Refactor, replace deprecated setfsent() & C:o with setmntent()

The setfsent() family of APIs was never standardized and on Linux only
GLIBC implement them.  We've tried to overcome this limitation, and to
support uClibc/uClibc-ng and musl libc, by providing replacements APIs
in helpers.c.

However, and since we want to support alternative /etc/fstab files, the
setmntent() family of APIs is more widespread and supports reading from
any fstab or mtab file.

Signed-off-by: Joachim Wiberg <troglobit@gmail.com>

configure.ac

@@ -33,8 +33,8 @@ AC_PROG_MKDIR_P
 
 # Configuration.
 AC_HEADER_STDC
-AC_CHECK_HEADERS([fstab.h termios.h sys/ioctl.h])
+AC_CHECK_HEADERS([termios.h sys/ioctl.h mntent.h])
-AC_CHECK_FUNCS([strstr getopt getfsenty])
+AC_CHECK_FUNCS([strstr getopt getmntent])
 
 # Check for uint[8,16,32]_t
 AC_TYPE_UINT8_T

src/finit.c

@@ -26,11 +26,10 @@
 
 #include <ctype.h>
 #include <dirent.h>
-#ifdef HAVE_FSTAB_H
-#include <fstab.h>
-#endif
 #include <getopt.h>
+#ifdef HAVE_MNTENT_H
 #include <mntent.h>
+#endif
 #include <time.h>		/* tzet() */
 #include <sys/klog.h>
 #include <sys/mount.h>
@@ -111,41 +110,43 @@ static void banner(void)
  */
 static int fsck(int pass)
 {
-	struct fstab *fs;
+	struct mntent *mnt;
 	int rc = 0;
+	FILE *fp;
 
-	if (!setfsent()) {
+	fp = setmntent("/etc/fstab", "r");
+	if (!fp) {
 		_pe("Failed opening fstab");
 		return 1;
 	}
 
-	while ((fs = getfsent())) {
+	while ((mnt = getmntent(fp))) {
 		char cmd[80];
 		struct stat st;
 		int fsck_rc = 0;
 
-		if (fs->fs_passno != pass)
+		if (mnt->mnt_passno != pass)
 			continue;
 
 		errno = 0;
-		if (stat(fs->fs_spec, &st) || !S_ISBLK(st.st_mode)) {
+		if (stat(mnt->mnt_fsname, &st) || !S_ISBLK(st.st_mode)) {
-			if (!string_match(fs->fs_spec, "UUID=") && !string_match(fs->fs_spec, "LABEL=")) {
+			if (!string_match(mnt->mnt_fsname, "UUID=") && !string_match(mnt->mnt_fsname, "LABEL=")) {
-				_d("Cannot fsck %s, not a block device: %s", fs->fs_spec, strerror(errno));
+				_d("Cannot fsck %s, not a block device: %s", mnt->mnt_fsname, strerror(errno));
 				continue;
 			}
 		}
 
-		if (ismnt("/proc/mounts", fs->fs_file, "rw")) {
+		if (ismnt("/proc/mounts", mnt->mnt_dir, "rw")) {
-			_d("Skipping fsck of %s, already mounted rw on %s.", fs->fs_spec, fs->fs_file);
+			_d("Skipping fsck of %s, already mounted rw on %s.", mnt->mnt_fsname, mnt->mnt_dir);
 			continue;
 		}
 
 #ifdef FSCK_FIX
-		snprintf(cmd, sizeof(cmd), "fsck -yf %s", fs->fs_spec);
+		snprintf(cmd, sizeof(cmd), "fsck -yf %s", mnt->mnt_fsname);
 #else
-		snprintf(cmd, sizeof(cmd), "fsck -a %s", fs->fs_spec);
+		snprintf(cmd, sizeof(cmd), "fsck -a %s", mnt->mnt_fsname);
 #endif
-		fsck_rc = run_interactive(cmd, "Checking filesystem %.13s", fs->fs_spec);
+		fsck_rc = run_interactive(cmd, "Checking filesystem %.13s", mnt->mnt_fsname);
 		/*
 		 * "failure" is defined as exiting with a return code of
 		 * 2 or larger.  A return code of 1 indicates that filesystem
@@ -169,7 +170,7 @@ static int fsck(int pass)
 		rc += fsck_rc;
 	}
 
-	endfsent();
+	endmntent(fp);
 
 	return rc;
 }
@@ -202,38 +203,22 @@ static void fs_mount(const char *src, const char *tgt, const char *fstype,
 }
 
 #ifndef SYSROOT
-/* If / is not listed in fstab, or listed as 'ro', leave it alone */
-static int fs_readonly_root(struct fstab *fs)
-{
-	char *tok, *str;
-
-	if (!fs)
-		return 1;
-
-	str = fs->fs_mntops;
-	while ((tok = strtok(str, ","))) {
-		if (!strcmp(tok, "ro"))
-			return 1;
-
-		str = NULL;
-	}
-
-	return 0;
-}
-
 static void fs_remount_root(int fsckerr)
 {
-	struct fstab *fs;
+	struct mntent *mnt;
+	FILE *fp;
 
-	if (!setfsent())
+	fp = setmntent("/etc/fstab", "r");
+	if (!fp)
 		return;
 
-	while ((fs = getfsent())) {
+	while ((mnt = getmntent(fp))) {
-		if (!strcmp(fs->fs_file, "/"))
+		if (strcmp(mnt->mnt_dir, "/"))
-			break;
+			continue;
 	}
 
-	if (fs_readonly_root(fs))
+	/* If / is not listed in fstab, or listed as 'ro', leave it alone */
+	if (!mnt || hasmntopt(mnt, "ro"))
 		goto out;
 
 	if (fsckerr)
@@ -243,7 +228,7 @@ static void fs_remount_root(int fsckerr)
 				"Remounting / as read-write");
 
 out:
-	endfsent();
+	endmntent(fp);
 }
 #else
 static void fs_remount_root(int fsckerr)

src/helpers.c

@@ -587,48 +587,6 @@ int in_container(void)
 	return 0;
 }
 
-#ifndef HAVE_GETFSENT
-static lfile_t *fstab = NULL;
-
-int setfsent(void)
-{
-	if (fstab)
-		lfclose(fstab);
-
-	fstab = lfopen("/etc/fstab", " \t\n");
-	if (!fstab)
-		return 0;
-
-	return 1;
-}
-
-struct fstab *getfsent(void)
-{
-	static struct fstab fs;
-
-	fs.fs_spec    = lftok(fstab);
-	if (fs.fs_spec == NULL)
-		return NULL;
-
-	fs.fs_file    = lftok(fstab);
-	fs.fs_vfstype = lftok(fstab);
-	fs.fs_mntops  = lftok(fstab);
-	fs.fs_type    = "rw";
-	fs.fs_freq    = atoi(lftok(fstab) ?: "0");
-	fs.fs_passno  = atoi(lftok(fstab) ?: "0");
-
-	return &fs;
-}
-
-void endfsent(void)
-{
-	if (fstab)
-		lfclose(fstab);
-
-	fstab = NULL;
-}
-#endif	/* HAVE_GETFSENT */
-
 /**
  * Local Variables:
  *  indent-tabs-mode: t

src/helpers.h

@@ -27,9 +27,6 @@
 
 #include "config.h"
 
-#ifdef HAVE_FSTAB_H
-#include <fstab.h>
-#endif
 #include <mntent.h>
 #include <sched.h>		/* sched_yield() */
 #include <stdarg.h>
@@ -52,22 +49,6 @@ typedef enum {
 	PROGRESS_MODERN,
 } pstyle_t;
 
-#ifndef HAVE_FSTAB_H
-struct fstab {
-	char       *fs_spec;       /* block device name */
-	char       *fs_file;       /* mount point */
-	char       *fs_vfstype;    /* file-system type */
-	char       *fs_mntops;     /* mount options */
-	const char *fs_type;       /* rw/rq/ro/sw/xx option */
-	int         fs_freq;       /* dump frequency, in days */
-	int         fs_passno;     /* pass number on parallel dump */
-};
-
-int           setfsent  (void);
-void          endfsent  (void);
-struct fstab *getfsent  (void);
-#endif /* HAVE_FSTAB_H */
-
 char   *console         (void);
 void    console_init    (void);
 ssize_t cprintf         (const char *fmt, ...) __attribute__ ((format (printf, 1, 2)));

src/mount.c

@@ -23,7 +23,9 @@
 
 #include <errno.h>
 #include <string.h>
+#ifdef HAVE_MNTENT_H
 #include <mntent.h>
+#endif
 #include <sys/mount.h>
 
 #include "helpers.h"