auto import from //depot/cupcake/@135843

1 files changed, 443 insertions, 0 deletions

diff --git a/gifalloc.c b/gifalloc.c
new file mode 100644
index 0000000..79d2332
--- /dev/null
+++ b/gifalloc.c
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+/*****************************************************************************
+ *   "Gif-Lib" - Yet another gif library.                     
+ *                                         
+ * Written by:  Gershon Elber                Ver 0.1, Jun. 1989   
+ * Extensively hacked by: Eric S. Raymond        Ver 1.?, Sep 1992    
+ *****************************************************************************
+ * GIF construction tools                              
+ *****************************************************************************
+ * History:                                     
+ * 15 Sep 92 - Version 1.0 by Eric Raymond.                     
+ ****************************************************************************/
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include "gif_lib.h"
+
+#define MAX(x, y)    (((x) > (y)) ? (x) : (y))
+
+/******************************************************************************
+ * Miscellaneous utility functions                          
+ *****************************************************************************/
+
+/* return smallest bitfield size n will fit in */
+int
+BitSize(int n) {
+    
+    register int i;
+
+    for (i = 1; i <= 8; i++)
+        if ((1 << i) >= n)
+            break;
+    return (i);
+}
+
+/******************************************************************************
+ * Color map object functions                              
+ *****************************************************************************/
+
+/*
+ * Allocate a color map of given size; initialize with contents of
+ * ColorMap if that pointer is non-NULL.
+ */
+ColorMapObject *
+MakeMapObject(int ColorCount,
+              const GifColorType * ColorMap) {
+    
+    ColorMapObject *Object;
+
+    /*** FIXME: Our ColorCount has to be a power of two.  Is it necessary to
+     * make the user know that or should we automatically round up instead? */
+    if (ColorCount != (1 << BitSize(ColorCount))) {
+        return ((ColorMapObject *) NULL);
+    }
+    
+    Object = (ColorMapObject *)malloc(sizeof(ColorMapObject));
+    if (Object == (ColorMapObject *) NULL) {
+        return ((ColorMapObject *) NULL);
+    }
+
+    Object->Colors = (GifColorType *)calloc(ColorCount, sizeof(GifColorType));
+    if (Object->Colors == (GifColorType *) NULL) {
+        return ((ColorMapObject *) NULL);
+    }
+
+    Object->ColorCount = ColorCount;
+    Object->BitsPerPixel = BitSize(ColorCount);
+
+    if (ColorMap) {
+        memcpy((char *)Object->Colors,
+               (char *)ColorMap, ColorCount * sizeof(GifColorType));
+    }
+
+    return (Object);
+}
+
+/*
+ * Free a color map object
+ */
+void
+FreeMapObject(ColorMapObject * Object) {
+
+    if (Object != NULL) {
+        free(Object->Colors);
+        free(Object);
+        /*** FIXME:
+         * When we are willing to break API we need to make this function
+         * FreeMapObject(ColorMapObject **Object)
+         * and do this assignment to NULL here:
+         * *Object = NULL;
+         */
+    }
+}
+
+#ifdef DEBUG
+void
+DumpColorMap(ColorMapObject * Object,
+             FILE * fp) {
+
+    if (Object) {
+        int i, j, Len = Object->ColorCount;
+
+        for (i = 0; i < Len; i += 4) {
+            for (j = 0; j < 4 && j < Len; j++) {
+                fprintf(fp, "%3d: %02x %02x %02x   ", i + j,
+                        Object->Colors[i + j].Red,
+                        Object->Colors[i + j].Green,
+                        Object->Colors[i + j].Blue);
+            }
+            fprintf(fp, "\n");
+        }
+    }
+}
+#endif /* DEBUG */
+
+/*
+ * Compute the union of two given color maps and return it.  If result can't 
+ * fit into 256 colors, NULL is returned, the allocated union otherwise.
+ * ColorIn1 is copied as is to ColorUnion, while colors from ColorIn2 are
+ * copied iff they didn't exist before.  ColorTransIn2 maps the old
+ * ColorIn2 into ColorUnion color map table.
+ */
+ColorMapObject *
+UnionColorMap(const ColorMapObject * ColorIn1,
+              const ColorMapObject * ColorIn2,
+              GifPixelType ColorTransIn2[]) {
+
+    int i, j, CrntSlot, RoundUpTo, NewBitSize;
+    ColorMapObject *ColorUnion;
+
+    /* 
+     * Allocate table which will hold the result for sure.
+     */
+    ColorUnion = MakeMapObject(MAX(ColorIn1->ColorCount,
+                               ColorIn2->ColorCount) * 2, NULL);
+
+    if (ColorUnion == NULL)
+        return (NULL);
+
+    /* Copy ColorIn1 to ColorUnionSize; */
+    /*** FIXME: What if there are duplicate entries into the colormap to begin
+     * with? */
+    for (i = 0; i < ColorIn1->ColorCount; i++)
+        ColorUnion->Colors[i] = ColorIn1->Colors[i];
+    CrntSlot = ColorIn1->ColorCount;
+
+    /* 
+     * Potentially obnoxious hack:
+     *
+     * Back CrntSlot down past all contiguous {0, 0, 0} slots at the end
+     * of table 1.  This is very useful if your display is limited to
+     * 16 colors.
+     */
+    while (ColorIn1->Colors[CrntSlot - 1].Red == 0
+           && ColorIn1->Colors[CrntSlot - 1].Green == 0
+           && ColorIn1->Colors[CrntSlot - 1].Blue == 0)
+        CrntSlot--;
+
+    /* Copy ColorIn2 to ColorUnionSize (use old colors if they exist): */
+    for (i = 0; i < ColorIn2->ColorCount && CrntSlot <= 256; i++) {
+        /* Let's see if this color already exists: */
+        /*** FIXME: Will it ever occur that ColorIn2 will contain duplicate
+         * entries?  So we should search from 0 to CrntSlot rather than
+         * ColorIn1->ColorCount?
+         */
+        for (j = 0; j < ColorIn1->ColorCount; j++)
+            if (memcmp (&ColorIn1->Colors[j], &ColorIn2->Colors[i], 
+                        sizeof(GifColorType)) == 0)
+                break;
+
+        if (j < ColorIn1->ColorCount)
+            ColorTransIn2[i] = j;    /* color exists in Color1 */
+        else {
+            /* Color is new - copy it to a new slot: */
+            ColorUnion->Colors[CrntSlot] = ColorIn2->Colors[i];
+            ColorTransIn2[i] = CrntSlot++;
+        }
+    }
+
+    if (CrntSlot > 256) {
+        FreeMapObject(ColorUnion);
+        return ((ColorMapObject *) NULL);
+    }
+
+    NewBitSize = BitSize(CrntSlot);
+    RoundUpTo = (1 << NewBitSize);
+
+    if (RoundUpTo != ColorUnion->ColorCount) {
+        register GifColorType *Map = ColorUnion->Colors;
+
+        /* 
+         * Zero out slots up to next power of 2.
+         * We know these slots exist because of the way ColorUnion's
+         * start dimension was computed.
+         */
+        for (j = CrntSlot; j < RoundUpTo; j++)
+            Map[j].Red = Map[j].Green = Map[j].Blue = 0;
+
+        /* perhaps we can shrink the map? */
+        if (RoundUpTo < ColorUnion->ColorCount)
+            ColorUnion->Colors = (GifColorType *)realloc(Map,
+                                 sizeof(GifColorType) * RoundUpTo);
+    }
+
+    ColorUnion->ColorCount = RoundUpTo;
+    ColorUnion->BitsPerPixel = NewBitSize;
+
+    return (ColorUnion);
+}
+
+/*
+ * Apply a given color translation to the raster bits of an image
+ */
+void
+ApplyTranslation(SavedImage * Image,
+                 GifPixelType Translation[]) {
+
+    register int i;
+    register int RasterSize = Image->ImageDesc.Height * Image->ImageDesc.Width;
+
+    for (i = 0; i < RasterSize; i++)
+        Image->RasterBits[i] = Translation[Image->RasterBits[i]];
+}
+
+/******************************************************************************
+ * Extension record functions                              
+ *****************************************************************************/
+
+void
+MakeExtension(SavedImage * New,
+              int Function) {
+
+    New->Function = Function;
+    /*** FIXME:
+     * Someday we might have to deal with multiple extensions.
+     * ??? Was this a note from Gershon or from me?  Does the multiple
+     * extension blocks solve this or do we need multiple Functions?  Or is
+     * this an obsolete function?  (People should use AddExtensionBlock
+     * instead?)
+     * Looks like AddExtensionBlock needs to take the int Function argument
+     * then it can take the place of this function.  Right now people have to
+     * use both.  Fix AddExtensionBlock and add this to the deprecation list.
+     */
+}
+
+int
+AddExtensionBlock(SavedImage * New,
+                  int Len,
+                  unsigned char ExtData[]) {
+
+    ExtensionBlock *ep;
+
+    if (New->ExtensionBlocks == NULL)
+        New->ExtensionBlocks=(ExtensionBlock *)malloc(sizeof(ExtensionBlock));
+    else
+        New->ExtensionBlocks = (ExtensionBlock *)realloc(New->ExtensionBlocks,
+                                      sizeof(ExtensionBlock) *
+                                      (New->ExtensionBlockCount + 1));
+
+    if (New->ExtensionBlocks == NULL)
+        return (GIF_ERROR);
+
+    ep = &New->ExtensionBlocks[New->ExtensionBlockCount++];
+
+    ep->ByteCount=Len;
+    ep->Bytes = (char *)malloc(ep->ByteCount);
+    if (ep->Bytes == NULL)
+        return (GIF_ERROR);
+
+    if (ExtData) {
+        memcpy(ep->Bytes, ExtData, Len);
+        ep->Function = New->Function;
+    }
+
+    return (GIF_OK);
+}
+
+void
+FreeExtension(SavedImage * Image)
+{
+    ExtensionBlock *ep;
+
+    if ((Image == NULL) || (Image->ExtensionBlocks == NULL)) {
+        return;
+    }
+    for (ep = Image->ExtensionBlocks;
+         ep < (Image->ExtensionBlocks + Image->ExtensionBlockCount); ep++)
+        (void)free((char *)ep->Bytes);
+    free((char *)Image->ExtensionBlocks);
+    Image->ExtensionBlocks = NULL;
+}
+
+/******************************************************************************
+ * Image block allocation functions                          
+******************************************************************************/
+
+/* Private Function:
+ * Frees the last image in the GifFile->SavedImages array
+ */
+void
+FreeLastSavedImage(GifFileType *GifFile) {
+
+    SavedImage *sp;
+    
+    if ((GifFile == NULL) || (GifFile->SavedImages == NULL))
+        return;
+
+    /* Remove one SavedImage from the GifFile */
+    GifFile->ImageCount--;
+    sp = &GifFile->SavedImages[GifFile->ImageCount];
+
+    /* Deallocate its Colormap */
+    if (sp->ImageDesc.ColorMap) {
+        FreeMapObject(sp->ImageDesc.ColorMap);
+        sp->ImageDesc.ColorMap = NULL;
+    }
+
+    /* Deallocate the image data */
+    if (sp->RasterBits)
+        free((char *)sp->RasterBits);
+
+    /* Deallocate any extensions */
+    if (sp->ExtensionBlocks)
+        FreeExtension(sp);
+
+    /*** FIXME: We could realloc the GifFile->SavedImages structure but is
+     * there a point to it? Saves some memory but we'd have to do it every
+     * time.  If this is used in FreeSavedImages then it would be inefficient
+     * (The whole array is going to be deallocated.)  If we just use it when
+     * we want to free the last Image it's convenient to do it here.
+     */
+}
+
+/*
+ * Append an image block to the SavedImages array  
+ */
+SavedImage *
+MakeSavedImage(GifFileType * GifFile,
+               const SavedImage * CopyFrom) {
+
+    SavedImage *sp;
+
+    if (GifFile->SavedImages == NULL)
+        GifFile->SavedImages = (SavedImage *)malloc(sizeof(SavedImage));
+    else
+        GifFile->SavedImages = (SavedImage *)realloc(GifFile->SavedImages,
+                               sizeof(SavedImage) * (GifFile->ImageCount + 1));
+
+    if (GifFile->SavedImages == NULL)
+        return ((SavedImage *)NULL);
+    else {
+        sp = &GifFile->SavedImages[GifFile->ImageCount++];
+        memset((char *)sp, '\0', sizeof(SavedImage));
+
+        if (CopyFrom) {
+            memcpy((char *)sp, CopyFrom, sizeof(SavedImage));
+
+            /* 
+             * Make our own allocated copies of the heap fields in the
+             * copied record.  This guards against potential aliasing
+             * problems.
+             */
+
+            /* first, the local color map */
+            if (sp->ImageDesc.ColorMap) {
+                sp->ImageDesc.ColorMap = MakeMapObject(
+                                         CopyFrom->ImageDesc.ColorMap->ColorCount,
+                                         CopyFrom->ImageDesc.ColorMap->Colors);
+                if (sp->ImageDesc.ColorMap == NULL) {
+                    FreeLastSavedImage(GifFile);
+                    return (SavedImage *)(NULL);
+                }
+            }
+
+            /* next, the raster */
+            sp->RasterBits = (unsigned char *)malloc(sizeof(GifPixelType) *
+                                                   CopyFrom->ImageDesc.Height *
+                                                   CopyFrom->ImageDesc.Width);
+            if (sp->RasterBits == NULL) {
+                FreeLastSavedImage(GifFile);
+                return (SavedImage *)(NULL);
+            }
+            memcpy(sp->RasterBits, CopyFrom->RasterBits,
+                   sizeof(GifPixelType) * CopyFrom->ImageDesc.Height *
+                   CopyFrom->ImageDesc.Width);
+
+            /* finally, the extension blocks */
+            if (sp->ExtensionBlocks) {
+                sp->ExtensionBlocks = (ExtensionBlock *)malloc(
+                                      sizeof(ExtensionBlock) *
+                                      CopyFrom->ExtensionBlockCount);
+                if (sp->ExtensionBlocks == NULL) {
+                    FreeLastSavedImage(GifFile);
+                    return (SavedImage *)(NULL);
+                }
+                memcpy(sp->ExtensionBlocks, CopyFrom->ExtensionBlocks,
+                       sizeof(ExtensionBlock) * CopyFrom->ExtensionBlockCount);
+
+                /* 
+                 * For the moment, the actual blocks can take their
+                 * chances with free().  We'll fix this later. 
+                 *** FIXME: [Better check this out... Toshio]
+                 * 2004 May 27: Looks like this was an ESR note.
+                 * It means the blocks are shallow copied from InFile to
+                 * OutFile.  However, I don't see that in this code....
+                 * Did ESR fix it but never remove this note (And other notes
+                 * in gifspnge?)
+                 */
+            }
+        }
+
+        return (sp);
+    }
+}
+
+void
+FreeSavedImages(GifFileType * GifFile) {
+
+    SavedImage *sp;
+
+    if ((GifFile == NULL) || (GifFile->SavedImages == NULL)) {
+        return;
+    }
+    for (sp = GifFile->SavedImages;
+         sp < GifFile->SavedImages + GifFile->ImageCount; sp++) {
+        if (sp->ImageDesc.ColorMap) {
+            FreeMapObject(sp->ImageDesc.ColorMap);
+            sp->ImageDesc.ColorMap = NULL;
+        }
+
+        if (sp->RasterBits)
+            free((char *)sp->RasterBits);
+
+        if (sp->ExtensionBlocks)
+            FreeExtension(sp);
+    }
+    free((char *)GifFile->SavedImages);
+    GifFile->SavedImages=NULL;
+}