file_id.cc revision fd98b2af3773437487af0df22c428f3db630949a
1// Copyright (c) 2006, Google Inc. 2// All rights reserved. 3// 4// Redistribution and use in source and binary forms, with or without 5// modification, are permitted provided that the following conditions are 6// met: 7// 8// * Redistributions of source code must retain the above copyright 9// notice, this list of conditions and the following disclaimer. 10// * Redistributions in binary form must reproduce the above 11// copyright notice, this list of conditions and the following disclaimer 12// in the documentation and/or other materials provided with the 13// distribution. 14// * Neither the name of Google Inc. nor the names of its 15// contributors may be used to endorse or promote products derived from 16// this software without specific prior written permission. 17// 18// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 19// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 20// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 21// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 22// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 23// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 24// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 25// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 26// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 27// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 28// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 29// 30// file_id.cc: Return a unique identifier for a file 31// 32// See file_id.h for documentation 33// 34// Author: Dan Waylonis 35 36#include <fcntl.h> 37#include <string.h> 38#include <unistd.h> 39 40#include "common/mac/file_id.h" 41#include "common/mac/macho_id.h" 42 43using MacFileUtilities::MachoID; 44 45namespace google_airbag { 46 47FileID::FileID(const char *path) { 48 strlcpy(path_, path, sizeof(path_)); 49} 50 51bool FileID::FileIdentifier(unsigned char identifier[16]) { 52 int fd = open(path_, O_RDONLY); 53 if (fd == -1) 54 return false; 55 56 MD5_CTX md5; 57 MD5_Init(&md5); 58 59 // Read 4k x 2 bytes at a time. This is faster than just 4k bytes, but 60 // doesn't seem to be an unreasonable size for the stack. 61 unsigned char buffer[4096 * 2]; 62 size_t buffer_size = sizeof(buffer); 63 while ((buffer_size = read(fd, buffer, buffer_size) > 0)) { 64 MD5_Update(&md5, buffer, buffer_size); 65 } 66 67 close(fd); 68 MD5_Final(identifier, &md5); 69 70 return true; 71} 72 73bool FileID::MachoIdentifier(int cpu_type, unsigned char identifier[16]) { 74 MachoID macho(path_); 75 76 if (macho.UUIDCommand(cpu_type, identifier)) 77 return true; 78 79 if (macho.IDCommand(cpu_type, identifier)) 80 return true; 81 82 return macho.MD5(cpu_type, identifier); 83} 84 85// static 86void FileID::ConvertIdentifierToString(const unsigned char identifier[16], 87 char *buffer, int buffer_length) { 88 int buffer_idx = 0; 89 for (int idx = 0; (buffer_idx < buffer_length) && (idx < 16); ++idx) { 90 int hi = (identifier[idx] >> 4) & 0x0F; 91 int lo = (identifier[idx]) & 0x0F; 92 93 if (idx == 4 || idx == 6 || idx == 8 || idx == 10) 94 buffer[buffer_idx++] = '-'; 95 96 buffer[buffer_idx++] = (hi >= 10) ? 'A' + hi - 10 : '0' + hi; 97 buffer[buffer_idx++] = (lo >= 10) ? 'A' + lo - 10 : '0' + lo; 98 } 99 100 // NULL terminate 101 buffer[(buffer_idx < buffer_length) ? buffer_idx : buffer_idx - 1] = 0; 102} 103 104} // namespace google_airbag 105