int
get_gif_saved_images( GifFileType *gif, int subimage, SavedImage **ret, int *ret_images )
{
GifRecordType RecordType;
GifByteType *ExtData;
SavedImage temp_save;
int curr_image = 0, ret_count = *ret_images ;
int status = GIF_OK;
memset( &temp_save, 0x00, sizeof( temp_save ) );
do
{
if ( (status = DGifGetRecordType(gif, &RecordType)) == GIF_ERROR)
{
break;
}
switch (RecordType)
{
case IMAGE_DESC_RECORD_TYPE:
if ((status = get_gif_image_desc(gif, &temp_save)) == GIF_OK)
{
int size = temp_save.ImageDesc.Width*temp_save.ImageDesc.Height ;
temp_save.RasterBits = realloc( temp_save.RasterBits, size );
status = DGifGetLine(gif, (unsigned char*)temp_save.RasterBits, size);
if (status == GIF_OK)
{
if( curr_image == subimage || subimage < 0 )
{
append_gif_saved_image( &temp_save, ret, &(ret_count));
}
}
++curr_image ;
}
break;
case EXTENSION_RECORD_TYPE:
status = DGifGetExtension(gif,&temp_save.Function,&ExtData);
while (ExtData != NULL && status == GIF_OK )
{
/* Create an extension block with our data */
if ((status = AddExtensionBlock(&temp_save, ExtData[0], (char*)&(ExtData[1]))) == GIF_OK)
status = DGifGetExtensionNext(gif, &ExtData);
temp_save.Function = 0;
}
break;
case TERMINATE_RECORD_TYPE:
break;
default: /* Should be trapped by DGifGetRecordType */
break;
}
}while( status == GIF_OK && RecordType != TERMINATE_RECORD_TYPE);
/* if( status == GIF_OK && *ret == NULL )
append_gif_saved_image( &temp_save, ret, &(ret_count));
else
*/
free_gif_saved_image( &temp_save, True );
*ret_images = ret_count ;
return status;
}
/******************************************************************************
* This routine reads an entire GIF into core, hanging all its state info off *
* the GifFileType pointer. Call DGifOpenFileName() or DGifOpenFileHandle() *
* first to initialize I/O. Its inverse is EGifSpew(). *
*
******************************************************************************/
int DGifSlurp(GifFileType *GifFile)
{
int i, j, Error, ImageSize;
GifRecordType RecordType;
SavedImage *sp;
GifByteType *ExtData;
SavedImage temp_save;
temp_save.ExtensionBlocks=NULL;
temp_save.ExtensionBlockCount=0;
do {
if (DGifGetRecordType(GifFile, &RecordType) == GIF_ERROR)
return(GIF_ERROR);
switch (RecordType) {
case IMAGE_DESC_RECORD_TYPE:
if (DGifGetImageDesc(GifFile) == GIF_ERROR)
return(GIF_ERROR);
sp = &GifFile->SavedImages[GifFile->ImageCount-1];
ImageSize = sp->ImageDesc.Width * sp->ImageDesc.Height;
sp->RasterBits
= (char *) malloc(ImageSize * sizeof(GifPixelType));
if (DGifGetLine(GifFile, (GifByteType*)sp->RasterBits, ImageSize)
== GIF_ERROR)
return(GIF_ERROR);
if (temp_save.ExtensionBlocks) {
sp->ExtensionBlocks = temp_save.ExtensionBlocks;
sp->ExtensionBlockCount = temp_save.ExtensionBlockCount;
temp_save.ExtensionBlocks = NULL;
temp_save.ExtensionBlockCount=0;
/* FIXME: The following is wrong. It is left in only for backwards
* compatibility. Someday it should go away. Use the
* sp->ExtensionBlocks->Function variable instead.
*/
sp->Function = sp->ExtensionBlocks[0].Function;
}
break;
case EXTENSION_RECORD_TYPE:
if (DGifGetExtension(GifFile,&temp_save.Function,&ExtData)==GIF_ERROR)
return(GIF_ERROR);
while (ExtData != NULL) {
/* Create an extension block with our data */
if (AddExtensionBlock(&temp_save, ExtData[0], (char*)&ExtData[1])
== GIF_ERROR)
return (GIF_ERROR);
if (DGifGetExtensionNext(GifFile, &ExtData) == GIF_ERROR)
return(GIF_ERROR);
temp_save.Function = 0;
}
break;
case TERMINATE_RECORD_TYPE:
break;
default: /* Should be trapped by DGifGetRecordType */
break;
}
} while (RecordType != TERMINATE_RECORD_TYPE);
/* Just in case the Gif has an extension block without an associated
* image... (Should we save this into a savefile structure with no image
* instead? Have to check if the present writing code can handle that as
* well....
*/
if (temp_save.ExtensionBlocks)
FreeExtension(&temp_save);
return(GIF_OK);
}
SkCodec::Result SkGifCodec::ReadUpToFirstImage(GifFileType* gif, uint32_t* transIndex) {
// Use this as a container to hold information about any gif extension
// blocks. This generally stores transparency and animation instructions.
SavedImage saveExt;
SkAutoTCallVProc<SavedImage, FreeExtension> autoFreeExt(&saveExt);
saveExt.ExtensionBlocks = nullptr;
saveExt.ExtensionBlockCount = 0;
GifByteType* extData;
int32_t extFunction;
// We will loop over components of gif images until we find an image. Once
// we find an image, we will decode and return it. While many gif files
// contain more than one image, we will simply decode the first image.
GifRecordType recordType;
do {
// Get the current record type
if (GIF_ERROR == DGifGetRecordType(gif, &recordType)) {
return gif_error("DGifGetRecordType failed.\n", kInvalidInput);
}
switch (recordType) {
case IMAGE_DESC_RECORD_TYPE: {
*transIndex = find_trans_index(saveExt);
// FIXME: Gif files may have multiple images stored in a single
// file. This is most commonly used to enable
// animations. Since we are leaving animated gifs as a
// TODO, we will return kSuccess after decoding the
// first image in the file. This is the same behavior
// as SkImageDecoder_libgif.
//
// Most times this works pretty well, but sometimes it
// doesn't. For example, I have an animated test image
// where the first image in the file is 1x1, but the
// subsequent images are meaningful. This currently
// displays the 1x1 image, which is not ideal. Right
// now I am leaving this as an issue that will be
// addressed when we implement animated gifs.
//
// It is also possible (not explicitly disallowed in the
// specification) that gif files provide multiple
// images in a single file that are all meant to be
// displayed in the same frame together. I will
// currently leave this unimplemented until I find a
// test case that expects this behavior.
return kSuccess;
}
// Extensions are used to specify special properties of the image
// such as transparency or animation.
case EXTENSION_RECORD_TYPE:
// Read extension data
if (GIF_ERROR == DGifGetExtension(gif, &extFunction, &extData)) {
return gif_error("Could not get extension.\n", kIncompleteInput);
}
// Create an extension block with our data
while (nullptr != extData) {
// Add a single block
#if GIFLIB_MAJOR < 5
if (AddExtensionBlock(&saveExt, extData[0],
&extData[1]) == GIF_ERROR) {
#else
if (GIF_ERROR == GifAddExtensionBlock(&saveExt.ExtensionBlockCount,
&saveExt.ExtensionBlocks,
extFunction, extData[0], &extData[1])) {
#endif
return gif_error("Could not add extension block.\n", kIncompleteInput);
}
// Move to the next block
if (GIF_ERROR == DGifGetExtensionNext(gif, &extData)) {
return gif_error("Could not get next extension.\n", kIncompleteInput);
}
}
break;
// Signals the end of the gif file
case TERMINATE_RECORD_TYPE:
break;
default:
// DGifGetRecordType returns an error if the record type does
// not match one of the above cases. This should not be
// reached.
SkASSERT(false);
break;
}
} while (TERMINATE_RECORD_TYPE != recordType);
return gif_error("Could not find any images to decode in gif file.\n", kInvalidInput);
}
bool SkGifCodec::GetDimensions(GifFileType* gif, SkISize* size, SkIRect* frameRect) {
// Get the encoded dimension values
SavedImage* image = &gif->SavedImages[gif->ImageCount - 1];
const GifImageDesc& desc = image->ImageDesc;
int frameLeft = desc.Left;
int frameTop = desc.Top;
int frameWidth = desc.Width;
int frameHeight = desc.Height;
int width = gif->SWidth;
int height = gif->SHeight;
// Ensure that the decode dimensions are large enough to contain the frame
width = SkTMax(width, frameWidth + frameLeft);
height = SkTMax(height, frameHeight + frameTop);
// All of these dimensions should be positive, as they are encoded as unsigned 16-bit integers.
// It is unclear why giflib casts them to ints. We will go ahead and check that they are
// in fact positive.
if (frameLeft < 0 || frameTop < 0 || frameWidth < 0 || frameHeight < 0 || width <= 0 ||
height <= 0) {
return false;
}
frameRect->setXYWH(frameLeft, frameTop, frameWidth, frameHeight);
size->set(width, height);
return true;
}
static void Icon2Gif(char *FileName, FILE *txtin, int fdout)
{
unsigned int ExtCode, ColorMapSize = 0;
GifColorType GlobalColorMap[256], LocalColorMap[256],
*ColorMap = GlobalColorMap;
char GlobalColorKeys[PRINTABLES], LocalColorKeys[PRINTABLES],
*KeyTable = GlobalColorKeys;
int red, green, blue;
char buf[BUFSIZ * 2], InclusionFile[64];
GifFileType *GifFileOut;
SavedImage *NewImage = NULL;
int n, LineNum = 0;
if ((GifFileOut = EGifOpenFileHandle(fdout)) == NULL) {
(void) HandleGifError(GifFileOut);
}
/* OK, interpret directives */
while (fgets(buf, sizeof(buf), txtin) != (char *)NULL)
{
char *cp;
++LineNum;
/*
* Skip lines consisting only of whitespace and comments
*/
for (cp = buf; isspace((int)(*cp)); cp++)
continue;
if (*cp == '#' || *cp == '\0')
continue;
/*
* If there's a trailing comment, nuke it and all preceding whitespace.
* But preserve the EOL.
*/
if ((cp = strchr(buf, '#')) && (cp == strrchr(cp, '#')))
{
while (isspace((int)(*--cp)))
continue;
*++cp = '\n';
*++cp = '\0';
}
/*
* Explicit header declarations
*/
if (sscanf(buf, "screen width %d\n", &GifFileOut->SWidth) == 1)
continue;
else if (sscanf(buf, "screen height %d\n", &GifFileOut->SHeight) == 1)
continue;
else if (sscanf(buf, "screen colors %d\n", &n) == 1)
{
int ResBits = BitSize(n);
if (n > 256 || n < 0 || n != (1 << ResBits))
{
PARSE_ERROR("Invalid color resolution value.");
exit(EXIT_FAILURE);
}
GifFileOut->SColorResolution = ResBits;
continue;
}
else if (sscanf(buf,
"screen background %d\n",
&GifFileOut->SBackGroundColor) == 1)
continue;
/*
* Color table parsing
*/
else if (strcmp(buf, "screen map\n") == 0)
{
if (GifFileOut->SColorMap != NULL)
{
PARSE_ERROR("You've already declared a global color map.");
exit(EXIT_FAILURE);
}
ColorMapSize = 0;
ColorMap = GlobalColorMap;
KeyTable = GlobalColorKeys;
memset(GlobalColorKeys, '\0', sizeof(GlobalColorKeys));
}
else if (strcmp(buf, "image map\n") == 0)
{
if (NewImage == NULL)
{
PARSE_ERROR("No previous image declaration.");
exit(EXIT_FAILURE);
}
ColorMapSize = 0;
ColorMap = LocalColorMap;
KeyTable = LocalColorKeys;
memset(LocalColorKeys, '\0', sizeof(LocalColorKeys));
}
else if (sscanf(buf, " rgb %d %d %d is %c",
&red, &green, &blue, &KeyTable[ColorMapSize]) == 4)
{
ColorMap[ColorMapSize].Red = red;
ColorMap[ColorMapSize].Green = green;
ColorMap[ColorMapSize].Blue = blue;
ColorMapSize++;
}
else if (strcmp(buf, "end\n") == 0)
{
ColorMapObject *NewMap;
NewMap = MakeMapObject(1 << BitSize(ColorMapSize), ColorMap);
if (NewMap == (ColorMapObject *)NULL)
{
PARSE_ERROR("Out of memory while allocating new color map.");
exit(EXIT_FAILURE);
}
if (NewImage)
NewImage->ImageDesc.ColorMap = NewMap;
else
GifFileOut->SColorMap = NewMap;
}
/* GIF inclusion */
else if (sscanf(buf, "include %s", InclusionFile) == 1)
{
GifBooleanType DoTranslation;
GifPixelType Translation[256];
GifFileType *Inclusion;
SavedImage *NewImage, *CopyFrom;
if ((Inclusion = DGifOpenFileName(InclusionFile)) == NULL
|| DGifSlurp(Inclusion) == GIF_ERROR)
{
PARSE_ERROR("Inclusion read failed.");
QuitGifError(Inclusion, GifFileOut);
}
if ((DoTranslation = (GifFileOut->SColorMap!=(ColorMapObject*)NULL)))
{
ColorMapObject *UnionMap;
UnionMap = UnionColorMap(GifFileOut->SColorMap,
Inclusion->SColorMap, Translation);
if (UnionMap == NULL)
{
PARSE_ERROR("Inclusion failed --- global map conflict.");
QuitGifError(Inclusion, GifFileOut);
}
FreeMapObject(GifFileOut->SColorMap);
GifFileOut->SColorMap = UnionMap;
}
for (CopyFrom = Inclusion->SavedImages;
CopyFrom < Inclusion->SavedImages + Inclusion->ImageCount;
CopyFrom++)
{
if ((NewImage = MakeSavedImage(GifFileOut, CopyFrom)) == NULL)
{
PARSE_ERROR("Inclusion failed --- out of memory.");
QuitGifError(Inclusion, GifFileOut);
}
else if (DoTranslation)
ApplyTranslation(NewImage, Translation);
GifQprintf(
"%s: Image %d at (%d, %d) [%dx%d]: from %s\n",
PROGRAM_NAME, GifFileOut->ImageCount,
NewImage->ImageDesc.Left, NewImage->ImageDesc.Top,
NewImage->ImageDesc.Width, NewImage->ImageDesc.Height,
InclusionFile);
}
(void) DGifCloseFile(Inclusion);
}
/*
* Explicit image declarations
*/
else if (strcmp(buf, "image\n") == 0)
{
if ((NewImage = MakeSavedImage(GifFileOut, NULL)) == (SavedImage *)NULL)
{
PARSE_ERROR("Out of memory while allocating image block.");
exit(EXIT_FAILURE);
}
/* use global table unless user specifies a local one */
ColorMap = GlobalColorMap;
KeyTable = GlobalColorKeys;
}
/*
* Nothing past this point is valid unless we've seen a previous
* image declaration.
*/
else if (NewImage == (SavedImage *)NULL)
{
(void) fputs(buf, stderr);
PARSE_ERROR("Syntax error in header block.");
exit(EXIT_FAILURE);
}
/*
* Accept image attributes
*/
else if (sscanf(buf, "image top %d\n", &NewImage->ImageDesc.Top) == 1)
continue;
else if (sscanf(buf, "image left %d\n", &NewImage->ImageDesc.Left)== 1)
continue;
else if (strcmp(buf, "image interlaced\n") == 0)
{
NewImage->ImageDesc.Interlace = TRUE;
continue;
}
else if (sscanf(buf,
"image bits %d by %d\n",
&NewImage->ImageDesc.Width,
&NewImage->ImageDesc.Height) == 2)
{
int i, j;
static GifPixelType *Raster, *cp;
int c;
if ((Raster = (GifPixelType *) malloc(sizeof(GifPixelType) * NewImage->ImageDesc.Width * NewImage->ImageDesc.Height))
== NULL) {
PARSE_ERROR("Failed to allocate raster block, aborted.");
exit(EXIT_FAILURE);
}
if (!GifQuietPrint)
fprintf(stderr, "%s: Image %d at (%d, %d) [%dx%d]: ",
PROGRAM_NAME, GifFileOut->ImageCount,
NewImage->ImageDesc.Left, NewImage->ImageDesc.Top,
NewImage->ImageDesc.Width, NewImage->ImageDesc.Height);
cp = Raster;
for (i = 0; i < NewImage->ImageDesc.Height; i++) {
char *dp;
for (j = 0; j < NewImage->ImageDesc.Width; j++)
if ((c = fgetc(txtin)) == EOF) {
PARSE_ERROR("input file ended prematurely.");
exit(EXIT_FAILURE);
}
else if (c == '\n')
{
--j;
++LineNum;
}
else if (isspace(c))
--j;
else if ((dp = strchr(KeyTable, c)))
*cp++ = (dp - KeyTable);
else {
PARSE_ERROR("Invalid pixel value.");
exit(EXIT_FAILURE);
}
if (!GifQuietPrint)
fprintf(stderr, "\b\b\b\b%-4d", i);
}
if (!GifQuietPrint)
putc('\n', stderr);
NewImage->RasterBits = (unsigned char *) Raster;
}
else if (sscanf(buf, "comment"))
{
MakeExtension(NewImage, COMMENT_EXT_FUNC_CODE);
while (fgets(buf, sizeof(buf), txtin) != (char *)NULL)
if (strcmp(buf, "end\n") == 0)
break;
else
{
int Len;
buf[strlen(buf) - 1] = '\0';
Len = EscapeString(buf, buf);
if (AddExtensionBlock(NewImage, Len, (unsigned char *)buf) == GIF_ERROR) {
PARSE_ERROR("out of memory while adding comment block.");
exit(EXIT_FAILURE);
}
}
}
else if (sscanf(buf, "plaintext"))
{
MakeExtension(NewImage, PLAINTEXT_EXT_FUNC_CODE);
while (fgets(buf, sizeof(buf), txtin) != (char *)NULL)
if (strcmp(buf, "end\n") == 0)
break;
else
{
int Len;
buf[strlen(buf) - 1] = '\0';
Len = EscapeString(buf, buf);
if (AddExtensionBlock(NewImage, Len, (unsigned char *)buf) == GIF_ERROR) {
PARSE_ERROR("out of memory while adding plaintext block.");
exit(EXIT_FAILURE);
}
}
}
else if (sscanf(buf, "extension %02x", &ExtCode))
{
MakeExtension(NewImage, ExtCode);
while (fgets(buf, sizeof(buf), txtin) != (char *)NULL)
if (strcmp(buf, "end\n") == 0)
break;
else
{
int Len;
buf[strlen(buf) - 1] = '\0';
Len = EscapeString(buf, buf);
if (AddExtensionBlock(NewImage, Len, (unsigned char *)buf) == GIF_ERROR) {
PARSE_ERROR("out of memory while adding extension block.");
exit(EXIT_FAILURE);
}
}
}
else
{
(void) fputs(buf, stderr);
PARSE_ERROR("Syntax error in image description.");
exit(EXIT_FAILURE);
}
}
if (EGifSpew(GifFileOut) == GIF_ERROR)
HandleGifError(GifFileOut);
}
int
image_gif_load(image *im)
{
int x, y, ofs;
GifRecordType RecordType;
GifPixelType *line = NULL;
int ExtFunction = 0;
GifByteType *ExtData;
SavedImage *sp;
SavedImage temp_save;
int BackGround = 0;
int trans_index = 0; // transparent index if any
ColorMapObject *ColorMap;
GifColorType *ColorMapEntry;
temp_save.ExtensionBlocks = NULL;
temp_save.ExtensionBlockCount = 0;
// If reusing the object a second time, start over
if (im->used) {
DEBUG_TRACE("Recreating giflib objects\n");
image_gif_finish(im);
if (im->fh != NULL) {
// reset file to begining of image
PerlIO_seek(im->fh, im->image_offset, SEEK_SET);
}
else {
// reset SV read
im->sv_offset = im->image_offset;
}
buffer_clear(im->buf);
image_gif_read_header(im);
}
do {
if (DGifGetRecordType(im->gif, &RecordType) == GIF_ERROR) {
warn("Image::Scale unable to read GIF file (%s)\n", SvPVX(im->path));
image_gif_finish(im);
return 0;
}
switch (RecordType) {
case IMAGE_DESC_RECORD_TYPE:
if (DGifGetImageDesc(im->gif) == GIF_ERROR) {
warn("Image::Scale unable to read GIF file (%s)\n", SvPVX(im->path));
image_gif_finish(im);
return 0;
}
sp = &im->gif->SavedImages[im->gif->ImageCount - 1];
im->width = sp->ImageDesc.Width;
im->height = sp->ImageDesc.Height;
BackGround = im->gif->SBackGroundColor; // XXX needed?
ColorMap = im->gif->Image.ColorMap ? im->gif->Image.ColorMap : im->gif->SColorMap;
if (ColorMap == NULL) {
warn("Image::Scale GIF image has no colormap (%s)\n", SvPVX(im->path));
image_gif_finish(im);
return 0;
}
// Allocate storage for decompressed image
image_alloc(im, im->width, im->height);
New(0, line, im->width, GifPixelType);
if (im->gif->Image.Interlace) {
int i;
for (i = 0; i < 4; i++) {
for (x = InterlacedOffset[i]; x < im->height; x += InterlacedJumps[i]) {
ofs = x * im->width;
if (DGifGetLine(im->gif, line, 0) != GIF_OK) {
warn("Image::Scale unable to read GIF file (%s)\n", SvPVX(im->path));
image_gif_finish(im);
return 0;
}
for (y = 0; y < im->width; y++) {
ColorMapEntry = &ColorMap->Colors[line[y]];
im->pixbuf[ofs++] = COL_FULL(
ColorMapEntry->Red,
ColorMapEntry->Green,
ColorMapEntry->Blue,
trans_index == line[y] ? 0 : 255
);
}
}
}
}
else {
ofs = 0;
for (x = 0; x < im->height; x++) {
if (DGifGetLine(im->gif, line, 0) != GIF_OK) {
warn("Image::Scale unable to read GIF file (%s)\n", SvPVX(im->path));
image_gif_finish(im);
return 0;
}
for (y = 0; y < im->width; y++) {
ColorMapEntry = &ColorMap->Colors[line[y]];
im->pixbuf[ofs++] = COL_FULL(
ColorMapEntry->Red,
ColorMapEntry->Green,
ColorMapEntry->Blue,
trans_index == line[y] ? 0 : 255
);
}
}
}
Safefree(line);
break;
case EXTENSION_RECORD_TYPE:
if (DGifGetExtension(im->gif, &ExtFunction, &ExtData) == GIF_ERROR) {
warn("Image::Scale unable to read GIF file (%s)\n", SvPVX(im->path));
image_gif_finish(im);
return 0;
}
if (ExtFunction == 0xF9) { // transparency info
if (ExtData[1] & 1)
trans_index = ExtData[4];
else
trans_index = -1;
im->has_alpha = 1;
DEBUG_TRACE("GIF transparency index: %d\n", trans_index);
}
while (ExtData != NULL) {
/* Create an extension block with our data */
#ifdef GIFLIB_API_50
if (GifAddExtensionBlock(&im->gif->ExtensionBlockCount, &im->gif->ExtensionBlocks, ExtFunction, ExtData[0], &ExtData[1]) == GIF_ERROR) {
#else
temp_save.Function = ExtFunction;
if (AddExtensionBlock(&temp_save, ExtData[0], &ExtData[1]) == GIF_ERROR) {
#endif
#ifdef GIFLIB_API_41
PrintGifError();
#endif
warn("Image::Scale unable to read GIF file (%s)\n", SvPVX(im->path));
image_gif_finish(im);
return 0;
}
if (DGifGetExtensionNext(im->gif, &ExtData) == GIF_ERROR) {
#ifdef GIFLIB_API_41
PrintGifError();
#endif
warn("Image::Scale unable to read GIF file (%s)\n", SvPVX(im->path));
image_gif_finish(im);
return 0;
}
ExtFunction = 0; // CONTINUE_EXT_FUNC_CODE
}
break;
case TERMINATE_RECORD_TYPE:
default:
break;
}
} while (RecordType != TERMINATE_RECORD_TYPE);
return 1;
}
void
image_gif_finish(image *im)
{
if (im->gif != NULL) {
#ifdef GIFLIB_API_51
if (DGifCloseFile(im->gif, NULL) != GIF_OK) {
#else
if (DGifCloseFile(im->gif) != GIF_OK) {
#endif
#ifdef GIFLIB_API_41
PrintGifError();
#endif
warn("Image::Scale unable to close GIF file (%s)\n", SvPVX(im->path));
}
im->gif = NULL;
DEBUG_TRACE("image_gif_finish\n");
}
}
/******************************************************************************
* This routine reads an entire GIF into core, hanging all its state info off
* the GifFileType pointer. Call DGifOpenFileName() or DGifOpenFileHandle()
* first to initialize I/O. Its inverse is EGifSpew().
******************************************************************************/
int
DGifSlurp(GifFileType * GifFile) {
int ImageSize;
GifRecordType RecordType;
SavedImage *sp;
GifByteType *ExtData;
Extensions temp_save;
temp_save.ExtensionBlocks = NULL;
temp_save.ExtensionBlockCount = 0;
do {
if (DGifGetRecordType(GifFile, &RecordType) == GIF_ERROR)
return (GIF_ERROR);
switch (RecordType) {
case IMAGE_DESC_RECORD_TYPE:
if (DGifGetImageDesc(GifFile) == GIF_ERROR)
return (GIF_ERROR);
sp = &GifFile->SavedImages[GifFile->ImageCount - 1];
ImageSize = sp->ImageDesc.Width * sp->ImageDesc.Height;
sp->RasterBits = ungif_alloc(ImageSize * sizeof(GifPixelType));
if (sp->RasterBits == NULL) {
return GIF_ERROR;
}
if (DGifGetLine(GifFile, sp->RasterBits, ImageSize) ==
GIF_ERROR)
return (GIF_ERROR);
if (temp_save.ExtensionBlocks) {
sp->Extensions.ExtensionBlocks = temp_save.ExtensionBlocks;
sp->Extensions.ExtensionBlockCount = temp_save.ExtensionBlockCount;
temp_save.ExtensionBlocks = NULL;
temp_save.ExtensionBlockCount = 0;
/* FIXME: The following is wrong. It is left in only for
* backwards compatibility. Someday it should go away. Use
* the sp->ExtensionBlocks->Function variable instead. */
sp->Extensions.Function = sp->Extensions.ExtensionBlocks[0].Function;
}
break;
case EXTENSION_RECORD_TYPE:
{
int Function;
Extensions *Extensions;
if (DGifGetExtension(GifFile, &Function, &ExtData) == GIF_ERROR)
return (GIF_ERROR);
if (GifFile->ImageCount || Function == GRAPHICS_EXT_FUNC_CODE)
Extensions = &temp_save;
else
Extensions = &GifFile->Extensions;
Extensions->Function = Function;
/* Create an extension block with our data */
if (AddExtensionBlock(Extensions, ExtData[0], &ExtData[1]) == GIF_ERROR)
return (GIF_ERROR);
while (ExtData != NULL) {
int Len;
GifByteType *Data;
if (DGifGetExtensionNext(GifFile, &ExtData) == GIF_ERROR)
return (GIF_ERROR);
if (ExtData)
{
Len = ExtData[0];
Data = &ExtData[1];
}
else
{
Len = 0;
Data = NULL;
}
if (AppendExtensionBlock(Extensions, Len, Data) == GIF_ERROR)
return (GIF_ERROR);
}
break;
}
case TERMINATE_RECORD_TYPE:
break;
default: /* Should be trapped by DGifGetRecordType */
break;
}
} while (RecordType != TERMINATE_RECORD_TYPE);
/* Just in case the Gif has an extension block without an associated
* image... (Should we save this into a savefile structure with no image
* instead? Have to check if the present writing code can handle that as
* well.... */
if (temp_save.ExtensionBlocks)
FreeExtension(&temp_save);
return (GIF_OK);
}
