1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/tools/profiler/AutoObjectMapper.cpp Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,207 @@
1.4 +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
1.5 +/* vim: set ts=8 sts=2 et sw=2 tw=80: */
1.6 +/* This Source Code Form is subject to the terms of the Mozilla Public
1.7 + * License, v. 2.0. If a copy of the MPL was not distributed with this
1.8 + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
1.9 +
1.10 +#include <sys/mman.h>
1.11 +#include <unistd.h>
1.12 +#include <sys/types.h>
1.13 +#include <sys/stat.h>
1.14 +#include <fcntl.h>
1.15 +
1.16 +#include "mozilla/Assertions.h"
1.17 +#include "mozilla/NullPtr.h"
1.18 +
1.19 +#include "PlatformMacros.h"
1.20 +#include "AutoObjectMapper.h"
1.21 +
1.22 +#if defined(SPS_OS_android) && !defined(MOZ_WIDGET_GONK)
1.23 +# include <dlfcn.h>
1.24 +# include "mozilla/Types.h"
1.25 + // FIXME move these out of mozglue/linker/ElfLoader.h into their
1.26 + // own header, so as to avoid conflicts arising from two definitions
1.27 + // of Array
1.28 + extern "C" {
1.29 + MFBT_API size_t
1.30 + __dl_get_mappable_length(void *handle);
1.31 + MFBT_API void *
1.32 + __dl_mmap(void *handle, void *addr, size_t length, off_t offset);
1.33 + MFBT_API void
1.34 + __dl_munmap(void *handle, void *addr, size_t length);
1.35 + }
1.36 + // The following are for get_installation_lib_dir()
1.37 +# include "nsString.h"
1.38 +# include "nsDirectoryServiceUtils.h"
1.39 +# include "nsDirectoryServiceDefs.h"
1.40 +#endif
1.41 +
1.42 +
1.43 +// A helper function for creating failure error messages in
1.44 +// AutoObjectMapper*::Map.
1.45 +static void
1.46 +failedToMessage(void(*aLog)(const char*),
1.47 + const char* aHowFailed, std::string aFileName)
1.48 +{
1.49 + char buf[300];
1.50 + snprintf(buf, sizeof(buf), "AutoObjectMapper::Map: Failed to %s \'%s\'",
1.51 + aHowFailed, aFileName.c_str());
1.52 + buf[sizeof(buf)-1] = 0;
1.53 + aLog(buf);
1.54 +}
1.55 +
1.56 +
1.57 +AutoObjectMapperPOSIX::AutoObjectMapperPOSIX(void(*aLog)(const char*))
1.58 + : mImage(nullptr)
1.59 + , mSize(0)
1.60 + , mLog(aLog)
1.61 + , mIsMapped(false)
1.62 +{}
1.63 +
1.64 +AutoObjectMapperPOSIX::~AutoObjectMapperPOSIX() {
1.65 + if (!mIsMapped) {
1.66 + // There's nothing to do.
1.67 + MOZ_ASSERT(!mImage);
1.68 + MOZ_ASSERT(mSize == 0);
1.69 + return;
1.70 + }
1.71 + MOZ_ASSERT(mSize > 0);
1.72 + // The following assertion doesn't necessarily have to be true,
1.73 + // but we assume (reasonably enough) that no mmap facility would
1.74 + // be crazy enough to map anything at page zero.
1.75 + MOZ_ASSERT(mImage);
1.76 + munmap(mImage, mSize);
1.77 +}
1.78 +
1.79 +bool AutoObjectMapperPOSIX::Map(/*OUT*/void** start, /*OUT*/size_t* length,
1.80 + std::string fileName)
1.81 +{
1.82 + MOZ_ASSERT(!mIsMapped);
1.83 +
1.84 + int fd = open(fileName.c_str(), O_RDONLY);
1.85 + if (fd == -1) {
1.86 + failedToMessage(mLog, "open", fileName);
1.87 + return false;
1.88 + }
1.89 +
1.90 + struct stat st;
1.91 + int err = fstat(fd, &st);
1.92 + size_t sz = (err == 0) ? st.st_size : 0;
1.93 + if (err != 0 || sz == 0) {
1.94 + failedToMessage(mLog, "fstat", fileName);
1.95 + close(fd);
1.96 + return false;
1.97 + }
1.98 +
1.99 + void* image = mmap(nullptr, sz, PROT_READ, MAP_SHARED, fd, 0);
1.100 + if (image == MAP_FAILED) {
1.101 + failedToMessage(mLog, "mmap", fileName);
1.102 + close(fd);
1.103 + return false;
1.104 + }
1.105 +
1.106 + close(fd);
1.107 + mIsMapped = true;
1.108 + mImage = *start = image;
1.109 + mSize = *length = sz;
1.110 + return true;
1.111 +}
1.112 +
1.113 +
1.114 +#if defined(SPS_OS_android) && !defined(MOZ_WIDGET_GONK)
1.115 +// A helper function for AutoObjectMapperFaultyLib::Map. Finds out
1.116 +// where the installation's lib directory is, since we'll have to look
1.117 +// in there to get hold of libmozglue.so. Returned C string is heap
1.118 +// allocated and the caller must deallocate it.
1.119 +static char*
1.120 +get_installation_lib_dir()
1.121 +{
1.122 + nsCOMPtr<nsIProperties>
1.123 + directoryService(do_GetService(NS_DIRECTORY_SERVICE_CONTRACTID));
1.124 + if (!directoryService) {
1.125 + return nullptr;
1.126 + }
1.127 + nsCOMPtr<nsIFile> greDir;
1.128 + nsresult rv = directoryService->Get(NS_GRE_DIR, NS_GET_IID(nsIFile),
1.129 + getter_AddRefs(greDir));
1.130 + if (NS_FAILED(rv)) return nullptr;
1.131 + nsCString path;
1.132 + rv = greDir->GetNativePath(path);
1.133 + if (NS_FAILED(rv)) {
1.134 + return nullptr;
1.135 + }
1.136 + return strdup(path.get());
1.137 +}
1.138 +
1.139 +AutoObjectMapperFaultyLib::AutoObjectMapperFaultyLib(void(*aLog)(const char*))
1.140 + : AutoObjectMapperPOSIX(aLog)
1.141 + , mHdl(nullptr)
1.142 +{}
1.143 +
1.144 +AutoObjectMapperFaultyLib::~AutoObjectMapperFaultyLib() {
1.145 + if (mHdl) {
1.146 + // We've got an object mapped by faulty.lib. Unmap it via faulty.lib.
1.147 + MOZ_ASSERT(mSize > 0);
1.148 + // Assert on the basis that no valid mapping would start at page zero.
1.149 + MOZ_ASSERT(mImage);
1.150 + __dl_munmap(mHdl, mImage, mSize);
1.151 + dlclose(mHdl);
1.152 + // Stop assertions in ~AutoObjectMapperPOSIX from failing.
1.153 + mImage = nullptr;
1.154 + mSize = 0;
1.155 + }
1.156 + // At this point the parent class destructor, ~AutoObjectMapperPOSIX,
1.157 + // gets called. If that has something mapped in the normal way, it
1.158 + // will unmap it in the normal way. Unfortunately there's no
1.159 + // obvious way to enforce the requirement that the object is mapped
1.160 + // either by faulty.lib or by the parent class, but not by both.
1.161 +}
1.162 +
1.163 +bool AutoObjectMapperFaultyLib::Map(/*OUT*/void** start, /*OUT*/size_t* length,
1.164 + std::string fileName)
1.165 +{
1.166 + MOZ_ASSERT(!mHdl);
1.167 +
1.168 + if (fileName == "libmozglue.so") {
1.169 +
1.170 + // Do (2) in the comment above.
1.171 + char* libdir = get_installation_lib_dir();
1.172 + if (libdir) {
1.173 + fileName = std::string(libdir) + "/lib/" + fileName;
1.174 + free(libdir);
1.175 + }
1.176 + // Hand the problem off to the standard mapper.
1.177 + return AutoObjectMapperPOSIX::Map(start, length, fileName);
1.178 +
1.179 + } else {
1.180 +
1.181 + // Do cases (1) and (3) in the comment above. We have to
1.182 + // grapple with faulty.lib directly.
1.183 + void* hdl = dlopen(fileName.c_str(), RTLD_GLOBAL | RTLD_LAZY);
1.184 + if (!hdl) {
1.185 + failedToMessage(mLog, "get handle for ELF file", fileName);
1.186 + return false;
1.187 + }
1.188 +
1.189 + size_t sz = __dl_get_mappable_length(hdl);
1.190 + if (sz == 0) {
1.191 + dlclose(hdl);
1.192 + failedToMessage(mLog, "get size for ELF file", fileName);
1.193 + return false;
1.194 + }
1.195 +
1.196 + void* image = __dl_mmap(hdl, nullptr, sz, 0);
1.197 + if (image == MAP_FAILED) {
1.198 + dlclose(hdl);
1.199 + failedToMessage(mLog, "mmap ELF file", fileName);
1.200 + return false;
1.201 + }
1.202 +
1.203 + mHdl = hdl;
1.204 + mImage = *start = image;
1.205 + mSize = *length = sz;
1.206 + return true;
1.207 + }
1.208 +}
1.209 +
1.210 +#endif // defined(SPS_OS_android) && !defined(MOZ_WIDGET_GONK)
