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 ssize_t file_read(struct archive *, void *, const void **buff); 59 #if ARCHIVE_API_VERSION < 2 60 static ssize_t file_skip(struct archive *, void *, size_t request); 61 #else 62 static off_t file_skip(struct archive *, void *, off_t request); 63 #endif 64 65 int 66 archive_read_open_FILE(struct archive *a, FILE *f) 67 { 68 struct stat st; 69 struct read_FILE_data *mine; 70 size_t block_size = 128 * 1024; 71 void *b; 72 73 mine = (struct read_FILE_data *)malloc(sizeof(*mine)); 74 b = malloc(block_size); 75 if (mine == NULL || b == NULL) { 76 archive_set_error(a, ENOMEM, "No memory"); 77 free(mine); 78 free(b); 79 return (ARCHIVE_FATAL); 80 } 81 mine->block_size = block_size; 82 mine->buffer = b; 83 mine->f = f; 84 /* 85 * If we can't fstat() the file, it may just be that it's not 86 * a file. (FILE * objects can wrap many kinds of I/O 87 * streams, some of which don't support fileno()).) 88 */ 89 if (fstat(fileno(mine->f), &st) == 0 && S_ISREG(st.st_mode)) { 90 archive_read_extract_set_skip_file(a, st.st_dev, st.st_ino); 91 /* Enable the seek optimization only for regular files. */ 92 mine->can_skip = 1; 93 } else 94 mine->can_skip = 0; 95 96 return (archive_read_open2(a, mine, NULL, file_read, 97 file_skip, file_close)); 98 } 99 100 static ssize_t 101 file_read(struct archive *a, void *client_data, const void **buff) 102 { 103 struct read_FILE_data *mine = (struct read_FILE_data *)client_data; 104 ssize_t bytes_read; 105 106 *buff = mine->buffer; 107 bytes_read = fread(mine->buffer, 1, mine->block_size, mine->f); 108 if (bytes_read < 0) { 109 archive_set_error(a, errno, "Error reading file"); 110 } 111 return (bytes_read); 112 } 113 114 #if ARCHIVE_API_VERSION < 2 115 static ssize_t 116 file_skip(struct archive *a, void *client_data, size_t request) 117 #else 118 static off_t 119 file_skip(struct archive *a, void *client_data, off_t request) 120 #endif 121 { 122 struct read_FILE_data *mine = (struct read_FILE_data *)client_data; 123 124 (void)a; /* UNUSED */ 125 126 /* 127 * If we can't skip, return 0 as the amount we did step and 128 * the caller will work around by reading and discarding. 129 */ 130 if (!mine->can_skip) 131 return (0); 132 if (request == 0) 133 return (0); 134 135 #if HAVE_FSEEKO 136 if (fseeko(mine->f, request, SEEK_CUR) != 0) 137 #else 138 if (fseek(mine->f, request, SEEK_CUR) != 0) 139 #endif 140 { 141 mine->can_skip = 0; 142 return (0); 143 } 144 return (request); 145 } 146 147 static int 148 file_close(struct archive *a, void *client_data) 149 { 150 struct read_FILE_data *mine = (struct read_FILE_data *)client_data; 151 152 (void)a; /* UNUSED */ 153 if (mine->buffer != NULL) 154 free(mine->buffer); 155 free(mine); 156 return (ARCHIVE_OK); 157 } 158