Determine the format of an image file by its header data not by its file name suffix.

This commit is contained in:
Araki Ken
2014-03-01 16:16:48 +09:00
committed by Tatsuya Kinoshita
parent 0c0d4b5f38
commit e6856f2329

126
image.c
View File

@@ -628,86 +628,72 @@ getImage(Image * image, ParsedURL *current, int flag)
static int
parseImageHeader(char *path, u_int *width, u_int *height)
{
char *suffix;
FILE *fp;
u_char buf[8];
suffix = path + strlen(path);
if (strcasecmp(suffix - 5, ".jpeg") == 0 || strcasecmp(suffix - 4 , ".jpg") == 0) {
FILE *fp = fopen(path, "r");
if (fp) {
u_char buf[2];
if (fread(buf, 1, 2, fp) != 2 || memcmp(buf, "\xff\xd8", 2) != 0 ||
fseek(fp, 2, SEEK_CUR) < 0) /* 0xffe0 */
goto jpg_error;
if (!(fp = fopen(path, "r"))) return FALSE;
while (fread(buf, 1, 2, fp) == 2) {
size_t len = ((buf[0] << 8) | buf[1]) - 2;
if (fseek(fp, len, SEEK_CUR) < 0) goto jpg_error;
if (fread(buf, 1, 2, fp) == 2 && memcmp(buf, "\xff\xc0", 2) == 0) {
fseek(fp, 3, SEEK_CUR);
if (fread(buf, 1, 2, fp) == 2) {
*height = (buf[0] << 8) | buf[1];
if (fread(buf, 1, 2, fp) == 2) {
*width = (buf[0] << 8) | buf[1];
fclose(fp);
return TRUE;
}
}
break;
}
}
if (fread(buf, 1, 2, fp) != 2) goto error;
jpg_error:
fclose(fp);
return FALSE;
}
}
else if (strcasecmp(suffix - 4, ".png") == 0) {
FILE *fp = fopen(path, "r");
if (fp) {
u_char buf[8];
if (fread(buf, 1, 8, fp) != 8 ||
memcmp(buf, "\x89\x50\x4e\x47\x0d\x0a\x1a\x0a", 8) != 0 ||
fseek(fp, 8, SEEK_CUR) < 0)
goto png_error;
if (fread(buf, 1, 4, fp) == 4) {
*width = (buf[0] << 24) | (buf[1] << 16) | (buf[2] << 8) | buf[3];
if (fread(buf, 1, 4, fp) == 4) {
*height = (buf[0] << 24) | (buf[1] << 16) | (buf[2] << 8) | buf[3];
fclose(fp);
return TRUE;
}
}
png_error:
fclose(fp);
return FALSE;
}
}
else if (strcasecmp(suffix - 4, ".gif") == 0) {
FILE *fp = fopen(path, "r");
if (fp) {
u_char buf[3];
if (fread(buf, 1, 3, fp) != 3 || memcmp(buf, "GIF", 3) != 0 ||
fseek(fp, 3, SEEK_CUR) < 0) {
goto png_error;
}
if (fread(buf, 1, 2, fp) == 2) {
*width = (buf[1] << 8) | buf[0];
if (memcmp(buf, "\xff\xd8", 2) == 0) {
/* JPEG */
if (fseek(fp, 2, SEEK_CUR) < 0) goto error; /* 0xffe0 */
while (fread(buf, 1, 2, fp) == 2) {
size_t len = ((buf[0] << 8) | buf[1]) - 2;
if (fseek(fp, len, SEEK_CUR) < 0) goto error;
if (fread(buf, 1, 2, fp) == 2 &&
/* SOF0 or SOF2 */
(memcmp(buf, "\xff\xc0", 2) == 0 || memcmp(buf, "\xff\xc2", 2) == 0)) {
fseek(fp, 3, SEEK_CUR);
if (fread(buf, 1, 2, fp) == 2) {
*height = (buf[1] << 8) | buf[0];
fclose(fp);
return TRUE;
*height = (buf[0] << 8) | buf[1];
if (fread(buf, 1, 2, fp) == 2) {
*width = (buf[0] << 8) | buf[1];
goto success;
}
}
break;
}
}
gif_error:
fclose(fp);
return FALSE;
goto error;
}
if (fread(buf + 2, 1, 1, fp) != 1) goto error;
if (memcmp(buf, "GIF", 3) == 0) {
/* GIF */
if (fseek(fp, 3, SEEK_CUR) < 0) goto error;
if (fread(buf, 1, 2, fp) == 2) {
*width = (buf[1] << 8) | buf[0];
if (fread(buf, 1, 2, fp) == 2) {
*height = (buf[1] << 8) | buf[0];
goto success;
}
}
}
if (fread(buf + 3, 1, 5, fp) != 5) goto error;
if (memcmp(buf, "\x89\x50\x4e\x47\x0d\x0a\x1a\x0a", 8) == 0) {
/* PNG */
if (fseek(fp, 8, SEEK_CUR) < 0) goto error;
if (fread(buf, 1, 4, fp) == 4) {
*width = (buf[0] << 24) | (buf[1] << 16) | (buf[2] << 8) | buf[3];
if (fread(buf, 1, 4, fp) == 4) {
*height = (buf[0] << 24) | (buf[1] << 16) | (buf[2] << 8) | buf[3];
goto success;
}
}
}
error:
fprintf(stderr,"%s\n",path);
fclose(fp);
return FALSE;
success:
fclose(fp);
return TRUE;
}
int