1 files changed, 158 insertions, 0 deletions
diff --git a/systemd/nfs-server-generator.c b/systemd/nfs-server-generator.c
new file mode 100644
index 0000000..eec98fd
--- /dev/null
+++ b/systemd/nfs-server-generator.c
@@ -0,0 +1,158 @@
+/*
+ * nfs-server-generator:
+ *   systemd generator to create ordering dependencies between
+ *   nfs-server and various filesystem mounts
+ *
+ * 1/ nfs-server should start Before any 'nfs' mountpoints are
+ *    mounted, in case they are loop-back mounts.  This ordering is particularly
+ *    important for the shutdown side, so the nfs-server is stopped
+ *    after the filesystems are unmounted.
+ * 2/ nfs-server should start After all exported filesystems are mounted
+ *    so there is no risk of exporting the underlying directory.
+ *    This is particularly important for _net mounts which
+ *    are not caught by "local-fs.target".
+ */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <string.h>
+#include <ctype.h>
+#include <stdio.h>
+#include <mntent.h>
+#include <alloca.h>
+
+#include "misc.h"
+#include "nfslib.h"
+#include "exportfs.h"
+#include "systemd.h"
+
+/* A simple "set of strings" to remove duplicates
+ * found in /etc/exports
+ */
+struct list {
+	struct list *next;
+	char *name;
+};
+static int is_unique(struct list **lp, char *path)
+{
+	struct list *l = *lp;
+
+	while (l) {
+		if (strcmp(l->name, path) == 0)
+			return 0;
+		l = l->next;
+	}
+	l = malloc(sizeof(*l));
+	if (l == NULL)
+		return 0;
+	l->name = path;
+	l->next = *lp;
+	*lp = l;
+	return 1;
+}
+
+static int has_noauto_flag(char *path)
+{
+	FILE		*fstab;
+	struct mntent	*mnt;
+
+	fstab = setmntent("/etc/fstab", "r");
+	if (!fstab)
+		return 0;
+
+	while ((mnt = getmntent(fstab)) != NULL) {
+		int l = strlen(mnt->mnt_dir);
+		if (strncmp(mnt->mnt_dir, path, l) != 0)
+			continue;
+		if (path[l] && path[l] != '/')
+			continue;
+		if (hasmntopt(mnt, "noauto"))
+			break;
+	}
+	fclose(fstab);
+	return mnt != NULL;
+}
+
+int main(int argc, char *argv[])
+{
+	char		*path, *spath;
+	char		dirbase[] = "/nfs-server.service.d";
+	char		filebase[] = "/order-with-mounts.conf";
+	nfs_export	*exp;
+	int		i;
+	struct list	*list = NULL;
+	FILE		*f, *fstab;
+	struct mntent	*mnt;
+
+	/* Avoid using any external services */
+	xlog_syslog(0);
+
+	if (argc != 4 || argv[1][0] != '/') {
+		fprintf(stderr, "nfs-server-generator: create systemd dependencies for nfs-server\n");
+		fprintf(stderr, "Usage: normal-dir early-dir late-dir\n");
+		exit(1);
+	}
+
+	path = alloca(strlen(argv[1]) + sizeof(dirbase) + sizeof(filebase));
+	if (!path)
+		exit(2);
+	if (export_read(_PATH_EXPORTS, 1) +
+	    export_d_read(_PATH_EXPORTS_D, 1) == 0)
+		/* Nothing is exported, so nothing to do */
+		exit(0);
+
+	strcat(strcpy(path, argv[1]), dirbase);
+	mkdir(path, 0755);
+	strcat(path, filebase);
+	f = fopen(path, "w");
+	if (!f)
+		exit(1);
+	fprintf(f, "# Automatically generated by nfs-server-generator\n\n[Unit]\n");
+
+	for (i = 0; i < MCL_MAXTYPES; i++) {
+		for (exp = exportlist[i].p_head; exp; exp = exp->m_next) {
+			if (!is_unique(&list, exp->m_export.e_path))
+				continue;
+			if (exp->m_export.e_mountpoint)
+				continue;
+			if (has_noauto_flag(exp->m_export.e_path))
+				continue;
+			if (strchr(exp->m_export.e_path, ' '))
+				fprintf(f, "RequiresMountsFor=\"%s\"\n",
+					exp->m_export.e_path);
+			else
+				fprintf(f, "RequiresMountsFor=%s\n",
+					exp->m_export.e_path);
+		}
+	}
+
+	fstab = setmntent("/etc/fstab", "r");
+	if (!fstab)
+		exit(1);
+
+	while ((mnt = getmntent(fstab)) != NULL) {
+		if (strcmp(mnt->mnt_type, "nfs") != 0 &&
+		    strcmp(mnt->mnt_type, "nfs4") != 0)
+			continue;
+
+		spath = systemd_escape(mnt->mnt_dir, ".mount");
+		if (!spath) {
+			fprintf(stderr, 
+				"nfs-server-generator: convert path failed: %s\n",
+				mnt->mnt_dir);
+			continue;
+		}
+		fprintf(f, "Before=%s\n", spath);
+	}
+
+	fclose(fstab);
+	fclose(f);
+
+	exit(0);
+}