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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* 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 "mozilla/Bootstrap.h"
#include "nsXPCOMPrivate.h"
#include <stdlib.h>
#include <stdio.h>
#include "mozilla/FileUtils.h"
#include "mozilla/ScopeExit.h"
#include "mozilla/Try.h"
#include "mozilla/UniquePtr.h"
#include "mozilla/UniquePtrExtensions.h"
#if defined(XP_WIN) && defined(_M_X64) && defined(MOZ_DIAGNOSTIC_ASSERT_ENABLED)
# include "mozilla/WindowsDiagnostics.h"
#endif // XP_WIN && _M_X64 && MOZ_DIAGNOSTIC_ASSERT_ENABLED
using namespace mozilla;
#define XPCOM_DEPENDENT_LIBS_LIST "dependentlibs.list"
#if defined(XP_WIN)
# define READ_TEXTMODE L"rt"
#else
# define READ_TEXTMODE "r"
#endif
typedef void (*NSFuncPtr)();
#if defined(XP_WIN)
# include <windows.h>
using LibHandleType = HMODULE;
#else
using LibHandleType = void*;
#endif
using LibHandleResult = ::mozilla::Result<LibHandleType, DLErrorType>;
#if defined(XP_WIN)
# include <mbstring.h>
# include "mozilla/PreXULSkeletonUI.h"
static LibHandleResult GetLibHandle(pathstr_t aDependentLib) {
LibHandleType libHandle =
LoadLibraryExW(aDependentLib, nullptr, LOAD_WITH_ALTERED_SEARCH_PATH);
if (!libHandle) {
DWORD err = GetLastError();
# if defined(DEBUG)
LPWSTR lpMsgBuf;
FormatMessageW(FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM |
FORMAT_MESSAGE_IGNORE_INSERTS,
nullptr, err, MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
(LPWSTR)&lpMsgBuf, 0, nullptr);
wprintf(L"Error loading %ls: %s\n", aDependentLib, lpMsgBuf);
LocalFree(lpMsgBuf);
# endif // defined(DEBUG)
return Err(err);
}
return libHandle;
}
static NSFuncPtr GetSymbol(LibHandleType aLibHandle, const char* aSymbol) {
return (NSFuncPtr)GetProcAddress(aLibHandle, aSymbol);
}
static void CloseLibHandle(LibHandleType aLibHandle) {
FreeLibrary(aLibHandle);
}
#else
# include <dlfcn.h>
# if defined(MOZ_LINKER)
extern "C" {
NS_HIDDEN __typeof(dlopen) __wrap_dlopen;
NS_HIDDEN __typeof(dlsym) __wrap_dlsym;
NS_HIDDEN __typeof(dlclose) __wrap_dlclose;
}
# define dlopen __wrap_dlopen
# define dlsym __wrap_dlsym
# define dlclose __wrap_dlclose
# endif
static LibHandleResult GetLibHandle(pathstr_t aDependentLib) {
LibHandleType libHandle = dlopen(aDependentLib, RTLD_GLOBAL | RTLD_LAZY
# ifdef XP_MACOSX
| RTLD_FIRST
# endif
);
if (!libHandle) {
UniqueFreePtr<char> errMsg(strdup(dlerror()));
fprintf(stderr, "XPCOMGlueLoad error for file %s:\n%s\n", aDependentLib,
errMsg.get());
return Err(std::move(errMsg));
}
return libHandle;
}
static NSFuncPtr GetSymbol(LibHandleType aLibHandle, const char* aSymbol) {
return (NSFuncPtr)dlsym(aLibHandle, aSymbol);
}
# if !defined(MOZ_LINKER) && !defined(__ANDROID__)
static void CloseLibHandle(LibHandleType aLibHandle) { dlclose(aLibHandle); }
# endif
#endif
struct DependentLib {
LibHandleType libHandle;
DependentLib* next;
};
static DependentLib* sTop;
static void AppendDependentLib(LibHandleType aLibHandle) {
auto* d = new DependentLib;
if (!d) {
return;
}
d->next = sTop;
d->libHandle = aLibHandle;
sTop = d;
}
using ReadDependentCBResult = ::mozilla::Result<::mozilla::Ok, DLErrorType>;
static ReadDependentCBResult ReadDependentCB(
pathstr_t aDependentLib, LibLoadingStrategy aLibLoadingStrategy) {
#if !defined(MOZ_LINKER) && !defined(__ANDROID__)
// Don't bother doing a ReadAhead if we're not in the parent process.
// What we need from the library should already be in the system file
// cache.
if (aLibLoadingStrategy == LibLoadingStrategy::ReadAhead) {
ReadAheadLib(aDependentLib);
}
#endif
LibHandleType libHandle;
MOZ_TRY_VAR(libHandle, GetLibHandle(aDependentLib));
AppendDependentLib(libHandle);
return Ok();
}
#ifdef XP_WIN
static ReadDependentCBResult ReadDependentCB(
const char* aDependentLib, LibLoadingStrategy aLibLoadingStrategy) {
wchar_t wideDependentLib[MAX_PATH];
MultiByteToWideChar(CP_UTF8, 0, aDependentLib, -1, wideDependentLib,
MAX_PATH);
return ReadDependentCB(wideDependentLib, aLibLoadingStrategy);
}
inline FILE* TS_tfopen(const char* path, const wchar_t* mode) {
wchar_t wPath[MAX_PATH];
MultiByteToWideChar(CP_UTF8, 0, path, -1, wPath, MAX_PATH);
return _wfopen(wPath, mode);
}
#else
inline FILE* TS_tfopen(const char* aPath, const char* aMode) {
return fopen(aPath, aMode);
}
#endif
#if !defined(MOZ_LINKER) && !defined(__ANDROID__)
static void XPCOMGlueUnload() {
while (sTop) {
CloseLibHandle(sTop->libHandle);
DependentLib* temp = sTop;
sTop = sTop->next;
delete temp;
}
}
#endif
#if defined(XP_WIN)
// like strpbrk but finds the *last* char, not the first
static const char* ns_strrpbrk(const char* string, const char* strCharSet) {
const char* found = nullptr;
for (; *string; ++string) {
for (const char* search = strCharSet; *search; ++search) {
if (*search == *string) {
found = string;
// Since we're looking for the last char, we save "found"
// until we're at the end of the string.
}
}
}
return found;
}
#endif
using XPCOMGlueLoadError = BootstrapError;
using XPCOMGlueLoadResult =
::mozilla::Result<::mozilla::Ok, XPCOMGlueLoadError>;
static XPCOMGlueLoadResult XPCOMGlueLoad(
const char* aXPCOMFile, LibLoadingStrategy aLibLoadingStrategy) {
#if defined(MOZ_LINKER) || defined(__ANDROID__)
ReadDependentCBResult readDependentCBResult =
ReadDependentCB(aXPCOMFile, aLibLoadingStrategy);
if (readDependentCBResult.isErr()) {
return Err(AsVariant(readDependentCBResult.unwrapErr()));
}
#else
char xpcomDir[MAXPATHLEN];
# ifdef XP_WIN
const char* lastSlash = ns_strrpbrk(aXPCOMFile, "/\\");
# elif XP_MACOSX
// On OSX, the dependentlibs.list file lives under Contents/Resources.
// However, the actual libraries listed in dependentlibs.list live under
// Contents/MacOS. We want to read the list from Contents/Resources, then
// load the libraries from Contents/MacOS.
const char* tempSlash = strrchr(aXPCOMFile, '/');
size_t tempLen = size_t(tempSlash - aXPCOMFile);
if (tempLen > MAXPATHLEN) {
return Err(AsVariant(NS_ERROR_FAILURE));
}
char tempBuffer[MAXPATHLEN];
memcpy(tempBuffer, aXPCOMFile, tempLen);
tempBuffer[tempLen] = '\0';
const char* slash = strrchr(tempBuffer, '/');
tempLen = size_t(slash - tempBuffer);
const char* lastSlash = aXPCOMFile + tempLen;
# else
const char* lastSlash = strrchr(aXPCOMFile, '/');
# endif
char* cursor;
if (lastSlash) {
size_t len = size_t(lastSlash - aXPCOMFile);
if (len > MAXPATHLEN - sizeof(XPCOM_FILE_PATH_SEPARATOR
# ifdef XP_MACOSX
"Resources" XPCOM_FILE_PATH_SEPARATOR
# endif
XPCOM_DEPENDENT_LIBS_LIST)) {
return Err(AsVariant(NS_ERROR_FAILURE));
}
memcpy(xpcomDir, aXPCOMFile, len);
strcpy(xpcomDir + len, XPCOM_FILE_PATH_SEPARATOR
# ifdef XP_MACOSX
"Resources" XPCOM_FILE_PATH_SEPARATOR
# endif
XPCOM_DEPENDENT_LIBS_LIST);
cursor = xpcomDir + len + 1;
} else {
strcpy(xpcomDir, XPCOM_DEPENDENT_LIBS_LIST);
cursor = xpcomDir;
}
if (getenv("MOZ_RUN_GTEST")
# ifdef FUZZING
|| getenv("FUZZER")
# endif
) {
strcat(xpcomDir, ".gtest");
}
const auto flist = TS_tfopen(xpcomDir, READ_TEXTMODE);
const auto cleanup = MakeScopeExit([&]() {
if (flist) {
fclose(flist);
}
});
if (!flist) {
return Err(AsVariant(NS_ERROR_FAILURE));
}
# ifdef XP_MACOSX
tempLen = size_t(cursor - xpcomDir);
if (tempLen > MAXPATHLEN - sizeof("MacOS" XPCOM_FILE_PATH_SEPARATOR) - 1) {
return Err(AsVariant(NS_ERROR_FAILURE));
}
strcpy(cursor, "MacOS" XPCOM_FILE_PATH_SEPARATOR);
cursor += strlen(cursor);
# endif
*cursor = '\0';
char buffer[MAXPATHLEN];
while (fgets(buffer, sizeof(buffer), flist)) {
int l = strlen(buffer);
// ignore empty lines and comments
if (l == 0 || *buffer == '#') {
continue;
}
// cut the trailing newline, if present
if (buffer[l - 1] == '\n') {
buffer[l - 1] = '\0';
}
if (l + size_t(cursor - xpcomDir) > MAXPATHLEN) {
return Err(AsVariant(NS_ERROR_FAILURE));
}
strcpy(cursor, buffer);
ReadDependentCBResult readDependentCBResult =
ReadDependentCB(xpcomDir, aLibLoadingStrategy);
if (readDependentCBResult.isErr()) {
XPCOMGlueUnload();
return Err(AsVariant(readDependentCBResult.unwrapErr()));
}
# ifdef XP_WIN
// We call PollPreXULSkeletonUIEvents here in order to not get flagged by
// Windows as nonresponsive. In order to not be flagged as such, we seem to
// simply need to respond to *a* message every few seconds. The halfway
// point on slow systems between process start and nsWindow taking over the
// skeleton UI window seems to be XUL being loaded. Accordingly, placing
// this call here covers the most ground (as we will call this after
// prefetching and loading all of the dlls in dependentlibs.list, which
// includes xul.dll.)
PollPreXULSkeletonUIEvents();
# endif
}
#endif
return Ok();
}
#if defined(MOZ_WIDGET_GTK) && \
(defined(MOZ_MEMORY) || defined(__FreeBSD__) || defined(__NetBSD__))
# define MOZ_GSLICE_INIT
#endif
#ifdef MOZ_GSLICE_INIT
# include <glib.h>
class GSliceInit {
public:
GSliceInit() {
mHadGSlice = bool(getenv("G_SLICE"));
if (!mHadGSlice) {
// Disable the slice allocator, since jemalloc already uses similar layout
// algorithms, and using a sub-allocator tends to increase fragmentation.
// This must be done before g_thread_init() is called.
// glib >= 2.36 initializes g_slice as a side effect of its various static
// initializers, so this needs to happen before glib is loaded, which is
// this is hooked in XPCOMGlueStartup before libxul is loaded. This
// relies on the main executable not depending on glib.
setenv("G_SLICE", "always-malloc", 1);
}
}
~GSliceInit() {
if (!mHadGSlice) {
unsetenv("G_SLICE");
}
}
private:
bool mHadGSlice;
};
#endif
namespace mozilla {
BootstrapResult GetBootstrap(const char* aXPCOMFile,
LibLoadingStrategy aLibLoadingStrategy) {
#ifdef MOZ_GSLICE_INIT
GSliceInit gSliceInit;
#endif
if (!aXPCOMFile) {
return Err(AsVariant(NS_ERROR_INVALID_ARG));
}
char* lastSlash =
strrchr(const_cast<char*>(aXPCOMFile), XPCOM_FILE_PATH_SEPARATOR[0]);
if (!lastSlash) {
return Err(AsVariant(NS_ERROR_FILE_INVALID_PATH));
}
size_t base_len = size_t(lastSlash - aXPCOMFile) + 1;
UniqueFreePtr<char> file(
reinterpret_cast<char*>(malloc(base_len + sizeof(XPCOM_DLL))));
memcpy(file.get(), aXPCOMFile, base_len);
memcpy(file.get() + base_len, XPCOM_DLL, sizeof(XPCOM_DLL));
MOZ_TRY(XPCOMGlueLoad(file.get(), aLibLoadingStrategy));
if (!sTop) {
return Err(AsVariant(NS_ERROR_NOT_AVAILABLE));
}
#if defined(XP_WIN) && defined(_M_X64) && defined(MOZ_DIAGNOSTIC_ASSERT_ENABLED)
auto check = reinterpret_cast<decltype(&XRE_CheckBlockScopeStaticVarInit)>(
GetSymbol(sTop->libHandle, "XRE_CheckBlockScopeStaticVarInit"));
uint32_t xulTlsIndex = 0;
// HACK: if `check` is nullptr, xul.dll doesn't have the above export. Skip
if (check && !check(&xulTlsIndex)) {
// Unload xul, then load it again while recording single-step data.
XPCOMGlueUnload();
static constexpr int kMaxStepsNtdll = 0xc000;
static constexpr int kMaxErrorStatesNtdll = 0x200;
using NtdllSingleStepData =
ModuleSingleStepData<kMaxStepsNtdll, kMaxErrorStatesNtdll>;
XPCOMGlueLoadResult result = Err(AsVariant(NS_ERROR_FAILURE));
WindowsDiagnosticsError rv = CollectModuleSingleStepData<
kMaxStepsNtdll, kMaxErrorStatesNtdll>(
L"ntdll.dll",
[&result, &file, aLibLoadingStrategy]() {
result = XPCOMGlueLoad(file.get(), aLibLoadingStrategy);
},
[&result, xulTlsIndex](const NtdllSingleStepData& aData) {
bool didReload = false;
bool isStillBroken = false;
uint32_t newXulTlsIndex = 0;
if (result.isOk() && sTop) {
auto check =
reinterpret_cast<decltype(&XRE_CheckBlockScopeStaticVarInit)>(
GetSymbol(sTop->libHandle,
"XRE_CheckBlockScopeStaticVarInit"));
if (check) {
didReload = true;
isStillBroken = !check(&newXulTlsIndex);
}
}
// Crashing here gives access to the single-step data on stack.
MOZ_CRASH_UNSAFE_PRINTF(
"Detected lack of initialization of block-scope static variables "
"in xul, got single-step data (didReload=%d, isStillBroken=%d, "
"xulTlsIndex=%u, newXulTlsIndex=%u)",
didReload, isStillBroken, xulTlsIndex, newXulTlsIndex);
},
InstructionFilter::CallRet);
MOZ_CRASH_UNSAFE_PRINTF(
"Detected lack of initialization of block-scope static variables in "
"xul, failed to collect single-step data (rv=%d)",
static_cast<int>(rv));
}
#endif // XP_WIN && _M_X64 && MOZ_DIAGNOSTIC_ASSERT_ENABLED
GetBootstrapType func =
(GetBootstrapType)GetSymbol(sTop->libHandle, "XRE_GetBootstrap");
if (!func) {
return Err(AsVariant(NS_ERROR_NOT_AVAILABLE));
}
Bootstrap::UniquePtr b;
(*func)(b);
return b;
}
} // namespace mozilla