libmount: add basic utils

Signed-off-by: Karel Zak <kzak@redhat.com>

6 files changed, 239 insertions, 2 deletions

diff --git a/configure.ac b/configure.ac
index af92980ec..117564098 100644
--- a/configure.ac
+++ b/configure.ac
@@ -188,6 +188,9 @@ AC_CHECK_FUNCS(
 	srandom \
 	setresgid \
 	setresuid \
+	strndup \
+	strnlen \
+	strnchr \
 	inotify_init \
 	prctl \
 	posix_fadvise \
diff --git a/shlibs/mount/src/Makefile.am b/shlibs/mount/src/Makefile.am
index 7b3aaaf09..2ac06bd35 100644
--- a/shlibs/mount/src/Makefile.am
+++ b/shlibs/mount/src/Makefile.am
@@ -12,7 +12,8 @@ usrlib_exec_LTLIBRARIES = libmount.la
 libmount_la_SOURCES = $(mountinc_HEADERS)
 
 nodist_libmount_la_SOURCES = mount.h \
-			     version.c
+			     version.c \
+			     utils.c
 
 libmount_la_LIBADD = $(ul_libblkid_la)
 
diff --git a/shlibs/mount/src/mount.h.in b/shlibs/mount/src/mount.h.in
index 9767a0a98..6990e5ceb 100644
--- a/shlibs/mount/src/mount.h.in
+++ b/shlibs/mount/src/mount.h.in
@@ -31,6 +31,11 @@ extern "C" {
 extern int mnt_parse_version_string(const char *ver_string);
 extern int mnt_get_library_version(const char **ver_string);
 
+/* utils.c */
+extern int mnt_fstype_is_netfs(const char *type);
+extern int mnt_fstype_is_pseudofs(const char *type);
+extern int mnt_open_device(const char *devname, int flags);
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/shlibs/mount/src/mount.sym b/shlibs/mount/src/mount.sym
index cf6907a98..0f2fc6b7d 100644
--- a/shlibs/mount/src/mount.sym
+++ b/shlibs/mount/src/mount.sym
@@ -5,7 +5,10 @@
  */
 MOUNT_2.18 {
 global:
+	mnt_fstype_is_netfs;
+	mnt_fstype_is_pseudofs;
 	mnt_get_library_version;
+	mnt_open_device;
 	mnt_parse_version_string;
 local:
 	*;
diff --git a/shlibs/mount/src/mountP.h b/shlibs/mount/src/mountP.h
index 2a486f02a..172341349 100644
--- a/shlibs/mount/src/mountP.h
+++ b/shlibs/mount/src/mountP.h
@@ -10,12 +10,29 @@
 #ifndef _LIBMOUNT_PRIVATE_H
 #define _LIBMOUNT_PRIVATE_H
 
+#include <sys/types.h>
+#include "mount.h"
+
 /* features */
+#define CONFIG_CDROM_NOMEDIUM_RETRIES    5
 #define CONFIG_LIBMOUNT_ASSERT
 
 #ifdef CONFIG_LIBMOUNT_ASSERT
 #include <assert.h>
 #endif
 
-#include "mount.h"
+/* utils.c */
+extern char *mnt_getenv_safe(const char *arg);
+#ifndef HAVE_STRNLEN
+extern size_t strnlen(const char *s, size_t maxlen);
+#endif
+#ifndef HAVE_STRNDUP
+extern char *strndup(const char *s, size_t n);
+#endif
+#ifndef HAVE_STRNCHR
+extern char *strnchr(const char *s, size_t maxlen, int c);
+#endif
+extern char *mnt_get_username(const uid_t uid);
+extern char *mnt_strconcat3(char *s, const char *t, const char *u);
+
 #endif
diff --git a/shlibs/mount/src/utils.c b/shlibs/mount/src/utils.c
new file mode 100644
index 000000000..fbdfadb84
--- /dev/null
+++ b/shlibs/mount/src/utils.c
@@ -0,0 +1,208 @@
+/*
+ * Copyright (C) 2008-2009 Karel Zak <kzak@redhat.com>
+ *
+ * This file may be redistributed under the terms of the
+ * GNU Lesser General Public License.
+ */
+
+#include <unistd.h>
+#include <errno.h>
+#include <stdlib.h>
+#include <string.h>
+#ifdef HAVE_SYS_PRCTL_H
+#include <sys/prctl.h>
+#else
+#define PR_GET_DUMPABLE 3
+#endif
+#if (!defined(HAVE_PRCTL) && defined(linux))
+#include <sys/syscall.h>
+#endif
+#include <sys/stat.h>
+#include <ctype.h>
+#include <sys/types.h>
+#include <fcntl.h>
+#include <pwd.h>
+
+#include "mountP.h"
+
+char *mnt_getenv_safe(const char *arg)
+{
+	if ((getuid() != geteuid()) || (getgid() != getegid()))
+		return NULL;
+#if HAVE_PRCTL
+	if (prctl(PR_GET_DUMPABLE, 0, 0, 0, 0) == 0)
+		return NULL;
+#else
+#if (defined(linux) && defined(SYS_prctl))
+	if (syscall(SYS_prctl, PR_GET_DUMPABLE, 0, 0, 0, 0) == 0)
+		return NULL;
+#endif
+#endif
+
+#ifdef HAVE___SECURE_GETENV
+	return __secure_getenv(arg);
+#else
+	return getenv(arg);
+#endif
+}
+
+/* TODO: move strn<...> functions to top-level lib/strn.c */
+#ifndef HAVE_STRNLEN
+size_t strnlen(const char *s, size_t maxlen)
+{
+	int i;
+
+	for (i = 0; i < maxlen; i++) {
+		if (s[i] == '\0')
+			return i + 1;
+	}
+	return maxlen;
+}
+#endif
+
+#ifndef HAVE_STRNCHR
+char *strnchr(const char *s, size_t maxlen, int c)
+{
+	for (; maxlen-- && *s != '\0'; ++s)
+		if (*s == (char)c)
+			return (char *)s;
+	return NULL;
+}
+#endif
+
+#ifndef HAVE_STRNDUP
+char *strndup(const char *s, size_t n)
+{
+  size_t len = strnlen (s, n);
+  char *new = (char *) malloc (len + 1);
+
+  if (new == NULL)
+    return NULL;
+
+  new[len] = '\0';
+  return (char *) memcpy (new, s, len);
+}
+#endif
+
+
+/**
+ * mnt_fstype_is_pseudofs:
+ * @type: filesystem name
+ *
+ * Returns: 1 for filesystems like proc, sysfs, ... or 0.
+ */
+int mnt_fstype_is_pseudofs(const char *type)
+{
+	if (!type)
+		return 0;
+	if (strcmp(type, "none")  == 0 ||
+	    strcmp(type, "proc")  == 0 ||
+	    strcmp(type, "tmpfs") == 0 ||
+	    strcmp(type, "sysfs") == 0 ||
+	    strcmp(type, "devpts") == 0||
+	    strcmp(type, "cgroups") == 0 ||
+	    strcmp(type, "devfs") == 0 ||
+	    strcmp(type, "dlmfs") == 0 ||
+	    strcmp(type, "cpuset") == 0 ||
+	    strcmp(type, "spufs") == 0)
+		return 1;
+	return 0;
+}
+
+/**
+ * mnt_fstype_is_netfs:
+ * @type: filesystem name
+ *
+ * Returns: 1 for filesystems like cifs, nfs, ... or 0.
+ */
+int mnt_fstype_is_netfs(const char *type)
+{
+	if (!type)
+		return 0;
+	if (strcmp(type, "cifs")  == 0 ||
+	    strcmp(type, "smbfs")  == 0 ||
+	    strncmp(type, "nfs", 3) == 0 ||
+	    strcmp(type, "afs") == 0 ||
+	    strcmp(type, "ncpfs") == 0)
+		return 1;
+	return 0;
+}
+
+/*
+ * Reallocates its first arg @s - typical use: s = mnt_strconcat3(s,t,u);
+ * Returns reallocated @s ion succes or NULL in case of error.
+ */
+char *mnt_strconcat3(char *s, const char *t, const char *u)
+{
+     size_t len = 0;
+
+     len = (s ? strlen(s) : 0) + (t ? strlen(t) : 0) + (u ? strlen(u) : 0);
+
+     if (!len)
+	     return NULL;
+     if (!s) {
+	     s = malloc(len + 1);
+	     *s = '\0';
+     } else
+	     s = realloc(s, len + 1);
+
+     if (!s)
+	     return NULL;
+     if (t)
+	     strcat(s, t);
+     if (u)
+	     strcat(s, u);
+     return s;
+}
+
+/**
+ * mnt_open_device:
+ * @devname: device path
+ * @flags: open(2) flags
+ *
+ * Opens device like open(2), but waits for cdrom medium (if errno=ENOMEDIUM).
+ *
+ * Returns: file descriptor or -1 in case of error.
+ */
+int mnt_open_device(const char *devname, int flags)
+{
+	int retries = 0;
+
+	do {
+		int fd = open(devname, flags);
+		if (fd >= 0)
+			return fd;
+		if (errno != ENOMEDIUM)
+			break;
+		if (retries >= CONFIG_CDROM_NOMEDIUM_RETRIES)
+			break;
+		++retries;
+		sleep(3);
+	} while(1);
+
+	return -1;
+}
+
+/*
+ * Returns allocated string with username or NULL.
+ */
+char *mnt_get_username(const uid_t uid)
+{
+        struct passwd pwd;
+	struct passwd *res;
+	size_t sz = sysconf(_SC_GETPW_R_SIZE_MAX);
+	char *buf, *username = NULL;
+
+	if (sz <= 0)
+		sz = 16384;        /* Should be more than enough */
+
+	buf = malloc(sz);
+	if (!buf)
+		return NULL;
+
+	if (!getpwuid_r(uid, &pwd, buf, sz, &res) && res)
+		username = strdup(pwd.pw_name);
+
+	free(buf);
+	return username;
+}