• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
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 "format/binary/TableFlattener.h"
18 
19 #include <algorithm>
20 #include <numeric>
21 #include <sstream>
22 #include <type_traits>
23 
24 #include "android-base/logging.h"
25 #include "android-base/macros.h"
26 #include "android-base/stringprintf.h"
27 #include "androidfw/ResourceUtils.h"
28 
29 #include "ResourceTable.h"
30 #include "ResourceValues.h"
31 #include "SdkConstants.h"
32 #include "ValueVisitor.h"
33 #include "format/binary/ChunkWriter.h"
34 #include "format/binary/ResourceTypeExtensions.h"
35 #include "trace/TraceBuffer.h"
36 #include "util/BigBuffer.h"
37 
38 using namespace android;
39 
40 namespace aapt {
41 
42 namespace {
43 
44 template <typename T>
cmp_ids(const T * a,const T * b)45 static bool cmp_ids(const T* a, const T* b) {
46   return a->id.value() < b->id.value();
47 }
48 
strcpy16_htod(uint16_t * dst,size_t len,const StringPiece16 & src)49 static void strcpy16_htod(uint16_t* dst, size_t len, const StringPiece16& src) {
50   if (len == 0) {
51     return;
52   }
53 
54   size_t i;
55   const char16_t* src_data = src.data();
56   for (i = 0; i < len - 1 && i < src.size(); i++) {
57     dst[i] = util::HostToDevice16((uint16_t)src_data[i]);
58   }
59   dst[i] = 0;
60 }
61 
cmp_style_entries(const Style::Entry * a,const Style::Entry * b)62 static bool cmp_style_entries(const Style::Entry* a, const Style::Entry* b) {
63   if (a->key.id) {
64     if (b->key.id) {
65       return cmp_ids_dynamic_after_framework(a->key.id.value(), b->key.id.value());
66     }
67     return true;
68   } else if (!b->key.id) {
69     return a->key.name.value() < b->key.name.value();
70   }
71   return false;
72 }
73 
74 struct FlatEntry {
75   const ResourceTableEntryView* entry;
76   const Value* value;
77 
78   // The entry string pool index to the entry's name.
79   uint32_t entry_key;
80 };
81 
82 class MapFlattenVisitor : public ConstValueVisitor {
83  public:
84   using ConstValueVisitor::Visit;
85 
MapFlattenVisitor(ResTable_entry_ext * out_entry,BigBuffer * buffer)86   MapFlattenVisitor(ResTable_entry_ext* out_entry, BigBuffer* buffer)
87       : out_entry_(out_entry), buffer_(buffer) {
88   }
89 
Visit(const Attribute * attr)90   void Visit(const Attribute* attr) override {
91     {
92       Reference key = Reference(ResourceId(ResTable_map::ATTR_TYPE));
93       BinaryPrimitive val(Res_value::TYPE_INT_DEC, attr->type_mask);
94       FlattenEntry(&key, &val);
95     }
96 
97     if (attr->min_int != std::numeric_limits<int32_t>::min()) {
98       Reference key = Reference(ResourceId(ResTable_map::ATTR_MIN));
99       BinaryPrimitive val(Res_value::TYPE_INT_DEC, static_cast<uint32_t>(attr->min_int));
100       FlattenEntry(&key, &val);
101     }
102 
103     if (attr->max_int != std::numeric_limits<int32_t>::max()) {
104       Reference key = Reference(ResourceId(ResTable_map::ATTR_MAX));
105       BinaryPrimitive val(Res_value::TYPE_INT_DEC, static_cast<uint32_t>(attr->max_int));
106       FlattenEntry(&key, &val);
107     }
108 
109     for (const Attribute::Symbol& s : attr->symbols) {
110       BinaryPrimitive val(s.type, s.value);
111       FlattenEntry(&s.symbol, &val);
112     }
113   }
114 
Visit(const Style * style)115   void Visit(const Style* style) override {
116     if (style->parent) {
117       const Reference& parent_ref = style->parent.value();
118       CHECK(bool(parent_ref.id)) << "parent has no ID";
119       out_entry_->parent.ident = util::HostToDevice32(parent_ref.id.value().id);
120     }
121 
122     // Sort the style.
123     std::vector<const Style::Entry*> sorted_entries;
124     for (const auto& entry : style->entries) {
125       sorted_entries.emplace_back(&entry);
126     }
127 
128     std::sort(sorted_entries.begin(), sorted_entries.end(), cmp_style_entries);
129 
130     for (const Style::Entry* entry : sorted_entries) {
131       FlattenEntry(&entry->key, entry->value.get());
132     }
133   }
134 
Visit(const Styleable * styleable)135   void Visit(const Styleable* styleable) override {
136     for (auto& attr_ref : styleable->entries) {
137       BinaryPrimitive val(Res_value{});
138       FlattenEntry(&attr_ref, &val);
139     }
140   }
141 
Visit(const Array * array)142   void Visit(const Array* array) override {
143     const size_t count = array->elements.size();
144     for (size_t i = 0; i < count; i++) {
145       Reference key(android::ResTable_map::ATTR_MIN + i);
146       FlattenEntry(&key, array->elements[i].get());
147     }
148   }
149 
Visit(const Plural * plural)150   void Visit(const Plural* plural) override {
151     const size_t count = plural->values.size();
152     for (size_t i = 0; i < count; i++) {
153       if (!plural->values[i]) {
154         continue;
155       }
156 
157       ResourceId q;
158       switch (i) {
159         case Plural::Zero:
160           q.id = android::ResTable_map::ATTR_ZERO;
161           break;
162 
163         case Plural::One:
164           q.id = android::ResTable_map::ATTR_ONE;
165           break;
166 
167         case Plural::Two:
168           q.id = android::ResTable_map::ATTR_TWO;
169           break;
170 
171         case Plural::Few:
172           q.id = android::ResTable_map::ATTR_FEW;
173           break;
174 
175         case Plural::Many:
176           q.id = android::ResTable_map::ATTR_MANY;
177           break;
178 
179         case Plural::Other:
180           q.id = android::ResTable_map::ATTR_OTHER;
181           break;
182 
183         default:
184           LOG(FATAL) << "unhandled plural type";
185           break;
186       }
187 
188       Reference key(q);
189       FlattenEntry(&key, plural->values[i].get());
190     }
191   }
192 
193   /**
194    * Call this after visiting a Value. This will finish any work that
195    * needs to be done to prepare the entry.
196    */
Finish()197   void Finish() {
198     out_entry_->count = util::HostToDevice32(entry_count_);
199   }
200 
201  private:
202   DISALLOW_COPY_AND_ASSIGN(MapFlattenVisitor);
203 
FlattenKey(const Reference * key,ResTable_map * out_entry)204   void FlattenKey(const Reference* key, ResTable_map* out_entry) {
205     CHECK(bool(key->id)) << "key has no ID";
206     out_entry->name.ident = util::HostToDevice32(key->id.value().id);
207   }
208 
FlattenValue(const Item * value,ResTable_map * out_entry)209   void FlattenValue(const Item* value, ResTable_map* out_entry) {
210     CHECK(value->Flatten(&out_entry->value)) << "flatten failed";
211   }
212 
FlattenEntry(const Reference * key,Item * value)213   void FlattenEntry(const Reference* key, Item* value) {
214     ResTable_map* out_entry = buffer_->NextBlock<ResTable_map>();
215     FlattenKey(key, out_entry);
216     FlattenValue(value, out_entry);
217     out_entry->value.size = util::HostToDevice16(sizeof(out_entry->value));
218     entry_count_++;
219   }
220 
221   ResTable_entry_ext* out_entry_;
222   BigBuffer* buffer_;
223   size_t entry_count_ = 0;
224 };
225 
226 struct OverlayableChunk {
227   std::string actor;
228   Source source;
229   std::map<PolicyFlags, std::set<ResourceId>> policy_ids;
230 };
231 
232 class PackageFlattener {
233  public:
PackageFlattener(IAaptContext * context,const ResourceTablePackageView & package,const std::map<size_t,std::string> * shared_libs,bool use_sparse_entries,bool collapse_key_stringpool,const std::set<ResourceName> & name_collapse_exemptions)234   PackageFlattener(IAaptContext* context, const ResourceTablePackageView& package,
235                    const std::map<size_t, std::string>* shared_libs, bool use_sparse_entries,
236                    bool collapse_key_stringpool,
237                    const std::set<ResourceName>& name_collapse_exemptions)
238       : context_(context),
239         diag_(context->GetDiagnostics()),
240         package_(package),
241         shared_libs_(shared_libs),
242         use_sparse_entries_(use_sparse_entries),
243         collapse_key_stringpool_(collapse_key_stringpool),
244         name_collapse_exemptions_(name_collapse_exemptions) {
245   }
246 
FlattenPackage(BigBuffer * buffer)247   bool FlattenPackage(BigBuffer* buffer) {
248     TRACE_CALL();
249     ChunkWriter pkg_writer(buffer);
250     ResTable_package* pkg_header = pkg_writer.StartChunk<ResTable_package>(RES_TABLE_PACKAGE_TYPE);
251     pkg_header->id = util::HostToDevice32(package_.id.value());
252 
253     // AAPT truncated the package name, so do the same.
254     // Shared libraries require full package names, so don't truncate theirs.
255     if (context_->GetPackageType() != PackageType::kApp &&
256         package_.name.size() >= arraysize(pkg_header->name)) {
257       diag_->Error(DiagMessage() << "package name '" << package_.name
258                                  << "' is too long. "
259                                     "Shared libraries cannot have truncated package names");
260       return false;
261     }
262 
263     // Copy the package name in device endianness.
264     strcpy16_htod(pkg_header->name, arraysize(pkg_header->name), util::Utf8ToUtf16(package_.name));
265 
266     // Serialize the types. We do this now so that our type and key strings
267     // are populated. We write those first.
268     BigBuffer type_buffer(1024);
269     FlattenTypes(&type_buffer);
270 
271     pkg_header->typeStrings = util::HostToDevice32(pkg_writer.size());
272     StringPool::FlattenUtf16(pkg_writer.buffer(), type_pool_, diag_);
273 
274     pkg_header->keyStrings = util::HostToDevice32(pkg_writer.size());
275     StringPool::FlattenUtf8(pkg_writer.buffer(), key_pool_, diag_);
276 
277     // Append the types.
278     buffer->AppendBuffer(std::move(type_buffer));
279 
280     // If there are libraries (or if the package ID is 0x00), encode a library chunk.
281     if (package_.id.value() == 0x00 || !shared_libs_->empty()) {
282       FlattenLibrarySpec(buffer);
283     }
284 
285     if (!FlattenOverlayable(buffer)) {
286       return false;
287     }
288 
289     if (!FlattenAliases(buffer)) {
290       return false;
291     }
292 
293     pkg_writer.Finish();
294     return true;
295   }
296 
297  private:
298   DISALLOW_COPY_AND_ASSIGN(PackageFlattener);
299 
300   template <typename T, bool IsItem>
WriteEntry(FlatEntry * entry,BigBuffer * buffer)301   T* WriteEntry(FlatEntry* entry, BigBuffer* buffer) {
302     static_assert(
303         std::is_same<ResTable_entry, T>::value || std::is_same<ResTable_entry_ext, T>::value,
304         "T must be ResTable_entry or ResTable_entry_ext");
305 
306     T* result = buffer->NextBlock<T>();
307     ResTable_entry* out_entry = (ResTable_entry*)result;
308     if (entry->entry->visibility.level == Visibility::Level::kPublic) {
309       out_entry->flags |= ResTable_entry::FLAG_PUBLIC;
310     }
311 
312     if (entry->value->IsWeak()) {
313       out_entry->flags |= ResTable_entry::FLAG_WEAK;
314     }
315 
316     if (!IsItem) {
317       out_entry->flags |= ResTable_entry::FLAG_COMPLEX;
318     }
319 
320     out_entry->flags = util::HostToDevice16(out_entry->flags);
321     out_entry->key.index = util::HostToDevice32(entry->entry_key);
322     out_entry->size = util::HostToDevice16(sizeof(T));
323     return result;
324   }
325 
FlattenValue(FlatEntry * entry,BigBuffer * buffer)326   bool FlattenValue(FlatEntry* entry, BigBuffer* buffer) {
327     if (const Item* item = ValueCast<Item>(entry->value)) {
328       WriteEntry<ResTable_entry, true>(entry, buffer);
329       Res_value* outValue = buffer->NextBlock<Res_value>();
330       CHECK(item->Flatten(outValue)) << "flatten failed";
331       outValue->size = util::HostToDevice16(sizeof(*outValue));
332     } else {
333       ResTable_entry_ext* out_entry = WriteEntry<ResTable_entry_ext, false>(entry, buffer);
334       MapFlattenVisitor visitor(out_entry, buffer);
335       entry->value->Accept(&visitor);
336       visitor.Finish();
337     }
338     return true;
339   }
340 
FlattenConfig(const ResourceTableTypeView & type,const ConfigDescription & config,const size_t num_total_entries,std::vector<FlatEntry> * entries,BigBuffer * buffer)341   bool FlattenConfig(const ResourceTableTypeView& type, const ConfigDescription& config,
342                      const size_t num_total_entries, std::vector<FlatEntry>* entries,
343                      BigBuffer* buffer) {
344     CHECK(num_total_entries != 0);
345     CHECK(num_total_entries <= std::numeric_limits<uint16_t>::max());
346 
347     ChunkWriter type_writer(buffer);
348     ResTable_type* type_header = type_writer.StartChunk<ResTable_type>(RES_TABLE_TYPE_TYPE);
349     type_header->id = type.id.value();
350     type_header->config = config;
351     type_header->config.swapHtoD();
352 
353     std::vector<uint32_t> offsets;
354     offsets.resize(num_total_entries, 0xffffffffu);
355 
356     BigBuffer values_buffer(512);
357     for (FlatEntry& flat_entry : *entries) {
358       CHECK(static_cast<size_t>(flat_entry.entry->id.value()) < num_total_entries);
359       offsets[flat_entry.entry->id.value()] = values_buffer.size();
360       if (!FlattenValue(&flat_entry, &values_buffer)) {
361         diag_->Error(DiagMessage()
362                      << "failed to flatten resource '"
363                      << ResourceNameRef(package_.name, type.type, flat_entry.entry->name)
364                      << "' for configuration '" << config << "'");
365         return false;
366       }
367     }
368 
369     bool sparse_encode = use_sparse_entries_;
370 
371     // Only sparse encode if the entries will be read on platforms O+.
372     sparse_encode =
373         sparse_encode && (context_->GetMinSdkVersion() >= SDK_O || config.sdkVersion >= SDK_O);
374 
375     // Only sparse encode if the offsets are representable in 2 bytes.
376     sparse_encode =
377         sparse_encode && (values_buffer.size() / 4u) <= std::numeric_limits<uint16_t>::max();
378 
379     // Only sparse encode if the ratio of populated entries to total entries is below some
380     // threshold.
381     sparse_encode =
382         sparse_encode && ((100 * entries->size()) / num_total_entries) < kSparseEncodingThreshold;
383 
384     if (sparse_encode) {
385       type_header->entryCount = util::HostToDevice32(entries->size());
386       type_header->flags |= ResTable_type::FLAG_SPARSE;
387       ResTable_sparseTypeEntry* indices =
388           type_writer.NextBlock<ResTable_sparseTypeEntry>(entries->size());
389       for (size_t i = 0; i < num_total_entries; i++) {
390         if (offsets[i] != ResTable_type::NO_ENTRY) {
391           CHECK((offsets[i] & 0x03) == 0);
392           indices->idx = util::HostToDevice16(i);
393           indices->offset = util::HostToDevice16(offsets[i] / 4u);
394           indices++;
395         }
396       }
397     } else {
398       type_header->entryCount = util::HostToDevice32(num_total_entries);
399       uint32_t* indices = type_writer.NextBlock<uint32_t>(num_total_entries);
400       for (size_t i = 0; i < num_total_entries; i++) {
401         indices[i] = util::HostToDevice32(offsets[i]);
402       }
403     }
404 
405     type_header->entriesStart = util::HostToDevice32(type_writer.size());
406     type_writer.buffer()->AppendBuffer(std::move(values_buffer));
407     type_writer.Finish();
408     return true;
409   }
410 
FlattenAliases(BigBuffer * buffer)411   bool FlattenAliases(BigBuffer* buffer) {
412     if (aliases_.empty()) {
413       return true;
414     }
415 
416     ChunkWriter alias_writer(buffer);
417     auto header =
418         alias_writer.StartChunk<ResTable_staged_alias_header>(RES_TABLE_STAGED_ALIAS_TYPE);
419     header->count = util::HostToDevice32(aliases_.size());
420 
421     auto mapping = alias_writer.NextBlock<ResTable_staged_alias_entry>(aliases_.size());
422     for (auto& p : aliases_) {
423       mapping->stagedResId = util::HostToDevice32(p.first);
424       mapping->finalizedResId = util::HostToDevice32(p.second);
425       ++mapping;
426     }
427     alias_writer.Finish();
428     return true;
429   }
430 
FlattenOverlayable(BigBuffer * buffer)431   bool FlattenOverlayable(BigBuffer* buffer) {
432     std::set<ResourceId> seen_ids;
433     std::map<std::string, OverlayableChunk> overlayable_chunks;
434 
435     CHECK(bool(package_.id)) << "package must have an ID set when flattening <overlayable>";
436     for (auto& type : package_.types) {
437       CHECK(bool(type.id)) << "type must have an ID set when flattening <overlayable>";
438       for (auto& entry : type.entries) {
439         CHECK(bool(type.id)) << "entry must have an ID set when flattening <overlayable>";
440         if (!entry.overlayable_item) {
441           continue;
442         }
443 
444         const OverlayableItem& item = entry.overlayable_item.value();
445 
446         // Resource ids should only appear once in the resource table
447         ResourceId id = android::make_resid(package_.id.value(), type.id.value(), entry.id.value());
448         CHECK(seen_ids.find(id) == seen_ids.end())
449             << "multiple overlayable definitions found for resource "
450             << ResourceName(package_.name, type.type, entry.name).to_string();
451         seen_ids.insert(id);
452 
453         // Find the overlayable chunk with the specified name
454         OverlayableChunk* overlayable_chunk = nullptr;
455         auto iter = overlayable_chunks.find(item.overlayable->name);
456         if (iter == overlayable_chunks.end()) {
457           OverlayableChunk chunk{item.overlayable->actor, item.overlayable->source};
458           overlayable_chunk =
459               &overlayable_chunks.insert({item.overlayable->name, chunk}).first->second;
460         } else {
461           OverlayableChunk& chunk = iter->second;
462           if (!(chunk.source == item.overlayable->source)) {
463             // The name of an overlayable set of resources must be unique
464             context_->GetDiagnostics()->Error(DiagMessage(item.overlayable->source)
465                                                   << "duplicate overlayable name"
466                                                   << item.overlayable->name << "'");
467             context_->GetDiagnostics()->Error(DiagMessage(chunk.source)
468                                                   << "previous declaration here");
469             return false;
470           }
471 
472           CHECK(chunk.actor == item.overlayable->actor);
473           overlayable_chunk = &chunk;
474         }
475 
476         if (item.policies == 0) {
477           context_->GetDiagnostics()->Error(DiagMessage(item.overlayable->source)
478                                             << "overlayable " << entry.name
479                                             << " does not specify policy");
480           return false;
481         }
482 
483         auto policy = overlayable_chunk->policy_ids.find(item.policies);
484         if (policy != overlayable_chunk->policy_ids.end()) {
485           policy->second.insert(id);
486         } else {
487           overlayable_chunk->policy_ids.insert(
488               std::make_pair(item.policies, std::set<ResourceId>{id}));
489         }
490       }
491     }
492 
493     for (auto& overlayable_pair : overlayable_chunks) {
494       std::string name = overlayable_pair.first;
495       OverlayableChunk& overlayable = overlayable_pair.second;
496 
497       // Write the header of the overlayable chunk
498       ChunkWriter overlayable_writer(buffer);
499       auto* overlayable_type =
500           overlayable_writer.StartChunk<ResTable_overlayable_header>(RES_TABLE_OVERLAYABLE_TYPE);
501       if (name.size() >= arraysize(overlayable_type->name)) {
502         diag_->Error(DiagMessage() << "overlayable name '" << name
503                                    << "' exceeds maximum length ("
504                                    << arraysize(overlayable_type->name)
505                                    << " utf16 characters)");
506         return false;
507       }
508       strcpy16_htod(overlayable_type->name, arraysize(overlayable_type->name),
509                     util::Utf8ToUtf16(name));
510 
511       if (overlayable.actor.size() >= arraysize(overlayable_type->actor)) {
512         diag_->Error(DiagMessage() << "overlayable name '" << overlayable.actor
513                                    << "' exceeds maximum length ("
514                                    << arraysize(overlayable_type->actor)
515                                    << " utf16 characters)");
516         return false;
517       }
518       strcpy16_htod(overlayable_type->actor, arraysize(overlayable_type->actor),
519                     util::Utf8ToUtf16(overlayable.actor));
520 
521       // Write each policy block for the overlayable
522       for (auto& policy_ids : overlayable.policy_ids) {
523         ChunkWriter policy_writer(buffer);
524         auto* policy_type = policy_writer.StartChunk<ResTable_overlayable_policy_header>(
525             RES_TABLE_OVERLAYABLE_POLICY_TYPE);
526         policy_type->policy_flags =
527             static_cast<PolicyFlags>(util::HostToDevice32(static_cast<uint32_t>(policy_ids.first)));
528         policy_type->entry_count = util::HostToDevice32(static_cast<uint32_t>(
529                                                             policy_ids.second.size()));
530         // Write the ids after the policy header
531         auto* id_block = policy_writer.NextBlock<ResTable_ref>(policy_ids.second.size());
532         for (const ResourceId& id : policy_ids.second) {
533           id_block->ident = util::HostToDevice32(id.id);
534           id_block++;
535         }
536         policy_writer.Finish();
537       }
538       overlayable_writer.Finish();
539     }
540 
541     return true;
542   }
543 
FlattenTypeSpec(const ResourceTableTypeView & type,const std::vector<ResourceTableEntryView> & sorted_entries,BigBuffer * buffer)544   bool FlattenTypeSpec(const ResourceTableTypeView& type,
545                        const std::vector<ResourceTableEntryView>& sorted_entries,
546                        BigBuffer* buffer) {
547     ChunkWriter type_spec_writer(buffer);
548     ResTable_typeSpec* spec_header =
549         type_spec_writer.StartChunk<ResTable_typeSpec>(RES_TABLE_TYPE_SPEC_TYPE);
550     spec_header->id = type.id.value();
551 
552     if (sorted_entries.empty()) {
553       type_spec_writer.Finish();
554       return true;
555     }
556 
557     // We can't just take the size of the vector. There may be holes in the
558     // entry ID space.
559     // Since the entries are sorted by ID, the last one will be the biggest.
560     const size_t num_entries = sorted_entries.back().id.value() + 1;
561 
562     spec_header->entryCount = util::HostToDevice32(num_entries);
563 
564     // Reserve space for the masks of each resource in this type. These
565     // show for which configuration axis the resource changes.
566     uint32_t* config_masks = type_spec_writer.NextBlock<uint32_t>(num_entries);
567 
568     for (const ResourceTableEntryView& entry : sorted_entries) {
569       const uint16_t entry_id = entry.id.value();
570 
571       // Populate the config masks for this entry.
572       uint32_t& entry_config_masks = config_masks[entry_id];
573       if (entry.visibility.level == Visibility::Level::kPublic) {
574         entry_config_masks |= util::HostToDevice32(ResTable_typeSpec::SPEC_PUBLIC);
575       }
576       if (entry.visibility.staged_api) {
577         entry_config_masks |= util::HostToDevice32(ResTable_typeSpec::SPEC_STAGED_API);
578       }
579 
580       const size_t config_count = entry.values.size();
581       for (size_t i = 0; i < config_count; i++) {
582         const ConfigDescription& config = entry.values[i]->config;
583         for (size_t j = i + 1; j < config_count; j++) {
584           config_masks[entry_id] |= util::HostToDevice32(config.diff(entry.values[j]->config));
585         }
586       }
587     }
588     type_spec_writer.Finish();
589     return true;
590   }
591 
FlattenTypes(BigBuffer * buffer)592   bool FlattenTypes(BigBuffer* buffer) {
593     size_t expected_type_id = 1;
594     for (const ResourceTableTypeView& type : package_.types) {
595       if (type.type == ResourceType::kStyleable || type.type == ResourceType::kMacro) {
596         // Styleables and macros are not real resource types.
597         continue;
598       }
599 
600       // If there is a gap in the type IDs, fill in the StringPool
601       // with empty values until we reach the ID we expect.
602       while (type.id.value() > expected_type_id) {
603         std::stringstream type_name;
604         type_name << "?" << expected_type_id;
605         type_pool_.MakeRef(type_name.str());
606         expected_type_id++;
607       }
608       expected_type_id++;
609       type_pool_.MakeRef(to_string(type.type));
610 
611       if (!FlattenTypeSpec(type, type.entries, buffer)) {
612         return false;
613       }
614 
615       // Since the entries are sorted by ID, the last ID will be the largest.
616       const size_t num_entries = type.entries.back().id.value() + 1;
617 
618       // The binary resource table lists resource entries for each
619       // configuration.
620       // We store them inverted, where a resource entry lists the values for
621       // each
622       // configuration available. Here we reverse this to match the binary
623       // table.
624       std::map<ConfigDescription, std::vector<FlatEntry>> config_to_entry_list_map;
625 
626       // hardcoded string uses characters which make it an invalid resource name
627       const std::string obfuscated_resource_name = "0_resource_name_obfuscated";
628 
629       for (const ResourceTableEntryView& entry : type.entries) {
630         if (entry.staged_id) {
631           aliases_.insert(std::make_pair(
632               entry.staged_id.value().id.id,
633               ResourceId(package_.id.value(), type.id.value(), entry.id.value()).id));
634         }
635 
636         uint32_t local_key_index;
637         ResourceName resource_name({}, type.type, entry.name);
638         if (!collapse_key_stringpool_ ||
639             name_collapse_exemptions_.find(resource_name) != name_collapse_exemptions_.end()) {
640           local_key_index = (uint32_t)key_pool_.MakeRef(entry.name).index();
641         } else {
642           // resource isn't exempt from collapse, add it as obfuscated value
643           local_key_index = (uint32_t)key_pool_.MakeRef(obfuscated_resource_name).index();
644         }
645         // Group values by configuration.
646         for (auto& config_value : entry.values) {
647           config_to_entry_list_map[config_value->config].push_back(
648               FlatEntry{&entry, config_value->value.get(), local_key_index});
649         }
650       }
651 
652       // Flatten a configuration value.
653       for (auto& entry : config_to_entry_list_map) {
654         if (!FlattenConfig(type, entry.first, num_entries, &entry.second, buffer)) {
655           return false;
656         }
657       }
658     }
659     return true;
660   }
661 
FlattenLibrarySpec(BigBuffer * buffer)662   void FlattenLibrarySpec(BigBuffer* buffer) {
663     ChunkWriter lib_writer(buffer);
664     ResTable_lib_header* lib_header =
665         lib_writer.StartChunk<ResTable_lib_header>(RES_TABLE_LIBRARY_TYPE);
666 
667     const size_t num_entries = (package_.id.value() == 0x00 ? 1 : 0) + shared_libs_->size();
668     CHECK(num_entries > 0);
669 
670     lib_header->count = util::HostToDevice32(num_entries);
671 
672     ResTable_lib_entry* lib_entry = buffer->NextBlock<ResTable_lib_entry>(num_entries);
673     if (package_.id.value() == 0x00) {
674       // Add this package
675       lib_entry->packageId = util::HostToDevice32(0x00);
676       strcpy16_htod(lib_entry->packageName, arraysize(lib_entry->packageName),
677                     util::Utf8ToUtf16(package_.name));
678       ++lib_entry;
679     }
680 
681     for (auto& map_entry : *shared_libs_) {
682       lib_entry->packageId = util::HostToDevice32(map_entry.first);
683       strcpy16_htod(lib_entry->packageName, arraysize(lib_entry->packageName),
684                     util::Utf8ToUtf16(map_entry.second));
685       ++lib_entry;
686     }
687     lib_writer.Finish();
688   }
689 
690   IAaptContext* context_;
691   IDiagnostics* diag_;
692   const ResourceTablePackageView package_;
693   const std::map<size_t, std::string>* shared_libs_;
694   bool use_sparse_entries_;
695   StringPool type_pool_;
696   StringPool key_pool_;
697   bool collapse_key_stringpool_;
698   const std::set<ResourceName>& name_collapse_exemptions_;
699   std::map<uint32_t, uint32_t> aliases_;
700 };
701 
702 }  // namespace
703 
Consume(IAaptContext * context,ResourceTable * table)704 bool TableFlattener::Consume(IAaptContext* context, ResourceTable* table) {
705   TRACE_CALL();
706   // We must do this before writing the resources, since the string pool IDs may change.
707   table->string_pool.Prune();
708   table->string_pool.Sort([](const StringPool::Context& a, const StringPool::Context& b) -> int {
709     int diff = util::compare(a.priority, b.priority);
710     if (diff == 0) {
711       diff = a.config.compare(b.config);
712     }
713     return diff;
714   });
715 
716   // Write the ResTable header.
717   const auto& table_view =
718       table->GetPartitionedView(ResourceTableViewOptions{.create_alias_entries = true});
719   ChunkWriter table_writer(buffer_);
720   ResTable_header* table_header = table_writer.StartChunk<ResTable_header>(RES_TABLE_TYPE);
721   table_header->packageCount = util::HostToDevice32(table_view.packages.size());
722 
723   // Flatten the values string pool.
724   StringPool::FlattenUtf8(table_writer.buffer(), table->string_pool,
725       context->GetDiagnostics());
726 
727   BigBuffer package_buffer(1024);
728 
729   // Flatten each package.
730   for (auto& package : table_view.packages) {
731     if (context->GetPackageType() == PackageType::kApp) {
732       // Write a self mapping entry for this package if the ID is non-standard (0x7f).
733       CHECK((bool)package.id) << "Resource ids have not been assigned before flattening the table";
734       const uint8_t package_id = package.id.value();
735       if (package_id != kFrameworkPackageId && package_id != kAppPackageId) {
736         auto result = table->included_packages_.insert({package_id, package.name});
737         if (!result.second && result.first->second != package.name) {
738           // A mapping for this package ID already exists, and is a different package. Error!
739           context->GetDiagnostics()->Error(
740               DiagMessage() << android::base::StringPrintf(
741                   "can't map package ID %02x to '%s'. Already mapped to '%s'", package_id,
742                   package.name.c_str(), result.first->second.c_str()));
743           return false;
744         }
745       }
746     }
747 
748     PackageFlattener flattener(context, package, &table->included_packages_,
749                                options_.use_sparse_entries, options_.collapse_key_stringpool,
750                                options_.name_collapse_exemptions);
751     if (!flattener.FlattenPackage(&package_buffer)) {
752       return false;
753     }
754   }
755 
756   // Finally merge all the packages into the main buffer.
757   table_writer.buffer()->AppendBuffer(std::move(package_buffer));
758   table_writer.Finish();
759   return true;
760 }
761 
762 }  // namespace aapt
763