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 /* 18 * Utility functions for dealing with optimized dex files. 19 */ 20 21 #include <stdint.h> 22 #include <stdlib.h> 23 #include <unistd.h> 24 #include <fcntl.h> 25 #include <string.h> 26 #include <sys/stat.h> 27 #include <sys/file.h> 28 #include <errno.h> 29 30 #include "OptInvocation.h" 31 #include "DexFile.h" 32 33 static const char* kCacheDirectoryName = "dalvik-cache"; 34 static const char* kClassesDex = "classes.dex"; 35 36 #if defined(__aarch64__) 37 static const char* kInstructionSet = "arm64"; 38 #elif defined(__arm__) 39 static const char* kInstructionSet = "arm"; 40 #elif defined(__i386__) 41 static const char* kInstructionSet = "x86"; 42 #elif defined(__mips__) 43 static const char* kInstructionSet = "mips"; 44 #elif defined(__x86_64__) 45 static const char* kInstructionSet = "x86_64"; 46 #else 47 #error Unsupported instruction set. 48 #endif 49 50 static int dexOptMkdir(const char* path, int mode) 51 { 52 #ifdef _WIN32 53 return mkdir(path); 54 #else 55 return mkdir(path, mode); 56 #endif 57 } 58 59 /* 60 * Given the filename of a .jar or .dex file, construct the DEX file cache 61 * name. 62 * 63 * For a Jar, "subFileName" is the name of the entry (usually "classes.dex"). 64 * For a DEX, it may be NULL. 65 * 66 * Returns a newly-allocated string, or NULL on failure. 67 */ 68 char* dexOptGenerateCacheFileName(const char* fileName, const char* subFileName) 69 { 70 char nameBuf[512]; 71 char absoluteFile[sizeof(nameBuf)]; 72 const size_t kBufLen = sizeof(nameBuf) - 1; 73 const char* dataRoot; 74 char* cp; 75 76 /* 77 * Get the absolute path of the Jar or DEX file. 78 */ 79 absoluteFile[0] = '\0'; 80 if (fileName[0] != '/') { 81 /* 82 * Generate the absolute path. This doesn't do everything it 83 * should, e.g. if filename is "./out/whatever" it doesn't crunch 84 * the leading "./" out, but it'll do. 85 */ 86 if (getcwd(absoluteFile, kBufLen) == NULL) { 87 ALOGE("Can't get CWD while opening jar file"); 88 return NULL; 89 } 90 strncat(absoluteFile, "/", kBufLen - strlen(absoluteFile)); 91 } 92 strncat(absoluteFile, fileName, kBufLen - strlen(absoluteFile)); 93 94 /* 95 * Append the name of the Jar file entry, if any. This is not currently 96 * required, but will be if we start putting more than one DEX file 97 * in a Jar. 98 */ 99 if (subFileName != NULL) { 100 strncat(absoluteFile, "/", kBufLen - strlen(absoluteFile)); 101 strncat(absoluteFile, subFileName, kBufLen - strlen(absoluteFile)); 102 } 103 104 /* Turn the path into a flat filename by replacing 105 * any slashes after the first one with '@' characters. 106 */ 107 cp = absoluteFile + 1; 108 while (*cp != '\0') { 109 if (*cp == '/') { 110 *cp = '@'; 111 } 112 cp++; 113 } 114 115 /* Build the name of the cache directory. 116 */ 117 dataRoot = getenv("ANDROID_DATA"); 118 if (dataRoot == NULL) 119 dataRoot = "/data"; 120 snprintf(nameBuf, kBufLen, "%s/%s", dataRoot, kCacheDirectoryName); 121 if (strcmp(dataRoot, "/data") != 0) { 122 int result = dexOptMkdir(nameBuf, 0700); 123 if (result != 0 && errno != EEXIST) { 124 ALOGE("Failed to create dalvik-cache directory %s: %s", nameBuf, strerror(errno)); 125 return NULL; 126 } 127 } 128 snprintf(nameBuf, kBufLen, "%s/%s/%s", dataRoot, kCacheDirectoryName, kInstructionSet); 129 if (strcmp(dataRoot, "/data") != 0) { 130 int result = dexOptMkdir(nameBuf, 0700); 131 if (result != 0 && errno != EEXIST) { 132 ALOGE("Failed to create dalvik-cache directory %s: %s", nameBuf, strerror(errno)); 133 return NULL; 134 } 135 } 136 137 /* Tack on the file name for the actual cache file path. 138 */ 139 strncat(nameBuf, absoluteFile, kBufLen - strlen(nameBuf)); 140 141 ALOGV("Cache file for '%s' '%s' is '%s'", fileName, subFileName, nameBuf); 142 return strdup(nameBuf); 143 } 144 145 /* 146 * Create a skeletal "opt" header in a new file. Most of the fields are 147 * initialized to garbage, but we fill in "dexOffset" so others can 148 * see how large the header is. 149 * 150 * "fd" must be positioned at the start of the file. On return, it will 151 * be positioned just past the header, and the place where the DEX data 152 * should go. 153 * 154 * Returns 0 on success, errno on failure. 155 */ 156 int dexOptCreateEmptyHeader(int fd) 157 { 158 DexOptHeader optHdr; 159 ssize_t actual; 160 161 assert(lseek(fd, 0, SEEK_CUR) == 0); 162 163 /* 164 * The data is only expected to be readable on the current system, so 165 * we just write the structure. We do need the file offset to be 64-bit 166 * aligned to fulfill a DEX requirement. 167 */ 168 assert((sizeof(optHdr) & 0x07) == 0); 169 memset(&optHdr, 0xff, sizeof(optHdr)); 170 optHdr.dexOffset = sizeof(optHdr); 171 actual = write(fd, &optHdr, sizeof(optHdr)); 172 if (actual != sizeof(optHdr)) { 173 int err = errno ? errno : -1; 174 ALOGE("opt header write failed: %s", strerror(errno)); 175 return errno; 176 } 177 178 return 0; 179 } 180
