diff options
Diffstat (limited to 'generic/tkImgGIF.c')
| -rw-r--r-- | generic/tkImgGIF.c | 1380 |
1 files changed, 723 insertions, 657 deletions
diff --git a/generic/tkImgGIF.c b/generic/tkImgGIF.c index 6fe8627..9d11631 100644 --- a/generic/tkImgGIF.c +++ b/generic/tkImgGIF.c @@ -1,17 +1,17 @@ /* * tkImgGIF.c -- * - * A photo image file handler for GIF files. Reads 87a and 89a GIF - * files. At present, there only is a file write function. GIF images - * may be read using the -data option of the photo image. The data may be - * given as a binary string in a Tcl_Obj or by representing - * the data as BASE64 encoded ascii. Derived from the giftoppm code - * found in the pbmplus package and tkImgFmtPPM.c in the tk4.0b2 - * distribution. + * A photo image file handler for GIF files. Reads 87a and 89a GIF files. + * At present, there only is a file write function. GIF images may be + * read using the -data option of the photo image. The data may be given + * as a binary string in a Tcl_Obj or by representing the data as BASE64 + * encoded ascii. Derived from the giftoppm code found in the pbmplus + * package and tkImgFmtPPM.c in the tk4.0b2 distribution. * * Copyright (c) Reed Wade (wade@cs.utk.edu), University of Tennessee * Copyright (c) 1995-1997 Sun Microsystems, Inc. * Copyright (c) 1997 Australian National University + * Copyright (c) 2005 Donal K. Fellows * * See the file "license.terms" for information on usage and redistribution * of this file, and for a DISCLAIMER OF ALL WARRANTIES. @@ -27,18 +27,20 @@ * | copies and that both that copyright notice and this permission | * | notice appear in supporting documentation. This software is | * | provided "as is" without express or implied warranty. | - * +-------------------------------------------------------------------+ + * +--------------------------------------------------------------------+ + * + * This file also contains code from miGIF. See lower down in file for the + * applicable copyright notice for that portion. * - * RCS: @(#) $Id: tkImgGIF.c,v 1.26 2004/07/27 21:19:32 das Exp $ + * RCS: @(#) $Id: tkImgGIF.c,v 1.27 2005/06/19 21:49:08 dkf Exp $ */ /* - * GIF's are represented as data in base64 format. - * base64 strings consist of 4 6-bit characters -> 3 8 bit bytes. - * A-Z, a-z, 0-9, + and / represent the 64 values (in order). - * '=' is a trailing padding char when the un-encoded data is not a - * multiple of 3 bytes. We'll ignore white space when encountered. - * Any other invalid character is treated as an EOF + * GIF's are represented as data in either binary or base64 format. base64 + * strings consist of 4 6-bit characters -> 3 8 bit bytes. A-Z, a-z, 0-9, + + * and / represent the 64 values (in order). '=' is a trailing padding char + * when the un-encoded data is not a multiple of 3 bytes. We'll ignore white + * space when encountered. Any other invalid character is treated as an EOF */ #define GIF_SPECIAL (256) @@ -48,15 +50,15 @@ #define GIF_DONE (GIF_SPECIAL+4) /* - * structure to "mimic" FILE for Mread, so we can look like fread. - * The decoder state keeps track of which byte we are about to read, - * or EOF. + * structure to "mimic" FILE for Mread, so we can look like fread. The + * decoder state keeps track of which byte we are about to read, or EOF. */ typedef struct mFile { unsigned char *data; /* mmencoded source string */ int c; /* bits left over from previous character */ int state; /* decoder state (0-4 or GIF_DONE) */ + int length; /* Total amount of bytes in data */ } MFile; #include "tkInt.h" @@ -64,12 +66,12 @@ typedef struct mFile { /* * Non-ASCII encoding support: - * Most data in a GIF image is binary and is treated as such. However, - * a few key bits are stashed in ASCII. If we try to compare those pieces - * to the char they represent, it will fail on any non-ASCII (eg, EBCDIC) - * system. To accomodate these systems, we test against the numeric value - * of the ASCII characters instead of the characters themselves. This is - * encoding independant. + * Most data in a GIF image is binary and is treated as such. However, a few + * key bits are stashed in ASCII. If we try to compare those pieces to the + * char they represent, it will fail on any non-ASCII (eg, EBCDIC) system. To + * accomodate these systems, we test against the numeric value of the ASCII + * characters instead of the characters themselves. This is encoding + * independant. */ static CONST char GIF87a[] = { /* ASCII GIF87a */ @@ -78,21 +80,31 @@ static CONST char GIF87a[] = { /* ASCII GIF87a */ static CONST char GIF89a[] = { /* ASCII GIF89a */ 0x47, 0x49, 0x46, 0x38, 0x39, 0x61, 0x00 }; -# define GIF_TERMINATOR 0x3b /* ASCII ; */ -# define GIF_EXTENSION 0x21 /* ASCII ! */ -# define GIF_START 0x2c /* ASCII , */ +#define GIF_TERMINATOR 0x3b /* ASCII ; */ +#define GIF_EXTENSION 0x21 /* ASCII ! */ +#define GIF_START 0x2c /* ASCII , */ + +#define INLINE_DATA_BINARY ((const char *) 0x01) +#define INLINE_DATA_BASE64 ((const char *) 0x02) /* - * HACK ALERT!! HACK ALERT!! HACK ALERT!! - * This code is hard-wired for reading from files. In order to read - * from a data stream, we'll trick fread so we can reuse the same code. - * 0==from file; 1==from base64 encoded data; 2==from binary data + * HACK ALERT!! HACK ALERT!! HACK ALERT!! + * This code is hard-wired for reading from files. In order to read from a + * data stream, we'll trick fread so we can reuse the same code. 0==from file; + * 1==from base64 encoded data; 2==from binary data */ -typedef struct ThreadSpecificData { - int fromData; -} ThreadSpecificData; -static Tcl_ThreadDataKey dataKey; +typedef struct { + const char *fromData; + unsigned char workingBuffer[280]; + struct { + int bytes; + int done; + unsigned int window; + int bitsInWindow; + unsigned char *c; + } reader; +} GIFImageConfig; /* * The format record for the GIF file format: @@ -101,18 +113,17 @@ static Tcl_ThreadDataKey dataKey; static int FileMatchGIF _ANSI_ARGS_((Tcl_Channel chan, CONST char *fileName, Tcl_Obj *format, int *widthPtr, int *heightPtr, Tcl_Interp *interp)); -static int FileReadGIF _ANSI_ARGS_((Tcl_Interp *interp, - Tcl_Channel chan, CONST char *fileName, Tcl_Obj *format, +static int FileReadGIF _ANSI_ARGS_((Tcl_Interp *interp, Tcl_Channel chan, + CONST char *fileName, Tcl_Obj *format, Tk_PhotoHandle imageHandle, int destX, int destY, int width, int height, int srcX, int srcY)); -static int StringMatchGIF _ANSI_ARGS_(( Tcl_Obj *dataObj, - Tcl_Obj *format, int *widthPtr, int *heightPtr, - Tcl_Interp *interp)); +static int StringMatchGIF _ANSI_ARGS_(( Tcl_Obj *dataObj, Tcl_Obj *format, + int *widthPtr, int *heightPtr, Tcl_Interp *interp)); static int StringReadGIF _ANSI_ARGS_((Tcl_Interp *interp, Tcl_Obj *dataObj, Tcl_Obj *format, Tk_PhotoHandle imageHandle, int destX, int destY, int width, int height, int srcX, int srcY)); -static int FileWriteGIF _ANSI_ARGS_((Tcl_Interp *interp, +static int FileWriteGIF _ANSI_ARGS_((Tcl_Interp *interp, CONST char *filename, Tcl_Obj *format, Tk_PhotoImageBlock *blockPtr)); static int CommonWriteGIF _ANSI_ARGS_((Tcl_Interp *interp, @@ -139,54 +150,54 @@ Tk_PhotoImageFormat tkImgFmtGIF = { #define CM_ALPHA 3 #define MAX_LWZ_BITS 12 #define LM_to_uint(a,b) (((b)<<8)|(a)) -#define ReadOK(file,buffer,len) (Fread(buffer, len, 1, file) != 0) /* * Prototypes for local procedures defined in this file: */ -static int DoExtension _ANSI_ARGS_((Tcl_Channel chan, int label, - int *transparent)); -static int GetCode _ANSI_ARGS_((Tcl_Channel chan, int code_size, - int flag)); -static int GetDataBlock _ANSI_ARGS_((Tcl_Channel chan, - unsigned char *buf)); -static int ReadColorMap _ANSI_ARGS_((Tcl_Channel chan, int number, - unsigned char buffer[MAXCOLORMAPSIZE][4])); -static int ReadGIFHeader _ANSI_ARGS_((Tcl_Channel chan, - int *widthPtr, int *heightPtr)); -static int ReadImage _ANSI_ARGS_((Tcl_Interp *interp, - char *imagePtr, Tcl_Channel chan, - int len, int rows, - unsigned char cmap[MAXCOLORMAPSIZE][4], - int width, int height, int srcX, int srcY, - int interlace, int transparent)); +static int DoExtension _ANSI_ARGS_((GIFImageConfig *gifConfPtr, + Tcl_Channel chan, int label, unsigned char *buffer, + int *transparent)); +static int GetCode _ANSI_ARGS_((Tcl_Channel chan, int code_size, int flag, + GIFImageConfig *gifConfPtr)); +static int GetDataBlock _ANSI_ARGS_((GIFImageConfig *gifConfPtr, + Tcl_Channel chan, unsigned char *buf)); +static int ReadColorMap _ANSI_ARGS_((GIFImageConfig *gifConfPtr, + Tcl_Channel chan, int number, + unsigned char buffer[MAXCOLORMAPSIZE][4])); +static int ReadGIFHeader _ANSI_ARGS_((GIFImageConfig *gifConfPtr, + Tcl_Channel chan, int *widthPtr, int *heightPtr)); +static int ReadImage _ANSI_ARGS_((GIFImageConfig *gifConfPtr, + Tcl_Interp *interp, char *imagePtr, Tcl_Channel chan, + int len, int rows, unsigned char cmap[MAXCOLORMAPSIZE][4], + int width, int height, int srcX, int srcY, int interlace, + int transparent)); /* * these are for the BASE64 image reader code only */ -static int Fread _ANSI_ARGS_((unsigned char *dst, size_t size, - size_t count, Tcl_Channel chan)); -static int Mread _ANSI_ARGS_((unsigned char *dst, size_t size, - size_t count, MFile *handle)); -static int Mgetc _ANSI_ARGS_((MFile *handle)); -static int char64 _ANSI_ARGS_((int c)); -static void mInit _ANSI_ARGS_((unsigned char *string, - MFile *handle)); - +static int Fread _ANSI_ARGS_((GIFImageConfig *gifConfPtr, + unsigned char *dst, size_t size, size_t count, + Tcl_Channel chan)); +static int Mread _ANSI_ARGS_((unsigned char *dst, size_t size, + size_t count, MFile *handle)); +static int Mgetc _ANSI_ARGS_((MFile *handle)); +static int char64 _ANSI_ARGS_((int c)); +static void mInit _ANSI_ARGS_((unsigned char *string, MFile *handle, + int length)); /* *---------------------------------------------------------------------- * * FileMatchGIF -- * - * This procedure is invoked by the photo image type to see if - * a file contains image data in GIF format. + * This procedure is invoked by the photo image type to see if a file + * contains image data in GIF format. * * Results: - * The return value is 1 if the first characters in file f look - * like GIF data, and 0 otherwise. + * The return value is 1 if the first characters in file f look like GIF + * data, and 0 otherwise. * * Side effects: * The access position in f may change. @@ -199,12 +210,14 @@ FileMatchGIF(chan, fileName, format, widthPtr, heightPtr, interp) Tcl_Channel chan; /* The image file, open for reading. */ CONST char *fileName; /* The name of the image file. */ Tcl_Obj *format; /* User-specified format object, or NULL. */ - int *widthPtr, *heightPtr; /* The dimensions of the image are - * returned here if the file is a valid - * raw GIF file. */ + int *widthPtr, *heightPtr; /* The dimensions of the image are returned + * here if the file is a valid raw GIF file. */ Tcl_Interp *interp; /* not used */ { - return ReadGIFHeader(chan, widthPtr, heightPtr); + GIFImageConfig gifConf; + + memset(&gifConf, 0, sizeof(GIFImageConfig)); + return ReadGIFHeader(&gifConf, chan, widthPtr, heightPtr); } /* @@ -212,17 +225,16 @@ FileMatchGIF(chan, fileName, format, widthPtr, heightPtr, interp) * * FileReadGIF -- * - * This procedure is called by the photo image type to read - * GIF format data from a file and write it into a given - * photo image. + * This procedure is called by the photo image type to read GIF format + * data from a file and write it into a given photo image. * * Results: - * A standard TCL completion code. If TCL_ERROR is returned - * then an error message is left in the interp's result. + * A standard TCL completion code. If TCL_ERROR is returned then an + * error message is left in the interp's result. * * Side effects: - * The access position in file f is changed, and new data is - * added to the image given by imageHandle. + * The access position in file f is changed, and new data is added to the + * image given by imageHandle. * *---------------------------------------------------------------------- */ @@ -235,12 +247,12 @@ FileReadGIF(interp, chan, fileName, format, imageHandle, destX, destY, CONST char *fileName; /* The name of the image file. */ Tcl_Obj *format; /* User-specified format object, or NULL. */ Tk_PhotoHandle imageHandle; /* The photo image to write into. */ - int destX, destY; /* Coordinates of top-left pixel in - * photo image to be written to. */ - int width, height; /* Dimensions of block of photo image to - * be written to. */ - int srcX, srcY; /* Coordinates of top-left pixel to be used - * in image being read. */ + int destX, destY; /* Coordinates of top-left pixel in photo + * image to be written to. */ + int width, height; /* Dimensions of block of photo image to be + * written to. */ + int srcX, srcY; /* Coordinates of top-left pixel to be used in + * image being read. */ { int fileWidth, fileHeight; int nBytes, index = 0, argc = 0, i; @@ -254,27 +266,38 @@ FileReadGIF(interp, chan, fileName, format, imageHandle, destX, destY, static CONST char *optionStrings[] = { "-index", NULL }; + GIFImageConfig gifConf, *gifConfPtr = &gifConf; + + /* + * Decode the magic used to convey when we're sourcing data from a string + * source and not a file. + */ + + memset(gifConfPtr, 0, sizeof(GIFImageConfig)); + if (fileName == INLINE_DATA_BINARY || fileName == INLINE_DATA_BASE64) { + gifConfPtr->fromData = fileName; + fileName = "inline data"; + } if (format && Tcl_ListObjGetElements(interp, format, &argc, &objv) != TCL_OK) { return TCL_ERROR; } for (i = 1; i < argc; i++) { - if (Tcl_GetIndexFromObj(interp, objv[i], optionStrings, "option name", 0, - &nBytes) != TCL_OK) { + if (Tcl_GetIndexFromObj(interp, objv[i], optionStrings, "option name", + 0, &nBytes) != TCL_OK) { return TCL_ERROR; } if (i == (argc-1)) { Tcl_AppendResult(interp, "no value given for \"", - Tcl_GetStringFromObj(objv[i], NULL), - "\" option", (char *) NULL); + Tcl_GetString(objv[i]), "\" option", (char *) NULL); return TCL_ERROR; } if (Tcl_GetIntFromObj(interp, objv[++i], &index) != TCL_OK) { return TCL_ERROR; } } - if (!ReadGIFHeader(chan, &fileWidth, &fileHeight)) { + if (!ReadGIFHeader(gifConfPtr, chan, &fileWidth, &fileHeight)) { Tcl_AppendResult(interp, "couldn't read GIF header from file \"", fileName, "\"", NULL); return TCL_ERROR; @@ -285,13 +308,13 @@ FileReadGIF(interp, chan, fileName, format, imageHandle, destX, destY, return TCL_ERROR; } - if (Fread(buf, 1, 3, chan) != 3) { + if (Fread(gifConfPtr, buf, 1, 3, chan) != 3) { return TCL_OK; } bitPixel = 2<<(buf[0]&0x07); if (BitSet(buf[0], LOCALCOLORMAP)) { /* Global Colormap */ - if (!ReadColorMap(chan, bitPixel, colorMap)) { + if (!ReadColorMap(gifConfPtr, chan, bitPixel, colorMap)) { Tcl_AppendResult(interp, "error reading color map", (char *) NULL); return TCL_ERROR; @@ -325,13 +348,14 @@ FileReadGIF(interp, chan, fileName, format, imageHandle, destX, destY, block.pixelPtr = NULL; while (1) { - if (Fread(buf, 1, 1, chan) != 1) { + if (Fread(gifConfPtr, buf, 1, 1, chan) != 1) { /* * Premature end of image. */ - Tcl_AppendResult(interp,"premature end of image data for this index", - (char *) NULL); + Tcl_AppendResult(interp, + "premature end of image data for this index", + (char *) NULL); goto error; } @@ -340,7 +364,7 @@ FileReadGIF(interp, chan, fileName, format, imageHandle, destX, destY, * GIF terminator. */ - Tcl_AppendResult(interp,"no image data for this index", + Tcl_AppendResult(interp, "no image data for this index", (char *) NULL); goto error; } @@ -350,13 +374,14 @@ FileReadGIF(interp, chan, fileName, format, imageHandle, destX, destY, * This is a GIF extension. */ - if (Fread(buf, 1, 1, chan) != 1) { + if (Fread(gifConfPtr, buf, 1, 1, chan) != 1) { Tcl_SetResult(interp, "error reading extension function code in GIF image", TCL_STATIC); goto error; } - if (DoExtension(chan, buf[0], &transparent) < 0) { + if (DoExtension(gifConfPtr, chan, buf[0], + gifConfPtr->workingBuffer, &transparent) < 0) { Tcl_SetResult(interp, "error reading extension in GIF image", TCL_STATIC); goto error; @@ -371,15 +396,15 @@ FileReadGIF(interp, chan, fileName, format, imageHandle, destX, destY, continue; } - if (Fread(buf, 1, 9, chan) != 9) { + if (Fread(gifConfPtr, buf, 1, 9, chan) != 9) { Tcl_SetResult(interp, "couldn't read left/top/width/height in GIF image", TCL_STATIC); goto error; } - fileWidth = LM_to_uint(buf[4],buf[5]); - fileHeight = LM_to_uint(buf[6],buf[7]); + fileWidth = LM_to_uint(buf[4], buf[5]); + fileHeight = LM_to_uint(buf[6], buf[7]); bitPixel = 1<<((buf[8]&0x07)+1); @@ -388,7 +413,7 @@ FileReadGIF(interp, chan, fileName, format, imageHandle, destX, destY, * This is not the image we want to read: skip it. */ if (BitSet(buf[8], LOCALCOLORMAP)) { - if (!ReadColorMap(chan, bitPixel, colorMap)) { + if (!ReadColorMap(gifConfPtr, chan, bitPixel, colorMap)) { Tcl_AppendResult(interp, "error reading color map", (char *) NULL); goto error; @@ -400,43 +425,43 @@ FileReadGIF(interp, chan, fileName, format, imageHandle, destX, destY, */ if (trashBuffer == NULL) { nBytes = fileWidth * fileHeight * 3; - trashBuffer = - (unsigned char *) ckalloc((unsigned int) nBytes); + trashBuffer = (unsigned char *) ckalloc((unsigned int) nBytes); } /* - * Slurp! Process the data for this image and stuff it in - * a trash buffer. + * Slurp! Process the data for this image and stuff it in a trash + * buffer. * - * Yes, it might be more efficient here to *not* store the - * data (we're just going to throw it away later). - * However, I elected to implement it this way for good - * reasons. First, I wanted to avoid duplicating the - * (fairly complex) LWZ decoder in ReadImage. Fine, you - * say, why didn't you just modify it to allow the use of - * a NULL specifier for the output buffer? I tried that, - * but it negatively impacted the performance of what I - * think will be the common case: reading the first image - * in the file. Rather than marginally improve the speed - * of the less frequent case, I chose to maintain high - * performance for the common case. + * Yes, it might be more efficient here to *not* store the data + * (we're just going to throw it away later). However, I elected + * to implement it this way for good reasons. First, I wanted to + * avoid duplicating the (fairly complex) LWZ decoder in + * ReadImage. Fine, you say, why didn't you just modify it to + * allow the use of a NULL specifier for the output buffer? I + * tried that, but it negatively impacted the performance of what + * I think will be the common case: reading the first image in the + * file. Rather than marginally improve the speed of the less + * frequent case, I chose to maintain high performance for the + * common case. */ - if (ReadImage(interp, (char *) trashBuffer, chan, fileWidth, - fileHeight, colorMap, 0, 0, 0, 0, 0, -1) != TCL_OK) { + + if (ReadImage(gifConfPtr, interp, (char *)trashBuffer, chan, + fileWidth, fileHeight, colorMap, 0, 0, 0, 0, 0, + -1) != TCL_OK) { goto error; } continue; } if (BitSet(buf[8], LOCALCOLORMAP)) { - if (!ReadColorMap(chan, bitPixel, colorMap)) { + if (!ReadColorMap(gifConfPtr, chan, bitPixel, colorMap)) { Tcl_AppendResult(interp, "error reading color map", (char *) NULL); goto error; } } - index = LM_to_uint(buf[0],buf[1]); + index = LM_to_uint(buf[0], buf[1]); srcX -= index; if (srcX<0) { destX -= srcX; width += srcX; @@ -447,7 +472,7 @@ FileReadGIF(interp, chan, fileName, format, imageHandle, destX, destY, width = fileWidth; } - index = LM_to_uint(buf[2],buf[3]); + index = LM_to_uint(buf[2], buf[3]); srcY -= index; if (index > srcY) { destY -= srcY; height += srcY; @@ -470,9 +495,9 @@ FileReadGIF(interp, chan, fileName, format, imageHandle, destX, destY, nBytes = block.pitch * fileHeight; block.pixelPtr = (unsigned char *) ckalloc((unsigned) nBytes); - if (ReadImage(interp, (char *) block.pixelPtr, chan, fileWidth, - fileHeight, colorMap, fileWidth, fileHeight, srcX, srcY, - BitSet(buf[8], INTERLACE), transparent) != TCL_OK) { + if (ReadImage(gifConfPtr, interp, (char *) block.pixelPtr, chan, + fileWidth, fileHeight, colorMap, fileWidth, fileHeight, srcX, + srcY, BitSet(buf[8], INTERLACE), transparent) != TCL_OK) { goto error; } break; @@ -483,7 +508,7 @@ FileReadGIF(interp, chan, fileName, format, imageHandle, destX, destY, goto error; } - noerror: + noerror: /* * If a trash buffer has been allocated, free it now. */ @@ -496,7 +521,7 @@ FileReadGIF(interp, chan, fileName, format, imageHandle, destX, destY, Tcl_AppendResult(interp, tkImgFmtGIF.name, (char *) NULL); return TCL_OK; - error: + error: /* * If a trash buffer has been allocated, free it now. */ @@ -514,15 +539,15 @@ FileReadGIF(interp, chan, fileName, format, imageHandle, destX, destY, * * StringMatchGIF -- * - * This procedure is invoked by the photo image type to see if - * an object contains image data in GIF format. + * This procedure is invoked by the photo image type to see if an object + * contains image data in GIF format. * * Results: - * The return value is 1 if the first characters in the data are - * like GIF data, and 0 otherwise. + * The return value is 1 if the first characters in the data are like GIF + * data, and 0 otherwise. * * Side effects: - * the size of the image is placed in widthPre and heightPtr. + * The size of the image is placed in widthPtr and heightPtr. * *---------------------------------------------------------------------- */ @@ -557,7 +582,7 @@ StringMatchGIF(dataObj, format, widthPtr, heightPtr, interp) /* * Try interpreting the data as Base64 encoded */ - mInit((unsigned char *) data, &handle); + mInit((unsigned char *) data, &handle, length); got = Mread(header, 10, 1, &handle); if (got != 10 || ((strncmp(GIF87a, (char *) header, 6) != 0) @@ -567,28 +592,27 @@ StringMatchGIF(dataObj, format, widthPtr, heightPtr, interp) } else { memcpy((VOID *) header, (VOID *) data, 10); } - *widthPtr = LM_to_uint(header[6],header[7]); - *heightPtr = LM_to_uint(header[8],header[9]); + *widthPtr = LM_to_uint(header[6], header[7]); + *heightPtr = LM_to_uint(header[8], header[9]); return 1; } /* *---------------------------------------------------------------------- * - * StringReadGif -- -- + * StringReadGIF -- * - * This procedure is called by the photo image type to read - * GIF format data from an object, optionally base64 encoded, - * and give it to the photo image. + * This procedure is called by the photo image type to read GIF format + * data from an object, optionally base64 encoded, and give it to the + * photo image. * * Results: - * A standard TCL completion code. If TCL_ERROR is returned - * then an error message is left in the interp's result. + * A standard TCL completion code. If TCL_ERROR is returned then an + * error message is left in the interp's result. * * Side effects: - * new data is added to the image given by imageHandle. This - * procedure calls FileReadGif by redefining the operation of - * fprintf temporarily. + * New data is added to the image given by imageHandle. This procedure + * calls FileReadGIF by redefining the operation of fprintf temporarily. * *---------------------------------------------------------------------- */ @@ -600,49 +624,44 @@ StringReadGIF(interp, dataObj, format, imageHandle, Tcl_Obj *dataObj; /* object containing the image */ Tcl_Obj *format; /* format object, or NULL */ Tk_PhotoHandle imageHandle; /* the image to write this data into */ - int destX, destY; /* The rectangular region of the */ - int width, height; /* image to copy */ + int destX, destY; /* The rectangular region of the */ + int width, height; /* image to copy */ int srcX, srcY; { - int result; MFile handle; - ThreadSpecificData *tsdPtr = (ThreadSpecificData *) - Tcl_GetThreadData(&dataKey, sizeof(ThreadSpecificData)); - Tcl_Channel dataSrc; - char *data; + int length; + char *data = (char *) Tcl_GetByteArrayFromObj(dataObj, &length); - /* - * Check whether the data is Base64 encoded - */ - data = (char *) Tcl_GetByteArrayFromObj(dataObj, NULL); - if ((strncmp(GIF87a, data, 6) != 0) && (strncmp(GIF89a, data, 6) != 0)) { - mInit((unsigned char *)data, &handle); - tsdPtr->fromData = 1; - dataSrc = (Tcl_Channel) &handle; + mInit((unsigned char *)data, &handle, length); + + if (strncmp(GIF87a, data, 6) && strncmp(GIF89a, data, 6)) { + /* + * Check whether the data is Base64 encoded by doing a + * character-by-charcter comparison with the binary-format headers; + * BASE64-encoded never matches (matching the other way is harder + * because of potential padding). + */ + + return FileReadGIF(interp, (Tcl_Channel) &handle, INLINE_DATA_BASE64, + format, imageHandle, destX, destY, width, height, srcX, srcY); } else { - tsdPtr->fromData = 2; - mInit((unsigned char *)data, &handle); - dataSrc = (Tcl_Channel) &handle; + return FileReadGIF(interp, (Tcl_Channel) &handle, INLINE_DATA_BINARY, + format, imageHandle, destX, destY, width, height, srcX, srcY); } - result = FileReadGIF(interp, dataSrc, "inline data", - format, imageHandle, destX, destY, width, height, srcX, srcY); - tsdPtr->fromData = 0; - return result; } - + /* *---------------------------------------------------------------------- * * ReadGIFHeader -- * - * This procedure reads the GIF header from the beginning of a - * GIF file and returns the dimensions of the image. + * This procedure reads the GIF header from the beginning of a GIF file + * and returns the dimensions of the image. * * Results: - * The return value is 1 if file "f" appears to start with - * a valid GIF header, 0 otherwise. If the header is valid, - * then *widthPtr and *heightPtr are modified to hold the - * dimensions of the image. + * The return value is 1 if file "f" appears to start with a valid GIF + * header, 0 otherwise. If the header is valid, then *widthPtr and + * *heightPtr are modified to hold the dimensions of the image. * * Side effects: * The access position in f advances. @@ -651,28 +670,29 @@ StringReadGIF(interp, dataObj, format, imageHandle, */ static int -ReadGIFHeader(chan, widthPtr, heightPtr) +ReadGIFHeader(gifConfPtr, chan, widthPtr, heightPtr) + GIFImageConfig *gifConfPtr; Tcl_Channel chan; /* Image file to read the header from */ - int *widthPtr, *heightPtr; /* The dimensions of the image are - * returned here. */ + int *widthPtr, *heightPtr; /* The dimensions of the image are returned + * here. */ { unsigned char buf[7]; - if ((Fread(buf, 1, 6, chan) != 6) + if ((Fread(gifConfPtr, buf, 1, 6, chan) != 6) || ((strncmp(GIF87a, (char *) buf, 6) != 0) && (strncmp(GIF89a, (char *) buf, 6) != 0))) { return 0; } - if (Fread(buf, 1, 4, chan) != 4) { + if (Fread(gifConfPtr, buf, 1, 4, chan) != 4) { return 0; } - *widthPtr = LM_to_uint(buf[0],buf[1]); - *heightPtr = LM_to_uint(buf[2],buf[3]); + *widthPtr = LM_to_uint(buf[0], buf[1]); + *heightPtr = LM_to_uint(buf[2], buf[3]); return 1; } - + /* *----------------------------------------------------------------- * The code below is copied from the giftoppm program and modified @@ -681,7 +701,8 @@ ReadGIFHeader(chan, widthPtr, heightPtr) */ static int -ReadColorMap(chan, number, buffer) +ReadColorMap(gifConfPtr, chan, number, buffer) + GIFImageConfig *gifConfPtr; Tcl_Channel chan; int number; unsigned char buffer[MAXCOLORMAPSIZE][4]; @@ -690,29 +711,28 @@ ReadColorMap(chan, number, buffer) unsigned char rgb[3]; for (i = 0; i < number; ++i) { - if (! ReadOK(chan, rgb, sizeof(rgb))) { + if (Fread(gifConfPtr, rgb, sizeof(rgb), 1, chan) <= 0) { return 0; } if (buffer) { - buffer[i][CM_RED] = rgb[0] ; - buffer[i][CM_GREEN] = rgb[1] ; - buffer[i][CM_BLUE] = rgb[2] ; - buffer[i][CM_ALPHA] = 255 ; + buffer[i][CM_RED] = rgb[0]; + buffer[i][CM_GREEN] = rgb[1]; + buffer[i][CM_BLUE] = rgb[2]; + buffer[i][CM_ALPHA] = 255; } } return 1; } - - - + static int -DoExtension(chan, label, transparent) +DoExtension(gifConfPtr, chan, label, buf, transparent) + GIFImageConfig *gifConfPtr; Tcl_Channel chan; int label; + unsigned char *buf; int *transparent; { - static unsigned char buf[256]; int count; switch (label) { @@ -724,12 +744,12 @@ DoExtension(chan, label, transparent) case 0xfe: /* Comment Extension */ do { - count = GetDataBlock(chan, (unsigned char*) buf); + count = GetDataBlock(gifConfPtr, chan, (unsigned char*) buf); } while (count > 0); return count; case 0xf9: /* Graphic Control Extension */ - count = GetDataBlock(chan, (unsigned char*) buf); + count = GetDataBlock(gifConfPtr, chan, (unsigned char*) buf); if (count < 0) { return 1; } @@ -738,53 +758,52 @@ DoExtension(chan, label, transparent) } do { - count = GetDataBlock(chan, (unsigned char*) buf); + count = GetDataBlock(gifConfPtr, chan, (unsigned char*) buf); } while (count > 0); return count; } do { - count = GetDataBlock(chan, (unsigned char*) buf); + count = GetDataBlock(gifConfPtr, chan, (unsigned char*) buf); } while (count > 0); return count; } - + static int -GetDataBlock(chan, buf) +GetDataBlock(gifConfPtr, chan, buf) + GIFImageConfig *gifConfPtr; Tcl_Channel chan; unsigned char *buf; { unsigned char count; - if (! ReadOK(chan, &count,1)) { + if (Fread(gifConfPtr, &count, 1, 1, chan) <= 0) { return -1; } - if ((count != 0) && (! ReadOK(chan, buf, count))) { + if ((count != 0) && (Fread(gifConfPtr, buf, count, 1, chan) <= 0)) { return -1; } return count; } - - /* *---------------------------------------------------------------------- * * ReadImage -- * - * Process a GIF image from a given source, with a given height, - * width, transparency, etc. + * Process a GIF image from a given source, with a given height, width, + * transparency, etc. * * This code is based on the code found in the ImageMagick GIF decoder, * which is (c) 2000 ImageMagick Studio. * * Some thoughts on our implementation: - * It sure would be nice if ReadImage didn't take 11 parameters! I think + * It sure would be nice if ReadImage didn't take 11 parameters! I think * that if we were smarter, we could avoid doing that. * - * Possible further optimizations: we could pull the GetCode function + * Possible further optimizations: we could pull the GetCode function * directly into ReadImage, which would improve our speed. * * Results: @@ -797,8 +816,9 @@ GetDataBlock(chan, buf) */ static int -ReadImage(interp, imagePtr, chan, len, rows, cmap, +ReadImage(gifConfPtr, interp, imagePtr, chan, len, rows, cmap, width, height, srcX, srcY, interlace, transparent) + GIFImageConfig *gifConfPtr; Tcl_Interp *interp; char *imagePtr; Tcl_Channel chan; @@ -816,16 +836,16 @@ ReadImage(interp, imagePtr, chan, len, rows, cmap, CONST static int interlaceStep[] = { 8, 8, 4, 2 }; CONST static int interlaceStart[] = { 0, 4, 2, 1 }; unsigned short prefix[(1 << MAX_LWZ_BITS)]; - unsigned char append[(1 << MAX_LWZ_BITS)]; - unsigned char stack[(1 << MAX_LWZ_BITS)*2]; + unsigned char append[(1 << MAX_LWZ_BITS)]; + unsigned char stack[(1 << MAX_LWZ_BITS)*2]; register unsigned char *top; int codeSize, clearCode, inCode, endCode, oldCode, maxCode; int code, firstCode; /* - * Initialize the decoder + * Initialize the decoder */ - if (! ReadOK(chan, &initialCodeSize, 1)) { + if (Fread(gifConfPtr, &initialCodeSize, 1, 1, chan) <= 0) { Tcl_AppendResult(interp, "error reading GIF image: ", Tcl_PosixError(interp), (char *) NULL); return TCL_ERROR; @@ -862,7 +882,7 @@ ReadImage(interp, imagePtr, chan, len, rows, cmap, } top = stack; - GetCode(chan, 0, 1); + GetCode(chan, 0, 1, gifConfPtr); /* * Read until we finish the image @@ -874,17 +894,17 @@ ReadImage(interp, imagePtr, chan, len, rows, cmap, /* * Bummer -- our stack is empty. Now we have to work! */ - code = GetCode(chan, codeSize, 0); + code = GetCode(chan, codeSize, 0, gifConfPtr); if (code < 0) { return TCL_OK; } if (code > maxCode || code == endCode) { /* - * If we're doing things right, we should never - * receive a code that is greater than our current - * maximum code. If we do, bail, because our decoder - * does not yet have that code set up. + * If we're doing things right, we should never receive a + * code that is greater than our current maximum code. If + * we do, bail, because our decoder does not yet have that + * code set up. * * If the code is the magic endCode value, quit. */ @@ -903,12 +923,12 @@ ReadImage(interp, imagePtr, chan, len, rows, cmap, if (oldCode == -1) { /* - * Last pass reset the decoder, so the first code we - * see must be a singleton. Seed the stack with it, - * and set up the old/first code pointers for - * insertion into the string table. We can't just - * roll this into the clearCode test above, because - * at that point we have not yet read the next code. + * Last pass reset the decoder, so the first code we see + * must be a singleton. Seed the stack with it, and set up + * the old/first code pointers for insertion into the + * string table. We can't just roll this into the + * clearCode test above, because at that point we have not + * yet read the next code. */ *top++ = append[code]; oldCode = code; @@ -921,8 +941,8 @@ ReadImage(interp, imagePtr, chan, len, rows, cmap, if (code == maxCode) { /* * maxCode is always one bigger than our highest assigned - * code. If the code we see is equal to maxCode, then - * we are about to add a new string to the table. ??? + * code. If the code we see is equal to maxCode, then we + * are about to add a new string to the table. ??? */ *top++ = firstCode; code = oldCode; @@ -930,8 +950,8 @@ ReadImage(interp, imagePtr, chan, len, rows, cmap, while (code > clearCode) { /* - * Populate the stack by tracing the string in the - * string table from its tail to its head + * Populate the stack by tracing the string in the string + * table from its tail to its head */ *top++ = append[code]; code = prefix[code]; @@ -959,11 +979,12 @@ ReadImage(interp, imagePtr, chan, len, rows, cmap, maxCode++; /* - * maxCode tells us the maximum code value we can accept. - * If we see that we need more bits to represent it than - * we are requesting from the unpacker, we need to increase - * the number we ask for. + * maxCode tells us the maximum code value we can accept. If + * we see that we need more bits to represent it than we are + * requesting from the unpacker, we need to increase the + * number we ask for. */ + if ((maxCode >= (1 << codeSize)) && (maxCode < (1<<MAX_LWZ_BITS))) { codeSize++; @@ -974,6 +995,7 @@ ReadImage(interp, imagePtr, chan, len, rows, cmap, /* * Pop the next color index off the stack. */ + v = *(--top); if (v < 0) { return TCL_OK; @@ -981,9 +1003,10 @@ ReadImage(interp, imagePtr, chan, len, rows, cmap, /* * If pixelPtr is null, we're skipping this image (presumably - * there are more in the file and we will be called to read - * one of them later) + * there are more in the file and we will be called to read one of + * them later) */ + *pixelPtr++ = cmap[v][CM_RED]; *pixelPtr++ = cmap[v][CM_GREEN]; *pixelPtr++ = cmap[v][CM_BLUE]; @@ -1013,7 +1036,6 @@ ReadImage(interp, imagePtr, chan, len, rows, cmap, } return TCL_OK; } - /* *---------------------------------------------------------------------- @@ -1021,19 +1043,18 @@ ReadImage(interp, imagePtr, chan, len, rows, cmap, * GetCode -- * * Extract the next compression code from the file. In GIF's, the - * compression codes are between 3 and 12 bits long and are then - * packed into 8 bit bytes, left to right, for example: + * compression codes are between 3 and 12 bits long and are then packed + * into 8 bit bytes, left to right, for example: * bbbaaaaa * dcccccbb * eeeedddd * ... - * We use a byte buffer read from the file and a sliding window - * to unpack the bytes. Thanks to ImageMagick for the sliding window - * idea. + * We use a byte buffer read from the file and a sliding window to unpack + * the bytes. Thanks to ImageMagick for the sliding window idea. * args: chan the channel to read from * code_size size of the code to extract - * flag boolean indicating whether the extractor - * should be reset or not + * flag boolean indicating whether the extractor should be + * reset or not * * Results: * code the next compression code @@ -1045,69 +1066,65 @@ ReadImage(interp, imagePtr, chan, len, rows, cmap, */ static int -GetCode(chan, code_size, flag) +GetCode(chan, code_size, flag, gifConfPtr) Tcl_Channel chan; int code_size; int flag; + GIFImageConfig *gifConfPtr; { - static unsigned char buf[280]; - static int bytes = 0, done; - static unsigned char *c; - - static unsigned int window; - static int bitsInWindow = 0; int ret; if (flag) { /* * Initialize the decoder. */ - bitsInWindow = 0; - bytes = 0; - window = 0; - done = 0; - c = NULL; + gifConfPtr->reader.bitsInWindow = 0; + gifConfPtr->reader.bytes = 0; + gifConfPtr->reader.window = 0; + gifConfPtr->reader.done = 0; + gifConfPtr->reader.c = NULL; return 0; } - while (bitsInWindow < code_size) { + while (gifConfPtr->reader.bitsInWindow < code_size) { /* * Not enough bits in our window to cover the request. */ - if (done) { + if (gifConfPtr->reader.done) { return -1; } - if (bytes == 0) { + if (gifConfPtr->reader.bytes == 0) { /* * Not enough bytes in our buffer to add to the window. */ - bytes = GetDataBlock(chan, buf); - c = buf; - if (bytes <= 0) { - done = 1; + gifConfPtr->reader.bytes = + GetDataBlock(gifConfPtr, chan, gifConfPtr->workingBuffer); + gifConfPtr->reader.c = gifConfPtr->reader.workingBuffer; + if (gifConfPtr->reader.bytes <= 0) { + gifConfPtr->reader.done = 1; break; } } /* * Tack another byte onto the window, see if that's enough. */ - window += (*c) << bitsInWindow; - c++; - bitsInWindow += 8; - bytes--; + gifConfPtr->reader.window += + (*gifConfPtr->reader.c) << gifConfPtr->reader.bitsInWindow; + gifConfPtr->reader.c++; + gifConfPtr->reader.bitsInWindow += 8; + gifConfPtr->reader.bytes--; } - /* * The next code will always be the last code_size bits of the window. */ - ret = window & ((1 << code_size) - 1); + ret = gifConfPtr->reader.window & ((1 << code_size) - 1); /* * Shift data in the window to put the next code at the end. */ - window >>= code_size; - bitsInWindow -= code_size; + gifConfPtr->reader.window >>= code_size; + gifConfPtr->reader.bitsInWindow -= code_size; return ret; } @@ -1116,25 +1133,27 @@ GetCode(chan, code_size, flag) * * Minit -- -- * - * This procedure initializes a base64 decoder handle + * This procedure initializes a base64 decoder handle * * Results: - * none + * None * * Side effects: - * the base64 handle is initialized + * The base64 handle is initialized * *---------------------------------------------------------------------- */ static void -mInit(string, handle) +mInit(string, handle, length) unsigned char *string; /* string containing initial mmencoded data */ MFile *handle; /* mmdecode "file" handle */ + int length; /* Number of bytes in string */ { handle->data = string; handle->state = 0; handle->c = 0; + handle->length = length; } /* @@ -1142,9 +1161,9 @@ mInit(string, handle) * * Mread -- * - * This procedure is invoked by the GIF file reader as a - * temporary replacement for "fread", to get GIF data out - * of a string (using Mgetc). + * This procedure is invoked by the GIF file reader as a temporary + * replacement for "fread", to get GIF data out of a string (using + * Mgetc). * * Results: * The return value is the number of characters "read" @@ -1165,14 +1184,14 @@ Mread(dst, chunkSize, numChunks, handle) register int i, c; int count = chunkSize * numChunks; - for(i=0; i<count && (c=Mgetc(handle)) != GIF_DONE; i++) { - *dst++ = c; + for (i=0; i<count && (c=Mgetc(handle)) != GIF_DONE; i++) { + *dst++ = c; } return i; } /* - * get the next decoded character from an mmencode handle + * Get the next decoded character from an mmencode handle. * This causes at least 1 character to be "read" from the encoded string */ @@ -1181,31 +1200,34 @@ Mread(dst, chunkSize, numChunks, handle) * * Mgetc -- * - * This procedure decodes and returns the next byte from a base64 - * encoded string. + * This procedure decodes and returns the next byte from a base64 encoded + * string. * * Results: - * The next byte (or GIF_DONE) is returned. + * The next byte (or GIF_DONE) is returned. * * Side effects: - * The base64 handle will change state. + * The base64 handle will change state. * *---------------------------------------------------------------------- */ static int Mgetc(handle) - MFile *handle; /* Handle containing decoder data and state */ + MFile *handle; /* Handle containing decoder data and state */ { int c; - int result = 0; /* Initialization needed only to prevent - * gcc compiler warning. */ + int result = 0; /* Initialization needed only to prevent gcc + * compiler warning. */ if (handle->state == GIF_DONE) { return GIF_DONE; } do { + if (handle->length-- <= 0) { + return GIF_DONE; + } c = char64(*handle->data); handle->data++; } while (c == GIF_SPACE); @@ -1242,20 +1264,21 @@ Mgetc(handle) * char64 -- * * This procedure converts a base64 ascii character into its binary - * equivalent. This code is a slightly modified version of the - * char64 proc in N. Borenstein's metamail decoder. + * equivalent. This code is a slightly modified version of the char64 + * proc in N. Borenstein's metamail decoder. * * Results: * The binary value, or an error code. * * Side effects: * None. + * *---------------------------------------------------------------------- */ static int char64(c) -int c; + int c; { switch(c) { case 'A': return 0; case 'B': return 1; case 'C': return 2; @@ -1297,37 +1320,42 @@ int c; * * Fread -- * - * This procedure calls either fread or Mread to read data - * from a file or a base64 encoded string. + * This procedure calls either fread or Mread to read data from a file or + * a base64 encoded string. * - * Results: - same as fread + * Results: - same as POSIX fread() or Tcl Tcl_Read() * *---------------------------------------------------------------------- */ static int -Fread(dst, hunk, count, chan) +Fread(gifConfPtr, dst, hunk, count, chan) + GIFImageConfig *gifConfPtr; unsigned char *dst; /* where to put the result */ - size_t hunk,count; /* how many */ + size_t hunk, count; /* how many */ Tcl_Channel chan; { - ThreadSpecificData *tsdPtr = (ThreadSpecificData *) - Tcl_GetThreadData(&dataKey, sizeof(ThreadSpecificData)); MFile *handle; - switch (tsdPtr->fromData) { - case 1: + if (gifConfPtr->fromData == INLINE_DATA_BASE64) { return Mread(dst, hunk, count, (MFile *) chan); - case 2: + } + + if (gifConfPtr->fromData == INLINE_DATA_BINARY) { handle = (MFile *) chan; + if (handle->length <= 0 || (size_t)handle->length < hunk*count) { + return -1; + } memcpy((VOID *)dst, (VOID *) handle->data, (size_t) (hunk * count)); handle->data += hunk * count; return (int)(hunk * count); - default: - return Tcl_Read(chan, (char *) dst, (int) (hunk * count)); } -} + /* + * Otherwise we've got a real file to read. + */ + return Tcl_Read(chan, (char *) dst, (int) (hunk * count)); +} /* * ChanWriteGIF - writes a image in GIF format. @@ -1346,21 +1374,21 @@ Fread(dst, hunk, count, chan) *---------------------------------------------------------------------- * FileWriteGIF- * - * This procedure is called by the photo image type to write - * GIF format data from a photo image into a given file + * This procedure is called by the photo image type to write GIF format + * data from a photo image into a given file * * Results: - * A standard TCL completion code. If TCL_ERROR is returned - * then an error message is left in interp->result. + * A standard TCL completion code. If TCL_ERROR is returned then an + * error message is left in interp->result. * *---------------------------------------------------------------------- */ - /* - * Types, defines and variables needed to write and compress a GIF. - */ +/* + * Types, defines and variables needed to write and compress a GIF. + */ -typedef int (* ifunptr) _ANSI_ARGS_((void)); +typedef int (* ifunptr) _ANSI_ARGS_((ClientData clientData)); #define LSB(a) ((unsigned char) (((short)(a)) & 0x00FF)) #define MSB(a) ((unsigned char) (((short)(a)) >> 8)) @@ -1368,32 +1396,37 @@ typedef int (* ifunptr) _ANSI_ARGS_((void)); #define GIFBITS 12 #define HSIZE 5003 /* 80% occupancy */ -static int ssize; -static int csize; -static int rsize; -static unsigned char *pixelo; -static int pixelSize; -static int pixelPitch; -static int greenOffset; -static int blueOffset; -static int alphaOffset; -static int num; -static unsigned char mapa[MAXCOLORMAPSIZE][3]; +typedef struct { + int ssize; + int csize; + int rsize; + unsigned char *pixelo; + int pixelSize; + int pixelPitch; + int greenOffset; + int blueOffset; + int alphaOffset; + int num; + unsigned char mapa[MAXCOLORMAPSIZE][3]; +} GifWriterState; /* - * Definition of new functions to write GIFs + * Definition of new functions to write GIFs */ -static int color _ANSI_ARGS_((int red,int green, int blue, - unsigned char mapa[MAXCOLORMAPSIZE][3])); -static void compress _ANSI_ARGS_((int init_bits, Tcl_Channel handle, - ifunptr readValue)); -static int nuevo _ANSI_ARGS_((int red, int green ,int blue, - unsigned char mapa[MAXCOLORMAPSIZE][3])); -static void savemap _ANSI_ARGS_((Tk_PhotoImageBlock *blockPtr, - unsigned char mapa[MAXCOLORMAPSIZE][3])); -static int ReadValue _ANSI_ARGS_((void)); - +static int color _ANSI_ARGS_((GifWriterState *statePtr, + int red, int green, int blue, + unsigned char mapa[MAXCOLORMAPSIZE][3])); +static void compress _ANSI_ARGS_((int initBits, Tcl_Channel handle, + ifunptr readValue, ClientData clientData)); +static int nuevo _ANSI_ARGS_((GifWriterState *statePtr, + int red, int green, int blue, + unsigned char mapa[MAXCOLORMAPSIZE][3])); +static void savemap _ANSI_ARGS_((GifWriterState *statePtr, + Tk_PhotoImageBlock *blockPtr, + unsigned char mapa[MAXCOLORMAPSIZE][3])); +static int ReadValue _ANSI_ARGS_((ClientData clientData)); + static int FileWriteGIF(interp, filename, format, blockPtr) Tcl_Interp *interp; /* Interpreter to use for reporting errors. */ @@ -1408,20 +1441,20 @@ FileWriteGIF(interp, filename, format, blockPtr) if (!chan) { return TCL_ERROR; } - if (Tcl_SetChannelOption(interp, chan, "-translation", "binary") != TCL_OK) { + if (Tcl_SetChannelOption(interp, chan, "-translation", + "binary") != TCL_OK) { Tcl_Close(NULL, chan); return TCL_ERROR; } result = CommonWriteGIF(interp, chan, format, blockPtr); + if (Tcl_Close(interp, chan) == TCL_ERROR) { return TCL_ERROR; } return result; } - -#define Mputc(c,handle) Tcl_Write(handle,(char *) &c,1) - + static int CommonWriteGIF(interp, handle, format, blockPtr) Tcl_Interp *interp; @@ -1429,146 +1462,149 @@ CommonWriteGIF(interp, handle, format, blockPtr) Tcl_Obj *format; Tk_PhotoImageBlock *blockPtr; { - int resolution; - - long width,height,x; + GifWriteState state, *statePtr = &state; + int resolution; + long width, height, x; unsigned char c; - unsigned int top,left; + unsigned int top, left; top = 0; left = 0; - pixelSize = blockPtr->pixelSize; - greenOffset = blockPtr->offset[1]-blockPtr->offset[0]; - blueOffset = blockPtr->offset[2]-blockPtr->offset[0]; - alphaOffset = blockPtr->offset[0]; - if (alphaOffset < blockPtr->offset[2]) { - alphaOffset = blockPtr->offset[2]; + memset(statePtr, 0, sizeof(state)); + + statePtr->pixelSize = blockPtr->pixelSize; + statePtr->greenOffset = blockPtr->offset[1]-blockPtr->offset[0]; + statePtr->blueOffset = blockPtr->offset[2]-blockPtr->offset[0]; + statePtr->alphaOffset = blockPtr->offset[0]; + if (statePtr->alphaOffset < blockPtr->offset[2]) { + statePtr->alphaOffset = blockPtr->offset[2]; } - if (++alphaOffset < pixelSize) { - alphaOffset -= blockPtr->offset[0]; + if (++statePtr->alphaOffset < statePtr->pixelSize) { + statePtr->alphaOffset -= blockPtr->offset[0]; } else { - alphaOffset = 0; + statePtr->alphaOffset = 0; } - Tcl_Write(handle, (char *) (alphaOffset ? GIF89a : GIF87a), 6); + Tcl_Write(handle, (char *) (statePtr->alphaOffset ? GIF89a : GIF87a), 6); for (x=0 ; x<MAXCOLORMAPSIZE ; x++) { - mapa[x][CM_RED] = 255; - mapa[x][CM_GREEN] = 255; - mapa[x][CM_BLUE] = 255; + statePtr->mapa[x][CM_RED] = 255; + statePtr->mapa[x][CM_GREEN] = 255; + statePtr->mapa[x][CM_BLUE] = 255; } width = blockPtr->width; height = blockPtr->height; - pixelo = blockPtr->pixelPtr + blockPtr->offset[0]; - pixelPitch = blockPtr->pitch; - savemap(blockPtr,mapa); - if (num >= MAXCOLORMAPSIZE) { + statePtr->pixelo = blockPtr->pixelPtr + blockPtr->offset[0]; + statePtr->pixelPitch = blockPtr->pitch; + savemap(statePtr, blockPtr, statePtr->mapa); + if (statePtr->num >= MAXCOLORMAPSIZE) { Tcl_AppendResult(interp, "too many colors", (char *) NULL); return TCL_ERROR; } - if (num<2) { - num = 2; + if (statePtr->num<2) { + statePtr->num = 2; } c = LSB(width); - Mputc(c,handle); + Tcl_Write(handle, (char *) &c, 1); c = MSB(width); - Mputc(c,handle); + Tcl_Write(handle, (char *) &c, 1); c = LSB(height); - Mputc(c,handle); + Tcl_Write(handle, (char *) &c, 1); c = MSB(height); - Mputc(c,handle); + Tcl_Write(handle, (char *) &c, 1); resolution = 0; - while (num >> resolution) { + while (statePtr->num >> resolution) { resolution++; } c = 111 + resolution * 17; - Mputc(c,handle); + Tcl_Write(handle, (char *) &c, 1); - num = 1 << resolution; + statePtr->num = 1 << resolution; /* * background color */ c = 0; - Mputc(c,handle); + Tcl_Write(handle, (char *) &c, 1); /* * zero for future expansion. */ - Mputc(c,handle); + Tcl_Write(handle, (char *) &c, 1); - for (x=0 ; x<num ; x++) { - c = mapa[x][CM_RED]; - Mputc(c,handle); - c = mapa[x][CM_GREEN]; - Mputc(c,handle); - c = mapa[x][CM_BLUE]; - Mputc(c,handle); + for (x=0 ; x<statePtr->num ; x++) { + c = statePtr->mapa[x][CM_RED]; + Tcl_Write(handle, (char *) &c, 1); + c = statePtr->mapa[x][CM_GREEN]; + Tcl_Write(handle, (char *) &c, 1); + c = statePtr->mapa[x][CM_BLUE]; + Tcl_Write(handle, (char *) &c, 1); } /* * Write out extension for transparent colour index, if necessary. */ - if (alphaOffset) { + if (statePtr->alphaOffset) { c = GIF_EXTENSION; - Mputc(c, handle); + Tcl_Write(handle, (char *) &c, 1); Tcl_Write(handle, "\371\4\1\0\0\0", 7); } c = GIF_START; - Mputc(c,handle); + Tcl_Write(handle, (char *) &c, 1); c = LSB(top); - Mputc(c,handle); + Tcl_Write(handle, (char *) &c, 1); c = MSB(top); - Mputc(c,handle); + Tcl_Write(handle, (char *) &c, 1); c = LSB(left); - Mputc(c,handle); + Tcl_Write(handle, (char *) &c, 1); c = MSB(left); - Mputc(c,handle); + Tcl_Write(handle, (char *) &c, 1); c = LSB(width); - Mputc(c,handle); + Tcl_Write(handle, (char *) &c, 1); c = MSB(width); - Mputc(c,handle); + Tcl_Write(handle, (char *) &c, 1); c = LSB(height); - Mputc(c,handle); + Tcl_Write(handle, (char *) &c, 1); c = MSB(height); - Mputc(c,handle); + Tcl_Write(handle, (char *) &c, 1); c = 0; - Mputc(c,handle); + Tcl_Write(handle, (char *) &c, 1); c = resolution; - Mputc(c,handle); + Tcl_Write(handle, (char *) &c, 1); - ssize = rsize = blockPtr->width; - csize = blockPtr->height; - compress(resolution+1, handle, ReadValue); + statePtr->ssize = statePtr->rsize = blockPtr->width; + statePtr->csize = blockPtr->height; + compress(resolution+1, handle, ReadValue, (ClientData) statePtr); c = 0; - Mputc(c,handle); + Tcl_Write(handle, (char *) &c, 1); c = GIF_TERMINATOR; - Mputc(c,handle); + Tcl_Write(handle, (char *) &c, 1); return TCL_OK; } - + static int -color(red, green, blue, mapa) +color(statePtr, red, green, blue, mapa) + GifWriterState *statePtr; int red; int green; int blue; unsigned char mapa[MAXCOLORMAPSIZE][3]; { int x; - for (x=(alphaOffset != 0) ; x<=MAXCOLORMAPSIZE ; x++) { + for (x=(statePtr->alphaOffset != 0) ; x<=MAXCOLORMAPSIZE ; x++) { if ((mapa[x][CM_RED] == red) && (mapa[x][CM_GREEN] == green) && (mapa[x][CM_BLUE] == blue)) { return x; @@ -1576,15 +1612,15 @@ color(red, green, blue, mapa) } return -1; } - static int -nuevo(red, green, blue, mapa) - int red,green,blue; +nuevo(statePtr, red, green, blue, mapa) + GifWriterState *statePtr; + int red, green, blue; unsigned char mapa[MAXCOLORMAPSIZE][3]; { - int x = (alphaOffset != 0); - for (; x<=num ; x++) { + int x = (statePtr->alphaOffset != 0); + for (; x<=statePtr->num ; x++) { if ((mapa[x][CM_RED] == red) && (mapa[x][CM_GREEN] == green) && (mapa[x][CM_BLUE] == blue)) { return 0; @@ -1592,74 +1628,77 @@ nuevo(red, green, blue, mapa) } return 1; } - + static void -savemap(blockPtr,mapa) +savemap(statePtr, blockPtr, mapa) + GifWriterState *statePtr; Tk_PhotoImageBlock *blockPtr; unsigned char mapa[MAXCOLORMAPSIZE][3]; { unsigned char *colores; - int x,y; - unsigned char red,green,blue; + int x, y; + unsigned char red, green, blue; - if (alphaOffset) { - num = 0; + if (statePtr->alphaOffset) { + statePtr->num = 0; mapa[0][CM_RED] = 0xd9; mapa[0][CM_GREEN] = 0xd9; mapa[0][CM_BLUE] = 0xd9; } else { - num = -1; + statePtr->num = -1; } for(y=0 ; y<blockPtr->height ; y++) { - colores = blockPtr->pixelPtr + blockPtr->offset[0] - + y * blockPtr->pitch; + colores = blockPtr->pixelPtr + blockPtr->offset[0] + y*blockPtr->pitch; for(x=0 ; x<blockPtr->width ; x++) { - if (!alphaOffset || (colores[alphaOffset] != 0)) { + if (!statePtr->alphaOffset || colores[statePtr->alphaOffset]!=0) { red = colores[0]; - green = colores[greenOffset]; - blue = colores[blueOffset]; - if (nuevo(red,green,blue,mapa)) { - num++; - if (num >= MAXCOLORMAPSIZE) { + green = colores[statePtr->greenOffset]; + blue = colores[statePtr->blueOffset]; + if (nuevo(statePtr, red, green, blue, mapa)) { + statePtr->num++; + if (statePtr->num >= MAXCOLORMAPSIZE) { return; } - mapa[num][CM_RED] = red; - mapa[num][CM_GREEN] = green; - mapa[num][CM_BLUE] = blue; + mapa[statePtr->num][CM_RED] = red; + mapa[statePtr->num][CM_GREEN] = green; + mapa[statePtr->num][CM_BLUE] = blue; } } - colores += pixelSize; + colores += statePtr->pixelSize; } } return; } - + static int -ReadValue() +ReadValue(clientData) + ClientData clientData; { + GifWriterState *statePtr = (GifWriterState *) clientData; unsigned int col; - if (csize == 0) { + if (statePtr->csize == 0) { return EOF; } - if (alphaOffset && (pixelo[alphaOffset] == 0)) { + if (statePtr->alphaOffset && statePtr->pixelo[statePtr->alphaOffset]==0) { col = 0; } else { - col = color(pixelo[0], pixelo[greenOffset], pixelo[blueOffset], mapa); + col = color(statePtr, statePtr->pixelo[0], + statePtr->pixelo[statePtr->greenOffset], + statePtr->pixelo[statePtr->blueOffset], statePtr->mapa); } - pixelo += pixelSize; - if (--ssize <= 0) { - ssize = rsize; - csize--; - pixelo += pixelPitch - (rsize * pixelSize); + statePtr->pixelo += statePtr->pixelSize; + if (--statePtr->ssize <= 0) { + statePtr->ssize = statePtr->rsize; + statePtr->csize--; + statePtr->pixelo += statePtr->pixelPitch + - (statePtr->rsize * statePtr->pixelSize); } return col; } - - /* *----------------------------------------------------------------------- * @@ -1671,30 +1710,27 @@ ReadValue() * http://www.hasc.com * info@hasc.com * - * Permission to use, copy, modify, and distribute this software and - * its documentation for any purpose and without fee is hereby - * granted, provided that the above copyright notice appear in all - * copies and that both that copyright notice and this permission - * notice appear in supporting documentation. This software is - * provided "AS IS." The Hutchison Avenue Software Corporation - * disclaims all warranties, either express or implied, including but - * not limited to implied warranties of merchantability and fitness - * for a particular purpose, with respect to this code and + * Permission to use, copy, modify, and distribute this software and its + * documentation for any purpose and without fee is hereby granted, provided + * that the above copyright notice appear in all copies and that both that + * copyright notice and this permission notice appear in supporting + * documentation. This software is provided "AS IS." The Hutchison Avenue + * Software Corporation disclaims all warranties, either express or implied, + * including but not limited to implied warranties of merchantability and + * fitness for a particular purpose, with respect to this code and * accompanying documentation. * - * The miGIF compression routines do not, strictly speaking, generate - * files conforming to the GIF spec, since the image data is not - * LZW-compressed (this is the point: in order to avoid transgression - * of the Unisys patent on the LZW algorithm.) However, miGIF - * generates data streams that any reasonably sane LZW decompresser - * will decompress to what we want. - * - * miGIF compression uses run length encoding. It compresses - * horizontal runs of pixels of the same color. This type of - * compression gives good results on images with many runs, for - * example images with lines, text and solid shapes on a solid-colored - * background. It gives little or no compression on images with few - * runs, for example digital or scanned photos. + * The miGIF compression routines do not, strictly speaking, generate files + * conforming to the GIF spec, since the image data is not LZW-compressed + * (this is the point: in order to avoid transgression of the Unisys patent on + * the LZW algorithm.) However, miGIF generates data streams that any + * reasonably sane LZW decompresser will decompress to what we want. + * + * miGIF compression uses run length encoding. It compresses horizontal runs + * of pixels of the same color. This type of compression gives good results on + * images with many runs, for example images with lines, text and solid shapes + * on a solid-colored background. It gives little or no compression on images + * with few runs, for example digital or scanned photos. * * der Mouse * mouse@rodents.montreal.qc.ca @@ -1702,35 +1738,36 @@ ReadValue() * * ivo@hasc.com * - * The Graphics Interchange Format(c) is the Copyright property of - * CompuServe Incorporated. GIF(sm) is a Service Mark property of - * CompuServe Incorporated. + * The Graphics Interchange Format(c) is the Copyright property of CompuServe + * Incorporated. GIF(sm) is a Service Mark property of CompuServe Incorporated. * *----------------------------------------------------------------------- */ -static int rl_pixel; -static int rl_basecode; -static int rl_count; -static int rl_table_pixel; -static int rl_table_max; -static int just_cleared; -static int out_bits; -static int out_bits_init; -static int out_count; -static int out_bump; -static int out_bump_init; -static int out_clear; -static int out_clear_init; -static int max_ocodes; -static int code_clear; -static int code_eof; -static unsigned int obuf; -static int obits; -static Tcl_Channel ofile; -static unsigned char oblock[256]; -static int oblen; - +typedef struct { + int runlengthPixel; + int runlengthBaseCode; + int runlengthCount; + int runlengthTablePixel; + int runlengthTableMax; + int justCleared; + int outputBits; + int outputBitsInit; + int outputCount; + int outputBump; + int outputBumpInit; + int outputClear; + int outputClearInit; + int maxOcodes; + int codeClear; + int codeEOF; + unsigned int obuf; + int obits; + Tcl_Channel ofile; + unsigned char oblock[256]; + int oblen; +} miGIFState_t; + /* * Used only when debugging GIF compression code */ @@ -1738,20 +1775,25 @@ static int oblen; #ifdef MIGIF_DEBUGGING_ENVARS -static int verbose_set = 0; +/* + * This debugging code is _absolutely_ not thread-safe. It's also not normally + * enabled either. + */ + +static int verboseSet = 0; static int verbose; -#define MIGIF_VERBOSE (verbose_set?verbose:set_verbose()) -#define DEBUGMSG(printf_args) if (MIGIF_VERBOSE) { printf printf_args; } +#define MIGIF_VERBOSE (verboseSet?verbose:setVerbose()) +#define DEBUGMSG(printfArgs) if (MIGIF_VERBOSE) { printf printfArgs; } static int -set_verbose(void) +setVerbose(void) { verbose = !!getenv("MIGIF_VERBOSE"); - verbose_set = 1; + verboseSet = 1; return verbose; } -static CONST char * +static const char * binformat(v, nbits) unsigned int v; int nbits; @@ -1776,109 +1818,116 @@ binformat(v, nbits) *bp = '\0'; return &bufs[bhand][0]; } - -#else - -#define MIGIF_VERBOSE 0 -#define DEBUGMSG(printf_args) /* do nothing */ - +#else /* !MIGIF_DEBUGGING_ENVARS */ +#define DEBUGMSG(printfArgs) /* do nothing */ #endif - + static void -write_block() +writeBlock(statePtr) + miGIFState_t *statePtr; { int i; unsigned char c; +#ifdef MIGIF_DEBUGGING_ENVARS if (MIGIF_VERBOSE) { - printf("write_block %d:", oblen); - for (i=0 ; i<oblen ; i++) { - printf(" %02x", oblock[i]); + printf("writeBlock %d:", statePtr->oblen); + for (i=0 ; i<statePtr->oblen ; i++) { + printf(" %02x", statePtr->oblock[i]); } printf("\n"); } - c = oblen; - Tcl_Write(ofile, (char *) &c, 1); - Tcl_Write(ofile, (char *) &oblock[0], oblen); - oblen = 0; +#endif + c = statePtr->oblen; + Tcl_Write(statePtr->ofile, (char *) &c, 1); + Tcl_Write(statePtr->ofile, (char *) &statePtr->oblock[0], statePtr->oblen); + statePtr->oblen = 0; } - + static void -block_out(c) +blockOut(statePtr, c) + miGIFState_t *statePtr; unsigned char c; { - DEBUGMSG(("block_out %s\n", binformat(c, 8))); - oblock[oblen++] = c; - if (oblen >= 255) { - write_block(); + DEBUGMSG(("blockOut %s\n", binformat(c, 8))); + statePtr->oblock[statePtr->oblen++] = c; + if (statePtr->oblen >= 255) { + writeBlock(statePtr); } } - + static void -block_flush() +blockFlush(statePtr) + miGIFState_t *statePtr; { - DEBUGMSG(("block_flush\n")); - if (oblen > 0) { - write_block(); + DEBUGMSG(("blockFlush\n")); + if (statePtr->oblen > 0) { + writeBlock(statePtr); } } - + static void -output(val) +output(statePtr, val) + miGIFState_t *statePtr; int val; { - DEBUGMSG(("output %s [%s %d %d]\n", binformat(val, out_bits), - binformat(obuf, obits), obits, out_bits)); - obuf |= val << obits; - obits += out_bits; - while (obits >= 8) { - block_out(obuf&0xff); - obuf >>= 8; - obits -= 8; - } - DEBUGMSG(("output leaving [%s %d]\n", binformat(obuf, obits), obits)); + DEBUGMSG(("output %s [%s %d %d]\n", binformat(val, statePtr->outputBits), + binformat(statePtr->obuf, statePtr->obits), statePtr->obits, + statePtr->outputBits)); + statePtr->obuf |= val << statePtr->obits; + statePtr->obits += statePtr->outputBits; + while (statePtr->obits >= 8) { + blockOut(statePtr, statePtr->obuf&0xff); + statePtr->obuf >>= 8; + statePtr->obits -= 8; + } + DEBUGMSG(("output leaving [%s %d]\n", + binformat(statePtr->obuf, statePtr->obits), statePtr->obits)); } - + static void -output_flush() +outputFlush(statePtr) + miGIFState_t *statePtr; { - DEBUGMSG(("output_flush\n")); - if (obits > 0) { - block_out(obuf); + DEBUGMSG(("outputFlush\n")); + if (statePtr->obits > 0) { + blockOut(statePtr, statePtr->obuf); } - block_flush(); + blockFlush(statePtr); } - + static void -did_clear() +didClear(statePtr) + miGIFState_t *statePtr; { - DEBUGMSG(("did_clear\n")); - out_bits = out_bits_init; - out_bump = out_bump_init; - out_clear = out_clear_init; - out_count = 0; - rl_table_max = 0; - just_cleared = 1; + DEBUGMSG(("didClear\n")); + statePtr->outputBits = statePtr->outputBitsInit; + statePtr->outputBump = statePtr->outputBumpInit; + statePtr->outputClear = statePtr->outputClearInit; + statePtr->outputCount = 0; + statePtr->runlengthTableMax = 0; + statePtr->justCleared = 1; } - + static void -output_plain(c) +outputPlain(statePtr, c) + miGIFState_t *statePtr; int c; { - DEBUGMSG(("output_plain %s\n", binformat(c, out_bits))); - just_cleared = 0; - output(c); - out_count++; - if (out_count >= out_bump) { - out_bits++; - out_bump += 1 << (out_bits - 1); - } - if (out_count >= out_clear) { - output(code_clear); - did_clear(); + DEBUGMSG(("outputPlain %s\n", binformat(c, statePtr->outputBits))); + statePtr->justCleared = 0; + output(statePtr, c); + statePtr->outputCount++; + if (statePtr->outputCount >= statePtr->outputBump) { + statePtr->outputBits++; + statePtr->outputBump += 1 << (statePtr->outputBits - 1); + } + if (statePtr->outputCount >= statePtr->outputClear) { + output(statePtr, statePtr->codeClear); + didClear(statePtr); } } - + static unsigned int isqrt(x) unsigned int x; @@ -1898,9 +1947,9 @@ isqrt(x) r = v; } } - + static unsigned int -compute_triangle_count(count, nrepcodes) +computeTriangleCount(count, nrepcodes) unsigned int count; unsigned int nrepcodes; { @@ -1926,196 +1975,213 @@ compute_triangle_count(count, nrepcodes) } return cost; } - + static void -max_out_clear() +maxOutputClear(statePtr) + miGIFState_t *statePtr; { - out_clear = max_ocodes; + statePtr->outputClear = statePtr->maxOcodes; } - + static void -reset_out_clear() +resetOutputClear(statePtr) + miGIFState_t *statePtr; { - out_clear = out_clear_init; - if (out_count >= out_clear) { - output(code_clear); - did_clear(); + statePtr->outputClear = statePtr->outputClearInit; + if (statePtr->outputCount >= statePtr->outputClear) { + output(statePtr, statePtr->codeClear); + didClear(statePtr); } } - + static void -rl_flush_fromclear(count) +runlengthFlushFromClear(statePtr, count) + miGIFState_t *statePtr; int count; { int n; - DEBUGMSG(("rl_flush_fromclear %d\n", count)); - max_out_clear(); - rl_table_pixel = rl_pixel; + DEBUGMSG(("runlengthFlushFromClear %d\n", count)); + maxOutputClear(statePtr); + statePtr->runlengthTablePixel = statePtr->runlengthPixel; n = 1; while (count > 0) { if (n == 1) { - rl_table_max = 1; - output_plain(rl_pixel); + statePtr->runlengthTableMax = 1; + outputPlain(statePtr, statePtr->runlengthPixel); count--; } else if (count >= n) { - rl_table_max = n; - output_plain(rl_basecode+n-2); + statePtr->runlengthTableMax = n; + outputPlain(statePtr, statePtr->runlengthBaseCode+n-2); count -= n; } else if (count == 1) { - rl_table_max++; - output_plain(rl_pixel); + statePtr->runlengthTableMax++; + outputPlain(statePtr, statePtr->runlengthPixel); count = 0; } else { - rl_table_max++; - output_plain(rl_basecode+count-2); + statePtr->runlengthTableMax++; + outputPlain(statePtr, statePtr->runlengthBaseCode+count-2); count = 0; } - if (out_count == 0) { + if (statePtr->outputCount == 0) { n = 1; } else { n++; } } - reset_out_clear(); - DEBUGMSG(("rl_flush_fromclear leaving table_max=%d\n", rl_table_max)); + resetOutputClear(statePtr); + DEBUGMSG(("runlengthFlushFromClear leaving tableMax=%d\n", + statePtr->runlengthTableMax)); } - + static void -rl_flush_clearorrep(count) +runlengthFlushClearOrRep(statePtr, count) + miGIFState_t *statePtr; int count; { int withclr; - DEBUGMSG(("rl_flush_clearorrep %d\n", count)); - withclr = 1 + compute_triangle_count(count, max_ocodes); + DEBUGMSG(("runlengthFlushClearOrRep %d\n", count)); + withclr = 1 + computeTriangleCount(count, statePtr->maxOcodes); if (withclr < count) { - output(code_clear); - did_clear(); - rl_flush_fromclear(count); + output(statePtr, statePtr->codeClear); + didClear(statePtr); + runlengthFlushFromClear(statePtr, count); } else { for (; count>0 ; count--) { - output_plain(rl_pixel); + outputPlain(statePtr, statePtr->runlengthPixel); } } } - + static void -rl_flush_withtable(count) +runlengthFlushWithTable(statePtr, count) + miGIFState_t *statePtr; int count; { int repmax; int repleft; int leftover; - DEBUGMSG(("rl_flush_withtable %d\n", count)); - repmax = count / rl_table_max; - leftover = count % rl_table_max; + DEBUGMSG(("runlengthFlushWithTable %d\n", count)); + repmax = count / statePtr->runlengthTableMax; + leftover = count % statePtr->runlengthTableMax; repleft = (leftover ? 1 : 0); - if (out_count+repmax+repleft > max_ocodes) { - repmax = max_ocodes - out_count; - leftover = count - (repmax * rl_table_max); - repleft = 1 + compute_triangle_count(leftover, max_ocodes); + if (statePtr->outputCount+repmax+repleft > statePtr->maxOcodes) { + repmax = statePtr->maxOcodes - statePtr->outputCount; + leftover = count - (repmax * statePtr->runlengthTableMax); + repleft = 1 + computeTriangleCount(leftover, statePtr->maxOcodes); } - DEBUGMSG(("rl_flush_withtable repmax=%d leftover=%d repleft=%d\n", + DEBUGMSG(("runlengthFlushWithTable repmax=%d leftover=%d repleft=%d\n", repmax, leftover, repleft)); - if (1+(int)compute_triangle_count(count, max_ocodes) < repmax+repleft) { - output(code_clear); - did_clear(); - rl_flush_fromclear(count); + if (1+(int)computeTriangleCount(count, statePtr->maxOcodes) + < repmax+repleft) { + output(statePtr, statePtr->codeClear); + didClear(statePtr); + runlengthFlushFromClear(statePtr, count); return; } - max_out_clear(); + maxOutputClear(statePtr); for (; repmax>0 ; repmax--) { - output_plain(rl_basecode + rl_table_max - 2); + outputPlain(statPtr, + statePtr->runlengthBaseCode + statePtr->runlengthTableMax - 2); } if (leftover) { - if (just_cleared) { - rl_flush_fromclear(leftover); + if (statePtr->justCleared) { + runlengthFlushFromClear(statePtr, leftover); } else if (leftover == 1) { - output_plain(rl_pixel); + outputPlain(statePtr, statePtr->runlengthPixel); } else { - output_plain(rl_basecode + leftover - 2); + outputPlain(statePtr, statePtr->runlengthBaseCode + leftover - 2); } } - reset_out_clear(); + resetOutputClear(statePtr); } - + static void -rl_flush() +runlengthFlush(statePtr) + miGIFState_t *statePtr; { - DEBUGMSG(("rl_flush [ %d %d\n", rl_count, rl_pixel)); - if (rl_count == 1) { - output_plain(rl_pixel); - rl_count = 0; - DEBUGMSG(("rl_flush ]\n")); + DEBUGMSG(("runlengthFlush [ %d %d\n", statePtr->runlengthCount, + statePtr->runlengthPixel)); + if (statePtr->runlengthCount == 1) { + outputPlain(statePtr, statePtr->runlengthPixel); + statePtr->runlengthCount = 0; + DEBUGMSG(("runlengthFlush ]\n")); return; } - if (just_cleared) { - rl_flush_fromclear(rl_count); - } else if ((rl_table_max < 2) || (rl_table_pixel != rl_pixel)) { - rl_flush_clearorrep(rl_count); + if (statePtr->justCleared) { + runlengthFlushFromClear(statePtr, statePtr->runlengthCount); + } else if ((statePtr->runlengthTableMax < 2) + || (statePtr->runlengthTablePixel != statePtr->runlengthPixel)) { + runlengthFlushClearOrRep(statePtr, statePtr->runlengthCount); } else { - rl_flush_withtable(rl_count); + runlengthFlushWithTable(statePtr, statePtr->runlengthCount); } - DEBUGMSG(("rl_flush ]\n")); - rl_count = 0; + DEBUGMSG(("runlengthFlush ]\n")); + statePtr->runlengthCount = 0; } - - + static void -compress(init_bits, handle, readValue) - int init_bits; +compress(initBits, handle, readValue, clientData) + int initBits; Tcl_Channel handle; ifunptr readValue; + ClientData clientData; { int c; - - ofile = handle; - obuf = 0; - obits = 0; - oblen = 0; - code_clear = 1 << (init_bits - 1); - code_eof = code_clear + 1; - rl_basecode = code_eof + 1; - out_bump_init = (1 << (init_bits - 1)) - 1; + miGIFState_t state, *statePtr = &state; + + memset(statePtr, 0, sizeof(state)); + + statePtr->ofile = handle; + statePtr->obuf = 0; + statePtr->obits = 0; + statePtr->oblen = 0; + statePtr->codeClear = 1 << (initBits - 1); + statePtr->codeEOF = statePtr->codeClear + 1; + statePtr->runlengthBaseCode = statePtr->codeEOF + 1; + statePtr->outputBumpInit = (1 << (initBits - 1)) - 1; /* - * For images with a lot of runs, making out_clear_init larger - * will give better compression. + * For images with a lot of runs, making outputClearInit larger will give + * better compression. */ - out_clear_init = (init_bits <= 3) ? 9 : (out_bump_init-1); + statePtr->outputClearInit = + (initBits <= 3) ? 9 : (statePtr->outputBumpInit-1); #ifdef MIGIF_DEBUGGING_ENVARS { const char *ocienv; ocienv = getenv("MIGIF_OUT_CLEAR_INIT"); if (ocienv) { - out_clear_init = atoi(ocienv); - DEBUGMSG(("[overriding out_clear_init to %d]\n", out_clear_init)); + statePtr->outputClearInit = atoi(ocienv); + DEBUGMSG(("[overriding outputClearInit to %d]\n", + statePtr->outputClearInit)); } } #endif - out_bits_init = init_bits; - max_ocodes = (1 << GIFBITS) - ((1 << (out_bits_init - 1)) + 3); - did_clear(); - output(code_clear); - rl_count = 0; + statePtr->outputBitsInit = initBits; + statePtr->maxOcodes = + (1 << GIFBITS) - ((1 << (statePtr->outputBitsInit - 1)) + 3); + didClear(statePtr); + output(statePtr, statePtr->codeClear); + statePtr->runlengthCount = 0; while (1) { - c = readValue(); - if ((rl_count > 0) && (c != rl_pixel)) { - rl_flush(); + c = readValue(clientData); + if (statePtr->runlengthCount>0 && statePtr->runlengthPixel!=c) { + runlengthFlush(statePtr); } if (c == EOF) { break; } - if (rl_pixel == c) { - rl_count++; + if (statePtr->runlengthPixel == c) { + statePtr->runlengthCount++; } else { - rl_pixel = c; - rl_count = 1; + statePtr->runlengthPixel = c; + statePtr->runlengthCount = 1; } } - output(code_eof); - output_flush(); + output(statePtr, statePtr->codeEOF); + outputFlush(statePtr); } /* |