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main.cc
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main.cc
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#include "mold.h"
#include <functional>
#include <map>
#include <signal.h>
#include <tbb/global_control.h>
#include <tbb/parallel_do.h>
#include <tbb/parallel_for_each.h>
#include <tbb/task_group.h>
#include <unordered_set>
static tbb::task_group parser_tg;
static bool preloading;
static bool is_text_file(MemoryMappedFile *mb) {
return mb->size() >= 4 &&
isprint(mb->data()[0]) &&
isprint(mb->data()[1]) &&
isprint(mb->data()[2]) &&
isprint(mb->data()[3]);
}
enum class FileType { UNKNOWN, OBJ, DSO, AR, THIN_AR, TEXT };
static FileType get_file_type(MemoryMappedFile *mb) {
if (mb->size() >= 20 && memcmp(mb->data(), "\177ELF", 4) == 0) {
ElfEhdr &ehdr = *(ElfEhdr *)mb->data();
if (ehdr.e_type == ET_REL)
return FileType::OBJ;
if (ehdr.e_type == ET_DYN)
return FileType::DSO;
return FileType::UNKNOWN;
}
if (mb->size() >= 8 && memcmp(mb->data(), "!<arch>\n", 8) == 0)
return FileType::AR;
if (mb->size() >= 8 && memcmp(mb->data(), "!<thin>\n", 8) == 0)
return FileType::THIN_AR;
if (is_text_file(mb))
return FileType::TEXT;
return FileType::UNKNOWN;
}
static ObjectFile *new_object_file(MemoryMappedFile *mb,
std::string archive_name,
ReadContext &ctx) {
bool in_lib = (!archive_name.empty() && !ctx.whole_archive);
ObjectFile *file = new ObjectFile(mb, archive_name, in_lib);
parser_tg.run([=]() { file->parse(); });
return file;
}
static SharedFile *new_shared_file(MemoryMappedFile *mb, bool as_needed) {
SharedFile *file = new SharedFile(mb, as_needed);
parser_tg.run([=]() { file->parse(); });
return file;
}
template <typename T>
class FileCache {
public:
void store(MemoryMappedFile *mb, T *obj) {
Key k(mb->name, mb->size(), mb->mtime);
cache[k].push_back(obj);
}
std::vector<T *> get(MemoryMappedFile *mb) {
Key k(mb->name, mb->size(), mb->mtime);
std::vector<T *> objs = cache[k];
cache[k].clear();
return objs;
}
T *get_one(MemoryMappedFile *mb) {
std::vector<T *> objs = get(mb);
return objs.empty() ? nullptr : objs[0];
}
private:
typedef std::tuple<std::string, i64, i64> Key;
std::map<Key, std::vector<T *>> cache;
};
void read_file(MemoryMappedFile *mb, ReadContext &ctx) {
static FileCache<ObjectFile> obj_cache;
static FileCache<SharedFile> dso_cache;
if (preloading) {
switch (get_file_type(mb)) {
case FileType::OBJ:
obj_cache.store(mb, new_object_file(mb, "", ctx));
return;
case FileType::DSO:
dso_cache.store(mb, new_shared_file(mb, ctx.as_needed));
return;
case FileType::AR:
for (MemoryMappedFile *child : read_fat_archive_members(mb))
obj_cache.store(mb, new_object_file(child, mb->name, ctx));
return;
case FileType::THIN_AR:
for (MemoryMappedFile *child : read_thin_archive_members(mb))
obj_cache.store(child, new_object_file(child, mb->name, ctx));
return;
case FileType::TEXT:
parse_linker_script(mb, ctx);
return;
}
Fatal() << mb->name << ": unknown file type";
}
switch (get_file_type(mb)) {
case FileType::OBJ:
if (ObjectFile *obj = obj_cache.get_one(mb))
out::objs.push_back(obj);
else
out::objs.push_back(new_object_file(mb, "", ctx));
return;
case FileType::DSO:
if (SharedFile *obj = dso_cache.get_one(mb))
out::dsos.push_back(obj);
else
out::dsos.push_back(new_shared_file(mb, ctx.as_needed));
return;
case FileType::AR:
if (std::vector<ObjectFile *> objs = obj_cache.get(mb); !objs.empty()) {
append(out::objs, objs);
} else {
for (MemoryMappedFile *child : read_archive_members(mb))
out::objs.push_back(new_object_file(child, mb->name, ctx));
}
return;
case FileType::THIN_AR:
for (MemoryMappedFile *child : read_thin_archive_members(mb)) {
if (ObjectFile *obj = obj_cache.get_one(child))
out::objs.push_back(obj);
else
out::objs.push_back(new_object_file(child, mb->name, ctx));
}
return;
case FileType::TEXT:
parse_linker_script(mb, ctx);
return;
}
Fatal() << mb->name << ": unknown file type";
}
template <typename T>
static std::vector<std::span<T>> split(std::vector<T> &input, i64 unit) {
assert(input.size() > 0);
std::span<T> span(input);
std::vector<std::span<T>> vec;
while (span.size() >= unit) {
vec.push_back(span.subspan(0, unit));
span = span.subspan(unit);
}
if (!span.empty())
vec.push_back(span);
return vec;
}
static void resolve_symbols() {
Timer t("resolve_symbols");
// Register defined symbols
tbb::parallel_for_each(out::objs, [](ObjectFile *file) {
file->resolve_symbols();
});
tbb::parallel_for_each(out::dsos, [](SharedFile *file) {
file->resolve_symbols();
});
// Mark reachable objects and DSOs to decide which files to include
// into an output.
std::vector<ObjectFile *> roots;
for (ObjectFile *file : out::objs)
if (file->is_alive)
roots.push_back(file);
for (std::string_view name : config.undefined)
if (InputFile *file = Symbol::intern(name)->file)
if (!file->is_alive.exchange(true) && !file->is_dso)
roots.push_back((ObjectFile *)file);
tbb::parallel_do(roots,
[&](ObjectFile *file,
tbb::parallel_do_feeder<ObjectFile *> &feeder) {
file->mark_live_objects(
[&](ObjectFile *obj) { feeder.add(obj); });
});
// Eliminate unused archive members and as-needed DSOs.
erase(out::objs, [](InputFile *file) { return !file->is_alive; });
erase(out::dsos, [](InputFile *file) { return !file->is_alive; });
}
static void eliminate_comdats() {
Timer t("comdat");
tbb::parallel_for_each(out::objs, [](ObjectFile *file) {
file->resolve_comdat_groups();
});
tbb::parallel_for_each(out::objs, [](ObjectFile *file) {
file->eliminate_duplicate_comdat_groups();
});
}
static void handle_mergeable_strings() {
Timer t("resolve_strings");
// Resolve mergeable string fragments
tbb::parallel_for_each(out::objs, [](ObjectFile *file) {
for (MergeableSection *isec : file->mergeable_sections) {
for (SectionFragment *frag : isec->fragments) {
if (!frag->is_alive)
continue;
MergeableSection *cur = frag->isec;
while (!cur || cur->file->priority > isec->file->priority)
if (frag->isec.compare_exchange_weak(cur, isec))
break;
}
}
});
// Calculate the total bytes of mergeable strings for each input section.
tbb::parallel_for_each(out::objs, [](ObjectFile *file) {
for (MergeableSection *isec : file->mergeable_sections) {
i64 offset = 0;
for (SectionFragment *frag : isec->fragments) {
if (frag->isec == isec && frag->offset == -1) {
offset = align_to(offset, frag->alignment);
frag->offset = offset;
offset += frag->data.size();
}
}
isec->size = offset;
}
});
// Assign each mergeable input section a unique index.
for (ObjectFile *file : out::objs) {
for (MergeableSection *isec : file->mergeable_sections) {
i64 offset = isec->parent.shdr.sh_size;
i64 alignment = isec->shdr.sh_addralign;
isec->padding = align_to(offset, alignment) - offset;
isec->offset = offset + isec->padding;
isec->parent.shdr.sh_size = offset + isec->padding + isec->size;
isec->parent.shdr.sh_addralign =
std::max(isec->parent.shdr.sh_addralign, isec->shdr.sh_addralign);
}
}
}
// So far, each input section has a pointer to its corresponding
// output section, but there's no reverse edge to get a list of
// input sections from an output section. This function creates it.
//
// An output section may contain millions of input sections.
// So, we append input sections to output sections in parallel.
static void bin_sections() {
Timer t("bin_sections");
i64 unit = (out::objs.size() + 127) / 128;
std::vector<std::span<ObjectFile *>> slices = split(out::objs, unit);
i64 num_osec = OutputSection::instances.size();
std::vector<std::vector<std::vector<InputSection *>>> groups(slices.size());
for (i64 i = 0; i < groups.size(); i++)
groups[i].resize(num_osec);
tbb::parallel_for((i64)0, (i64)slices.size(), [&](i64 i) {
for (ObjectFile *file : slices[i])
for (InputSection *isec : file->sections)
if (isec)
groups[i][isec->output_section->idx].push_back(isec);
});
std::vector<i64> sizes(num_osec);
for (std::span<std::vector<InputSection *>> group : groups)
for (i64 i = 0; i < group.size(); i++)
sizes[i] += group[i].size();
tbb::parallel_for((i64)0, num_osec, [&](i64 j) {
OutputSection::instances[j]->members.reserve(sizes[j]);
for (i64 i = 0; i < groups.size(); i++)
append(OutputSection::instances[j]->members, groups[i][j]);
});
}
static void check_duplicate_symbols() {
Timer t("check_dup_syms");
tbb::parallel_for_each(out::objs, [&](ObjectFile *file) {
for (i64 i = file->first_global; i < file->elf_syms.size(); i++) {
const ElfSym &esym = file->elf_syms[i];
Symbol &sym = *file->symbols[i];
bool is_weak = (esym.st_bind == STB_WEAK);
bool is_eliminated =
!esym.is_abs() && !esym.is_common() && !file->sections[esym.st_shndx];
if (esym.is_defined() && !is_weak && !is_eliminated && sym.file != file)
Error() << "duplicate symbol: " << *file << ": " << *sym.file
<< ": " << sym.name;
}
});
Error::checkpoint();
}
static void set_isec_offsets() {
Timer t("isec_offsets");
tbb::parallel_for_each(OutputSection::instances, [&](OutputSection *osec) {
if (osec->members.empty())
return;
std::vector<std::span<InputSection *>> slices = split(osec->members, 10000);
std::vector<i64> size(slices.size());
std::vector<i64> alignments(slices.size());
tbb::parallel_for((i64)0, (i64)slices.size(), [&](i64 i) {
i64 off = 0;
i64 align = 1;
for (InputChunk *isec : slices[i]) {
off = align_to(off, isec->shdr.sh_addralign);
isec->offset = off;
off += isec->shdr.sh_size;
align = std::max<i64>(align, isec->shdr.sh_addralign);
}
size[i] = off;
alignments[i] = align;
});
i64 align = *std::max_element(alignments.begin(), alignments.end());
std::vector<i64> start(slices.size());
for (i64 i = 1; i < slices.size(); i++)
start[i] = align_to(start[i - 1] + size[i - 1], align);
tbb::parallel_for((i64)1, (i64)slices.size(), [&](i64 i) {
for (InputChunk *isec : slices[i])
isec->offset += start[i];
});
osec->shdr.sh_size = start.back() + size.back();
osec->shdr.sh_addralign = align;
});
}
static void scan_rels() {
Timer t("scan_rels");
// Scan relocations to find dynamic symbols.
tbb::parallel_for_each(out::objs, [&](ObjectFile *file) {
file->scan_relocations();
});
// Exit if there was a relocation that refers an undefined symbol.
Error::checkpoint();
// Export symbols referenced by DSOs.
tbb::parallel_for_each(out::dsos, [&](SharedFile *file) {
for (Symbol *sym : file->undefs)
if (sym->file && !sym->file->is_dso)
sym->flags |= NEEDS_DYNSYM;
});
// Aggregate dynamic symbols to a single vector.
std::vector<InputFile *> files;
append(files, out::objs);
append(files, out::dsos);
std::vector<std::vector<Symbol *>> vec(files.size());
tbb::parallel_for((i64)0, (i64)files.size(), [&](i64 i) {
for (Symbol *sym : files[i]->symbols)
if (sym->flags && sym->file == files[i])
vec[i].push_back(sym);
});
// Assign offsets in additional tables for each dynamic symbol.
for (Symbol *sym : flatten(vec)) {
if (sym->is_imported() || (sym->flags & NEEDS_DYNSYM))
out::dynsym->add_symbol(sym);
if (sym->flags & NEEDS_GOT)
out::got->add_got_symbol(sym);
if (sym->flags & NEEDS_PLT) {
if (sym->flags & NEEDS_GOT)
out::pltgot->add_symbol(sym);
else
out::plt->add_symbol(sym);
}
if (sym->flags & NEEDS_GOTTPOFF)
out::got->add_gottpoff_symbol(sym);
if (sym->flags & NEEDS_TLSGD)
out::got->add_tlsgd_symbol(sym);
if (sym->flags & NEEDS_TLSLD)
out::got->add_tlsld();
if (sym->flags & NEEDS_COPYREL) {
out::copyrel->add_symbol(sym);
assert(sym->file->is_dso);
for (Symbol *alias : ((SharedFile *)sym->file)->find_aliases(sym)) {
alias->has_copyrel = true;
alias->value = sym->value;
out::dynsym->add_symbol(alias);
}
}
}
}
static void export_dynamic() {
Timer t("export_dynamic");
if (config.export_dynamic || config.shared) {
tbb::parallel_for((i64)0, (i64)out::objs.size(), [&](i64 i) {
ObjectFile *file = out::objs[i];
for (Symbol *sym : std::span(file->symbols).subspan(file->first_global))
if (sym->file == file && sym->esym->st_visibility == STV_DEFAULT)
sym->ver_idx = VER_NDX_GLOBAL;
});
}
for (std::string_view name : config.globals)
Symbol::intern(name)->ver_idx = VER_NDX_GLOBAL;
std::vector<std::vector<Symbol *>> vec(out::objs.size());
tbb::parallel_for((i64)0, (i64)out::objs.size(), [&](i64 i) {
ObjectFile *file = out::objs[i];
for (Symbol *sym : std::span(file->symbols).subspan(file->first_global))
if (sym->file == file && sym->ver_idx != VER_NDX_LOCAL)
vec[i].push_back(sym);
});
for (Symbol *sym : flatten(vec))
out::dynsym->add_symbol(sym);
}
static void fill_symbol_versions() {
Timer t("fill_symbol_versions");
// Create a list of versioned symbols and sort by file and version.
std::vector<Symbol *> syms(out::dynsym->symbols.begin() + 1,
out::dynsym->symbols.end());
erase(syms, [](Symbol *sym){ return sym->ver_idx < 2; });
if (syms.empty())
return;
sort(syms, [](Symbol *a, Symbol *b) {
return std::tuple(((SharedFile *)a->file)->soname, a->ver_idx) <
std::tuple(((SharedFile *)b->file)->soname, b->ver_idx);
});
// Compute sizes of .gnu.version and .gnu.version_r sections.
out::versym->contents.resize(out::dynsym->symbols.size(), 1);
out::versym->contents[0] = 0;
i64 sz = sizeof(ElfVerneed) + sizeof(ElfVernaux);
for (i64 i = 1; i < syms.size(); i++) {
if (syms[i - 1]->file != syms[i]->file)
sz += sizeof(ElfVerneed) + sizeof(ElfVernaux);
else if (syms[i - 1]->ver_idx != syms[i]->ver_idx)
sz += sizeof(ElfVernaux);
}
out::verneed->contents.resize(sz);
// Fill .gnu.versoin_r.
u8 *buf = (u8 *)&out::verneed->contents[0];
u16 version = 1;
ElfVerneed *verneed = nullptr;
ElfVernaux *aux = nullptr;
auto add_aux = [&](Symbol *sym) {
SharedFile *file = (SharedFile *)sym->file;
std::string_view verstr = file->version_strings[sym->ver_idx];
verneed->vn_cnt++;
if (aux)
aux->vna_next = sizeof(ElfVernaux);
aux = (ElfVernaux *)buf;
buf += sizeof(*aux);
aux->vna_hash = elf_hash(verstr);
aux->vna_other = ++version;
aux->vna_name = out::dynstr->add_string(verstr);
};
auto add_verneed = [&](Symbol *sym) {
SharedFile *file = (SharedFile *)sym->file;
out::verneed->shdr.sh_info++;
if (verneed)
verneed->vn_next = buf - (u8 *)verneed;
verneed = (ElfVerneed *)buf;
buf += sizeof(*verneed);
verneed->vn_version = 1;
verneed->vn_file = out::dynstr->find_string(file->soname);
verneed->vn_aux = sizeof(ElfVerneed);
aux = nullptr;
add_aux(sym);
};
add_verneed(syms[0]);
out::versym->contents[syms[0]->dynsym_idx] = version;
for (i64 i = 1; i < syms.size(); i++) {
if (syms[i - 1]->file != syms[i]->file)
add_verneed(syms[i]);
else if (syms[i - 1]->ver_idx != syms[i]->ver_idx)
add_aux(syms[i]);
out::versym->contents[syms[i]->dynsym_idx] = version;
}
}
static void clear_padding(i64 filesize) {
Timer t("clear_padding");
auto zero = [](OutputChunk *chunk, i64 next_start) {
i64 pos = chunk->shdr.sh_offset;
if (chunk->shdr.sh_type != SHT_NOBITS)
pos += chunk->shdr.sh_size;
memset(out::buf + pos, 0, next_start - pos);
};
for (i64 i = 1; i < out::chunks.size(); i++)
zero(out::chunks[i - 1], out::chunks[i]->shdr.sh_offset);
zero(out::chunks.back(), filesize);
}
// We want to sort output sections in the following order.
//
// note
// alloc readonly data
// alloc readonly code
// alloc writable tdata
// alloc writable tbss
// alloc writable data
// alloc writable bss
// nonalloc
static i64 get_section_rank(const ElfShdr &shdr) {
bool note = shdr.sh_type == SHT_NOTE;
bool alloc = shdr.sh_flags & SHF_ALLOC;
bool writable = shdr.sh_flags & SHF_WRITE;
bool exec = shdr.sh_flags & SHF_EXECINSTR;
bool tls = shdr.sh_flags & SHF_TLS;
bool nobits = shdr.sh_type == SHT_NOBITS;
return (!note << 6) | (!alloc << 5) | (writable << 4) |
(exec << 3) | (!tls << 2) | nobits;
}
static i64 set_osec_offsets(std::span<OutputChunk *> chunks) {
Timer t("osec_offset");
i64 fileoff = 0;
i64 vaddr = config.image_base;
for (OutputChunk *chunk : chunks) {
if (chunk->starts_new_ptload)
vaddr = align_to(vaddr, PAGE_SIZE);
if (vaddr % PAGE_SIZE > fileoff % PAGE_SIZE)
fileoff += vaddr % PAGE_SIZE - fileoff % PAGE_SIZE;
else if (vaddr % PAGE_SIZE < fileoff % PAGE_SIZE)
fileoff = align_to(fileoff, PAGE_SIZE) + vaddr % PAGE_SIZE;
fileoff = align_to(fileoff, chunk->shdr.sh_addralign);
vaddr = align_to(vaddr, chunk->shdr.sh_addralign);
chunk->shdr.sh_offset = fileoff;
if (chunk->shdr.sh_flags & SHF_ALLOC)
chunk->shdr.sh_addr = vaddr;
bool is_bss = chunk->shdr.sh_type == SHT_NOBITS;
if (!is_bss)
fileoff += chunk->shdr.sh_size;
bool is_tbss = is_bss && (chunk->shdr.sh_flags & SHF_TLS);
if (!is_tbss)
vaddr += chunk->shdr.sh_size;
}
return fileoff;
}
static void fix_synthetic_symbols(std::span<OutputChunk *> chunks) {
auto start = [](Symbol *sym, OutputChunk *chunk) {
if (sym && chunk) {
sym->shndx = chunk->shndx;
sym->value = chunk->shdr.sh_addr;
}
};
auto stop = [](Symbol *sym, OutputChunk *chunk) {
if (sym && chunk) {
sym->shndx = chunk->shndx;
sym->value = chunk->shdr.sh_addr + chunk->shdr.sh_size;
}
};
// __bss_start
for (OutputChunk *chunk : chunks) {
if (chunk->kind == OutputChunk::REGULAR && chunk->name == ".bss") {
start(out::__bss_start, chunk);
break;
}
}
// __ehdr_start
for (OutputChunk *chunk : chunks) {
if (chunk->shndx == 1) {
out::__ehdr_start->shndx = 1;
out::__ehdr_start->value = out::ehdr->shdr.sh_addr;
break;
}
}
// __rela_iplt_start and __rela_iplt_end
start(out::__rela_iplt_start, out::relplt);
stop(out::__rela_iplt_end, out::relplt);
// __{init,fini}_array_{start,end}
for (OutputChunk *chunk : chunks) {
switch (chunk->shdr.sh_type) {
case SHT_INIT_ARRAY:
start(out::__init_array_start, chunk);
stop(out::__init_array_end, chunk);
break;
case SHT_FINI_ARRAY:
start(out::__fini_array_start, chunk);
stop(out::__fini_array_end, chunk);
break;
}
}
// _end, end, _etext, etext, _edata and edata
for (OutputChunk *chunk : chunks) {
if (chunk->kind == OutputChunk::HEADER)
continue;
if (chunk->shdr.sh_flags & SHF_ALLOC)
stop(out::_end, chunk);
if (chunk->shdr.sh_flags & SHF_EXECINSTR)
stop(out::_etext, chunk);
if (chunk->shdr.sh_type != SHT_NOBITS && chunk->shdr.sh_flags & SHF_ALLOC)
stop(out::_edata, chunk);
}
// _DYNAMIC
start(out::_DYNAMIC, out::dynamic);
// _GLOBAL_OFFSET_TABLE_
start(out::_GLOBAL_OFFSET_TABLE_, out::gotplt);
// __GNU_EH_FRAME_HDR
start(out::__GNU_EH_FRAME_HDR, out::eh_frame_hdr);
// __start_ and __stop_ symbols
for (OutputChunk *chunk : chunks) {
if (is_c_identifier(chunk->name)) {
start(Symbol::intern("__start_" + std::string(chunk->name)), chunk);
stop(Symbol::intern("__stop_" + std::string(chunk->name)), chunk);
}
}
}
void cleanup() {
if (OutputFile::tmpfile)
unlink(OutputFile::tmpfile);
if (socket_tmpfile)
unlink(socket_tmpfile);
}
static void signal_handler(int) {
cleanup();
_exit(1);
}
MemoryMappedFile *find_library(std::string name,
std::span<std::string_view> lib_paths) {
for (std::string_view dir : lib_paths) {
std::string root = dir.starts_with("/") ? config.sysroot : "";
std::string stem = root + std::string(dir) + "/lib" + name;
if (!config.is_static)
if (MemoryMappedFile *mb = MemoryMappedFile::open(stem + ".so"))
return mb;
if (MemoryMappedFile *mb = MemoryMappedFile::open(stem + ".a"))
return mb;
}
Fatal() << "library not found: " << name;
}
static std::vector<std::string> add_dashes(std::string name) {
std::vector<std::string> opts;
opts.push_back("-" + name);
if (!name.starts_with("o"))
opts.push_back("--" + name);
return opts;
}
static bool read_arg(std::span<std::string_view> &args, std::string_view &arg,
std::string name) {
if (name.size() == 1) {
if (args[0] == "-" + name) {
if (args.size() == 1)
Fatal() << "option -" << name << ": argument missing";
arg = args[1];
args = args.subspan(2);
return true;
}
if (args[0].starts_with("-" + name)) {
arg = args[0].substr(name.size() + 1);
args = args.subspan(1);
return true;
}
return false;
}
for (std::string opt : add_dashes(name)) {
if (args[0] == opt) {
if (args.size() == 1)
Fatal() << "option " << name << ": argument missing";
arg = args[1];
args = args.subspan(2);
return true;
}
if (args[0].starts_with(opt + "=")) {
arg = args[0].substr(opt.size() + 1);
args = args.subspan(1);
return true;
}
}
return false;
}
static bool read_flag(std::span<std::string_view> &args, std::string name) {
for (std::string opt : add_dashes(name)) {
if (args[0] == opt) {
args = args.subspan(1);
return true;
}
}
return false;
}
static bool read_z_flag(std::span<std::string_view> &args, std::string name) {
if (args.size() >= 2 && args[0] == "-z" && args[1] == name) {
args = args.subspan(2);
return true;
}
if (!args.empty() && args[0] == "-z" + name) {
args = args.subspan(1);
return true;
}
return false;
}
static i64 parse_hex(std::string opt, std::string_view value) {
if (!value.starts_with("0x") && !value.starts_with("0X"))
Fatal() << "option -" << opt << ": not a hexadecimal number";
value = value.substr(2);
if (value.find_first_not_of("0123456789abcdefABCDEF") != std::string_view::npos)
Fatal() << "option -" << opt << ": not a hexadecimal number";
return std::stol(std::string(value), nullptr, 16);
}
static i64 parse_number(std::string opt, std::string_view value) {
if (value.find_first_not_of("0123456789") != std::string_view::npos)
Fatal() << "option -" << opt << ": not a number";
return std::stol(std::string(value));
}
static std::vector<std::string_view> read_response_file(std::string_view path) {
std::vector<std::string_view> vec;
MemoryMappedFile *mb = MemoryMappedFile::must_open(std::string(path));
auto read_quoted = [&](i64 i, char quote) {
std::string *buf = new std::string;
while (i < mb->size() && mb->data()[i] != quote) {
if (mb->data()[i] == '\\') {
buf->append(1, mb->data()[i + 1]);
i += 2;
} else {
buf->append(1, mb->data()[i++]);
}
}
if (i >= mb->size())
Fatal() << path << ": premature end of input";
vec.push_back(std::string_view(*buf));
return i + 1;
};
auto read_unquoted = [&](i64 i) {
std::string *buf = new std::string;
while (i < mb->size() && !isspace(mb->data()[i]))
buf->append(1, mb->data()[i++]);
vec.push_back(std::string_view(*buf));
return i;
};
for (i64 i = 0; i < mb->size();) {
if (isspace(mb->data()[i]))
i++;
else if (mb->data()[i] == '\'')
i = read_quoted(i + 1, '\'');
else if (mb->data()[i] == '\"')
i = read_quoted(i + 1, '\"');
else
i = read_unquoted(i);
}
return vec;
}
static std::vector<std::string_view> expand_response_files(char **argv) {
std::vector<std::string_view> vec;
for (i64 i = 0; argv[i]; i++) {
if (argv[i][0] == '@')
append(vec, read_response_file(argv[i] + 1));
else
vec.push_back(argv[i]);
}
return vec;
}
static std::vector<std::string_view> get_input_files(std::span<std::string_view> args) {
static std::unordered_set<std::string_view> needs_arg({
"o", "dynamic-linker", "export-dynamic", "e", "entry", "y",
"trace-symbol", "filler", "sysroot", "thread-count", "z",
"hash-style", "m", "rpath", "version-script",
});
std::vector<std::string_view> vec;
std::vector<std::string> library_paths;
while (args.empty()) {
if (needs_arg.contains(args[0])) {
if (args.size() == 1)
Fatal() << args[0] << ": missing argument";
args = args.subspan(2);
continue;
}
std::string_view arg;
if (read_arg(args, arg, "L") || read_arg(args, arg, "library-path")) {
library_paths.push_back(std::string(arg));
}
if (read_arg(args, arg, "l")) {
vec.push_back(arg);
continue;
}
if (args[0].starts_with("-")) {
args = args.subspan(1);
continue;
}
vec.push_back(args[0]);
args = args.subspan(1);
}
return vec;
}
static Config parse_nonpositional_args(std::span<std::string_view> args,
std::vector<std::string_view> &remaining) {
Config conf;
conf.thread_count =
tbb::global_control::active_value(tbb::global_control::max_allowed_parallelism);
while (!args.empty()) {
std::string_view arg;
if (read_arg(args, arg, "o")) {
conf.output = arg;
} else if (read_arg(args, arg, "dynamic-linker")) {
conf.dynamic_linker = arg;
} else if (read_flag(args, "export-dynamic")) {
conf.export_dynamic = true;
} else if (read_arg(args, arg, "e") || read_arg(args, arg, "entry")) {
conf.entry = arg;
} else if (read_flag(args, "print-map")) {
conf.print_map = true;
} else if (read_flag(args, "stats")) {
conf.stats = true;
} else if (read_flag(args, "static")) {
conf.is_static = true;
} else if (read_flag(args, "shared")) {
conf.shared = true;
} else if (read_arg(args, arg, "y") || read_arg(args, arg, "trace-symbol")) {
conf.trace_symbol.push_back(arg);
} else if (read_arg(args, arg, "filler")) {
conf.filler = parse_hex("filler", arg);
} else if (read_arg(args, arg, "L") || read_arg(args, arg, "library-path")) {
conf.library_paths.push_back(arg);
} else if (read_arg(args, arg, "sysroot")) {
conf.sysroot = arg;
} else if (read_arg(args, arg, "u") || read_arg(args, arg, "undefined")) {
conf.undefined.push_back(arg);
} else if (read_arg(args, arg, "hash-style")) {
if (arg == "sysv") {
conf.hash_style_sysv = true;
conf.hash_style_gnu = false;
} else if (arg == "gnu") {
conf.hash_style_sysv = false;
conf.hash_style_gnu = true;
} else if (arg == "both") {
conf.hash_style_sysv = true;
conf.hash_style_gnu = true;
} else {
Fatal() << "invalid --hash-style argument: " << arg;
}
} else if (read_flag(args, "allow-multiple-definition")) {
conf.allow_multiple_definition = true;
} else if (read_flag(args, "trace")) {
conf.trace = true;
} else if (read_flag(args, "eh-frame-hdr")) {
conf.eh_frame_hdr = true;
} else if (read_flag(args, "no-eh-frame-hdr")) {
conf.eh_frame_hdr = false;
} else if (read_flag(args, "pie") || read_flag(args, "pic-executable")) {
conf.pic = true;
conf.pie = true;
} else if (read_flag(args, "no-pie") || read_flag(args, "no-pic-executable")) {
conf.pic = false;
conf.pie = false;
} else if (read_flag(args, "relax")) {
conf.relax = true;
} else if (read_flag(args, "no-relax")) {
conf.relax = false;
} else if (read_flag(args, "perf")) {
conf.perf = true;
} else if (read_z_flag(args, "now")) {
conf.z_now = true;
} else if (read_flag(args, "fork")) {
conf.fork = true;
} else if (read_flag(args, "no-fork")) {
conf.fork = false;
} else if (read_flag(args, "gc-sections")) {
conf.gc_sections = true;
} else if (read_flag(args, "no-gc-sections")) {
conf.gc_sections = false;
} else if (read_flag(args, "print-gc-sections")) {
conf.print_gc_sections = true;
} else if (read_flag(args, "no-print-gc-sections")) {
conf.print_gc_sections = false;
} else if (read_flag(args, "icf")) {
conf.icf = true;
} else if (read_flag(args, "no-icf")) {
conf.icf = false;
} else if (read_flag(args, "print-icf-sections")) {
conf.print_icf_sections = true;
} else if (read_flag(args, "no-print-icf-sections")) {
conf.print_icf_sections = false;
} else if (read_flag(args, "quick-exit")) {
conf.quick_exit = true;
} else if (read_flag(args, "no-quick-exit")) {
conf.quick_exit = false;
} else if (read_arg(args, arg, "thread-count")) {
conf.thread_count = parse_number("thread-count", arg);
} else if (read_flag(args, "no-threads")) {
conf.thread_count = 1;
} else if (read_flag(args, "discard-all") || read_flag(args, "x")) {
conf.discard_all = true;
} else if (read_flag(args, "discard-locals") || read_flag(args, "X")) {
conf.discard_locals = true;
} else if (read_flag(args, "strip-all") || read_flag(args, "s")) {
conf.strip_all = true;
} else if (read_arg(args, arg, "rpath")) {
if (!conf.rpaths.empty())
conf.rpaths += ":";
conf.rpaths += arg;
} else if (read_arg(args, arg, "version-script")) {
conf.version_script.push_back(arg);
} else if (read_flag(args, "build-id")) {
conf.build_id = BuildIdKind::SHA256;
} else if (read_arg(args, arg, "build-id")) {
if (arg == "none")