1 /* 2 * Copyright (C) 2007 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 // Miscellaneous zip/gzip utility functions. 19 // 20 #ifndef __LIBS_ZIPUTILS_H 21 #define __LIBS_ZIPUTILS_H 22 23 #include <stdio.h> 24 #include <time.h> 25 26 namespace android { 27 28 /* 29 * Container class for utility functions, primarily for namespace reasons. 30 */ 31 class ZipUtils { 32 public: 33 /* 34 * General utility function for uncompressing "deflate" data from a file 35 * to a buffer. 36 */ 37 static bool inflateToBuffer(FILE* fp, void* buf, long uncompressedLen, 38 long compressedLen); 39 static bool inflateToBuffer(int fd, void* buf, long uncompressedLen, 40 long compressedLen); 41 static bool inflateToBuffer(void *in, void* buf, long uncompressedLen, 42 long compressedLen); 43 44 /* 45 * Someday we might want to make this generic and handle bzip2 ".bz2" 46 * files too. 47 * 48 * We could declare gzip to be a sub-class of zip that has exactly 49 * one always-compressed entry, but we currently want to treat Zip 50 * and gzip as distinct, so there's no value. 51 * 52 * The zlib library has some gzip utilities, but it has no interface 53 * for extracting the uncompressed length of the file (you do *not* 54 * want to gzseek to the end). 55 * 56 * Pass in a seeked file pointer for the gzip file. If this is a gzip 57 * file, we set our return values appropriately and return "true" with 58 * the file seeked to the start of the compressed data. 59 */ 60 static bool examineGzip(FILE* fp, int* pCompressionMethod, 61 long* pUncompressedLen, long* pCompressedLen, unsigned long* pCRC32); 62 63 /* 64 * Utility function to convert ZIP's time format to a timespec struct. 65 */ 66 static inline void zipTimeToTimespec(long when, struct tm* timespec) { 67 const long date = when >> 16; 68 timespec->tm_year = ((date >> 9) & 0x7F) + 80; // Zip is years since 1980 69 timespec->tm_mon = (date >> 5) & 0x0F; 70 timespec->tm_mday = date & 0x1F; 71 72 timespec->tm_hour = (when >> 11) & 0x1F; 73 timespec->tm_min = (when >> 5) & 0x3F; 74 timespec->tm_sec = (when & 0x1F) << 1; 75 } 76 private: 77 ZipUtils() {} 78 ~ZipUtils() {} 79 }; 80 81 }; // namespace android 82 83 #endif /*__LIBS_ZIPUTILS_H*/ 84
