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format_vox.c

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00001 /*
00002  * Asterisk -- An open source telephony toolkit.
00003  *
00004  * Copyright (C) 1999 - 2005, 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 Flat, binary, ADPCM vox file format.
00022  * \arg File name extensions: vox
00023  * 
00024  * \ingroup formats
00025  */
00026  
00027 #include <unistd.h>
00028 #include <netinet/in.h>
00029 #include <arpa/inet.h>
00030 #include <stdlib.h>
00031 #include <sys/time.h>
00032 #include <stdio.h>
00033 #include <errno.h>
00034 #include <string.h>
00035 
00036 #include "asterisk.h"
00037 
00038 ASTERISK_FILE_VERSION(__FILE__, "$Revision: 7221 $")
00039 
00040 #include "asterisk/lock.h"
00041 #include "asterisk/channel.h"
00042 #include "asterisk/file.h"
00043 #include "asterisk/logger.h"
00044 #include "asterisk/sched.h"
00045 #include "asterisk/module.h"
00046 #include "asterisk/endian.h"
00047 
00048 #define BUF_SIZE 80     /* 160 samples */
00049 
00050 struct ast_filestream {
00051    void *reserved[AST_RESERVED_POINTERS];
00052    /* This is what a filestream means to us */
00053    FILE *f; /* Descriptor */
00054    struct ast_frame fr;          /* Frame information */
00055    char waste[AST_FRIENDLY_OFFSET]; /* Buffer for sending frames, etc */
00056    char empty;                   /* Empty character */
00057    unsigned char buf[BUF_SIZE];  /* Output Buffer */
00058    int lasttimeout;
00059    struct timeval last;
00060    short signal;                 /* Signal level (file side) */
00061    short ssindex;                /* Signal ssindex (file side) */
00062    unsigned char zero_count;           /* counter of consecutive zero samples */
00063    unsigned char next_flag;
00064 };
00065 
00066 
00067 AST_MUTEX_DEFINE_STATIC(vox_lock);
00068 static int glistcnt = 0;
00069 
00070 static char *name = "vox";
00071 static char *desc = "Dialogic VOX (ADPCM) File Format";
00072 static char *exts = "vox";
00073 
00074 static struct ast_filestream *vox_open(FILE *f)
00075 {
00076    /* We don't have any header to read or anything really, but
00077       if we did, it would go here.  We also might want to check
00078       and be sure it's a valid file.  */
00079    struct ast_filestream *tmp;
00080    if ((tmp = malloc(sizeof(struct ast_filestream)))) {
00081       memset(tmp, 0, sizeof(struct ast_filestream));
00082       if (ast_mutex_lock(&vox_lock)) {
00083          ast_log(LOG_WARNING, "Unable to lock vox list\n");
00084          free(tmp);
00085          return NULL;
00086       }
00087       tmp->f = f;
00088       tmp->fr.data = tmp->buf;
00089       tmp->fr.frametype = AST_FRAME_VOICE;
00090       tmp->fr.subclass = AST_FORMAT_ADPCM;
00091       /* datalen will vary for each frame */
00092       tmp->fr.src = name;
00093       tmp->fr.mallocd = 0;
00094       tmp->lasttimeout = -1;
00095       glistcnt++;
00096       ast_mutex_unlock(&vox_lock);
00097       ast_update_use_count();
00098    }
00099    return tmp;
00100 }
00101 
00102 static struct ast_filestream *vox_rewrite(FILE *f, const char *comment)
00103 {
00104    /* We don't have any header to read or anything really, but
00105       if we did, it would go here.  We also might want to check
00106       and be sure it's a valid file.  */
00107    struct ast_filestream *tmp;
00108    if ((tmp = malloc(sizeof(struct ast_filestream)))) {
00109       memset(tmp, 0, sizeof(struct ast_filestream));
00110       if (ast_mutex_lock(&vox_lock)) {
00111          ast_log(LOG_WARNING, "Unable to lock vox list\n");
00112          free(tmp);
00113          return NULL;
00114       }
00115       tmp->f = f;
00116       glistcnt++;
00117       ast_mutex_unlock(&vox_lock);
00118       ast_update_use_count();
00119    } else
00120       ast_log(LOG_WARNING, "Out of memory\n");
00121    return tmp;
00122 }
00123 
00124 static void vox_close(struct ast_filestream *s)
00125 {
00126    if (ast_mutex_lock(&vox_lock)) {
00127       ast_log(LOG_WARNING, "Unable to lock vox list\n");
00128       return;
00129    }
00130    glistcnt--;
00131    ast_mutex_unlock(&vox_lock);
00132    ast_update_use_count();
00133    fclose(s->f);
00134    free(s);
00135    s = NULL;
00136 }
00137 
00138 static struct ast_frame *vox_read(struct ast_filestream *s, int *whennext)
00139 {
00140    int res;
00141    /* Send a frame from the file to the appropriate channel */
00142    s->fr.frametype = AST_FRAME_VOICE;
00143    s->fr.subclass = AST_FORMAT_ADPCM;
00144    s->fr.offset = AST_FRIENDLY_OFFSET;
00145    s->fr.mallocd = 0;
00146    s->fr.data = s->buf;
00147    if ((res = fread(s->buf, 1, BUF_SIZE, s->f)) < 1) {
00148       if (res)
00149          ast_log(LOG_WARNING, "Short read (%d) (%s)!\n", res, strerror(errno));
00150       return NULL;
00151    }
00152    s->fr.samples = res * 2;
00153    s->fr.datalen = res;
00154    *whennext = s->fr.samples;
00155    return &s->fr;
00156 }
00157 
00158 static int vox_write(struct ast_filestream *fs, struct ast_frame *f)
00159 {
00160    int res;
00161    if (f->frametype != AST_FRAME_VOICE) {
00162       ast_log(LOG_WARNING, "Asked to write non-voice frame!\n");
00163       return -1;
00164    }
00165    if (f->subclass != AST_FORMAT_ADPCM) {
00166       ast_log(LOG_WARNING, "Asked to write non-ADPCM frame (%d)!\n", f->subclass);
00167       return -1;
00168    }
00169    if ((res = fwrite(f->data, 1, f->datalen, fs->f)) != f->datalen) {
00170          ast_log(LOG_WARNING, "Bad write (%d/%d): %s\n", res, f->datalen, strerror(errno));
00171          return -1;
00172    }
00173    return 0;
00174 }
00175 
00176 static char *vox_getcomment(struct ast_filestream *s)
00177 {
00178    return NULL;
00179 }
00180 
00181 static int vox_seek(struct ast_filestream *fs, long sample_offset, int whence)
00182 {
00183      off_t offset=0,min,cur,max,distance;
00184    
00185      min = 0;
00186      cur = ftell(fs->f);
00187      fseek(fs->f, 0, SEEK_END);
00188     max = ftell(fs->f);
00189     
00190      /* have to fudge to frame here, so not fully to sample */
00191      distance = sample_offset/2;
00192      if(whence == SEEK_SET)
00193      offset = distance;
00194      else if(whence == SEEK_CUR || whence == SEEK_FORCECUR)
00195      offset = distance + cur;
00196      else if(whence == SEEK_END)
00197      offset = max - distance;
00198      if (whence != SEEK_FORCECUR) {
00199      offset = (offset > max)?max:offset;
00200      offset = (offset < min)?min:offset;
00201      }
00202      fseek(fs->f, offset, SEEK_SET);
00203     return ftell(fs->f);
00204 }
00205 
00206 static int vox_trunc(struct ast_filestream *fs)
00207 {
00208      return ftruncate(fileno(fs->f), ftell(fs->f));
00209 }
00210 
00211 static long vox_tell(struct ast_filestream *fs)
00212 {
00213      off_t offset;
00214      offset = ftell(fs->f) << 1;
00215      return offset; 
00216 }
00217 
00218 int load_module()
00219 {
00220    return ast_format_register(name, exts, AST_FORMAT_ADPCM,
00221                         vox_open,
00222                         vox_rewrite,
00223                         vox_write,
00224                         vox_seek,
00225                         vox_trunc,
00226                         vox_tell,
00227                         vox_read,
00228                         vox_close,
00229                         vox_getcomment);
00230                         
00231                         
00232 }
00233 
00234 int unload_module()
00235 {
00236    return ast_format_unregister(name);
00237 }  
00238 
00239 int usecount()
00240 {
00241    return glistcnt;
00242 }
00243 
00244 char *description()
00245 {
00246    return desc;
00247 }
00248 
00249 
00250 char *key()
00251 {
00252    return ASTERISK_GPL_KEY;
00253 }

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