1 /* 2 * Copyright (C) 2006 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 // Zip archive entries. 19 // 20 // The ZipEntry class is tightly meshed with the ZipFile class. 21 // 22 #ifndef __LIBS_ZIPENTRY_H 23 #define __LIBS_ZIPENTRY_H 24 25 #include <utils/Errors.h> 26 27 #include <stdlib.h> 28 #include <stdio.h> 29 30 namespace android { 31 32 class ZipFile; 33 34 /* 35 * ZipEntry objects represent a single entry in a Zip archive. 36 * 37 * You can use one of these to get or set information about an entry, but 38 * there are no functions here for accessing the data itself. (We could 39 * tuck a pointer to the ZipFile in here for convenience, but that raises 40 * the likelihood of using ZipEntry objects after discarding the ZipFile.) 41 * 42 * File information is stored in two places: next to the file data (the Local 43 * File Header, and possibly a Data Descriptor), and at the end of the file 44 * (the Central Directory Entry). The two must be kept in sync. 45 */ 46 class ZipEntry { 47 public: 48 friend class ZipFile; 49 ZipEntry(void)50 ZipEntry(void) 51 : mDeleted(false), mMarked(false) 52 {} ~ZipEntry(void)53 ~ZipEntry(void) {} 54 55 /* 56 * Returns "true" if the data is compressed. 57 */ isCompressed(void)58 bool isCompressed(void) const { 59 return mCDE.mCompressionMethod != kCompressStored; 60 } getCompressionMethod(void)61 int getCompressionMethod(void) const { return mCDE.mCompressionMethod; } 62 63 /* 64 * Return the uncompressed length. 65 */ getUncompressedLen(void)66 off_t getUncompressedLen(void) const { return mCDE.mUncompressedSize; } 67 68 /* 69 * Return the compressed length. For uncompressed data, this returns 70 * the same thing as getUncompresesdLen(). 71 */ getCompressedLen(void)72 off_t getCompressedLen(void) const { return mCDE.mCompressedSize; } 73 74 /* 75 * Return the offset of the local file header. 76 */ getLFHOffset(void)77 off_t getLFHOffset(void) const { return mCDE.mLocalHeaderRelOffset; } 78 79 /* 80 * Return the absolute file offset of the start of the compressed or 81 * uncompressed data. 82 */ getFileOffset(void)83 off_t getFileOffset(void) const { 84 return mCDE.mLocalHeaderRelOffset + 85 LocalFileHeader::kLFHLen + 86 mLFH.mFileNameLength + 87 mLFH.mExtraFieldLength; 88 } 89 90 /* 91 * Return the data CRC. 92 */ getCRC32(void)93 unsigned long getCRC32(void) const { return mCDE.mCRC32; } 94 95 /* 96 * Return file modification time in UNIX seconds-since-epoch. 97 */ 98 time_t getModWhen(void) const; 99 100 /* 101 * Return the archived file name. 102 */ getFileName(void)103 const char* getFileName(void) const { return (const char*) mCDE.mFileName; } 104 105 /* 106 * Application-defined "mark". Can be useful when synchronizing the 107 * contents of an archive with contents on disk. 108 */ getMarked(void)109 bool getMarked(void) const { return mMarked; } setMarked(bool val)110 void setMarked(bool val) { mMarked = val; } 111 112 /* 113 * Some basic functions for raw data manipulation. "LE" means 114 * Little Endian. 115 */ getShortLE(const unsigned char * buf)116 static inline unsigned short getShortLE(const unsigned char* buf) { 117 return buf[0] | (buf[1] << 8); 118 } getLongLE(const unsigned char * buf)119 static inline unsigned long getLongLE(const unsigned char* buf) { 120 return buf[0] | (buf[1] << 8) | (buf[2] << 16) | (buf[3] << 24); 121 } putShortLE(unsigned char * buf,short val)122 static inline void putShortLE(unsigned char* buf, short val) { 123 buf[0] = (unsigned char) val; 124 buf[1] = (unsigned char) (val >> 8); 125 } putLongLE(unsigned char * buf,long val)126 static inline void putLongLE(unsigned char* buf, long val) { 127 buf[0] = (unsigned char) val; 128 buf[1] = (unsigned char) (val >> 8); 129 buf[2] = (unsigned char) (val >> 16); 130 buf[3] = (unsigned char) (val >> 24); 131 } 132 133 /* defined for Zip archives */ 134 enum { 135 kCompressStored = 0, // no compression 136 // shrunk = 1, 137 // reduced 1 = 2, 138 // reduced 2 = 3, 139 // reduced 3 = 4, 140 // reduced 4 = 5, 141 // imploded = 6, 142 // tokenized = 7, 143 kCompressDeflated = 8, // standard deflate 144 // Deflate64 = 9, 145 // lib imploded = 10, 146 // reserved = 11, 147 // bzip2 = 12, 148 }; 149 150 /* 151 * Deletion flag. If set, the entry will be removed on the next 152 * call to "flush". 153 */ getDeleted(void)154 bool getDeleted(void) const { return mDeleted; } 155 156 protected: 157 /* 158 * Initialize the structure from the file, which is pointing at 159 * our Central Directory entry. 160 */ 161 status_t initFromCDE(FILE* fp); 162 163 /* 164 * Initialize the structure for a new file. We need the filename 165 * and comment so that we can properly size the LFH area. The 166 * filename is mandatory, the comment is optional. 167 */ 168 void initNew(const char* fileName, const char* comment); 169 170 /* 171 * Initialize the structure with the contents of a ZipEntry from 172 * another file. 173 */ 174 status_t initFromExternal(const ZipFile* pZipFile, const ZipEntry* pEntry); 175 176 /* 177 * Add some pad bytes to the LFH. We do this by adding or resizing 178 * the "extra" field. 179 */ 180 status_t addPadding(int padding); 181 182 /* 183 * Set information about the data for this entry. 184 */ 185 void setDataInfo(long uncompLen, long compLen, unsigned long crc32, 186 int compressionMethod); 187 188 /* 189 * Set the modification date. 190 */ 191 void setModWhen(time_t when); 192 193 /* 194 * Set the offset of the local file header, relative to the start of 195 * the current file. 196 */ setLFHOffset(off_t offset)197 void setLFHOffset(off_t offset) { 198 mCDE.mLocalHeaderRelOffset = (long) offset; 199 } 200 201 /* mark for deletion; used by ZipFile::remove() */ setDeleted(void)202 void setDeleted(void) { mDeleted = true; } 203 204 private: 205 /* these are private and not defined */ 206 ZipEntry(const ZipEntry& src); 207 ZipEntry& operator=(const ZipEntry& src); 208 209 /* returns "true" if the CDE and the LFH agree */ 210 bool compareHeaders(void) const; 211 void copyCDEtoLFH(void); 212 213 bool mDeleted; // set if entry is pending deletion 214 bool mMarked; // app-defined marker 215 216 /* 217 * Every entry in the Zip archive starts off with one of these. 218 */ 219 class LocalFileHeader { 220 public: LocalFileHeader(void)221 LocalFileHeader(void) : 222 mVersionToExtract(0), 223 mGPBitFlag(0), 224 mCompressionMethod(0), 225 mLastModFileTime(0), 226 mLastModFileDate(0), 227 mCRC32(0), 228 mCompressedSize(0), 229 mUncompressedSize(0), 230 mFileNameLength(0), 231 mExtraFieldLength(0), 232 mFileName(NULL), 233 mExtraField(NULL) 234 {} ~LocalFileHeader(void)235 virtual ~LocalFileHeader(void) { 236 delete[] mFileName; 237 delete[] mExtraField; 238 } 239 240 status_t read(FILE* fp); 241 status_t write(FILE* fp); 242 243 // unsigned long mSignature; 244 unsigned short mVersionToExtract; 245 unsigned short mGPBitFlag; 246 unsigned short mCompressionMethod; 247 unsigned short mLastModFileTime; 248 unsigned short mLastModFileDate; 249 unsigned long mCRC32; 250 unsigned long mCompressedSize; 251 unsigned long mUncompressedSize; 252 unsigned short mFileNameLength; 253 unsigned short mExtraFieldLength; 254 unsigned char* mFileName; 255 unsigned char* mExtraField; 256 257 enum { 258 kSignature = 0x04034b50, 259 kLFHLen = 30, // LocalFileHdr len, excl. var fields 260 }; 261 262 void dump(void) const; 263 }; 264 265 /* 266 * Every entry in the Zip archive has one of these in the "central 267 * directory" at the end of the file. 268 */ 269 class CentralDirEntry { 270 public: CentralDirEntry(void)271 CentralDirEntry(void) : 272 mVersionMadeBy(0), 273 mVersionToExtract(0), 274 mGPBitFlag(0), 275 mCompressionMethod(0), 276 mLastModFileTime(0), 277 mLastModFileDate(0), 278 mCRC32(0), 279 mCompressedSize(0), 280 mUncompressedSize(0), 281 mFileNameLength(0), 282 mExtraFieldLength(0), 283 mFileCommentLength(0), 284 mDiskNumberStart(0), 285 mInternalAttrs(0), 286 mExternalAttrs(0), 287 mLocalHeaderRelOffset(0), 288 mFileName(NULL), 289 mExtraField(NULL), 290 mFileComment(NULL) 291 {} ~CentralDirEntry(void)292 virtual ~CentralDirEntry(void) { 293 delete[] mFileName; 294 delete[] mExtraField; 295 delete[] mFileComment; 296 } 297 298 status_t read(FILE* fp); 299 status_t write(FILE* fp); 300 301 CentralDirEntry& operator=(const CentralDirEntry& src); 302 303 // unsigned long mSignature; 304 unsigned short mVersionMadeBy; 305 unsigned short mVersionToExtract; 306 unsigned short mGPBitFlag; 307 unsigned short mCompressionMethod; 308 unsigned short mLastModFileTime; 309 unsigned short mLastModFileDate; 310 unsigned long mCRC32; 311 unsigned long mCompressedSize; 312 unsigned long mUncompressedSize; 313 unsigned short mFileNameLength; 314 unsigned short mExtraFieldLength; 315 unsigned short mFileCommentLength; 316 unsigned short mDiskNumberStart; 317 unsigned short mInternalAttrs; 318 unsigned long mExternalAttrs; 319 unsigned long mLocalHeaderRelOffset; 320 unsigned char* mFileName; 321 unsigned char* mExtraField; 322 unsigned char* mFileComment; 323 324 void dump(void) const; 325 326 enum { 327 kSignature = 0x02014b50, 328 kCDELen = 46, // CentralDirEnt len, excl. var fields 329 }; 330 }; 331 332 enum { 333 //kDataDescriptorSignature = 0x08074b50, // currently unused 334 kDataDescriptorLen = 16, // four 32-bit fields 335 336 kDefaultVersion = 20, // need deflate, nothing much else 337 kDefaultMadeBy = 0x0317, // 03=UNIX, 17=spec v2.3 338 kUsesDataDescr = 0x0008, // GPBitFlag bit 3 339 }; 340 341 LocalFileHeader mLFH; 342 CentralDirEntry mCDE; 343 }; 344 345 }; // namespace android 346 347 #endif // __LIBS_ZIPENTRY_H 348