APEG_STREAM *apeg_open_stream_ex(void *ptr)
{
APEG_LAYER *layer;
Initialize_Decoder();
layer = new_apeg_stream();
if(!layer)
return NULL;
if(setjmp(jmp_buffer))
{
apeg_close_stream((APEG_STREAM*)layer);
return NULL;
}
layer->ext_data.init = _init_func;
layer->ext_data.request = _request_func;
layer->ext_data.skip = _skip_func;
layer->ext_data.ptr = ptr;
layer->pf = pack_fopen_vtable(&ext_vtable, layer);
if(!layer->pf)
apeg_error_jump("Could not open stream");
layer->buffer_type = USER_BUFFER;
setup_stream(layer);
return (APEG_STREAM*)layer;
}
APEG_STREAM *apeg_open_memory_stream(void *mpeg_data, int data_len)
{
APEG_LAYER *layer;
Initialize_Decoder();
layer = new_apeg_stream();
if(!layer)
return NULL;
if(setjmp(jmp_buffer))
{
apeg_close_stream((APEG_STREAM*)layer);
return NULL;
}
layer->mem_data.buf = mpeg_data;
layer->mem_data.bytes_left = data_len;
layer->pf = pack_fopen_vtable(&mem_vtable, layer);
if(!layer->pf)
apeg_error_jump("Could not open stream");
layer->buffer_type = MEMORY_BUFFER;
layer->buffer_size = data_len;
setup_stream(layer);
return (APEG_STREAM*)layer;
}
/* This demonstrates seeking. It opens expackf.c, and reads some characters
* from it.
*/
static void stdio_seek_test(void)
{
FILE *fp;
PACKFILE *f;
char str[8];
fp = fopen("expackf.c", "rb");
if (!fp) {
/* Handle the case where the user is running from a build directory
* directly under the Allegro root directory.
*/
fp = fopen("../../examples/expackf.c", "rb");
}
CHECK(fp, "opening expackf.c");
f = pack_fopen_vtable(&stdio_vtable, fp);
CHECK(f, "reading with stdio");
pack_fseek(f, 33);
pack_fread(str, 7, f);
str[7] = '\0';
textprintf_ex(screen, font, 0, 0, -1, -1, "Reading from \"expackf.c\" with stdio.");
textprintf_ex(screen, font, 0, 20, -1, -1, "Seeking to byte 33, reading 7 bytes:");
textprintf_ex(screen, font, 0, 40, -1, -1, "\"%s\"", str);
textprintf_ex(screen, font, 0, 60, -1, -1, "(Should be \"Allegro\")");
pack_fclose(f);
next();
}
/* This reads the files mysha.pcx and allegro.pcx into a memory block as
* binary data, and then uses the memory vtable to read the bitmaps out of
* the memory block.
*/
static void memread_test(void)
{
PACKFILE *f;
MEMREAD_INFO memread_info;
BITMAP *bmp, *bmp2;
unsigned char *block;
int64_t l1, l2;
PACKFILE *f1, *f2;
l1 = file_size_ex("allegro.pcx");
l2 = file_size_ex("mysha.pcx");
block = malloc(l1 + l2);
/* Read mysha.pcx into the memory block. */
f1 = pack_fopen("allegro.pcx", "rb");
CHECK(f1, "opening allegro.pcx");
pack_fread(block, l1, f1);
pack_fclose(f1);
/* Read allegro.pcx into the memory block. */
f2 = pack_fopen("mysha.pcx", "rb");
CHECK(f2, "opening mysha.pcx");
pack_fread(block + l1, l2, f2);
pack_fclose(f2);
/* Open the memory block as PACKFILE, using our memory vtable. */
memread_info.block = block;
memread_info.length = l1 + l2;
memread_info.offset = 0;
f = pack_fopen_vtable(&memread_vtable, &memread_info);
CHECK(f, "reading from memory block");
/* Read the bitmaps out of the memory block. */
bmp = load_pcx_pf(f, NULL);
CHECK(bmp, "load_pcx_pf");
bmp2 = load_pcx_pf(f, NULL);
CHECK(bmp2, "load_pcx_pf");
blit(bmp, screen, 0, 0, 0, 0, bmp->w, bmp->h);
textprintf_ex(screen, font, bmp->w + 8, 8, -1, -1,
"\"allegro.pcx\"");
textprintf_ex(screen, font, bmp->w + 8, 8 + 20, -1, -1,
"read out of a memory file");
blit(bmp2, screen, 0, 0, 0, bmp->h + 8, bmp2->w, bmp2->h);
textprintf_ex(screen, font, bmp2->w + 8, bmp->h + 8, -1, -1,
"\"mysha.pcx\"");
textprintf_ex(screen, font, bmp2->w + 8, bmp->h + 8 + 20, -1, -1,
"read out of a memory file");
destroy_bitmap(bmp);
destroy_bitmap(bmp2);
pack_fclose(f);
next();
}
/* This reads in allegro.pcx, but it does so by using the stdio vtable. */
static void stdio_read_test(void)
{
FILE *fp, *fp2;
PACKFILE *f;
BITMAP *bmp,*bmp2;
/* Simply open the file with the libc fopen. */
fp = fopen("allegro.pcx", "rb");
CHECK(fp, "opening allegro.pcx");
/* Create a PACKFILE, with our custom stdio vtable. */
f = pack_fopen_vtable(&stdio_vtable, fp);
CHECK(f, "reading with stdio");
/* Now read in the bitmap. */
bmp = load_pcx_pf(f, NULL);
CHECK(bmp, "load_pcx_pf");
/* A little bit hackish, we re-assign the file pointer in our PACKFILE
* to another file.
*/
fp2 = freopen("mysha.pcx", "rb", fp);
CHECK(fp2, "opening mysha.pcx");
/* Read in the other bitmap. */
bmp2 = load_pcx_pf(f, NULL);
CHECK(bmp, "load_pcx_pf");
blit(bmp, screen, 0, 0, 0, 0, bmp->w, bmp->h);
textprintf_ex(screen, font, bmp2->w + 8, 8, -1, -1,
"\"allegro.pcx\"");
textprintf_ex(screen, font, bmp2->w + 8, 8 + 20, -1, -1,
"read with stdio functions");
blit(bmp2, screen, 0, 0, 0, bmp->h + 8, bmp2->w, bmp2->h);
textprintf_ex(screen, font, bmp2->w + 8, bmp->h + 8, -1, -1,
"\"mysha.pcx\"");
textprintf_ex(screen, font, bmp2->w + 8, bmp->h + 8 + 20, -1, -1,
"read with stdio functions");
destroy_bitmap(bmp);
destroy_bitmap(bmp2);
pack_fclose(f);
next();
}
/* This demonstrates writing. It simply saves the two bitmaps into a binary
* file.
*/
static void stdio_write_test(void)
{
FILE *fp;
PACKFILE *f;
BITMAP *bmp, *bmp2;
/* Read the bitmaps. */
bmp = load_pcx("allegro.pcx", NULL);
CHECK(bmp, "load_pcx");
bmp2 = load_pcx("mysha.pcx", NULL);
CHECK(bmp2, "load_pcx");
/* Write them with out custom vtable. */
fp = fopen("expackf.out", "wb");
CHECK(fp, "writing expackf.out");
f = pack_fopen_vtable(&stdio_vtable, fp);
CHECK(f, "writing with stdio");
save_tga_pf(f, bmp, NULL);
save_bmp_pf(f, bmp2, NULL);
destroy_bitmap(bmp);
destroy_bitmap(bmp2);
pack_fclose(f);
/* Now read them in again with our custom vtable. */
fp = fopen("expackf.out", "rb");
CHECK(fp, "fopen");
f = pack_fopen_vtable(&stdio_vtable, fp);
CHECK(f, "reading from stdio");
/* Note: in general you would need to implement a "chunking" system
* that knows where the boundary of each file is. Many file format
* loaders will happily read everything to the end of the file,
* whereas others stop reading as soon as they have all the essential
* data (e.g. there may be some metadata at the end of the file).
* Concatenating bare files together only works in examples programs.
*/
bmp = load_tga_pf(f, NULL);
CHECK(bmp, "load_tga_pf");
bmp2 = load_bmp_pf(f, NULL);
CHECK(bmp2, "load_bmp_pf");
blit(bmp, screen, 0, 0, 0, 0, bmp->w, bmp->h);
textprintf_ex(screen, font, bmp2->w + 8, 8, -1, -1,
"\"allegro.pcx\" (as tga)");
textprintf_ex(screen, font, bmp2->w + 8, 8 + 20, -1, -1,
"wrote with stdio functions");
blit(bmp2, screen, 0, 0, 0, bmp->h + 8, bmp2->w, bmp2->h);
textprintf_ex(screen, font, bmp2->w + 8, bmp->h + 8, -1, -1,
"\"mysha.pcx\" (as bmp)");
textprintf_ex(screen, font, bmp2->w + 8, bmp->h + 8 + 20, -1, -1,
"wrote with stdio functions");
destroy_bitmap(bmp);
destroy_bitmap(bmp2);
pack_fclose(f);
next();
}