feat(png): Validate signiture header

1 files changed, 29 insertions, 0 deletions

diff --git a/include/tinyff/image/png.h b/include/tinyff/image/png.h
new file mode 100644
index 0000000..caed675
--- /dev/null
+++ b/include/tinyff/image/png.h
@@ -0,0 +1,29 @@
+#ifndef PNG_H
+#define PNG_H
+
+#include <stdint.h>
+#include <stdio.h>
+#include <stdbool.h>
+#include <string.h>
+
+#include "tinyff/result.h"
+
+static const unsigned char PNG_SIGNATURE[8] = {
+    0x89, 'P', 'N', 'G', 0x0D, 0x0A, 0x1A, 0x0A
+};
+
+typedef struct {
+    FILE *raw;
+    uint32_t width;
+    uint32_t height;
+    uint8_t bit_depth;
+    uint8_t color_type;
+    uint8_t *pixels;
+    size_t count_pixels;
+    bool valid;
+} ff_png_ctx;
+
+ff_result ff_png_isvalid(FILE *file);
+ff_png_ctx *ff_open_png(const char *filepath);
+
+#endif