diff options
Diffstat (limited to 'lib/libarchive/archive_read_open_filename.c')
| -rw-r--r-- | lib/libarchive/archive_read_open_filename.c | 272 |
1 files changed, 272 insertions, 0 deletions
diff --git a/lib/libarchive/archive_read_open_filename.c b/lib/libarchive/archive_read_open_filename.c new file mode 100644 index 0000000..3d6c5dc --- /dev/null +++ b/lib/libarchive/archive_read_open_filename.c @@ -0,0 +1,272 @@ +/*- + * 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("$FreeBSD$"); + +#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" + +#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 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 stat st; + struct read_file_data *mine; + void *b; + int fd; + + archive_clear_error(a); + if (filename == NULL || filename[0] == '\0') { + /* We used to invoke archive_read_open_fd(a,0,block_size) + * here, but that doesn't (and shouldn't) handle the + * end-of-file flush when reading stdout from a pipe. + * Basically, read_open_fd() is intended for folks who + * are willing to handle such details themselves. This + * API is intended to be a little smarter for folks who + * want easy handling of the common case. + */ + filename = ""; /* Normalize NULL to "" */ + fd = 0; +#if defined(__CYGWIN__) || defined(_WIN32) + setmode(0, O_BINARY); +#endif + } else { + fd = open(filename, O_RDONLY | O_BINARY); + if (fd < 0) { + archive_set_error(a, errno, + "Failed to open '%s'", filename); + return (ARCHIVE_FATAL); + } + } + if (fstat(fd, &st) != 0) { + archive_set_error(a, errno, "Can't stat '%s'", filename); + return (ARCHIVE_FATAL); + } + + mine = (struct read_file_data *)calloc(1, + sizeof(*mine) + strlen(filename)); + b = malloc(block_size); + if (mine == NULL || b == NULL) { + archive_set_error(a, ENOMEM, "No memory"); + free(mine); + free(b); + return (ARCHIVE_FATAL); + } + strcpy(mine->filename, filename); + mine->block_size = block_size; + mine->buffer = b; + mine->fd = fd; + /* Remember mode so close can decide whether to flush. */ + mine->st_mode = st.st_mode; + /* 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 + * (and probably many other systems), only regular + * files and raw disk devices support lseek() (on + * other input types, lseek() returns success but + * doesn't actually change the file pointer, which + * just completely screws up the position-tracking + * logic). In addition, I've yet to find a portable + * way to determine if a device is a raw disk device. + * So I don't see a way to do much better than to only + * enable this optimization for regular files. + */ + mine->can_skip = 1; + } + return (archive_read_open2(a, mine, + NULL, file_read, file_skip, file_close)); +} + +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; + for (;;) { + bytes_read = read(mine->fd, mine->buffer, mine->block_size); + if (bytes_read < 0) { + if (errno == EINTR) + continue; + else 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 */ + + /* Only flush and close if open succeeded. */ + if (mine->fd >= 0) { + /* + * 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); + } + free(mine->buffer); + free(mine); + return (ARCHIVE_OK); +} |
