ref: b4814b06b95ebc426b2f4c2783fe171d6adc52af
dir: /src/fix/main.c/
/*
* This file is part of RGBDS.
*
* Copyright (c) 2020, Eldred habert and RGBDS contributors.
*
* SPDX-License-Identifier: MIT
*/
#include <sys/types.h>
#include <sys/stat.h>
#include <assert.h>
#include <errno.h>
#include <inttypes.h>
#include <limits.h>
#include <stdarg.h>
#include <stdbool.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "extern/getopt.h"
#include "helpers.h"
#include "platform.h"
#include "version.h"
#define UNSPECIFIED 0x100 // May not be in byte range
#define BANK_SIZE 0x4000
/* Short options */
static const char *optstring = "Ccf:i:jk:l:m:n:p:r:st:Vv";
/*
* Equivalent long options
* Please keep in the same order as short opts
*
* Also, make sure long opts don't create ambiguity:
* A long opt's name should start with the same letter as its short opt,
* except if it doesn't create any ambiguity (`verbose` versus `version`).
* This is because long opt matching, even to a single char, is prioritized
* over short opt matching
*/
static struct option const longopts[] = {
{ "color-only", no_argument, NULL, 'C' },
{ "color-compatible", no_argument, NULL, 'c' },
{ "fix-spec", required_argument, NULL, 'f' },
{ "game-id", required_argument, NULL, 'i' },
{ "non-japanese", no_argument, NULL, 'j' },
{ "new-licensee", required_argument, NULL, 'k' },
{ "old-licensee", required_argument, NULL, 'l' },
{ "mbc-type", required_argument, NULL, 'm' },
{ "rom-version", required_argument, NULL, 'n' },
{ "pad-value", required_argument, NULL, 'p' },
{ "ram-size", required_argument, NULL, 'r' },
{ "sgb-compatible", no_argument, NULL, 's' },
{ "title", required_argument, NULL, 't' },
{ "version", no_argument, NULL, 'V' },
{ "validate", no_argument, NULL, 'v' },
{ NULL, no_argument, NULL, 0 }
};
static void printUsage(void)
{
fputs(
"Usage: rgbfix [-jsVv] [-C | -c] [-f <fix_spec>] [-i <game_id>] [-k <licensee>]\n"
" [-l <licensee_byte>] [-m <mbc_type>] [-n <rom_version>]\n"
" [-p <pad_value>] [-r <ram_size>] [-t <title_str>] [<file> ...]\n"
"Useful options:\n"
" -m, --mbc-type <value> set the MBC type byte to this value; refer\n"
" to the man page for a list of values\n"
" -p, --pad-value <value> pad to the next valid size using this value\n"
" -r, --ram-size <code> set the cart RAM size byte to this value\n"
" -V, --version print RGBFIX version and exit\n"
" -v, --validate fix the header logo and both checksums (-f lhg)\n"
"\n"
"For help, use `man rgbfix' or go to https://rgbds.gbdev.io/docs/\n",
stderr);
}
enum MbcType {
ROM = 0x00,
ROM_RAM = 0x08,
ROM_RAM_BATTERY = 0x09,
MBC1 = 0x01,
MBC1_RAM = 0x02,
MBC1_RAM_BATTERY = 0x03,
MBC2 = 0x05,
MBC2_BATTERY = 0x06,
MMM01 = 0x0B,
MMM01_RAM = 0x0C,
MMM01_RAM_BATTERY = 0x0D,
MBC3 = 0x11,
MBC3_TIMER_BATTERY = 0x0F,
MBC3_TIMER_RAM_BATTERY = 0x10,
MBC3_RAM = 0x12,
MBC3_RAM_BATTERY = 0x13,
MBC5 = 0x19,
MBC5_RAM = 0x1A,
MBC5_RAM_BATTERY = 0x1B,
MBC5_RUMBLE = 0x1C,
MBC5_RUMBLE_RAM = 0x1D,
MBC5_RUMBLE_RAM_BATTERY = 0x1E,
MBC6 = 0x20,
MBC7_SENSOR_RUMBLE_RAM_BATTERY = 0x22,
POCKET_CAMERA = 0xFC,
BANDAI_TAMA5 = 0xFD,
HUC3 = 0xFE,
HUC1_RAM_BATTERY = 0xFF,
// Error values
MBC_NONE = UNSPECIFIED, // No MBC specified, do not act on it
MBC_BAD, // Specified MBC does not exist / syntax error
MBC_WRONG_FEATURES, // MBC incompatible with specified features
MBC_BAD_RANGE, // MBC number out of range
};
/**
* @return False on failure
*/
static bool readMBCSlice(char const **name, char const *expected)
{
while (*expected) {
char c = *(*name)++;
if (c == '\0') // Name too short
return false;
if (c >= 'a' && c <= 'z') // Perform the comparison case-insensitive
c = c - 'a' + 'A';
else if (c == '_') // Treat underscores as spaces
c = ' ';
if (c != *expected++)
return false;
}
return true;
}
static enum MbcType parseMBC(char const *name)
{
if (name[0] >= '0' && name[0] <= '9') {
// Parse number, and return it as-is (unless it's too large)
char *endptr;
unsigned long mbc = strtoul(name, &endptr, 0);
if (*endptr)
return MBC_BAD;
if (mbc > 0xFF)
return MBC_BAD_RANGE;
return mbc;
} else {
// Begin by reading the MBC type:
uint16_t mbc;
char const *ptr = name;
// Trim off leading whitespace
while (*ptr == ' ' || *ptr == '\t')
ptr++;
#define tryReadSlice(expected) \
do { \
if (!readMBCSlice(&ptr, expected)) \
return MBC_BAD; \
} while (0)
switch (*ptr++) {
case 'R': // ROM / ROM_ONLY
case 'r':
tryReadSlice("OM");
// Handle optional " ONLY"
while (*ptr == ' ' || *ptr == '\t' || *ptr == '_')
ptr++;
if (*ptr == 'O' || *ptr == 'o') {
ptr++;
tryReadSlice("NLY");
}
mbc = ROM;
break;
case 'M': // MBC{1, 2, 3, 5, 6, 7} / MMM01
case 'm':
switch (*ptr++) {
case 'B':
case 'b':
switch (*ptr++) {
case 'C':
case 'c':
break;
default:
return MBC_BAD;
}
switch (*ptr++) {
case '1':
mbc = MBC1;
break;
case '2':
mbc = MBC2;
break;
case '3':
mbc = MBC3;
break;
case '5':
mbc = MBC5;
break;
case '6':
mbc = MBC6;
break;
case '7':
mbc = MBC7_SENSOR_RUMBLE_RAM_BATTERY;
break;
default:
return MBC_BAD;
}
break;
case 'M':
case 'm':
tryReadSlice("M01");
mbc = MMM01;
break;
default:
return MBC_BAD;
}
break;
case 'P': // POCKET_CAMERA
case 'p':
tryReadSlice("OCKET CAMERA");
mbc = POCKET_CAMERA;
break;
case 'B': // BANDAI_TAMA5
case 'b':
tryReadSlice("ANDAI TAMA5");
mbc = BANDAI_TAMA5;
break;
case 'T': // TAMA5
case 't':
tryReadSlice("AMA5");
mbc = BANDAI_TAMA5;
break;
case 'H': // HuC{1, 3}
case 'h':
tryReadSlice("UC");
switch (*ptr++) {
case '1':
mbc = HUC1_RAM_BATTERY;
break;
case '3':
mbc = HUC3;
break;
default:
return MBC_BAD;
}
break;
default:
return MBC_BAD;
}
// Read "additional features"
uint8_t features = 0;
#define RAM 0x80
#define BATTERY 0x40
#define TIMER 0x20
#define RUMBLE 0x10
#define SENSOR 0x08
for (;;) {
// Trim off trailing whitespace
while (*ptr == ' ' || *ptr == '\t' || *ptr == '_')
ptr++;
// If done, start processing "features"
if (!*ptr)
break;
// We expect a '+' at this point
if (*ptr++ != '+')
return MBC_BAD;
// Trim off leading whitespace
while (*ptr == ' ' || *ptr == '\t' || *ptr == '_')
ptr++;
switch (*ptr++) {
case 'B': // BATTERY
case 'b':
tryReadSlice("ATTERY");
features |= BATTERY;
break;
case 'R': // RAM or RUMBLE
case 'r':
switch (*ptr++) {
case 'U':
case 'u':
tryReadSlice("MBLE");
features |= RUMBLE;
break;
case 'A':
case 'a':
if (*ptr != 'M' && *ptr != 'm')
return MBC_BAD;
ptr++;
features |= RAM;
break;
default:
return MBC_BAD;
}
break;
case 'S': // SENSOR
case 's':
tryReadSlice("ENSOR");
features |= SENSOR;
break;
case 'T': // TIMER
case 't':
tryReadSlice("IMER");
features |= TIMER;
break;
default:
return MBC_BAD;
}
}
#undef tryReadSlice
switch (mbc) {
case ROM:
if (!features)
break;
mbc = ROM_RAM - 1;
static_assert(ROM_RAM + 1 == ROM_RAM_BATTERY, "Enum sanity check failed!");
static_assert(MBC1 + 1 == MBC1_RAM, "Enum sanity check failed!");
static_assert(MBC1 + 2 == MBC1_RAM_BATTERY, "Enum sanity check failed!");
static_assert(MMM01 + 1 == MMM01_RAM, "Enum sanity check failed!");
static_assert(MMM01 + 2 == MMM01_RAM_BATTERY, "Enum sanity check failed!");
// fallthrough
case MBC1:
case MMM01:
if (features == RAM)
mbc++;
else if (features == (RAM | BATTERY))
mbc += 2;
else if (features)
return MBC_WRONG_FEATURES;
break;
case MBC2:
if (features == BATTERY)
mbc = MBC2_BATTERY;
else if (features)
return MBC_WRONG_FEATURES;
break;
case MBC3:
// Handle timer, which also requires battery
if (features & (TIMER & BATTERY)) {
features &= ~(TIMER | BATTERY); // Reset those bits
mbc = MBC3_TIMER_BATTERY;
// RAM is handled below
}
static_assert(MBC3 + 1 == MBC3_RAM, "Enum sanity check failed!");
static_assert(MBC3 + 2 == MBC3_RAM_BATTERY, "Enum sanity check failed!");
static_assert(MBC3_TIMER_BATTERY + 1 == MBC3_TIMER_RAM_BATTERY,
"Enum sanity check failed!");
if (features == RAM)
mbc++;
else if (features == (RAM | BATTERY))
mbc += 2;
else if (features)
return MBC_WRONG_FEATURES;
break;
case MBC5:
if (features & RUMBLE) {
features &= ~RUMBLE;
mbc = MBC5_RUMBLE;
}
static_assert(MBC5 + 1 == MBC5_RAM, "Enum sanity check failed!");
static_assert(MBC5 + 2 == MBC5_RAM_BATTERY, "Enum sanity check failed!");
static_assert(MBC5_RUMBLE + 1 == MBC5_RUMBLE_RAM, "Enum sanity check failed!");
static_assert(MBC5_RUMBLE + 2 == MBC5_RUMBLE_RAM_BATTERY,
"Enum sanity check failed!");
if (features == RAM)
mbc++;
else if (features == (RAM | BATTERY))
mbc += 2;
else if (features)
return MBC_WRONG_FEATURES;
break;
case MBC6:
case POCKET_CAMERA:
case BANDAI_TAMA5:
case HUC3:
// No extra features accepted
if (features)
return MBC_WRONG_FEATURES;
break;
case MBC7_SENSOR_RUMBLE_RAM_BATTERY:
if (features != (SENSOR | RUMBLE | RAM | BATTERY))
return MBC_WRONG_FEATURES;
break;
case HUC1_RAM_BATTERY:
if (features != (RAM | BATTERY)) // HuC1 expects RAM+BATTERY
return MBC_WRONG_FEATURES;
break;
}
// Trim off trailing whitespace
while (*ptr == ' ' || *ptr == '\t')
ptr++;
// If there is still something past the whitespace, error out
if (*ptr)
return MBC_BAD;
return mbc;
}
}
static char const *mbcName(enum MbcType type)
{
switch (type) {
case ROM:
return "ROM";
case ROM_RAM:
return "ROM+RAM";
case ROM_RAM_BATTERY:
return "ROM+RAM+BATTERY";
case MBC1:
return "MBC1";
case MBC1_RAM:
return "MBC1+RAM";
case MBC1_RAM_BATTERY:
return "MBC1+RAM+BATTERY";
case MBC2:
return "MBC2";
case MBC2_BATTERY:
return "MBC2+BATTERY";
case MMM01:
return "MMM01";
case MMM01_RAM:
return "MMM01+RAM";
case MMM01_RAM_BATTERY:
return "MMM01+RAM+BATTERY";
case MBC3:
return "MBC3";
case MBC3_TIMER_BATTERY:
return "MBC3+TIMER+BATTERY";
case MBC3_TIMER_RAM_BATTERY:
return "MBC3+TIMER+RAM+BATTERY";
case MBC3_RAM:
return "MBC3+RAM";
case MBC3_RAM_BATTERY:
return "MBC3+RAM+BATTERY";
case MBC5:
return "MBC5";
case MBC5_RAM:
return "MBC5+RAM";
case MBC5_RAM_BATTERY:
return "MBC5+RAM+BATTERY";
case MBC5_RUMBLE:
return "MBC5+RUMBLE";
case MBC5_RUMBLE_RAM:
return "MBC5+RUMBLE+RAM";
case MBC5_RUMBLE_RAM_BATTERY:
return "MBC5+RUMBLE+RAM+BATTERY";
case MBC6:
return "MBC6";
case MBC7_SENSOR_RUMBLE_RAM_BATTERY:
return "MBC7+SENSOR+RUMBLE+RAM+BATTERY";
case POCKET_CAMERA:
return "POCKET CAMERA";
case BANDAI_TAMA5:
return "BANDAI TAMA5";
case HUC3:
return "HUC3";
case HUC1_RAM_BATTERY:
return "HUC1+RAM+BATTERY";
// Error values
case MBC_NONE:
case MBC_BAD:
case MBC_WRONG_FEATURES:
case MBC_BAD_RANGE:
unreachable_();
}
unreachable_();
}
static bool hasRAM(enum MbcType type)
{
switch (type) {
case ROM:
case MBC1:
case MBC2: // Technically has RAM, but not marked as such
case MBC2_BATTERY:
case MMM01:
case MBC3:
case MBC3_TIMER_BATTERY:
case MBC5:
case MBC5_RUMBLE:
case MBC6: // TODO: not sure
case BANDAI_TAMA5: // TODO: not sure
case MBC_NONE:
case MBC_BAD:
case MBC_WRONG_FEATURES:
case MBC_BAD_RANGE:
return false;
case ROM_RAM:
case ROM_RAM_BATTERY:
case MBC1_RAM:
case MBC1_RAM_BATTERY:
case MMM01_RAM:
case MMM01_RAM_BATTERY:
case MBC3_TIMER_RAM_BATTERY:
case MBC3_RAM:
case MBC3_RAM_BATTERY:
case MBC5_RAM:
case MBC5_RAM_BATTERY:
case MBC5_RUMBLE_RAM:
case MBC5_RUMBLE_RAM_BATTERY:
case MBC7_SENSOR_RUMBLE_RAM_BATTERY:
case POCKET_CAMERA:
case HUC3:
case HUC1_RAM_BATTERY:
return true;
}
unreachable_();
}
static uint8_t nbErrors;
static format_(printf, 1, 2) void report(char const *fmt, ...)
{
va_list ap;
va_start(ap, fmt);
vfprintf(stderr, fmt, ap);
va_end(ap);
if (nbErrors != UINT8_MAX)
nbErrors++;
}
static const uint8_t ninLogo[] = {
0xCE, 0xED, 0x66, 0x66, 0xCC, 0x0D, 0x00, 0x0B,
0x03, 0x73, 0x00, 0x83, 0x00, 0x0C, 0x00, 0x0D,
0x00, 0x08, 0x11, 0x1F, 0x88, 0x89, 0x00, 0x0E,
0xDC, 0xCC, 0x6E, 0xE6, 0xDD, 0xDD, 0xD9, 0x99,
0xBB, 0xBB, 0x67, 0x63, 0x6E, 0x0E, 0xEC, 0xCC,
0xDD, 0xDC, 0x99, 0x9F, 0xBB, 0xB9, 0x33, 0x3E
};
static enum { DMG, BOTH, CGB } model = DMG; // If DMG, byte is left alone
#define FIX_LOGO 0x80
#define TRASH_LOGO 0x40
#define FIX_HEADER_SUM 0x20
#define TRASH_HEADER_SUM 0x10
#define FIX_GLOBAL_SUM 0x08
#define TRASH_GLOBAL_SUM 0x04
static uint8_t fixSpec = 0;
static const char *gameID = NULL;
static uint8_t gameIDLen;
static bool japanese = true;
static const char *newLicensee = NULL;
static uint8_t newLicenseeLen;
static uint16_t oldLicensee = UNSPECIFIED;
static enum MbcType cartridgeType = MBC_NONE;
static uint16_t romVersion = UNSPECIFIED;
static uint16_t padValue = UNSPECIFIED;
static uint16_t ramSize = UNSPECIFIED;
static bool sgb = false; // If false, SGB flags are left alone
static const char *title = NULL;
static uint8_t titleLen;
static uint8_t maxTitleLen(void)
{
return gameID ? 11 : model != DMG ? 15 : 16;
}
static ssize_t readBytes(int fd, uint8_t *buf, size_t len)
{
// POSIX specifies that lengths greater than SSIZE_MAX yield implementation-defined results
assert(len <= SSIZE_MAX);
ssize_t total = 0;
while (len) {
ssize_t ret = read(fd, buf, len);
if (ret == -1 && errno != EINTR) // Return errors, unless we only were interrupted
return -1;
// EOF reached
if (ret == 0)
return total;
// If anything was read, accumulate it, and continue
if (ret != -1) {
total += ret;
len -= ret;
buf += ret;
}
}
return total;
}
static ssize_t writeBytes(int fd, void *buf, size_t len)
{
// POSIX specifies that lengths greater than SSIZE_MAX yield implementation-defined results
assert(len <= SSIZE_MAX);
ssize_t total = 0;
while (len) {
ssize_t ret = write(fd, buf, len);
if (ret == -1 && errno != EINTR) // Return errors, unless we only were interrupted
return -1;
// EOF reached
if (ret == 0)
return total;
// If anything was read, accumulate it, and continue
if (ret != -1) {
total += ret;
len -= ret;
}
}
return total;
}
/**
* @param rom0 A pointer to rom0
* @param startAddr What address to begin checking from
* @param size How many bytes to check
* @param areaName Name to be displayed in the warning message
*/
static void warnNonZero(uint8_t *rom0, uint16_t startAddr, uint8_t size, char const *areaName)
{
for (uint8_t i = 0; i < size; i++) {
if (rom0[i + startAddr] != 0) {
fprintf(stderr, "warning: Overwrote a non-zero byte in the %s\n", areaName);
break;
}
}
}
/**
* @param input File descriptor to be used for reading
* @param output File descriptor to be used for writing, may be equal to `input`
* @param name The file's name, to be displayed for error output
* @param fileSize The file's size if known, 0 if not.
*/
static void processFile(int input, int output, char const *name, off_t fileSize)
{
// Both of these should be true for seekable files, and neither otherwise
if (input == output)
assert(fileSize != 0);
else
assert(fileSize == 0);
uint8_t rom0[BANK_SIZE];
ssize_t rom0Len = readBytes(input, rom0, sizeof(rom0));
if (rom0Len == -1) {
report("FATAL: Failed to read \"%s\"'s header: %s\n", name, strerror(errno));
return;
} else if (rom0Len < 0x150) {
report("FATAL: \"%s\" too short, expected at least 336 ($150) bytes, got only %jd\n",
name, (intmax_t)rom0Len);
return;
}
// Accept partial reads if the file contains at least the header
if (fixSpec & (FIX_LOGO | TRASH_LOGO)) {
warnNonZero(rom0, 0x0104, sizeof(ninLogo), "Nintendo logo");
if (fixSpec & FIX_LOGO) {
memcpy(&rom0[0x104], ninLogo, sizeof(ninLogo));
} else {
for (uint8_t i = 0; i < sizeof(ninLogo); i++)
rom0[i + 0x104] = ~ninLogo[i];
}
}
if (title) {
warnNonZero(rom0, 0x134, titleLen, "title");
memcpy(&rom0[0x134], title, titleLen);
}
if (gameID) {
warnNonZero(rom0, 0x13f, gameIDLen, "manufacturer code");
memcpy(&rom0[0x13f], gameID, gameIDLen);
}
if (model != DMG) {
warnNonZero(rom0, 0x143, 1, "CGB flag");
rom0[0x143] = model == BOTH ? 0x80 : 0xc0;
}
if (newLicensee) {
warnNonZero(rom0, 0x144, newLicenseeLen, "new licensee code");
memcpy(&rom0[0x144], newLicensee, newLicenseeLen);
}
if (sgb) {
warnNonZero(rom0, 0x146, 1, "SGB flag");
rom0[0x146] = 0x03;
}
// If a valid MBC was specified...
if (cartridgeType < MBC_NONE) {
warnNonZero(rom0, 0x147, 1, "cartridge type");
rom0[0x147] = cartridgeType;
}
if (ramSize != UNSPECIFIED) {
warnNonZero(rom0, 0x149, 1, "RAM size");
rom0[0x149] = ramSize;
}
if (!japanese) {
warnNonZero(rom0, 0x14a, 1, "destination code");
rom0[0x14a] = 0x01;
}
if (oldLicensee != UNSPECIFIED) {
warnNonZero(rom0, 0x14b, 1, "old licensee code");
rom0[0x14b] = oldLicensee;
}
if (romVersion != UNSPECIFIED) {
warnNonZero(rom0, 0x14c, 1, "mask ROM version number");
rom0[0x14c] = romVersion;
}
// Remain to be handled the ROM size, and header checksum.
// The latter depends on the former, and so will be handled after it.
// The former requires knowledge of the file's total size, so read that first.
uint16_t globalSum = 0;
// To keep file sizes fairly reasonable, we'll cap the amount of banks at 65536
// Official mappers only go up to 512 banks, but at least the TPP1 spec allows up to
// 65536 banks = 1 GiB.
// This should be reasonable for the time being, and may be extended later.
uint8_t *romx = NULL; // Pointer to ROMX banks when they've been buffered
uint32_t nbBanks = 1; // Number of banks *targeted*, including ROM0
size_t totalRomxLen = 0; // *Actual* size of ROMX data
uint8_t bank[BANK_SIZE]; // Temp buffer used to store a whole bank's worth of data
// Handle ROMX
if (input == output) {
if (fileSize >= 0x10000 * BANK_SIZE) {
report("FATAL: \"%s\" has more than 65536 banks\n", name);
return;
}
// This should be guaranteed from the size cap...
static_assert(0x10000 * BANK_SIZE <= SSIZE_MAX, "Max input file size too large for OS");
// Compute number of banks and ROMX len from file size
nbBanks = (fileSize + (BANK_SIZE - 1)) / BANK_SIZE;
// = ceil(totalRomxLen / BANK_SIZE)
totalRomxLen = fileSize >= BANK_SIZE ? fileSize - BANK_SIZE : 0;
} else if (rom0Len == BANK_SIZE) {
// Copy ROMX when reading a pipe, and we're not at EOF yet
for (;;) {
romx = realloc(romx, nbBanks * BANK_SIZE);
if (!romx) {
report("FATAL: Failed to realloc ROMX buffer: %s\n",
strerror(errno));
return;
}
ssize_t bankLen = readBytes(input, &romx[(nbBanks - 1) * BANK_SIZE],
BANK_SIZE);
// Update bank count, ONLY IF at least one byte was read
if (bankLen) {
// We're gonna read another bank, check that it won't be too much
static_assert(0x10000 * BANK_SIZE <= SSIZE_MAX, "Max input file size too large for OS");
if (nbBanks == 0x10000) {
report("FATAL: \"%s\" has more than 65536 banks\n", name);
free(romx);
return;
}
nbBanks++;
// Update global checksum, too
for (uint16_t i = 0; i < bankLen; i++)
globalSum += romx[totalRomxLen + i];
totalRomxLen += bankLen;
}
// Stop when an incomplete bank has been read
if (bankLen != BANK_SIZE)
break;
}
}
// Handle setting the ROM size if padding was requested
// Pad to the next valid power of 2. This is because padding is required by flashers, which
// flash to ROM chips, whose size is always a power of 2... so there'd be no point in
// padding to something else.
// Additionally, a ROM must be at least 32k, so we guarantee a whole amount of banks...
if (padValue != UNSPECIFIED) {
// We want at least 2 banks
if (nbBanks == 1) {
if (rom0Len != sizeof(rom0)) {
memset(&rom0[rom0Len], padValue, sizeof(rom0) - rom0Len);
// The global checksum hasn't taken ROM0 into consideration yet!
// ROM0 was padded, so treat it as entirely written: update its size
// Update how many bytes were read in total, too
rom0Len = sizeof(rom0);
}
nbBanks = 2;
} else {
assert(rom0Len == sizeof(rom0));
}
assert(nbBanks >= 2);
// Alter number of banks to reflect required value
// x&(x-1) is zero iff x is a power of 2, or 0; we know for sure it's non-zero,
// so this is true (non-zero) when we don't have a power of 2
if (nbBanks & (nbBanks - 1))
nbBanks = 1 << (CHAR_BIT * sizeof(nbBanks) - clz(nbBanks));
// Write final ROM size
rom0[0x148] = ctz(nbBanks / 2);
// Alter global checksum based on how many bytes will be added (not counting ROM0)
globalSum += padValue * ((nbBanks - 1) * BANK_SIZE - totalRomxLen);
}
// Handle the header checksum after the ROM size has been written
if (fixSpec & (FIX_HEADER_SUM | TRASH_HEADER_SUM)) {
uint8_t sum = 0;
for (uint16_t i = 0x134; i < 0x14d; i++)
sum -= rom0[i] + 1;
warnNonZero(rom0, 0x14d, 1, "header checksum");
rom0[0x14d] = fixSpec & TRASH_HEADER_SUM ? ~sum : sum;
}
if (fixSpec & (FIX_GLOBAL_SUM | TRASH_GLOBAL_SUM)) {
// Computation of the global checksum assumes 0s being stored in its place
rom0[0x14e] = 0;
rom0[0x14f] = 0;
for (uint16_t i = 0; i < rom0Len; i++)
globalSum += rom0[i];
// Pipes have already read ROMX and updated globalSum, but not regular files
if (input == output) {
for (;;) {
ssize_t romxLen = readBytes(input, bank, sizeof(bank));
for (uint16_t i = 0; i < romxLen; i++)
globalSum += bank[i];
if (romxLen != sizeof(bank))
break;
}
}
if (fixSpec & TRASH_GLOBAL_SUM)
globalSum = ~globalSum;
warnNonZero(rom0, 0x14e, 2, "global checksum");
rom0[0x14e] = globalSum >> 8;
rom0[0x14f] = globalSum & 0xff;
}
// In case the output depends on the input, reset to the beginning of the file, and only
// write the header
if (input == output) {
if (lseek(output, 0, SEEK_SET) == (off_t)-1) {
report("FATAL: Failed to rewind \"%s\": %s\n", name, strerror(errno));
goto free_romx;
}
// If modifying the file in-place, we only need to edit the header
// However, padding may have modified ROM0 (added padding), so don't in that case
if (padValue == UNSPECIFIED)
rom0Len = 0x150;
}
ssize_t writeLen = writeBytes(output, rom0, rom0Len);
if (writeLen == -1) {
report("FATAL: Failed to write \"%s\"'s ROM0: %s\n", name, strerror(errno));
goto free_romx;
} else if (writeLen < rom0Len) {
report("FATAL: Could only write %jd of \"%s\"'s %jd ROM0 bytes\n",
(intmax_t)writeLen, name, (intmax_t)rom0Len);
goto free_romx;
}
// Output ROMX if it was buffered
if (romx) {
// The value returned is either -1, or smaller than `totalRomxLen`,
// so it's fine to cast to `size_t`
writeLen = writeBytes(output, romx, totalRomxLen);
if (writeLen == -1) {
report("FATAL: Failed to write \"%s\"'s ROMX: %s\n", name, strerror(errno));
goto free_romx;
} else if ((size_t)writeLen < totalRomxLen) {
report("FATAL: Could only write %jd of \"%s\"'s %zu ROMX bytes\n",
(intmax_t)writeLen, name, totalRomxLen);
goto free_romx;
}
}
// Output padding
if (padValue != UNSPECIFIED) {
if (input == output) {
if (lseek(output, 0, SEEK_END) == (off_t)-1) {
report("FATAL: Failed to seek to end of \"%s\": %s\n",
name, strerror(errno));
goto free_romx;
}
}
memset(bank, padValue, sizeof(bank));
size_t len = (nbBanks - 1) * BANK_SIZE - totalRomxLen; // Don't count ROM0!
while (len) {
static_assert(sizeof(bank) <= SSIZE_MAX, "Bank too large for reading");
size_t thisLen = len > sizeof(bank) ? sizeof(bank) : len;
ssize_t ret = writeBytes(output, bank, thisLen);
// The return value is either -1, or at most `thisLen`,
// so it's fine to cast to `size_t`
if ((size_t)ret != thisLen) {
report("FATAL: Failed to write \"%s\"'s padding: %s\n",
name, strerror(errno));
break;
}
len -= thisLen;
}
}
free_romx:
free(romx);
}
static bool processFilename(char const *name)
{
nbErrors = 0;
if (!strcmp(name, "-")) {
setmode(STDIN_FILENO, O_BINARY);
setmode(STDOUT_FILENO, O_BINARY);
name = "<stdin>";
processFile(STDIN_FILENO, STDOUT_FILENO, name, 0);
} else {
// POSIX specifies that the results of O_RDWR on a FIFO are undefined.
// However, this is necessary to avoid a TOCTTOU, if the file was changed between
// `stat()` and `open(O_RDWR)`, which could trigger the UB anyway.
// Thus, we're going to hope that either the `open` fails, or it succeeds but IO
// operations may fail, all of which we handle.
int input = open(name, O_RDWR | O_BINARY);
struct stat stat;
if (input == -1) {
report("FATAL: Failed to open \"%s\" for reading+writing: %s\n",
name, strerror(errno));
goto fail;
}
if (fstat(input, &stat) == -1) {
report("FATAL: Failed to stat \"%s\": %s\n", name, strerror(errno));
} else if (!S_ISREG(stat.st_mode)) { // FIXME: Do we want to support other types?
report("FATAL: \"%s\" is not a regular file, and thus cannot be modified in-place\n",
name);
} else if (stat.st_size < 0x150) {
// This check is in theory redundant with the one in `processFile`, but it
// prevents passing a file size of 0, which usually indicates pipes
report("FATAL: \"%s\" too short, expected at least 336 ($150) bytes, got only %jd\n",
name, (intmax_t)stat.st_size);
} else {
processFile(input, input, name, stat.st_size);
}
close(input);
}
if (nbErrors)
fail:
fprintf(stderr, "Fixing \"%s\" failed with %u error%s\n",
name, nbErrors, nbErrors == 1 ? "" : "s");
return nbErrors;
}
int main(int argc, char *argv[])
{
nbErrors = 0;
int ch;
while ((ch = musl_getopt_long_only(argc, argv, optstring, longopts, NULL)) != -1) {
switch (ch) {
size_t len;
#define parseByte(output, name) \
do { \
char *endptr; \
unsigned long tmp; \
\
if (musl_optarg[0] == 0) { \
report("error: Argument to option '" name "' may not be empty\n"); \
} else { \
if (musl_optarg[0] == '$') { \
tmp = strtoul(&musl_optarg[1], &endptr, 16); \
} else { \
tmp = strtoul(musl_optarg, &endptr, 0); \
} \
if (*endptr) \
report("error: Expected number as argument to option '" name "', got %s\n", \
musl_optarg); \
else if (tmp > 0xFF) \
report("error: Argument to option '" name "' is larger than 255: %lu\n", tmp); \
else \
output = tmp; \
} \
} while (0)
case 'C':
case 'c':
model = ch == 'c' ? BOTH : CGB;
if (titleLen > 15) {
titleLen = 15;
fprintf(stderr, "warning: Truncating title \"%s\" to 15 chars\n",
title);
}
break;
case 'f':
fixSpec = 0;
while (*musl_optarg) {
switch (*musl_optarg) {
#define SPEC_l FIX_LOGO
#define SPEC_L TRASH_LOGO
#define SPEC_h FIX_HEADER_SUM
#define SPEC_H TRASH_HEADER_SUM
#define SPEC_g FIX_GLOBAL_SUM
#define SPEC_G TRASH_GLOBAL_SUM
#define overrideSpec(new, bad) \
do { \
if (fixSpec & SPEC_##bad) \
fprintf(stderr, \
"warning: '" #new "' overriding '" #bad "' in fix spec\n"); \
fixSpec = (fixSpec & ~SPEC_##bad) | SPEC_##new; \
} while (0)
case 'l':
overrideSpec(l, L);
break;
case 'L':
overrideSpec(L, l);
break;
case 'h':
overrideSpec(h, H);
break;
case 'H':
overrideSpec(H, h);
break;
case 'g':
overrideSpec(g, G);
break;
case 'G':
overrideSpec(G, g);
break;
default:
fprintf(stderr, "warning: Ignoring '%c' in fix spec\n",
*musl_optarg);
#undef overrideSpec
}
musl_optarg++;
}
break;
case 'i':
gameID = musl_optarg;
len = strlen(gameID);
if (len > 4) {
len = 4;
fprintf(stderr, "warning: Truncating game ID \"%s\" to 4 chars\n",
gameID);
}
gameIDLen = len;
if (titleLen > 11) {
titleLen = 11;
fprintf(stderr, "warning: Truncating title \"%s\" to 11 chars\n",
title);
}
break;
case 'j':
japanese = false;
break;
case 'k':
newLicensee = musl_optarg;
len = strlen(newLicensee);
if (len > 2) {
len = 2;
fprintf(stderr,
"warning: Truncating new licensee \"%s\" to 2 chars\n",
newLicensee);
}
newLicenseeLen = len;
break;
case 'l':
parseByte(oldLicensee, "l");
break;
case 'm':
cartridgeType = parseMBC(musl_optarg);
if (cartridgeType == MBC_BAD) {
report("error: Unknown MBC \"%s\"\n", musl_optarg);
} else if (cartridgeType == MBC_WRONG_FEATURES) {
report("error: Features incompatible with MBC (\"%s\")\n",
musl_optarg);
} else if (cartridgeType == MBC_BAD_RANGE) {
report("error: Specified MBC ID out of range 0-255: %s\n",
musl_optarg);
} else if (cartridgeType == ROM_RAM || cartridgeType == ROM_RAM_BATTERY) {
fprintf(stderr, "warning: ROM+RAM / ROM+RAM+BATTERY are under-specified and poorly supported\n");
}
break;
case 'n':
parseByte(romVersion, "n");
break;
case 'p':
parseByte(padValue, "p");
break;
case 'r':
parseByte(ramSize, "r");
break;
case 's':
sgb = true;
break;
case 't':
title = musl_optarg;
len = strlen(title);
uint8_t maxLen = maxTitleLen();
if (len > maxLen) {
len = maxLen;
fprintf(stderr, "warning: Truncating title \"%s\" to %u chars\n",
title, maxLen);
}
titleLen = len;
break;
case 'V':
printf("rgbfix %s\n", get_package_version_string());
exit(0);
case 'v':
fixSpec = FIX_LOGO | FIX_HEADER_SUM | FIX_GLOBAL_SUM;
break;
default:
fprintf(stderr, "FATAL: unknown option '%c'\n", ch);
printUsage();
exit(1);
}
#undef parseByte
}
if (ramSize != UNSPECIFIED && cartridgeType < UNSPECIFIED) {
if (cartridgeType == ROM_RAM || cartridgeType == ROM_RAM_BATTERY) {
if (ramSize != 1)
fprintf(stderr, "warning: MBC \"%s\" should have 2kiB of RAM (-r 1)\n",
mbcName(cartridgeType));
} else if (hasRAM(cartridgeType)) {
if (!ramSize) {
fprintf(stderr,
"warning: MBC \"%s\" has RAM, but RAM size was set to 0\n",
mbcName(cartridgeType));
} else if (ramSize == 1) {
fprintf(stderr,
"warning: RAM size 1 (2 kiB) was specified for MBC \"%s\"\n",
mbcName(cartridgeType));
} // TODO: check possible values?
} else if (ramSize) {
fprintf(stderr,
"warning: MBC \"%s\" has no RAM, but RAM size was set to %u\n",
mbcName(cartridgeType), ramSize);
}
}
if (sgb && oldLicensee != UNSPECIFIED && oldLicensee != 0x33)
fprintf(stderr,
"warning: SGB compatibility enabled, but old licensee is %#x, not 0x33\n",
oldLicensee);
argv += musl_optind;
bool failed = nbErrors;
if (!*argv) {
failed |= processFilename("-");
} else {
do {
failed |= processFilename(*argv);
} while (*++argv);
}
return failed;
}