image.c

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/*
 * Asterisk -- An open source telephony toolkit.
 *
 * Copyright (C) 1999 - 2006, Digium, Inc.
 *
 * Mark Spencer <markster@digium.com>
 *
 * See http://www.asterisk.org for more information about
 * the Asterisk project. Please do not directly contact
 * any of the maintainers of this project for assistance;
 * the project provides a web site, mailing lists and IRC
 * channels for your use.
 *
 * This program is free software, distributed under the terms of
 * the GNU General Public License Version 2. See the LICENSE file
 * at the top of the source tree.
 */

/*! \file
 *
 * \brief Image Management
 *
 * \author Mark Spencer <markster@digium.com>
 */

/*** MODULEINFO
   <support_level>core</support_level>
 ***/

#include "asterisk.h"

ASTERISK_FILE_VERSION(__FILE__, "$Revision: 377883 $")

#include <sys/time.h>
#include <sys/stat.h>
#include <signal.h>

#include "asterisk/paths.h"   /* use ast_config_AST_DATA_DIR */
#include "asterisk/sched.h"
#include "asterisk/channel.h"
#include "asterisk/file.h"
#include "asterisk/image.h"
#include "asterisk/translate.h"
#include "asterisk/cli.h"
#include "asterisk/lock.h"

/* XXX Why don't we just use the formats struct for this? */
static AST_RWLIST_HEAD_STATIC(imagers, ast_imager);

int ast_image_register(struct ast_imager *img)
{
   AST_RWLIST_WRLOCK(&imagers);
   AST_RWLIST_INSERT_HEAD(&imagers, img, list);
   AST_RWLIST_UNLOCK(&imagers);
   ast_verb(2, "Registered format '%s' (%s)\n", img->name, img->desc);
   return 0;
}

void ast_image_unregister(struct ast_imager *img)
{
   AST_RWLIST_WRLOCK(&imagers);
   img = AST_RWLIST_REMOVE(&imagers, img, list);
   AST_RWLIST_UNLOCK(&imagers);

   if (img)
      ast_verb(2, "Unregistered format '%s' (%s)\n", img->name, img->desc);
}

int ast_supports_images(struct ast_channel *chan)
{
   if (!chan || !ast_channel_tech(chan))
      return 0;
   if (!ast_channel_tech(chan)->send_image)
      return 0;
   return 1;
}

static int file_exists(char *filename)
{
   int res;
   struct stat st;
   res = stat(filename, &st);
   if (!res)
      return st.st_size;
   return 0;
}

static void make_filename(char *buf, int len, const char *filename, const char *preflang, char *ext)
{
   if (filename[0] == '/') {
      if (!ast_strlen_zero(preflang))
         snprintf(buf, len, "%s-%s.%s", filename, preflang, ext);
      else
         snprintf(buf, len, "%s.%s", filename, ext);
   } else {
      if (!ast_strlen_zero(preflang))
         snprintf(buf, len, "%s/%s/%s-%s.%s", ast_config_AST_DATA_DIR, "images", filename, preflang, ext);
      else
         snprintf(buf, len, "%s/%s/%s.%s", ast_config_AST_DATA_DIR, "images", filename, ext);
   }
}

struct ast_frame *ast_read_image(const char *filename, const char *preflang, struct ast_format *format)
{
   struct ast_imager *i;
   char buf[256];
   char tmp[80];
   char *e;
   struct ast_imager *found = NULL;
   int fd;
   int len=0;
   struct ast_frame *f = NULL;

   AST_RWLIST_RDLOCK(&imagers);
   AST_RWLIST_TRAVERSE(&imagers, i, list) {
      /* if NULL image format, just pick the first one, otherwise match it. */
      if (!format || (ast_format_cmp(&i->format, format) == AST_FORMAT_CMP_EQUAL)) {
         char *stringp=NULL;
         ast_copy_string(tmp, i->exts, sizeof(tmp));
         stringp = tmp;
         e = strsep(&stringp, "|");
         while (e) {
            make_filename(buf, sizeof(buf), filename, preflang, e);
            if ((len = file_exists(buf))) {
               found = i;
               break;
            }
            make_filename(buf, sizeof(buf), filename, NULL, e);
            if ((len = file_exists(buf))) {
               found = i;
               break;
            }
            e = strsep(&stringp, "|");
         }
      }
      if (found)
         break;
   }

   if (found) {
      fd = open(buf, O_RDONLY);
      if (fd > -1) {
         if (!found->identify || found->identify(fd)) {
            /* Reset file pointer */
            lseek(fd, 0, SEEK_SET);
            f = found->read_image(fd, len);
         } else
            ast_log(LOG_WARNING, "%s does not appear to be a %s file\n", buf, found->name);
         close(fd);
      } else
         ast_log(LOG_WARNING, "Unable to open '%s': %s\n", buf, strerror(errno));
   } else
      ast_log(LOG_WARNING, "Image file '%s' not found\n", filename);

   AST_RWLIST_UNLOCK(&imagers);

   return f;
}

int ast_send_image(struct ast_channel *chan, const char *filename)
{
   struct ast_frame *f;
   int res = -1;
   if (ast_channel_tech(chan)->send_image) {
      f = ast_read_image(filename, ast_channel_language(chan), NULL);
      if (f) {
         res = ast_channel_tech(chan)->send_image(chan, f);
         ast_frfree(f);
      }
   }
   return res;
}

static char *handle_core_show_image_formats(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
{
#define FORMAT "%10s %10s %50s %10s\n"
#define FORMAT2 "%10s %10s %50s %10s\n"
   struct ast_imager *i;
   int count_fmt = 0;

   switch (cmd) {
   case CLI_INIT:
      e->command = "core show image formats";
      e->usage =
         "Usage: core show image formats\n"
         "       Displays currently registered image formats (if any).\n";
      return NULL;
   case CLI_GENERATE:
      return NULL;
   }
   if (a->argc != 4)
      return CLI_SHOWUSAGE;
   ast_cli(a->fd, FORMAT, "Name", "Extensions", "Description", "Format");
   ast_cli(a->fd, FORMAT, "----", "----------", "-----------", "------");
   AST_RWLIST_RDLOCK(&imagers);
   AST_RWLIST_TRAVERSE(&imagers, i, list) {
      ast_cli(a->fd, FORMAT2, i->name, i->exts, i->desc, ast_getformatname(&i->format));
      count_fmt++;
   }
   AST_RWLIST_UNLOCK(&imagers);
   ast_cli(a->fd, "\n%d image format%s registered.\n", count_fmt, count_fmt == 1 ? "" : "s");
   return CLI_SUCCESS;
}

static struct ast_cli_entry cli_image[] = {
   AST_CLI_DEFINE(handle_core_show_image_formats, "Displays image formats")
};

static void image_shutdown(void)
{
   ast_cli_unregister_multiple(cli_image, ARRAY_LEN(cli_image));
}

int ast_image_init(void)
{
   ast_cli_register_multiple(cli_image, ARRAY_LEN(cli_image));
   ast_register_atexit(image_shutdown);
   return 0;
}