Merge pull request #2558 from brauner/2018-08-21/pam_cgfs

src/lxc/Makefile.am

@@ -11,6 +11,7 @@ noinst_HEADERS = attach.h \
 		 confile_utils.h \
 		 criu.h \
 		 error.h \
+		 file_utils.h \
 		 initutils.h \
 		 list.h \
 		 log.h \
@@ -32,6 +33,7 @@ noinst_HEADERS = attach.h \
 		 storage/storage.h \
 		 storage/storage_utils.h \
 		 storage/zfs.h \
+		 string_utils.h \
 		 terminal.h \
 		 ../tests/lxctest.h \
 		 tools/arguments.h \
@@ -93,6 +95,7 @@ liblxc_la_SOURCES = af_unix.c af_unix.h \
 		    error.c error.h \
 		    execute.c \
 		    freezer.c \
+		    file_utils.c file_utils.h \
 		    initutils.c initutils.h \
 		    list.h \
 		    log.c log.h \
@@ -122,6 +125,7 @@ liblxc_la_SOURCES = af_unix.c af_unix.h \
 		    storage/storage.c storage/storage.h \
 		    storage/storage_utils.c storage/storage_utils.h \
 		    storage/zfs.c storage/zfs.h \
+		    string_utils.c string_utils.h \
 		    sync.c sync.h \
 		    terminal.c \
 		    utils.c utils.h \
@@ -319,7 +323,8 @@ endif
 
 if ENABLE_COMMANDS
 # Binaries shipping with liblxc
-init_lxc_SOURCES = cmd/lxc_init.c
+init_lxc_SOURCES = cmd/lxc_init.c \
+		   string_utils.c string_utils.h
 lxc_monitord_SOURCES = cmd/lxc_monitord.c
 lxc_user_nic_SOURCES = cmd/lxc_user_nic.c \
 		       log.c log.h \
@@ -332,6 +337,8 @@ lxc_usernsexec_SOURCES = cmd/lxc_usernsexec.c \
 			 log.c log.h \
 			 macro.h \
 			 namespace.c namespace.h \
+			 file_utils.c file_utils.h \
+			 string_utils.c string_utils.h \
 			 utils.c utils.h
 endif
 
@@ -350,10 +357,11 @@ init_lxc_static_SOURCES = cmd/lxc_init.c \
 			  caps.c caps.h \
 			  error.c error.h \
 			  initutils.c initutils.h \
+			  file_utils.c file_utils.h \
 			  log.c log.h \
 			  macro.h \
 			  namespace.c namespace.h \
-			  parse.c parse.h
+			  string_utils.c string_utils.h
 
 if !HAVE_GETLINE
 if HAVE_FGETLN
@@ -378,12 +386,27 @@ endif
 if ENABLE_PAM
 if HAVE_PAM
 pam_LTLIBRARIES = pam_cgfs.la
+
 pam_cgfs_la_SOURCES = pam/pam_cgfs.c \
-		      pam/utils.c pam/utils.h
-pam_cgfs_la_CFLAGS = $(AM_CFLAGS)
+		      macro.h \
+		      file_utils.c file_utils.h \
+		      string_utils.c string_utils.h
+
+if !HAVE_STRLCAT
+pam_cgfs_la_SOURCES += ../include/strlcat.c ../include/strlcat.h
+endif
+
+if !HAVE_STRLCPY
+pam_cgfs_la_SOURCES += ../include/strlcpy.c ../include/strlcpy.h
+endif
+
+pam_cgfs_la_CFLAGS = $(AM_CFLAGS) \
+		     -DNO_LOG
+
 pam_cgfs_la_LIBADD = $(AM_LIBS) \
 		     $(PAM_LIBS) \
 		     -L$(top_srcdir)
+
 pam_cgfs_la_LDFLAGS = $(AM_LDFLAGS) \
 		      -avoid-version \
 		      -module \

src/lxc/cmd/lxc_init.c

@@ -44,6 +44,7 @@
 #include "log.h"
 #include "namespace.h"
 #include "parse.h"
+#include "string_utils.h"
 
 /* option keys for long only options */
 #define OPT_USAGE 0x1000

src/lxc/file_utils.c

+/* liblxcapi
+ *
+ * Copyright © 2018 Christian Brauner <christian.brauner@ubuntu.com>.
+ * Copyright © 2018 Canonical Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2, as
+ * published by the Free Software Foundation.
+ *
+ * This program 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include "config.h"
+
+#include <errno.h>
+#include <fcntl.h>
+#include <linux/magic.h>
+#include <stdlib.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+
+#include "file_utils.h"
+#include "log.h"
+#include "macro.h"
+#include "string.h"
+
+#ifndef NO_LOG
+lxc_log_define(file_utils, lxc);
+#endif
+
+int lxc_write_to_file(const char *filename, const void *buf, size_t count,
+		      bool add_newline, mode_t mode)
+{
+	int fd, saved_errno;
+	ssize_t ret;
+
+	fd = open(filename, O_WRONLY | O_TRUNC | O_CREAT | O_CLOEXEC, mode);
+	if (fd < 0)
+		return -1;
+
+	ret = lxc_write_nointr(fd, buf, count);
+	if (ret < 0)
+		goto out_error;
+
+	if ((size_t)ret != count)
+		goto out_error;
+
+	if (add_newline) {
+		ret = lxc_write_nointr(fd, "\n", 1);
+		if (ret != 1)
+			goto out_error;
+	}
+
+	close(fd);
+	return 0;
+
+out_error:
+	saved_errno = errno;
+	close(fd);
+	errno = saved_errno;
+	return -1;
+}
+
+int lxc_read_from_file(const char *filename, void *buf, size_t count)
+{
+	int fd = -1, saved_errno;
+	ssize_t ret;
+
+	fd = open(filename, O_RDONLY | O_CLOEXEC);
+	if (fd < 0)
+		return -1;
+
+	if (!buf || !count) {
+		char buf2[100];
+		size_t count2 = 0;
+
+		while ((ret = lxc_read_nointr(fd, buf2, 100)) > 0)
+			count2 += ret;
+
+		if (ret >= 0)
+			ret = count2;
+	} else {
+		memset(buf, 0, count);
+		ret = lxc_read_nointr(fd, buf, count);
+	}
+
+	saved_errno = errno;
+	close(fd);
+	errno = saved_errno;
+	return ret;
+}
+
+ssize_t lxc_write_nointr(int fd, const void *buf, size_t count)
+{
+	ssize_t ret;
+again:
+	ret = write(fd, buf, count);
+	if (ret < 0 && errno == EINTR)
+		goto again;
+
+	return ret;
+}
+
+ssize_t lxc_read_nointr(int fd, void *buf, size_t count)
+{
+	ssize_t ret;
+again:
+	ret = read(fd, buf, count);
+	if (ret < 0 && errno == EINTR)
+		goto again;
+
+	return ret;
+}
+
+ssize_t lxc_read_nointr_expect(int fd, void *buf, size_t count, const void *expected_buf)
+{
+	ssize_t ret;
+
+	ret = lxc_read_nointr(fd, buf, count);
+	if (ret <= 0)
+		return ret;
+
+	if ((size_t)ret != count)
+		return -1;
+
+	if (expected_buf && memcmp(buf, expected_buf, count) != 0) {
+		errno = EINVAL;
+		return -1;
+	}
+
+	return ret;
+}
+
+bool file_exists(const char *f)
+{
+	struct stat statbuf;
+
+	return stat(f, &statbuf) == 0;
+}
+
+int print_to_file(const char *file, const char *content)
+{
+	FILE *f;
+	int ret = 0;
+
+	f = fopen(file, "w");
+	if (!f)
+		return -1;
+
+	if (fprintf(f, "%s", content) != strlen(content))
+		ret = -1;
+
+	fclose(f);
+	return ret;
+}
+
+int is_dir(const char *path)
+{
+	struct stat statbuf;
+	int ret;
+
+	ret = stat(path, &statbuf);
+	if (ret == 0 && S_ISDIR(statbuf.st_mode))
+		return 1;
+
+	return 0;
+}
+
+/*
+ * Return the number of lines in file @fn, or -1 on error
+ */
+int lxc_count_file_lines(const char *fn)
+{
+	FILE *f;
+	char *line = NULL;
+	size_t sz = 0;
+	int n = 0;
+
+	f = fopen_cloexec(fn, "r");
+	if (!f)
+		return -1;
+
+	while (getline(&line, &sz, f) != -1) {
+		n++;
+	}
+
+	free(line);
+	fclose(f);
+	return n;
+}
+
+int lxc_make_tmpfile(char *template, bool rm)
+{
+	int fd, ret;
+	mode_t msk;
+
+	msk = umask(0022);
+	fd = mkstemp(template);
+	umask(msk);
+	if (fd < 0)
+		return -1;
+
+	if (!rm)
+		return fd;
+
+	ret = unlink(template);
+	if (ret < 0) {
+		close(fd);
+		return -1;
+	}
+
+	return fd;
+}
+
+/* In overlayfs, st_dev is unreliable. So on overlayfs we don't do the
+ * lxc_rmdir_onedev()
+ */
+static bool is_native_overlayfs(const char *path)
+{
+	if (has_fs_type(path, OVERLAY_SUPER_MAGIC) ||
+	    has_fs_type(path, OVERLAYFS_SUPER_MAGIC))
+		return true;
+
+	return false;
+}
+
+bool is_fs_type(const struct statfs *fs, fs_type_magic magic_val)
+{
+	return (fs->f_type == (fs_type_magic)magic_val);
+}
+
+bool has_fs_type(const char *path, fs_type_magic magic_val)
+{
+	bool has_type;
+	int ret;
+	struct statfs sb;
+
+	ret = statfs(path, &sb);
+	if (ret < 0)
+		return false;
+
+	return is_fs_type(&sb, magic_val);
+}
+
+bool fhas_fs_type(int fd, fs_type_magic magic_val)
+{
+	int ret;
+	struct statfs sb;
+
+	ret = fstatfs(fd, &sb);
+	if (ret < 0)
+		return false;
+
+	return is_fs_type(&sb, magic_val);
+}
+
+FILE *fopen_cloexec(const char *path, const char *mode)
+{
+	int open_mode = 0;
+	int step = 0;
+	int fd;
+	int saved_errno = 0;
+	FILE *ret;
+
+	if (!strncmp(mode, "r+", 2)) {
+		open_mode = O_RDWR;
+		step = 2;
+	} else if (!strncmp(mode, "r", 1)) {
+		open_mode = O_RDONLY;
+		step = 1;
+	} else if (!strncmp(mode, "w+", 2)) {
+		open_mode = O_RDWR | O_TRUNC | O_CREAT;
+		step = 2;
+	} else if (!strncmp(mode, "w", 1)) {
+		open_mode = O_WRONLY | O_TRUNC | O_CREAT;
+		step = 1;
+	} else if (!strncmp(mode, "a+", 2)) {
+		open_mode = O_RDWR | O_CREAT | O_APPEND;
+		step = 2;
+	} else if (!strncmp(mode, "a", 1)) {
+		open_mode = O_WRONLY | O_CREAT | O_APPEND;
+		step = 1;
+	}
+	for (; mode[step]; step++)
+		if (mode[step] == 'x')
+			open_mode |= O_EXCL;
+	open_mode |= O_CLOEXEC;
+
+	fd = open(path, open_mode, 0666);
+	if (fd < 0)
+		return NULL;
+
+	ret = fdopen(fd, mode);
+	saved_errno = errno;
+	if (!ret)
+		close(fd);
+	errno = saved_errno;
+	return ret;
+}

src/lxc/file_utils.h

+/* liblxcapi
+ *
+ * Copyright © 2018 Christian Brauner <christian.brauner@ubuntu.com>.
+ * Copyright © 2018 Canonical Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2, as
+ * published by the Free Software Foundation.
+ *
+ * This program 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#ifndef __LXC_FILE_UTILS_H
+#define __LXC_FILE_UTILS_H
+
+#include "config.h"
+
+#include <fcntl.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <sys/vfs.h>
+#include <unistd.h>
+
+/* read and write whole files */
+extern int lxc_write_to_file(const char *filename, const void *buf,
+			     size_t count, bool add_newline, mode_t mode);
+extern int lxc_read_from_file(const char *filename, void *buf, size_t count);
+
+/* send and receive buffers completely */
+extern ssize_t lxc_write_nointr(int fd, const void *buf, size_t count);
+extern ssize_t lxc_read_nointr(int fd, void *buf, size_t count);
+extern ssize_t lxc_read_nointr_expect(int fd, void *buf, size_t count,
+				      const void *expected_buf);
+extern bool file_exists(const char *f);
+extern int print_to_file(const char *file, const char *content);
+extern int is_dir(const char *path);
+extern int lxc_count_file_lines(const char *fn);
+extern int lxc_make_tmpfile(char *template, bool rm);
+
+/* __typeof__ should be safe to use with all compilers. */
+typedef __typeof__(((struct statfs *)NULL)->f_type) fs_type_magic;
+extern bool has_fs_type(const char *path, fs_type_magic magic_val);
+extern bool fhas_fs_type(int fd, fs_type_magic magic_val);
+extern bool is_fs_type(const struct statfs *fs, fs_type_magic magic_val);
+extern FILE *fopen_cloexec(const char *path, const char *mode);
+
+#endif /* __LXC_FILE_UTILS_H */

src/lxc/freezer.c

@@ -37,8 +37,8 @@
 #include "log.h"
 #include "lxc.h"
 #include "monitor.h"
-#include "parse.h"
 #include "state.h"
+#include "string_utils.h"
 
 lxc_log_define(freezer, lxc);
 

src/lxc/initutils.c

@@ -24,6 +24,7 @@
 #define _GNU_SOURCE
 #include <sys/prctl.h>
 
+#include "file_utils.h"
 #include "initutils.h"
 #include "log.h"
 #include "macro.h"
@@ -223,50 +224,6 @@ extern void remove_trailing_slashes(char *p)
 		p[l] = '\0';
 }
 
-FILE *fopen_cloexec(const char *path, const char *mode)
-{
-	int open_mode = 0;
-	int step = 0;
-	int fd;
-	int saved_errno = 0;
-	FILE *ret;
-
-	if (!strncmp(mode, "r+", 2)) {
-		open_mode = O_RDWR;
-		step = 2;
-	} else if (!strncmp(mode, "r", 1)) {
-		open_mode = O_RDONLY;
-		step = 1;
-	} else if (!strncmp(mode, "w+", 2)) {
-		open_mode = O_RDWR | O_TRUNC | O_CREAT;
-		step = 2;
-	} else if (!strncmp(mode, "w", 1)) {
-		open_mode = O_WRONLY | O_TRUNC | O_CREAT;
-		step = 1;
-	} else if (!strncmp(mode, "a+", 2)) {
-		open_mode = O_RDWR | O_CREAT | O_APPEND;
-		step = 2;
-	} else if (!strncmp(mode, "a", 1)) {
-		open_mode = O_WRONLY | O_CREAT | O_APPEND;
-		step = 1;
-	}
-	for (; mode[step]; step++)
-		if (mode[step] == 'x')
-			open_mode |= O_EXCL;
-	open_mode |= O_CLOEXEC;
-
-	fd = open(path, open_mode, 0666);
-	if (fd < 0)
-		return NULL;
-
-	ret = fdopen(fd, mode);
-	saved_errno = errno;
-	if (!ret)
-		close(fd);
-	errno = saved_errno;
-	return ret;
-}
-
 /*
  * Sets the process title to the specified title. Note that this may fail if
  * the kernel doesn't support PR_SET_MM_MAP (kernels <3.18).

src/lxc/initutils.h

@@ -72,7 +72,6 @@ extern const char *lxc_global_config_value(const char *option_name);
 
 /* open a file with O_CLOEXEC */
 extern void remove_trailing_slashes(char *p);
-extern FILE *fopen_cloexec(const char *path, const char *mode);
 extern int setproctitle(char *title);
 
 #endif /* __LXC_INITUTILS_H */

src/lxc/macro.h

@@ -79,6 +79,15 @@
 #define NSFS_MAGIC 0x6e736673
 #endif
 
+/* We have two different magic values for overlayfs, yay. */
+#ifndef OVERLAYFS_SUPER_MAGIC
+#define OVERLAYFS_SUPER_MAGIC 0x794c764f
+#endif
+
+#ifndef OVERLAY_SUPER_MAGIC
+#define OVERLAY_SUPER_MAGIC 0x794c7630
+#endif
+
 /* Useful macros */
 /* Maximum number for 64 bit integer is a string with 21 digits: 2^64 - 1 = 21 */
 #define LXC_NUMSTRLEN64 21
@@ -222,4 +231,13 @@ extern int __build_bug_on_failed;
 #define MS_SLAVE (1 << 19)
 #endif
 
+/* open */
+#ifndef O_PATH
+#define O_PATH      010000000
+#endif
+
+#ifndef O_NOFOLLOW
+#define O_NOFOLLOW  00400000
+#endif
+
 #endif /* __LXC_MACRO_H */

src/lxc/pam/pam_cgfs.c

@@ -57,6 +57,7 @@
 #include <security/_pam_macros.h>
 #include <security/pam_modules.h>
 
+#include "macro.h"
 #include "utils.h"
 
 #ifndef HAVE_STRLCPY

src/lxc/pam/utils.c

-/*
- * 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
- */
-
-
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <unistd.h>
-#include <stdlib.h>
-#include <stdbool.h>
-#include <string.h>
-#include <sys/vfs.h>
-#include <stdarg.h>
-
-#include "utils.h"
-
-#ifndef HAVE_STRLCAT
-#include "include/strlcat.h"
-#endif
-
-bool file_exists(const char *f)
-{
-	struct stat statbuf;
-
-	return stat(f, &statbuf) == 0;
-}
-
-void *must_realloc(void *orig, size_t sz)
-{
-	void *ret;
-
-	do {
-		ret = realloc(orig, sz);
-	} while (!ret);
-
-	return ret;
-}
-
-char *must_copy_string(const char *entry)
-{
-	char *ret;
-
-	if (!entry)
-		return NULL;
-	do {
-		ret = strdup(entry);
-	} while (!ret);
-
-	return ret;
-}
-
-char *must_make_path(const char *first, ...)
-{
-	va_list args;
-	char *cur, *dest;
-	size_t full_len = strlen(first);
-	size_t buf_len;
-
-	dest = must_copy_string(first);
-
-	va_start(args, first);
-	while ((cur = va_arg(args, char *)) != NULL) {
-		full_len += strlen(cur);
-		if (cur[0] != '/')
-			full_len++;
-
-		buf_len = full_len + 1;
-		dest = must_realloc(dest, buf_len);
-
-		if (cur[0] != '/')
-			(void)strlcat(dest, "/", buf_len);
-		(void)strlcat(dest, cur, buf_len);
-	}
-	va_end(args);
-
-	return dest;
-}
-
-bool is_fs_type(const struct statfs *fs, fs_type_magic magic_val)
-{
-	return (fs->f_type == (fs_type_magic)magic_val);
-}
-
-bool has_fs_type(const char *path, fs_type_magic magic_val)
-{
-	bool has_type;
-	int ret;
-	struct statfs sb;
-
-	ret = statfs(path, &sb);
-	if (ret < 0)
-		return false;
-
-	has_type = is_fs_type(&sb, magic_val);
-
-	return has_type;
-}

src/lxc/pam/utils.h

-/*
- * 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 __PAM_UTILS_H
-#define __PAM_UTILS_H
-
-#include <sys/vfs.h>
-
-#ifndef CGROUP_SUPER_MAGIC
-#define CGROUP_SUPER_MAGIC 0x27e0eb
-#endif
-
-#ifndef CGROUP2_SUPER_MAGIC
-#define CGROUP2_SUPER_MAGIC 0x63677270
-#endif
-
-typedef __typeof__(((struct statfs *)NULL)->f_type) fs_type_magic;
-extern bool file_exists(const char *f);
-extern void *must_realloc(void *orig, size_t sz);
-extern char *must_copy_string(const char *entry);
-__attribute__((sentinel)) extern char *must_make_path(const char *first, ...);
-extern bool has_fs_type(const char *path, fs_type_magic magic_val);
-
-#endif /* __PAM_UTILS_H */

src/lxc/parse.c

@@ -139,55 +139,3 @@ int lxc_file_for_each_line(const char *file, lxc_file_cb callback, void *data)
 	fclose(f);
 	return err;
 }
-
-int lxc_char_left_gc(const char *buffer, size_t len)
-{
-	size_t i;
-
-	for (i = 0; i < len; i++) {
-		if (buffer[i] == ' ' ||
-		    buffer[i] == '\t')
-			continue;
-
-		return i;
-	}
-
-	return 0;
-}
-
-int lxc_char_right_gc(const char *buffer, size_t len)
-{
-	int i;
-
-	for (i = len - 1; i >= 0; i--) {
-		if (buffer[i] == ' '  ||
-		    buffer[i] == '\t' ||
-		    buffer[i] == '\n' ||
-		    buffer[i] == '\0')
-			continue;
-
-		return i + 1;
-	}
-
-	return 0;
-}
-
-char *lxc_trim_whitespace_in_place(char *buffer)
-{
-	buffer += lxc_char_left_gc(buffer, strlen(buffer));
-	buffer[lxc_char_right_gc(buffer, strlen(buffer))] = '\0';
-	return buffer;
-}
-
-int lxc_is_line_empty(const char *line)
-{
-	int i;
-	size_t len = strlen(line);
-
-	for (i = 0; i < len; i++)
-		if (line[i] != ' ' && line[i] != '\t' &&
-		    line[i] != '\n' && line[i] != '\r' &&
-		    line[i] != '\f' && line[i] != '\0')
-			return 0;
-	return 1;
-}

src/lxc/parse.h

@@ -37,14 +37,6 @@ extern int lxc_file_for_each_line(const char *file, lxc_file_cb callback,
 extern int lxc_file_for_each_line_mmap(const char *file, lxc_file_cb callback,
 				       void *data);
 
-extern int lxc_char_left_gc(const char *buffer, size_t len);
-
-extern int lxc_char_right_gc(const char *buffer, size_t len);
-
-extern char *lxc_trim_whitespace_in_place(char *buffer);
-
-extern int lxc_is_line_empty(const char *line);
-
 /* mmap() wrapper. lxc_strmmap() will take care to \0-terminate files so that
  * normal string-handling functions can be used on the buffer. */
 extern void *lxc_strmmap(void *addr, size_t length, int prot, int flags, int fd,

src/lxc/string_utils.h

+/* liblxcapi
+ *
+ * Copyright © 2018 Christian Brauner <christian.brauner@ubuntu.com>.
+ * Copyright © 2018 Canonical Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2, as
+ * published by the Free Software Foundation.
+ *
+ * This program 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#ifndef __LXC_STRING_UTILS_H
+#define __LXC_STRING_UTILS_H
+
+#include "config.h"
+
+#include <errno.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdbool.h>
+#include <unistd.h>
+#include <linux/loop.h>
+#include <linux/magic.h>
+#include <linux/types.h>
+#include <sys/syscall.h>
+#include <sys/types.h>
+#include <sys/vfs.h>
+
+#ifdef HAVE_LINUX_MEMFD_H
+#include <linux/memfd.h>
+#endif
+
+#include "initutils.h"
+#include "macro.h"
+
+/* convert variadic argument lists to arrays (for execl type argument lists) */
+extern char **lxc_va_arg_list_to_argv(va_list ap, size_t skip, int do_strdup);
+extern const char **lxc_va_arg_list_to_argv_const(va_list ap, size_t skip);
+
+/*
+ * Some simple string functions; if they return pointers, they are allocated
+ * buffers.
+ */
+extern char *lxc_string_replace(const char *needle, const char *replacement,
+				const char *haystack);
+extern bool lxc_string_in_array(const char *needle, const char **haystack);
+extern char *lxc_string_join(const char *sep, const char **parts,
+			     bool use_as_prefix);
+/*
+ * Normalize and split path: Leading and trailing / are removed, multiple
+ * / are compactified, .. and . are resolved (.. on the top level is considered
+ * identical to .).
+ * Examples:
+ *     /            ->   { NULL }
+ *     foo/../bar   ->   { bar, NULL }
+ *     ../../       ->   { NULL }
+ *     ./bar/baz/.. ->   { bar, NULL }
+ *     foo//bar     ->   { foo, bar, NULL }
+ */
+extern char **lxc_normalize_path(const char *path);
+
+/* remove multiple slashes from the path, e.g. ///foo//bar -> /foo/bar */
+extern char *lxc_deslashify(const char *path);
+extern char *lxc_append_paths(const char *first, const char *second);
+
+/*
+ * Note: the following two functions use strtok(), so they will never
+ *       consider an empty element, even if two delimiters are next to
+ *       each other.
+ */
+extern bool lxc_string_in_list(const char *needle, const char *haystack,
+			       char sep);
+extern char **lxc_string_split(const char *string, char sep);
+extern char **lxc_string_split_and_trim(const char *string, char sep);
+extern char **lxc_string_split_quoted(char *string);
+
+/* Append string to NULL-terminated string array. */
+extern int lxc_append_string(char ***list, char *entry);
+
+/* Some simple array manipulation utilities */
+typedef void (*lxc_free_fn)(void *);
+typedef void *(*lxc_dup_fn)(void *);
+extern int lxc_grow_array(void ***array, size_t *capacity, size_t new_size,
+			  size_t capacity_increment);
+extern void lxc_free_array(void **array, lxc_free_fn element_free_fn);
+extern size_t lxc_array_len(void **array);
+
+extern void **lxc_append_null_to_array(void **array, size_t count);
+extern void remove_trailing_newlines(char *l);
+
+/* Helper functions to parse numbers. */
+extern int lxc_safe_uint(const char *numstr, unsigned int *converted);
+extern int lxc_safe_int(const char *numstr, int *converted);
+extern int lxc_safe_long(const char *numstr, long int *converted);
+extern int lxc_safe_long_long(const char *numstr, long long int *converted);
+extern int lxc_safe_ulong(const char *numstr, unsigned long *converted);
+extern int lxc_safe_uint64(const char *numstr, uint64_t *converted, int base);
+/* Handles B, kb, MB, GB. Detects overflows and reports -ERANGE. */
+extern int parse_byte_size_string(const char *s, int64_t *converted);
+
+/*
+ * Concatenate all passed-in strings into one path. Do not fail. If any piece
+ * is not prefixed with '/', add a '/'.
+ */
+__attribute__((sentinel)) extern char *must_concat(const char *first, ...);
+__attribute__((sentinel)) extern char *must_make_path(const char *first, ...);
+__attribute__((sentinel)) extern char *must_append_path(char *first, ...);
+
+/* Return copy of string @entry. Do not fail. */
+extern char *must_copy_string(const char *entry);
+
+/* Re-alllocate a pointer, do not fail */
+extern void *must_realloc(void *orig, size_t sz);
+
+extern int lxc_char_left_gc(const char *buffer, size_t len);
+
+extern int lxc_char_right_gc(const char *buffer, size_t len);
+
+extern char *lxc_trim_whitespace_in_place(char *buffer);
+
+extern int lxc_is_line_empty(const char *line);
+
+#endif /* __LXC_STRING_UTILS_H */

src/lxc/utils.h

@@ -34,7 +34,6 @@
 #include <stdbool.h>
 #include <unistd.h>
 #include <linux/loop.h>
-#include <linux/magic.h>
 #include <linux/types.h>
 #include <sys/syscall.h>
 #include <sys/types.h>
@@ -44,8 +43,10 @@
 #include <linux/memfd.h>
 #endif
 
+#include "file_utils.h"
 #include "initutils.h"
 #include "macro.h"
+#include "string_utils.h"
 
 /* returns 1 on success, 0 if there were any failures */
 extern int lxc_rmdir_onedev(const char *path, const char *exclude);
@@ -281,70 +282,11 @@ extern int lxc_pclose(struct lxc_popen_FILE *fp);
 extern int wait_for_pid(pid_t pid);
 extern int lxc_wait_for_pid_status(pid_t pid);
 
-/* send and receive buffers completely */
-extern ssize_t lxc_write_nointr(int fd, const void *buf, size_t count);
-extern ssize_t lxc_read_nointr(int fd, void *buf, size_t count);
-extern ssize_t lxc_read_nointr_expect(int fd, void *buf, size_t count,
-				      const void *expected_buf);
 #if HAVE_LIBGNUTLS
 #define SHA_DIGEST_LENGTH 20
 extern int sha1sum_file(char *fnam, unsigned char *md_value);
 #endif
 
-/* read and write whole files */
-extern int lxc_write_to_file(const char *filename, const void *buf,
-			     size_t count, bool add_newline, mode_t mode);
-extern int lxc_read_from_file(const char *filename, void *buf, size_t count);
-
-/* convert variadic argument lists to arrays (for execl type argument lists) */
-extern char** lxc_va_arg_list_to_argv(va_list ap, size_t skip, int do_strdup);
-extern const char** lxc_va_arg_list_to_argv_const(va_list ap, size_t skip);
-
-/* Some simple string functions; if they return pointers, they are allocated
- * buffers.
- */
-extern char *lxc_string_replace(const char *needle, const char *replacement,
-				const char *haystack);
-extern bool lxc_string_in_array(const char *needle, const char **haystack);
-extern char *lxc_string_join(const char *sep, const char **parts,
-			     bool use_as_prefix);
-/* Normalize and split path: Leading and trailing / are removed, multiple
- * / are compactified, .. and . are resolved (.. on the top level is considered
- * identical to .).
- * Examples:
- *     /            ->   { NULL }
- *     foo/../bar   ->   { bar, NULL }
- *     ../../       ->   { NULL }
- *     ./bar/baz/.. ->   { bar, NULL }
- *     foo//bar     ->   { foo, bar, NULL }
- */
-extern char **lxc_normalize_path(const char *path);
-/* remove multiple slashes from the path, e.g. ///foo//bar -> /foo/bar */
-extern char *lxc_deslashify(const char *path);
-extern char *lxc_append_paths(const char *first, const char *second);
-/* Note: the following two functions use strtok(), so they will never
- *       consider an empty element, even if two delimiters are next to
- *       each other.
- */
-extern bool lxc_string_in_list(const char *needle, const char *haystack,
-			       char sep);
-extern char **lxc_string_split(const char *string, char sep);
-extern char **lxc_string_split_and_trim(const char *string, char sep);
-extern char **lxc_string_split_quoted(char *string);
-/* Append string to NULL-terminated string array. */
-extern int lxc_append_string(char ***list, char *entry);
-
-/* some simple array manipulation utilities */
-typedef void (*lxc_free_fn)(void *);
-typedef void *(*lxc_dup_fn)(void *);
-extern int lxc_grow_array(void ***array, size_t *capacity, size_t new_size,
-			  size_t capacity_increment);
-extern void lxc_free_array(void **array, lxc_free_fn element_free_fn);
-extern size_t lxc_array_len(void **array);
-
-extern void **lxc_append_null_to_array(void **array, size_t count);
-extern void remove_trailing_newlines(char *l);
-
 /* initialize rand with urandom */
 extern int randseed(bool);
 
@@ -396,12 +338,9 @@ extern bool is_shared_mountpoint(const char *path);
 extern int detect_shared_rootfs(void);
 extern bool detect_ramfs_rootfs(void);
 extern char *on_path(const char *cmd, const char *rootfs);
-extern bool file_exists(const char *f);
 extern bool cgns_supported(void);
 extern char *choose_init(const char *rootfs);
-extern int print_to_file(const char *file, const char *content);
 extern bool switch_to_ns(pid_t pid, const char *ns);
-extern int is_dir(const char *path);
 extern char *get_template_path(const char *t);
 extern int safe_mount(const char *src, const char *dest, const char *fstype,
 		      unsigned long flags, const void *data,
@@ -410,22 +349,11 @@ extern int lxc_mount_proc_if_needed(const char *rootfs);
 extern int open_devnull(void);
 extern int set_stdfds(int fd);
 extern int null_stdfds(void);
-extern int lxc_count_file_lines(const char *fn);
 extern int lxc_preserve_ns(const int pid, const char *ns);
 
 /* Check whether a signal is blocked by a process. */
 extern bool task_blocks_signal(pid_t pid, int signal);
 
-/* Helper functions to parse numbers. */
-extern int lxc_safe_uint(const char *numstr, unsigned int *converted);
-extern int lxc_safe_int(const char *numstr, int *converted);
-extern int lxc_safe_long(const char *numstr, long int *converted);
-extern int lxc_safe_long_long(const char *numstr, long long int *converted);
-extern int lxc_safe_ulong(const char *numstr, unsigned long *converted);
-extern int lxc_safe_uint64(const char *numstr, uint64_t *converted, int base);
-/* Handles B, kb, MB, GB. Detects overflows and reports -ERANGE. */
-extern int parse_byte_size_string(const char *s, int64_t *converted);
-
 /* Switch to a new uid and gid. */
 extern int lxc_switch_uid_gid(uid_t uid, gid_t gid);
 extern int lxc_setgroups(int size, gid_t list[]);
@@ -468,13 +396,7 @@ extern char *must_copy_string(const char *entry);
 /* Re-alllocate a pointer, do not fail */
 extern void *must_realloc(void *orig, size_t sz);
 
-/* __typeof__ should be safe to use with all compilers. */
-typedef __typeof__(((struct statfs *)NULL)->f_type) fs_type_magic;
-extern bool has_fs_type(const char *path, fs_type_magic magic_val);
-extern bool fhas_fs_type(int fd, fs_type_magic magic_val);
-extern bool is_fs_type(const struct statfs *fs, fs_type_magic magic_val);
 extern bool lxc_nic_exists(char *nic);
-extern int lxc_make_tmpfile(char *template, bool rm);
 
 static inline uint64_t lxc_getpagesize(void)
 {