" is modified in-place, if applicable
01735  */
01736 struct ast_channel *ast_waitfor_n(struct ast_channel **chan, int n, int *ms);
01737 
01738 /*!
01739  * \brief Waits for input on an fd
01740  * \note This version works on fd's only.  Be careful with it.
01741  */
01742 int ast_waitfor_n_fd(int *fds, int n, int *ms, int *exception);
01743 
01744 
01745 /*!
01746  * \brief Reads a frame
01747  * \param chan channel to read a frame from
01748  * \return Returns a frame, or NULL on error.  If it returns NULL, you
01749  * best just stop reading frames and assume the channel has been
01750  * disconnected.
01751  */
01752 struct ast_frame *ast_read(struct ast_channel *chan);
01753 
01754 /*!
01755  * \brief Reads a frame, returning AST_FRAME_NULL frame if audio.
01756  * \param chan channel to read a frame from
01757  * \return  Returns a frame, or NULL on error.  If it returns NULL, you
01758  * best just stop reading frames and assume the channel has been
01759  * disconnected.
01760  * \note Audio is replaced with AST_FRAME_NULL to avoid
01761  * transcode when the resulting audio is not necessary.
01762  */
01763 struct ast_frame *ast_read_noaudio(struct ast_channel *chan);
01764 
01765 /*!
01766  * \brief Write a frame to a channel
01767  * This function writes the given frame to the indicated channel.
01768  * \param chan destination channel of the frame
01769  * \param frame frame that will be written
01770  * \return It returns 0 on success, -1 on failure.
01771  */
01772 int ast_write(struct ast_channel *chan, struct ast_frame *frame);
01773 
01774 /*!
01775  * \brief Write video frame to a channel
01776  * This function writes the given frame to the indicated channel.
01777  * \param chan destination channel of the frame
01778  * \param frame frame that will be written
01779  * \return It returns 1 on success, 0 if not implemented, and -1 on failure.
01780  */
01781 int ast_write_video(struct ast_channel *chan, struct ast_frame *frame);
01782 
01783 /*!
01784  * \brief Write text frame to a channel
01785  * This function writes the given frame to the indicated channel.
01786  * \param chan destination channel of the frame
01787  * \param frame frame that will be written
01788  * \return It returns 1 on success, 0 if not implemented, and -1 on failure.
01789  */
01790 int ast_write_text(struct ast_channel *chan, struct ast_frame *frame);
01791 
01792 /*! \brief Send empty audio to prime a channel driver */
01793 int ast_prod(struct ast_channel *chan);
01794 
01795 /*!
01796  * \brief Sets read format on channel chan
01797  * Set read format for channel to whichever component of "format" is best.
01798  * \param chan channel to change
01799  * \param format format to change to
01800  * \return Returns 0 on success, -1 on failure
01801  */
01802 int ast_set_read_format(struct ast_channel *chan, format_t format);
01803 
01804 /*!
01805  * \brief Sets write format on channel chan
01806  * Set write format for channel to whichever component of "format" is best.
01807  * \param chan channel to change
01808  * \param format new format for writing
01809  * \return Returns 0 on success, -1 on failure
01810  */
01811 int ast_set_write_format(struct ast_channel *chan, format_t format);
01812 
01813 /*!
01814  * \brief Sends text to a channel
01815  *
01816  * \param chan channel to act upon
01817  * \param text string of text to send on the channel
01818  *
01819  * \details
01820  * Write text to a display on a channel
01821  *
01822  * \note The channel does not need to be locked before calling this function.
01823  *
01824  * \retval 0 on success
01825  * \retval -1 on failure
01826  */
01827 int ast_sendtext(struct ast_channel *chan, const char *text);
01828 
01829 /*!
01830  * \brief Receives a text character from a channel
01831  * \param chan channel to act upon
01832  * \param timeout timeout in milliseconds (0 for infinite wait)
01833  * \details
01834  * Read a char of text from a channel
01835  * \return 0 on success, -1 on failure
01836  */
01837 int ast_recvchar(struct ast_channel *chan, int timeout);
01838 
01839 /*!
01840  * \brief Send a DTMF digit to a channel.
01841  * \param chan channel to act upon
01842  * \param digit the DTMF digit to send, encoded in ASCII
01843  * \param duration the duration of the digit ending in ms
01844  * \return 0 on success, -1 on failure
01845  */
01846 int ast_senddigit(struct ast_channel *chan, char digit, unsigned int duration);
01847 
01848 /*!
01849  * \brief Send a DTMF digit to a channel.
01850  * \param chan channel to act upon
01851  * \param digit the DTMF digit to send, encoded in ASCII
01852  * \return 0 on success, -1 on failure
01853  */
01854 int ast_senddigit_begin(struct ast_channel *chan, char digit);
01855 
01856 /*!
01857  * \brief Send a DTMF digit to a channel.
01858  * \param chan channel to act upon
01859  * \param digit the DTMF digit to send, encoded in ASCII
01860  * \param duration the duration of the digit ending in ms
01861  * \return Returns 0 on success, -1 on failure
01862  */
01863 int ast_senddigit_end(struct ast_channel *chan, char digit, unsigned int duration);
01864 
01865 /*!
01866  * \brief Receives a text string from a channel
01867  * Read a string of text from a channel
01868  * \param chan channel to act upon
01869  * \param timeout timeout in milliseconds (0 for infinite wait)
01870  * \return the received text, or NULL to signify failure.
01871  */
01872 char *ast_recvtext(struct ast_channel *chan, int timeout);
01873 
01874 /*!
01875  * \brief Waits for a digit
01876  * \param c channel to wait for a digit on
01877  * \param ms how many milliseconds to wait
01878  * \return Returns <0 on error, 0 on no entry, and the digit on success.
01879  */
01880 int ast_waitfordigit(struct ast_channel *c, int ms);
01881 
01882 /*!
01883  * \brief Wait for a digit
01884  * Same as ast_waitfordigit() with audio fd for outputting read audio and ctrlfd to monitor for reading.
01885  * \param c channel to wait for a digit on
01886  * \param ms how many milliseconds to wait
01887  * \param audiofd audio file descriptor to write to if audio frames are received
01888  * \param ctrlfd control file descriptor to monitor for reading
01889  * \return Returns 1 if ctrlfd becomes available
01890  */
01891 int ast_waitfordigit_full(struct ast_channel *c, int ms, int audiofd, int ctrlfd);
01892 
01893 /*!
01894  * \brief Reads multiple digits
01895  * \param c channel to read from
01896  * \param s string to read in to.  Must be at least the size of your length
01897  * \param len how many digits to read (maximum)
01898  * \param timeout how long to timeout between digits
01899  * \param rtimeout timeout to wait on the first digit
01900  * \param enders digits to end the string
01901  * \details
01902  * Read in a digit string "s", max length "len", maximum timeout between
01903  * digits "timeout" (-1 for none), terminated by anything in "enders".  Give them rtimeout
01904  * for the first digit.
01905  * \return Returns 0 on normal return, or 1 on a timeout.  In the case of
01906  * a timeout, any digits that were read before the timeout will still be available in s.
01907  * RETURNS 2 in full version when ctrlfd is available, NOT 1
01908  */
01909 int ast_readstring(struct ast_channel *c, char *s, int len, int timeout, int rtimeout, char *enders);
01910 int ast_readstring_full(struct ast_channel *c, char *s, int len, int timeout, int rtimeout, char *enders, int audiofd, int ctrlfd);
01911 
01912 /*! \brief Report DTMF on channel 0 */
01913 #define AST_BRIDGE_DTMF_CHANNEL_0      (1 << 0)
01914 /*! \brief Report DTMF on channel 1 */
01915 #define AST_BRIDGE_DTMF_CHANNEL_1      (1 << 1)
01916 /*! \brief Return all voice frames on channel 0 */
01917 #define AST_BRIDGE_REC_CHANNEL_0    (1 << 2)
01918 /*! \brief Return all voice frames on channel 1 */
01919 #define AST_BRIDGE_REC_CHANNEL_1    (1 << 3)
01920 /*! \brief Ignore all signal frames except NULL */
01921 #define AST_BRIDGE_IGNORE_SIGS         (1 << 4)
01922 
01923 
01924 /*!
01925  * \brief Makes two channel formats compatible
01926  * \param c0 first channel to make compatible
01927  * \param c1 other channel to make compatible
01928  * \details
01929  * Set two channels to compatible formats -- call before ast_channel_bridge in general.
01930  * \return Returns 0 on success and -1 if it could not be done
01931  */
01932 int ast_channel_make_compatible(struct ast_channel *c0, struct ast_channel *c1);
01933 
01934 /*!
01935  * \brief Bridge two channels together (early)
01936  * \param c0 first channel to bridge
01937  * \param c1 second channel to bridge
01938  * \details
01939  * Bridge two channels (c0 and c1) together early. This implies either side may not be answered yet.
01940  * \return Returns 0 on success and -1 if it could not be done
01941  */
01942 int ast_channel_early_bridge(struct ast_channel *c0, struct ast_channel *c1);
01943 
01944 /*!
01945  * \brief Bridge two channels together
01946  * \param c0 first channel to bridge
01947  * \param c1 second channel to bridge
01948  * \param config config for the channels
01949  * \param fo destination frame(?)
01950  * \param rc destination channel(?)
01951  * \details
01952  * Bridge two channels (c0 and c1) together.  If an important frame occurs, we return that frame in
01953  * *rf (remember, it could be NULL) and which channel (0 or 1) in rc
01954  */
01955 /* int ast_channel_bridge(struct ast_channel *c0, struct ast_channel *c1, int flags, struct ast_frame **fo, struct ast_channel **rc); */
01956 int ast_channel_bridge(struct ast_channel *c0,struct ast_channel *c1,
01957    struct ast_bridge_config *config, struct ast_frame **fo, struct ast_channel **rc);
01958 
01959 /*!
01960  * \brief Weird function made for call transfers
01961  *
01962  * \param original channel to make a copy of
01963  * \param clone copy of the original channel
01964  *
01965  * \details
01966  * This is a very strange and freaky function used primarily for transfer.  Suppose that
01967  * "original" and "clone" are two channels in random situations.  This function takes
01968  * the guts out of "clone" and puts them into the "original" channel, then alerts the
01969  * channel driver of the change, asking it to fixup any private information (like the
01970  * p->owner pointer) that is affected by the change.  The physical layer of the original
01971  * channel is hung up.
01972  *
01973  * \note Neither channel passed here should be locked before
01974  * calling this function.  This function performs deadlock
01975  * avoidance involving these two channels.
01976  */
01977 int ast_channel_masquerade(struct ast_channel *original, struct ast_channel *clone);
01978 
01979 /*!
01980  * \brief Setup a masquerade to transfer a call.
01981  * \since 1.8
01982  *
01983  * \param target_chan Target of the call transfer.  (Masquerade original channel)
01984  * \param target_id New connected line information for the target channel.
01985  * \param target_held TRUE if the target call is on hold.
01986  * \param transferee_chan Transferee of the call transfer. (Masquerade clone channel)
01987  * \param transferee_id New connected line information for the transferee channel.
01988  * \param transferee_held TRUE if the transferee call is on hold.
01989  *
01990  * \details
01991  * Party A - Transferee
01992  * Party B - Transferer
01993  * Party C - Target of transfer
01994  *
01995  * Party B transfers A to C.
01996  *
01997  * Party A is connected to bridged channel B1.
01998  * Party B is connected to channels C1 and C2.
01999  * Party C is connected to bridged channel B2.
02000  *
02001  * Party B -- C1 == B1 -- Party A
02002  *               __/
02003  *              /
02004  * Party B -- C2 == B2 -- Party C
02005  *
02006  * Bridged channel B1 is masqueraded into channel C2.  Where B1
02007  * is the masquerade clone channel and C2 is the masquerade
02008  * original channel.
02009  *
02010  * \see ast_channel_masquerade()
02011  *
02012  * \note Has the same locking requirements as ast_channel_masquerade().
02013  *
02014  * \retval 0 on success.
02015  * \retval -1 on error.
02016  */
02017 int ast_channel_transfer_masquerade(
02018    struct ast_channel *target_chan,
02019    const struct ast_party_connected_line *target_id,
02020    int target_held,
02021    struct ast_channel *transferee_chan,
02022    const struct ast_party_connected_line *transferee_id,
02023    int transferee_held);
02024 
02025 /*!
02026  * \brief Gives the string form of a given cause code.
02027  *
02028  * \param state cause to get the description of
02029  * \return the text form of the binary cause code given
02030  */
02031 const char *ast_cause2str(int state) attribute_pure;
02032 
02033 /*!
02034  * \brief Convert the string form of a cause code to a number
02035  *
02036  * \param name string form of the cause
02037  * \return the cause code
02038  */
02039 int ast_str2cause(const char *name) attribute_pure;
02040 
02041 /*!
02042  * \brief Gives the string form of a given channel state
02043  *
02044  * \param ast_channel_state state to get the name of
02045  * \return the text form of the binary state given
02046  */
02047 const char *ast_state2str(enum ast_channel_state);
02048 
02049 /*!
02050  * \brief Gives the string form of a given transfer capability
02051  *
02052  * \param transfercapability transfer capability to get the name of
02053  * \return the text form of the binary transfer capability
02054  */
02055 char *ast_transfercapability2str(int transfercapability) attribute_const;
02056 
02057 /*
02058  * Options: Some low-level drivers may implement "options" allowing fine tuning of the
02059  * low level channel.  See frame.h for options.  Note that many channel drivers may support
02060  * none or a subset of those features, and you should not count on this if you want your
02061  * asterisk application to be portable.  They're mainly useful for tweaking performance
02062  */
02063 
02064 /*!
02065  * \brief Sets an option on a channel
02066  *
02067  * \param channel channel to set options on
02068  * \param option option to change
02069  * \param data data specific to option
02070  * \param datalen length of the data
02071  * \param block blocking or not
02072  * \details
02073  * Set an option on a channel (see frame.h), optionally blocking awaiting the reply
02074  * \return 0 on success and -1 on failure
02075  */
02076 int ast_channel_setoption(struct ast_channel *channel, int option, void *data, int datalen, int block);
02077 
02078 /*! Pick the best codec
02079  * Choose the best codec...  Uhhh...   Yah. */
02080 format_t ast_best_codec(format_t fmts);
02081 
02082 
02083 /*!
02084  * \brief Checks the value of an option
02085  *
02086  * Query the value of an option
02087  * Works similarly to setoption except only reads the options.
02088  */
02089 int ast_channel_queryoption(struct ast_channel *channel, int option, void *data, int *datalen, int block);
02090 
02091 /*!
02092  * \brief Checks for HTML support on a channel
02093  * \return 0 if channel does not support HTML or non-zero if it does
02094  */
02095 int ast_channel_supports_html(struct ast_channel *channel);
02096 
02097 /*!
02098  * \brief Sends HTML on given channel
02099  * Send HTML or URL on link.
02100  * \return 0 on success or -1 on failure
02101  */
02102 int ast_channel_sendhtml(struct ast_channel *channel, int subclass, const char *data, int datalen);
02103 
02104 /*!
02105  * \brief Sends a URL on a given link
02106  * Send URL on link.
02107  * \return 0 on success or -1 on failure
02108  */
02109 int ast_channel_sendurl(struct ast_channel *channel, const char *url);
02110 
02111 /*!
02112  * \brief Defers DTMF so that you only read things like hangups and audio.
02113  * \return non-zero if channel was already DTMF-deferred or
02114  * 0 if channel is just now being DTMF-deferred
02115  */
02116 int ast_channel_defer_dtmf(struct ast_channel *chan);
02117 
02118 /*! Undo defer.  ast_read will return any DTMF characters that were queued */
02119 void ast_channel_undefer_dtmf(struct ast_channel *chan);
02120 
02121 /*! Initiate system shutdown -- prevents new channels from being allocated.
02122  * \param hangup  If "hangup" is non-zero, all existing channels will receive soft
02123  *  hangups */
02124 void ast_begin_shutdown(int hangup);
02125 
02126 /*! Cancels an existing shutdown and returns to normal operation */
02127 void ast_cancel_shutdown(void);
02128 
02129 /*! \return number of channels available for lookup */
02130 int ast_active_channels(void);
02131 
02132 /*! \return the number of channels not yet destroyed */
02133 int ast_undestroyed_channels(void);
02134 
02135 /*! \return non-zero if Asterisk is being shut down */
02136 int ast_shutting_down(void);
02137 
02138 /*! Activate a given generator */
02139 int ast_activate_generator(struct ast_channel *chan, struct ast_generator *gen, void *params);
02140 
02141 /*! Deactivate an active generator */
02142 void ast_deactivate_generator(struct ast_channel *chan);
02143 
02144 /*!
02145  * \brief Set caller ID number, name and ANI and generate AMI event.
02146  *
02147  * \note Use ast_channel_set_caller() and ast_channel_set_caller_event() instead.
02148  * \note The channel does not need to be locked before calling this function.
02149  */
02150 void ast_set_callerid(struct ast_channel *chan, const char *cid_num, const char *cid_name, const char *cid_ani);
02151 
02152 /*!
02153  * \brief Set the caller id information in the Asterisk channel
02154  * \since 1.8
02155  *
02156  * \param chan Asterisk channel to set caller id information
02157  * \param caller Caller id information
02158  * \param update What caller information to update.  NULL if all.
02159  *
02160  * \return Nothing
02161  *
02162  * \note The channel does not need to be locked before calling this function.
02163  */
02164 void ast_channel_set_caller(struct ast_channel *chan, const struct ast_party_caller *caller, const struct ast_set_party_caller *update);
02165 
02166 /*!
02167  * \brief Set the caller id information in the Asterisk channel and generate an AMI event
02168  * if the caller id name or number changed.
02169  * \since 1.8
02170  *
02171  * \param chan Asterisk channel to set caller id information
02172  * \param caller Caller id information
02173  * \param update What caller information to update.  NULL if all.
02174  *
02175  * \return Nothing
02176  *
02177  * \note The channel does not need to be locked before calling this function.
02178  */
02179 void ast_channel_set_caller_event(struct ast_channel *chan, const struct ast_party_caller *caller, const struct ast_set_party_caller *update);
02180 
02181 /*! Set the file descriptor on the channel */
02182 void ast_channel_set_fd(struct ast_channel *chan, int which, int fd);
02183 
02184 /*! Add a channel to an optimized waitfor */
02185 void ast_poll_channel_add(struct ast_channel *chan0, struct ast_channel *chan1);
02186 
02187 /*! Delete a channel from an optimized waitfor */
02188 void ast_poll_channel_del(struct ast_channel *chan0, struct ast_channel *chan1);
02189 
02190 /*! Start a tone going */
02191 int ast_tonepair_start(struct ast_channel *chan, int freq1, int freq2, int duration, int vol);
02192 /*! Stop a tone from playing */
02193 void ast_tonepair_stop(struct ast_channel *chan);
02194 /*! Play a tone pair for a given amount of time */
02195 int ast_tonepair(struct ast_channel *chan, int freq1, int freq2, int duration, int vol);
02196 
02197 /*!
02198  * \brief Automatically service a channel for us...
02199  *
02200  * \retval 0 success
02201  * \retval -1 failure, or the channel is already being autoserviced
02202  */
02203 int ast_autoservice_start(struct ast_channel *chan);
02204 
02205 /*!
02206  * \brief Stop servicing a channel for us...
02207  *
02208  * \note if chan is locked prior to calling ast_autoservice_stop, it
02209  * is likely that there will be a deadlock between the thread that calls
02210  * ast_autoservice_stop and the autoservice thread. It is important
02211  * that chan is not locked prior to this call
02212  *
02213  * \param chan
02214  * \retval 0 success
02215  * \retval -1 error, or the channel has been hungup
02216  */
02217 int ast_autoservice_stop(struct ast_channel *chan);
02218 
02219 /*!
02220  * \brief Ignore certain frame types
02221  * \note Normally, we cache DTMF, IMAGE, HTML, TEXT, and CONTROL frames
02222  * while a channel is in autoservice and queue them up when taken out of
02223  * autoservice.  When this is not desireable, this API may be used to
02224  * cause the channel to ignore those frametypes after the channel is put
02225  * into autoservice, but before autoservice is stopped.
02226  * \retval 0 success
02227  * \retval -1 channel is not in autoservice
02228  */
02229 int ast_autoservice_ignore(struct ast_channel *chan, enum ast_frame_type ftype);
02230 
02231 /*!
02232  * \brief Enable or disable timer ticks for a channel
02233  *
02234  * \param c channel
02235  * \param rate number of timer ticks per second
02236  * \param func callback function
02237  * \param data
02238  *
02239  * \details
02240  * If timers are supported, force a scheduled expiration on the
02241  * timer fd, at which point we call the callback function / data
02242  *
02243  * \note Call this function with a rate of 0 to turn off the timer ticks
02244  *
02245  * \version 1.6.1 changed samples parameter to rate, accomodates new timing methods
02246  */
02247 int ast_settimeout(struct ast_channel *c, unsigned int rate, int (*func)(const void *data), void *data);
02248 
02249 /*!
02250  * \brief Transfer a channel (if supported).
02251  * \retval -1 on error
02252  * \retval 0 if not supported
02253  * \retval 1 if supported and requested
02254  * \param chan current channel
02255  * \param dest destination extension for transfer
02256  */
02257 int ast_transfer(struct ast_channel *chan, char *dest);
02258 
02259 /*!
02260  * \brief Start masquerading a channel
02261  * \note absolutely _NO_ channel locks should be held before calling this function.
02262  * \details
02263  * XXX This is a seriously whacked out operation.  We're essentially putting the guts of
02264  *     the clone channel into the original channel.  Start by killing off the original
02265  *     channel's backend.   I'm not sure we're going to keep this function, because
02266  *     while the features are nice, the cost is very high in terms of pure nastiness. XXX
02267  * \param chan Channel to masquerade
02268  */
02269 int ast_do_masquerade(struct ast_channel *chan);
02270 
02271 /*!
02272  * \brief Find bridged channel
02273  *
02274  * \note This function does _not_ return a reference to the bridged channel.
02275  * The reason for this is mostly historical.  It _should_ return a reference,
02276  * but it will take a lot of work to make the code base account for that.
02277  * So, for now, the old rules still apply for how to handle this function.
02278  * If this function is being used from the channel thread that owns the channel,
02279  * then a reference is already held, and channel locking is not required to
02280  * guarantee that the channel will stay around.  If this function is used
02281  * outside of the associated channel thread, the channel parameter 'chan'
02282  * MUST be locked before calling this function.  Also, 'chan' must remain locked
02283  * for the entire time that the result of this function is being used.
02284  *
02285  * \param chan Current channel
02286  *
02287  * \return A pointer to the bridged channel
02288 */
02289 struct ast_channel *ast_bridged_channel(struct ast_channel *chan);
02290 
02291 /*!
02292  * \brief Inherits channel variable from parent to child channel
02293  * \param parent Parent channel
02294  * \param child Child channel
02295  *
02296  * \details
02297  * Scans all channel variables in the parent channel, looking for those
02298  * that should be copied into the child channel.
02299  * Variables whose names begin with a single '_' are copied into the
02300  * child channel with the prefix removed.
02301  * Variables whose names begin with '__' are copied into the child
02302  * channel with their names unchanged.
02303  */
02304 void ast_channel_inherit_variables(const struct ast_channel *parent, struct ast_channel *child);
02305 
02306 /*!
02307  * \brief adds a list of channel variables to a channel
02308  * \param chan the channel
02309  * \param vars a linked list of variables
02310  *
02311  * \details
02312  * Variable names can be for a regular channel variable or a dialplan function
02313  * that has the ability to be written to.
02314  */
02315 void ast_set_variables(struct ast_channel *chan, struct ast_variable *vars);
02316 
02317 /*!
02318  * \brief An opaque 'object' structure use by silence generators on channels.
02319  */
02320 struct ast_silence_generator;
02321 
02322 /*!
02323  * \brief Starts a silence generator on the given channel.
02324  * \param chan The channel to generate silence on
02325  * \return An ast_silence_generator pointer, or NULL if an error occurs
02326  *
02327  * \details
02328  * This function will cause SLINEAR silence to be generated on the supplied
02329  * channel until it is disabled; if the channel cannot be put into SLINEAR
02330  * mode then the function will fail.
02331  *
02332  * \note
02333  * The pointer returned by this function must be preserved and passed to
02334  * ast_channel_stop_silence_generator when you wish to stop the silence
02335  * generation.
02336  */
02337 struct ast_silence_generator *ast_channel_start_silence_generator(struct ast_channel *chan);
02338 
02339 /*!
02340  * \brief Stops a previously-started silence generator on the given channel.
02341  * \param chan The channel to operate on
02342  * \param state The ast_silence_generator pointer return by a previous call to
02343  * ast_channel_start_silence_generator.
02344  * \return nothing
02345  *
02346  * \details
02347  * This function will stop the operating silence generator and return the channel
02348  * to its previous write format.
02349  */
02350 void ast_channel_stop_silence_generator(struct ast_channel *chan, struct ast_silence_generator *state);
02351 
02352 /*!
02353  * \brief Check if the channel can run in internal timing mode.
02354  * \param chan The channel to check
02355  * \return boolean
02356  *
02357  * \details
02358  * This function will return 1 if internal timing is enabled and the timing
02359  * device is available.
02360  */
02361 int ast_internal_timing_enabled(struct ast_channel *chan);
02362 
02363 /* Misc. functions below */
02364 
02365 /*!
02366  * \brief if fd is a valid descriptor, set *pfd with the descriptor
02367  * \return Return 1 (not -1!) if added, 0 otherwise (so we can add the
02368  * return value to the index into the array)
02369  */
02370 static inline int ast_add_fd(struct pollfd *pfd, int fd)
02371 {
02372    pfd->fd = fd;
02373    pfd->events = POLLIN | POLLPRI;
02374    return fd >= 0;
02375 }
02376 
02377 /*! \brief Helper function for migrating select to poll */
02378 static inline int ast_fdisset(struct pollfd *pfds, int fd, int maximum, int *start)
02379 {
02380    int x;
02381    int dummy = 0;
02382 
02383    if (fd < 0)
02384       return 0;
02385    if (!start)
02386       start = &dummy;
02387    for (x = *start; x < maximum; x++)
02388       if (pfds[x].fd == fd) {
02389          if (x == *start)
02390             (*start)++;
02391          return pfds[x].revents;
02392       }
02393    return 0;
02394 }
02395 
02396 /*! \brief Retrieves the current T38 state of a channel */
02397 static inline enum ast_t38_state ast_channel_get_t38_state(struct ast_channel *chan)
02398 {
02399    enum ast_t38_state state = T38_STATE_UNAVAILABLE;
02400    int datalen = sizeof(state);
02401 
02402    ast_channel_queryoption(chan, AST_OPTION_T38_STATE, &state, &datalen, 0);
02403 
02404    return state;
02405 }
02406 
02407 #define CHECK_BLOCKING(c) do {    \
02408    if (ast_test_flag(c, AST_FLAG_BLOCKING)) {\
02409       if (option_debug) \
02410          ast_log(LOG_DEBUG, "Thread %ld Blocking '%s', already blocked by thread %ld in procedure %s\n", (long) pthread_self(), (c)->name, (long) (c)->blocker, (c)->blockproc); \
02411    } else { \
02412       (c)->blocker = pthread_self(); \
02413       (c)->blockproc = __PRETTY_FUNCTION__; \
02414       ast_set_flag(c, AST_FLAG_BLOCKING); \
02415    } } while (0)
02416 
02417 ast_group_t ast_get_group(const char *s);
02418 
02419 /*! \brief print call- and pickup groups into buffer */
02420 char *ast_print_group(char *buf, int buflen, ast_group_t group);
02421 
02422 /*!
02423  * \brief Convert enum channelreloadreason to text string for manager event
02424  * \param reason The reason for reload (manager, cli, start etc)
02425  */
02426 const char *channelreloadreason2txt(enum channelreloadreason reason);
02427 
02428 /*! \brief return an ast_variable list of channeltypes */
02429 struct ast_variable *ast_channeltype_list(void);
02430 
02431 /*!
02432  * \brief return an english explanation of the code returned thru __ast_request_and_dial's 'outstate' argument
02433  * \param reason  The integer argument, usually taken from AST_CONTROL_ macros
02434  * \return char pointer explaining the code
02435  */
02436 const char *ast_channel_reason2str(int reason);
02437 
02438 /*! \brief channel group info */
02439 struct ast_group_info {
02440    struct ast_channel *chan;
02441    char *category;
02442    char *group;
02443    AST_LIST_ENTRY(ast_group_info) group_list;
02444 };
02445 
02446 #define ast_channel_lock(chan) ao2_lock(chan)
02447 #define ast_channel_unlock(chan) ao2_unlock(chan)
02448 #define ast_channel_trylock(chan) ao2_trylock(chan)
02449 
02450 /*!
02451  * \brief Lock two channels.
02452  */
02453 #define ast_channel_lock_both(chan1, chan2) do { \
02454       ast_channel_lock(chan1); \
02455       while (ast_channel_trylock(chan2)) { \
02456          ast_channel_unlock(chan1); \
02457          sched_yield(); \
02458          ast_channel_lock(chan1); \
02459       } \
02460    } while (0)
02461 
02462 /*!
02463  * \brief Increase channel reference count
02464  *
02465  * \param c the channel
02466  *
02467  * \retval c always
02468  *
02469  * \since 1.8
02470  */
02471 #define ast_channel_ref(c) ({ ao2_ref(c, +1); (c); })
02472 
02473 /*!
02474  * \brief Decrease channel reference count
02475  *
02476  * \param c the channel
02477  *
02478  * \retval NULL always
02479  *
02480  * \since 1.8
02481  */
02482 #define ast_channel_unref(c) ({ ao2_ref(c, -1); (struct ast_channel *) (NULL); })
02483 
02484 /*! Channel Iterating @{ */
02485 
02486 /*!
02487  * \brief A channel iterator
02488  *
02489  * This is an opaque type.
02490  */
02491 struct ast_channel_iterator;
02492 
02493 /*!
02494  * \brief Destroy a channel iterator
02495  *
02496  * \arg i the itereator to destroy
02497  *
02498  * This function is used to destroy a channel iterator that was retrieved by
02499  * using one of the channel_iterator_new() functions.
02500  *
02501  * \return NULL, for convenience to clear out the pointer to the iterator that
02502  * was just destroyed.
02503  *
02504  * \since 1.8
02505  */
02506 struct ast_channel_iterator *ast_channel_iterator_destroy(struct ast_channel_iterator *i);
02507 
02508 /*!
02509  * \brief Create a new channel iterator based on extension
02510  *
02511  * \arg exten The extension that channels must be in
02512  * \arg context The context that channels must be in (optional)
02513  *
02514  * After creating an iterator using this function, the ast_channel_iterator_next()
02515  * function can be used to iterate through all channels that are currently
02516  * in the specified context and extension.
02517  *
02518  * \retval NULL on failure
02519  * \retval a new channel iterator based on the specified parameters
02520  *
02521  * \since 1.8
02522  */
02523 struct ast_channel_iterator *ast_channel_iterator_by_exten_new(const char *exten, const char *context);
02524 
02525 /*!
02526  * \brief Create a new channel iterator based on name
02527  *
02528  * \arg name channel name or channel uniqueid to match
02529  * \arg name_len number of characters in the channel name to match on.  This
02530  *      would be used to match based on name prefix.  If matching on the full
02531  *      channel name is desired, then this parameter should be 0.
02532  *
02533  * After creating an iterator using this function, the ast_channel_iterator_next()
02534  * function can be used to iterate through all channels that exist that have
02535  * the specified name or name prefix.
02536  *
02537  * \retval NULL on failure
02538  * \retval a new channel iterator based on the specified parameters
02539  *
02540  * \since 1.8
02541  */
02542 struct ast_channel_iterator *ast_channel_iterator_by_name_new(const char *name,  size_t name_len);
02543 
02544 /*!
02545  * \brief Create a new channel iterator
02546  *
02547  * After creating an iterator using this function, the ast_channel_iterator_next()
02548  * function can be used to iterate through all channels that exist.
02549  *
02550  * \retval NULL on failure
02551  * \retval a new channel iterator
02552  *
02553  * \since 1.8
02554  */
02555 struct ast_channel_iterator *ast_channel_iterator_all_new(void);
02556 
02557 /*!
02558  * \brief Get the next channel for a channel iterator
02559  *
02560  * \arg i the channel iterator that was created using one of the
02561  *  channel_iterator_new() functions.
02562  *
02563  * This function should be used to iterate through all channels that match a
02564  * specified set of parameters that were provided when the iterator was created.
02565  *
02566  * \retval the next channel that matches the parameters used when the iterator
02567  *         was created.
02568  * \retval NULL, if no more channels match the iterator parameters.
02569  *
02570  * \since 1.8
02571  */
02572 struct ast_channel *ast_channel_iterator_next(struct ast_channel_iterator *i);
02573 
02574 /*! @} End channel iterator definitions. */
02575 
02576 /*!
02577  * \brief Call a function with every active channel
02578  *
02579  * This function executes a callback one time for each active channel on the
02580  * system.  The channel is provided as an argument to the function.
02581  *
02582  * \note Absolutely _NO_ channel locks should be held before calling this function.
02583  * \since 1.8
02584  */
02585 struct ast_channel *ast_channel_callback(ao2_callback_data_fn *cb_fn, void *arg,
02586       void *data, int ao2_flags);
02587 
02588 /*! @{ Channel search functions */
02589 
02590 /*!
02591  * \brief Find a channel by name
02592  *
02593  * \arg name the name or uniqueid of the channel to search for
02594  *
02595  * Find a channel that has the same name as the provided argument.
02596  *
02597  * \retval a channel with the name specified by the argument
02598  * \retval NULL if no channel was found
02599  *
02600  * \since 1.8
02601  */
02602 struct ast_channel *ast_channel_get_by_name(const char *name);
02603 
02604 /*!
02605  * \brief Find a channel by a name prefix
02606  *
02607  * \arg name The channel name or uniqueid prefix to search for
02608  * \arg name_len Only search for up to this many characters from the name
02609  *
02610  * Find a channel that has the same name prefix as specified by the arguments.
02611  *
02612  * \retval a channel with the name prefix specified by the arguments
02613  * \retval NULL if no channel was found
02614  *
02615  * \since 1.8
02616  */
02617 struct ast_channel *ast_channel_get_by_name_prefix(const char *name, size_t name_len);
02618 
02619 /*!
02620  * \brief Find a channel by extension and context
02621  *
02622  * \arg exten the extension to search for
02623  * \arg context the context to search for (optional)
02624  *
02625  * Return a channel that is currently at the specified extension and context.
02626  *
02627  * \retval a channel that is at the specified extension and context
02628  * \retval NULL if no channel was found
02629  *
02630  * \since 1.8
02631  */
02632 struct ast_channel *ast_channel_get_by_exten(const char *exten, const char *context);
02633 
02634 /*! @} End channel search functions. */
02635 
02636 /*!
02637   \brief propagate the linked id between chan and peer
02638  */
02639 void ast_channel_set_linkgroup(struct ast_channel *chan, struct ast_channel *peer);
02640 
02641 
02642 /*!
02643  * \brief Initialize the given name structure.
02644  * \since 1.8
02645  *
02646  * \param init Name structure to initialize.
02647  *
02648  * \return Nothing
02649  */
02650 void ast_party_name_init(struct ast_party_name *init);
02651 
02652 /*!
02653  * \brief Copy the source party name information to the destination party name.
02654  * \since 1.8
02655  *
02656  * \param dest Destination party name
02657  * \param src Source party name
02658  *
02659  * \return Nothing
02660  */
02661 void ast_party_name_copy(struct ast_party_name *dest, const struct ast_party_name *src);
02662 
02663 /*!
02664  * \brief Initialize the given party name structure using the given guide
02665  * for a set update operation.
02666  * \since 1.8
02667  *
02668  * \details
02669  * The initialization is needed to allow a set operation to know if a
02670  * value needs to be updated.  Simple integers need the guide's original
02671  * value in case the set operation is not trying to set a new value.
02672  * String values are simply set to NULL pointers if they are not going
02673  * to be updated.
02674  *
02675  * \param init Party name structure to initialize.
02676  * \param guide Source party name to use as a guide in initializing.
02677  *
02678  * \return Nothing
02679  */
02680 void ast_party_name_set_init(struct ast_party_name *init, const struct ast_party_name *guide);
02681 
02682 /*!
02683  * \brief Set the source party name information into the destination party name.
02684  * \since 1.8
02685  *
02686  * \param dest The name one wishes to update
02687  * \param src The new name values to update the dest
02688  *
02689  * \return Nothing
02690  */
02691 void ast_party_name_set(struct ast_party_name *dest, const struct ast_party_name *src);
02692 
02693 /*!
02694  * \brief Destroy the party name contents
02695  * \since 1.8
02696  *
02697  * \param doomed The party name to destroy.
02698  *
02699  * \return Nothing
02700  */
02701 void ast_party_name_free(struct ast_party_name *doomed);
02702 
02703 /*!
02704  * \brief Initialize the given number structure.
02705  * \since 1.8
02706  *
02707  * \param init Number structure to initialize.
02708  *
02709  * \return Nothing
02710  */
02711 void ast_party_number_init(struct ast_party_number *init);
02712 
02713 /*!
02714  * \brief Copy the source party number information to the destination party number.
02715  * \since 1.8
02716  *
02717  * \param dest Destination party number
02718  * \param src Source party number
02719  *
02720  * \return Nothing
02721  */
02722 void ast_party_number_copy(struct ast_party_number *dest, const struct ast_party_number *src);
02723 
02724 /*!
02725  * \brief Initialize the given party number structure using the given guide
02726  * for a set update operation.
02727  * \since 1.8
02728  *
02729  * \details
02730  * The initialization is needed to allow a set operation to know if a
02731  * value needs to be updated.  Simple integers need the guide's original
02732  * value in case the set operation is not trying to set a new value.
02733  * String values are simply set to NULL pointers if they are not going
02734  * to be updated.
02735  *
02736  * \param init Party number structure to initialize.
02737  * \param guide Source party number to use as a guide in initializing.
02738  *
02739  * \return Nothing
02740  */
02741 void ast_party_number_set_init(struct ast_party_number *init, const struct ast_party_number *guide);
02742 
02743 /*!
02744  * \brief Set the source party number information into the destination party number.
02745  * \since 1.8
02746  *
02747  * \param dest The number one wishes to update
02748  * \param src The new number values to update the dest
02749  *
02750  * \return Nothing
02751  */
02752 void ast_party_number_set(struct ast_party_number *dest, const struct ast_party_number *src);
02753 
02754 /*!
02755  * \brief Destroy the party number contents
02756  * \since 1.8
02757  *
02758  * \param doomed The party number to destroy.
02759  *
02760  * \return Nothing
02761  */
02762 void ast_party_number_free(struct ast_party_number *doomed);
02763 
02764 /*!
02765  * \since 1.8
02766  * \brief Initialize the given subaddress structure.
02767  *
02768  * \param init Subaddress structure to initialize.
02769  *
02770  * \return Nothing
02771  */
02772 void ast_party_subaddress_init(struct ast_party_subaddress *init);
02773 
02774 /*!
02775  * \since 1.8
02776  * \brief Copy the source party subaddress information to the destination party subaddress.
02777  *
02778  * \param dest Destination party subaddress
02779  * \param src Source party subaddress
02780  *
02781  * \return Nothing
02782  */
02783 void ast_party_subaddress_copy(struct ast_party_subaddress *dest, const struct ast_party_subaddress *src);
02784 
02785 /*!
02786  * \since 1.8
02787  * \brief Initialize the given party subaddress structure using the given guide
02788  * for a set update operation.
02789  *
02790  * \details
02791  * The initialization is needed to allow a set operation to know if a
02792  * value needs to be updated.  Simple integers need the guide's original
02793  * value in case the set operation is not trying to set a new value.
02794  * String values are simply set to NULL pointers if they are not going
02795  * to be updated.
02796  *
02797  * \param init Party subaddress structure to initialize.
02798  * \param guide Source party subaddress to use as a guide in initializing.
02799  *
02800  * \return Nothing
02801  */
02802 void ast_party_subaddress_set_init(struct ast_party_subaddress *init, const struct ast_party_subaddress *guide);
02803 
02804 /*!
02805  * \since 1.8
02806  * \brief Set the source party subaddress information into the destination party subaddress.
02807  *
02808  * \param dest The subaddress one wishes to update
02809  * \param src The new subaddress values to update the dest
02810  *
02811  * \return Nothing
02812  */
02813 void ast_party_subaddress_set(struct ast_party_subaddress *dest, const struct ast_party_subaddress *src);
02814 
02815 /*!
02816  * \since 1.8
02817  * \brief Destroy the party subaddress contents
02818  *
02819  * \param doomed The party subaddress to destroy.
02820  *
02821  * \return Nothing
02822  */
02823 void ast_party_subaddress_free(struct ast_party_subaddress *doomed);
02824 
02825 /*!
02826  * \brief Initialize the given party id structure.
02827  * \since 1.8
02828  *
02829  * \param init Party id structure to initialize.
02830  *
02831  * \return Nothing
02832  */
02833 void ast_party_id_init(struct ast_party_id *init);
02834 
02835 /*!
02836  * \brief Copy the source party id information to the destination party id.
02837  * \since 1.8
02838  *
02839  * \param dest Destination party id
02840  * \param src Source party id
02841  *
02842  * \return Nothing
02843  */
02844 void ast_party_id_copy(struct ast_party_id *dest, const struct ast_party_id *src);
02845 
02846 /*!
02847  * \brief Initialize the given party id structure using the given guide
02848  * for a set update operation.
02849  * \since 1.8
02850  *
02851  * \details
02852  * The initialization is needed to allow a set operation to know if a
02853  * value needs to be updated.  Simple integers need the guide's original
02854  * value in case the set operation is not trying to set a new value.
02855  * String values are simply set to NULL pointers if they are not going
02856  * to be updated.
02857  *
02858  * \param init Party id structure to initialize.
02859  * \param guide Source party id to use as a guide in initializing.
02860  *
02861  * \return Nothing
02862  */
02863 void ast_party_id_set_init(struct ast_party_id *init, const struct ast_party_id *guide);
02864 
02865 /*!
02866  * \brief Set the source party id information into the destination party id.
02867  * \since 1.8
02868  *
02869  * \param dest The id one wishes to update
02870  * \param src The new id values to update the dest
02871  * \param update What id information to update.  NULL if all.
02872  *
02873  * \return Nothing
02874  */
02875 void ast_party_id_set(struct ast_party_id *dest, const struct ast_party_id *src, const struct ast_set_party_id *update);
02876 
02877 /*!
02878  * \brief Destroy the party id contents
02879  * \since 1.8
02880  *
02881  * \param doomed The party id to destroy.
02882  *
02883  * \return Nothing
02884  */
02885 void ast_party_id_free(struct ast_party_id *doomed);
02886 
02887 /*!
02888  * \brief Determine the overall presentation value for the given party.
02889  * \since 1.8
02890  *
02891  * \param id Party to determine the overall presentation value.
02892  *
02893  * \return Overall presentation value for the given party.
02894  */
02895 int ast_party_id_presentation(const struct ast_party_id *id);
02896 
02897 /*!
02898  * \brief Initialize the given dialed structure.
02899  * \since 1.8
02900  *
02901  * \param init Dialed structure to initialize.
02902  *
02903  * \return Nothing
02904  */
02905 void ast_party_dialed_init(struct ast_party_dialed *init);
02906 
02907 /*!
02908  * \brief Copy the source dialed party information to the destination dialed party.
02909  * \since 1.8
02910  *
02911  * \param dest Destination dialed party
02912  * \param src Source dialed party
02913  *
02914  * \return Nothing
02915  */
02916 void ast_party_dialed_copy(struct ast_party_dialed *dest, const struct ast_party_dialed *src);
02917 
02918 /*!
02919  * \brief Initialize the given dialed structure using the given
02920  * guide for a set update operation.
02921  * \since 1.8
02922  *
02923  * \details
02924  * The initialization is needed to allow a set operation to know if a
02925  * value needs to be updated.  Simple integers need the guide's original
02926  * value in case the set operation is not trying to set a new value.
02927  * String values are simply set to NULL pointers if they are not going
02928  * to be updated.
02929  *
02930  * \param init Caller structure to initialize.
02931  * \param guide Source dialed to use as a guide in initializing.
02932  *
02933  * \return Nothing
02934  */
02935 void ast_party_dialed_set_init(struct ast_party_dialed *init, const struct ast_party_dialed *guide);
02936 
02937 /*!
02938  * \brief Set the dialed information based on another dialed source
02939  * \since 1.8
02940  *
02941  * This is similar to ast_party_dialed_copy, except that NULL values for
02942  * strings in the src parameter indicate not to update the corresponding dest values.
02943  *
02944  * \param dest The dialed one wishes to update
02945  * \param src The new dialed values to update the dest
02946  *
02947  * \return Nada
02948  */
02949 void ast_party_dialed_set(struct ast_party_dialed *dest, const struct ast_party_dialed *src);
02950 
02951 /*!
02952  * \brief Destroy the dialed party contents
02953  * \since 1.8
02954  *
02955  * \param doomed The dialed party to destroy.
02956  *
02957  * \return Nothing
02958  */
02959 void ast_party_dialed_free(struct ast_party_dialed *doomed);
02960 
02961 /*!
02962  * \since 1.8
02963  * \brief Initialize the given caller structure.
02964  *
02965  * \param init Caller structure to initialize.
02966  *
02967  * \return Nothing
02968  */
02969 void ast_party_caller_init(struct ast_party_caller *init);
02970 
02971 /*!
02972  * \since 1.8
02973  * \brief Copy the source caller information to the destination caller.
02974  *
02975  * \param dest Destination caller
02976  * \param src Source caller
02977  *
02978  * \return Nothing
02979  */
02980 void ast_party_caller_copy(struct ast_party_caller *dest, const struct ast_party_caller *src);
02981 
02982 /*!
02983  * \brief Initialize the given caller structure using the given
02984  * guide for a set update operation.
02985  * \since 1.8
02986  *
02987  * \details
02988  * The initialization is needed to allow a set operation to know if a
02989  * value needs to be updated.  Simple integers need the guide's original
02990  * value in case the set operation is not trying to set a new value.
02991  * String values are simply set to NULL pointers if they are not going
02992  * to be updated.
02993  *
02994  * \param init Caller structure to initialize.
02995  * \param guide Source caller to use as a guide in initializing.
02996  *
02997  * \return Nothing
02998  */
02999 void ast_party_caller_set_init(struct ast_party_caller *init, const struct ast_party_caller *guide);
03000 
03001 /*!
03002  * \brief Set the caller information based on another caller source
03003  * \since 1.8
03004  *
03005  * This is similar to ast_party_caller_copy, except that NULL values for
03006  * strings in the src parameter indicate not to update the corresponding dest values.
03007  *
03008  * \param dest The caller one wishes to update
03009  * \param src The new caller values to update the dest
03010  * \param update What caller information to update.  NULL if all.
03011  *
03012  * \return Nada
03013  */
03014 void ast_party_caller_set(struct ast_party_caller *dest, const struct ast_party_caller *src, const struct ast_set_party_caller *update);
03015 
03016 /*!
03017  * \brief Destroy the caller party contents
03018  * \since 1.8
03019  *
03020  * \param doomed The caller party to destroy.
03021  *
03022  * \return Nothing
03023  */
03024 void ast_party_caller_free(struct ast_party_caller *doomed);
03025 
03026 /*!
03027  * \since 1.8
03028  * \brief Initialize the given connected line structure.
03029  *
03030  * \param init Connected line structure to initialize.
03031  *
03032  * \return Nothing
03033  */
03034 void ast_party_connected_line_init(struct ast_party_connected_line *init);
03035 
03036 /*!
03037  * \since 1.8
03038  * \brief Copy the source connected line information to the destination connected line.
03039  *
03040  * \param dest Destination connected line
03041  * \param src Source connected line
03042  *
03043  * \return Nothing
03044  */
03045 void ast_party_connected_line_copy(struct ast_party_connected_line *dest, const struct ast_party_connected_line *src);
03046 
03047 /*!
03048  * \since 1.8
03049  * \brief Initialize the given connected line structure using the given
03050  * guide for a set update operation.
03051  *
03052  * \details
03053  * The initialization is needed to allow a set operation to know if a
03054  * value needs to be updated.  Simple integers need the guide's original
03055  * value in case the set operation is not trying to set a new value.
03056  * String values are simply set to NULL pointers if they are not going
03057  * to be updated.
03058  *
03059  * \param init Connected line structure to initialize.
03060  * \param guide Source connected line to use as a guide in initializing.
03061  *
03062  * \return Nothing
03063  */
03064 void ast_party_connected_line_set_init(struct ast_party_connected_line *init, const struct ast_party_connected_line *guide);
03065 
03066 /*!
03067  * \since 1.8
03068  * \brief Set the connected line information based on another connected line source
03069  *
03070  * This is similar to ast_party_connected_line_copy, except that NULL values for
03071  * strings in the src parameter indicate not to update the corresponding dest values.
03072  *
03073  * \param dest The connected line one wishes to update
03074  * \param src The new connected line values to update the dest
03075  * \param update What connected line information to update.  NULL if all.
03076  *
03077  * \return Nothing
03078  */
03079 void ast_party_connected_line_set(struct ast_party_connected_line *dest, const struct ast_party_connected_line *src, const struct ast_set_party_connected_line *update);
03080 
03081 /*!
03082  * \since 1.8
03083  * \brief Collect the caller party information into a connected line structure.
03084  *
03085  * \param connected Collected caller information for the connected line
03086  * \param caller Caller information.
03087  *
03088  * \return Nothing
03089  *
03090  * \warning This is a shallow copy.
03091  * \warning DO NOT call ast_party_connected_line_free() on the filled in
03092  * connected line structure!
03093  */
03094 void ast_party_connected_line_collect_caller(struct ast_party_connected_line *connected, struct ast_party_caller *caller);
03095 
03096 /*!
03097  * \since 1.8
03098  * \brief Destroy the connected line information contents
03099  *
03100  * \param doomed The connected line information to destroy.
03101  *
03102  * \return Nothing
03103  */
03104 void ast_party_connected_line_free(struct ast_party_connected_line *doomed);
03105 
03106 /*!
03107  * \brief Initialize the given redirecting structure.
03108  * \since 1.8
03109  *
03110  * \param init Redirecting structure to initialize.
03111  *
03112  * \return Nothing
03113  */
03114 void ast_party_redirecting_init(struct ast_party_redirecting *init);
03115 
03116 /*!
03117  * \since 1.8
03118  * \brief Copy the source redirecting information to the destination redirecting.
03119  *
03120  * \param dest Destination redirecting
03121  * \param src Source redirecting
03122  *
03123  * \return Nothing
03124  */
03125 void ast_party_redirecting_copy(struct ast_party_redirecting *dest, const struct ast_party_redirecting *src);
03126 
03127 /*!
03128  * \since 1.8
03129  * \brief Initialize the given redirecting id structure using the given guide
03130  * for a set update operation.
03131  *
03132  * \details
03133  * The initialization is needed to allow a set operation to know if a
03134  * value needs to be updated.  Simple integers need the guide's original
03135  * value in case the set operation is not trying to set a new value.
03136  * String values are simply set to NULL pointers if they are not going
03137  * to be updated.
03138  *
03139  * \param init Redirecting id structure to initialize.
03140  * \param guide Source redirecting id to use as a guide in initializing.
03141  *
03142  * \return Nothing
03143  */
03144 void ast_party_redirecting_set_init(struct ast_party_redirecting *init, const struct ast_party_redirecting *guide);
03145 
03146 /*!
03147  * \brief Set the redirecting information based on another redirecting source
03148  * \since 1.8
03149  *
03150  * This is similar to ast_party_redirecting_copy, except that NULL values for
03151  * strings in the src parameter indicate not to update the corresponding dest values.
03152  *
03153  * \param dest The redirecting one wishes to update
03154  * \param src The new redirecting values to update the dest
03155  * \param update What redirecting information to update.  NULL if all.
03156  *
03157  * \return Nothing
03158  */
03159 void ast_party_redirecting_set(struct ast_party_redirecting *dest, const struct ast_party_redirecting *src, const struct ast_set_party_redirecting *update);
03160 
03161 /*!
03162  * \since 1.8
03163  * \brief Destroy the redirecting information contents
03164  *
03165  * \param doomed The redirecting information to destroy.
03166  *
03167  * \return Nothing
03168  */
03169 void ast_party_redirecting_free(struct ast_party_redirecting *doomed);
03170 
03171 /*!
03172  * \since 1.8
03173  * \brief Copy the caller information to the connected line information.
03174  *
03175  * \param dest Destination connected line information
03176  * \param src Source caller information
03177  *
03178  * \return Nothing
03179  *
03180  * \note Assumes locks are already acquired
03181  */
03182 void ast_connected_line_copy_from_caller(struct ast_party_connected_line *dest, const struct ast_party_caller *src);
03183 
03184 /*!
03185  * \since 1.8
03186  * \brief Copy the connected line information to the caller information.
03187  *
03188  * \param dest Destination caller information
03189  * \param src Source connected line information
03190  *
03191  * \return Nothing
03192  *
03193  * \note Assumes locks are already acquired
03194  */
03195 void ast_connected_line_copy_to_caller(struct ast_party_caller *dest, const struct ast_party_connected_line *src);
03196 
03197 /*!
03198  * \since 1.8
03199  * \brief Set the connected line information in the Asterisk channel
03200  *
03201  * \param chan Asterisk channel to set connected line information
03202  * \param connected Connected line information
03203  * \param update What connected line information to update.  NULL if all.
03204  *
03205  * \return Nothing
03206  *
03207  * \note The channel does not need to be locked before calling this function.
03208  */
03209 void ast_channel_set_connected_line(struct ast_channel *chan, const struct ast_party_connected_line *connected, const struct ast_set_party_connected_line *update);
03210 
03211 /*!
03212  * \since 1.8
03213  * \brief Build the connected line information data frame.
03214  *
03215  * \param data Buffer to fill with the frame data
03216  * \param datalen Size of the buffer to fill
03217  * \param connected Connected line information
03218  * \param update What connected line information to build.  NULL if all.
03219  *
03220  * \retval -1 if error
03221  * \retval Amount of data buffer used
03222  */
03223 int ast_connected_line_build_data(unsigned char *data, size_t datalen, const struct ast_party_connected_line *connected, const struct ast_set_party_connected_line *update);
03224 
03225 /*!
03226  * \since 1.8
03227  * \brief Parse connected line indication frame data
03228  *
03229  * \param data Buffer with the frame data to parse
03230  * \param datalen Size of the buffer
03231  * \param connected Extracted connected line information
03232  *
03233  * \retval 0 on success.
03234  * \retval -1 on error.
03235  *
03236  * \note The filled in connected line structure needs to be initialized by
03237  * ast_party_connected_line_set_init() before calling.  If defaults are not
03238  * required use ast_party_connected_line_init().
03239  * \note The filled in connected line structure needs to be destroyed by
03240  * ast_party_connected_line_free() when it is no longer needed.
03241  */
03242 int ast_connected_line_parse_data(const unsigned char *data, size_t datalen, struct ast_party_connected_line *connected);
03243 
03244 /*!
03245  * \since 1.8
03246  * \brief Indicate that the connected line information has changed
03247  *
03248  * \param chan Asterisk channel to indicate connected line information
03249  * \param connected Connected line information
03250  * \param update What connected line information to update.  NULL if all.
03251  *
03252  * \return Nothing
03253  */
03254 void ast_channel_update_connected_line(struct ast_channel *chan, const struct ast_party_connected_line *connected, const struct ast_set_party_connected_line *update);
03255 
03256 /*!
03257  * \since 1.8
03258  * \brief Queue a connected line update frame on a channel
03259  *
03260  * \param chan Asterisk channel to indicate connected line information
03261  * \param connected Connected line information
03262  * \param update What connected line information to update.  NULL if all.
03263  *
03264  * \return Nothing
03265  */
03266 void ast_channel_queue_connected_line_update(struct ast_channel *chan, const struct ast_party_connected_line *connected, const struct ast_set_party_connected_line *update);
03267 
03268 /*!
03269  * \since 1.8
03270  * \brief Set the redirecting id information in the Asterisk channel
03271  *
03272  * \param chan Asterisk channel to set redirecting id information
03273  * \param redirecting Redirecting id information
03274  * \param update What redirecting information to update.  NULL if all.
03275  *
03276  * \return Nothing
03277  *
03278  * \note The channel does not need to be locked before calling this function.
03279  */
03280 void ast_channel_set_redirecting(struct ast_channel *chan, const struct ast_party_redirecting *redirecting, const struct ast_set_party_redirecting *update);
03281 
03282 /*!
03283  * \since 1.8
03284  * \brief Build the redirecting id data frame.
03285  *
03286  * \param data Buffer to fill with the frame data
03287  * \param datalen Size of the buffer to fill
03288  * \param redirecting Redirecting id information
03289  * \param update What redirecting information to build.  NULL if all.
03290  *
03291  * \retval -1 if error
03292  * \retval Amount of data buffer used
03293  */
03294 int ast_redirecting_build_data(unsigned char *data, size_t datalen, const struct ast_party_redirecting *redirecting, const struct ast_set_party_redirecting *update);
03295 
03296 /*!
03297  * \since 1.8
03298  * \brief Parse redirecting indication frame data
03299  *
03300  * \param data Buffer with the frame data to parse
03301  * \param datalen Size of the buffer
03302  * \param redirecting Extracted redirecting id information
03303  *
03304  * \retval 0 on success.
03305  * \retval -1 on error.
03306  *
03307  * \note The filled in id structure needs to be initialized by
03308  * ast_party_redirecting_set_init() before calling.
03309  * \note The filled in id structure needs to be destroyed by
03310  * ast_party_redirecting_free() when it is no longer needed.
03311  */
03312 int ast_redirecting_parse_data(const unsigned char *data, size_t datalen, struct ast_party_redirecting *redirecting);
03313 
03314 /*!
03315  * \since 1.8
03316  * \brief Indicate that the redirecting id has changed
03317  *
03318  * \param chan Asterisk channel to indicate redirecting id information
03319  * \param redirecting Redirecting id information
03320  * \param update What redirecting information to update.  NULL if all.
03321  *
03322  * \return Nothing
03323  */
03324 void ast_channel_update_redirecting(struct ast_channel *chan, const struct ast_party_redirecting *redirecting, const struct ast_set_party_redirecting *update);
03325 
03326 /*!
03327  * \since 1.8
03328  * \brief Queue a redirecting update frame on a channel
03329  *
03330  * \param chan Asterisk channel to indicate redirecting id information
03331  * \param redirecting Redirecting id information
03332  * \param update What redirecting information to update.  NULL if all.
03333  *
03334  * \return Nothing
03335  */
03336 void ast_channel_queue_redirecting_update(struct ast_channel *chan, const struct ast_party_redirecting *redirecting, const struct ast_set_party_redirecting *update);
03337 
03338 /*!
03339  * \since 1.8
03340  * \brief Run a connected line interception macro and update a channel's connected line
03341  * information
03342  *
03343  * Whenever we want to update a channel's connected line information, we may need to run
03344  * a macro so that an administrator can manipulate the information before sending it
03345  * out. This function both runs the macro and sends the update to the channel.
03346  *
03347  * \param autoservice_chan Channel to place into autoservice while the macro is running.
03348  *    It is perfectly safe for this to be NULL
03349  * \param macro_chan The channel to run the macro on. Also the channel from which we
03350  *    determine which macro we need to run.
03351  * \param connected_info Either an ast_party_connected_line or ast_frame pointer of type
03352  *    AST_CONTROL_CONNECTED_LINE
03353  * \param caller If true, then run CONNECTED_LINE_CALLER_SEND_MACRO, otherwise run
03354  *    CONNECTED_LINE_CALLEE_SEND_MACRO
03355  * \param frame If true, then connected_info is an ast_frame pointer, otherwise it is an
03356  *    ast_party_connected_line pointer.
03357  * \retval 0 Success
03358  * \retval -1 Either the macro does not exist, or there was an error while attempting to
03359  *    run the macro
03360  *
03361  * \todo Have multiple return codes based on the MACRO_RESULT
03362  * \todo Make constants so that caller and frame can be more expressive than just '1' and
03363  *    '0'
03364  */
03365 int ast_channel_connected_line_macro(struct ast_channel *autoservice_chan, struct ast_channel *macro_chan, const void *connected_info, int caller, int frame);
03366 
03367 /*!
03368  * \brief Insert into an astdata tree, the channel structure.
03369  * \param[in] tree The ast data tree.
03370  * \param[in] chan The channel structure to add to tree.
03371  * \param[in] add_bridged Add the bridged channel to the structure.
03372  * \retval <0 on error.
03373  * \retval 0 on success.
03374  */
03375 int ast_channel_data_add_structure(struct ast_data *tree, struct ast_channel *chan, int add_bridged);
03376 
03377 /*!
03378  * \brief Compare to channel structures using the data api.
03379  * \param[in] tree The search tree generated by the data api.
03380  * \param[in] chan The channel to compare.
03381  * \param[in] structure_name The name of the node of the channel structure.
03382  * \retval 0 The structure matches.
03383  * \retval 1 The structure doesn't matches.
03384  */
03385 int ast_channel_data_cmp_structure(const struct ast_data_search *tree, struct ast_channel *chan,
03386    const char *structure_name);
03387 
03388 /*!
03389  * \since 1.8
03390  * \brief Run a redirecting interception macro and update a channel's redirecting information
03391  *
03392  * \details
03393  * Whenever we want to update a channel's redirecting information, we may need to run
03394  * a macro so that an administrator can manipulate the information before sending it
03395  * out. This function both runs the macro and sends the update to the channel.
03396  *
03397  * \param autoservice_chan Channel to place into autoservice while the macro is running.
03398  * It is perfectly safe for this to be NULL
03399  * \param macro_chan The channel to run the macro on. Also the channel from which we
03400  * determine which macro we need to run.
03401  * \param redirecting_info Either an ast_party_redirecting or ast_frame pointer of type
03402  * AST_CONTROL_REDIRECTING
03403  * \param is_caller If true, then run REDIRECTING_CALLER_SEND_MACRO, otherwise run
03404  * REDIRECTING_CALLEE_SEND_MACRO
03405  * \param is_frame If true, then redirecting_info is an ast_frame pointer, otherwise it is an
03406  * ast_party_redirecting pointer.
03407  *
03408  * \retval 0 Success
03409  * \retval -1 Either the macro does not exist, or there was an error while attempting to
03410  * run the macro
03411  *
03412  * \todo Have multiple return codes based on the MACRO_RESULT
03413  * \todo Make constants so that caller and frame can be more expressive than just '1' and
03414  * '0'
03415  */
03416 int ast_channel_redirecting_macro(struct ast_channel *autoservice_chan, struct ast_channel *macro_chan, const void *redirecting_info, int is_caller, int is_frame);
03417 
03418 #include "asterisk/ccss.h"
03419 
03420 /*!
03421  * \since 1.8
03422  * \brief Set up datastore with CCSS parameters for a channel
03423  *
03424  * \note
03425  * If base_params is NULL, the channel will get the default
03426  * values for all CCSS parameters.
03427  *
03428  * \details
03429  * This function makes use of datastore operations on the channel, so
03430  * it is important to lock the channel before calling this function.
03431  *
03432  * \param chan The channel to create the datastore on
03433  * \param base_params CCSS parameters we wish to copy into the channel
03434  * \retval 0 Success
03435  * \retval -1 Failure
03436  */
03437 int ast_channel_cc_params_init(struct ast_channel *chan,
03438       const struct ast_cc_config_params *base_params);
03439 
03440 /*!
03441  * \since 1.8
03442  * \brief Get the CCSS parameters from a channel
03443  *
03444  * \details
03445  * This function makes use of datastore operations on the channel, so
03446  * it is important to lock the channel before calling this function.
03447  *
03448  * \param chan Channel to retrieve parameters from
03449  * \retval NULL Failure
03450  * \retval non-NULL The parameters desired
03451  */
03452 struct ast_cc_config_params *ast_channel_get_cc_config_params(struct ast_channel *chan);
03453 
03454 
03455 /*!
03456  * \since 1.8
03457  * \brief Get a device name given its channel structure
03458  *
03459  * \details
03460  * A common practice in Asterisk is to determine the device being talked
03461  * to by dissecting the channel name. For certain channel types, this is not
03462  * accurate. For instance, an ISDN channel is named based on what B channel is
03463  * used, not the device being communicated with.
03464  *
03465  * This function interfaces with a channel tech's queryoption callback to
03466  * retrieve the name of the device being communicated with. If the channel does not
03467  * implement this specific option, then the traditional method of using the channel
03468  * name is used instead.
03469  *
03470  * \param chan The channel to retrieve the information from
03471  * \param[out] device_name The buffer to place the device's name into
03472  * \param name_buffer_length The allocated space for the device_name
03473  * \return 0 always
03474  */
03475 int ast_channel_get_device_name(struct ast_channel *chan, char *device_name, size_t name_buffer_length);
03476 
03477 /*!
03478  * \since 1.8
03479  * \brief Find the appropriate CC agent type to use given a channel
03480  *
03481  * \details
03482  * During call completion, we will need to create a call completion agent structure. To
03483  * figure out the type of agent to construct, we need to ask the channel driver for the
03484  * appropriate type.
03485  *
03486  * Prior to adding this function, the call completion core attempted to figure this
03487  * out for itself by stripping the technology off the channel's name. However, in the
03488  * case of chan_dahdi, there are multiple agent types registered, and so simply searching
03489  * for an agent type called "DAHDI" is not possible. In a case where multiple agent types
03490  * are defined, the channel driver must have a queryoption callback defined in its
03491  * channel_tech, and the queryoption callback must handle AST_OPTION_CC_AGENT_TYPE
03492  *
03493  * If a channel driver does not have a queryoption callback or if the queryoption callback
03494  * does not handle AST_OPTION_CC_AGENT_TYPE, then the old behavior of using the technology
03495  * portion of the channel name is used instead. This is perfectly suitable for channel drivers
03496  * whose channel technologies are a one-to-one match with the agent types defined within.
03497  *
03498  * Note that this function is only called when the agent policy on a given channel is set
03499  * to "native." Generic agents' type can be determined automatically by the core.
03500  *
03501  * \param chan The channel for which we wish to retrieve the agent type
03502  * \param[out] agent_type The type of agent the channel driver wants us to use
03503  * \param size The size of the buffer to write to
03504  */
03505 int ast_channel_get_cc_agent_type(struct ast_channel *chan, char *agent_type, size_t size);
03506 #if defined(__cplusplus) || defined(c_plusplus)
03507 }
03508 #endif
03509 
03510 #endif /* _ASTERISK_CHANNEL_H */

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