static int
ChnMatch(
Tcl_Channel chan, /* The image channel, open for reading. */
const char *fileName, /* The name of the image file. */
Tcl_Obj *format, /* User-specified format object, or NULL. */
int *widthPtr, /* The dimensions of the image are */
int *heightPtr, /* returned here if the file is a valid
* raw GIF file. */
Tcl_Interp *interp /* interpreter */
) {
GIFImageConfig gifConf;
memset(&gifConf, 0, sizeof(GIFImageConfig));
gifConf.handle.data = (char *) chan;
gifConf.handle.state = IMG_CHAN;
return ReadGIFHeader(&gifConf, widthPtr, heightPtr);
}
GIFLoad::GIFLoad(BPositionIO* input, BPositionIO* output)
:
fatalerror(false),
fInput(input),
fOutput(output),
fPalette(NULL),
fHeadMemblock(NULL),
fScanLine(NULL)
{
fInput->Seek(0, SEEK_SET);
if (!ReadGIFHeader()) {
fatalerror = true;
return;
}
if (debug) {
syslog(LOG_INFO, "GIFLoad::GIFLoad() - Image dimensions are %d x %d\n",
fWidth, fHeight);
}
unsigned char c;
if (fInput->Read(&c, 1) < 1) {
fatalerror = true;
return;
}
while (c != TERMINATOR_INTRODUCER) {
if (c == DESCRIPTOR_INTRODUCER) {
if ((!ReadGIFImageHeader()) || (!ReadGIFImageData())) {
if (debug) {
syslog(LOG_ERR, "GIFLoad::GIFLoad() - "
"A fatal error occurred\n");
}
fatalerror = true;
} else {
if (debug) {
syslog(LOG_INFO, "GIFLoad::GIFLoad() - "
"Found a single image and leaving\n");
}
}
free(fScanLine);
fScanLine = NULL;
return;
} else if (c == EXTENSION_INTRODUCER) {
unsigned char d;
if (fInput->Read(&d, 1) < 1) {
fatalerror = true;
return;
}
if (d == LOOP_BLOCK_LABEL) {
if (!ReadGIFLoopBlock()) {
fatalerror = true;
return;
}
} else if (d == GRAPHIC_CONTROL_LABEL) {
if (!ReadGIFControlBlock()) {
fatalerror = true;
return;
}
} else if (d == COMMENT_EXTENSION_LABEL) {
if (!ReadGIFCommentBlock()) {
fatalerror = true;
return;
}
} else {
if (!ReadGIFUnknownBlock(d)) {
fatalerror = true;
return;
}
}
} else if (c != BLOCK_TERMINATOR) {
if (!ReadGIFUnknownBlock(c)) {
fatalerror = true;
return;
}
}
if (fInput->Read(&c, 1) < 1) {
fatalerror = true;
return;
}
}
if (debug)
syslog(LOG_INFO, "GIFLoad::GIFLoad() - Done\n");
}
GIFLoad::GIFLoad(BPositionIO *input, BPositionIO *output)
:
fatalerror(false),
fInput(input),
fOutput(output),
fPalette(NULL),
fHeadMemblock(NULL),
fScanLine(NULL)
{
fInput->Seek(0, SEEK_SET);
if (!ReadGIFHeader()) {
fatalerror = true;
return;
}
if (debug)
syslog(LOG_ERR, "GIFLoad::GIFLoad() - Image dimensions are %d x %d\n",
fWidth, fHeight);
unsigned char c;
if (fInput->Read(&c, 1) < 1) {
fatalerror = true;
return;
}
while (c != 0x3b) {
if (c == 0x2c) {
if ((!ReadGIFImageHeader()) || (!ReadGIFImageData())) {
if (debug)
syslog(LOG_ERR, "GIFLoad::GIFLoad() - A fatal error occurred\n");
fatalerror = true;
} else {
if (debug)
syslog(LOG_ERR, "GIFLoad::GIFLoad() - Found a single image and "
"leaving\n");
}
free(fScanLine);
fScanLine = NULL;
return;
} else if (c == 0x21) {
unsigned char d;
if (fInput->Read(&d, 1) < 1) {
fatalerror = true;
return;
}
if (d == 0xff) {
if (!ReadGIFLoopBlock()) {
fatalerror = true;
return;
}
} else if (d == 0xf9) {
if (!ReadGIFControlBlock()) {
fatalerror = true;
return;
}
} else if (d == 0xfe) {
if (!ReadGIFCommentBlock()) {
fatalerror = true;
return;
}
} else {
if (!ReadGIFUnknownBlock(d)) {
fatalerror = true;
return;
}
}
} else if (c != 0x00) {
if (!ReadGIFUnknownBlock(c)) {
fatalerror = true;
return;
}
}
if (fInput->Read(&c, 1) < 1) {
fatalerror = true;
return;
}
}
if (debug)
syslog(LOG_ERR, "GIFLoad::GIFLoad() - Done\n");
}