diff options
Diffstat (limited to 'Utilities/cmlibarchive/libarchive/archive_read_open_fd.c')
| -rw-r--r-- | Utilities/cmlibarchive/libarchive/archive_read_open_fd.c | 181 |
1 files changed, 181 insertions, 0 deletions
diff --git a/Utilities/cmlibarchive/libarchive/archive_read_open_fd.c b/Utilities/cmlibarchive/libarchive/archive_read_open_fd.c new file mode 100644 index 000000000..d8f657295 --- /dev/null +++ b/Utilities/cmlibarchive/libarchive/archive_read_open_fd.c @@ -0,0 +1,181 @@ +/*- + * 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: head/lib/libarchive/archive_read_open_fd.c 201103 2009-12-28 03:13:49Z kientzle $"); + +#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_IO_H +#include <io.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" + +struct read_fd_data { + int fd; + size_t block_size; + char use_lseek; + void *buffer; +}; + +static int file_close(struct archive *, void *); +static ssize_t file_read(struct archive *, void *, const void **buff); +static int64_t file_skip(struct archive *, void *, int64_t request); + +int +archive_read_open_fd(struct archive *a, int fd, size_t block_size) +{ + struct stat st; + struct read_fd_data *mine; + void *b; + + archive_clear_error(a); + if (fstat(fd, &st) != 0) { + archive_set_error(a, errno, "Can't stat fd %d", fd); + return (ARCHIVE_FATAL); + } + + mine = (struct read_fd_data *)calloc(1, sizeof(*mine)); + b = malloc(block_size); + if (mine == NULL || b == NULL) { + archive_set_error(a, ENOMEM, "No memory"); + free(mine); + free(b); + return (ARCHIVE_FATAL); + } + mine->block_size = block_size; + mine->buffer = b; + mine->fd = fd; + /* + * Skip support 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. + */ + if (S_ISREG(st.st_mode)) { + archive_read_extract_set_skip_file(a, st.st_dev, st.st_ino); + mine->use_lseek = 1; + } +#if defined(__CYGWIN__) || defined(_WIN32) + setmode(mine->fd, O_BINARY); +#endif + + archive_read_set_read_callback(a, file_read); + archive_read_set_skip_callback(a, file_skip); + archive_read_set_close_callback(a, file_close); + archive_read_set_callback_data(a, mine); + return (archive_read_open1(a)); +} + +static ssize_t +file_read(struct archive *a, void *client_data, const void **buff) +{ + struct read_fd_data *mine = (struct read_fd_data *)client_data; + ssize_t bytes_read; + + *buff = mine->buffer; + for (;;) { + bytes_read = read(mine->fd, mine->buffer, mine->block_size); + if (bytes_read < 0) { + if (errno == EINTR) + continue; + archive_set_error(a, errno, "Error reading fd %d", mine->fd); + } + return (bytes_read); + } +} + +static int64_t +file_skip(struct archive *a, void *client_data, int64_t request) +{ + struct read_fd_data *mine = (struct read_fd_data *)client_data; + off_t skip = (off_t)request; + off_t old_offset, new_offset; + int skip_bits = sizeof(skip) * 8 - 1; /* off_t is a signed type. */ + + if (!mine->use_lseek) + return (0); + + /* Reduce a request that would overflow the 'skip' variable. */ + if (sizeof(request) > sizeof(skip)) { + int64_t max_skip = + (((int64_t)1 << (skip_bits - 1)) - 1) * 2 + 1; + if (request > max_skip) + skip = max_skip; + } + + /* Reduce request to the next smallest multiple of block_size */ + request = (request / mine->block_size) * mine->block_size; + if (request == 0) + return (0); + + if (((old_offset = lseek(mine->fd, 0, SEEK_CUR)) >= 0) && + ((new_offset = lseek(mine->fd, skip, SEEK_CUR)) >= 0)) + return (new_offset - old_offset); + + /* If seek failed once, it will probably fail again. */ + mine->use_lseek = 0; + + /* Let libarchive recover with read+discard. */ + if (errno == ESPIPE) + 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. + */ + archive_set_error(a, errno, "Error seeking"); + return (-1); +} + +static int +file_close(struct archive *a, void *client_data) +{ + struct read_fd_data *mine = (struct read_fd_data *)client_data; + + (void)a; /* UNUSED */ + free(mine->buffer); + free(mine); + return (ARCHIVE_OK); +} |