psxc/src/boot.c

#include "boot.h"

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

static const uint8_t MAGIC[0x10] = "PS-X EXE";
static const uint8_t RESERVED[0x10] = {0};

typedef struct __attribute__((packed))
{
    uint32_t pc;
    uint32_t gp;
    uint32_t addr_dest;
    uint32_t size_file;
    uint32_t addr_data;
    uint32_t size_data;
    uint32_t addr_bss;
    uint32_t size_bss;
} psx_header_t;

psx_header_t parse_psx_header(byte_arr_t *prgm)
{
    psx_header_t header;

    // TODO: Convert asserts into recoverable error
    assert(prgm->size >= 0x800);
    assert(memcmp(MAGIC, prgm->data, sizeof MAGIC) == 0);
    memcpy(&header, &prgm->data[sizeof MAGIC], sizeof header);

    assert(header.size_file == prgm->size - 0x800);
    assert(memcmp(RESERVED, &prgm->data[0x38], sizeof RESERVED) == 0);

    return header;
}

void boot_psx_prgm(byte_arr_t *prgm)
{
    psx_header_t header = parse_psx_header(prgm);

    printf("pc = %08x\n", header.pc);
    printf("gp = %08x\n", header.gp);
    printf("data = %08x (%u bytes)\n", header.addr_data, header.size_data);
    printf("bss = %08x (%u bytes)\n", header.addr_bss, header.size_bss);
    printf("dest = %08x\n", header.addr_dest);
    printf("size = %08x (%u bytes)\n", header.size_file, header.size_file);
}