ART: Native support for multidex

Native support for zip files with multiple classesX.dex.

Works by explicitly looking for those files in ascending order. As
these files have no file system representation for themselves,
introduce synthetic dex locations: the name of the originating file
plus a colon plus the name of the dex file, e.g., test.jar:classes2.dex.

Opening a zip dex file will return all dex files in this way. This
keeps the changes to dex2oat minimal.

To hide multidex/synthetic names from the Java layer, let the handle
of dalvik.system.DexFile refer to a vector of DexFile objects. When
opening a location, test possible synthetic names and add them to the
vector. Thus, the original multidex jar in the classpath will be
associated with all embedded dex files.

Change-Id: I0de107e1369cbc94416c544aca3b17525c9eac8b

1 files changed, 43 insertions, 7 deletions

diff --git a/runtime/dex_file.h b/runtime/dex_file.h
index 8270a2b..04f1cc1 100644
--- a/runtime/dex_file.h
+++ b/runtime/dex_file.h
@@ -63,6 +63,13 @@ class DexFile {
   // The value of an invalid index.
   static const uint16_t kDexNoIndex16 = 0xFFFF;
 
+  // The separator charactor in MultiDex locations.
+  static constexpr char kMultiDexSeparator = ':';
+
+  // A string version of the previous. This is a define so that we can merge string literals in the
+  // preprocessor.
+  #define kMultiDexSeparatorString ":"
+
   // Raw header_item.
   struct Header {
     uint8_t magic_[8];
@@ -352,8 +359,9 @@ class DexFile {
   // Return true if the checksum could be found, false otherwise.
   static bool GetChecksum(const char* filename, uint32_t* checksum, std::string* error_msg);
 
-  // Opens .dex file, guessing the container format based on file extension
-  static const DexFile* Open(const char* filename, const char* location, std::string* error_msg);
+  // Opens .dex files found in the container, guessing the container format based on file extension.
+  static bool Open(const char* filename, const char* location, std::string* error_msg,
+                   std::vector<const DexFile*>* dex_files);
 
   // Opens .dex file, backed by existing memory
   static const DexFile* Open(const uint8_t* base, size_t size,
@@ -363,9 +371,9 @@ class DexFile {
     return OpenMemory(base, size, location, location_checksum, NULL, error_msg);
   }
 
-  // Opens .dex file from the classes.dex in a zip archive
-  static const DexFile* Open(const ZipArchive& zip_archive, const std::string& location,
-                             std::string* error_msg);
+  // Open all classesXXX.dex files from a zip archive.
+  static bool OpenFromZip(const ZipArchive& zip_archive, const std::string& location,
+                          std::string* error_msg, std::vector<const DexFile*>* dex_files);
 
   // Closes a .dex file.
   virtual ~DexFile();
@@ -823,8 +831,24 @@ class DexFile {
   // Opens a .dex file
   static const DexFile* OpenFile(int fd, const char* location, bool verify, std::string* error_msg);
 
-  // Opens a dex file from within a .jar, .zip, or .apk file
-  static const DexFile* OpenZip(int fd, const std::string& location, std::string* error_msg);
+  // Opens dex files from within a .jar, .zip, or .apk file
+  static bool OpenZip(int fd, const std::string& location, std::string* error_msg,
+                      std::vector<const DexFile*>* dex_files);
+
+  enum class ZipOpenErrorCode {  // private
+    kNoError,
+    kEntryNotFound,
+    kExtractToMemoryError,
+    kDexFileError,
+    kMakeReadOnlyError,
+    kVerifyError
+  };
+
+  // Opens .dex file from the entry_name in a zip archive. error_code is undefined when non-nullptr
+  // return.
+  static const DexFile* Open(const ZipArchive& zip_archive, const char* entry_name,
+                             const std::string& location, std::string* error_msg,
+                             ZipOpenErrorCode* error_code);
 
   // Opens a .dex file at the given address backed by a MemMap
   static const DexFile* OpenMemory(const std::string& location,
@@ -855,6 +879,18 @@ class DexFile {
       DexDebugNewPositionCb position_cb, DexDebugNewLocalCb local_cb,
       void* context, const byte* stream, LocalInfo* local_in_reg) const;
 
+  // Check whether a location denotes a multidex dex file. This is a very simple check: returns
+  // whether the string contains the separator character.
+  static bool IsMultiDexLocation(const char* location);
+
+  // Splits a multidex location at the last separator character. The second component is a pointer
+  // to the character after the separator. The first is a copy of the substring up to the separator.
+  //
+  // Note: It's the caller's job to free the first component of the returned pair.
+  // Bug 15313523: gcc/libc++ don't allow a unique_ptr for the first component
+  static std::pair<const char*, const char*> SplitMultiDexLocation(const char* location);
+
+
   // The base address of the memory mapping.
   const byte* const begin_;