apps/plugins/imageviewer/image_decoder.c

   1 /***************************************************************************
   2  *             __________               __   ___.
   3  *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
   4  *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
   5  *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
   6  *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
   7  *                     \/            \/     \/    \/            \/
   8  * $Id$
   9  *
  10  * load image decoder.
  11  *
  12  * This program is free software; you can redistribute it and/or
  13  * modify it under the terms of the GNU General Public License
  14  * as published by the Free Software Foundation; either version 2
  15  * of the License, or (at your option) any later version.
  16  *
  17  * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
  18  * KIND, either express or implied.
  19  *
  20  ****************************************************************************/
  21
  22 #include "plugin.h"
  23 #include "imageviewer.h"
  24 #include "image_decoder.h"
  25
  26 static const char *decoder_names[MAX_IMAGE_TYPES] = {
  27     "bmp",
  28     "jpeg",
  29     "png",
  30 };
  31
  32 /* check file type by extention */
  33 enum image_type get_image_type(const char *name)
  34 {
  35     static const struct {
  36         char *ext;
  37         enum image_type type;
  38     } ext_list[] = {
  39         { ".bmp",   IMAGE_BMP  },
  40         { ".jpg",   IMAGE_JPEG },
  41         { ".jpe",   IMAGE_JPEG },
  42         { ".jpeg",  IMAGE_JPEG },
  43         { ".png",   IMAGE_PNG  },
  44     };
  45
  46     const char *ext = rb->strrchr(name, '.');
  47     int i;
  48     if (!ext)
  49         return IMAGE_UNKNOWN;
  50
  51     for (i = 0; i < (int)ARRAYLEN(ext_list); i++)
  52     {
  53         if (!rb->strcasecmp(ext, ext_list[i].ext))
  54             return ext_list[i].type;
  55     }
  56     return IMAGE_UNKNOWN;
  57 }
  58
  59 static void *decoder_handle = NULL;
  60 const struct image_decoder *load_decoder(struct loader_info *loader_info)
  61 {
  62     const char *name;
  63     char filename[MAX_PATH];
  64     struct imgdec_header *hdr;
  65     struct lc_header     *lc_hdr;
  66
  67     if (loader_info->type < 0 || loader_info->type >= MAX_IMAGE_TYPES)
  68     {
  69         rb->splashf(2*HZ, "Unknown type: %d", loader_info->type);
  70         goto error;
  71     }
  72
  73     release_decoder();
  74
  75     name = decoder_names[loader_info->type];
  76     rb->snprintf(filename, MAX_PATH, VIEWERS_DIR "/%s.ovl", name);
  77
  78     /* load decoder to the buffer. */
  79     decoder_handle = rb->lc_open(filename, loader_info->buffer, loader_info->size);
  80     if (!decoder_handle)
  81     {
  82         rb->splashf(2*HZ, "Can't open %s", filename);
  83         goto error;
  84     }
  85
  86     hdr = rb->lc_get_header(decoder_handle);
  87     if (!hdr)
  88     {
  89         rb->splash(2*HZ, "Can't get header");
  90         goto error_close;
  91     }
  92     lc_hdr = &hdr->lc_hdr;
  93
  94     if (lc_hdr->magic != PLUGIN_MAGIC || lc_hdr->target_id != TARGET_ID)
  95     {
  96         rb->splashf(2*HZ, "%s decoder: Incompatible model.", name);
  97         goto error_close;
  98     }
  99
 100     if (lc_hdr->api_version != IMGDEC_API_VERSION)
 101     {
 102         rb->splashf(2*HZ, "%s decoder: Incompatible version.", name);
 103         goto error_close;
 104     }
 105
 106     *(hdr->api) = rb;
 107     *(hdr->img_api) = loader_info->iv;
 108
 109     /* set remaining buffer size to loader_info. decoder will
 110      * be loaded to the end of the buffer, so fix size only. */
 111 #if (CONFIG_PLATFORM & PLATFORM_NATIVE)
 112     loader_info->size = lc_hdr->load_addr - loader_info->buffer;
 113 #endif
 114
 115     return hdr->decoder;
 116
 117 error_close:
 118     release_decoder();
 119 error:
 120     return NULL;
 121 }
 122
 123 void release_decoder(void)
 124 {
 125     if (decoder_handle != NULL)
 126     {
 127         rb->lc_close(decoder_handle);
 128         decoder_handle = NULL;
 129     }
 130 }