consolidation of various example repos/gists

c/ani2png.c

@@ -0,0 +1,127 @@
+//build: gcc ani2png.c -o ani2png
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+void ReadFile(char *name);
+int teststring(char *buffer, int start);
+
+int main(int argc, char **argv)
+{
+  if (argc != 2)
+  {
+    fprintf(stderr, "Usage: ani2png /path.ani");
+    return 0;
+  }
+  ReadFile(*(argv + 1));
+  return 0;
+}
+
+int teststring(char *buffer, int start)
+{
+  if (*(buffer + start) == 0x69)
+  {
+    if (*(buffer + start + 1) == 0x63)
+    {
+      if (*(buffer + start + 2) == 0x6f)
+      {
+        if (*(buffer + start + 3) == 0x6e)
+        {
+          return 1;
+        }
+      }
+    }
+  }
+  else
+    return 0;
+}
+
+void ReadFile(char *name)
+{
+  FILE *file;
+  char *buffer, *fileName;
+  unsigned long fileLen;
+
+  if (!strstr(name, ".ani"))
+  {
+    fprintf(stderr, "Usage: ani2png /path.ani");
+    return;
+  }
+
+  fileName = malloc(strlen(name) + 1);
+  strcpy(fileName, name);
+  *strstr(fileName, ".ani") = '\0';
+
+  file = fopen(name, "rb");
+
+  fseek(file, 0, SEEK_END);
+  fileLen = ftell(file);
+  fseek(file, 0, SEEK_SET);
+
+  buffer = (char *)malloc(fileLen + 1);
+
+  fread(buffer, fileLen, 1, file);
+  fclose(file);
+
+  char *new_png_name = malloc(strlen(name) + 5);
+
+  char png_counter_string[5];
+  int i, j, png_counter = 1;
+  FILE *png_image;
+
+  for (i = 0; i <= fileLen; i++)
+  {
+    if (png_counter == 9999)
+    {
+      free(fileName);
+      free(buffer);
+      free(new_png_name);
+      return;
+    }
+
+    if ((i + 4 <= fileLen) && teststring(buffer, i) == 1)
+    {
+      sprintf(png_counter_string, "%d", png_counter);
+      strcpy(new_png_name, fileName);
+      strcat(new_png_name, png_counter_string);
+      strcat(new_png_name, ".png");
+      png_counter++;
+
+      png_image = fopen(new_png_name, "wb");
+      if (!png_image)
+      {
+        fprintf(stderr, "Unable to open file %s.\n", new_png_name);
+        free(fileName);
+        free(buffer);
+        free(new_png_name);
+        return;
+      }
+
+      j = 8;
+      while (i + j + 4 <= fileLen)
+      {
+        if (teststring(buffer, i + j + 1) == 1)
+          break;
+        if (j == 10)
+          putc(0x01, png_image);
+        else
+          putc(*(buffer + i + j), png_image);
+        j++;
+      }
+      if (i + j <= fileLen)
+        putc(*(buffer + i + j), png_image);
+      if (fileLen - i - j <= 3)
+      {
+        putc(*(buffer + i + j + 1), png_image);
+        putc(*(buffer + i + j + 2), png_image);
+      }
+      fclose(png_image);
+      i += j;
+    }
+  }
+
+  free(new_png_name);
+  free(buffer);
+  free(fileName);
+}