fuse: reorganize mounting code

Macro-driven conditional compilation was a chaos.

New scheme is:

contrib/fuse-lib/mount-common.c:
  libfuse routines used both by glusterfs and fusermount
contrib/fuse-lib/mount.c:
  libfuse-derived but customized mounting code for glusterfs
contrib/fuse-util/mount_util.c:
  libfuse routines used only by fusermount

Change-Id: I3e0ba7f74e36556b78244cd7676eb4d379939602
BUG: 762389
Signed-off-by: Csaba Henk <csaba@redhat.com>
Reviewed-on: http://review.gluster.com/3342
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Anand Avati <avati@redhat.com>

3 files changed, 67 insertions, 21 deletions

diff --git a/contrib/fuse-util/Makefile.am b/contrib/fuse-util/Makefile.am
index a72e3832b..6e9b31c77 100644
--- a/contrib/fuse-util/Makefile.am
+++ b/contrib/fuse-util/Makefile.am
@@ -1,9 +1,9 @@
 bin_PROGRAMS = fusermount-glusterfs
 
-fusermount_glusterfs_SOURCES = fusermount.c $(CONTRIBDIR)/fuse-lib/mount.c
-noinst_HEADERS = mount_util.h
+fusermount_glusterfs_SOURCES = fusermount.c mount_util.c $(CONTRIBDIR)/fuse-lib/mount-common.c
+noinst_HEADERS = $(CONTRIBDIR)/fuse-include/mount_util.h
 
-AM_CFLAGS = -Wall -D_FILE_OFFSET_BITS=64 -DFUSE_UTIL $(GF_CFLAGS) -D_GNU_SOURCE
+AM_CFLAGS = -Wall -D_FILE_OFFSET_BITS=64 -DFUSE_UTIL $(GF_CFLAGS) -D_GNU_SOURCE -I$(CONTRIBDIR)/fuse-include
 
 install-exec-hook:
 	-chown root $(DESTDIR)$(bindir)/fusermount-glusterfs
diff --git a/contrib/fuse-util/mount_util.c b/contrib/fuse-util/mount_util.c
new file mode 100644
index 000000000..911b84445
--- /dev/null
+++ b/contrib/fuse-util/mount_util.c
@@ -0,0 +1,64 @@
+/*
+  FUSE: Filesystem in Userspace
+  Copyright (C) 2001-2007  Miklos Szeredi <miklos@szeredi.hu>
+
+  This program can be distributed under the terms of the GNU LGPLv2.
+  See the file COPYING.LIB.
+*/
+
+#include <dirent.h>
+#include <stdio.h>
+#include <string.h>
+#include <errno.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+
+int fuse_mnt_check_empty(const char *progname, const char *mnt,
+			 mode_t rootmode, off_t rootsize)
+{
+	int isempty = 1;
+
+	if (S_ISDIR(rootmode)) {
+		struct dirent *ent;
+		DIR *dp = opendir(mnt);
+		if (dp == NULL) {
+			fprintf(stderr,
+				"%s: failed to open mountpoint for reading: %s\n",
+				progname, strerror(errno));
+			return -1;
+		}
+		while ((ent = readdir(dp)) != NULL) {
+			if (strcmp(ent->d_name, ".") != 0 &&
+			    strcmp(ent->d_name, "..") != 0) {
+				isempty = 0;
+				break;
+			}
+		}
+		closedir(dp);
+	} else if (rootsize)
+		isempty = 0;
+
+	if (!isempty) {
+		fprintf(stderr, "%s: mountpoint is not empty\n", progname);
+		fprintf(stderr, "%s: if you are sure this is safe, use the 'nonempty' mount option\n", progname);
+		return -1;
+	}
+	return 0;
+}
+
+int fuse_mnt_check_fuseblk(void)
+{
+	char buf[256];
+	FILE *f = fopen("/proc/filesystems", "r");
+	if (!f)
+		return 1;
+
+	while (fgets(buf, sizeof(buf), f))
+		if (strstr(buf, "fuseblk\n")) {
+			fclose(f);
+			return 1;
+		}
+
+	fclose(f);
+	return 0;
+}
diff --git a/contrib/fuse-util/mount_util.h b/contrib/fuse-util/mount_util.h
deleted file mode 100644
index f392f99f1..000000000
--- a/contrib/fuse-util/mount_util.h
+++ /dev/null
@@ -1,18 +0,0 @@
-/*
-  FUSE: Filesystem in Userspace
-  Copyright (C) 2001-2007  Miklos Szeredi <miklos@szeredi.hu>
-
-  This program can be distributed under the terms of the GNU LGPLv2.
-  See the file COPYING.LIB.
-*/
-
-#include <sys/types.h>
-
-int fuse_mnt_add_mount(const char *progname, const char *fsname,
-		       const char *mnt, const char *type, const char *opts);
-int fuse_mnt_umount(const char *progname, const char *abs_mnt,
-		    const char *rel_mnt, int lazy);
-char *fuse_mnt_resolve_path(const char *progname, const char *orig);
-int fuse_mnt_check_empty(const char *progname, const char *mnt,
-			 mode_t rootmode, off_t rootsize);
-int fuse_mnt_check_fuseblk(void);