Atmosphere/libraries/libstratosphere/source/diag/impl/diag_symbol_impl.os.macos.cpp

319 lines
13 KiB
C++

/*
* Copyright (c) Atmosphère-NX
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <stratosphere.hpp>
#include "diag_symbol_impl.hpp"
#include <unistd.h>
#include <mach-o/dyld.h>
#include <mach-o/loader.h>
#include <mach-o/nlist.h>
#include <mach-o/stab.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <sys/param.h>
#include <sys/mman.h>
#include <cxxabi.h>
extern "C" {
void __module_offset_helper() { /* ... */ }
}
namespace ams::diag::impl {
namespace {
class CurrentExecutableHelper {
private:
struct SymbolInfo {
uintptr_t address;
const char *name;
};
private:
os::NativeHandle m_fd;
void *m_file_map;
size_t m_file_size;
SymbolInfo *m_symbols;
size_t m_num_symbol;
const char *m_module_name;
uintptr_t m_module_address;
size_t m_module_size;
uintptr_t m_module_displacement;
private:
CurrentExecutableHelper() : m_fd(-1), m_file_map(nullptr), m_file_size(0), m_symbols(nullptr), m_num_symbol(0), m_module_name(nullptr), m_module_address(0), m_module_size(0), m_module_displacement(0) {
/* Get the current executable name. */
char exe_path[4_KB] = {};
GetExecutablePath(exe_path, sizeof(exe_path));
/* Open the current executable. */
os::NativeHandle fd;
do {
fd = ::open(exe_path, O_RDONLY);
} while (fd < 0 && errno == EINTR);
if (fd < 0) {
return;
}
ON_SCOPE_EXIT { if (fd >= 0) { s32 ret; do { ret = ::close(fd); } while (ret < 0 && errno == EINTR); } };
/* Get the file size. */
struct stat st;
if (fstat(fd, std::addressof(st)) < 0) {
return;
}
/* Check that the file can be mapped. */
const size_t exe_size = st.st_size;
if (exe_size == 0) {
return;
}
/* Map the executable. */
void *exe_map = mmap(nullptr, exe_size, PROT_READ, MAP_PRIVATE, fd, 0);
if (exe_map == MAP_FAILED) {
return;
}
ON_SCOPE_EXIT { if (exe_map != nullptr) { munmap(exe_map, exe_size); } };
/* Get the file's u32 magic. */
const uintptr_t exe_start = reinterpret_cast<uintptr_t>(exe_map);
const u32 magic = *reinterpret_cast<const u32 *>(exe_start);
/* Get/parse the mach header. */
u32 ncmds;
bool is_64;
if (magic == MH_MAGIC) {
const auto *header = reinterpret_cast<const struct mach_header *>(exe_start);
ncmds = header->ncmds;
is_64 = false;
} else if (magic == MH_MAGIC_64) {
const auto *header = reinterpret_cast<const struct mach_header_64 *>(exe_start);
ncmds = header->ncmds;
is_64 = true;
} else {
return;
}
/* Find the symbol load command. */
const auto *lc = reinterpret_cast<const struct load_command *>(exe_start + (is_64 ? sizeof(struct mach_header_64) : sizeof(struct mach_header)));
for (u32 i = 0; i < ncmds; ++i) {
/* If we encounter the symbol table, parse it. */
if (lc->cmd == LC_SYMTAB) {
if (is_64) {
this->ParseSymbolTable<struct nlist_64>(exe_start, reinterpret_cast<const struct symtab_command *>(lc));
} else {
this->ParseSymbolTable<struct nlist>(exe_start, reinterpret_cast<const struct symtab_command *>(lc));
}
break;
} else if (lc->cmd == LC_SEGMENT) {
const auto *sc = reinterpret_cast<const struct segment_command *>(lc);
if (std::strcmp(sc->segname, "__TEXT") == 0) {
AMS_ASSERT(m_module_address == 0);
m_module_address = sc->vmaddr;
m_module_size = sc->vmsize;
AMS_ASSERT(m_module_address != 0);
}
} else if (lc->cmd == LC_SEGMENT_64) {
const auto *sc = reinterpret_cast<const struct segment_command_64 *>(lc);
if (std::strcmp(sc->segname, "__TEXT") == 0) {
AMS_ASSERT(m_module_address == 0);
m_module_address = sc->vmaddr;
m_module_size = sc->vmsize;
AMS_ASSERT(m_module_address != 0);
}
}
/* Advance to the next load command. */
lc = reinterpret_cast<const struct load_command *>(reinterpret_cast<uintptr_t>(lc) + lc->cmdsize);
}
for (size_t i = 0; i < m_num_symbol; ++i) {
if (std::strcmp(m_symbols[i].name, "___module_offset_helper") == 0) {
m_module_displacement = reinterpret_cast<uintptr_t>(&__module_offset_helper) - m_symbols[i].address;
break;
}
}
if (m_module_address > 0 && m_module_size > 0 && m_num_symbol > 0) {
std::swap(m_fd, fd);
std::swap(m_file_map, exe_map);
m_file_size = exe_size;
}
}
~CurrentExecutableHelper() {
if (m_file_map != nullptr) {
munmap(m_file_map, m_file_size);
}
if (m_fd >= 0) {
s32 ret;
do { ret = ::close(m_fd); } while (ret < 0 && errno == EINTR);
}
}
public:
static CurrentExecutableHelper &GetInstance() {
AMS_FUNCTION_LOCAL_STATIC(CurrentExecutableHelper, s_current_executable_helper_instance);
return s_current_executable_helper_instance;
}
private:
template<typename NlistType>
void ParseSymbolTable(uintptr_t exe_start, const struct symtab_command *c) {
/* Check pre-conditions. */
AMS_ASSERT(m_fd == -1);
AMS_ASSERT(m_file_map == nullptr);
AMS_ASSERT(m_symbols == nullptr);
/* Get the strtab/symtab. */
const auto *symtab = reinterpret_cast<const NlistType *>(exe_start + c->symoff);
const char *strtab = reinterpret_cast<const char *>(exe_start + c->stroff);
/* Determine the number of functions. */
size_t funcs = 0;
for (size_t i = 0; i < c->nsyms; ++i) {
if (symtab[i].n_type != N_FUN || symtab[i].n_sect == NO_SECT) {
continue;
}
++funcs;
}
/* Allocate functions. */
m_symbols = reinterpret_cast<SymbolInfo *>(std::malloc(sizeof(SymbolInfo) * funcs));
if (m_symbols == nullptr) {
return;
}
/* Set all symbols. */
m_num_symbol = 0;
for (size_t i = 0; i < c->nsyms; ++i) {
if (symtab[i].n_type != N_FUN || symtab[i].n_sect == NO_SECT) {
continue;
}
m_symbols[m_num_symbol].address = symtab[i].n_value;
m_symbols[m_num_symbol].name = strtab + symtab[i].n_un.n_strx;
++m_num_symbol;
}
AMS_ASSERT(m_num_symbol == funcs);
/* Sort the symbols. */
std::sort(m_symbols + 0, m_symbols + m_num_symbol, [] (const SymbolInfo &lhs, const SymbolInfo &rhs) {
return lhs.address < rhs.address;
});
}
size_t GetSymbolSizeImpl(const SymbolInfo *symbol) const {
/* Do our best to guess. */
if (symbol != m_symbols + m_num_symbol - 1) {
return (symbol + 1)->address - symbol->address;
} else if (m_module_address + m_module_size >= symbol->address) {
return m_module_address + m_module_size - symbol->address;
} else {
return 0;
}
}
const SymbolInfo *GetBestSymbol(uintptr_t address) const {
address -= m_module_displacement;
const SymbolInfo *best_symbol = std::lower_bound(m_symbols + 0, m_symbols + m_num_symbol, address, [](const SymbolInfo &lhs, uintptr_t rhs) {
return lhs.address < rhs;
});
if (best_symbol == m_symbols + m_num_symbol) {
return nullptr;
}
if (best_symbol->address != address && best_symbol > m_symbols) {
--best_symbol;
}
const auto vma = best_symbol->address;
const auto end = vma + this->GetSymbolSizeImpl(best_symbol);
if (vma <= address && address < end) {
return best_symbol;
} else {
return nullptr;
}
}
public:
uintptr_t GetSymbolName(char *dst, size_t dst_size, uintptr_t address) const {
if (m_fd < 0) {
return 0;
}
/* Get the symbol. */
const auto *symbol = this->GetBestSymbol(address);
if (symbol == nullptr) {
return 0;
}
/* Print the symbol. */
const char *name = symbol->name;
int cpp_name_status = 0;
if (char *demangled = abi::__cxa_demangle(name, nullptr, 0, std::addressof(cpp_name_status)); cpp_name_status == 0) {
AMS_ASSERT(demangled != nullptr);
util::TSNPrintf(dst, dst_size, "%s", demangled);
std::free(demangled);
} else {
util::TSNPrintf(dst, dst_size, "%s", name);
}
return symbol->address + m_module_displacement;
}
size_t GetSymbolSize(uintptr_t address) const {
if (m_fd < 0) {
return 0;
}
/* Get the symbol. */
const auto *symbol = this->GetBestSymbol(address);
if (symbol == nullptr) {
return 0;
}
return this->GetSymbolSizeImpl(symbol);
}
private:
static void GetExecutablePath(char *dst, size_t dst_size) {
u32 len = dst_size;
if (_NSGetExecutablePath(dst, std::addressof(len)) != 0) {
dst[0] = 0;
return;
}
}
};
}
uintptr_t GetSymbolNameImpl(char *dst, size_t dst_size, uintptr_t address) {
return CurrentExecutableHelper::GetInstance().GetSymbolName(dst, dst_size, address);
}
size_t GetSymbolSizeImpl(uintptr_t address) {
return CurrentExecutableHelper::GetInstance().GetSymbolSize(address);
}
}