-/*
- * lxc: linux Container library
- *
- * (C) Copyright IBM Corp. 2007, 2008
- *
- * Authors:
- * Daniel Lezcano <daniel.lezcano at free.fr>
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; either
- * version 2.1 of the License, or (at your option) any later version.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
- */
-
-#ifndef _GNU_SOURCE
-#define _GNU_SOURCE 1
-#endif
+/* SPDX-License-Identifier: LGPL-2.1+ */
+
+#include "config.h"
+
#include <dirent.h>
#include <errno.h>
+#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/mman.h>
+#include <sys/sendfile.h>
-#include "config.h"
+#include "file_utils.h"
#include "log.h"
+#include "macro.h"
#include "parse.h"
+#include "syscall_wrappers.h"
#include "utils.h"
lxc_log_define(parse, lxc);
int lxc_file_for_each_line_mmap(const char *file, lxc_file_cb callback, void *data)
{
- int fd, saved_errno;
- char *buf, *line;
- struct stat st;
- int ret = 0;
+ __do_close int fd = -EBADF, memfd = -EBADF;
+ ssize_t ret = -1;
+ char *buf = NULL;
+ struct stat st = {};
+ ssize_t bytes;
+ char *line;
+
+ memfd = memfd_create(".lxc_config_file", MFD_CLOEXEC);
+ if (memfd < 0) {
+ char template[] = P_tmpdir "/.lxc_config_file_XXXXXX";
+
+ if (errno != ENOSYS) {
+ SYSERROR("Failed to create memory file");
+ goto on_error;
+ }
+
+ TRACE("Failed to create in-memory file. Falling back to temporary file");
+ memfd = lxc_make_tmpfile(template, true);
+ if (memfd < 0) {
+ SYSERROR("Failed to create temporary file \"%s\"", template);
+ goto on_error;
+ }
+ }
fd = open(file, O_RDONLY | O_CLOEXEC);
if (fd < 0) {
- SYSERROR("Failed to open config file \"%s\"", file);
- return -1;
+ SYSERROR("Failed to open file \"%s\"", file);
+ goto on_error;
}
ret = fstat(fd, &st);
+ if (ret) {
+ SYSERROR("Failed to stat file \"%s\"", file);
+ goto on_error;
+ }
+
+ if (st.st_size > INT_MAX) {
+ SYSERROR("Excessively large config file \"%s\"", file);
+ goto on_error;
+ }
+
+
+ bytes = __fd_to_fd(fd, memfd);
+ if (bytes < 0) {
+ SYSERROR("Failed to copy config file \"%s\"", file);
+ goto on_error;
+ }
+
+ ret = lxc_write_nointr(memfd, "\0", 1);
if (ret < 0) {
- SYSERROR("Failed to stat config file \"%s\"", file);
+ SYSERROR("Failed to append zero byte");
goto on_error;
}
+ bytes++;
- ret = 0;
- if (st.st_size == 0)
+ ret = lseek(memfd, 0, SEEK_SET);
+ if (ret < 0) {
+ SYSERROR("Failed to lseek");
goto on_error;
+ }
ret = -1;
- buf = lxc_strmmap(NULL, st.st_size, PROT_READ | PROT_WRITE,
- MAP_PRIVATE | MAP_POPULATE, fd, 0);
+ buf = mmap(NULL, bytes, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_POPULATE, memfd, 0);
if (buf == MAP_FAILED) {
- SYSERROR("Failed to map config file \"%s\"", file);
+ buf = NULL;
+ SYSERROR("Failed to mmap");
goto on_error;
}
- lxc_iterate_parts(line, buf, "\n\0") {
+ ret = 0;
+ lxc_iterate_parts(line, buf, "\r\n\0") {
ret = callback(line, data);
if (ret) {
/* Callback rv > 0 means stop here callback rv < 0 means
* error.
*/
if (ret < 0)
- ERROR("Failed to parse config file \"%s\" at "
- "line \"%s\"",
+ ERROR("Failed to parse config file \"%s\" at line \"%s\"",
file, line);
break;
}
}
on_error:
- if (lxc_strmunmap(buf, st.st_size) < 0) {
- SYSERROR("Failed to unmap config file \"%s\"", file);
+ if (buf && munmap(buf, bytes)) {
+ SYSERROR("Failed to unmap");
if (ret == 0)
ret = -1;
}
- saved_errno = errno;
- close(fd);
- errno = saved_errno;
-
return ret;
}
int lxc_file_for_each_line(const char *file, lxc_file_cb callback, void *data)
{
- FILE *f;
+ __do_fclose FILE *f = NULL;
+ __do_free char *line = NULL;
int err = 0;
- char *line = NULL;
size_t len = 0;
- f = fopen(file, "r");
+ f = fopen(file, "re");
if (!f) {
- SYSERROR("failed to open %s", file);
+ SYSERROR("Failed to open \"%s\"", file);
return -1;
}
* error.
*/
if (err < 0)
- ERROR("Failed to parse config: %s", line);
+ ERROR("Failed to parse config: \"%s\"", line);
break;
}
}
- free(line);
- fclose(f);
return err;
}