1 /*
2  * Copyright (C) 2015 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #include "io/ZipArchive.h"
18 
19 #include "androidfw/Source.h"
20 #include "trace/TraceBuffer.h"
21 #include "util/Files.h"
22 #include "util/Util.h"
23 #include "utils/FileMap.h"
24 #include "ziparchive/zip_archive.h"
25 
26 using ::android::StringPiece;
27 
28 namespace aapt {
29 namespace io {
30 
ZipFile(ZipArchiveHandle handle,const ZipEntry & entry,const android::Source & source)31 ZipFile::ZipFile(ZipArchiveHandle handle, const ZipEntry& entry, const android::Source& source)
32     : zip_handle_(handle), zip_entry_(entry), source_(source) {
33 }
34 
OpenAsData()35 std::unique_ptr<IData> ZipFile::OpenAsData() {
36   // The file will fail to be mmaped if it is empty
37   if (zip_entry_.uncompressed_length == 0) {
38     return util::make_unique<EmptyData>();
39   }
40 
41   if (zip_entry_.method == kCompressStored) {
42     int fd = GetFileDescriptor(zip_handle_);
43 
44     android::FileMap file_map;
45     bool result = file_map.create(nullptr, fd, zip_entry_.offset,
46                                   zip_entry_.uncompressed_length, true);
47     if (!result) {
48       return {};
49     }
50     return util::make_unique<MmappedData>(std::move(file_map));
51 
52   } else {
53     std::unique_ptr<uint8_t[]> data =
54         std::unique_ptr<uint8_t[]>(new uint8_t[zip_entry_.uncompressed_length]);
55     int32_t result =
56         ExtractToMemory(zip_handle_, &zip_entry_, data.get(),
57                         static_cast<uint32_t>(zip_entry_.uncompressed_length));
58     if (result != 0) {
59       return {};
60     }
61     return util::make_unique<MallocData>(std::move(data),
62                                          zip_entry_.uncompressed_length);
63   }
64 }
65 
OpenInputStream()66 std::unique_ptr<io::InputStream> ZipFile::OpenInputStream() {
67   return OpenAsData();
68 }
69 
GetSource() const70 const android::Source& ZipFile::GetSource() const {
71   return source_;
72 }
73 
WasCompressed()74 bool ZipFile::WasCompressed() {
75   return zip_entry_.method != kCompressStored;
76 }
77 
ZipFileCollectionIterator(ZipFileCollection * collection)78 ZipFileCollectionIterator::ZipFileCollectionIterator(
79     ZipFileCollection* collection)
80     : current_(collection->files_.begin()), end_(collection->files_.end()) {}
81 
HasNext()82 bool ZipFileCollectionIterator::HasNext() {
83   return current_ != end_;
84 }
85 
Next()86 IFile* ZipFileCollectionIterator::Next() {
87   IFile* result = current_->get();
88   ++current_;
89   return result;
90 }
91 
ZipFileCollection()92 ZipFileCollection::ZipFileCollection() : handle_(nullptr) {}
93 
Create(StringPiece path,std::string * out_error)94 std::unique_ptr<ZipFileCollection> ZipFileCollection::Create(StringPiece path,
95                                                              std::string* out_error) {
96   TRACE_CALL();
97   constexpr static const int32_t kEmptyArchive = -6;
98 
99   std::unique_ptr<ZipFileCollection> collection =
100       std::unique_ptr<ZipFileCollection>(new ZipFileCollection());
101 
102   int32_t result = OpenArchive(path.data(), &collection->handle_);
103   if (result != 0) {
104     // If a zip is empty, result will be an error code. This is fine and we
105     // should
106     // return an empty ZipFileCollection.
107     if (result == kEmptyArchive) {
108       return collection;
109     }
110 
111     if (out_error) *out_error = ErrorCodeString(result);
112     return {};
113   }
114 
115   void* cookie = nullptr;
116   result = StartIteration(collection->handle_, &cookie);
117   if (result != 0) {
118     if (out_error) *out_error = ErrorCodeString(result);
119     return {};
120   }
121 
122   using IterationEnder = std::unique_ptr<void, decltype(EndIteration)*>;
123   IterationEnder iteration_ender(cookie, EndIteration);
124 
125   std::string zip_entry_path;
126   ZipEntry zip_data;
127   while ((result = Next(cookie, &zip_data, &zip_entry_path)) == 0) {
128     // Do not add folders to the file collection
129     if (util::EndsWith(zip_entry_path, "/")) {
130       continue;
131     }
132 
133     std::unique_ptr<IFile> file = util::make_unique<ZipFile>(collection->handle_, zip_data,
134                                                              android::Source(zip_entry_path, path));
135     collection->files_by_name_[zip_entry_path] = file.get();
136     collection->files_.push_back(std::move(file));
137   }
138 
139   if (result != -1) {
140     if (out_error) *out_error = ErrorCodeString(result);
141     return {};
142   }
143 
144   return collection;
145 }
146 
FindFile(StringPiece path)147 IFile* ZipFileCollection::FindFile(StringPiece path) {
148   auto iter = files_by_name_.find(path);
149   if (iter != files_by_name_.end()) {
150     return iter->second;
151   }
152   return nullptr;
153 }
154 
Iterator()155 std::unique_ptr<IFileCollectionIterator> ZipFileCollection::Iterator() {
156   return util::make_unique<ZipFileCollectionIterator>(this);
157 }
158 
GetDirSeparator()159 char ZipFileCollection::GetDirSeparator() {
160   // According to the zip file specification, section  4.4.17.1:
161   // "All slashes MUST be forward slashes '/' as opposed to backwards slashes '\' for compatibility
162   // with Amiga and UNIX file systems etc."
163   return '/';
164 }
165 
~ZipFileCollection()166 ZipFileCollection::~ZipFileCollection() {
167   if (handle_) {
168     CloseArchive(handle_);
169   }
170 }
171 
172 }  // namespace io
173 }  // namespace aapt
174