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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
#include "SharedLibraries.h"
#include "platform.h"
#include "mozilla/Unused.h"
#include <AvailabilityMacros.h>
#include <dlfcn.h>
#include <mach-o/arch.h>
#include <mach-o/dyld_images.h>
#include <mach-o/dyld.h>
#include <mach-o/loader.h>
#include <mach/mach_init.h>
#include <mach/mach_traps.h>
#include <mach/task_info.h>
#include <mach/task.h>
#include <sstream>
#include <stdlib.h>
#include <string.h>
#include <vector>
// Architecture specific abstraction.
#if defined(GP_ARCH_x86)
typedef mach_header platform_mach_header;
typedef segment_command mach_segment_command_type;
# define MACHO_MAGIC_NUMBER MH_MAGIC
# define CMD_SEGMENT LC_SEGMENT
# define seg_size uint32_t
#else
typedef mach_header_64 platform_mach_header;
typedef segment_command_64 mach_segment_command_type;
# define MACHO_MAGIC_NUMBER MH_MAGIC_64
# define CMD_SEGMENT LC_SEGMENT_64
# define seg_size uint64_t
#endif
struct NativeSharedLibrary {
const platform_mach_header* header;
std::string path;
};
static std::vector<NativeSharedLibrary>* sSharedLibrariesList = nullptr;
class MOZ_RAII SharedLibrariesLock {
public:
SharedLibrariesLock() { sSharedLibrariesMutex.Lock(); }
~SharedLibrariesLock() { sSharedLibrariesMutex.Unlock(); }
SharedLibrariesLock(const SharedLibrariesLock&) = delete;
void operator=(const SharedLibrariesLock&) = delete;
private:
static mozilla::baseprofiler::detail::BaseProfilerMutex sSharedLibrariesMutex;
};
MOZ_RUNINIT mozilla::baseprofiler::detail::BaseProfilerMutex
SharedLibrariesLock::sSharedLibrariesMutex;
static void SharedLibraryAddImage(const struct mach_header* mh,
intptr_t vmaddr_slide) {
// NOTE: Presumably for backwards-compatibility reasons, this function accepts
// a mach_header even on 64-bit where it ought to be a mach_header_64. We cast
// it to the right type here.
auto header = reinterpret_cast<const platform_mach_header*>(mh);
Dl_info info;
if (!dladdr(header, &info)) {
return;
}
SharedLibrariesLock lock;
if (!sSharedLibrariesList) {
return;
}
NativeSharedLibrary lib = {header, info.dli_fname};
sSharedLibrariesList->push_back(lib);
}
static void SharedLibraryRemoveImage(const struct mach_header* mh,
intptr_t vmaddr_slide) {
// NOTE: Presumably for backwards-compatibility reasons, this function accepts
// a mach_header even on 64-bit where it ought to be a mach_header_64. We cast
// it to the right type here.
auto header = reinterpret_cast<const platform_mach_header*>(mh);
SharedLibrariesLock lock;
if (!sSharedLibrariesList) {
return;
}
uint32_t count = sSharedLibrariesList->size();
for (uint32_t i = 0; i < count; ++i) {
if ((*sSharedLibrariesList)[i].header == header) {
sSharedLibrariesList->erase(sSharedLibrariesList->begin() + i);
return;
}
}
}
void SharedLibraryInfo::Initialize() {
// NOTE: We intentionally leak this memory here. We're allocating dynamically
// in order to avoid static initializers.
sSharedLibrariesList = new std::vector<NativeSharedLibrary>();
_dyld_register_func_for_add_image(SharedLibraryAddImage);
_dyld_register_func_for_remove_image(SharedLibraryRemoveImage);
}
static void addSharedLibrary(const platform_mach_header* header,
const char* path, SharedLibraryInfo& info) {
const struct load_command* cmd =
reinterpret_cast<const struct load_command*>(header + 1);
seg_size size = 0;
unsigned long long start = reinterpret_cast<unsigned long long>(header);
// Find the cmd segment in the macho image. It will contain the offset we care
// about.
const uint8_t* uuid_bytes = nullptr;
for (unsigned int i = 0;
cmd && (i < header->ncmds) && (uuid_bytes == nullptr || size == 0);
++i) {
if (cmd->cmd == CMD_SEGMENT) {
const mach_segment_command_type* seg =
reinterpret_cast<const mach_segment_command_type*>(cmd);
if (!strcmp(seg->segname, "__TEXT")) {
size = seg->vmsize;
}
} else if (cmd->cmd == LC_UUID) {
const uuid_command* ucmd = reinterpret_cast<const uuid_command*>(cmd);
uuid_bytes = ucmd->uuid;
}
cmd = reinterpret_cast<const struct load_command*>(
reinterpret_cast<const char*>(cmd) + cmd->cmdsize);
}
std::string uuid;
std::string breakpadId;
if (uuid_bytes != nullptr) {
static constexpr char digits[16] = {'0', '1', '2', '3', '4', '5', '6', '7',
'8', '9', 'A', 'B', 'C', 'D', 'E', 'F'};
for (int i = 0; i < 16; ++i) {
uint8_t byte = uuid_bytes[i];
uuid += digits[byte >> 4];
uuid += digits[byte & 0xFu];
}
// Breakpad id is the same as the uuid but with the additional trailing 0
// for the breakpad id age.
breakpadId = uuid;
// breakpad id age.
breakpadId += '0';
}
std::string pathStr = path;
size_t pos = pathStr.rfind('/');
std::string nameStr =
(pos != std::string::npos) ? pathStr.substr(pos + 1) : pathStr;
const NXArchInfo* archInfo =
NXGetArchInfoFromCpuType(header->cputype, header->cpusubtype);
info.AddSharedLibrary(SharedLibrary(
start, start + size, 0, breakpadId, uuid, nameStr, pathStr, nameStr,
pathStr, std::string{}, archInfo ? archInfo->name : ""));
}
// Translate the statically stored sSharedLibrariesList information into a
// SharedLibraryInfo object.
SharedLibraryInfo SharedLibraryInfo::GetInfoForSelf() {
SharedLibrariesLock lock;
SharedLibraryInfo sharedLibraryInfo;
for (auto& info : *sSharedLibrariesList) {
addSharedLibrary(info.header, info.path.c_str(), sharedLibraryInfo);
}
// Add the entry for dyld itself.
// We only support macOS 10.12+, which corresponds to dyld version 15+.
// dyld version 15 added the dyldPath property.
task_dyld_info_data_t task_dyld_info;
mach_msg_type_number_t count = TASK_DYLD_INFO_COUNT;
if (task_info(mach_task_self(), TASK_DYLD_INFO, (task_info_t)&task_dyld_info,
&count) != KERN_SUCCESS) {
return sharedLibraryInfo;
}
struct dyld_all_image_infos* aii =
(struct dyld_all_image_infos*)task_dyld_info.all_image_info_addr;
if (aii->version >= 15) {
const platform_mach_header* header =
reinterpret_cast<const platform_mach_header*>(
aii->dyldImageLoadAddress);
addSharedLibrary(header, aii->dyldPath, sharedLibraryInfo);
}
return sharedLibraryInfo;
}