working gif support

3 files changed, 32 insertions, 225 deletions

diff --git a/Makefile b/Makefile
index 03f7b66..d773d53 100644
--- a/Makefile
+++ b/Makefile
@@ -7,7 +7,7 @@ OBJFILES := $(SRCFILES:%.c=%.o)
 DEPFILES := $(OBJFILES:%.o=%.d)
 CLEANFILES := $(CLEANFILES) $(DEPFILES) $(OBJFILES) meh
 CFLAGS := $(CFLAGS) -O3 -Wall -g -ggdb
-LIBS := -lX11 -ljpeg -lpng
+LIBS := -lX11 -ljpeg -lpng -lgif
 
 meh: $(OBJFILES)
 	$(CC) -o $@ $(OBJFILES) $(LIBS)
diff --git a/src/gif.c b/src/gif.c
index 676fd98..93a4517 100644
--- a/src/gif.c
+++ b/src/gif.c
@@ -4,232 +4,42 @@
 
 #include <assert.h>
 
-#include "meh.h"
-
-#define GIF87a 0
-#define GIF89a 1
+#include <gif_lib.h>
 
-#define MAX_CODES 4096
+#include "meh.h"
 
-unsigned char *loadgif(FILE *infile, int *bufwidth, int *bufheight){
-	int version;
-	unsigned char *palette;
-	int pallen;
-	unsigned char *buf = NULL;
-	unsigned int bpp;
 
-	{
-		/* Read header*/
-		unsigned char packed;
-		unsigned char header[13];
-		
-		if(fread(header, 1, 13, infile) != 13)
-			return NULL;
-		if(!memcmp("GIF89a", header, 6))
-			version = GIF89a;
-		else if(!memcmp("GIF87a", header, 6))
-			version = GIF87a;
-		else
-			return NULL;
-		
-		*bufwidth = header[6] | header[7] << 8;
-		*bufheight = header[8] | header[9] << 8;
-		packed = header[10];
-		bpp = (packed & 7) + 1;
+unsigned char *loadgif(FILE *f, int *bufwidth, int *bufheight){
+	GifFileType *gif;
+	SavedImage *img;
+	GifColorType *colormap;
 
-		/* Read colormap */
-		if(packed & 0x80){
-			printf("Reading palette\n");
-			pallen = 1 << bpp;
-			printf("pallen: %i\n", pallen);
-			palette = malloc(3 * pallen);
-			fread(palette, 1, 3 * pallen, infile);
-		}
+	unsigned char *buf;
+	if(!(gif = DGifOpenFileHandle(fileno(f)))){
+		return NULL;
 	}
-
-	{
-		int blocktype;
-		while((blocktype = fgetc(infile)) != EOF){
-			if(blocktype == ';'){
-				printf("end of file\n");
-				break;
-			}else if(blocktype == '!'){
-				int bytecount, fncode;
-				if((fncode = fgetc(infile)) == EOF)
-					return NULL;
-				while(1){
-					bytecount = fgetc(infile);
-					printf("Skipping extblock 0x%x\n", fncode);
-					if(bytecount == EOF)
-						return NULL;
-					else if(bytecount > 0)
-						fseek(infile, bytecount, SEEK_CUR);
-					else
-						break;
-				}
-			}else if(blocktype == ','){
-				int imagex, imagey, imagew, imageh;
-				unsigned char imagedesc[9];
-				if(fread(imagedesc, 1, 9, infile) != 9)
-					return NULL;
-				if(imagedesc[8] & 0x80){
-					printf("ERROR: local palettes not supported\n");
-					return NULL;
-				}
-				if(imagedesc[8] & 0x40){
-					printf("ERROR: interlaced images\n");
-					return NULL;
-				}
-
-				imagex = imagedesc[0] | imagedesc[1] << 8;
-				imagey = imagedesc[2] | imagedesc[3] << 8;
-				imagew = imagedesc[4] | imagedesc[5] << 8;
-				imageh = imagedesc[6] | imagedesc[7] << 8;
-
-				if(imagex != 0 || imagey != 0 || imagew != *bufwidth || imageh != *bufheight){
-					printf("%ix%i %ix%i\n", imagex, imagey, imagew, imageh);
-					printf("TODO: allow this sort of thing\n");
-					return NULL;
-				}
-
-				buf = malloc((*bufwidth) * (*bufheight) * 3);
-				memset(buf, 0, (*bufwidth) * (*bufheight) * 3);
-
-				{
-					unsigned int initcodesize, curcodesize;
-					unsigned int clearcode, endcode, newcode;
-					int bytesleft = 0;
-					int i = 0;
-
-					/* Get code size */
-					initcodesize = fgetc(infile);
-					if(initcodesize < 1 || initcodesize > 9){
-						printf("bad code size %i\n", initcodesize);
-						return NULL;
-					}
-					curcodesize = initcodesize + 1;
-					clearcode = 1 << initcodesize;
-					endcode = clearcode + 1;
-					newcode = endcode + 1;
-
-					int count = 0;
-					int byte0 = -1, byte1 = -1, byteshift = 0;
-					unsigned int suffix[MAX_CODES * 3];
-					unsigned int prefix[MAX_CODES];
-					int length[MAX_CODES];
-
-					goto clear;
-					for(;;){
-						for(;;){
-							count++;
-							int a, b, c;
-							int code;
-							/* get code */
-							
-							while(byte1 == -1){
-								if(!bytesleft){
-									bytesleft = fgetc(infile);
-									if(bytesleft < 0){
-										printf("unexpected EOF (0)\n");
-										return NULL;
-									}else if(bytesleft == 0)
-										break;
-								}
-								if((byte1 = fgetc(infile)) == EOF){
-									printf("unexpected EOF (1)\n");
-									return NULL;
-								}
-								if(byte0 == -1){
-									byte0 = byte1;
-									byte1 = -1;
-								}
-								bytesleft--;
-							}
-							code = ((byte0 | (byte1 << 8)) >> byteshift) & ((1 << curcodesize) - 1);
-							byteshift += curcodesize;
-							while(byteshift >= 8){
-								byte0 = byte1;
-								byte1 = -1;
-								byteshift -= 8;
-							}
-
-							if(code == clearcode){
-								if(i){
-									buf[(i-1)*3] = 0xff;
-									buf[(i-1)*3+1] = 0;
-									buf[(i-1)*3+2] = 0;
-								}
-clear:
-								printf("%i. clear\n", count);
-								curcodesize = initcodesize + 1;
-								newcode = endcode; /* endcode is also used as a sentinel */
-								for(a = 0; a < clearcode; a++){
-									length[a] = 0;
-									prefix[a] = 0;
-
-									suffix[a*3] = palette[a*3];
-									suffix[a*3+1] = palette[a*3+1];
-									suffix[a*3+2] = palette[a*3+2];
-								}
-								
-							}else if(code == endcode){
-								printf("%i. endcode\n", count);
-								return buf;
-							}else{
-								assert(newcode < MAX_CODES);
-								if(code <= newcode){
-									prefix[newcode+1] = i;
-									length[newcode+1] = length[code] + 1;
-									for(a = prefix[code]; a < prefix[code] + length[code]; a++){
-										buf[i*3] = buf[a*3];
-										buf[i*3+1] = buf[a*3+1];
-										buf[i*3+2] = buf[a*3+2];
-										i++;
-									}
-									buf[i*3] = suffix[code*3];
-									buf[i*3+1] = suffix[code*3+1];
-									buf[i*3+2] = suffix[code*3+1];
-									i++;
-
-									suffix[newcode*3 + 3] = suffix[newcode*3] = buf[prefix[newcode+1] * 3];
-									suffix[newcode*3 + 4] = suffix[newcode*3 + 1] = buf[prefix[newcode+1] * 3 + 1];
-									suffix[newcode*3 + 5] = suffix[newcode*3 + 2] = buf[prefix[newcode+1] * 3 + 2];
-								}else{
-									printf("code > newcode (%x > %x)\n", code, newcode);
-									return buf;
-									//exit(1);
-								}
-								
-								newcode++;
-								if(newcode >= 1 << curcodesize){
-									buf[(i-1)*3] = 0xff;
-									buf[(i-1)*3+1] = 0;
-									buf[(i-1)*3+2] = 0xff;
-									curcodesize++;
-									printf("curcodesize = %i\n", curcodesize);
-									if(curcodesize == 11){
-										curcodesize = 11;
-									}
-								}
-							}
-						}
-					}
-					
-					/*for(i = 0; i < (*bufwidth) * (*bufheight); i++){
-					}*/
-					printf("good end\n");
-					return buf;
-				}
-
-				break;
-			}else{
-				printf("Unknown block type %i\n", blocktype);
-				return NULL;
-			}
-		}
+	if(DGifSlurp(gif) == GIF_ERROR){
+		return NULL;
 	}
-
-	printf("end\n");
-	return NULL;
+	img = &gif->SavedImages[0];
+	*bufwidth = img->ImageDesc.Width;
+	*bufheight = img->ImageDesc.Height;
+	buf = malloc(img->ImageDesc.Width * img->ImageDesc.Height * 3);
+
+	if(img->ImageDesc.ColorMap)
+		colormap = img->ImageDesc.ColorMap->Colors;
+	else if(gif->SColorMap)
+		colormap = gif->SColorMap->Colors;
+	else
+		return NULL;
+
+	int i, j = 0;
+	for(i = 0; i < img->ImageDesc.Width * img->ImageDesc.Height; i++){
+		unsigned char idx = img->RasterBits[i];
+		buf[j++] = colormap[idx].Red;
+		buf[j++] = colormap[idx].Green;
+		buf[j++] = colormap[idx].Blue;
+	}
+	return buf;
 }
 
diff --git a/src/main.c b/src/main.c
index 41b09ce..c116fab 100644
--- a/src/main.c
+++ b/src/main.c
@@ -206,7 +206,6 @@ void run(struct imagenode *image){
 				case MapNotify:
 					break;
 				case ConfigureNotify:
-					printf("ConfigureNotify\n");
 					if(width != event.xconfigure.width || height != event.xconfigure.height){
 						if(img){
 							free(img->data);
@@ -273,7 +272,6 @@ void run(struct imagenode *image){
 					free(tmp);
 				}
 				setaspect(bufwidth, bufheight);
-				printf("setaspect\n");
 			}
 			if(!img){
 				if(width * bufheight > height * bufwidth){
@@ -295,7 +293,6 @@ void run(struct imagenode *image){
 					yoffset = 0;
 				}
 				img = create_image_from_buffer(buf, imagewidth, imageheight, bufwidth, bufheight);
-				printf("img\n");
 				assert(img);
 			}
 			XFillRectangle(display, window, gc, 0, 0, fillw, fillh);