| /*- |
| * Copyright (c) 2003-2007 Tim Kientzle |
| * All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in the |
| * documentation and/or other materials provided with the distribution. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS OR |
| * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
| * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
| * IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, INDIRECT, |
| * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
| * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
| * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| */ |
| |
| #include "archive_platform.h" |
| __FBSDID("$FreeBSD: src/lib/libarchive/archive_read_open_filename.c,v 1.21 2008/02/19 06:10:48 kientzle Exp $"); |
| |
| #ifdef HAVE_SYS_STAT_H |
| #include <sys/stat.h> |
| #endif |
| #ifdef HAVE_ERRNO_H |
| #include <errno.h> |
| #endif |
| #ifdef HAVE_FCNTL_H |
| #include <fcntl.h> |
| #endif |
| #ifdef HAVE_STDLIB_H |
| #include <stdlib.h> |
| #endif |
| #ifdef HAVE_STRING_H |
| #include <string.h> |
| #endif |
| #ifdef HAVE_UNISTD_H |
| #include <unistd.h> |
| #endif |
| |
| #include "archive.h" |
| |
| #ifndef O_BINARY |
| #define O_BINARY 0 |
| #endif |
| |
| struct read_file_data { |
| int fd; |
| size_t block_size; |
| void *buffer; |
| mode_t st_mode; /* Mode bits for opened file. */ |
| char can_skip; /* This file supports skipping. */ |
| char filename[1]; /* Must be last! */ |
| }; |
| |
| static int file_close(struct archive *, void *); |
| static int file_open(struct archive *, void *); |
| static ssize_t file_read(struct archive *, void *, const void **buff); |
| #if ARCHIVE_API_VERSION < 2 |
| static ssize_t file_skip(struct archive *, void *, size_t request); |
| #else |
| static off_t file_skip(struct archive *, void *, off_t request); |
| #endif |
| |
| int |
| archive_read_open_file(struct archive *a, const char *filename, |
| size_t block_size) |
| { |
| return (archive_read_open_filename(a, filename, block_size)); |
| } |
| |
| int |
| archive_read_open_filename(struct archive *a, const char *filename, |
| size_t block_size) |
| { |
| struct read_file_data *mine; |
| |
| if (filename == NULL || filename[0] == '\0') { |
| mine = (struct read_file_data *)malloc(sizeof(*mine)); |
| if (mine == NULL) { |
| archive_set_error(a, ENOMEM, "No memory"); |
| return (ARCHIVE_FATAL); |
| } |
| mine->filename[0] = '\0'; |
| } else { |
| mine = (struct read_file_data *)malloc(sizeof(*mine) + strlen(filename)); |
| if (mine == NULL) { |
| archive_set_error(a, ENOMEM, "No memory"); |
| return (ARCHIVE_FATAL); |
| } |
| strcpy(mine->filename, filename); |
| } |
| mine->block_size = block_size; |
| mine->buffer = NULL; |
| mine->fd = -1; |
| /* lseek() almost never works; disable it by default. See below. */ |
| mine->can_skip = 0; |
| return (archive_read_open2(a, mine, file_open, file_read, file_skip, file_close)); |
| } |
| |
| static int |
| file_open(struct archive *a, void *client_data) |
| { |
| struct read_file_data *mine = (struct read_file_data *)client_data; |
| struct stat st; |
| |
| mine->buffer = malloc(mine->block_size); |
| if (mine->buffer == NULL) { |
| archive_set_error(a, ENOMEM, "No memory"); |
| return (ARCHIVE_FATAL); |
| } |
| if (mine->filename[0] != '\0') |
| mine->fd = open(mine->filename, O_RDONLY | O_BINARY); |
| else |
| mine->fd = 0; /* Fake "open" for stdin. */ |
| if (mine->fd < 0) { |
| archive_set_error(a, errno, "Failed to open '%s'", |
| mine->filename); |
| return (ARCHIVE_FATAL); |
| } |
| if (fstat(mine->fd, &st) == 0) { |
| /* If we're reading a file from disk, ensure that we don't |
| overwrite it with an extracted file. */ |
| if (S_ISREG(st.st_mode)) { |
| archive_read_extract_set_skip_file(a, st.st_dev, st.st_ino); |
| /* |
| * Enabling skip here is a performance |
| * optimization for anything that supports |
| * lseek(). On FreeBSD, only regular files |
| * and raw disk devices support lseek() and |
| * there's no portable way to determine if a |
| * device is a raw disk device, so we only |
| * enable this optimization for regular files. |
| */ |
| mine->can_skip = 1; |
| } |
| /* Remember mode so close can decide whether to flush. */ |
| mine->st_mode = st.st_mode; |
| } else { |
| if (mine->filename[0] == '\0') |
| archive_set_error(a, errno, "Can't stat stdin"); |
| else |
| archive_set_error(a, errno, "Can't stat '%s'", |
| mine->filename); |
| return (ARCHIVE_FATAL); |
| } |
| return (0); |
| } |
| |
| static ssize_t |
| file_read(struct archive *a, void *client_data, const void **buff) |
| { |
| struct read_file_data *mine = (struct read_file_data *)client_data; |
| ssize_t bytes_read; |
| |
| *buff = mine->buffer; |
| bytes_read = read(mine->fd, mine->buffer, mine->block_size); |
| if (bytes_read < 0) { |
| if (mine->filename[0] == '\0') |
| archive_set_error(a, errno, "Error reading stdin"); |
| else |
| archive_set_error(a, errno, "Error reading '%s'", |
| mine->filename); |
| } |
| return (bytes_read); |
| } |
| |
| #if ARCHIVE_API_VERSION < 2 |
| static ssize_t |
| file_skip(struct archive *a, void *client_data, size_t request) |
| #else |
| static off_t |
| file_skip(struct archive *a, void *client_data, off_t request) |
| #endif |
| { |
| struct read_file_data *mine = (struct read_file_data *)client_data; |
| off_t old_offset, new_offset; |
| |
| if (!mine->can_skip) /* We can't skip, so ... */ |
| return (0); /* ... skip zero bytes. */ |
| |
| /* Reduce request to the next smallest multiple of block_size */ |
| request = (request / mine->block_size) * mine->block_size; |
| if (request == 0) |
| return (0); |
| |
| /* |
| * Hurray for lazy evaluation: if the first lseek fails, the second |
| * one will not be executed. |
| */ |
| if (((old_offset = lseek(mine->fd, 0, SEEK_CUR)) < 0) || |
| ((new_offset = lseek(mine->fd, request, SEEK_CUR)) < 0)) |
| { |
| /* If skip failed once, it will probably fail again. */ |
| mine->can_skip = 0; |
| |
| if (errno == ESPIPE) |
| { |
| /* |
| * Failure to lseek() can be caused by the file |
| * descriptor pointing to a pipe, socket or FIFO. |
| * Return 0 here, so the compression layer will use |
| * read()s instead to advance the file descriptor. |
| * It's slower of course, but works as well. |
| */ |
| return (0); |
| } |
| /* |
| * There's been an error other than ESPIPE. This is most |
| * likely caused by a programmer error (too large request) |
| * or a corrupted archive file. |
| */ |
| if (mine->filename[0] == '\0') |
| /* |
| * Should never get here, since lseek() on stdin ought |
| * to return an ESPIPE error. |
| */ |
| archive_set_error(a, errno, "Error seeking in stdin"); |
| else |
| archive_set_error(a, errno, "Error seeking in '%s'", |
| mine->filename); |
| return (-1); |
| } |
| return (new_offset - old_offset); |
| } |
| |
| static int |
| file_close(struct archive *a, void *client_data) |
| { |
| struct read_file_data *mine = (struct read_file_data *)client_data; |
| |
| (void)a; /* UNUSED */ |
| |
| /* |
| * Sometimes, we should flush the input before closing. |
| * Regular files: faster to just close without flush. |
| * Devices: must not flush (user might need to |
| * read the "next" item on a non-rewind device). |
| * Pipes and sockets: must flush (otherwise, the |
| * program feeding the pipe or socket may complain). |
| * Here, I flush everything except for regular files and |
| * device nodes. |
| */ |
| if (!S_ISREG(mine->st_mode) |
| && !S_ISCHR(mine->st_mode) |
| && !S_ISBLK(mine->st_mode)) { |
| ssize_t bytesRead; |
| do { |
| bytesRead = read(mine->fd, mine->buffer, |
| mine->block_size); |
| } while (bytesRead > 0); |
| } |
| /* If a named file was opened, then it needs to be closed. */ |
| if (mine->filename[0] != '\0') |
| close(mine->fd); |
| if (mine->buffer != NULL) |
| free(mine->buffer); |
| free(mine); |
| return (ARCHIVE_OK); |
| } |