raw2gba.c

/* raw2gba.c
 * this program converts raw byte files into C header files
 * this can be used to load raw signed 8-bit audio data into the Game Boy Advance */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

/* this keeps the output header file from having very long lines */
#define LINE_LIMIT 11

int main(int argc, char** argv) {
    FILE* input;
    FILE* output;
    int i, length;

    if (argc != 2) {
        fprintf(stderr, "Usage: raw2gba input.raw\n");
        return -1;
    }

    /* open input file */
    input = fopen(argv[1], "r");
    if (!input) {
        fprintf(stderr, "Error: could not open %s for reading.\n", argv[1]);
        return -1;
    }

    /* see how many bytes it is */
    fseek(input, 0, SEEK_END);
    length = ftell(input);
    fseek(input, 0, SEEK_SET);

    /* load all of the bytes into an array */
    signed char* bytes = malloc(length * sizeof(signed char));
    fread(bytes, length, 1, input);

    /* find the base name of the input file w/o extension */
    char base[strlen(argv[1]) + 1];
    strcpy(base, argv[1]);
    base[strlen(argv[1]) - 4] = '\0';

    /* open output file which is same name but with .h instead of .raw */
    char output_name[strlen(base) + 3];
    sprintf(output_name, "%s.h", base);
    output = fopen(output_name, "w");
    if (!output) {
        fprintf(stderr, "Error: could not open %s for reading.\n", output_name);
        return -1;
    }

    /* the name of the array and such is the base name of file, but w/ no direcotries */
    char* name = base;
    while (strstr(name, "/") != NULL) {
        name = strstr(name, "/") + 1;
    }

    /* dump some preamble */
    fprintf(output, "/* %s.h\n * generated by raw2gba */\n\n", name);
    fprintf(output, "#define %s_bytes %d\n\n", name, length);
    fprintf(output, "const signed char %s [] = {\n    ", name);

    /* print the first byte */
    int line_counter = 1;
    fprintf(output, "0x%02X", bytes[0] & 0xff);

    for (i = 1; i < length; i++) {
        /* print a comma after the last byte */
        fprintf(output, ", ");

        /* go to a new line if needed */
        if (line_counter > LINE_LIMIT) {
            fprintf(output, "\n    ");
            line_counter = 0;
        }

        /* print the next bytw */
        line_counter++;
        fprintf(output, "0x%02X", bytes[i] & 0xff);
    }
    fprintf(output, "\n};\n\n"); 

    /* clean things up */
    free(bytes);
    fclose(input);
    fclose(output); 

    return 0;
}