83 lines
3.0 KiB
C
83 lines
3.0 KiB
C
//
|
|
// Created by marcsello on 03/11/2020.
|
|
//
|
|
|
|
#include "ciff_tools.h"
|
|
#include "stdbool.h"
|
|
|
|
uint8_t contains(const uint8_t* data, uint64_t data_len, uint8_t what) {
|
|
for (uint64_t i = 0; i < data_len; i++) {
|
|
if (data[i] == what) {
|
|
return true;
|
|
}
|
|
}
|
|
return false;
|
|
}
|
|
|
|
|
|
uint8_t parse_ciff_from_mem(const uint8_t* data, uint64_t data_len, uint64_t* width, uint64_t* height, uint64_t* pixel_data_starts) {
|
|
/**
|
|
* Igazából, ezek többnyire csak változatos ellenőrzések
|
|
* A függvény validálja a CIFF fájl tartalmát, majd ha ez sikeres volt, akkor megmondja
|
|
* - A kép dimenzióit
|
|
* - Hogy hol kezdődik a pixel információ a képben
|
|
* Az, hogy a kép információt kimásolja-e, az a programozóra van bízva.
|
|
*/
|
|
|
|
// Read out the static part of the header (If we have at least header bytes)
|
|
if (data_len < sizeof(ciff_static_header_t)) {
|
|
return CIFF_PARSE_HEADER_TOO_SHORT;
|
|
}
|
|
ciff_static_header_t* header_info = (struct ciff_static_header_t*)data;
|
|
|
|
// Do some preflight checks
|
|
// Check if the magic is valid...
|
|
if (header_info->magic != 0x43494646) {
|
|
return CIFF_PARSE_HEADER_BAD_MAGIC;
|
|
}
|
|
|
|
// Check if the fields in the header seems valid (none of the size fields larger than the whole file)
|
|
if ((header_info->header_size > data_len) || (header_info->content_size > data_len)) {
|
|
return CIFF_PARSE_HEADER_LENGTHS_INCORRECT;
|
|
}
|
|
|
|
if ((header_info->header_size+header_info->content_size) > data_len) {
|
|
return CIFF_PARSE_HEADER_LENGTHS_INCORRECT;
|
|
}
|
|
|
|
// Pre-Calculate some variables and check against those as well
|
|
uint64_t calculated_pixeldata_length_by_header = header_info->width * header_info->height * 3;
|
|
if (data_len < calculated_pixeldata_length_by_header) {
|
|
// The number of pixels defined in the header is larger than the while file
|
|
return CIFF_PARSE_HEADER_DIMENSIONS_INCORRECT;
|
|
}
|
|
|
|
if (calculated_pixeldata_length_by_header != header_info->content_size) {
|
|
return CIFF_PARSE_HEADER_DIMENSIONS_INCORRECT;
|
|
}
|
|
|
|
uint64_t calculated_total_length_by_header = calculated_pixeldata_length_by_header + header_info->header_size;
|
|
if (calculated_total_length_by_header != data_len) {
|
|
// The header + pixel data is not equals the length of the file
|
|
return CIFF_PARSE_HEADER_LENGTHS_INCORRECT;
|
|
}
|
|
|
|
// Do some other checks to validate the header
|
|
|
|
// According the specifications, the header must contain a newline character after the static fields
|
|
if (!contains(data+sizeof(struct ciff_static_header_t),header_info->header_size-sizeof(struct ciff_static_header_t),'\n')) {
|
|
return CIFF_PARSE_UNKNOWN_ERROR;
|
|
}
|
|
|
|
// According to specifications, the last byte of the header must be a \0
|
|
if (data[header_info->header_size-1] != 0) {
|
|
return CIFF_PARSE_UNKNOWN_ERROR;
|
|
}
|
|
|
|
// Set return data
|
|
*width = header_info->width;
|
|
*height = header_info->height;
|
|
*pixel_data_starts = header_info->header_size;
|
|
return CIFF_PARSE_SUCCESS;
|
|
|
|
} |