mirror of
https://github.com/Redot-Engine/redot-engine.git
synced 2025-12-06 07:17:42 -05:00
614048d3ee
Add GIF file loading Add `ResourceFormatLoader` for `SpriteFrames` Add `ResourceFormatLoader` for `AnimatedTexture` Add `ImageFrames` resource for handling image sequence Add `ImageFramesLoader` for resource loading image sequences Add `ResourceFormatLoader` for `ImageFrames` Add GIF image load test assertions Add ImageFrames test cases
1313 lines
40 KiB
C
1313 lines
40 KiB
C
/******************************************************************************
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dgif_lib.c - GIF decoding
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The functions here and in egif_lib.c are partitioned carefully so that
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if you only require one of read and write capability, only one of these
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two modules will be linked. Preserve this property!
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SPDX-License-Identifier: MIT
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*****************************************************************************/
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#include <fcntl.h>
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#include <limits.h>
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#include <stdint.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#ifdef _WIN32
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#include <io.h>
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#else
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#include <unistd.h>
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#endif /* _WIN32 */
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#include "gif_lib.h"
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#include "gif_lib_private.h"
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/* compose unsigned little endian value */
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#define UNSIGNED_LITTLE_ENDIAN(lo, hi) ((lo) | ((hi) << 8))
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/* avoid extra function call in case we use fread (TVT) */
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static int InternalRead(GifFileType *gif, GifByteType *buf, int len) {
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// fprintf(stderr, "### Read: %d\n", len);
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return (((GifFilePrivateType *)gif->Private)->Read
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? ((GifFilePrivateType *)gif->Private)->Read(gif, buf, len)
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: fread(buf, 1, len,
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((GifFilePrivateType *)gif->Private)->File));
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}
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static int DGifGetWord(GifFileType *GifFile, GifWord *Word);
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static int DGifSetupDecompress(GifFileType *GifFile);
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static int DGifDecompressLine(GifFileType *GifFile, GifPixelType *Line,
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int LineLen);
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static int DGifGetPrefixChar(const GifPrefixType *Prefix, int Code,
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int ClearCode);
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static int DGifDecompressInput(GifFileType *GifFile, int *Code);
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static int DGifBufferedInput(GifFileType *GifFile, GifByteType *Buf,
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GifByteType *NextByte);
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/******************************************************************************
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Open a new GIF file for read, given by its name.
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Returns dynamically allocated GifFileType pointer which serves as the GIF
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info record.
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******************************************************************************/
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GifFileType *DGifOpenFileName(const char *FileName, int *Error) {
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int FileHandle;
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GifFileType *GifFile;
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if ((FileHandle = open(FileName, O_RDONLY)) == -1) {
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if (Error != NULL) {
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*Error = D_GIF_ERR_OPEN_FAILED;
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}
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return NULL;
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}
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GifFile = DGifOpenFileHandle(FileHandle, Error);
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return GifFile;
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}
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/******************************************************************************
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Update a new GIF file, given its file handle.
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Returns dynamically allocated GifFileType pointer which serves as the GIF
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info record.
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******************************************************************************/
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GifFileType *DGifOpenFileHandle(int FileHandle, int *Error) {
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char Buf[GIF_STAMP_LEN + 1];
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GifFileType *GifFile;
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GifFilePrivateType *Private;
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FILE *f;
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GifFile = (GifFileType *)malloc(sizeof(GifFileType));
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if (GifFile == NULL) {
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if (Error != NULL) {
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*Error = D_GIF_ERR_NOT_ENOUGH_MEM;
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}
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(void)close(FileHandle);
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return NULL;
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}
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/*@i1@*/ memset(GifFile, '\0', sizeof(GifFileType));
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/* Belt and suspenders, in case the null pointer isn't zero */
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GifFile->SavedImages = NULL;
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GifFile->SColorMap = NULL;
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Private = (GifFilePrivateType *)calloc(1, sizeof(GifFilePrivateType));
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if (Private == NULL) {
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if (Error != NULL) {
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*Error = D_GIF_ERR_NOT_ENOUGH_MEM;
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}
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(void)close(FileHandle);
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free((char *)GifFile);
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return NULL;
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}
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/*@i1@*/ memset(Private, '\0', sizeof(GifFilePrivateType));
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#ifdef _WIN32
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_setmode(FileHandle, O_BINARY); /* Make sure it is in binary mode. */
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#endif /* _WIN32 */
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f = fdopen(FileHandle, "rb"); /* Make it into a stream: */
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/*@-mustfreeonly@*/
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GifFile->Private = (void *)Private;
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Private->FileHandle = FileHandle;
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Private->File = f;
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Private->FileState = FILE_STATE_READ;
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Private->Read = NULL; /* don't use alternate input method (TVT) */
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GifFile->UserData = NULL; /* TVT */
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/*@=mustfreeonly@*/
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/* Let's see if this is a GIF file: */
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/* coverity[check_return] */
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if (InternalRead(GifFile, (unsigned char *)Buf, GIF_STAMP_LEN) !=
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GIF_STAMP_LEN) {
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if (Error != NULL) {
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*Error = D_GIF_ERR_READ_FAILED;
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}
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(void)fclose(f);
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free((char *)Private);
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free((char *)GifFile);
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return NULL;
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}
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/* Check for GIF prefix at start of file */
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Buf[GIF_STAMP_LEN] = 0;
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if (strncmp(GIF_STAMP, Buf, GIF_VERSION_POS) != 0) {
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if (Error != NULL) {
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*Error = D_GIF_ERR_NOT_GIF_FILE;
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}
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(void)fclose(f);
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free((char *)Private);
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free((char *)GifFile);
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return NULL;
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}
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if (DGifGetScreenDesc(GifFile) == GIF_ERROR) {
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(void)fclose(f);
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free((char *)Private);
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free((char *)GifFile);
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return NULL;
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}
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GifFile->Error = 0;
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/* What version of GIF? */
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Private->gif89 = (Buf[GIF_VERSION_POS + 1] == '9');
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return GifFile;
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}
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/******************************************************************************
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GifFileType constructor with user supplied input function (TVT)
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******************************************************************************/
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GifFileType *DGifOpen(void *userData, InputFunc readFunc, int *Error) {
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char Buf[GIF_STAMP_LEN + 1];
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GifFileType *GifFile;
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GifFilePrivateType *Private;
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GifFile = (GifFileType *)malloc(sizeof(GifFileType));
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if (GifFile == NULL) {
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if (Error != NULL) {
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*Error = D_GIF_ERR_NOT_ENOUGH_MEM;
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}
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return NULL;
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}
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memset(GifFile, '\0', sizeof(GifFileType));
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/* Belt and suspenders, in case the null pointer isn't zero */
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GifFile->SavedImages = NULL;
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GifFile->SColorMap = NULL;
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Private = (GifFilePrivateType *)calloc(1, sizeof(GifFilePrivateType));
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if (!Private) {
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if (Error != NULL) {
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*Error = D_GIF_ERR_NOT_ENOUGH_MEM;
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}
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free((char *)GifFile);
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return NULL;
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}
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/*@i1@*/ memset(Private, '\0', sizeof(GifFilePrivateType));
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GifFile->Private = (void *)Private;
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Private->FileHandle = 0;
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Private->File = NULL;
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Private->FileState = FILE_STATE_READ;
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Private->Read = readFunc; /* TVT */
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GifFile->UserData = userData; /* TVT */
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/* Lets see if this is a GIF file: */
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/* coverity[check_return] */
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if (InternalRead(GifFile, (unsigned char *)Buf, GIF_STAMP_LEN) !=
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GIF_STAMP_LEN) {
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if (Error != NULL) {
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*Error = D_GIF_ERR_READ_FAILED;
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}
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free((char *)Private);
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free((char *)GifFile);
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return NULL;
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}
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/* Check for GIF prefix at start of file */
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Buf[GIF_STAMP_LEN] = '\0';
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if (strncmp(GIF_STAMP, Buf, GIF_VERSION_POS) != 0) {
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if (Error != NULL) {
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*Error = D_GIF_ERR_NOT_GIF_FILE;
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}
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free((char *)Private);
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free((char *)GifFile);
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return NULL;
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}
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if (DGifGetScreenDesc(GifFile) == GIF_ERROR) {
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free((char *)Private);
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free((char *)GifFile);
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if (Error != NULL) {
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*Error = D_GIF_ERR_NO_SCRN_DSCR;
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}
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return NULL;
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}
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GifFile->Error = 0;
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/* What version of GIF? */
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Private->gif89 = (Buf[GIF_VERSION_POS + 1] == '9');
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return GifFile;
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}
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/******************************************************************************
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This routine should be called before any other DGif calls. Note that
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this routine is called automatically from DGif file open routines.
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******************************************************************************/
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int DGifGetScreenDesc(GifFileType *GifFile) {
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int BitsPerPixel;
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bool SortFlag;
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GifByteType Buf[3];
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GifFilePrivateType *Private = (GifFilePrivateType *)GifFile->Private;
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if (!IS_READABLE(Private)) {
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/* This file was NOT open for reading: */
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GifFile->Error = D_GIF_ERR_NOT_READABLE;
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return GIF_ERROR;
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}
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/* Put the screen descriptor into the file: */
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if (DGifGetWord(GifFile, &GifFile->SWidth) == GIF_ERROR ||
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DGifGetWord(GifFile, &GifFile->SHeight) == GIF_ERROR) {
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return GIF_ERROR;
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}
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if (InternalRead(GifFile, Buf, 3) != 3) {
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GifFile->Error = D_GIF_ERR_READ_FAILED;
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GifFreeMapObject(GifFile->SColorMap);
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GifFile->SColorMap = NULL;
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return GIF_ERROR;
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}
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GifFile->SColorResolution = (((Buf[0] & 0x70) + 1) >> 4) + 1;
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SortFlag = (Buf[0] & 0x08) != 0;
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BitsPerPixel = (Buf[0] & 0x07) + 1;
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GifFile->SBackGroundColor = Buf[1];
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GifFile->AspectByte = Buf[2];
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if (Buf[0] & 0x80) { /* Do we have global color map? */
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int i;
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GifFile->SColorMap = GifMakeMapObject(1 << BitsPerPixel, NULL);
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if (GifFile->SColorMap == NULL) {
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GifFile->Error = D_GIF_ERR_NOT_ENOUGH_MEM;
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return GIF_ERROR;
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}
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/* Get the global color map: */
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GifFile->SColorMap->SortFlag = SortFlag;
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for (i = 0; i < GifFile->SColorMap->ColorCount; i++) {
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/* coverity[check_return] */
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if (InternalRead(GifFile, Buf, 3) != 3) {
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GifFreeMapObject(GifFile->SColorMap);
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GifFile->SColorMap = NULL;
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GifFile->Error = D_GIF_ERR_READ_FAILED;
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return GIF_ERROR;
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}
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GifFile->SColorMap->Colors[i].Red = Buf[0];
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GifFile->SColorMap->Colors[i].Green = Buf[1];
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GifFile->SColorMap->Colors[i].Blue = Buf[2];
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}
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} else {
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GifFile->SColorMap = NULL;
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}
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/*
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* No check here for whether the background color is in range for the
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* screen color map. Possibly there should be.
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*/
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return GIF_OK;
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}
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const char *DGifGetGifVersion(GifFileType *GifFile) {
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GifFilePrivateType *Private = (GifFilePrivateType *)GifFile->Private;
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if (Private->gif89) {
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return GIF89_STAMP;
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} else {
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return GIF87_STAMP;
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}
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}
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/******************************************************************************
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This routine should be called before any attempt to read an image.
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******************************************************************************/
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int DGifGetRecordType(GifFileType *GifFile, GifRecordType *Type) {
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GifByteType Buf;
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GifFilePrivateType *Private = (GifFilePrivateType *)GifFile->Private;
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if (!IS_READABLE(Private)) {
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/* This file was NOT open for reading: */
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GifFile->Error = D_GIF_ERR_NOT_READABLE;
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return GIF_ERROR;
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}
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/* coverity[check_return] */
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if (InternalRead(GifFile, &Buf, 1) != 1) {
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GifFile->Error = D_GIF_ERR_READ_FAILED;
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return GIF_ERROR;
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}
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// fprintf(stderr, "### DGifGetRecordType: %02x\n", Buf);
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switch (Buf) {
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case DESCRIPTOR_INTRODUCER:
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*Type = IMAGE_DESC_RECORD_TYPE;
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break;
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case EXTENSION_INTRODUCER:
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*Type = EXTENSION_RECORD_TYPE;
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break;
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case TERMINATOR_INTRODUCER:
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*Type = TERMINATE_RECORD_TYPE;
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break;
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default:
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*Type = UNDEFINED_RECORD_TYPE;
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GifFile->Error = D_GIF_ERR_WRONG_RECORD;
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return GIF_ERROR;
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}
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return GIF_OK;
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}
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int DGifGetImageHeader(GifFileType *GifFile) {
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unsigned int BitsPerPixel;
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GifByteType Buf[3];
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GifFilePrivateType *Private = (GifFilePrivateType *)GifFile->Private;
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if (!IS_READABLE(Private)) {
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/* This file was NOT open for reading: */
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GifFile->Error = D_GIF_ERR_NOT_READABLE;
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return GIF_ERROR;
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}
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if (DGifGetWord(GifFile, &GifFile->Image.Left) == GIF_ERROR ||
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DGifGetWord(GifFile, &GifFile->Image.Top) == GIF_ERROR ||
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DGifGetWord(GifFile, &GifFile->Image.Width) == GIF_ERROR ||
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DGifGetWord(GifFile, &GifFile->Image.Height) == GIF_ERROR) {
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return GIF_ERROR;
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}
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if (InternalRead(GifFile, Buf, 1) != 1) {
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GifFile->Error = D_GIF_ERR_READ_FAILED;
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GifFreeMapObject(GifFile->Image.ColorMap);
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GifFile->Image.ColorMap = NULL;
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return GIF_ERROR;
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}
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BitsPerPixel = (Buf[0] & 0x07) + 1;
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GifFile->Image.Interlace = (Buf[0] & 0x40) ? true : false;
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/* Setup the colormap */
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if (GifFile->Image.ColorMap) {
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GifFreeMapObject(GifFile->Image.ColorMap);
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GifFile->Image.ColorMap = NULL;
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}
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/* Does this image have local color map? */
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if (Buf[0] & 0x80) {
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unsigned int i;
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GifFile->Image.ColorMap =
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GifMakeMapObject(1 << BitsPerPixel, NULL);
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if (GifFile->Image.ColorMap == NULL) {
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GifFile->Error = D_GIF_ERR_NOT_ENOUGH_MEM;
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return GIF_ERROR;
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}
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/* Get the image local color map: */
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for (i = 0; i < GifFile->Image.ColorMap->ColorCount; i++) {
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/* coverity[check_return] */
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if (InternalRead(GifFile, Buf, 3) != 3) {
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GifFreeMapObject(GifFile->Image.ColorMap);
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GifFile->Error = D_GIF_ERR_READ_FAILED;
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GifFile->Image.ColorMap = NULL;
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return GIF_ERROR;
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}
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GifFile->Image.ColorMap->Colors[i].Red = Buf[0];
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GifFile->Image.ColorMap->Colors[i].Green = Buf[1];
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GifFile->Image.ColorMap->Colors[i].Blue = Buf[2];
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}
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}
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Private->PixelCount =
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(long)GifFile->Image.Width * (long)GifFile->Image.Height;
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/* Reset decompress algorithm parameters. */
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return DGifSetupDecompress(GifFile);
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}
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/******************************************************************************
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This routine should be called before any attempt to read an image.
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Note it is assumed the Image desc. header has been read.
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******************************************************************************/
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int DGifGetImageDesc(GifFileType *GifFile) {
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GifFilePrivateType *Private = (GifFilePrivateType *)GifFile->Private;
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SavedImage *sp;
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if (!IS_READABLE(Private)) {
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/* This file was NOT open for reading: */
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GifFile->Error = D_GIF_ERR_NOT_READABLE;
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return GIF_ERROR;
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}
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if (DGifGetImageHeader(GifFile) == GIF_ERROR) {
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return GIF_ERROR;
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}
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if (GifFile->SavedImages) {
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SavedImage *new_saved_images = (SavedImage *)reallocarray(
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GifFile->SavedImages, (GifFile->ImageCount + 1),
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sizeof(SavedImage));
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if (new_saved_images == NULL) {
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GifFile->Error = D_GIF_ERR_NOT_ENOUGH_MEM;
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return GIF_ERROR;
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}
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GifFile->SavedImages = new_saved_images;
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} else {
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if ((GifFile->SavedImages =
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(SavedImage *)malloc(sizeof(SavedImage))) == NULL) {
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GifFile->Error = D_GIF_ERR_NOT_ENOUGH_MEM;
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return GIF_ERROR;
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}
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}
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sp = &GifFile->SavedImages[GifFile->ImageCount];
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memcpy(&sp->ImageDesc, &GifFile->Image, sizeof(GifImageDesc));
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if (GifFile->Image.ColorMap != NULL) {
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sp->ImageDesc.ColorMap =
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GifMakeMapObject(GifFile->Image.ColorMap->ColorCount,
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GifFile->Image.ColorMap->Colors);
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if (sp->ImageDesc.ColorMap == NULL) {
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GifFile->Error = D_GIF_ERR_NOT_ENOUGH_MEM;
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return GIF_ERROR;
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}
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}
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sp->RasterBits = (unsigned char *)NULL;
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sp->ExtensionBlockCount = 0;
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sp->ExtensionBlocks = (ExtensionBlock *)NULL;
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GifFile->ImageCount++;
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return GIF_OK;
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}
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/******************************************************************************
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Get one full scanned line (Line) of length LineLen from GIF file.
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******************************************************************************/
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int DGifGetLine(GifFileType *GifFile, GifPixelType *Line, int LineLen) {
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GifByteType *Dummy;
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GifFilePrivateType *Private = (GifFilePrivateType *)GifFile->Private;
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if (!IS_READABLE(Private)) {
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/* This file was NOT open for reading: */
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GifFile->Error = D_GIF_ERR_NOT_READABLE;
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return GIF_ERROR;
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}
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|
|
if (!LineLen) {
|
|
LineLen = GifFile->Image.Width;
|
|
}
|
|
|
|
if ((Private->PixelCount -= LineLen) > 0xffff0000UL) {
|
|
GifFile->Error = D_GIF_ERR_DATA_TOO_BIG;
|
|
return GIF_ERROR;
|
|
}
|
|
|
|
if (DGifDecompressLine(GifFile, Line, LineLen) == GIF_OK) {
|
|
if (Private->PixelCount == 0) {
|
|
/* We probably won't be called any more, so let's clean
|
|
* up everything before we return: need to flush out all
|
|
* the rest of image until an empty block (size 0)
|
|
* detected. We use GetCodeNext.
|
|
*/
|
|
do {
|
|
if (DGifGetCodeNext(GifFile, &Dummy) ==
|
|
GIF_ERROR) {
|
|
return GIF_ERROR;
|
|
}
|
|
} while (Dummy != NULL);
|
|
}
|
|
return GIF_OK;
|
|
} else {
|
|
return GIF_ERROR;
|
|
}
|
|
}
|
|
|
|
/******************************************************************************
|
|
Put one pixel (Pixel) into GIF file.
|
|
******************************************************************************/
|
|
int DGifGetPixel(GifFileType *GifFile, GifPixelType Pixel) {
|
|
GifByteType *Dummy;
|
|
GifFilePrivateType *Private = (GifFilePrivateType *)GifFile->Private;
|
|
|
|
if (!IS_READABLE(Private)) {
|
|
/* This file was NOT open for reading: */
|
|
GifFile->Error = D_GIF_ERR_NOT_READABLE;
|
|
return GIF_ERROR;
|
|
}
|
|
if (--Private->PixelCount > 0xffff0000UL) {
|
|
GifFile->Error = D_GIF_ERR_DATA_TOO_BIG;
|
|
return GIF_ERROR;
|
|
}
|
|
|
|
if (DGifDecompressLine(GifFile, &Pixel, 1) == GIF_OK) {
|
|
if (Private->PixelCount == 0) {
|
|
/* We probably won't be called any more, so let's clean
|
|
* up everything before we return: need to flush out all
|
|
* the rest of image until an empty block (size 0)
|
|
* detected. We use GetCodeNext.
|
|
*/
|
|
do {
|
|
if (DGifGetCodeNext(GifFile, &Dummy) ==
|
|
GIF_ERROR) {
|
|
return GIF_ERROR;
|
|
}
|
|
} while (Dummy != NULL);
|
|
}
|
|
return GIF_OK;
|
|
} else {
|
|
return GIF_ERROR;
|
|
}
|
|
}
|
|
|
|
/******************************************************************************
|
|
Get an extension block (see GIF manual) from GIF file. This routine only
|
|
returns the first data block, and DGifGetExtensionNext should be called
|
|
after this one until NULL extension is returned.
|
|
The Extension should NOT be freed by the user (not dynamically allocated).
|
|
Note it is assumed the Extension description header has been read.
|
|
******************************************************************************/
|
|
int DGifGetExtension(GifFileType *GifFile, int *ExtCode,
|
|
GifByteType **Extension) {
|
|
GifByteType Buf;
|
|
GifFilePrivateType *Private = (GifFilePrivateType *)GifFile->Private;
|
|
|
|
// fprintf(stderr, "### -> DGifGetExtension:\n");
|
|
if (!IS_READABLE(Private)) {
|
|
/* This file was NOT open for reading: */
|
|
GifFile->Error = D_GIF_ERR_NOT_READABLE;
|
|
return GIF_ERROR;
|
|
}
|
|
|
|
/* coverity[check_return] */
|
|
if (InternalRead(GifFile, &Buf, 1) != 1) {
|
|
GifFile->Error = D_GIF_ERR_READ_FAILED;
|
|
return GIF_ERROR;
|
|
}
|
|
*ExtCode = Buf;
|
|
// fprintf(stderr, "### <- DGifGetExtension: %02x, about to call
|
|
// next\n", Buf);
|
|
|
|
return DGifGetExtensionNext(GifFile, Extension);
|
|
}
|
|
|
|
/******************************************************************************
|
|
Get a following extension block (see GIF manual) from GIF file. This
|
|
routine should be called until NULL Extension is returned.
|
|
The Extension should NOT be freed by the user (not dynamically allocated).
|
|
******************************************************************************/
|
|
int DGifGetExtensionNext(GifFileType *GifFile, GifByteType **Extension) {
|
|
GifByteType Buf;
|
|
GifFilePrivateType *Private = (GifFilePrivateType *)GifFile->Private;
|
|
|
|
// fprintf(stderr, "### -> DGifGetExtensionNext\n");
|
|
if (InternalRead(GifFile, &Buf, 1) != 1) {
|
|
GifFile->Error = D_GIF_ERR_READ_FAILED;
|
|
return GIF_ERROR;
|
|
}
|
|
// fprintf(stderr, "### DGifGetExtensionNext sees %d\n", Buf);
|
|
|
|
if (Buf > 0) {
|
|
*Extension = Private->Buf; /* Use private unused buffer. */
|
|
(*Extension)[0] =
|
|
Buf; /* Pascal strings notation (pos. 0 is len.). */
|
|
/* coverity[tainted_data,check_return] */
|
|
if (InternalRead(GifFile, &((*Extension)[1]), Buf) != Buf) {
|
|
GifFile->Error = D_GIF_ERR_READ_FAILED;
|
|
return GIF_ERROR;
|
|
}
|
|
} else {
|
|
*Extension = NULL;
|
|
}
|
|
// fprintf(stderr, "### <- DGifGetExtensionNext: %p\n", Extension);
|
|
|
|
return GIF_OK;
|
|
}
|
|
|
|
/******************************************************************************
|
|
Extract a Graphics Control Block from raw extension data
|
|
******************************************************************************/
|
|
|
|
int DGifExtensionToGCB(const size_t GifExtensionLength,
|
|
const GifByteType *GifExtension,
|
|
GraphicsControlBlock *GCB) {
|
|
if (GifExtensionLength != 4) {
|
|
return GIF_ERROR;
|
|
}
|
|
|
|
GCB->DisposalMode = (GifExtension[0] >> 2) & 0x07;
|
|
GCB->UserInputFlag = (GifExtension[0] & 0x02) != 0;
|
|
GCB->DelayTime =
|
|
UNSIGNED_LITTLE_ENDIAN(GifExtension[1], GifExtension[2]);
|
|
if (GifExtension[0] & 0x01) {
|
|
GCB->TransparentColor = (int)GifExtension[3];
|
|
} else {
|
|
GCB->TransparentColor = NO_TRANSPARENT_COLOR;
|
|
}
|
|
|
|
return GIF_OK;
|
|
}
|
|
|
|
/******************************************************************************
|
|
Extract the Graphics Control Block for a saved image, if it exists.
|
|
******************************************************************************/
|
|
|
|
int DGifSavedExtensionToGCB(GifFileType *GifFile, int ImageIndex,
|
|
GraphicsControlBlock *GCB) {
|
|
int i;
|
|
|
|
if (ImageIndex < 0 || ImageIndex > GifFile->ImageCount - 1) {
|
|
return GIF_ERROR;
|
|
}
|
|
|
|
GCB->DisposalMode = DISPOSAL_UNSPECIFIED;
|
|
GCB->UserInputFlag = false;
|
|
GCB->DelayTime = 0;
|
|
GCB->TransparentColor = NO_TRANSPARENT_COLOR;
|
|
|
|
for (i = 0; i < GifFile->SavedImages[ImageIndex].ExtensionBlockCount;
|
|
i++) {
|
|
ExtensionBlock *ep =
|
|
&GifFile->SavedImages[ImageIndex].ExtensionBlocks[i];
|
|
if (ep->Function == GRAPHICS_EXT_FUNC_CODE) {
|
|
return DGifExtensionToGCB(ep->ByteCount, ep->Bytes,
|
|
GCB);
|
|
}
|
|
}
|
|
|
|
return GIF_ERROR;
|
|
}
|
|
|
|
/******************************************************************************
|
|
This routine should be called last, to close the GIF file.
|
|
******************************************************************************/
|
|
int DGifCloseFile(GifFileType *GifFile, int *ErrorCode) {
|
|
GifFilePrivateType *Private;
|
|
|
|
if (GifFile == NULL || GifFile->Private == NULL) {
|
|
return GIF_ERROR;
|
|
}
|
|
|
|
if (GifFile->Image.ColorMap) {
|
|
GifFreeMapObject(GifFile->Image.ColorMap);
|
|
GifFile->Image.ColorMap = NULL;
|
|
}
|
|
|
|
if (GifFile->SColorMap) {
|
|
GifFreeMapObject(GifFile->SColorMap);
|
|
GifFile->SColorMap = NULL;
|
|
}
|
|
|
|
if (GifFile->SavedImages) {
|
|
GifFreeSavedImages(GifFile);
|
|
GifFile->SavedImages = NULL;
|
|
}
|
|
|
|
GifFreeExtensions(&GifFile->ExtensionBlockCount,
|
|
&GifFile->ExtensionBlocks);
|
|
|
|
Private = (GifFilePrivateType *)GifFile->Private;
|
|
|
|
if (!IS_READABLE(Private)) {
|
|
/* This file was NOT open for reading: */
|
|
if (ErrorCode != NULL) {
|
|
*ErrorCode = D_GIF_ERR_NOT_READABLE;
|
|
}
|
|
free((char *)GifFile->Private);
|
|
free(GifFile);
|
|
return GIF_ERROR;
|
|
}
|
|
|
|
if (Private->File && (fclose(Private->File) != 0)) {
|
|
if (ErrorCode != NULL) {
|
|
*ErrorCode = D_GIF_ERR_CLOSE_FAILED;
|
|
}
|
|
free((char *)GifFile->Private);
|
|
free(GifFile);
|
|
return GIF_ERROR;
|
|
}
|
|
|
|
free((char *)GifFile->Private);
|
|
free(GifFile);
|
|
if (ErrorCode != NULL) {
|
|
*ErrorCode = D_GIF_SUCCEEDED;
|
|
}
|
|
return GIF_OK;
|
|
}
|
|
|
|
/******************************************************************************
|
|
Get 2 bytes (word) from the given file:
|
|
******************************************************************************/
|
|
static int DGifGetWord(GifFileType *GifFile, GifWord *Word) {
|
|
unsigned char c[2];
|
|
|
|
/* coverity[check_return] */
|
|
if (InternalRead(GifFile, c, 2) != 2) {
|
|
GifFile->Error = D_GIF_ERR_READ_FAILED;
|
|
return GIF_ERROR;
|
|
}
|
|
|
|
*Word = (GifWord)UNSIGNED_LITTLE_ENDIAN(c[0], c[1]);
|
|
return GIF_OK;
|
|
}
|
|
|
|
/******************************************************************************
|
|
Get the image code in compressed form. This routine can be called if the
|
|
information needed to be piped out as is. Obviously this is much faster
|
|
than decoding and encoding again. This routine should be followed by calls
|
|
to DGifGetCodeNext, until NULL block is returned.
|
|
The block should NOT be freed by the user (not dynamically allocated).
|
|
******************************************************************************/
|
|
int DGifGetCode(GifFileType *GifFile, int *CodeSize, GifByteType **CodeBlock) {
|
|
GifFilePrivateType *Private = (GifFilePrivateType *)GifFile->Private;
|
|
|
|
if (!IS_READABLE(Private)) {
|
|
/* This file was NOT open for reading: */
|
|
GifFile->Error = D_GIF_ERR_NOT_READABLE;
|
|
return GIF_ERROR;
|
|
}
|
|
|
|
*CodeSize = Private->BitsPerPixel;
|
|
|
|
return DGifGetCodeNext(GifFile, CodeBlock);
|
|
}
|
|
|
|
/******************************************************************************
|
|
Continue to get the image code in compressed form. This routine should be
|
|
called until NULL block is returned.
|
|
The block should NOT be freed by the user (not dynamically allocated).
|
|
******************************************************************************/
|
|
int DGifGetCodeNext(GifFileType *GifFile, GifByteType **CodeBlock) {
|
|
GifByteType Buf;
|
|
GifFilePrivateType *Private = (GifFilePrivateType *)GifFile->Private;
|
|
|
|
/* coverity[tainted_data_argument] */
|
|
/* coverity[check_return] */
|
|
if (InternalRead(GifFile, &Buf, 1) != 1) {
|
|
GifFile->Error = D_GIF_ERR_READ_FAILED;
|
|
return GIF_ERROR;
|
|
}
|
|
|
|
/* coverity[lower_bounds] */
|
|
if (Buf > 0) {
|
|
*CodeBlock = Private->Buf; /* Use private unused buffer. */
|
|
(*CodeBlock)[0] =
|
|
Buf; /* Pascal strings notation (pos. 0 is len.). */
|
|
/* coverity[tainted_data] */
|
|
if (InternalRead(GifFile, &((*CodeBlock)[1]), Buf) != Buf) {
|
|
GifFile->Error = D_GIF_ERR_READ_FAILED;
|
|
return GIF_ERROR;
|
|
}
|
|
} else {
|
|
*CodeBlock = NULL;
|
|
Private->Buf[0] = 0; /* Make sure the buffer is empty! */
|
|
Private->PixelCount =
|
|
0; /* And local info. indicate image read. */
|
|
}
|
|
|
|
return GIF_OK;
|
|
}
|
|
|
|
/******************************************************************************
|
|
Setup the LZ decompression for this image:
|
|
******************************************************************************/
|
|
static int DGifSetupDecompress(GifFileType *GifFile) {
|
|
int i, BitsPerPixel;
|
|
GifByteType CodeSize;
|
|
GifPrefixType *Prefix;
|
|
GifFilePrivateType *Private = (GifFilePrivateType *)GifFile->Private;
|
|
|
|
/* coverity[check_return] */
|
|
if (InternalRead(GifFile, &CodeSize, 1) <
|
|
1) { /* Read Code size from file. */
|
|
GifFile->Error = D_GIF_ERR_READ_FAILED;
|
|
return GIF_ERROR; /* Failed to read Code size. */
|
|
}
|
|
BitsPerPixel = CodeSize;
|
|
|
|
/* this can only happen on a severely malformed GIF */
|
|
if (BitsPerPixel > 8) {
|
|
GifFile->Error =
|
|
D_GIF_ERR_READ_FAILED; /* somewhat bogus error code */
|
|
return GIF_ERROR; /* Failed to read Code size. */
|
|
}
|
|
|
|
Private->Buf[0] = 0; /* Input Buffer empty. */
|
|
Private->BitsPerPixel = BitsPerPixel;
|
|
Private->ClearCode = (1 << BitsPerPixel);
|
|
Private->EOFCode = Private->ClearCode + 1;
|
|
Private->RunningCode = Private->EOFCode + 1;
|
|
Private->RunningBits = BitsPerPixel + 1; /* Number of bits per code. */
|
|
Private->MaxCode1 = 1 << Private->RunningBits; /* Max. code + 1. */
|
|
Private->StackPtr = 0; /* No pixels on the pixel stack. */
|
|
Private->LastCode = NO_SUCH_CODE;
|
|
Private->CrntShiftState = 0; /* No information in CrntShiftDWord. */
|
|
Private->CrntShiftDWord = 0;
|
|
|
|
Prefix = Private->Prefix;
|
|
for (i = 0; i <= LZ_MAX_CODE; i++) {
|
|
Prefix[i] = NO_SUCH_CODE;
|
|
}
|
|
|
|
return GIF_OK;
|
|
}
|
|
|
|
/******************************************************************************
|
|
The LZ decompression routine:
|
|
This version decompress the given GIF file into Line of length LineLen.
|
|
This routine can be called few times (one per scan line, for example), in
|
|
order the complete the whole image.
|
|
******************************************************************************/
|
|
static int DGifDecompressLine(GifFileType *GifFile, GifPixelType *Line,
|
|
int LineLen) {
|
|
int i = 0;
|
|
int j, CrntCode, EOFCode, ClearCode, CrntPrefix, LastCode, StackPtr;
|
|
GifByteType *Stack, *Suffix;
|
|
GifPrefixType *Prefix;
|
|
GifFilePrivateType *Private = (GifFilePrivateType *)GifFile->Private;
|
|
|
|
StackPtr = Private->StackPtr;
|
|
Prefix = Private->Prefix;
|
|
Suffix = Private->Suffix;
|
|
Stack = Private->Stack;
|
|
EOFCode = Private->EOFCode;
|
|
ClearCode = Private->ClearCode;
|
|
LastCode = Private->LastCode;
|
|
|
|
if (StackPtr > LZ_MAX_CODE) {
|
|
return GIF_ERROR;
|
|
}
|
|
|
|
if (StackPtr != 0) {
|
|
/* Let pop the stack off before continueing to read the GIF
|
|
* file: */
|
|
while (StackPtr != 0 && i < LineLen) {
|
|
Line[i++] = Stack[--StackPtr];
|
|
}
|
|
}
|
|
|
|
while (i < LineLen) { /* Decode LineLen items. */
|
|
if (DGifDecompressInput(GifFile, &CrntCode) == GIF_ERROR) {
|
|
return GIF_ERROR;
|
|
}
|
|
|
|
if (CrntCode == EOFCode) {
|
|
/* Note however that usually we will not be here as we
|
|
* will stop decoding as soon as we got all the pixel,
|
|
* or EOF code will not be read at all, and
|
|
* DGifGetLine/Pixel clean everything. */
|
|
GifFile->Error = D_GIF_ERR_EOF_TOO_SOON;
|
|
return GIF_ERROR;
|
|
} else if (CrntCode == ClearCode) {
|
|
/* We need to start over again: */
|
|
for (j = 0; j <= LZ_MAX_CODE; j++) {
|
|
Prefix[j] = NO_SUCH_CODE;
|
|
}
|
|
Private->RunningCode = Private->EOFCode + 1;
|
|
Private->RunningBits = Private->BitsPerPixel + 1;
|
|
Private->MaxCode1 = 1 << Private->RunningBits;
|
|
LastCode = Private->LastCode = NO_SUCH_CODE;
|
|
} else {
|
|
/* Its regular code - if in pixel range simply add it to
|
|
* output stream, otherwise trace to codes linked list
|
|
* until the prefix is in pixel range: */
|
|
if (CrntCode < ClearCode) {
|
|
/* This is simple - its pixel scalar, so add it
|
|
* to output: */
|
|
Line[i++] = CrntCode;
|
|
} else {
|
|
/* Its a code to needed to be traced: trace the
|
|
* linked list until the prefix is a pixel,
|
|
* while pushing the suffix pixels on our stack.
|
|
* If we done, pop the stack in reverse (thats
|
|
* what stack is good for!) order to output. */
|
|
if (Prefix[CrntCode] == NO_SUCH_CODE) {
|
|
CrntPrefix = LastCode;
|
|
|
|
/* Only allowed if CrntCode is exactly
|
|
* the running code: In that case
|
|
* CrntCode = XXXCode, CrntCode or the
|
|
* prefix code is last code and the
|
|
* suffix char is exactly the prefix of
|
|
* last code! */
|
|
if (CrntCode ==
|
|
Private->RunningCode - 2) {
|
|
Suffix[Private->RunningCode -
|
|
2] = Stack[StackPtr++] =
|
|
DGifGetPrefixChar(
|
|
Prefix, LastCode,
|
|
ClearCode);
|
|
} else {
|
|
Suffix[Private->RunningCode -
|
|
2] = Stack[StackPtr++] =
|
|
DGifGetPrefixChar(
|
|
Prefix, CrntCode,
|
|
ClearCode);
|
|
}
|
|
} else {
|
|
CrntPrefix = CrntCode;
|
|
}
|
|
|
|
/* Now (if image is O.K.) we should not get a
|
|
* NO_SUCH_CODE during the trace. As we might
|
|
* loop forever, in case of defective image, we
|
|
* use StackPtr as loop counter and stop before
|
|
* overflowing Stack[]. */
|
|
while (StackPtr < LZ_MAX_CODE &&
|
|
CrntPrefix > ClearCode &&
|
|
CrntPrefix <= LZ_MAX_CODE) {
|
|
Stack[StackPtr++] = Suffix[CrntPrefix];
|
|
CrntPrefix = Prefix[CrntPrefix];
|
|
}
|
|
if (StackPtr >= LZ_MAX_CODE ||
|
|
CrntPrefix > LZ_MAX_CODE) {
|
|
GifFile->Error = D_GIF_ERR_IMAGE_DEFECT;
|
|
return GIF_ERROR;
|
|
}
|
|
/* Push the last character on stack: */
|
|
Stack[StackPtr++] = CrntPrefix;
|
|
|
|
/* Now lets pop all the stack into output: */
|
|
while (StackPtr != 0 && i < LineLen) {
|
|
Line[i++] = Stack[--StackPtr];
|
|
}
|
|
}
|
|
if (LastCode != NO_SUCH_CODE &&
|
|
Private->RunningCode - 2 < (LZ_MAX_CODE + 1) &&
|
|
Prefix[Private->RunningCode - 2] == NO_SUCH_CODE) {
|
|
Prefix[Private->RunningCode - 2] = LastCode;
|
|
|
|
if (CrntCode == Private->RunningCode - 2) {
|
|
/* Only allowed if CrntCode is exactly
|
|
* the running code: In that case
|
|
* CrntCode = XXXCode, CrntCode or the
|
|
* prefix code is last code and the
|
|
* suffix char is exactly the prefix of
|
|
* last code! */
|
|
Suffix[Private->RunningCode - 2] =
|
|
DGifGetPrefixChar(Prefix, LastCode,
|
|
ClearCode);
|
|
} else {
|
|
Suffix[Private->RunningCode - 2] =
|
|
DGifGetPrefixChar(Prefix, CrntCode,
|
|
ClearCode);
|
|
}
|
|
}
|
|
LastCode = CrntCode;
|
|
}
|
|
}
|
|
|
|
Private->LastCode = LastCode;
|
|
Private->StackPtr = StackPtr;
|
|
|
|
return GIF_OK;
|
|
}
|
|
|
|
/******************************************************************************
|
|
Routine to trace the Prefixes linked list until we get a prefix which is
|
|
not code, but a pixel value (less than ClearCode). Returns that pixel value.
|
|
If image is defective, we might loop here forever, so we limit the loops to
|
|
the maximum possible if image O.k. - LZ_MAX_CODE times.
|
|
******************************************************************************/
|
|
static int DGifGetPrefixChar(const GifPrefixType *Prefix, int Code,
|
|
int ClearCode) {
|
|
int i = 0;
|
|
|
|
while (Code > ClearCode && i++ <= LZ_MAX_CODE) {
|
|
if (Code > LZ_MAX_CODE) {
|
|
return NO_SUCH_CODE;
|
|
}
|
|
Code = Prefix[Code];
|
|
}
|
|
return Code;
|
|
}
|
|
|
|
/******************************************************************************
|
|
Interface for accessing the LZ codes directly. Set Code to the real code
|
|
(12bits), or to -1 if EOF code is returned.
|
|
******************************************************************************/
|
|
int DGifGetLZCodes(GifFileType *GifFile, int *Code) {
|
|
GifByteType *CodeBlock;
|
|
GifFilePrivateType *Private = (GifFilePrivateType *)GifFile->Private;
|
|
|
|
if (!IS_READABLE(Private)) {
|
|
/* This file was NOT open for reading: */
|
|
GifFile->Error = D_GIF_ERR_NOT_READABLE;
|
|
return GIF_ERROR;
|
|
}
|
|
|
|
if (DGifDecompressInput(GifFile, Code) == GIF_ERROR) {
|
|
return GIF_ERROR;
|
|
}
|
|
|
|
if (*Code == Private->EOFCode) {
|
|
/* Skip rest of codes (hopefully only NULL terminating block):
|
|
*/
|
|
do {
|
|
if (DGifGetCodeNext(GifFile, &CodeBlock) == GIF_ERROR) {
|
|
return GIF_ERROR;
|
|
}
|
|
} while (CodeBlock != NULL);
|
|
|
|
*Code = -1;
|
|
} else if (*Code == Private->ClearCode) {
|
|
/* We need to start over again: */
|
|
Private->RunningCode = Private->EOFCode + 1;
|
|
Private->RunningBits = Private->BitsPerPixel + 1;
|
|
Private->MaxCode1 = 1 << Private->RunningBits;
|
|
}
|
|
|
|
return GIF_OK;
|
|
}
|
|
|
|
/******************************************************************************
|
|
The LZ decompression input routine:
|
|
This routine is responsable for the decompression of the bit stream from
|
|
8 bits (bytes) packets, into the real codes.
|
|
Returns GIF_OK if read successfully.
|
|
******************************************************************************/
|
|
static int DGifDecompressInput(GifFileType *GifFile, int *Code) {
|
|
static const unsigned short CodeMasks[] = {
|
|
0x0000, 0x0001, 0x0003, 0x0007, 0x000f, 0x001f, 0x003f,
|
|
0x007f, 0x00ff, 0x01ff, 0x03ff, 0x07ff, 0x0fff};
|
|
|
|
GifFilePrivateType *Private = (GifFilePrivateType *)GifFile->Private;
|
|
|
|
GifByteType NextByte;
|
|
|
|
/* The image can't contain more than LZ_BITS per code. */
|
|
if (Private->RunningBits > LZ_BITS) {
|
|
GifFile->Error = D_GIF_ERR_IMAGE_DEFECT;
|
|
return GIF_ERROR;
|
|
}
|
|
|
|
while (Private->CrntShiftState < Private->RunningBits) {
|
|
/* Needs to get more bytes from input stream for next code: */
|
|
if (DGifBufferedInput(GifFile, Private->Buf, &NextByte) ==
|
|
GIF_ERROR) {
|
|
return GIF_ERROR;
|
|
}
|
|
Private->CrntShiftDWord |= ((unsigned long)NextByte)
|
|
<< Private->CrntShiftState;
|
|
Private->CrntShiftState += 8;
|
|
}
|
|
*Code = Private->CrntShiftDWord & CodeMasks[Private->RunningBits];
|
|
|
|
Private->CrntShiftDWord >>= Private->RunningBits;
|
|
Private->CrntShiftState -= Private->RunningBits;
|
|
|
|
/* If code cannot fit into RunningBits bits, must raise its size. Note
|
|
* however that codes above 4095 are used for special signaling.
|
|
* If we're using LZ_BITS bits already and we're at the max code, just
|
|
* keep using the table as it is, don't increment Private->RunningCode.
|
|
*/
|
|
if (Private->RunningCode < LZ_MAX_CODE + 2 &&
|
|
++Private->RunningCode > Private->MaxCode1 &&
|
|
Private->RunningBits < LZ_BITS) {
|
|
Private->MaxCode1 <<= 1;
|
|
Private->RunningBits++;
|
|
}
|
|
return GIF_OK;
|
|
}
|
|
|
|
/******************************************************************************
|
|
This routines read one GIF data block at a time and buffers it internally
|
|
so that the decompression routine could access it.
|
|
The routine returns the next byte from its internal buffer (or read next
|
|
block in if buffer empty) and returns GIF_OK if succesful.
|
|
******************************************************************************/
|
|
static int DGifBufferedInput(GifFileType *GifFile, GifByteType *Buf,
|
|
GifByteType *NextByte) {
|
|
if (Buf[0] == 0) {
|
|
/* Needs to read the next buffer - this one is empty: */
|
|
/* coverity[check_return] */
|
|
if (InternalRead(GifFile, Buf, 1) != 1) {
|
|
GifFile->Error = D_GIF_ERR_READ_FAILED;
|
|
return GIF_ERROR;
|
|
}
|
|
/* There shouldn't be any empty data blocks here as the LZW spec
|
|
* says the LZW termination code should come first. Therefore
|
|
* we shouldn't be inside this routine at that point.
|
|
*/
|
|
if (Buf[0] == 0) {
|
|
GifFile->Error = D_GIF_ERR_IMAGE_DEFECT;
|
|
return GIF_ERROR;
|
|
}
|
|
if (InternalRead(GifFile, &Buf[1], Buf[0]) != Buf[0]) {
|
|
GifFile->Error = D_GIF_ERR_READ_FAILED;
|
|
return GIF_ERROR;
|
|
}
|
|
*NextByte = Buf[1];
|
|
Buf[1] = 2; /* We use now the second place as last char read! */
|
|
Buf[0]--;
|
|
} else {
|
|
*NextByte = Buf[Buf[1]++];
|
|
Buf[0]--;
|
|
}
|
|
|
|
return GIF_OK;
|
|
}
|
|
|
|
/******************************************************************************
|
|
This routine is called in case of error during parsing image. We need to
|
|
decrease image counter and reallocate memory for saved images. Not decreasing
|
|
ImageCount may lead to null pointer dereference, because the last element in
|
|
SavedImages may point to the spoilt image and null pointer buffers.
|
|
*******************************************************************************/
|
|
void DGifDecreaseImageCounter(GifFileType *GifFile) {
|
|
GifFile->ImageCount--;
|
|
if (GifFile->SavedImages[GifFile->ImageCount].RasterBits != NULL) {
|
|
free(GifFile->SavedImages[GifFile->ImageCount].RasterBits);
|
|
}
|
|
|
|
// Realloc array according to the new image counter.
|
|
SavedImage *correct_saved_images = (SavedImage *)reallocarray(
|
|
GifFile->SavedImages, GifFile->ImageCount, sizeof(SavedImage));
|
|
if (correct_saved_images != NULL) {
|
|
GifFile->SavedImages = correct_saved_images;
|
|
}
|
|
}
|
|
|
|
/******************************************************************************
|
|
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) {
|
|
size_t ImageSize;
|
|
GifRecordType RecordType;
|
|
SavedImage *sp;
|
|
GifByteType *ExtData;
|
|
int ExtFunction;
|
|
|
|
GifFile->ExtensionBlocks = NULL;
|
|
GifFile->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];
|
|
/* Allocate memory for the image */
|
|
if (sp->ImageDesc.Width <= 0 ||
|
|
sp->ImageDesc.Height <= 0 ||
|
|
sp->ImageDesc.Width >
|
|
(INT_MAX / sp->ImageDesc.Height)) {
|
|
DGifDecreaseImageCounter(GifFile);
|
|
return GIF_ERROR;
|
|
}
|
|
ImageSize = sp->ImageDesc.Width * sp->ImageDesc.Height;
|
|
|
|
if (ImageSize > (SIZE_MAX / sizeof(GifPixelType))) {
|
|
DGifDecreaseImageCounter(GifFile);
|
|
return GIF_ERROR;
|
|
}
|
|
sp->RasterBits = (unsigned char *)reallocarray(
|
|
NULL, ImageSize, sizeof(GifPixelType));
|
|
|
|
if (sp->RasterBits == NULL) {
|
|
DGifDecreaseImageCounter(GifFile);
|
|
return GIF_ERROR;
|
|
}
|
|
|
|
if (sp->ImageDesc.Interlace) {
|
|
int i, j;
|
|
/*
|
|
* The way an interlaced image should be read -
|
|
* offsets and jumps...
|
|
*/
|
|
static const int InterlacedOffset[] = {0, 4, 2,
|
|
1};
|
|
static const int InterlacedJumps[] = {8, 8, 4,
|
|
2};
|
|
/* Need to perform 4 passes on the image */
|
|
for (i = 0; i < 4; i++) {
|
|
for (j = InterlacedOffset[i];
|
|
j < sp->ImageDesc.Height;
|
|
j += InterlacedJumps[i]) {
|
|
if (DGifGetLine(
|
|
GifFile,
|
|
sp->RasterBits +
|
|
j * sp->ImageDesc
|
|
.Width,
|
|
sp->ImageDesc.Width) ==
|
|
GIF_ERROR) {
|
|
DGifDecreaseImageCounter(
|
|
GifFile);
|
|
return GIF_ERROR;
|
|
}
|
|
}
|
|
}
|
|
} else {
|
|
if (DGifGetLine(GifFile, sp->RasterBits,
|
|
ImageSize) == GIF_ERROR) {
|
|
DGifDecreaseImageCounter(GifFile);
|
|
return GIF_ERROR;
|
|
}
|
|
}
|
|
|
|
if (GifFile->ExtensionBlocks) {
|
|
sp->ExtensionBlocks = GifFile->ExtensionBlocks;
|
|
sp->ExtensionBlockCount =
|
|
GifFile->ExtensionBlockCount;
|
|
|
|
GifFile->ExtensionBlocks = NULL;
|
|
GifFile->ExtensionBlockCount = 0;
|
|
}
|
|
break;
|
|
|
|
case EXTENSION_RECORD_TYPE:
|
|
if (DGifGetExtension(GifFile, &ExtFunction, &ExtData) ==
|
|
GIF_ERROR) {
|
|
return (GIF_ERROR);
|
|
}
|
|
/* Create an extension block with our data */
|
|
if (ExtData != NULL) {
|
|
if (GifAddExtensionBlock(
|
|
&GifFile->ExtensionBlockCount,
|
|
&GifFile->ExtensionBlocks, ExtFunction,
|
|
ExtData[0], &ExtData[1]) == GIF_ERROR) {
|
|
return (GIF_ERROR);
|
|
}
|
|
}
|
|
for (;;) {
|
|
if (DGifGetExtensionNext(GifFile, &ExtData) ==
|
|
GIF_ERROR) {
|
|
return (GIF_ERROR);
|
|
}
|
|
if (ExtData == NULL) {
|
|
break;
|
|
}
|
|
/* Continue the extension block */
|
|
if (GifAddExtensionBlock(
|
|
&GifFile->ExtensionBlockCount,
|
|
&GifFile->ExtensionBlocks,
|
|
CONTINUE_EXT_FUNC_CODE, ExtData[0],
|
|
&ExtData[1]) == GIF_ERROR) {
|
|
return (GIF_ERROR);
|
|
}
|
|
}
|
|
break;
|
|
|
|
case TERMINATE_RECORD_TYPE:
|
|
break;
|
|
|
|
default: /* Should be trapped by DGifGetRecordType */
|
|
break;
|
|
}
|
|
} while (RecordType != TERMINATE_RECORD_TYPE);
|
|
|
|
/* Sanity check for corrupted file */
|
|
if (GifFile->ImageCount == 0) {
|
|
GifFile->Error = D_GIF_ERR_NO_IMAG_DSCR;
|
|
return (GIF_ERROR);
|
|
}
|
|
|
|
return (GIF_OK);
|
|
}
|
|
|
|
/* end */
|