Mon Nov 24 15:34:21 2008

Asterisk developer's documentation


translate.c

Go to the documentation of this file.
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  *
00021  * \brief Translate via the use of pseudo channels
00022  *
00023  * \author Mark Spencer <markster@digium.com> 
00024  */
00025 
00026 #include "asterisk.h"
00027 
00028 ASTERISK_FILE_VERSION(__FILE__, "$Revision: 135915 $")
00029 
00030 #include <sys/types.h>
00031 #include <sys/socket.h>
00032 #include <sys/time.h>
00033 #include <unistd.h>
00034 #include <stdlib.h>
00035 #include <string.h>
00036 #include <stdio.h>
00037 
00038 #include "asterisk/lock.h"
00039 #include "asterisk/channel.h"
00040 #include "asterisk/logger.h"
00041 #include "asterisk/translate.h"
00042 #include "asterisk/module.h"
00043 #include "asterisk/options.h"
00044 #include "asterisk/frame.h"
00045 #include "asterisk/sched.h"
00046 #include "asterisk/cli.h"
00047 #include "asterisk/term.h"
00048 
00049 #define MAX_RECALC 200 /* max sample recalc */
00050 
00051 /*! \brief the list of translators */
00052 static AST_LIST_HEAD_STATIC(translators, ast_translator);
00053 
00054 struct translator_path {
00055    struct ast_translator *step;  /*!< Next step translator */
00056    unsigned int cost;      /*!< Complete cost to destination */
00057    unsigned int multistep;    /*!< Multiple conversions required for this translation */
00058 };
00059 
00060 /*! \brief a matrix that, for any pair of supported formats,
00061  * indicates the total cost of translation and the first step.
00062  * The full path can be reconstricted iterating on the matrix
00063  * until step->dstfmt == desired_format.
00064  *
00065  * Array indexes are 'src' and 'dest', in that order.
00066  *
00067  * Note: the lock in the 'translators' list is also used to protect
00068  * this structure.
00069  */
00070 static struct translator_path tr_matrix[MAX_FORMAT][MAX_FORMAT];
00071 
00072 /*! \todo
00073  * TODO: sample frames for each supported input format.
00074  * We build this on the fly, by taking an SLIN frame and using
00075  * the existing converter to play with it.
00076  */
00077 
00078 /*! \brief returns the index of the lowest bit set */
00079 static force_inline int powerof(unsigned int d)
00080 {
00081    int x = ffs(d);
00082 
00083    if (x)
00084       return x - 1;
00085 
00086    ast_log(LOG_WARNING, "No bits set? %d\n", d);
00087 
00088    return -1;
00089 }
00090 
00091 /*
00092  * wrappers around the translator routines.
00093  */
00094 
00095 /*!
00096  * \brief Allocate the descriptor, required outbuf space,
00097  * and possibly also plc and desc.
00098  */
00099 static void *newpvt(struct ast_translator *t)
00100 {
00101    struct ast_trans_pvt *pvt;
00102    int len;
00103    int useplc = t->plc_samples > 0 && t->useplc;   /* cache, because it can change on the fly */
00104    char *ofs;
00105 
00106    /*
00107     * compute the required size adding private descriptor,
00108     * plc, buffer, AST_FRIENDLY_OFFSET.
00109     */
00110    len = sizeof(*pvt) + t->desc_size;
00111    if (useplc)
00112       len += sizeof(plc_state_t);
00113    if (t->buf_size)
00114       len += AST_FRIENDLY_OFFSET + t->buf_size;
00115    pvt = ast_calloc(1, len);
00116    if (!pvt)
00117       return NULL;
00118    pvt->t = t;
00119    ofs = (char *)(pvt + 1);   /* pointer to data space */
00120    if (t->desc_size) {     /* first comes the descriptor */
00121       pvt->pvt = ofs;
00122       ofs += t->desc_size;
00123    }
00124    if (useplc) {        /* then plc state */
00125       pvt->plc = (plc_state_t *)ofs;
00126       ofs += sizeof(plc_state_t);
00127    }
00128    if (t->buf_size)     /* finally buffer and header */
00129       pvt->outbuf = ofs + AST_FRIENDLY_OFFSET;
00130    /* call local init routine, if present */
00131    if (t->newpvt && t->newpvt(pvt)) {
00132       free(pvt);
00133       return NULL;
00134    }
00135    ast_module_ref(t->module);
00136    return pvt;
00137 }
00138 
00139 static void destroy(struct ast_trans_pvt *pvt)
00140 {
00141    struct ast_translator *t = pvt->t;
00142 
00143    if (ast_test_flag(&pvt->f, AST_FRFLAG_FROM_TRANSLATOR)) {
00144       /* If this flag is still set, that means that the translation path has
00145        * been torn down, while we still have a frame out there being used.
00146        * When ast_frfree() gets called on that frame, this ast_trans_pvt
00147        * will get destroyed, too. */
00148 
00149       /* Set the magic hint that this has been requested to be destroyed. */
00150       pvt->datalen = -1;
00151 
00152       return;
00153    }
00154 
00155    if (t->destroy)
00156       t->destroy(pvt);
00157    free(pvt);
00158    ast_module_unref(t->module);
00159 }
00160 
00161 /*! \brief framein wrapper, deals with plc and bound checks.  */
00162 static int framein(struct ast_trans_pvt *pvt, struct ast_frame *f)
00163 {
00164    int16_t *dst = (int16_t *)pvt->outbuf;
00165    int ret;
00166    int samples = pvt->samples;   /* initial value */
00167    
00168    /* Copy the last in jb timing info to the pvt */
00169    ast_copy_flags(&pvt->f, f, AST_FRFLAG_HAS_TIMING_INFO);
00170    pvt->f.ts = f->ts;
00171    pvt->f.len = f->len;
00172    pvt->f.seqno = f->seqno;
00173 
00174    if (f->samples == 0) {
00175       ast_log(LOG_WARNING, "no samples for %s\n", pvt->t->name);
00176    }
00177    if (pvt->t->buffer_samples) { /* do not pass empty frames to callback */
00178       if (f->datalen == 0) { /* perform PLC with nominal framesize of 20ms/160 samples */
00179          if (pvt->plc) {
00180             int l = pvt->t->plc_samples;
00181             if (pvt->samples + l > pvt->t->buffer_samples) {
00182                ast_log(LOG_WARNING, "Out of buffer space\n");
00183                return -1;
00184             }
00185             l = plc_fillin(pvt->plc, dst + pvt->samples, l);
00186             pvt->samples += l;
00187             pvt->datalen = pvt->samples * 2; /* SLIN has 2bytes for 1sample */
00188          }
00189          /* We don't want generic PLC. If the codec has native PLC, then do that */
00190          if (!pvt->t->native_plc)
00191             return 0;
00192       }
00193       if (pvt->samples + f->samples > pvt->t->buffer_samples) {
00194          ast_log(LOG_WARNING, "Out of buffer space\n");
00195          return -1;
00196       }
00197    }
00198    /* we require a framein routine, wouldn't know how to do
00199     * it otherwise.
00200     */
00201    ret = pvt->t->framein(pvt, f);
00202    /* possibly store data for plc */
00203    if (!ret && pvt->plc) {
00204       int l = pvt->t->plc_samples;
00205       if (pvt->samples < l)
00206          l = pvt->samples;
00207       plc_rx(pvt->plc, dst + pvt->samples - l, l);
00208    }
00209    /* diagnostic ... */
00210    if (pvt->samples == samples)
00211       ast_log(LOG_WARNING, "%s did not update samples %d\n",
00212          pvt->t->name, pvt->samples);
00213         return ret;
00214 }
00215 
00216 /*! \brief generic frameout routine.
00217  * If samples and datalen are 0, take whatever is in pvt
00218  * and reset them, otherwise take the values in the caller and
00219  * leave alone the pvt values.
00220  */
00221 struct ast_frame *ast_trans_frameout(struct ast_trans_pvt *pvt,
00222    int datalen, int samples)
00223 {
00224    struct ast_frame *f = &pvt->f;
00225 
00226         if (samples)
00227       f->samples = samples;
00228    else {
00229       if (pvt->samples == 0)
00230          return NULL;
00231       f->samples = pvt->samples;
00232       pvt->samples = 0;
00233    }
00234    if (datalen)
00235       f->datalen = datalen;
00236    else {
00237       f->datalen = pvt->datalen;
00238       pvt->datalen = 0;
00239    }
00240 
00241    f->frametype = AST_FRAME_VOICE;
00242    f->subclass = 1 << (pvt->t->dstfmt);
00243    f->mallocd = 0;
00244    f->offset = AST_FRIENDLY_OFFSET;
00245    f->src = pvt->t->name;
00246    f->data = pvt->outbuf;
00247 
00248    ast_set_flag(f, AST_FRFLAG_FROM_TRANSLATOR);
00249 
00250    return f;
00251 }
00252 
00253 static struct ast_frame *default_frameout(struct ast_trans_pvt *pvt)
00254 {
00255    return ast_trans_frameout(pvt, 0, 0);
00256 }
00257 
00258 /* end of callback wrappers and helpers */
00259 
00260 void ast_translator_free_path(struct ast_trans_pvt *p)
00261 {
00262    struct ast_trans_pvt *pn = p;
00263    while ( (p = pn) ) {
00264       pn = p->next;
00265       destroy(p);
00266    }
00267 }
00268 
00269 /*! \brief Build a chain of translators based upon the given source and dest formats */
00270 struct ast_trans_pvt *ast_translator_build_path(int dest, int source)
00271 {
00272    struct ast_trans_pvt *head = NULL, *tail = NULL;
00273    
00274    source = powerof(source);
00275    dest = powerof(dest);
00276 
00277    if (source == -1 || dest == -1) {
00278       ast_log(LOG_WARNING, "No translator path: (%s codec is not valid)\n", source == -1 ? "starting" : "ending");
00279       return NULL;
00280    }
00281 
00282    AST_LIST_LOCK(&translators);
00283 
00284    while (source != dest) {
00285       struct ast_trans_pvt *cur;
00286       struct ast_translator *t = tr_matrix[source][dest].step;
00287       if (!t) {
00288          ast_log(LOG_WARNING, "No translator path from %s to %s\n", 
00289             ast_getformatname(source), ast_getformatname(dest));
00290          AST_LIST_UNLOCK(&translators);
00291          return NULL;
00292       }
00293       if (!(cur = newpvt(t))) {
00294          ast_log(LOG_WARNING, "Failed to build translator step from %d to %d\n", source, dest);
00295          if (head)
00296             ast_translator_free_path(head);  
00297          AST_LIST_UNLOCK(&translators);
00298          return NULL;
00299       }
00300       if (!head)
00301          head = cur;
00302       else
00303          tail->next = cur;
00304       tail = cur;
00305       cur->nextin = cur->nextout = ast_tv(0, 0);
00306       /* Keep going if this isn't the final destination */
00307       source = cur->t->dstfmt;
00308    }
00309 
00310    AST_LIST_UNLOCK(&translators);
00311    return head;
00312 }
00313 
00314 /*! \brief do the actual translation */
00315 struct ast_frame *ast_translate(struct ast_trans_pvt *path, struct ast_frame *f, int consume)
00316 {
00317    struct ast_trans_pvt *p = path;
00318    struct ast_frame *out = f;
00319    struct timeval delivery;
00320    int has_timing_info;
00321    long ts;
00322    long len;
00323    int seqno;
00324 
00325    has_timing_info = ast_test_flag(f, AST_FRFLAG_HAS_TIMING_INFO);
00326    ts = f->ts;
00327    len = f->len;
00328    seqno = f->seqno;
00329 
00330    /* XXX hmmm... check this below */
00331    if (!ast_tvzero(f->delivery)) {
00332       if (!ast_tvzero(path->nextin)) {
00333          /* Make sure this is in line with what we were expecting */
00334          if (!ast_tveq(path->nextin, f->delivery)) {
00335             /* The time has changed between what we expected and this
00336                most recent time on the new packet.  If we have a
00337                valid prediction adjust our output time appropriately */
00338             if (!ast_tvzero(path->nextout)) {
00339                path->nextout = ast_tvadd(path->nextout,
00340                           ast_tvsub(f->delivery, path->nextin));
00341             }
00342             path->nextin = f->delivery;
00343          }
00344       } else {
00345          /* This is our first pass.  Make sure the timing looks good */
00346          path->nextin = f->delivery;
00347          path->nextout = f->delivery;
00348       }
00349       /* Predict next incoming sample */
00350       path->nextin = ast_tvadd(path->nextin, ast_samp2tv(f->samples, ast_format_rate(f->subclass)));
00351    }
00352    delivery = f->delivery;
00353    for ( ; out && p ; p = p->next) {
00354       framein(p, out);
00355       if (out != f)
00356          ast_frfree(out);
00357       out = p->t->frameout(p);
00358    }
00359    if (consume)
00360       ast_frfree(f);
00361    if (out == NULL)
00362       return NULL;
00363    /* we have a frame, play with times */
00364    if (!ast_tvzero(delivery)) {
00365       /* Regenerate prediction after a discontinuity */
00366       if (ast_tvzero(path->nextout))
00367          path->nextout = ast_tvnow();
00368 
00369       /* Use next predicted outgoing timestamp */
00370       out->delivery = path->nextout;
00371       
00372       /* Predict next outgoing timestamp from samples in this
00373          frame. */
00374       path->nextout = ast_tvadd(path->nextout, ast_samp2tv(out->samples, ast_format_rate(out->subclass)));
00375    } else {
00376       out->delivery = ast_tv(0, 0);
00377       ast_set2_flag(out, has_timing_info, AST_FRFLAG_HAS_TIMING_INFO);
00378       if (has_timing_info) {
00379          out->ts = ts;
00380          out->len = len;
00381          out->seqno = seqno;
00382       }
00383    }
00384    /* Invalidate prediction if we're entering a silence period */
00385    if (out->frametype == AST_FRAME_CNG)
00386       path->nextout = ast_tv(0, 0);
00387    return out;
00388 }
00389 
00390 /*! \brief compute the cost of a single translation step */
00391 static void calc_cost(struct ast_translator *t, int seconds)
00392 {
00393    int num_samples = 0;
00394    struct ast_trans_pvt *pvt;
00395    struct timeval start;
00396    int cost;
00397    int out_rate = ast_format_rate(t->dstfmt);
00398 
00399    if (!seconds)
00400       seconds = 1;
00401    
00402    /* If they don't make samples, give them a terrible score */
00403    if (!t->sample) {
00404       ast_log(LOG_WARNING, "Translator '%s' does not produce sample frames.\n", t->name);
00405       t->cost = 99999;
00406       return;
00407    }
00408 
00409    pvt = newpvt(t);
00410    if (!pvt) {
00411       ast_log(LOG_WARNING, "Translator '%s' appears to be broken and will probably fail.\n", t->name);
00412       t->cost = 99999;
00413       return;
00414    }
00415 
00416    start = ast_tvnow();
00417 
00418    /* Call the encoder until we've processed the required number of samples */
00419    while (num_samples < seconds * out_rate) {
00420       struct ast_frame *f = t->sample();
00421       if (!f) {
00422          ast_log(LOG_WARNING, "Translator '%s' failed to produce a sample frame.\n", t->name);
00423          destroy(pvt);
00424          t->cost = 99999;
00425          return;
00426       }
00427       framein(pvt, f);
00428       ast_frfree(f);
00429       while ((f = t->frameout(pvt))) {
00430          num_samples += f->samples;
00431          ast_frfree(f);
00432       }
00433    }
00434 
00435    cost = ast_tvdiff_ms(ast_tvnow(), start);
00436 
00437    destroy(pvt);
00438 
00439    t->cost = cost / seconds;
00440 
00441    if (!t->cost)
00442       t->cost = 1;
00443 }
00444 
00445 /*!
00446  * \brief rebuild a translation matrix.
00447  * \note This function expects the list of translators to be locked
00448 */
00449 static void rebuild_matrix(int samples)
00450 {
00451    struct ast_translator *t;
00452    int x;      /* source format index */
00453    int y;      /* intermediate format index */
00454    int z;      /* destination format index */
00455 
00456    if (option_debug)
00457       ast_log(LOG_DEBUG, "Resetting translation matrix\n");
00458 
00459    bzero(tr_matrix, sizeof(tr_matrix));
00460 
00461    /* first, compute all direct costs */
00462    AST_LIST_TRAVERSE(&translators, t, list) {
00463       if (!t->active)
00464          continue;
00465 
00466       x = t->srcfmt;
00467       z = t->dstfmt;
00468 
00469       if (samples)
00470          calc_cost(t, samples);
00471      
00472       if (!tr_matrix[x][z].step || t->cost < tr_matrix[x][z].cost) {
00473          tr_matrix[x][z].step = t;
00474          tr_matrix[x][z].cost = t->cost;
00475       }
00476    }
00477 
00478    /*
00479     * For each triple x, y, z of distinct formats, check if there is
00480     * a path from x to z through y which is cheaper than what is
00481     * currently known, and in case, update the matrix.
00482     * Repeat until the matrix is stable.
00483     */
00484    for (;;) {
00485       int changed = 0;
00486       for (x = 0; x < MAX_FORMAT; x++) {      /* source format */
00487          for (y=0; y < MAX_FORMAT; y++) {    /* intermediate format */
00488             if (x == y)                     /* skip ourselves */
00489                continue;
00490 
00491             for (z=0; z<MAX_FORMAT; z++) {  /* dst format */
00492                int newcost;
00493 
00494                if (z == x || z == y)       /* skip null conversions */
00495                   continue;
00496                if (!tr_matrix[x][y].step)  /* no path from x to y */
00497                   continue;
00498                if (!tr_matrix[y][z].step)  /* no path from y to z */
00499                   continue;
00500                newcost = tr_matrix[x][y].cost + tr_matrix[y][z].cost;
00501                if (tr_matrix[x][z].step && newcost >= tr_matrix[x][z].cost)
00502                   continue;               /* x->y->z is more expensive than
00503                                            * the existing path */
00504                /* ok, we can get from x to z via y with a cost that
00505                   is the sum of the transition from x to y and
00506                   from y to z */
00507                    
00508                tr_matrix[x][z].step = tr_matrix[x][y].step;
00509                tr_matrix[x][z].cost = newcost;
00510                tr_matrix[x][z].multistep = 1;
00511                if (option_debug)
00512                   ast_log(LOG_DEBUG, "Discovered %d cost path from %s to %s, via %d\n", tr_matrix[x][z].cost, ast_getformatname(x), ast_getformatname(z), y);
00513                changed++;
00514             }
00515          }
00516       }
00517       if (!changed)
00518          break;
00519    }
00520 }
00521 
00522 /*! \brief CLI "show translation" command handler */
00523 static int show_translation_deprecated(int fd, int argc, char *argv[])
00524 {
00525 #define SHOW_TRANS 13
00526    int x, y, z;
00527    int curlen = 0, longest = 0;
00528 
00529    if (argc > 4) 
00530       return RESULT_SHOWUSAGE;
00531 
00532    AST_LIST_LOCK(&translators);  
00533    
00534    if (argv[2] && !strcasecmp(argv[2], "recalc")) {
00535       z = argv[3] ? atoi(argv[3]) : 1;
00536 
00537       if (z <= 0) {
00538          ast_cli(fd, "         C'mon let's be serious here... defaulting to 1.\n");
00539          z = 1;
00540       }
00541 
00542       if (z > MAX_RECALC) {
00543          ast_cli(fd, "         Maximum limit of recalc exceeded by %d, truncating value to %d\n", z - MAX_RECALC, MAX_RECALC);
00544          z = MAX_RECALC;
00545       }
00546       ast_cli(fd, "         Recalculating Codec Translation (number of sample seconds: %d)\n\n", z);
00547       rebuild_matrix(z);
00548    }
00549 
00550    ast_cli(fd, "         Translation times between formats (in milliseconds) for one second of data\n");
00551    ast_cli(fd, "          Source Format (Rows) Destination Format (Columns)\n\n");
00552    /* Get the length of the longest (usable?) codec name, so we know how wide the left side should be */
00553    for (x = 0; x < SHOW_TRANS; x++) {
00554       curlen = strlen(ast_getformatname(1 << (x)));
00555       if (curlen > longest)
00556          longest = curlen;
00557    }
00558    for (x = -1; x < SHOW_TRANS; x++) {
00559       char line[120];
00560       char *buf = line;
00561       size_t left = sizeof(line) - 1;  /* one initial space */
00562       /* next 2 lines run faster than using ast_build_string() */
00563       *buf++ = ' ';
00564       *buf = '\0';
00565       for (y = -1; y < SHOW_TRANS; y++) {
00566          if (y >= 0)
00567             curlen = strlen(ast_getformatname(1 << (y)));
00568 
00569          if (x >= 0 && y >= 0 && tr_matrix[x][y].step) {
00570             /* XXX 999 is a little hackish
00571                We don't want this number being larger than the shortest (or current) codec
00572                For now, that is "gsm" */
00573             ast_build_string(&buf, &left, "%*d", curlen + 1, tr_matrix[x][y].cost > 999 ? 0 : tr_matrix[x][y].cost);
00574          } else if (x == -1 && y >= 0) {
00575             /* Top row - use a dynamic size */
00576             ast_build_string(&buf, &left, "%*s", curlen + 1, ast_getformatname(1 << (y)) );
00577          } else if (y == -1 && x >= 0) {
00578             /* Left column - use a static size. */
00579             ast_build_string(&buf, &left, "%*s", longest, ast_getformatname(1 << (x)) );
00580          } else if (x >= 0 && y >= 0) {
00581             ast_build_string(&buf, &left, "%*s", curlen + 1, "-");
00582          } else {
00583             ast_build_string(&buf, &left, "%*s", longest, "");
00584          }
00585       }
00586       ast_build_string(&buf, &left, "\n");
00587       ast_cli(fd, line);         
00588    }
00589    AST_LIST_UNLOCK(&translators);
00590    return RESULT_SUCCESS;
00591 }
00592 
00593 static int show_translation(int fd, int argc, char *argv[])
00594 {
00595    int x, y, z;
00596    int curlen = 0, longest = 0;
00597 
00598    if (argc > 5)
00599       return RESULT_SHOWUSAGE;
00600 
00601    AST_LIST_LOCK(&translators);  
00602    
00603    if (argv[3] && !strcasecmp(argv[3], "recalc")) {
00604       z = argv[4] ? atoi(argv[4]) : 1;
00605 
00606       if (z <= 0) {
00607          ast_cli(fd, "         C'mon let's be serious here... defaulting to 1.\n");
00608          z = 1;
00609       }
00610 
00611       if (z > MAX_RECALC) {
00612          ast_cli(fd, "         Maximum limit of recalc exceeded by %d, truncating value to %d\n", z - MAX_RECALC, MAX_RECALC);
00613          z = MAX_RECALC;
00614       }
00615       ast_cli(fd, "         Recalculating Codec Translation (number of sample seconds: %d)\n\n", z);
00616       rebuild_matrix(z);
00617    }
00618 
00619    ast_cli(fd, "         Translation times between formats (in milliseconds) for one second of data\n");
00620    ast_cli(fd, "          Source Format (Rows) Destination Format (Columns)\n\n");
00621    /* Get the length of the longest (usable?) codec name, so we know how wide the left side should be */
00622    for (x = 0; x < SHOW_TRANS; x++) {
00623       curlen = strlen(ast_getformatname(1 << (x)));
00624       if (curlen > longest)
00625          longest = curlen;
00626    }
00627    for (x = -1; x < SHOW_TRANS; x++) {
00628       char line[120];
00629       char *buf = line;
00630       size_t left = sizeof(line) - 1;  /* one initial space */
00631       /* next 2 lines run faster than using ast_build_string() */
00632       *buf++ = ' ';
00633       *buf = '\0';
00634       for (y = -1; y < SHOW_TRANS; y++) {
00635          if (y >= 0)
00636             curlen = strlen(ast_getformatname(1 << (y)));
00637 
00638          if (x >= 0 && y >= 0 && tr_matrix[x][y].step) {
00639             /* XXX 999 is a little hackish
00640                We don't want this number being larger than the shortest (or current) codec
00641                For now, that is "gsm" */
00642             ast_build_string(&buf, &left, "%*d", curlen + 1, tr_matrix[x][y].cost > 999 ? 0 : tr_matrix[x][y].cost);
00643          } else if (x == -1 && y >= 0) {
00644             /* Top row - use a dynamic size */
00645             ast_build_string(&buf, &left, "%*s", curlen + 1, ast_getformatname(1 << (y)) );
00646          } else if (y == -1 && x >= 0) {
00647             /* Left column - use a static size. */
00648             ast_build_string(&buf, &left, "%*s", longest, ast_getformatname(1 << (x)) );
00649          } else if (x >= 0 && y >= 0) {
00650             ast_build_string(&buf, &left, "%*s", curlen + 1, "-");
00651          } else {
00652             ast_build_string(&buf, &left, "%*s", longest, "");
00653          }
00654       }
00655       ast_build_string(&buf, &left, "\n");
00656       ast_cli(fd, line);         
00657    }
00658    AST_LIST_UNLOCK(&translators);
00659    return RESULT_SUCCESS;
00660 }
00661 
00662 static char show_trans_usage[] =
00663 "Usage: core show translation [recalc] [<recalc seconds>]\n"
00664 "       Displays known codec translators and the cost associated\n"
00665 "with each conversion.  If the argument 'recalc' is supplied along\n"
00666 "with optional number of seconds to test a new test will be performed\n"
00667 "as the chart is being displayed.\n";
00668 
00669 static struct ast_cli_entry cli_show_translation_deprecated = {
00670    { "show", "translation", NULL },
00671    show_translation_deprecated, NULL,
00672    NULL };
00673 
00674 static struct ast_cli_entry cli_translate[] = {
00675    { { "core", "show", "translation", NULL },
00676    show_translation, "Display translation matrix",
00677    show_trans_usage, NULL, &cli_show_translation_deprecated },
00678 };
00679 
00680 /*! \brief register codec translator */
00681 int __ast_register_translator(struct ast_translator *t, struct ast_module *mod)
00682 {
00683    static int added_cli = 0;
00684    struct ast_translator *u;
00685 
00686    if (!mod) {
00687       ast_log(LOG_WARNING, "Missing module pointer, you need to supply one\n");
00688       return -1;
00689    }
00690 
00691    if (!t->buf_size) {
00692       ast_log(LOG_WARNING, "empty buf size, you need to supply one\n");
00693       return -1;
00694    }
00695 
00696    t->module = mod;
00697 
00698    t->srcfmt = powerof(t->srcfmt);
00699    t->dstfmt = powerof(t->dstfmt);
00700    t->active = 1;
00701 
00702    if (t->srcfmt == -1 || t->dstfmt == -1) {
00703       ast_log(LOG_WARNING, "Invalid translator path: (%s codec is not valid)\n", t->srcfmt == -1 ? "starting" : "ending");
00704       return -1;
00705    }
00706    if (t->plc_samples) {
00707       if (t->buffer_samples < t->plc_samples) {
00708          ast_log(LOG_WARNING, "plc_samples %d buffer_samples %d\n",
00709             t->plc_samples, t->buffer_samples);
00710          return -1;
00711       }
00712       if (t->dstfmt != powerof(AST_FORMAT_SLINEAR))
00713          ast_log(LOG_WARNING, "plc_samples %d format %x\n",
00714             t->plc_samples, t->dstfmt);
00715    }
00716    if (t->srcfmt >= MAX_FORMAT) {
00717       ast_log(LOG_WARNING, "Source format %s is larger than MAX_FORMAT\n", ast_getformatname(t->srcfmt));
00718       return -1;
00719    }
00720 
00721    if (t->dstfmt >= MAX_FORMAT) {
00722       ast_log(LOG_WARNING, "Destination format %s is larger than MAX_FORMAT\n", ast_getformatname(t->dstfmt));
00723       return -1;
00724    }
00725 
00726    if (t->buf_size) {
00727                /*
00728       * Align buf_size properly, rounding up to the machine-specific
00729       * alignment for pointers.
00730       */
00731       struct _test_align { void *a, *b; } p;
00732       int align = (char *)&p.b - (char *)&p.a;
00733 
00734       t->buf_size = ((t->buf_size + align - 1) / align) * align;
00735    }
00736 
00737    if (t->frameout == NULL)
00738       t->frameout = default_frameout;
00739   
00740    calc_cost(t, 1);
00741 
00742    if (option_verbose > 1) {
00743       char tmp[80];
00744 
00745       ast_verbose(VERBOSE_PREFIX_2 "Registered translator '%s' from format %s to %s, cost %d\n",
00746              term_color(tmp, t->name, COLOR_MAGENTA, COLOR_BLACK, sizeof(tmp)),
00747              ast_getformatname(1 << t->srcfmt), ast_getformatname(1 << t->dstfmt), t->cost);
00748    }
00749 
00750    if (!added_cli) {
00751       ast_cli_register_multiple(cli_translate, sizeof(cli_translate) / sizeof(struct ast_cli_entry));
00752       added_cli++;
00753    }
00754 
00755    AST_LIST_LOCK(&translators);
00756 
00757    /* find any existing translators that provide this same srcfmt/dstfmt,
00758       and put this one in order based on cost */
00759    AST_LIST_TRAVERSE_SAFE_BEGIN(&translators, u, list) {
00760       if ((u->srcfmt == t->srcfmt) &&
00761           (u->dstfmt == t->dstfmt) &&
00762           (u->cost > t->cost)) {
00763          AST_LIST_INSERT_BEFORE_CURRENT(&translators, t, list);
00764          t = NULL;
00765       }
00766    }
00767    AST_LIST_TRAVERSE_SAFE_END;
00768 
00769    /* if no existing translator was found for this format combination,
00770       add it to the beginning of the list */
00771    if (t)
00772       AST_LIST_INSERT_HEAD(&translators, t, list);
00773 
00774    rebuild_matrix(0);
00775 
00776    AST_LIST_UNLOCK(&translators);
00777 
00778    return 0;
00779 }
00780 
00781 /*! \brief unregister codec translator */
00782 int ast_unregister_translator(struct ast_translator *t)
00783 {
00784    char tmp[80];
00785    struct ast_translator *u;
00786    int found = 0;
00787 
00788    AST_LIST_LOCK(&translators);
00789    AST_LIST_TRAVERSE_SAFE_BEGIN(&translators, u, list) {
00790       if (u == t) {
00791          AST_LIST_REMOVE_CURRENT(&translators, list);
00792          if (option_verbose > 1)
00793             ast_verbose(VERBOSE_PREFIX_2 "Unregistered translator '%s' from format %s to %s\n", term_color(tmp, t->name, COLOR_MAGENTA, COLOR_BLACK, sizeof(tmp)), ast_getformatname(1 << t->srcfmt), ast_getformatname(1 << t->dstfmt));
00794          found = 1;
00795          break;
00796       }
00797    }
00798    AST_LIST_TRAVERSE_SAFE_END;
00799 
00800    if (found)
00801       rebuild_matrix(0);
00802 
00803    AST_LIST_UNLOCK(&translators);
00804 
00805    return (u ? 0 : -1);
00806 }
00807 
00808 void ast_translator_activate(struct ast_translator *t)
00809 {
00810    AST_LIST_LOCK(&translators);
00811    t->active = 1;
00812    rebuild_matrix(0);
00813    AST_LIST_UNLOCK(&translators);
00814 }
00815 
00816 void ast_translator_deactivate(struct ast_translator *t)
00817 {
00818    AST_LIST_LOCK(&translators);
00819    t->active = 0;
00820    rebuild_matrix(0);
00821    AST_LIST_UNLOCK(&translators);
00822 }
00823 
00824 /*! \brief Calculate our best translator source format, given costs, and a desired destination */
00825 int ast_translator_best_choice(int *dst, int *srcs)
00826 {
00827    int x,y;
00828    int best = -1;
00829    int bestdst = 0;
00830    int cur, cursrc;
00831    int besttime = INT_MAX;
00832    int beststeps = INT_MAX;
00833    int common = ((*dst) & (*srcs)) & AST_FORMAT_AUDIO_MASK; /* are there common formats ? */
00834 
00835    if (common) { /* yes, pick one and return */
00836       for (cur = 1, y = 0; y <= MAX_AUDIO_FORMAT; cur <<= 1, y++) {
00837          if (cur & common) /* guaranteed to find one */
00838             break;
00839       }
00840       /* We are done, this is a common format to both. */
00841       *srcs = *dst = cur;
00842       return 0;
00843    } else { /* No, we will need to translate */
00844       AST_LIST_LOCK(&translators);
00845       for (cur = 1, y = 0; y <= MAX_AUDIO_FORMAT; cur <<= 1, y++) {
00846          if (! (cur & *dst))
00847             continue;
00848          for (cursrc = 1, x = 0; x <= MAX_AUDIO_FORMAT; cursrc <<= 1, x++) {
00849             if (!(*srcs & cursrc) || !tr_matrix[x][y].step ||
00850                 tr_matrix[x][y].cost >  besttime)
00851                continue;   /* not existing or no better */
00852             if (tr_matrix[x][y].cost < besttime ||
00853                 tr_matrix[x][y].multistep < beststeps) {
00854                /* better than what we have so far */
00855                best = cursrc;
00856                bestdst = cur;
00857                besttime = tr_matrix[x][y].cost;
00858                beststeps = tr_matrix[x][y].multistep;
00859             }
00860          }
00861       }
00862       AST_LIST_UNLOCK(&translators);
00863       if (best > -1) {
00864          *srcs = best;
00865          *dst = bestdst;
00866          best = 0;
00867       }
00868       return best;
00869    }
00870 }
00871 
00872 unsigned int ast_translate_path_steps(unsigned int dest, unsigned int src)
00873 {
00874    unsigned int res = -1;
00875 
00876    /* convert bitwise format numbers into array indices */
00877    src = powerof(src);
00878    dest = powerof(dest);
00879 
00880    if (src == -1 || dest == -1) {
00881       ast_log(LOG_WARNING, "No translator path: (%s codec is not valid)\n", src == -1 ? "starting" : "ending");
00882       return -1;
00883    }
00884    AST_LIST_LOCK(&translators);
00885 
00886    if (tr_matrix[src][dest].step)
00887       res = tr_matrix[src][dest].multistep + 1;
00888 
00889    AST_LIST_UNLOCK(&translators);
00890 
00891    return res;
00892 }
00893 
00894 unsigned int ast_translate_available_formats(unsigned int dest, unsigned int src)
00895 {
00896    unsigned int res = dest;
00897    unsigned int x;
00898    unsigned int src_audio = src & AST_FORMAT_AUDIO_MASK;
00899    unsigned int src_video = src & AST_FORMAT_VIDEO_MASK;
00900 
00901    /* if we don't have a source format, we just have to try all
00902       possible destination formats */
00903    if (!src)
00904       return dest;
00905 
00906    /* If we have a source audio format, get its format index */
00907    if (src_audio)
00908       src_audio = powerof(src_audio);
00909 
00910    /* If we have a source video format, get its format index */
00911    if (src_video)
00912       src_video = powerof(src_video);
00913 
00914    AST_LIST_LOCK(&translators);
00915 
00916    /* For a given source audio format, traverse the list of
00917       known audio formats to determine whether there exists
00918       a translation path from the source format to the
00919       destination format. */
00920    for (x = 1; src_audio && x < AST_FORMAT_MAX_AUDIO; x <<= 1) {
00921       /* if this is not a desired format, nothing to do */
00922       if (!dest & x)
00923          continue;
00924 
00925       /* if the source is supplying this format, then
00926          we can leave it in the result */
00927       if (src & x)
00928          continue;
00929 
00930       /* if we don't have a translation path from the src
00931          to this format, remove it from the result */
00932       if (!tr_matrix[src_audio][powerof(x)].step) {
00933          res &= ~x;
00934          continue;
00935       }
00936 
00937       /* now check the opposite direction */
00938       if (!tr_matrix[powerof(x)][src_audio].step)
00939          res &= ~x;
00940    }
00941 
00942    /* For a given source video format, traverse the list of
00943       known video formats to determine whether there exists
00944       a translation path from the source format to the
00945       destination format. */
00946    for (; src_video && x < AST_FORMAT_MAX_VIDEO; x <<= 1) {
00947       /* if this is not a desired format, nothing to do */
00948       if (!dest & x)
00949          continue;
00950 
00951       /* if the source is supplying this format, then
00952          we can leave it in the result */
00953       if (src & x)
00954          continue;
00955 
00956       /* if we don't have a translation path from the src
00957          to this format, remove it from the result */
00958       if (!tr_matrix[src_video][powerof(x)].step) {
00959          res &= ~x;
00960          continue;
00961       }
00962 
00963       /* now check the opposite direction */
00964       if (!tr_matrix[powerof(x)][src_video].step)
00965          res &= ~x;
00966    }
00967 
00968    AST_LIST_UNLOCK(&translators);
00969 
00970    return res;
00971 }
00972 
00973 void ast_translate_frame_freed(struct ast_frame *fr)
00974 {
00975    struct ast_trans_pvt *pvt;
00976 
00977    ast_clear_flag(fr, AST_FRFLAG_FROM_TRANSLATOR);
00978 
00979    pvt = (struct ast_trans_pvt *) (((char *) fr) - offsetof(struct ast_trans_pvt, f));
00980 
00981    if (pvt->datalen != -1)
00982       return;
00983    
00984    destroy(pvt);
00985 }

Generated on Mon Nov 24 15:34:21 2008 for Asterisk - the Open Source PBX by  doxygen 1.4.7