TODO: GIF対応

Makefile

@@ -3,9 +3,9 @@ VERSION=0.1.0
 # Linux、Haiku、かIllumos = /usr、FreeBSDかOpenBSD = /usr/local、NetBSD = /usr/pkg
 PREFIX=/usr
 CC=cc
-FILES=main.c format/png.c format/webp.c
+FILES=main.c format/png.c format/webp.c format/gif.c
 CFLAGS=-Wall -Wextra -g
-LDFLAGS=-lX11 -lpng -lwebp
+LDFLAGS=-lX11 -lpng -lwebp -lgif
 
 all:
 	${CC} ${CFLAGS} -o ${NAME} ${FILES} ${LDFLAGS}

format/gif.c

@@ -0,0 +1,162 @@
+#include "gif.h"
+
+XImage *ximage_from_frame(Display *d, GifFileType *file) {
+  int depth = 32;
+  int width = file->Image.Width;
+  int height = file->Image.Height;
+
+  char *imgdata = malloc(width * height * 4);
+  if (imgdata == NULL) {
+    perror("画像データ向けメモリを割り当てに失敗\n");
+    return NULL;
+  }
+
+  GifPixelType *raster = (GifPixelType *)malloc(width * height * sizeof(GifPixelType));
+  if (!raster) {
+    fprintf(stderr, "メモリ割当に失敗\n");
+    return NULL;
+  }
+
+  for (int i = 0; i < height; ++i) {
+    if (DGifGetLine(file, raster + i * width, width) == GIF_ERROR) {
+      fprintf(stderr, "ラスタースキャンに失敗\n");
+      free(raster);
+      return NULL;
+    }
+  }
+
+  ColorMapObject *cmap = file->Image.ColorMap ? file->Image.ColorMap : file->SColorMap;
+
+  for (int y = 0; y < height; y++) {
+    for (int x = 0; x < width; x++) {
+      GifPixelType px = raster[y * width + x];
+      GifColorType col = cmap->Colors[px];
+
+      // 32ビットARGB形式に交換
+      uint32_t argb = 0xFF << 24 | // 透明
+                 col.Red   << 16 | // 赤
+                 col.Green <<  8 | // 緑
+                 col.Blue;         // 青
+
+      // imgdataに保存
+      ((uint32_t *)imgdata)[y * width + x] = argb;
+    }
+  }
+
+  free(raster);
+
+  // XImageを創作
+  XImage *img = XCreateImage(d, DefaultVisual(d, 0), depth, ZPixmap, 0, imgdata, width, height, 32, 0);
+  if (img == NULL) {
+    fprintf(stderr, "XImageを創作に失敗\n");
+    free(imgdata);
+    return NULL;
+  }
+
+  return img;
+}
+
+GifAnimation* read_gif(Display *d, const char *filename) {
+  GifFileType *file;
+  if ((file = DGifOpenFileName(filename, NULL)) == NULL) {
+    perror("GIFファイルを開けられません。");
+    return NULL;
+  }
+
+  GifAnimation *anime = malloc(sizeof(GifAnimation));
+  if (anime == NULL) {
+    DGifCloseFile(file, NULL);
+    perror("GIFファイルを開けられません。");
+    return NULL;
+  }
+
+  int framecnt = 0; 
+  int ExtCode;
+  GifByteType *Extension;
+  GifRecordType RecordType;
+
+  do {
+    if (DGifGetRecordType(file, &RecordType) == GIF_ERROR) {
+      fprintf(stderr, "GIFエラー\n");
+      break;
+    }
+
+    if (RecordType == IMAGE_DESC_RECORD_TYPE) {
+      framecnt++;
+    }
+  } while (RecordType != TERMINATE_RECORD_TYPE);
+
+  anime->frames = malloc(sizeof(XImage*) * framecnt);
+  anime->delays = malloc(sizeof(int) * framecnt);
+
+  if (anime->frames == NULL || anime->delays == NULL) {
+    fprintf(stderr, "フレームや延長向けメモリを作成に失敗しました。\n");
+    free(anime);
+    DGifCloseFile(file, NULL);
+    return NULL;
+  }
+
+  DGifCloseFile(file, NULL);
+  file = DGifOpenFileName(filename, NULL);
+
+  int i = 0;
+  do {
+    if (DGifGetRecordType(file, &RecordType) == GIF_ERROR) {
+      fprintf(stderr, "GIFエラー\n");
+      break;
+    }
+
+    switch (RecordType) {
+      case IMAGE_DESC_RECORD_TYPE:
+        if (DGifGetImageDesc(file) == GIF_ERROR) {
+          fprintf(stderr, "GIF説明エラー\n");
+          break;
+        }
+
+        XImage *img = ximage_from_frame(d, file);
+        if (img == NULL) {
+          fprintf(stderr, "フレーム %d のXImageを創作に失敗。\n", i);
+          break;
+        }
+
+        anime->frames[i] = img;
+
+        i++;
+        break;
+      case EXTENSION_RECORD_TYPE:
+        if (DGifGetExtension(file, &ExtCode, &Extension) == GIF_ERROR) {
+          fprintf(stderr, "GIF種類エラー\n");
+        }
+
+        if (ExtCode == GRAPHICS_EXT_FUNC_CODE) {
+          int delay = Extension[2] | (Extension[3] << 8);
+          anime->delays[i] = delay;
+        }
+        break;
+      default:
+        break;
+    }
+  } while (RecordType != TERMINATE_RECORD_TYPE);
+
+  if (framecnt == 0) {
+    fprintf(stderr, "GIFフレームを見つけられませんでした。\n");
+    free(anime);
+    DGifCloseFile(file, NULL);
+    return NULL;
+  }
+
+  anime->frames = malloc(sizeof(XImage*) * framecnt);
+  anime->delays = malloc(sizeof(int) * framecnt);
+
+  if (anime->frames == NULL || anime->delays == NULL) {
+    fprintf(stderr, "フレームや延長向けメモリを作成に失敗しました。\n");
+    free(anime->frames);
+    free(anime->delays);
+    free(anime);
+    DGifCloseFile(file, NULL);
+    return NULL;
+  }
+
+  DGifCloseFile(file, NULL);
+  return anime;
+}

format/gif.h

@@ -0,0 +1,28 @@
+#ifndef _GIF_H
+#define _GIF_H
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <X11/Xlib.h>
+#include <gif_lib.h>
+
+typedef struct {
+  XImage **frames;
+  int width;
+  int height;
+  int *delays;
+  int framecnt;
+} GifAnimation;
+
+typedef struct {
+  GifAnimation *anime;
+  int width;
+  int height;
+  XImage **frames;
+  int framecnt;
+} GifWrap;
+
+GifAnimation* read_gif(Display *d, const char *filename);
+
+#endif

main.c

@@ -2,6 +2,7 @@
 #include <stdlib.h>
 #include <string.h>
 #include <errno.h>
+#include <sys/time.h>
 
 #include <X11/Xlib.h>
 #include <X11/Xutil.h>
@@ -9,6 +10,22 @@
 
 #include "format/png.h"
 #include "format/webp.h"
+#include "format/gif.h"
+
+typedef enum {
+  STATIC,
+  ANIME
+} ImgType;
+
+typedef struct {
+  ImgType type;
+  int width;
+  int height;
+  union {
+    XImage *simg;
+    GifWrap *aimg;
+  } imgdata;
+} LoliImg;
 
 int XErrorHandlerd(Display *d, XErrorEvent *event) {
   char error_text[120];
@@ -17,7 +34,7 @@ int XErrorHandlerd(Display *d, XErrorEvent *event) {
   return 0;
 }
 
-XImage* openimg(Display *d, const char *filename) {
+LoliImg* openimg(Display *d, const char *filename) {
   FILE *fp;
   fp = fopen(filename, "rb");
   if (!fp) {
@@ -29,16 +46,54 @@ XImage* openimg(Display *d, const char *filename) {
   fread(buf, 1, 16, fp);
   fclose(fp);
 
+  LoliImg *limg = malloc(sizeof(LoliImg));
+
   if (memcmp(buf, "\x89\x50\x4E\x47\x0D\x0A\x1A\x0A", 8) == 0) { // PNG
-    return read_png(d, filename);
+    limg->type = STATIC;
+    limg->imgdata.simg = read_png(d, filename);
+    limg->width = limg->imgdata.simg->width;
+    limg->height = limg->imgdata.simg->height;
+    return limg;
   } else if (memcmp(buf + 8, "WEBP", 4) == 0) { // WEBP
-    return read_webp(d, filename);
+    limg->type = STATIC;
+    limg->imgdata.simg = read_webp(d, filename);
+    limg->width = limg->imgdata.simg->width;
+    limg->height = limg->imgdata.simg->height;
+    return limg;
+  } else if (memcmp(buf, "GIF", 3) == 0) { // GIF
+    GifWrap *wrap = malloc(sizeof(GifWrap));
+    wrap->anime = read_gif(d, filename);
+    wrap->width = wrap->anime->width;
+    wrap->height = wrap->anime->height;
+    wrap->frames = wrap->anime->frames;
+    wrap->framecnt = wrap->anime->framecnt;
+
+    limg->type = ANIME;
+    limg->imgdata.aimg = wrap;
+    limg->width = wrap->width;
+    limg->height = wrap->height;
+    return limg;
   }
 
+  free(limg);
   fprintf(stderr, "不明なファイル種類。\n");
   return NULL;
 }
 
+void GentleDestroyLoliImage(LoliImg *limg) {
+  if (limg->type == STATIC) {
+    XDestroyImage(limg->imgdata.simg);
+  } else if (limg->type == ANIME) {
+    GifWrap *wrap = limg->imgdata.aimg;
+    // 各フレームを破壊する
+    for (int i = 0; i < wrap->framecnt; ++i) {
+      XDestroyImage(wrap->frames[i]);
+    }
+  }
+
+  free(limg);
+}
+
 int main(int argc, char **argv) {
   XSetErrorHandler(XErrorHandlerd);
   if (argc < 2) {
@@ -64,7 +119,7 @@ int main(int argc, char **argv) {
     return 1;
   }
 
-  XImage *ximg = openimg(d, argv[1]);
+  LoliImg *ximg = openimg(d, argv[1]);
   if (ximg == NULL) {
     fprintf(stderr, "画像を開けられません： %s\n", argv[1]);
     XFreeGC(d, gc);
@@ -73,6 +128,9 @@ int main(int argc, char **argv) {
   }
 
   double scale = 1.0;
+  struct timeval tv;
+  gettimeofday(&tv, NULL);
+  unsigned long curframe = 1000000 * tv.tv_sec + tv.tv_usec;
 
   while (1) {
     XEvent e;
@@ -81,7 +139,12 @@ int main(int argc, char **argv) {
     if (e.type == Expose) {
       int nw = (int)(ximg->width * scale);
       int nh = (int)(ximg->height * scale);
-      XPutImage(d, w, gc, ximg, 0, 0, 0, 0, nw, nh);
+      if (ximg->type == STATIC) {
+        XPutImage(d, w, gc, ximg->imgdata.simg, 0, 0, 0, 0, nw, nh);
+      } else {
+        GifWrap *wrap = ximg->imgdata.aimg;
+        XPutImage(d, w, gc, wrap->frames[curframe], 0, 0, 0, 0, nw, nh);
+      }
     }
 
     if (e.type == KeyPress) {
@@ -98,7 +161,7 @@ int main(int argc, char **argv) {
 
   // 掃除
   XFreeGC(d, gc);
-  XDestroyImage(ximg);
+  GentleDestroyLoliImage(ximg);
   XDestroyWindow(d, w);
   XCloseDisplay(d);