freebsd-dev/lib/libarchive/archive_write_set_compression_program.c
Tim Kientzle 936d273c3a A number of minor corrections to the support for external compression
programs:
  * Support platforms that have fork() but not vfork()
  * Don't write(), select(), or poll() against closed file descriptors
2008-06-15 10:45:57 +00:00

350 lines
9.1 KiB
C

/*-
* Copyright (c) 2007 Joerg Sonnenberger
* 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("$FreeBSD$");
/* This capability is only available on POSIX systems. */
#if !defined(HAVE_PIPE) || !defined(HAVE_FCNTL) || \
!(defined(HAVE_FORK) || defined(HAVE_VFORK))
#include "archive.h"
/*
* On non-Posix systems, allow the program to build, but choke if
* this function is actually invoked.
*/
int
archive_write_set_compression_program(struct archive *_a, const char *cmd)
{
archive_set_error(_a, -1,
"External compression programs not supported on this platform");
return (ARCHIVE_FATAL);
}
#else
#ifdef HAVE_SYS_WAIT_H
# include <sys/wait.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
#include "archive.h"
#include "archive_private.h"
#include "archive_write_private.h"
#include "filter_fork.h"
struct private_data {
char *description;
pid_t child;
int child_stdin, child_stdout;
char *child_buf;
size_t child_buf_len, child_buf_avail;
};
static int archive_compressor_program_finish(struct archive_write *);
static int archive_compressor_program_init(struct archive_write *);
static int archive_compressor_program_write(struct archive_write *,
const void *, size_t);
/*
* Allocate, initialize and return a archive object.
*/
int
archive_write_set_compression_program(struct archive *_a, const char *cmd)
{
struct archive_write *a = (struct archive_write *)_a;
__archive_check_magic(&a->archive, ARCHIVE_WRITE_MAGIC,
ARCHIVE_STATE_NEW, "archive_write_set_compression_program");
a->compressor.init = &archive_compressor_program_init;
a->compressor.config = strdup(cmd);
return (ARCHIVE_OK);
}
/*
* Setup callback.
*/
static int
archive_compressor_program_init(struct archive_write *a)
{
int ret;
struct private_data *state;
static const char *prefix = "Program: ";
char *cmd = a->compressor.config;
if (a->client_opener != NULL) {
ret = (a->client_opener)(&a->archive, a->client_data);
if (ret != ARCHIVE_OK)
return (ret);
}
state = (struct private_data *)malloc(sizeof(*state));
if (state == NULL) {
archive_set_error(&a->archive, ENOMEM,
"Can't allocate data for compression");
return (ARCHIVE_FATAL);
}
memset(state, 0, sizeof(*state));
a->archive.compression_code = ARCHIVE_COMPRESSION_PROGRAM;
state->description = (char *)malloc(strlen(prefix) + strlen(cmd) + 1);
strcpy(state->description, prefix);
strcat(state->description, cmd);
a->archive.compression_name = state->description;
state->child_buf_len = a->bytes_per_block;
state->child_buf_avail = 0;
state->child_buf = malloc(state->child_buf_len);
if (state->child_buf == NULL) {
archive_set_error(&a->archive, ENOMEM,
"Can't allocate data for compression buffer");
free(state);
return (ARCHIVE_FATAL);
}
if ((state->child = __archive_create_child(cmd,
&state->child_stdin, &state->child_stdout)) == -1) {
archive_set_error(&a->archive, EINVAL,
"Can't initialise filter");
free(state->child_buf);
free(state);
return (ARCHIVE_FATAL);
}
a->compressor.write = archive_compressor_program_write;
a->compressor.finish = archive_compressor_program_finish;
a->compressor.data = state;
return (0);
}
static ssize_t
child_write(struct archive_write *a, const char *buf, size_t buf_len)
{
struct private_data *state = a->compressor.data;
ssize_t ret;
if (state->child_stdin == -1)
return (-1);
if (buf_len == 0)
return (-1);
restart_write:
do {
ret = write(state->child_stdin, buf, buf_len);
} while (ret == -1 && errno == EINTR);
if (ret > 0)
return (ret);
if (ret == 0) {
close(state->child_stdin);
state->child_stdin = -1;
fcntl(state->child_stdout, F_SETFL, 0);
return (0);
}
if (ret == -1 && errno != EAGAIN)
return (-1);
if (state->child_stdout == -1) {
fcntl(state->child_stdin, F_SETFL, 0);
__archive_check_child(state->child_stdin, state->child_stdout);
goto restart_write;
}
do {
ret = read(state->child_stdout,
state->child_buf + state->child_buf_avail,
state->child_buf_len - state->child_buf_avail);
} while (ret == -1 && errno == EINTR);
if (ret == 0 || (ret == -1 && errno == EPIPE)) {
close(state->child_stdout);
state->child_stdout = -1;
fcntl(state->child_stdin, F_SETFL, 0);
goto restart_write;
}
if (ret == -1 && errno == EAGAIN) {
__archive_check_child(state->child_stdin, state->child_stdout);
goto restart_write;
}
if (ret == -1)
return (-1);
state->child_buf_avail += ret;
ret = (a->client_writer)(&a->archive, a->client_data,
state->child_buf, state->child_buf_avail);
if (ret <= 0)
return (-1);
if ((size_t)ret < state->child_buf_avail) {
memmove(state->child_buf, state->child_buf + ret,
state->child_buf_avail - ret);
}
state->child_buf_avail -= ret;
a->archive.raw_position += ret;
goto restart_write;
}
/*
* Write data to the compressed stream.
*/
static int
archive_compressor_program_write(struct archive_write *a, const void *buff,
size_t length)
{
struct private_data *state;
ssize_t ret;
const char *buf;
state = (struct private_data *)a->compressor.data;
if (a->client_writer == NULL) {
archive_set_error(&a->archive, ARCHIVE_ERRNO_PROGRAMMER,
"No write callback is registered? "
"This is probably an internal programming error.");
return (ARCHIVE_FATAL);
}
buf = buff;
while (length > 0) {
ret = child_write(a, buf, length);
if (ret == -1 || ret == 0) {
archive_set_error(&a->archive, EIO,
"Can't write to filter");
return (ARCHIVE_FATAL);
}
length -= ret;
buf += ret;
}
a->archive.file_position += length;
return (ARCHIVE_OK);
}
/*
* Finish the compression...
*/
static int
archive_compressor_program_finish(struct archive_write *a)
{
int ret, status;
ssize_t bytes_read, bytes_written;
struct private_data *state;
state = (struct private_data *)a->compressor.data;
ret = 0;
if (a->client_writer == NULL) {
archive_set_error(&a->archive, ARCHIVE_ERRNO_PROGRAMMER,
"No write callback is registered? "
"This is probably an internal programming error.");
ret = ARCHIVE_FATAL;
goto cleanup;
}
/* XXX pad compressed data. */
close(state->child_stdin);
state->child_stdin = -1;
fcntl(state->child_stdout, F_SETFL, 0);
for (;;) {
do {
bytes_read = read(state->child_stdout,
state->child_buf + state->child_buf_avail,
state->child_buf_len - state->child_buf_avail);
} while (bytes_read == -1 && errno == EINTR);
if (bytes_read == 0 || (bytes_read == -1 && errno == EPIPE))
break;
if (bytes_read == -1) {
archive_set_error(&a->archive, errno,
"Read from filter failed unexpectedly.");
ret = ARCHIVE_FATAL;
goto cleanup;
}
state->child_buf_avail += bytes_read;
bytes_written = (a->client_writer)(&a->archive, a->client_data,
state->child_buf, state->child_buf_avail);
if (bytes_written <= 0) {
ret = ARCHIVE_FATAL;
goto cleanup;
}
if ((size_t)bytes_written < state->child_buf_avail) {
memmove(state->child_buf,
state->child_buf + bytes_written,
state->child_buf_avail - bytes_written);
}
state->child_buf_avail -= bytes_written;
a->archive.raw_position += bytes_written;
}
/* XXX pad final compressed block. */
cleanup:
/* Shut down the child. */
if (state->child_stdin != -1)
close(state->child_stdin);
if (state->child_stdout != -1)
close(state->child_stdout);
while (waitpid(state->child, &status, 0) == -1 && errno == EINTR)
continue;
if (status != 0) {
archive_set_error(&a->archive, EIO,
"Filter exited with failure.");
ret = ARCHIVE_FATAL;
}
/* Release our configuration data. */
free(a->compressor.config);
a->compressor.config = NULL;
/* Release our private state data. */
free(state->child_buf);
free(state->description);
free(state);
return (ret);
}
#endif /* !defined(HAVE_PIPE) || !defined(HAVE_VFORK) || !defined(HAVE_FCNTL) */