nese/src/ines.c

#include <string.h>

#include "ines.h"
#include "nes.h"


int ines_check_mem(void* mem) {
    int status = 0;
    ines_Header *hdr = (ines_Header*)mem;

    if (0 != memcmp(hdr->magic, ines_magic, sizeof(hdr->magic))) {
        INES_ERR("Bad file magic: expected '%.4s', got '%.4s'",
                 ines_magic, hdr->magic);
        status = -1;
    }

    return status;
}

int ines_check(ines_Header* ret, FILE* file) {
    int status = 0;
    ines_Header hdr = {0};

    if (1 != fread(&hdr, sizeof(ines_Header), 1, file)) {
        INES_ERR("Failed to read header");
        status = -1;
    }

    if (0 == status) {
        status = ines_check_mem(&hdr);
    }

    if (0 == status && NULL != ret) {
        *ret = hdr;
    }

    return status;
}