ref: a52a00a9ca7753ef41814b55878b510e8dc80b7b
dir: /src/link/main.c/
/*
* This file is part of RGBDS.
*
* Copyright (c) 1997-2019, Carsten Sorensen and RGBDS contributors.
*
* SPDX-License-Identifier: MIT
*/
#include <assert.h>
#include <inttypes.h>
#include <limits.h>
#include <stdbool.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#include <sys/types.h>
#include "link/assign.h"
#include "link/object.h"
#include "link/output.h"
#include "link/patch.h"
#include "link/section.h"
#include "link/script.h"
#include "link/symbol.h"
#include "extern/getopt.h"
#include "error.h"
#include "linkdefs.h"
#include "platform.h"
#include "version.h"
bool isDmgMode; // -d
char *linkerScriptName; // -l
char const *mapFileName; // -m
bool noSymInMap; // -M
char const *symFileName; // -n
char const *overlayFileName; // -O
char const *outputFileName; // -o
uint8_t padValue; // -p
// Setting these three to 0 disables the functionality
uint16_t scrambleROMX = 0; // -S
uint8_t scrambleWRAMX = 0;
uint8_t scrambleSRAM = 0;
bool is32kMode; // -t
bool beVerbose; // -v
bool isWRA0Mode; // -w
bool disablePadding; // -x
static uint32_t nbErrors = 0;
// Helper function to dump a file stack to stderr
char const *dumpFileStack(struct FileStackNode const *node)
{
char const *lastName;
if (node->parent) {
lastName = dumpFileStack(node->parent);
// REPT nodes use their parent's name
if (node->type != NODE_REPT)
lastName = node->name;
fprintf(stderr, "(%" PRIu32 ") -> %s", node->lineNo, lastName);
if (node->type == NODE_REPT) {
for (uint32_t i = 0; i < node->reptDepth; i++)
fprintf(stderr, "::REPT~%" PRIu32, node->iters[i]);
}
} else {
assert(node->type != NODE_REPT);
lastName = node->name;
fputs(lastName, stderr);
}
return lastName;
}
void warning(struct FileStackNode const *where, uint32_t lineNo, char const *fmt, ...)
{
va_list ap;
fputs("warning: ", stderr);
if (where) {
dumpFileStack(where);
fprintf(stderr, "(%" PRIu32 "): ", lineNo);
}
va_start(ap, fmt);
vfprintf(stderr, fmt, ap);
va_end(ap);
putc('\n', stderr);
}
void error(struct FileStackNode const *where, uint32_t lineNo, char const *fmt, ...)
{
va_list ap;
fputs("error: ", stderr);
if (where) {
dumpFileStack(where);
fprintf(stderr, "(%" PRIu32 "): ", lineNo);
}
va_start(ap, fmt);
vfprintf(stderr, fmt, ap);
va_end(ap);
putc('\n', stderr);
if (nbErrors != UINT32_MAX)
nbErrors++;
}
void argErr(char flag, char const *fmt, ...)
{
va_list ap;
fprintf(stderr, "error: Invalid argument for option '%c': ", flag);
va_start(ap, fmt);
vfprintf(stderr, fmt, ap);
va_end(ap);
putc('\n', stderr);
if (nbErrors != UINT32_MAX)
nbErrors++;
}
_Noreturn void fatal(struct FileStackNode const *where, uint32_t lineNo, char const *fmt, ...)
{
va_list ap;
fputs("FATAL: ", stderr);
if (where) {
dumpFileStack(where);
fprintf(stderr, "(%" PRIu32 "): ", lineNo);
}
va_start(ap, fmt);
vfprintf(stderr, fmt, ap);
va_end(ap);
putc('\n', stderr);
if (nbErrors != UINT32_MAX)
nbErrors++;
fprintf(stderr, "Linking aborted after %" PRIu32 " error%s\n", nbErrors,
nbErrors == 1 ? "" : "s");
exit(1);
}
FILE *openFile(char const *fileName, char const *mode)
{
if (!fileName)
return NULL;
FILE *file;
if (strcmp(fileName, "-") != 0)
file = fopen(fileName, mode);
else if (mode[0] == 'r')
file = fdopen(0, mode);
else
file = fdopen(1, mode);
if (!file)
err("Could not open file \"%s\"", fileName);
return file;
}
// Short options
static const char *optstring = "dl:m:Mn:O:o:p:S:s:tVvWwx";
/*
* 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[] = {
{ "dmg", no_argument, NULL, 'd' },
{ "linkerscript", required_argument, NULL, 'l' },
{ "map", required_argument, NULL, 'm' },
{ "no-sym-in-map", no_argument, NULL, 'M' },
{ "sym", required_argument, NULL, 'n' },
{ "overlay", required_argument, NULL, 'O' },
{ "output", required_argument, NULL, 'o' },
{ "pad", required_argument, NULL, 'p' },
{ "scramble", required_argument, NULL, 'S' },
{ "smart", required_argument, NULL, 's' },
{ "tiny", no_argument, NULL, 't' },
{ "version", no_argument, NULL, 'V' },
{ "verbose", no_argument, NULL, 'v' },
{ "wramx", no_argument, NULL, 'w' },
{ "nopad", no_argument, NULL, 'x' },
{ NULL, no_argument, NULL, 0 }
};
// Prints the program's usage to stdout.
static void printUsage(void)
{
fputs(
"Usage: rgblink [-dMtVvwx] [-l script] [-m map_file] [-n sym_file]\n"
" [-O overlay_file] [-o out_file] [-p pad_value]\n"
" [-S spec] [-s symbol] <file> ...\n"
"Useful options:\n"
" -l, --linkerscript <path> set the input linker script\n"
" -m, --map <path> set the output map file\n"
" -n, --sym <path> set the output symbol list file\n"
" -o, --output <path> set the output file\n"
" -p, --pad <value> set the value to pad between sections with\n"
" -x, --nopad disable padding of output binary\n"
" -V, --version print RGBLINK version and exits\n"
"\n"
"For help, use `man rgblink' or go to https://rgbds.gbdev.io/docs/\n",
stderr);
}
// Cleans up what has been done
// Mostly here to please tools such as `valgrind` so actual errors can be seen
static void cleanup(void)
{
obj_Cleanup();
}
enum ScrambledRegion {
SCRAMBLE_ROMX,
SCRAMBLE_SRAM,
SCRAMBLE_WRAMX,
SCRAMBLE_UNK, // Used for errors
};
struct {
char const *name;
uint16_t max;
} scrambleSpecs[SCRAMBLE_UNK] = {
[SCRAMBLE_ROMX] = { "romx", 65535 },
[SCRAMBLE_SRAM] = { "sram", 255 },
[SCRAMBLE_WRAMX] = { "wramx", 7},
};
static void parseScrambleSpec(char const *spec)
{
// Skip any leading whitespace
spec += strspn(spec, " \t");
// The argument to `-S` should be a comma-separated list of sections followed by an '='
// indicating their scramble limit.
while (spec) {
// Invariant: we should not be pointing at whitespace at this point
assert(*spec != ' ' && *spec != '\t');
// Remember where the region's name begins and ends
char const *regionName = spec;
size_t regionNameLen = strcspn(spec, "=, \t");
// Length of region name string slice for printing, truncated if too long
int regionNamePrintLen = regionNameLen > INT_MAX ? INT_MAX : (int)regionNameLen;
// If this trips, `spec` must be pointing at a ',' or '=' (or NUL) due to the assert
if (regionNameLen == 0) {
argErr('S', "Missing region name");
if (*spec == '\0')
break;
if (*spec == '=') // Skip the limit, too
spec = strchr(&spec[1], ','); // Skip to next comma, if any
goto next;
}
// Find the next non-blank char after the region name's end
spec += regionNameLen + strspn(&spec[regionNameLen], " \t");
if (*spec != '\0' && *spec != ',' && *spec != '=') {
argErr('S', "Unexpected '%c' after region name \"%.*s\"",
regionNamePrintLen, regionName);
// Skip to next ',' or '=' (or NUL) and keep parsing
spec += 1 + strcspn(&spec[1], ",=");
}
// Now, determine which region type this is
enum ScrambledRegion region = 0;
for (; region < SCRAMBLE_UNK; region++) {
// If the strings match (case-insensitively), we got it!
// `strncasecmp` must be used here since `regionName` points
// to the entire remaining argument.
if (!strncasecmp(scrambleSpecs[region].name, regionName, regionNameLen))
break;
}
if (region == SCRAMBLE_UNK)
argErr('S', "Unknown region \"%.*s\"", regionNamePrintLen, regionName);
if (*spec == '=') {
spec++; // `strtoul` will skip the whitespace on its own
unsigned long limit;
char *endptr;
if (*spec == '\0' || *spec == ',') {
argErr('S', "Empty limit for region \"%.*s\"",
regionNamePrintLen, regionName);
goto next;
}
limit = strtoul(spec, &endptr, 10);
endptr += strspn(endptr, " \t");
if (*endptr != '\0' && *endptr != ',') {
argErr('S', "Invalid non-numeric limit for region \"%.*s\"",
regionNamePrintLen, regionName);
endptr = strchr(endptr, ',');
}
spec = endptr;
if (region != SCRAMBLE_UNK && limit >= scrambleSpecs[region].max) {
argErr('S', "Limit for region \"%.*s\" may not exceed %" PRIu16,
regionNamePrintLen, regionName, scrambleSpecs[region].max);
limit = scrambleSpecs[region].max;
}
switch (region) {
case SCRAMBLE_ROMX:
scrambleROMX = limit;
break;
case SCRAMBLE_SRAM:
scrambleSRAM = limit;
break;
case SCRAMBLE_WRAMX:
scrambleWRAMX = limit;
break;
case SCRAMBLE_UNK: // The error has already been reported, do nothing
break;
}
} else if (region == SCRAMBLE_WRAMX) {
// Only WRAMX can be implied, since ROMX and SRAM size may vary
scrambleWRAMX = 7;
} else {
argErr('S', "Cannot imply limit for region \"%.*s\"",
regionNamePrintLen, regionName);
}
next:
if (spec) {
assert(*spec == ',' || *spec == '\0');
if (*spec == ',')
spec += 1 + strspn(&spec[1], " \t");
if (*spec == '\0')
break;
}
}
}
_Noreturn void reportErrors(void) {
fprintf(stderr, "Linking failed with %" PRIu32 " error%s\n",
nbErrors, nbErrors == 1 ? "" : "s");
exit(1);
}
int main(int argc, char *argv[])
{
int optionChar;
char *endptr; // For error checking with `strtoul`
unsigned long value; // For storing `strtoul`'s return value
// Parse options
while ((optionChar = musl_getopt_long_only(argc, argv, optstring,
longopts, NULL)) != -1) {
switch (optionChar) {
case 'd':
isDmgMode = true;
isWRA0Mode = true;
break;
case 'l':
linkerScriptName = musl_optarg;
break;
case 'M':
noSymInMap = true;
break;
case 'm':
mapFileName = musl_optarg;
break;
case 'n':
symFileName = musl_optarg;
break;
case 'O':
overlayFileName = musl_optarg;
break;
case 'o':
outputFileName = musl_optarg;
break;
case 'p':
value = strtoul(musl_optarg, &endptr, 0);
if (musl_optarg[0] == '\0' || *endptr != '\0') {
argErr('p', "");
value = 0xFF;
}
if (value > 0xFF) {
argErr('p', "Argument for 'p' must be a byte (between 0 and 0xFF)");
value = 0xFF;
}
padValue = value;
break;
case 'S':
parseScrambleSpec(musl_optarg);
break;
case 's':
// FIXME: nobody knows what this does, figure it out
(void)musl_optarg;
warning(NULL, 0, "Nobody has any idea what `-s` does");
break;
case 't':
is32kMode = true;
break;
case 'V':
printf("rgblink %s\n", get_package_version_string());
exit(0);
case 'v':
beVerbose = true;
break;
case 'w':
isWRA0Mode = true;
break;
case 'x':
disablePadding = true;
// implies tiny mode
is32kMode = true;
break;
default:
printUsage();
exit(1);
}
}
int curArgIndex = musl_optind;
// If no input files were specified, the user must have screwed up
if (curArgIndex == argc) {
fputs("FATAL: no input files\n", stderr);
printUsage();
exit(1);
}
// Patch the size array depending on command-line options
if (!is32kMode)
sectionTypeInfo[SECTTYPE_ROM0].size = 0x4000;
if (!isWRA0Mode)
sectionTypeInfo[SECTTYPE_WRAM0].size = 0x1000;
// Patch the bank ranges array depending on command-line options
if (isDmgMode)
sectionTypeInfo[SECTTYPE_VRAM].lastBank = 0;
// Read all object files first,
for (obj_Setup(argc - curArgIndex); curArgIndex < argc; curArgIndex++)
obj_ReadFile(argv[curArgIndex], argc - curArgIndex - 1);
// apply the linker script's modifications,
if (linkerScriptName) {
verbosePrint("Reading linker script...\n");
linkerScript = openFile(linkerScriptName, "r");
// Modify all sections according to the linker script
struct SectionPlacement *placement;
while ((placement = script_NextSection())) {
struct Section *section = placement->section;
assert(section->offset == 0);
// Check if this doesn't conflict with what the code says
if (section->type == SECTTYPE_INVALID) {
for (struct Section *sect = section; sect; sect = sect->nextu)
sect->type = placement->type; // SDCC "unknown" sections
} else if (section->type != placement->type) {
error(NULL, 0, "Linker script contradicts \"%s\"'s type",
section->name);
}
if (section->isBankFixed && placement->bank != section->bank)
error(NULL, 0, "Linker script contradicts \"%s\"'s bank placement",
section->name);
if (section->isAddressFixed && placement->org != section->org)
error(NULL, 0, "Linker script contradicts \"%s\"'s address placement",
section->name);
if (section->isAlignFixed
&& (placement->org & section->alignMask) != 0)
error(NULL, 0, "Linker script contradicts \"%s\"'s alignment",
section->name);
section->isAddressFixed = true;
section->org = placement->org;
section->isBankFixed = true;
section->bank = placement->bank;
section->isAlignFixed = false; // The alignment is satisfied
}
fclose(linkerScript);
script_Cleanup();
// If the linker script produced any errors, some sections may be in an invalid state
if (nbErrors != 0)
reportErrors();
}
// then process them,
obj_DoSanityChecks();
if (nbErrors != 0)
reportErrors();
assign_AssignSections();
obj_CheckAssertions();
assign_Cleanup();
// and finally output the result.
patch_ApplyPatches();
if (nbErrors != 0)
reportErrors();
out_WriteFiles();
// Do cleanup before quitting, though.
cleanup();
}