1 /*- 2 * Copyright (c) 2003-2007 Tim Kientzle 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS OR 15 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 16 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 17 * IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, INDIRECT, 18 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 19 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 20 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 21 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 23 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 24 */ 25 26 #include "archive_platform.h" 27 __FBSDID("$FreeBSD: src/lib/libarchive/archive_read_open_file.c,v 1.20 2007/06/26 03:06:48 kientzle Exp $"); 28 29 #ifdef HAVE_SYS_STAT_H 30 #include <sys/stat.h> 31 #endif 32 #ifdef HAVE_ERRNO_H 33 #include <errno.h> 34 #endif 35 #ifdef HAVE_FCNTL_H 36 #include <fcntl.h> 37 #endif 38 #ifdef HAVE_STDLIB_H 39 #include <stdlib.h> 40 #endif 41 #ifdef HAVE_STRING_H 42 #include <string.h> 43 #endif 44 #ifdef HAVE_UNISTD_H 45 #include <unistd.h> 46 #endif 47 48 #include "archive.h" 49 50 struct read_FILE_data { 51 FILE *f; 52 size_t block_size; 53 void *buffer; 54 char can_skip; 55 }; 56 57 static int file_close(struct archive *, void *); 58 static int file_open(struct archive *, void *); 59 static ssize_t file_read(struct archive *, void *, const void **buff); 60 #if ARCHIVE_API_VERSION < 2 61 static ssize_t file_skip(struct archive *, void *, size_t request); 62 #else 63 static off_t file_skip(struct archive *, void *, off_t request); 64 #endif 65 66 int 67 archive_read_open_FILE(struct archive *a, FILE *f) 68 { 69 struct read_FILE_data *mine; 70 71 mine = (struct read_FILE_data *)malloc(sizeof(*mine)); 72 if (mine == NULL) { 73 archive_set_error(a, ENOMEM, "No memory"); 74 return (ARCHIVE_FATAL); 75 } 76 mine->block_size = 128 * 1024; 77 mine->buffer = malloc(mine->block_size); 78 if (mine->buffer == NULL) { 79 archive_set_error(a, ENOMEM, "No memory"); 80 free(mine); 81 return (ARCHIVE_FATAL); 82 } 83 mine->f = f; 84 /* Suppress skip by default. See below. */ 85 mine->can_skip = 0; 86 return (archive_read_open2(a, mine, file_open, file_read, 87 file_skip, file_close)); 88 } 89 90 static int 91 file_open(struct archive *a, void *client_data) 92 { 93 struct read_FILE_data *mine = (struct read_FILE_data *)client_data; 94 struct stat st; 95 96 /* 97 * If we can't fstat() the file, it may just be that 98 * it's not a file. (FILE * objects can wrap many kinds 99 * of I/O streams.) 100 */ 101 if (fstat(fileno(mine->f), &st) == 0 && S_ISREG(st.st_mode)) { 102 archive_read_extract_set_skip_file(a, st.st_dev, st.st_ino); 103 /* Enable the seek optimization for regular files. */ 104 mine->can_skip = 1; 105 } 106 107 return (ARCHIVE_OK); 108 } 109 110 static ssize_t 111 file_read(struct archive *a, void *client_data, const void **buff) 112 { 113 struct read_FILE_data *mine = (struct read_FILE_data *)client_data; 114 ssize_t bytes_read; 115 116 *buff = mine->buffer; 117 bytes_read = fread(mine->buffer, 1, mine->block_size, mine->f); 118 if (bytes_read < 0) { 119 archive_set_error(a, errno, "Error reading file"); 120 } 121 return (bytes_read); 122 } 123 124 #if ARCHIVE_API_VERSION < 2 125 static ssize_t 126 file_skip(struct archive *a, void *client_data, size_t request) 127 #else 128 static off_t 129 file_skip(struct archive *a, void *client_data, off_t request) 130 #endif 131 { 132 struct read_FILE_data *mine = (struct read_FILE_data *)client_data; 133 134 (void)a; /* UNUSED */ 135 136 /* 137 * If we can't skip, return 0 as the amount we did step and 138 * the caller will work around by reading and discarding. 139 */ 140 if (!mine->can_skip) 141 return (0); 142 if (request == 0) 143 return (0); 144 145 #if HAVE_FSEEKO 146 if (fseeko(mine->f, request, SEEK_CUR) != 0) 147 #else 148 if (fseek(mine->f, request, SEEK_CUR) != 0) 149 #endif 150 { 151 mine->can_skip = 0; 152 return (0); 153 } 154 return (request); 155 } 156 157 static int 158 file_close(struct archive *a, void *client_data) 159 { 160 struct read_FILE_data *mine = (struct read_FILE_data *)client_data; 161 162 (void)a; /* UNUSED */ 163 if (mine->buffer != NULL) 164 free(mine->buffer); 165 free(mine); 166 return (ARCHIVE_OK); 167 } 168