From 5f8de423f190bbb79a62f804151bc24824fa32d8 Mon Sep 17 00:00:00 2001 From: "Matt A. Tobin" Date: Fri, 2 Feb 2018 04:16:08 -0500 Subject: Add m-esr52 at 52.6.0 --- mozglue/linker/Zip.cpp | 229 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 229 insertions(+) create mode 100644 mozglue/linker/Zip.cpp (limited to 'mozglue/linker/Zip.cpp') diff --git a/mozglue/linker/Zip.cpp b/mozglue/linker/Zip.cpp new file mode 100644 index 000000000..d141eaa45 --- /dev/null +++ b/mozglue/linker/Zip.cpp @@ -0,0 +1,229 @@ +/* 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 +#include +#include +#include +#include +#include +#include +#include "Logging.h" +#include "Zip.h" + +already_AddRefed +Zip::Create(const char *filename) +{ + /* Open and map the file in memory */ + AutoCloseFD fd(open(filename, O_RDONLY)); + if (fd == -1) { + ERROR("Error opening %s: %s", filename, strerror(errno)); + return nullptr; + } + struct stat st; + if (fstat(fd, &st) == -1) { + ERROR("Error stating %s: %s", filename, strerror(errno)); + return nullptr; + } + size_t size = st.st_size; + if (size <= sizeof(CentralDirectoryEnd)) { + ERROR("Error reading %s: too short", filename); + return nullptr; + } + void *mapped = mmap(nullptr, size, PROT_READ, MAP_SHARED, fd, 0); + if (mapped == MAP_FAILED) { + ERROR("Error mmapping %s: %s", filename, strerror(errno)); + return nullptr; + } + DEBUG_LOG("Mapped %s @%p", filename, mapped); + + return Create(filename, mapped, size); +} + +already_AddRefed +Zip::Create(const char *filename, void *mapped, size_t size) +{ + RefPtr zip = new Zip(filename, mapped, size); + + // If neither the first Local File entry nor central directory entries + // have been found, the zip was invalid. + if (!zip->nextFile && !zip->entries) { + ERROR("%s - Invalid zip", filename); + return nullptr; + } + + ZipCollection::Singleton.Register(zip); + return zip.forget(); +} + +Zip::Zip(const char *filename, void *mapped, size_t size) +: name(filename ? strdup(filename) : nullptr) +, mapped(mapped) +, size(size) +, nextFile(LocalFile::validate(mapped)) // first Local File entry +, nextDir(nullptr) +, entries(nullptr) +{ + pthread_mutex_init(&mutex, nullptr); + // If the first local file entry couldn't be found (which can happen + // with optimized jars), check the first central directory entry. + if (!nextFile) + GetFirstEntry(); +} + +Zip::~Zip() +{ + ZipCollection::Forget(this); + if (name) { + munmap(mapped, size); + DEBUG_LOG("Unmapped %s @%p", name, mapped); + free(name); + } + pthread_mutex_destroy(&mutex); +} + +bool +Zip::GetStream(const char *path, Zip::Stream *out) const +{ + AutoLock lock(&mutex); + + DEBUG_LOG("%s - GetFile %s", name, path); + /* Fast path: if the Local File header on store matches, we can return the + * corresponding stream right away. + * However, the Local File header may not contain enough information, in + * which case the 3rd bit on the generalFlag is set. Unfortunately, this + * bit is also set in some archives even when we do have the data (most + * notably the android packages as built by the Mozilla build system). + * So instead of testing the generalFlag bit, only use the fast path when + * we haven't read the central directory entries yet, and when the + * compressed size as defined in the header is not filled (which is a + * normal condition for the bit to be set). */ + if (nextFile && nextFile->GetName().Equals(path) && + !entries && (nextFile->compressedSize != 0)) { + DEBUG_LOG("%s - %s was next file: fast path", name, path); + /* Fill Stream info from Local File header content */ + const char *data = reinterpret_cast(nextFile->GetData()); + out->compressedBuf = data; + out->compressedSize = nextFile->compressedSize; + out->uncompressedSize = nextFile->uncompressedSize; + out->CRC32 = nextFile->CRC32; + out->type = static_cast(uint16_t(nextFile->compression)); + + /* Find the next Local File header. It is usually simply following the + * compressed stream, but in cases where the 3rd bit of the generalFlag + * is set, there is a Data Descriptor header before. */ + data += nextFile->compressedSize; + if ((nextFile->generalFlag & 0x8) && DataDescriptor::validate(data)) { + data += sizeof(DataDescriptor); + } + nextFile = LocalFile::validate(data); + return true; + } + + /* If the directory entry we have in store doesn't match, scan the Central + * Directory for the entry corresponding to the given path */ + if (!nextDir || !nextDir->GetName().Equals(path)) { + const DirectoryEntry *entry = GetFirstEntry(); + DEBUG_LOG("%s - Scan directory entries in search for %s", name, path); + while (entry && !entry->GetName().Equals(path)) { + entry = entry->GetNext(); + } + nextDir = entry; + } + if (!nextDir) { + DEBUG_LOG("%s - Couldn't find %s", name, path); + return false; + } + + /* Find the Local File header corresponding to the Directory entry that + * was found. */ + nextFile = LocalFile::validate(static_cast(mapped) + + nextDir->offset); + if (!nextFile) { + ERROR("%s - Couldn't find the Local File header for %s", name, path); + return false; + } + + /* Fill Stream info from Directory entry content */ + const char *data = reinterpret_cast(nextFile->GetData()); + out->compressedBuf = data; + out->compressedSize = nextDir->compressedSize; + out->uncompressedSize = nextDir->uncompressedSize; + out->CRC32 = nextDir->CRC32; + out->type = static_cast(uint16_t(nextDir->compression)); + + /* Store the next directory entry */ + nextDir = nextDir->GetNext(); + nextFile = nullptr; + return true; +} + +const Zip::DirectoryEntry * +Zip::GetFirstEntry() const +{ + if (entries) + return entries; + + const CentralDirectoryEnd *end = nullptr; + const char *_end = static_cast(mapped) + size + - sizeof(CentralDirectoryEnd); + + /* Scan for the Central Directory End */ + for (; _end > mapped && !end; _end--) + end = CentralDirectoryEnd::validate(_end); + if (!end) { + ERROR("%s - Couldn't find end of central directory record", name); + return nullptr; + } + + entries = DirectoryEntry::validate(static_cast(mapped) + + end->offset); + if (!entries) { + ERROR("%s - Couldn't find central directory record", name); + } + return entries; +} + +ZipCollection ZipCollection::Singleton; + +static pthread_mutex_t sZipCollectionMutex = PTHREAD_MUTEX_INITIALIZER; + +already_AddRefed +ZipCollection::GetZip(const char *path) +{ + { + AutoLock lock(&sZipCollectionMutex); + /* Search the list of Zips we already have for a match */ + for (std::vector::iterator it = Singleton.zips.begin(); + it < Singleton.zips.end(); ++it) { + if ((*it)->GetName() && (strcmp((*it)->GetName(), path) == 0)) { + RefPtr zip = *it; + return zip.forget(); + } + } + } + return Zip::Create(path); +} + +void +ZipCollection::Register(Zip *zip) +{ + AutoLock lock(&sZipCollectionMutex); + DEBUG_LOG("ZipCollection::Register(\"%s\")", zip->GetName()); + Singleton.zips.push_back(zip); +} + +void +ZipCollection::Forget(Zip *zip) +{ + AutoLock lock(&sZipCollectionMutex); + DEBUG_LOG("ZipCollection::Forget(\"%s\")", zip->GetName()); + std::vector::iterator it = std::find(Singleton.zips.begin(), + Singleton.zips.end(), zip); + if (*it == zip) { + Singleton.zips.erase(it); + } else { + DEBUG_LOG("ZipCollection::Forget: didn't find \"%s\" in bookkeeping", zip->GetName()); + } +} -- cgit v1.2.3