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      1 /*
      2  * Copyright (C) 2008 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 <algorithm>
     18 #include <set>
     19 #include <fcntl.h>
     20 #ifdef __linux__
     21 #include <sys/sendfile.h>
     22 #else
     23 #include <sys/socket.h>
     24 #endif
     25 #include <sys/stat.h>
     26 #include <unistd.h>
     27 
     28 #include "base/logging.h"
     29 #include "base/stl_util.h"
     30 #include "base/stringprintf.h"
     31 #include "class_linker.h"
     32 #include "common_throws.h"
     33 #include "dex_file-inl.h"
     34 #include "gc/space/image_space.h"
     35 #include "gc/space/space-inl.h"
     36 #include "image.h"
     37 #include "jni_internal.h"
     38 #include "mirror/class_loader.h"
     39 #include "mirror/object-inl.h"
     40 #include "mirror/string.h"
     41 #include "oat.h"
     42 #include "os.h"
     43 #include "profiler.h"
     44 #include "runtime.h"
     45 #include "scoped_thread_state_change.h"
     46 #include "ScopedFd.h"
     47 #include "ScopedLocalRef.h"
     48 #include "ScopedUtfChars.h"
     49 #include "utils.h"
     50 #include "well_known_classes.h"
     51 #include "zip_archive.h"
     52 
     53 namespace art {
     54 
     55 // A smart pointer that provides read-only access to a Java string's UTF chars.
     56 // Unlike libcore's NullableScopedUtfChars, this will *not* throw NullPointerException if
     57 // passed a null jstring. The correct idiom is:
     58 //
     59 //   NullableScopedUtfChars name(env, javaName);
     60 //   if (env->ExceptionCheck()) {
     61 //       return NULL;
     62 //   }
     63 //   // ... use name.c_str()
     64 //
     65 // TODO: rewrite to get rid of this, or change ScopedUtfChars to offer this option.
     66 class NullableScopedUtfChars {
     67  public:
     68   NullableScopedUtfChars(JNIEnv* env, jstring s) : mEnv(env), mString(s) {
     69     mUtfChars = (s != NULL) ? env->GetStringUTFChars(s, NULL) : NULL;
     70   }
     71 
     72   ~NullableScopedUtfChars() {
     73     if (mUtfChars) {
     74       mEnv->ReleaseStringUTFChars(mString, mUtfChars);
     75     }
     76   }
     77 
     78   const char* c_str() const {
     79     return mUtfChars;
     80   }
     81 
     82   size_t size() const {
     83     return strlen(mUtfChars);
     84   }
     85 
     86   // Element access.
     87   const char& operator[](size_t n) const {
     88     return mUtfChars[n];
     89   }
     90 
     91  private:
     92   JNIEnv* mEnv;
     93   jstring mString;
     94   const char* mUtfChars;
     95 
     96   // Disallow copy and assignment.
     97   NullableScopedUtfChars(const NullableScopedUtfChars&);
     98   void operator=(const NullableScopedUtfChars&);
     99 };
    100 
    101 static jlong DexFile_openDexFileNative(JNIEnv* env, jclass, jstring javaSourceName, jstring javaOutputName, jint) {
    102   ScopedUtfChars sourceName(env, javaSourceName);
    103   if (sourceName.c_str() == NULL) {
    104     return 0;
    105   }
    106   NullableScopedUtfChars outputName(env, javaOutputName);
    107   if (env->ExceptionCheck()) {
    108     return 0;
    109   }
    110 
    111   ClassLinker* linker = Runtime::Current()->GetClassLinker();
    112   std::unique_ptr<std::vector<const DexFile*>> dex_files(new std::vector<const DexFile*>());
    113   std::vector<std::string> error_msgs;
    114 
    115   bool success = linker->OpenDexFilesFromOat(sourceName.c_str(), outputName.c_str(), &error_msgs,
    116                                              dex_files.get());
    117 
    118   if (success || !dex_files->empty()) {
    119     // In the case of non-success, we have not found or could not generate the oat file.
    120     // But we may still have found a dex file that we can use.
    121     return static_cast<jlong>(reinterpret_cast<uintptr_t>(dex_files.release()));
    122   } else {
    123     // The vector should be empty after a failed loading attempt.
    124     DCHECK_EQ(0U, dex_files->size());
    125 
    126     ScopedObjectAccess soa(env);
    127     CHECK(!error_msgs.empty());
    128     // The most important message is at the end. So set up nesting by going forward, which will
    129     // wrap the existing exception as a cause for the following one.
    130     auto it = error_msgs.begin();
    131     auto itEnd = error_msgs.end();
    132     for ( ; it != itEnd; ++it) {
    133       ThrowWrappedIOException("%s", it->c_str());
    134     }
    135 
    136     return 0;
    137   }
    138 }
    139 
    140 static std::vector<const DexFile*>* toDexFiles(jlong dex_file_address, JNIEnv* env) {
    141   std::vector<const DexFile*>* dex_files = reinterpret_cast<std::vector<const DexFile*>*>(
    142       static_cast<uintptr_t>(dex_file_address));
    143   if (UNLIKELY(dex_files == nullptr)) {
    144     ScopedObjectAccess soa(env);
    145     ThrowNullPointerException(NULL, "dex_file == null");
    146   }
    147   return dex_files;
    148 }
    149 
    150 static void DexFile_closeDexFile(JNIEnv* env, jclass, jlong cookie) {
    151   std::unique_ptr<std::vector<const DexFile*>> dex_files(toDexFiles(cookie, env));
    152   if (dex_files.get() == nullptr) {
    153     return;
    154   }
    155   ScopedObjectAccess soa(env);
    156 
    157   size_t index = 0;
    158   for (const DexFile* dex_file : *dex_files) {
    159     if (Runtime::Current()->GetClassLinker()->IsDexFileRegistered(*dex_file)) {
    160       (*dex_files)[index] = nullptr;
    161     }
    162     index++;
    163   }
    164 
    165   STLDeleteElements(dex_files.get());
    166   // Unique_ptr will delete the vector itself.
    167 }
    168 
    169 static jclass DexFile_defineClassNative(JNIEnv* env, jclass, jstring javaName, jobject javaLoader,
    170                                         jlong cookie) {
    171   std::vector<const DexFile*>* dex_files = toDexFiles(cookie, env);
    172   if (dex_files == NULL) {
    173     VLOG(class_linker) << "Failed to find dex_file";
    174     return NULL;
    175   }
    176   ScopedUtfChars class_name(env, javaName);
    177   if (class_name.c_str() == NULL) {
    178     VLOG(class_linker) << "Failed to find class_name";
    179     return NULL;
    180   }
    181   const std::string descriptor(DotToDescriptor(class_name.c_str()));
    182   const size_t hash(ComputeModifiedUtf8Hash(descriptor.c_str()));
    183   for (const DexFile* dex_file : *dex_files) {
    184     const DexFile::ClassDef* dex_class_def = dex_file->FindClassDef(descriptor.c_str(), hash);
    185     if (dex_class_def != nullptr) {
    186       ScopedObjectAccess soa(env);
    187       ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
    188       class_linker->RegisterDexFile(*dex_file);
    189       StackHandleScope<1> hs(soa.Self());
    190       Handle<mirror::ClassLoader> class_loader(
    191           hs.NewHandle(soa.Decode<mirror::ClassLoader*>(javaLoader)));
    192       mirror::Class* result = class_linker->DefineClass(soa.Self(), descriptor.c_str(), hash,
    193                                                         class_loader, *dex_file, *dex_class_def);
    194       if (result != nullptr) {
    195         VLOG(class_linker) << "DexFile_defineClassNative returning " << result;
    196         return soa.AddLocalReference<jclass>(result);
    197       }
    198     }
    199   }
    200   VLOG(class_linker) << "Failed to find dex_class_def";
    201   return nullptr;
    202 }
    203 
    204 // Needed as a compare functor for sets of const char
    205 struct CharPointerComparator {
    206   bool operator()(const char *str1, const char *str2) const {
    207     return strcmp(str1, str2) < 0;
    208   }
    209 };
    210 
    211 // Note: this can be an expensive call, as we sort out duplicates in MultiDex files.
    212 static jobjectArray DexFile_getClassNameList(JNIEnv* env, jclass, jlong cookie) {
    213   jobjectArray result = nullptr;
    214   std::vector<const DexFile*>* dex_files = toDexFiles(cookie, env);
    215 
    216   if (dex_files != nullptr) {
    217     // Push all class descriptors into a set. Use set instead of unordered_set as we want to
    218     // retrieve all in the end.
    219     std::set<const char*, CharPointerComparator> descriptors;
    220     for (const DexFile* dex_file : *dex_files) {
    221       for (size_t i = 0; i < dex_file->NumClassDefs(); ++i) {
    222         const DexFile::ClassDef& class_def = dex_file->GetClassDef(i);
    223         const char* descriptor = dex_file->GetClassDescriptor(class_def);
    224         descriptors.insert(descriptor);
    225       }
    226     }
    227 
    228     // Now create output array and copy the set into it.
    229     result = env->NewObjectArray(descriptors.size(), WellKnownClasses::java_lang_String, nullptr);
    230     if (result != nullptr) {
    231       auto it = descriptors.begin();
    232       auto it_end = descriptors.end();
    233       jsize i = 0;
    234       for (; it != it_end; it++, ++i) {
    235         std::string descriptor(DescriptorToDot(*it));
    236         ScopedLocalRef<jstring> jdescriptor(env, env->NewStringUTF(descriptor.c_str()));
    237         if (jdescriptor.get() == nullptr) {
    238           return nullptr;
    239         }
    240         env->SetObjectArrayElement(result, i, jdescriptor.get());
    241       }
    242     }
    243   }
    244   return result;
    245 }
    246 
    247 static void CopyProfileFile(const char* oldfile, const char* newfile) {
    248   ScopedFd src(open(oldfile, O_RDONLY));
    249   if (src.get() == -1) {
    250     PLOG(ERROR) << "Failed to open profile file " << oldfile
    251       << ". My uid:gid is " << getuid() << ":" << getgid();
    252     return;
    253   }
    254 
    255   struct stat stat_src;
    256   if (fstat(src.get(), &stat_src) == -1) {
    257     PLOG(ERROR) << "Failed to get stats for profile file  " << oldfile
    258       << ". My uid:gid is " << getuid() << ":" << getgid();
    259     return;
    260   }
    261 
    262   // Create the copy with rw------- (only accessible by system)
    263   ScopedFd dst(open(newfile, O_WRONLY|O_CREAT|O_TRUNC, 0600));
    264   if (dst.get()  == -1) {
    265     PLOG(ERROR) << "Failed to create/write prev profile file " << newfile
    266       << ".  My uid:gid is " << getuid() << ":" << getgid();
    267     return;
    268   }
    269 
    270 #ifdef __linux__
    271   if (sendfile(dst.get(), src.get(), nullptr, stat_src.st_size) == -1) {
    272 #else
    273   off_t len;
    274   if (sendfile(dst.get(), src.get(), 0, &len, nullptr, 0) == -1) {
    275 #endif
    276     PLOG(ERROR) << "Failed to copy profile file " << oldfile << " to " << newfile
    277       << ". My uid:gid is " << getuid() << ":" << getgid();
    278   }
    279 }
    280 
    281 // Java: dalvik.system.DexFile.UP_TO_DATE
    282 static const jbyte kUpToDate = 0;
    283 // Java: dalvik.system.DexFile.DEXOPT_NEEDED
    284 static const jbyte kPatchoatNeeded = 1;
    285 // Java: dalvik.system.DexFile.PATCHOAT_NEEDED
    286 static const jbyte kDexoptNeeded = 2;
    287 
    288 template <const bool kVerboseLogging, const bool kReasonLogging>
    289 static jbyte IsDexOptNeededForFile(const std::string& oat_filename, const char* filename,
    290                                    InstructionSet target_instruction_set,
    291                                    bool* oat_is_pic) {
    292   std::string error_msg;
    293   std::unique_ptr<const OatFile> oat_file(OatFile::Open(oat_filename, oat_filename, nullptr,
    294                                                         nullptr,
    295                                                         false, &error_msg));
    296   if (oat_file.get() == nullptr) {
    297     // Note that even though this is kDexoptNeeded, we use
    298     // kVerboseLogging instead of the usual kReasonLogging since it is
    299     // the common case on first boot and very spammy.
    300     if (kVerboseLogging) {
    301       LOG(INFO) << "DexFile_isDexOptNeeded failed to open oat file '" << oat_filename
    302           << "' for file location '" << filename << "': " << error_msg;
    303     }
    304     error_msg.clear();
    305     return kDexoptNeeded;
    306   }
    307 
    308   // Pass-up the information about if this is PIC.
    309   // TODO: Refactor this function to be less complicated.
    310   *oat_is_pic = oat_file->IsPic();
    311 
    312   bool should_relocate_if_possible = Runtime::Current()->ShouldRelocate();
    313   uint32_t location_checksum = 0;
    314   const art::OatFile::OatDexFile* oat_dex_file = oat_file->GetOatDexFile(filename, nullptr,
    315                                                                           kReasonLogging);
    316   if (oat_dex_file != nullptr) {
    317     // If its not possible to read the classes.dex assume up-to-date as we won't be able to
    318     // compile it anyway.
    319     if (!DexFile::GetChecksum(filename, &location_checksum, &error_msg)) {
    320       if (kVerboseLogging) {
    321         LOG(INFO) << "DexFile_isDexOptNeeded found precompiled stripped file: "
    322             << filename << " for " << oat_filename << ": " << error_msg;
    323       }
    324       if (ClassLinker::VerifyOatChecksums(oat_file.get(), target_instruction_set, &error_msg)) {
    325         if (kVerboseLogging) {
    326           LOG(INFO) << "DexFile_isDexOptNeeded file " << oat_filename
    327                     << " is up-to-date for " << filename;
    328         }
    329         return kUpToDate;
    330       } else if (should_relocate_if_possible &&
    331                   ClassLinker::VerifyOatImageChecksum(oat_file.get(), target_instruction_set)) {
    332         if (kReasonLogging) {
    333           LOG(INFO) << "DexFile_isDexOptNeeded file " << oat_filename
    334                     << " needs to be relocated for " << filename;
    335         }
    336         return kPatchoatNeeded;
    337       } else {
    338         if (kReasonLogging) {
    339           LOG(INFO) << "DexFile_isDexOptNeeded file " << oat_filename
    340                     << " is out of date for " << filename;
    341         }
    342         return kDexoptNeeded;
    343       }
    344       // If we get here the file is out of date and we should use the system one to relocate.
    345     } else {
    346       if (ClassLinker::VerifyOatAndDexFileChecksums(oat_file.get(), filename, location_checksum,
    347                                                     target_instruction_set, &error_msg)) {
    348         if (kVerboseLogging) {
    349           LOG(INFO) << "DexFile_isDexOptNeeded file " << oat_filename
    350                     << " is up-to-date for " << filename;
    351         }
    352         return kUpToDate;
    353       } else if (location_checksum == oat_dex_file->GetDexFileLocationChecksum()
    354                   && should_relocate_if_possible
    355                   && ClassLinker::VerifyOatImageChecksum(oat_file.get(), target_instruction_set)) {
    356         if (kReasonLogging) {
    357           LOG(INFO) << "DexFile_isDexOptNeeded file " << oat_filename
    358                     << " needs to be relocated for " << filename;
    359         }
    360         return kPatchoatNeeded;
    361       } else {
    362         if (kReasonLogging) {
    363           LOG(INFO) << "DexFile_isDexOptNeeded file " << oat_filename
    364                     << " is out of date for " << filename;
    365         }
    366         return kDexoptNeeded;
    367       }
    368     }
    369   } else {
    370     if (kReasonLogging) {
    371       LOG(INFO) << "DexFile_isDexOptNeeded file " << oat_filename
    372                 << " does not contain " << filename;
    373     }
    374     return kDexoptNeeded;
    375   }
    376 }
    377 
    378 static jbyte IsDexOptNeededInternal(JNIEnv* env, const char* filename,
    379     const char* pkgname, const char* instruction_set, const jboolean defer) {
    380   // Spammy logging for kUpToDate
    381   const bool kVerboseLogging = false;
    382   // Logging of reason for returning kDexoptNeeded or kPatchoatNeeded.
    383   const bool kReasonLogging = true;
    384 
    385   if ((filename == nullptr) || !OS::FileExists(filename)) {
    386     LOG(ERROR) << "DexFile_isDexOptNeeded file '" << filename << "' does not exist";
    387     ScopedLocalRef<jclass> fnfe(env, env->FindClass("java/io/FileNotFoundException"));
    388     const char* message = (filename == nullptr) ? "<empty file name>" : filename;
    389     env->ThrowNew(fnfe.get(), message);
    390     return kUpToDate;
    391   }
    392 
    393   // Always treat elements of the bootclasspath as up-to-date.  The
    394   // fact that code is running at all means that this should be true.
    395   Runtime* runtime = Runtime::Current();
    396   ClassLinker* class_linker = runtime->GetClassLinker();
    397   // TODO: We're assuming that the 64 and 32 bit runtimes have identical
    398   // class paths. isDexOptNeeded will not necessarily be called on a runtime
    399   // that has the same instruction set as the file being dexopted.
    400   const std::vector<const DexFile*>& boot_class_path = class_linker->GetBootClassPath();
    401   for (size_t i = 0; i < boot_class_path.size(); i++) {
    402     if (boot_class_path[i]->GetLocation() == filename) {
    403       if (kVerboseLogging) {
    404         LOG(INFO) << "DexFile_isDexOptNeeded ignoring boot class path file: " << filename;
    405       }
    406       return kUpToDate;
    407     }
    408   }
    409 
    410   bool force_system_only = false;
    411   bool require_system_version = false;
    412 
    413   // Check the profile file.  We need to rerun dex2oat if the profile has changed significantly
    414   // since the last time, or it's new.
    415   // If the 'defer' argument is true then this will be retried later.  In this case we
    416   // need to make sure that the profile file copy is not made so that we will get the
    417   // same result second time.
    418   std::string profile_file;
    419   std::string prev_profile_file;
    420   bool should_copy_profile = false;
    421   if (Runtime::Current()->GetProfilerOptions().IsEnabled() && (pkgname != nullptr)) {
    422     profile_file = GetDalvikCacheOrDie("profiles", false /* create_if_absent */)
    423         + std::string("/") + pkgname;
    424     prev_profile_file = profile_file + std::string("@old");
    425 
    426     struct stat profstat, prevstat;
    427     int e1 = stat(profile_file.c_str(), &profstat);
    428     int e1_errno = errno;
    429     int e2 = stat(prev_profile_file.c_str(), &prevstat);
    430     int e2_errno = errno;
    431     if (e1 < 0) {
    432       if (e1_errno != EACCES) {
    433         // No profile file, need to run dex2oat, unless we find a file in system
    434         if (kReasonLogging) {
    435           LOG(INFO) << "DexFile_isDexOptNeededInternal profile file " << profile_file << " doesn't exist. "
    436                     << "Will check odex to see if we can find a working version.";
    437         }
    438         // Force it to only accept system files/files with versions in system.
    439         require_system_version = true;
    440       } else {
    441         LOG(INFO) << "DexFile_isDexOptNeededInternal recieved EACCES trying to stat profile file "
    442                   << profile_file;
    443       }
    444     } else if (e2 == 0) {
    445       // There is a previous profile file.  Check if the profile has changed significantly.
    446       // A change in profile is considered significant if X% (change_thr property) of the top K%
    447       // (compile_thr property) samples has changed.
    448       double top_k_threshold = Runtime::Current()->GetProfilerOptions().GetTopKThreshold();
    449       double change_threshold = Runtime::Current()->GetProfilerOptions().GetTopKChangeThreshold();
    450       double change_percent = 0.0;
    451       ProfileFile new_profile, old_profile;
    452       bool new_ok = new_profile.LoadFile(profile_file);
    453       bool old_ok = old_profile.LoadFile(prev_profile_file);
    454       if (!new_ok || !old_ok) {
    455         if (kVerboseLogging) {
    456           LOG(INFO) << "DexFile_isDexOptNeededInternal Ignoring invalid profiles: "
    457                     << (new_ok ?  "" : profile_file) << " " << (old_ok ? "" : prev_profile_file);
    458         }
    459       } else {
    460         std::set<std::string> new_top_k, old_top_k;
    461         new_profile.GetTopKSamples(new_top_k, top_k_threshold);
    462         old_profile.GetTopKSamples(old_top_k, top_k_threshold);
    463         if (new_top_k.empty()) {
    464           if (kVerboseLogging) {
    465             LOG(INFO) << "DexFile_isDexOptNeededInternal empty profile: " << profile_file;
    466           }
    467           // If the new topK is empty we shouldn't optimize so we leave the change_percent at 0.0.
    468         } else {
    469           std::set<std::string> diff;
    470           std::set_difference(new_top_k.begin(), new_top_k.end(), old_top_k.begin(), old_top_k.end(),
    471             std::inserter(diff, diff.end()));
    472           // TODO: consider using the usedPercentage instead of the plain diff count.
    473           change_percent = 100.0 * static_cast<double>(diff.size()) / static_cast<double>(new_top_k.size());
    474           if (kVerboseLogging) {
    475             std::set<std::string>::iterator end = diff.end();
    476             for (std::set<std::string>::iterator it = diff.begin(); it != end; it++) {
    477               LOG(INFO) << "DexFile_isDexOptNeededInternal new in topK: " << *it;
    478             }
    479           }
    480         }
    481       }
    482 
    483       if (change_percent > change_threshold) {
    484         if (kReasonLogging) {
    485           LOG(INFO) << "DexFile_isDexOptNeededInternal size of new profile file " << profile_file <<
    486           " is significantly different from old profile file " << prev_profile_file << " (top "
    487           << top_k_threshold << "% samples changed in proportion of " << change_percent << "%)";
    488         }
    489         should_copy_profile = !defer;
    490         // Force us to only accept system files.
    491         force_system_only = true;
    492       }
    493     } else if (e2_errno == ENOENT) {
    494       // Previous profile does not exist.  Make a copy of the current one.
    495       if (kVerboseLogging) {
    496         LOG(INFO) << "DexFile_isDexOptNeededInternal previous profile doesn't exist: " << prev_profile_file;
    497       }
    498       should_copy_profile = !defer;
    499     } else {
    500       PLOG(INFO) << "Unable to stat previous profile file " << prev_profile_file;
    501     }
    502   }
    503 
    504   const InstructionSet target_instruction_set = GetInstructionSetFromString(instruction_set);
    505   if (target_instruction_set == kNone) {
    506     ScopedLocalRef<jclass> iae(env, env->FindClass("java/lang/IllegalArgumentException"));
    507     std::string message(StringPrintf("Instruction set %s is invalid.", instruction_set));
    508     env->ThrowNew(iae.get(), message.c_str());
    509     return 0;
    510   }
    511 
    512   // Get the filename for odex file next to the dex file.
    513   std::string odex_filename(DexFilenameToOdexFilename(filename, target_instruction_set));
    514   // Get the filename for the dalvik-cache file
    515   std::string cache_dir;
    516   bool have_android_data = false;
    517   bool dalvik_cache_exists = false;
    518   bool is_global_cache = false;
    519   GetDalvikCache(instruction_set, false, &cache_dir, &have_android_data, &dalvik_cache_exists,
    520                  &is_global_cache);
    521   std::string cache_filename;  // was cache_location
    522   bool have_cache_filename = false;
    523   if (dalvik_cache_exists) {
    524     std::string error_msg;
    525     have_cache_filename = GetDalvikCacheFilename(filename, cache_dir.c_str(), &cache_filename,
    526                                                  &error_msg);
    527     if (!have_cache_filename && kVerboseLogging) {
    528       LOG(INFO) << "DexFile_isDexOptNeededInternal failed to find cache file for dex file " << filename
    529                 << ": " << error_msg;
    530     }
    531   }
    532 
    533   bool should_relocate_if_possible = Runtime::Current()->ShouldRelocate();
    534 
    535   jbyte dalvik_cache_decision = -1;
    536   // Lets try the cache first (since we want to load from there since thats where the relocated
    537   // versions will be).
    538   if (have_cache_filename && !force_system_only) {
    539     bool oat_is_pic;
    540     // We can use the dalvik-cache if we find a good file.
    541     dalvik_cache_decision =
    542         IsDexOptNeededForFile<kVerboseLogging, kReasonLogging>(cache_filename, filename,
    543                                                                target_instruction_set, &oat_is_pic);
    544 
    545     // Apps that are compiled with --compile-pic never need to be patchoat-d
    546     if (oat_is_pic && dalvik_cache_decision == kPatchoatNeeded) {
    547       dalvik_cache_decision = kUpToDate;
    548     }
    549     // We will only return DexOptNeeded if both the cache and system return it.
    550     if (dalvik_cache_decision != kDexoptNeeded && !require_system_version) {
    551       CHECK(!(dalvik_cache_decision == kPatchoatNeeded && !should_relocate_if_possible))
    552           << "May not return PatchoatNeeded when patching is disabled.";
    553       return dalvik_cache_decision;
    554     }
    555     // We couldn't find one thats easy. We should now try the system.
    556   }
    557 
    558   bool oat_is_pic;
    559   jbyte system_decision =
    560       IsDexOptNeededForFile<kVerboseLogging, kReasonLogging>(odex_filename, filename,
    561                                                              target_instruction_set, &oat_is_pic);
    562   CHECK(!(system_decision == kPatchoatNeeded && !should_relocate_if_possible))
    563       << "May not return PatchoatNeeded when patching is disabled.";
    564 
    565   // Apps that are compiled with --compile-pic never need to be patchoat-d
    566   if (oat_is_pic && system_decision == kPatchoatNeeded) {
    567     system_decision = kUpToDate;
    568   }
    569 
    570   if (require_system_version && system_decision == kPatchoatNeeded
    571                              && dalvik_cache_decision == kUpToDate) {
    572     // We have a version from system relocated to the cache. Return it.
    573     return dalvik_cache_decision;
    574   }
    575 
    576   if (should_copy_profile && system_decision == kDexoptNeeded) {
    577     CopyProfileFile(profile_file.c_str(), prev_profile_file.c_str());
    578   }
    579 
    580   return system_decision;
    581 }
    582 
    583 static jbyte DexFile_isDexOptNeededInternal(JNIEnv* env, jclass, jstring javaFilename,
    584     jstring javaPkgname, jstring javaInstructionSet, jboolean defer) {
    585   ScopedUtfChars filename(env, javaFilename);
    586   if (env->ExceptionCheck()) {
    587     return 0;
    588   }
    589 
    590   NullableScopedUtfChars pkgname(env, javaPkgname);
    591 
    592   ScopedUtfChars instruction_set(env, javaInstructionSet);
    593   if (env->ExceptionCheck()) {
    594     return 0;
    595   }
    596 
    597   return IsDexOptNeededInternal(env, filename.c_str(), pkgname.c_str(),
    598                                 instruction_set.c_str(), defer);
    599 }
    600 
    601 // public API, NULL pkgname
    602 static jboolean DexFile_isDexOptNeeded(JNIEnv* env, jclass, jstring javaFilename) {
    603   const char* instruction_set = GetInstructionSetString(kRuntimeISA);
    604   ScopedUtfChars filename(env, javaFilename);
    605   return kUpToDate != IsDexOptNeededInternal(env, filename.c_str(), nullptr /* pkgname */,
    606                                              instruction_set, false /* defer */);
    607 }
    608 
    609 
    610 static JNINativeMethod gMethods[] = {
    611   NATIVE_METHOD(DexFile, closeDexFile, "(J)V"),
    612   NATIVE_METHOD(DexFile, defineClassNative, "(Ljava/lang/String;Ljava/lang/ClassLoader;J)Ljava/lang/Class;"),
    613   NATIVE_METHOD(DexFile, getClassNameList, "(J)[Ljava/lang/String;"),
    614   NATIVE_METHOD(DexFile, isDexOptNeeded, "(Ljava/lang/String;)Z"),
    615   NATIVE_METHOD(DexFile, isDexOptNeededInternal, "(Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;Z)B"),
    616   NATIVE_METHOD(DexFile, openDexFileNative, "(Ljava/lang/String;Ljava/lang/String;I)J"),
    617 };
    618 
    619 void register_dalvik_system_DexFile(JNIEnv* env) {
    620   REGISTER_NATIVE_METHODS("dalvik/system/DexFile");
    621 }
    622 
    623 }  // namespace art
    624