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      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 "ResourceUtils.h"
     18 
     19 #include <sstream>
     20 
     21 #include "android-base/stringprintf.h"
     22 #include "androidfw/ResourceTypes.h"
     23 #include "androidfw/ResourceUtils.h"
     24 
     25 #include "NameMangler.h"
     26 #include "SdkConstants.h"
     27 #include "format/binary/ResourceTypeExtensions.h"
     28 #include "text/Unicode.h"
     29 #include "text/Utf8Iterator.h"
     30 #include "util/Files.h"
     31 #include "util/Util.h"
     32 
     33 using ::aapt::text::Utf8Iterator;
     34 using ::android::StringPiece;
     35 using ::android::StringPiece16;
     36 using ::android::base::StringPrintf;
     37 
     38 namespace aapt {
     39 namespace ResourceUtils {
     40 
     41 Maybe<ResourceName> ToResourceName(
     42     const android::ResTable::resource_name& name_in) {
     43   ResourceName name_out;
     44   if (!name_in.package) {
     45     return {};
     46   }
     47 
     48   name_out.package =
     49       util::Utf16ToUtf8(StringPiece16(name_in.package, name_in.packageLen));
     50 
     51   const ResourceType* type;
     52   if (name_in.type) {
     53     type = ParseResourceType(
     54         util::Utf16ToUtf8(StringPiece16(name_in.type, name_in.typeLen)));
     55   } else if (name_in.type8) {
     56     type = ParseResourceType(StringPiece(name_in.type8, name_in.typeLen));
     57   } else {
     58     return {};
     59   }
     60 
     61   if (!type) {
     62     return {};
     63   }
     64 
     65   name_out.type = *type;
     66 
     67   if (name_in.name) {
     68     name_out.entry =
     69         util::Utf16ToUtf8(StringPiece16(name_in.name, name_in.nameLen));
     70   } else if (name_in.name8) {
     71     name_out.entry.assign(name_in.name8, name_in.nameLen);
     72   } else {
     73     return {};
     74   }
     75   return name_out;
     76 }
     77 
     78 bool ParseResourceName(const StringPiece& str, ResourceNameRef* out_ref,
     79                        bool* out_private) {
     80   if (str.empty()) {
     81     return false;
     82   }
     83 
     84   size_t offset = 0;
     85   bool priv = false;
     86   if (str.data()[0] == '*') {
     87     priv = true;
     88     offset = 1;
     89   }
     90 
     91   StringPiece package;
     92   StringPiece type;
     93   StringPiece entry;
     94   if (!android::ExtractResourceName(str.substr(offset, str.size() - offset), &package, &type,
     95                                     &entry)) {
     96     return false;
     97   }
     98 
     99   const ResourceType* parsed_type = ParseResourceType(type);
    100   if (!parsed_type) {
    101     return false;
    102   }
    103 
    104   if (entry.empty()) {
    105     return false;
    106   }
    107 
    108   if (out_ref) {
    109     out_ref->package = package;
    110     out_ref->type = *parsed_type;
    111     out_ref->entry = entry;
    112   }
    113 
    114   if (out_private) {
    115     *out_private = priv;
    116   }
    117   return true;
    118 }
    119 
    120 bool ParseReference(const StringPiece& str, ResourceNameRef* out_ref,
    121                     bool* out_create, bool* out_private) {
    122   StringPiece trimmed_str(util::TrimWhitespace(str));
    123   if (trimmed_str.empty()) {
    124     return false;
    125   }
    126 
    127   bool create = false;
    128   bool priv = false;
    129   if (trimmed_str.data()[0] == '@') {
    130     size_t offset = 1;
    131     if (trimmed_str.data()[1] == '+') {
    132       create = true;
    133       offset += 1;
    134     }
    135 
    136     ResourceNameRef name;
    137     if (!ParseResourceName(
    138             trimmed_str.substr(offset, trimmed_str.size() - offset), &name,
    139             &priv)) {
    140       return false;
    141     }
    142 
    143     if (create && priv) {
    144       return false;
    145     }
    146 
    147     if (create && name.type != ResourceType::kId) {
    148       return false;
    149     }
    150 
    151     if (out_ref) {
    152       *out_ref = name;
    153     }
    154 
    155     if (out_create) {
    156       *out_create = create;
    157     }
    158 
    159     if (out_private) {
    160       *out_private = priv;
    161     }
    162     return true;
    163   }
    164   return false;
    165 }
    166 
    167 bool IsReference(const StringPiece& str) {
    168   return ParseReference(str, nullptr, nullptr, nullptr);
    169 }
    170 
    171 bool ParseAttributeReference(const StringPiece& str, ResourceNameRef* out_ref) {
    172   StringPiece trimmed_str(util::TrimWhitespace(str));
    173   if (trimmed_str.empty()) {
    174     return false;
    175   }
    176 
    177   if (*trimmed_str.data() == '?') {
    178     StringPiece package;
    179     StringPiece type;
    180     StringPiece entry;
    181     if (!android::ExtractResourceName(trimmed_str.substr(1, trimmed_str.size() - 1), &package,
    182                                       &type, &entry)) {
    183       return false;
    184     }
    185 
    186     if (!type.empty() && type != "attr") {
    187       return false;
    188     }
    189 
    190     if (entry.empty()) {
    191       return false;
    192     }
    193 
    194     if (out_ref) {
    195       out_ref->package = package;
    196       out_ref->type = ResourceType::kAttr;
    197       out_ref->entry = entry;
    198     }
    199     return true;
    200   }
    201   return false;
    202 }
    203 
    204 bool IsAttributeReference(const StringPiece& str) {
    205   return ParseAttributeReference(str, nullptr);
    206 }
    207 
    208 /*
    209  * Style parent's are a bit different. We accept the following formats:
    210  *
    211  * @[[*]package:][style/]<entry>
    212  * ?[[*]package:]style/<entry>
    213  * <[*]package>:[style/]<entry>
    214  * [[*]package:style/]<entry>
    215  */
    216 Maybe<Reference> ParseStyleParentReference(const StringPiece& str,
    217                                            std::string* out_error) {
    218   if (str.empty()) {
    219     return {};
    220   }
    221 
    222   StringPiece name = str;
    223 
    224   bool has_leading_identifiers = false;
    225   bool private_ref = false;
    226 
    227   // Skip over these identifiers. A style's parent is a normal reference.
    228   if (name.data()[0] == '@' || name.data()[0] == '?') {
    229     has_leading_identifiers = true;
    230     name = name.substr(1, name.size() - 1);
    231   }
    232 
    233   if (name.data()[0] == '*') {
    234     private_ref = true;
    235     name = name.substr(1, name.size() - 1);
    236   }
    237 
    238   ResourceNameRef ref;
    239   ref.type = ResourceType::kStyle;
    240 
    241   StringPiece type_str;
    242   android::ExtractResourceName(name, &ref.package, &type_str, &ref.entry);
    243   if (!type_str.empty()) {
    244     // If we have a type, make sure it is a Style.
    245     const ResourceType* parsed_type = ParseResourceType(type_str);
    246     if (!parsed_type || *parsed_type != ResourceType::kStyle) {
    247       std::stringstream err;
    248       err << "invalid resource type '" << type_str << "' for parent of style";
    249       *out_error = err.str();
    250       return {};
    251     }
    252   }
    253 
    254   if (!has_leading_identifiers && ref.package.empty() && !type_str.empty()) {
    255     std::stringstream err;
    256     err << "invalid parent reference '" << str << "'";
    257     *out_error = err.str();
    258     return {};
    259   }
    260 
    261   Reference result(ref);
    262   result.private_reference = private_ref;
    263   return result;
    264 }
    265 
    266 Maybe<Reference> ParseXmlAttributeName(const StringPiece& str) {
    267   StringPiece trimmed_str = util::TrimWhitespace(str);
    268   const char* start = trimmed_str.data();
    269   const char* const end = start + trimmed_str.size();
    270   const char* p = start;
    271 
    272   Reference ref;
    273   if (p != end && *p == '*') {
    274     ref.private_reference = true;
    275     start++;
    276     p++;
    277   }
    278 
    279   StringPiece package;
    280   StringPiece name;
    281   while (p != end) {
    282     if (*p == ':') {
    283       package = StringPiece(start, p - start);
    284       name = StringPiece(p + 1, end - (p + 1));
    285       break;
    286     }
    287     p++;
    288   }
    289 
    290   ref.name = ResourceName(package, ResourceType::kAttr, name.empty() ? trimmed_str : name);
    291   return Maybe<Reference>(std::move(ref));
    292 }
    293 
    294 std::unique_ptr<Reference> TryParseReference(const StringPiece& str,
    295                                              bool* out_create) {
    296   ResourceNameRef ref;
    297   bool private_ref = false;
    298   if (ParseReference(str, &ref, out_create, &private_ref)) {
    299     std::unique_ptr<Reference> value = util::make_unique<Reference>(ref);
    300     value->private_reference = private_ref;
    301     return value;
    302   }
    303 
    304   if (ParseAttributeReference(str, &ref)) {
    305     if (out_create) {
    306       *out_create = false;
    307     }
    308     return util::make_unique<Reference>(ref, Reference::Type::kAttribute);
    309   }
    310   return {};
    311 }
    312 
    313 std::unique_ptr<Item> TryParseNullOrEmpty(const StringPiece& str) {
    314   const StringPiece trimmed_str(util::TrimWhitespace(str));
    315   if (trimmed_str == "@null") {
    316     return MakeNull();
    317   } else if (trimmed_str == "@empty") {
    318     return MakeEmpty();
    319   }
    320   return {};
    321 }
    322 
    323 std::unique_ptr<Reference> MakeNull() {
    324   // TYPE_NULL with data set to 0 is interpreted by the runtime as an error.
    325   // Instead we set the data type to TYPE_REFERENCE with a value of 0.
    326   return util::make_unique<Reference>();
    327 }
    328 
    329 std::unique_ptr<BinaryPrimitive> MakeEmpty() {
    330   return util::make_unique<BinaryPrimitive>(android::Res_value::TYPE_NULL,
    331                                             android::Res_value::DATA_NULL_EMPTY);
    332 }
    333 
    334 std::unique_ptr<BinaryPrimitive> TryParseEnumSymbol(const Attribute* enum_attr,
    335                                                     const StringPiece& str) {
    336   StringPiece trimmed_str(util::TrimWhitespace(str));
    337   for (const Attribute::Symbol& symbol : enum_attr->symbols) {
    338     // Enum symbols are stored as @package:id/symbol resources,
    339     // so we need to match against the 'entry' part of the identifier.
    340     const ResourceName& enum_symbol_resource_name = symbol.symbol.name.value();
    341     if (trimmed_str == enum_symbol_resource_name.entry) {
    342       android::Res_value value = {};
    343       value.dataType = android::Res_value::TYPE_INT_DEC;
    344       value.data = symbol.value;
    345       return util::make_unique<BinaryPrimitive>(value);
    346     }
    347   }
    348   return {};
    349 }
    350 
    351 std::unique_ptr<BinaryPrimitive> TryParseFlagSymbol(const Attribute* flag_attr,
    352                                                     const StringPiece& str) {
    353   android::Res_value flags = {};
    354   flags.dataType = android::Res_value::TYPE_INT_HEX;
    355   flags.data = 0u;
    356 
    357   if (util::TrimWhitespace(str).empty()) {
    358     // Empty string is a valid flag (0).
    359     return util::make_unique<BinaryPrimitive>(flags);
    360   }
    361 
    362   for (StringPiece part : util::Tokenize(str, '|')) {
    363     StringPiece trimmed_part = util::TrimWhitespace(part);
    364 
    365     bool flag_set = false;
    366     for (const Attribute::Symbol& symbol : flag_attr->symbols) {
    367       // Flag symbols are stored as @package:id/symbol resources,
    368       // so we need to match against the 'entry' part of the identifier.
    369       const ResourceName& flag_symbol_resource_name =
    370           symbol.symbol.name.value();
    371       if (trimmed_part == flag_symbol_resource_name.entry) {
    372         flags.data |= symbol.value;
    373         flag_set = true;
    374         break;
    375       }
    376     }
    377 
    378     if (!flag_set) {
    379       return {};
    380     }
    381   }
    382   return util::make_unique<BinaryPrimitive>(flags);
    383 }
    384 
    385 static uint32_t ParseHex(char c, bool* out_error) {
    386   if (c >= '0' && c <= '9') {
    387     return c - '0';
    388   } else if (c >= 'a' && c <= 'f') {
    389     return c - 'a' + 0xa;
    390   } else if (c >= 'A' && c <= 'F') {
    391     return c - 'A' + 0xa;
    392   } else {
    393     *out_error = true;
    394     return 0xffffffffu;
    395   }
    396 }
    397 
    398 std::unique_ptr<BinaryPrimitive> TryParseColor(const StringPiece& str) {
    399   StringPiece color_str(util::TrimWhitespace(str));
    400   const char* start = color_str.data();
    401   const size_t len = color_str.size();
    402   if (len == 0 || start[0] != '#') {
    403     return {};
    404   }
    405 
    406   android::Res_value value = {};
    407   bool error = false;
    408   if (len == 4) {
    409     value.dataType = android::Res_value::TYPE_INT_COLOR_RGB4;
    410     value.data = 0xff000000u;
    411     value.data |= ParseHex(start[1], &error) << 20;
    412     value.data |= ParseHex(start[1], &error) << 16;
    413     value.data |= ParseHex(start[2], &error) << 12;
    414     value.data |= ParseHex(start[2], &error) << 8;
    415     value.data |= ParseHex(start[3], &error) << 4;
    416     value.data |= ParseHex(start[3], &error);
    417   } else if (len == 5) {
    418     value.dataType = android::Res_value::TYPE_INT_COLOR_ARGB4;
    419     value.data |= ParseHex(start[1], &error) << 28;
    420     value.data |= ParseHex(start[1], &error) << 24;
    421     value.data |= ParseHex(start[2], &error) << 20;
    422     value.data |= ParseHex(start[2], &error) << 16;
    423     value.data |= ParseHex(start[3], &error) << 12;
    424     value.data |= ParseHex(start[3], &error) << 8;
    425     value.data |= ParseHex(start[4], &error) << 4;
    426     value.data |= ParseHex(start[4], &error);
    427   } else if (len == 7) {
    428     value.dataType = android::Res_value::TYPE_INT_COLOR_RGB8;
    429     value.data = 0xff000000u;
    430     value.data |= ParseHex(start[1], &error) << 20;
    431     value.data |= ParseHex(start[2], &error) << 16;
    432     value.data |= ParseHex(start[3], &error) << 12;
    433     value.data |= ParseHex(start[4], &error) << 8;
    434     value.data |= ParseHex(start[5], &error) << 4;
    435     value.data |= ParseHex(start[6], &error);
    436   } else if (len == 9) {
    437     value.dataType = android::Res_value::TYPE_INT_COLOR_ARGB8;
    438     value.data |= ParseHex(start[1], &error) << 28;
    439     value.data |= ParseHex(start[2], &error) << 24;
    440     value.data |= ParseHex(start[3], &error) << 20;
    441     value.data |= ParseHex(start[4], &error) << 16;
    442     value.data |= ParseHex(start[5], &error) << 12;
    443     value.data |= ParseHex(start[6], &error) << 8;
    444     value.data |= ParseHex(start[7], &error) << 4;
    445     value.data |= ParseHex(start[8], &error);
    446   } else {
    447     return {};
    448   }
    449   return error ? std::unique_ptr<BinaryPrimitive>()
    450                : util::make_unique<BinaryPrimitive>(value);
    451 }
    452 
    453 Maybe<bool> ParseBool(const StringPiece& str) {
    454   StringPiece trimmed_str(util::TrimWhitespace(str));
    455   if (trimmed_str == "true" || trimmed_str == "TRUE" || trimmed_str == "True") {
    456     return Maybe<bool>(true);
    457   } else if (trimmed_str == "false" || trimmed_str == "FALSE" ||
    458              trimmed_str == "False") {
    459     return Maybe<bool>(false);
    460   }
    461   return {};
    462 }
    463 
    464 Maybe<uint32_t> ParseInt(const StringPiece& str) {
    465   std::u16string str16 = util::Utf8ToUtf16(str);
    466   android::Res_value value;
    467   if (android::ResTable::stringToInt(str16.data(), str16.size(), &value)) {
    468     return value.data;
    469   }
    470   return {};
    471 }
    472 
    473 Maybe<ResourceId> ParseResourceId(const StringPiece& str) {
    474   StringPiece trimmed_str(util::TrimWhitespace(str));
    475 
    476   std::u16string str16 = util::Utf8ToUtf16(trimmed_str);
    477   android::Res_value value;
    478   if (android::ResTable::stringToInt(str16.data(), str16.size(), &value)) {
    479     if (value.dataType == android::Res_value::TYPE_INT_HEX) {
    480       ResourceId id(value.data);
    481       if (id.is_valid_dynamic()) {
    482         return id;
    483       }
    484     }
    485   }
    486   return {};
    487 }
    488 
    489 Maybe<int> ParseSdkVersion(const StringPiece& str) {
    490   StringPiece trimmed_str(util::TrimWhitespace(str));
    491 
    492   std::u16string str16 = util::Utf8ToUtf16(trimmed_str);
    493   android::Res_value value;
    494   if (android::ResTable::stringToInt(str16.data(), str16.size(), &value)) {
    495     return static_cast<int>(value.data);
    496   }
    497 
    498   // Try parsing the code name.
    499   std::pair<StringPiece, int> entry = GetDevelopmentSdkCodeNameAndVersion();
    500   if (entry.first == trimmed_str) {
    501     return entry.second;
    502   }
    503   return {};
    504 }
    505 
    506 std::unique_ptr<BinaryPrimitive> TryParseBool(const StringPiece& str) {
    507   if (Maybe<bool> maybe_result = ParseBool(str)) {
    508     const uint32_t data = maybe_result.value() ? 0xffffffffu : 0u;
    509     return util::make_unique<BinaryPrimitive>(android::Res_value::TYPE_INT_BOOLEAN, data);
    510   }
    511   return {};
    512 }
    513 
    514 std::unique_ptr<BinaryPrimitive> MakeBool(bool val) {
    515   return util::make_unique<BinaryPrimitive>(android::Res_value::TYPE_INT_BOOLEAN,
    516                                             val ? 0xffffffffu : 0u);
    517 }
    518 
    519 std::unique_ptr<BinaryPrimitive> TryParseInt(const StringPiece& str) {
    520   std::u16string str16 = util::Utf8ToUtf16(util::TrimWhitespace(str));
    521   android::Res_value value;
    522   if (!android::ResTable::stringToInt(str16.data(), str16.size(), &value)) {
    523     return {};
    524   }
    525   return util::make_unique<BinaryPrimitive>(value);
    526 }
    527 
    528 std::unique_ptr<BinaryPrimitive> MakeInt(uint32_t val) {
    529   return util::make_unique<BinaryPrimitive>(android::Res_value::TYPE_INT_DEC, val);
    530 }
    531 
    532 std::unique_ptr<BinaryPrimitive> TryParseFloat(const StringPiece& str) {
    533   std::u16string str16 = util::Utf8ToUtf16(util::TrimWhitespace(str));
    534   android::Res_value value;
    535   if (!android::ResTable::stringToFloat(str16.data(), str16.size(), &value)) {
    536     return {};
    537   }
    538   return util::make_unique<BinaryPrimitive>(value);
    539 }
    540 
    541 uint32_t AndroidTypeToAttributeTypeMask(uint16_t type) {
    542   switch (type) {
    543     case android::Res_value::TYPE_NULL:
    544     case android::Res_value::TYPE_REFERENCE:
    545     case android::Res_value::TYPE_ATTRIBUTE:
    546     case android::Res_value::TYPE_DYNAMIC_REFERENCE:
    547     case android::Res_value::TYPE_DYNAMIC_ATTRIBUTE:
    548       return android::ResTable_map::TYPE_REFERENCE;
    549 
    550     case android::Res_value::TYPE_STRING:
    551       return android::ResTable_map::TYPE_STRING;
    552 
    553     case android::Res_value::TYPE_FLOAT:
    554       return android::ResTable_map::TYPE_FLOAT;
    555 
    556     case android::Res_value::TYPE_DIMENSION:
    557       return android::ResTable_map::TYPE_DIMENSION;
    558 
    559     case android::Res_value::TYPE_FRACTION:
    560       return android::ResTable_map::TYPE_FRACTION;
    561 
    562     case android::Res_value::TYPE_INT_DEC:
    563     case android::Res_value::TYPE_INT_HEX:
    564       return android::ResTable_map::TYPE_INTEGER |
    565              android::ResTable_map::TYPE_ENUM |
    566              android::ResTable_map::TYPE_FLAGS;
    567 
    568     case android::Res_value::TYPE_INT_BOOLEAN:
    569       return android::ResTable_map::TYPE_BOOLEAN;
    570 
    571     case android::Res_value::TYPE_INT_COLOR_ARGB8:
    572     case android::Res_value::TYPE_INT_COLOR_RGB8:
    573     case android::Res_value::TYPE_INT_COLOR_ARGB4:
    574     case android::Res_value::TYPE_INT_COLOR_RGB4:
    575       return android::ResTable_map::TYPE_COLOR;
    576 
    577     default:
    578       return 0;
    579   };
    580 }
    581 
    582 std::unique_ptr<Item> TryParseItemForAttribute(
    583     const StringPiece& value, uint32_t type_mask,
    584     const std::function<void(const ResourceName&)>& on_create_reference) {
    585   using android::ResTable_map;
    586 
    587   auto null_or_empty = TryParseNullOrEmpty(value);
    588   if (null_or_empty) {
    589     return null_or_empty;
    590   }
    591 
    592   bool create = false;
    593   auto reference = TryParseReference(value, &create);
    594   if (reference) {
    595     if (create && on_create_reference) {
    596       on_create_reference(reference->name.value());
    597     }
    598     return std::move(reference);
    599   }
    600 
    601   if (type_mask & ResTable_map::TYPE_COLOR) {
    602     // Try parsing this as a color.
    603     auto color = TryParseColor(value);
    604     if (color) {
    605       return std::move(color);
    606     }
    607   }
    608 
    609   if (type_mask & ResTable_map::TYPE_BOOLEAN) {
    610     // Try parsing this as a boolean.
    611     auto boolean = TryParseBool(value);
    612     if (boolean) {
    613       return std::move(boolean);
    614     }
    615   }
    616 
    617   if (type_mask & ResTable_map::TYPE_INTEGER) {
    618     // Try parsing this as an integer.
    619     auto integer = TryParseInt(value);
    620     if (integer) {
    621       return std::move(integer);
    622     }
    623   }
    624 
    625   const uint32_t float_mask =
    626       ResTable_map::TYPE_FLOAT | ResTable_map::TYPE_DIMENSION | ResTable_map::TYPE_FRACTION;
    627   if (type_mask & float_mask) {
    628     // Try parsing this as a float.
    629     auto floating_point = TryParseFloat(value);
    630     if (floating_point) {
    631       if (type_mask & AndroidTypeToAttributeTypeMask(floating_point->value.dataType)) {
    632         return std::move(floating_point);
    633       }
    634     }
    635   }
    636   return {};
    637 }
    638 
    639 /**
    640  * We successively try to parse the string as a resource type that the Attribute
    641  * allows.
    642  */
    643 std::unique_ptr<Item> TryParseItemForAttribute(
    644     const StringPiece& str, const Attribute* attr,
    645     const std::function<void(const ResourceName&)>& on_create_reference) {
    646   using android::ResTable_map;
    647 
    648   const uint32_t type_mask = attr->type_mask;
    649   auto value = TryParseItemForAttribute(str, type_mask, on_create_reference);
    650   if (value) {
    651     return value;
    652   }
    653 
    654   if (type_mask & ResTable_map::TYPE_ENUM) {
    655     // Try parsing this as an enum.
    656     auto enum_value = TryParseEnumSymbol(attr, str);
    657     if (enum_value) {
    658       return std::move(enum_value);
    659     }
    660   }
    661 
    662   if (type_mask & ResTable_map::TYPE_FLAGS) {
    663     // Try parsing this as a flag.
    664     auto flag_value = TryParseFlagSymbol(attr, str);
    665     if (flag_value) {
    666       return std::move(flag_value);
    667     }
    668   }
    669   return {};
    670 }
    671 
    672 std::string BuildResourceFileName(const ResourceFile& res_file, const NameMangler* mangler) {
    673   std::stringstream out;
    674   out << "res/" << res_file.name.type;
    675   if (res_file.config != ConfigDescription{}) {
    676     out << "-" << res_file.config;
    677   }
    678   out << "/";
    679 
    680   if (mangler && mangler->ShouldMangle(res_file.name.package)) {
    681     out << NameMangler::MangleEntry(res_file.name.package, res_file.name.entry);
    682   } else {
    683     out << res_file.name.entry;
    684   }
    685   out << file::GetExtension(res_file.source.path);
    686   return out.str();
    687 }
    688 
    689 std::unique_ptr<Item> ParseBinaryResValue(const ResourceType& type, const ConfigDescription& config,
    690                                           const android::ResStringPool& src_pool,
    691                                           const android::Res_value& res_value,
    692                                           StringPool* dst_pool) {
    693   if (type == ResourceType::kId) {
    694     return util::make_unique<Id>();
    695   }
    696 
    697   const uint32_t data = util::DeviceToHost32(res_value.data);
    698   switch (res_value.dataType) {
    699     case android::Res_value::TYPE_STRING: {
    700       const std::string str = util::GetString(src_pool, data);
    701       const android::ResStringPool_span* spans = src_pool.styleAt(data);
    702 
    703       // Check if the string has a valid style associated with it.
    704       if (spans != nullptr && spans->name.index != android::ResStringPool_span::END) {
    705         StyleString style_str = {str};
    706         while (spans->name.index != android::ResStringPool_span::END) {
    707           style_str.spans.push_back(Span{util::GetString(src_pool, spans->name.index),
    708                                          spans->firstChar, spans->lastChar});
    709           spans++;
    710         }
    711         return util::make_unique<StyledString>(dst_pool->MakeRef(
    712             style_str, StringPool::Context(StringPool::Context::kNormalPriority, config)));
    713       } else {
    714         if (type != ResourceType::kString && util::StartsWith(str, "res/")) {
    715           // This must be a FileReference.
    716           std::unique_ptr<FileReference> file_ref =
    717               util::make_unique<FileReference>(dst_pool->MakeRef(
    718                   str, StringPool::Context(StringPool::Context::kHighPriority, config)));
    719           if (type == ResourceType::kRaw) {
    720             file_ref->type = ResourceFile::Type::kUnknown;
    721           } else if (util::EndsWith(*file_ref->path, ".xml")) {
    722             file_ref->type = ResourceFile::Type::kBinaryXml;
    723           } else if (util::EndsWith(*file_ref->path, ".png")) {
    724             file_ref->type = ResourceFile::Type::kPng;
    725           }
    726           return std::move(file_ref);
    727         }
    728 
    729         // There are no styles associated with this string, so treat it as a simple string.
    730         return util::make_unique<String>(dst_pool->MakeRef(str, StringPool::Context(config)));
    731       }
    732     } break;
    733 
    734     case android::Res_value::TYPE_REFERENCE:
    735     case android::Res_value::TYPE_ATTRIBUTE:
    736     case android::Res_value::TYPE_DYNAMIC_REFERENCE:
    737     case android::Res_value::TYPE_DYNAMIC_ATTRIBUTE: {
    738       Reference::Type ref_type = Reference::Type::kResource;
    739       if (res_value.dataType == android::Res_value::TYPE_ATTRIBUTE ||
    740           res_value.dataType == android::Res_value::TYPE_DYNAMIC_ATTRIBUTE) {
    741         ref_type = Reference::Type::kAttribute;
    742       }
    743 
    744       if (data == 0u) {
    745         // A reference of 0, must be the magic @null reference.
    746         return util::make_unique<Reference>();
    747       }
    748 
    749       // This is a normal reference.
    750       return util::make_unique<Reference>(data, ref_type);
    751     } break;
    752   }
    753 
    754   // Treat this as a raw binary primitive.
    755   return util::make_unique<BinaryPrimitive>(res_value);
    756 }
    757 
    758 // Converts the codepoint to UTF-8 and appends it to the string.
    759 static bool AppendCodepointToUtf8String(char32_t codepoint, std::string* output) {
    760   ssize_t len = utf32_to_utf8_length(&codepoint, 1);
    761   if (len < 0) {
    762     return false;
    763   }
    764 
    765   const size_t start_append_pos = output->size();
    766 
    767   // Make room for the next character.
    768   output->resize(output->size() + len);
    769 
    770   char* dst = &*(output->begin() + start_append_pos);
    771   utf32_to_utf8(&codepoint, 1, dst, len + 1);
    772   return true;
    773 }
    774 
    775 // Reads up to 4 UTF-8 characters that represent a Unicode escape sequence, and appends the
    776 // Unicode codepoint represented by the escape sequence to the string.
    777 static bool AppendUnicodeEscapeSequence(Utf8Iterator* iter, std::string* output) {
    778   char32_t code = 0;
    779   for (size_t i = 0; i < 4 && iter->HasNext(); i++) {
    780     char32_t codepoint = iter->Next();
    781     char32_t a;
    782     if (codepoint >= U'0' && codepoint <= U'9') {
    783       a = codepoint - U'0';
    784     } else if (codepoint >= U'a' && codepoint <= U'f') {
    785       a = codepoint - U'a' + 10;
    786     } else if (codepoint >= U'A' && codepoint <= U'F') {
    787       a = codepoint - U'A' + 10;
    788     } else {
    789       return {};
    790     }
    791     code = (code << 4) | a;
    792   }
    793   return AppendCodepointToUtf8String(code, output);
    794 }
    795 
    796 StringBuilder::StringBuilder(bool preserve_spaces)
    797     : preserve_spaces_(preserve_spaces), quote_(preserve_spaces) {
    798 }
    799 
    800 StringBuilder& StringBuilder::AppendText(const std::string& text) {
    801   if (!error_.empty()) {
    802     return *this;
    803   }
    804 
    805   const size_t previous_len = xml_string_.text.size();
    806   Utf8Iterator iter(text);
    807   while (iter.HasNext()) {
    808     char32_t codepoint = iter.Next();
    809     if (!quote_ && iswspace(codepoint)) {
    810       if (!last_codepoint_was_space_) {
    811         // Emit a space if it's the first.
    812         xml_string_.text += ' ';
    813         last_codepoint_was_space_ = true;
    814       }
    815 
    816       // Keep eating spaces.
    817       continue;
    818     }
    819 
    820     // This is not a space.
    821     last_codepoint_was_space_ = false;
    822 
    823     if (codepoint == U'\\') {
    824       if (iter.HasNext()) {
    825         codepoint = iter.Next();
    826         switch (codepoint) {
    827           case U't':
    828             xml_string_.text += '\t';
    829             break;
    830 
    831           case U'n':
    832             xml_string_.text += '\n';
    833             break;
    834 
    835           case U'#':
    836           case U'@':
    837           case U'?':
    838           case U'"':
    839           case U'\'':
    840           case U'\\':
    841             xml_string_.text += static_cast<char>(codepoint);
    842             break;
    843 
    844           case U'u':
    845             if (!AppendUnicodeEscapeSequence(&iter, &xml_string_.text)) {
    846               error_ =
    847                   StringPrintf("invalid unicode escape sequence in string\n\"%s\"", text.c_str());
    848               return *this;
    849             }
    850             break;
    851 
    852           default:
    853             // Ignore the escape character and just include the codepoint.
    854             AppendCodepointToUtf8String(codepoint, &xml_string_.text);
    855             break;
    856         }
    857       }
    858     } else if (!preserve_spaces_ && codepoint == U'"') {
    859       // Only toggle the quote state when we are not preserving spaces.
    860       quote_ = !quote_;
    861 
    862     } else if (!quote_ && codepoint == U'\'') {
    863       // This should be escaped.
    864       error_ = StringPrintf("unescaped apostrophe in string\n\"%s\"", text.c_str());
    865       return *this;
    866 
    867     } else {
    868       AppendCodepointToUtf8String(codepoint, &xml_string_.text);
    869     }
    870   }
    871 
    872   // Accumulate the added string's UTF-16 length.
    873   const uint8_t* utf8_data = reinterpret_cast<const uint8_t*>(xml_string_.text.c_str());
    874   const size_t utf8_length = xml_string_.text.size();
    875   ssize_t len = utf8_to_utf16_length(utf8_data + previous_len, utf8_length - previous_len);
    876   if (len < 0) {
    877     error_ = StringPrintf("invalid unicode code point in string\n\"%s\"", utf8_data + previous_len);
    878     return *this;
    879   }
    880 
    881   utf16_len_ += static_cast<uint32_t>(len);
    882   return *this;
    883 }
    884 
    885 StringBuilder::SpanHandle StringBuilder::StartSpan(const std::string& name) {
    886   if (!error_.empty()) {
    887     return 0u;
    888   }
    889 
    890   // When we start a span, all state associated with whitespace truncation and quotation is ended.
    891   ResetTextState();
    892   Span span;
    893   span.name = name;
    894   span.first_char = span.last_char = utf16_len_;
    895   xml_string_.spans.push_back(std::move(span));
    896   return xml_string_.spans.size() - 1;
    897 }
    898 
    899 void StringBuilder::EndSpan(SpanHandle handle) {
    900   if (!error_.empty()) {
    901     return;
    902   }
    903 
    904   // When we end a span, all state associated with whitespace truncation and quotation is ended.
    905   ResetTextState();
    906   xml_string_.spans[handle].last_char = utf16_len_ - 1u;
    907 }
    908 
    909 StringBuilder::UntranslatableHandle StringBuilder::StartUntranslatable() {
    910   if (!error_.empty()) {
    911     return 0u;
    912   }
    913 
    914   UntranslatableSection section;
    915   section.start = section.end = xml_string_.text.size();
    916   xml_string_.untranslatable_sections.push_back(section);
    917   return xml_string_.untranslatable_sections.size() - 1;
    918 }
    919 
    920 void StringBuilder::EndUntranslatable(UntranslatableHandle handle) {
    921   if (!error_.empty()) {
    922     return;
    923   }
    924   xml_string_.untranslatable_sections[handle].end = xml_string_.text.size();
    925 }
    926 
    927 FlattenedXmlString StringBuilder::GetFlattenedString() const {
    928   return xml_string_;
    929 }
    930 
    931 std::string StringBuilder::to_string() const {
    932   return xml_string_.text;
    933 }
    934 
    935 StringBuilder::operator bool() const {
    936   return error_.empty();
    937 }
    938 
    939 std::string StringBuilder::GetError() const {
    940   return error_;
    941 }
    942 
    943 void StringBuilder::ResetTextState() {
    944   quote_ = preserve_spaces_;
    945   last_codepoint_was_space_ = false;
    946 }
    947 
    948 }  // namespace ResourceUtils
    949 }  // namespace aapt
    950