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-rw-r--r--generic/tkImgGIF.c325
1 files changed, 177 insertions, 148 deletions
diff --git a/generic/tkImgGIF.c b/generic/tkImgGIF.c
index 9a823bf..69a0c85 100644
--- a/generic/tkImgGIF.c
+++ b/generic/tkImgGIF.c
@@ -32,7 +32,7 @@
* 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 1.43 2008/04/09 21:00:54 nijtmans Exp $
+ * RCS: @(#) $Id: tkImgGIF.c,v 1.44 2008/04/27 22:38:56 dkf Exp $
*/
#include "tkInt.h"
@@ -1647,7 +1647,8 @@ color(
int x = (statePtr->alphaOffset != 0);
for (; x<=MAXCOLORMAPSIZE ; x++) {
- if ((statePtr->mapa[x][CM_RED] == red) && (statePtr->mapa[x][CM_GREEN] == green) &&
+ if ((statePtr->mapa[x][CM_RED] == red) &&
+ (statePtr->mapa[x][CM_GREEN] == green) &&
(statePtr->mapa[x][CM_BLUE] == blue)) {
return x;
}
@@ -1663,7 +1664,8 @@ nuevo(
int x = (statePtr->alphaOffset != 0);
for (; x<=statePtr->num ; x++) {
- if ((statePtr->mapa[x][CM_RED] == red) && (statePtr->mapa[x][CM_GREEN] == green) &&
+ if ((statePtr->mapa[x][CM_RED] == red) &&
+ (statePtr->mapa[x][CM_GREEN] == green) &&
(statePtr->mapa[x][CM_BLUE] == blue)) {
return 0;
}
@@ -1739,7 +1741,6 @@ ReadValue(
}
/*
- *
* GIF Image compression - modified 'compress'
*
* Based on: compress.c - File compression ala IEEE Computer, June 1984.
@@ -1750,55 +1751,54 @@ ReadValue(
* Ken Turkowski (decvax!decwrl!turtlevax!ken)
* James A. Woods (decvax!ihnp4!ames!jaw)
* Joe Orost (decvax!vax135!petsd!joe)
- *
*/
#define MAXCODE(n_bits) (((long) 1 << (n_bits)) - 1)
typedef struct {
- int n_bits; /* number of bits/code */
+ int n_bits; /* number of bits/code */
long maxcode; /* maximum code, given n_bits */
- int htab[HSIZE];
- unsigned int codetab[HSIZE];
+ int htab[HSIZE];
+ unsigned int codetab[HSIZE];
+ long hsize; /* for dynamic table sizing */
- long hsize; /* for dynamic table sizing */
+ /*
+ * To save much memory, we overlay the table used by compress() with those
+ * used by decompress(). The tab_prefix table is the same size and type as
+ * the codetab. The tab_suffix table needs 2**GIFBITS characters. We get
+ * this from the beginning of htab. The output stack uses the rest of
+ * htab, and contains characters. There is plenty of room for any possible
+ * stack (stack used to be 8000 characters).
+ */
-/*
- * To save much memory, we overlay the table used by compress() with those
- * used by decompress(). The tab_prefix table is the same size and type
- * as the codetab. The tab_suffix table needs 2**GIFBITS characters. We
- * get this from the beginning of htab. The output stack uses the rest
- * of htab, and contains characters. There is plenty of room for any
- * possible stack (stack used to be 8000 characters).
- */
+ int free_ent; /* first unused entry */
- int free_ent; /* first unused entry */
+ /*
+ * block compression parameters -- after all codes are used up,
+ * and compression rate changes, start over.
+ */
-/*
- * block compression parameters -- after all codes are used up,
- * and compression rate changes, start over.
- */
int clear_flg;
int offset;
- unsigned int in_count; /* length of input */
- unsigned int out_count; /* # of codes output (for debugging) */
+ unsigned int in_count; /* length of input */
+ unsigned int out_count; /* # of codes output (for debugging) */
-/*
- * compress stdin to stdout
- *
- * Algorithm: use open addressing double hashing (no chaining) on the
- * prefix code / next character combination. We do a variant of Knuth's
- * algorithm D (vol. 3, sec. 6.4) along with G. Knott's relatively-prime
- * secondary probe. Here, the modular division first probe is gives way
- * to a faster exclusive-or manipulation. Also do block compression with
- * an adaptive reset, whereby the code table is cleared when the compression
- * ratio decreases, but after the table fills. The variable-length output
- * codes are re-sized at this point, and a special CLEAR code is generated
- * for the decompressor. Late addition: construct the table according to
- * file size for noticeable speed improvement on small files. Please direct
- * questions about this implementation to ames!jaw.
- */
+ /*
+ * compress stdin to stdout
+ *
+ * Algorithm: use open addressing double hashing (no chaining) on the
+ * prefix code / next character combination. We do a variant of Knuth's
+ * algorithm D (vol. 3, sec. 6.4) along with G. Knott's relatively-prime
+ * secondary probe. Here, the modular division first probe is gives way to
+ * a faster exclusive-or manipulation. Also do block compression with an
+ * adaptive reset, whereby the code table is cleared when the compression
+ * ratio decreases, but after the table fills. The variable-length output
+ * codes are re-sized at this point, and a special CLEAR code is generated
+ * for the decompressor. Late addition: construct the table according to
+ * file size for noticeable speed improvement on small files. Please
+ * direct questions about this implementation to ames!jaw.
+ */
int g_init_bits;
Tcl_Channel g_outfile;
@@ -1807,34 +1807,36 @@ typedef struct {
int EOFCode;
unsigned long cur_accum;
- int cur_bits;
+ int cur_bits;
+
+ /*
+ * Number of characters so far in this 'packet'
+ */
-/*
- * Number of characters so far in this 'packet'
- */
int a_count;
-/*
- * Define the storage for the packet accumulator
- */
+ /*
+ * Define the storage for the packet accumulator
+ */
+
unsigned char accum[256];
} GIFState_t;
-static void output _ANSI_ARGS_((GIFState_t *statePtr, long code));
-static void cl_block _ANSI_ARGS_((GIFState_t *statePtr));
-static void cl_hash _ANSI_ARGS_((GIFState_t *statePtr, int hsize));
-static void char_init _ANSI_ARGS_((GIFState_t *statePtr));
-static void char_out _ANSI_ARGS_((GIFState_t *statePtr, int c));
-static void flush_char _ANSI_ARGS_((GIFState_t *statePtr));
-
+static void output(GIFState_t *statePtr, long code);
+static void cl_block(GIFState_t *statePtr);
+static void cl_hash(GIFState_t *statePtr, int hsize);
+static void char_init(GIFState_t *statePtr);
+static void char_out(GIFState_t *statePtr, int c);
+static void flush_char(GIFState_t *statePtr);
static void compress(int initBits, Tcl_Channel handle,
ifunptr readValue, GifWriterState *statePtr);
-
-static void compress(init_bits, handle, readValue, statePtr)
- int init_bits;
- Tcl_Channel handle;
- ifunptr readValue;
- GifWriterState *statePtr;
+
+static void
+compress(
+ int init_bits,
+ Tcl_Channel handle,
+ ifunptr readValue,
+ GifWriterState *statePtr)
{
register long fcode;
register long i = 0;
@@ -1846,16 +1848,19 @@ static void compress(init_bits, handle, readValue, statePtr)
GIFState_t state;
memset(&state, 0, sizeof(state));
+
/*
* Set up the globals: g_init_bits - initial number of bits
- * g_outfile - pointer to output file
+ * g_outfile - pointer to output file
*/
+
state.g_init_bits = init_bits;
state.g_outfile = handle;
/*
- * Set up the necessary values
+ * Set up the necessary values.
*/
+
state.offset = 0;
state.hsize = HSIZE;
state.out_count = 0;
@@ -1872,95 +1877,111 @@ static void compress(init_bits, handle, readValue, statePtr)
ent = readValue(statePtr);
hshift = 0;
- for ( fcode = (long) state.hsize; fcode < 65536L; fcode *= 2L )
- hshift++;
- hshift = 8 - hshift; /* set hash code range bound */
+ for (fcode = (long) state.hsize; fcode < 65536L; fcode *= 2L) {
+ hshift++;
+ }
+ hshift = 8 - hshift; /* set hash code range bound */
hsize_reg = state.hsize;
- cl_hash(&state, (int) hsize_reg); /* clear hash table */
+ cl_hash(&state, (int) hsize_reg); /* clear hash table */
- output(&state, (long)state.ClearCode);
+ output(&state, (long) state.ClearCode);
#ifdef SIGNED_COMPARE_SLOW
- while ( (c = readValue(statePtr) ) != (unsigned) EOF ) {
+ while ((c = readValue(statePtr)) != (unsigned) EOF)
#else
- while ( (c = readValue(statePtr)) != EOF ) {
+ while ((c = readValue(statePtr)) != EOF)
#endif
+ {
+ state.in_count++;
+
+ fcode = (long) (((long) c << GIFBITS) + ent);
+ i = (((long)c << hshift) ^ ent); /* xor hashing */
+
+ if (state.htab[i] == fcode) {
+ ent = state.codetab[i];
+ continue;
+ } else if ((long) state.htab[i] < 0) { /* empty slot */
+ goto nomatch;
+ }
+
+ disp = hsize_reg - i; /* secondary hash (after G.
+ * Knott) */
+ if (i == 0) {
+ disp = 1;
+ }
+
+ probe:
+ if ((i -= disp) < 0) {
+ i += hsize_reg;
+ }
- state.in_count++;
-
- fcode = (long) (((long) c << GIFBITS) + ent);
- i = (((long)c << hshift) ^ ent); /* xor hashing */
-
- if (state.htab[i] == fcode) {
- ent = state.codetab[i];
- continue;
- } else if ( (long) state.htab[i] < 0 ) /* empty slot */
- goto nomatch;
- disp = hsize_reg - i; /* secondary hash (after G. Knott) */
- if ( i == 0 )
- disp = 1;
-probe:
- if ( (i -= disp) < 0 )
- i += hsize_reg;
-
- if (state.htab[i] == fcode) {
- ent = state.codetab[i];
- continue;
- }
- if ( (long) state.htab[i] > 0 )
- goto probe;
-nomatch:
- output (&state, (long) ent);
- state.out_count++;
- ent = c;
+ if (state.htab[i] == fcode) {
+ ent = state.codetab[i];
+ continue;
+ }
+ if ((long) state.htab[i] > 0) {
+ goto probe;
+ }
+
+ nomatch:
+ output(&state, (long) ent);
+ state.out_count++;
+ ent = c;
#ifdef SIGNED_COMPARE_SLOW
- if ( (unsigned) free_ent < (unsigned) ((long)1 << GIFBITS)) {
+ if ((unsigned) free_ent < (unsigned) ((long)1 << GIFBITS))
#else
- if (state.free_ent < ((long)1 << GIFBITS)) {
+ if (state.free_ent < ((long)1 << GIFBITS))
#endif
- state.codetab[i] = state.free_ent++; /* code -> hashtable */
- state.htab[i] = fcode;
- } else
- cl_block(&state);
+ {
+ state.codetab[i] = state.free_ent++; /* code -> hashtable */
+ state.htab[i] = fcode;
+ } else {
+ cl_block(&state);
+ }
}
+
/*
* Put out the final code.
*/
+
output(&state, (long)ent);
state.out_count++;
output(&state, (long) state.EOFCode);
return;
}
-
+
/*****************************************************************
* TAG( output )
*
* Output the given code.
* Inputs:
- * code: A n_bits-bit integer. If == -1, then EOF. This assumes
- * that n_bits =< (long) wordsize - 1.
+ * code: A n_bits-bit integer. If == -1, then EOF. This assumes that
+ * n_bits =< (long) wordsize - 1.
* Outputs:
- * Outputs code to the file.
+ * Outputs code to the file.
* Assumptions:
- * Chars are 8 bits long.
+ * Chars are 8 bits long.
* Algorithm:
- * Maintain a GIFBITS character long buffer (so that 8 codes will
- * fit in it exactly). Use the VAX insv instruction to insert each
+ * Maintain a GIFBITS character long buffer (so that 8 codes will
+ * fit in it exactly). Use the VAX insv instruction to insert each
* code in turn. When the buffer fills up empty it and start over.
*/
static const
-unsigned long masks[] = { 0x0000, 0x0001, 0x0003, 0x0007, 0x000F,
- 0x001F, 0x003F, 0x007F, 0x00FF,
- 0x01FF, 0x03FF, 0x07FF, 0x0FFF,
- 0x1FFF, 0x3FFF, 0x7FFF, 0xFFFF };
+unsigned long masks[] = {
+ 0x0000,
+ 0x0001, 0x0003, 0x0007, 0x000F,
+ 0x001F, 0x003F, 0x007F, 0x00FF,
+ 0x01FF, 0x03FF, 0x07FF, 0x0FFF,
+ 0x1FFF, 0x3FFF, 0x7FFF, 0xFFFF
+};
static void
-output(statePtr, code)
- GIFState_t *statePtr;
- long code;
+output(
+ GIFState_t *statePtr,
+ long code)
{
statePtr->cur_accum &= masks[statePtr->cur_bits];
@@ -1973,7 +1994,7 @@ output(statePtr, code)
statePtr->cur_bits += statePtr->n_bits;
while (statePtr->cur_bits >= 8 ) {
- char_out(statePtr, (unsigned int)(statePtr->cur_accum & 0xff));
+ char_out(statePtr, (unsigned) (statePtr->cur_accum & 0xff));
statePtr->cur_accum >>= 8;
statePtr->cur_bits -= 8;
}
@@ -1985,7 +2006,8 @@ output(statePtr, code)
if ((statePtr->free_ent > statePtr->maxcode)|| statePtr->clear_flg ) {
if (statePtr->clear_flg) {
- statePtr->maxcode = MAXCODE(statePtr->n_bits = statePtr->g_init_bits);
+ statePtr->maxcode = MAXCODE(
+ statePtr->n_bits = statePtr->g_init_bits);
statePtr->clear_flg = 0;
} else {
statePtr->n_bits++;
@@ -2001,41 +2023,42 @@ output(statePtr, code)
/*
* At EOF, write the rest of the buffer.
*/
- while (statePtr->cur_bits > 0) {
- char_out(statePtr, (unsigned int)(statePtr->cur_accum & 0xff));
+
+ while (statePtr->cur_bits > 0) {
+ char_out(statePtr, (unsigned) (statePtr->cur_accum & 0xff));
statePtr->cur_accum >>= 8;
statePtr->cur_bits -= 8;
}
flush_char(statePtr);
}
}
-
+
/*
* Clear out the hash table
*/
+
static void
-cl_block(statePtr) /* table clear for block compress */
- GIFState_t *statePtr;
+cl_block( /* table clear for block compress */
+ GIFState_t *statePtr)
{
+ cl_hash(statePtr, (int) statePtr->hsize);
+ statePtr->free_ent = statePtr->ClearCode + 2;
+ statePtr->clear_flg = 1;
- cl_hash (statePtr, (int) statePtr->hsize);
- statePtr->free_ent = statePtr->ClearCode + 2;
- statePtr->clear_flg = 1;
-
- output(statePtr, (long) statePtr->ClearCode);
+ output(statePtr, (long) statePtr->ClearCode);
}
-
+
static void
-cl_hash(statePtr, hsize) /* reset code table */
- GIFState_t *statePtr;
- int hsize;
+cl_hash( /* reset code table */
+ GIFState_t *statePtr,
+ int hsize)
{
- register int *htab_p = statePtr->htab+hsize;
+ register int *htab_p = statePtr->htab + hsize;
register long i;
register long m1 = -1;
i = hsize - 16;
- do { /* might use Sys V memset(3) here */
+ do { /* might use Sys V memset(3) here */
*(htab_p-16) = m1;
*(htab_p-15) = m1;
*(htab_p-14) = m1;
@@ -2059,53 +2082,59 @@ cl_hash(statePtr, hsize) /* reset code table */
*--htab_p = m1;
}
}
-
-
-/******************************************************************************
+
+/*
+ *****************************************************************************
*
* GIF Specific routines
*
- ******************************************************************************/
+ *****************************************************************************
+ */
/*
* Set up the 'byte output' routine
*/
+
static void
-char_init(statePtr)
- GIFState_t *statePtr;
+char_init(
+ GIFState_t *statePtr)
{
statePtr->a_count = 0;
statePtr->cur_accum = 0;
statePtr->cur_bits = 0;
}
-
+
/*
* Add a character to the end of the current packet, and if it is 254
* characters, flush the packet to disk.
*/
+
static void
-char_out(statePtr, c)
- GIFState_t *statePtr;
- int c;
+char_out(
+ GIFState_t *statePtr,
+ int c)
{
statePtr->accum[statePtr->a_count++] = c;
if (statePtr->a_count >= 254) {
flush_char(statePtr);
}
}
-
+
/*
* Flush the packet to disk, and reset the accumulator
*/
+
static void
-flush_char(statePtr)
- GIFState_t *statePtr;
+flush_char(
+ GIFState_t *statePtr)
{
unsigned char c;
+
if (statePtr->a_count > 0) {
c = statePtr->a_count;
- Tcl_Write(statePtr->g_outfile, (CONST char *) &c, 1);
- Tcl_Write(statePtr->g_outfile, (CONST char *) statePtr->accum, statePtr->a_count);
+ Tcl_Write(statePtr->g_outfile, (const char *) &c, 1);
+ Tcl_Write(statePtr->g_outfile, (const char *) statePtr->accum,
+ statePtr->a_count);
statePtr->a_count = 0;
}
}
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