00001
00002
00003
00004
00005
00006
00007
00008
00009
00010
00011
00012
00013
00014
00015
00016
00017
00018
00019
00020
00021
00022
00023
00024
00025
00026
00027
00028
00029
00030 #include "asterisk.h"
00031
00032 ASTERISK_FILE_VERSION(__FILE__, "$Revision: 328209 $")
00033
00034 #include "asterisk/mod_format.h"
00035 #include "asterisk/module.h"
00036 #include "asterisk/endian.h"
00037
00038 #include "msgsm.h"
00039
00040
00041
00042
00043
00044 #define GSM_FRAME_SIZE 33
00045 #define GSM_SAMPLES 160
00046
00047
00048
00049 static const char gsm_silence[] =
00050 {0xD8,0x20,0xA2,0xE1,0x5A,0x50,0x00,0x49,0x24,0x92,0x49,0x24,0x50,0x00,0x49
00051 ,0x24,0x92,0x49,0x24,0x50,0x00,0x49,0x24,0x92,0x49,0x24,0x50,0x00,0x49,0x24
00052 ,0x92,0x49,0x24};
00053
00054
00055 static struct ast_frame *gsm_read(struct ast_filestream *s, int *whennext)
00056 {
00057 int res;
00058
00059 s->fr.frametype = AST_FRAME_VOICE;
00060 s->fr.subclass.codec = AST_FORMAT_GSM;
00061 AST_FRAME_SET_BUFFER(&(s->fr), s->buf, AST_FRIENDLY_OFFSET, GSM_FRAME_SIZE)
00062 s->fr.mallocd = 0;
00063 if ((res = fread(s->fr.data.ptr, 1, GSM_FRAME_SIZE, s->f)) != GSM_FRAME_SIZE) {
00064 if (res)
00065 ast_log(LOG_WARNING, "Short read (%d) (%s)!\n", res, strerror(errno));
00066 return NULL;
00067 }
00068 *whennext = s->fr.samples = GSM_SAMPLES;
00069 return &s->fr;
00070 }
00071
00072 static int gsm_write(struct ast_filestream *fs, struct ast_frame *f)
00073 {
00074 int res;
00075 unsigned char gsm[2*GSM_FRAME_SIZE];
00076
00077 if (f->frametype != AST_FRAME_VOICE) {
00078 ast_log(LOG_WARNING, "Asked to write non-voice frame!\n");
00079 return -1;
00080 }
00081 if (f->subclass.codec != AST_FORMAT_GSM) {
00082 ast_log(LOG_WARNING, "Asked to write non-GSM frame (%s)!\n", ast_getformatname(f->subclass.codec));
00083 return -1;
00084 }
00085 if (!(f->datalen % 65)) {
00086
00087 int len=0;
00088 while(len < f->datalen) {
00089 conv65(f->data.ptr + len, gsm);
00090 if ((res = fwrite(gsm, 1, 2*GSM_FRAME_SIZE, fs->f)) != 2*GSM_FRAME_SIZE) {
00091 ast_log(LOG_WARNING, "Bad write (%d/66): %s\n", res, strerror(errno));
00092 return -1;
00093 }
00094 len += 65;
00095 }
00096 } else {
00097 if (f->datalen % GSM_FRAME_SIZE) {
00098 ast_log(LOG_WARNING, "Invalid data length, %d, should be multiple of 33\n", f->datalen);
00099 return -1;
00100 }
00101 if ((res = fwrite(f->data.ptr, 1, f->datalen, fs->f)) != f->datalen) {
00102 ast_log(LOG_WARNING, "Bad write (%d/33): %s\n", res, strerror(errno));
00103 return -1;
00104 }
00105 }
00106 return 0;
00107 }
00108
00109 static int gsm_seek(struct ast_filestream *fs, off_t sample_offset, int whence)
00110 {
00111 off_t offset=0,min,cur,max,distance;
00112
00113 min = 0;
00114 cur = ftello(fs->f);
00115 fseeko(fs->f, 0, SEEK_END);
00116 max = ftello(fs->f);
00117
00118 distance = (sample_offset/GSM_SAMPLES) * GSM_FRAME_SIZE;
00119 if(whence == SEEK_SET)
00120 offset = distance;
00121 else if(whence == SEEK_CUR || whence == SEEK_FORCECUR)
00122 offset = distance + cur;
00123 else if(whence == SEEK_END)
00124 offset = max - distance;
00125
00126 offset = (offset < min)?min:offset;
00127 if (whence != SEEK_FORCECUR) {
00128 offset = (offset > max)?max:offset;
00129 } else if (offset > max) {
00130 int i;
00131 fseeko(fs->f, 0, SEEK_END);
00132 for (i=0; i< (offset - max) / GSM_FRAME_SIZE; i++) {
00133 if (!fwrite(gsm_silence, 1, GSM_FRAME_SIZE, fs->f)) {
00134 ast_log(LOG_WARNING, "fwrite() failed: %s\n", strerror(errno));
00135 }
00136 }
00137 }
00138 return fseeko(fs->f, offset, SEEK_SET);
00139 }
00140
00141 static int gsm_trunc(struct ast_filestream *fs)
00142 {
00143 return ftruncate(fileno(fs->f), ftello(fs->f));
00144 }
00145
00146 static off_t gsm_tell(struct ast_filestream *fs)
00147 {
00148 off_t offset = ftello(fs->f);
00149 return (offset/GSM_FRAME_SIZE)*GSM_SAMPLES;
00150 }
00151
00152 static const struct ast_format gsm_f = {
00153 .name = "gsm",
00154 .exts = "gsm",
00155 .format = AST_FORMAT_GSM,
00156 .write = gsm_write,
00157 .seek = gsm_seek,
00158 .trunc = gsm_trunc,
00159 .tell = gsm_tell,
00160 .read = gsm_read,
00161 .buf_size = 2*GSM_FRAME_SIZE + AST_FRIENDLY_OFFSET,
00162 };
00163
00164 static int load_module(void)
00165 {
00166 if (ast_format_register(&gsm_f))
00167 return AST_MODULE_LOAD_FAILURE;
00168 return AST_MODULE_LOAD_SUCCESS;
00169 }
00170
00171 static int unload_module(void)
00172 {
00173 return ast_format_unregister(gsm_f.name);
00174 }
00175
00176 AST_MODULE_INFO(ASTERISK_GPL_KEY, AST_MODFLAG_LOAD_ORDER, "Raw GSM data",
00177 .load = load_module,
00178 .unload = unload_module,
00179 .load_pri = AST_MODPRI_APP_DEPEND
00180 );