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-rw-r--r--tools/profiler/lul/AutoObjectMapper.cpp207
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diff --git a/tools/profiler/lul/AutoObjectMapper.cpp b/tools/profiler/lul/AutoObjectMapper.cpp
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+++ b/tools/profiler/lul/AutoObjectMapper.cpp
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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
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include <sys/mman.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+
+#include "mozilla/Assertions.h"
+#include "mozilla/Sprintf.h"
+
+#include "PlatformMacros.h"
+#include "AutoObjectMapper.h"
+
+#if defined(SPS_OS_android) && !defined(MOZ_WIDGET_GONK)
+# include <dlfcn.h>
+# include "mozilla/Types.h"
+ // FIXME move these out of mozglue/linker/ElfLoader.h into their
+ // own header, so as to avoid conflicts arising from two definitions
+ // of Array
+ extern "C" {
+ MFBT_API size_t
+ __dl_get_mappable_length(void *handle);
+ MFBT_API void *
+ __dl_mmap(void *handle, void *addr, size_t length, off_t offset);
+ MFBT_API void
+ __dl_munmap(void *handle, void *addr, size_t length);
+ }
+ // The following are for get_installation_lib_dir()
+# include "nsString.h"
+# include "nsDirectoryServiceUtils.h"
+# include "nsDirectoryServiceDefs.h"
+#endif
+
+
+// A helper function for creating failure error messages in
+// AutoObjectMapper*::Map.
+static void
+failedToMessage(void(*aLog)(const char*),
+ const char* aHowFailed, std::string aFileName)
+{
+ char buf[300];
+ SprintfLiteral(buf, "AutoObjectMapper::Map: Failed to %s \'%s\'",
+ aHowFailed, aFileName.c_str());
+ buf[sizeof(buf)-1] = 0;
+ aLog(buf);
+}
+
+
+AutoObjectMapperPOSIX::AutoObjectMapperPOSIX(void(*aLog)(const char*))
+ : mImage(nullptr)
+ , mSize(0)
+ , mLog(aLog)
+ , mIsMapped(false)
+{}
+
+AutoObjectMapperPOSIX::~AutoObjectMapperPOSIX() {
+ if (!mIsMapped) {
+ // There's nothing to do.
+ MOZ_ASSERT(!mImage);
+ MOZ_ASSERT(mSize == 0);
+ return;
+ }
+ MOZ_ASSERT(mSize > 0);
+ // The following assertion doesn't necessarily have to be true,
+ // but we assume (reasonably enough) that no mmap facility would
+ // be crazy enough to map anything at page zero.
+ MOZ_ASSERT(mImage);
+ munmap(mImage, mSize);
+}
+
+bool AutoObjectMapperPOSIX::Map(/*OUT*/void** start, /*OUT*/size_t* length,
+ std::string fileName)
+{
+ MOZ_ASSERT(!mIsMapped);
+
+ int fd = open(fileName.c_str(), O_RDONLY);
+ if (fd == -1) {
+ failedToMessage(mLog, "open", fileName);
+ return false;
+ }
+
+ struct stat st;
+ int err = fstat(fd, &st);
+ size_t sz = (err == 0) ? st.st_size : 0;
+ if (err != 0 || sz == 0) {
+ failedToMessage(mLog, "fstat", fileName);
+ close(fd);
+ return false;
+ }
+
+ void* image = mmap(nullptr, sz, PROT_READ, MAP_SHARED, fd, 0);
+ if (image == MAP_FAILED) {
+ failedToMessage(mLog, "mmap", fileName);
+ close(fd);
+ return false;
+ }
+
+ close(fd);
+ mIsMapped = true;
+ mImage = *start = image;
+ mSize = *length = sz;
+ return true;
+}
+
+
+#if defined(SPS_OS_android) && !defined(MOZ_WIDGET_GONK)
+// A helper function for AutoObjectMapperFaultyLib::Map. Finds out
+// where the installation's lib directory is, since we'll have to look
+// in there to get hold of libmozglue.so. Returned C string is heap
+// allocated and the caller must deallocate it.
+static char*
+get_installation_lib_dir()
+{
+ nsCOMPtr<nsIProperties>
+ directoryService(do_GetService(NS_DIRECTORY_SERVICE_CONTRACTID));
+ if (!directoryService) {
+ return nullptr;
+ }
+ nsCOMPtr<nsIFile> greDir;
+ nsresult rv = directoryService->Get(NS_GRE_DIR, NS_GET_IID(nsIFile),
+ getter_AddRefs(greDir));
+ if (NS_FAILED(rv)) return nullptr;
+ nsCString path;
+ rv = greDir->GetNativePath(path);
+ if (NS_FAILED(rv)) {
+ return nullptr;
+ }
+ return strdup(path.get());
+}
+
+AutoObjectMapperFaultyLib::AutoObjectMapperFaultyLib(void(*aLog)(const char*))
+ : AutoObjectMapperPOSIX(aLog)
+ , mHdl(nullptr)
+{}
+
+AutoObjectMapperFaultyLib::~AutoObjectMapperFaultyLib() {
+ if (mHdl) {
+ // We've got an object mapped by faulty.lib. Unmap it via faulty.lib.
+ MOZ_ASSERT(mSize > 0);
+ // Assert on the basis that no valid mapping would start at page zero.
+ MOZ_ASSERT(mImage);
+ __dl_munmap(mHdl, mImage, mSize);
+ dlclose(mHdl);
+ // Stop assertions in ~AutoObjectMapperPOSIX from failing.
+ mImage = nullptr;
+ mSize = 0;
+ }
+ // At this point the parent class destructor, ~AutoObjectMapperPOSIX,
+ // gets called. If that has something mapped in the normal way, it
+ // will unmap it in the normal way. Unfortunately there's no
+ // obvious way to enforce the requirement that the object is mapped
+ // either by faulty.lib or by the parent class, but not by both.
+}
+
+bool AutoObjectMapperFaultyLib::Map(/*OUT*/void** start, /*OUT*/size_t* length,
+ std::string fileName)
+{
+ MOZ_ASSERT(!mHdl);
+
+ if (fileName == "libmozglue.so") {
+
+ // Do (2) in the comment above.
+ char* libdir = get_installation_lib_dir();
+ if (libdir) {
+ fileName = std::string(libdir) + "/lib/" + fileName;
+ free(libdir);
+ }
+ // Hand the problem off to the standard mapper.
+ return AutoObjectMapperPOSIX::Map(start, length, fileName);
+
+ } else {
+
+ // Do cases (1) and (3) in the comment above. We have to
+ // grapple with faulty.lib directly.
+ void* hdl = dlopen(fileName.c_str(), RTLD_GLOBAL | RTLD_LAZY);
+ if (!hdl) {
+ failedToMessage(mLog, "get handle for ELF file", fileName);
+ return false;
+ }
+
+ size_t sz = __dl_get_mappable_length(hdl);
+ if (sz == 0) {
+ dlclose(hdl);
+ failedToMessage(mLog, "get size for ELF file", fileName);
+ return false;
+ }
+
+ void* image = __dl_mmap(hdl, nullptr, sz, 0);
+ if (image == MAP_FAILED) {
+ dlclose(hdl);
+ failedToMessage(mLog, "mmap ELF file", fileName);
+ return false;
+ }
+
+ mHdl = hdl;
+ mImage = *start = image;
+ mSize = *length = sz;
+ return true;
+ }
+}
+
+#endif // defined(SPS_OS_android) && !defined(MOZ_WIDGET_GONK)