libshare: nfs: commonify nfs_enable_share()

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: George Wilson <gwilson@delphix.com>
Signed-off-by: Ahelenia Ziemiańska <nabijaczleweli@nabijaczleweli.xyz>
Closes #11886

lib/libshare/nfs.c

@@ -38,7 +38,7 @@ static int nfs_lock_fd = -1;
  * updates to the exports file. Each protocol is responsible for
  * providing the necessary locking to ensure consistency.
  */
-__attribute__((visibility("hidden"))) int
+static int
 nfs_exports_lock(const char *name)
 {
 	int err;
@@ -61,7 +61,7 @@ nfs_exports_lock(const char *name)
 	return (0);
 }
 
-__attribute__((visibility("hidden"))) void
+static void
 nfs_exports_unlock(const char *name)
 {
 	verify(nfs_lock_fd > 0);
@@ -75,7 +75,7 @@ nfs_exports_unlock(const char *name)
 	nfs_lock_fd = -1;
 }
 
-__attribute__((visibility("hidden"))) char *
+static char *
 nfs_init_tmpfile(const char *prefix, const char *mdir)
 {
 	char *tmpfile = NULL;
@@ -105,7 +105,7 @@ nfs_init_tmpfile(const char *prefix, const char *mdir)
 	return (tmpfile);
 }
 
-__attribute__((visibility("hidden"))) int
+static int
 nfs_fini_tmpfile(const char *exports, char *tmpfile)
 {
 	if (rename(tmpfile, exports) == -1) {
@@ -120,8 +120,9 @@ nfs_fini_tmpfile(const char *exports, char *tmpfile)
 }
 
 __attribute__((visibility("hidden"))) int
-nfs_disable_share_impl(const char *lockfile, const char *exports,
+nfs_toggle_share(const char *lockfile, const char *exports,
-    const char *expdir, sa_share_impl_t impl_share)
+    const char *expdir, sa_share_impl_t impl_share,
+    int(*cbk)(sa_share_impl_t impl_share, char *filename))
 {
 	int error;
 	char *filename;
@@ -137,14 +138,20 @@ nfs_disable_share_impl(const char *lockfile, const char *exports,
 	}
 
 	error = nfs_copy_entries(filename, impl_share->sa_mountpoint);
-	if (error != SA_OK) {
+	if (error != SA_OK)
-		unlink(filename);
+		goto fullerr;
-		free(filename);
+
-		nfs_exports_unlock(lockfile);
+	error = cbk(impl_share, filename);
-		return (error);
+	if (error != SA_OK)
-	}
+		goto fullerr;
 
 	error = nfs_fini_tmpfile(exports, filename);
 	nfs_exports_unlock(lockfile);
 	return (error);
+
+fullerr:
+	unlink(filename);
+	free(filename);
+	nfs_exports_unlock(lockfile);
+	return (error);
 }

lib/libshare/nfs.h

@@ -30,12 +30,7 @@
 
 void libshare_nfs_init(void);
 
-int nfs_exports_lock(const char *name);
-void nfs_exports_unlock(const char *name);
-
-char *nfs_init_tmpfile(const char *prefix, const char *mdir);
-int nfs_fini_tmpfile(const char *exports, char *tmpfile);
-
 int nfs_copy_entries(char *filename, const char *mountpoint);
-int nfs_disable_share_impl(const char *lockfile, const char *exports,
+int nfs_toggle_share(const char *lockfile, const char *exports,
-    const char *expdir, sa_share_impl_t impl_share);
+    const char *expdir, sa_share_impl_t impl_share,
+    int(*cbk)(sa_share_impl_t impl_share, char *filename));

lib/libshare/os/freebsd/nfs.c

@@ -193,38 +193,15 @@ nfs_copy_entries(char *filename, const char *mountpoint)
 }
 
 static int
-nfs_enable_share(sa_share_impl_t impl_share)
+nfs_enable_share_impl(sa_share_impl_t impl_share, char *filename)
 {
-	char *filename = NULL;
-	int error;
-
-	if ((filename = nfs_init_tmpfile(ZFS_EXPORTS_FILE, NULL)) == NULL)
-		return (SA_SYSTEM_ERR);
-
-	error = nfs_exports_lock(ZFS_EXPORTS_LOCK);
-	if (error != 0) {
-		unlink(filename);
-		free(filename);
-		return (error);
-	}
-
-	error = nfs_copy_entries(filename, impl_share->sa_mountpoint);
-	if (error != SA_OK) {
-		unlink(filename);
-		free(filename);
-		nfs_exports_unlock(ZFS_EXPORTS_LOCK);
-		return (error);
-	}
-
 	FILE *fp = fopen(filename, "a+e");
 	if (fp == NULL) {
 		fprintf(stderr, "failed to open %s file: %s", filename,
 		    strerror(errno));
-		unlink(filename);
-		free(filename);
-		nfs_exports_unlock(ZFS_EXPORTS_LOCK);
 		return (SA_SYSTEM_ERR);
 	}
+
 	char *shareopts = FSINFO(impl_share, nfs_fstype)->shareopts;
 	if (strcmp(shareopts, "on") == 0)
 		shareopts = "";
@@ -233,30 +210,38 @@ nfs_enable_share(sa_share_impl_t impl_share)
 	    translate_opts(shareopts)) < 0) {
 		fprintf(stderr, "failed to write to %s\n", filename);
 		fclose(fp);
-		unlink(filename);
-		free(filename);
-		nfs_exports_unlock(ZFS_EXPORTS_LOCK);
 		return (SA_SYSTEM_ERR);
 	}
 
 	if (fclose(fp) != 0) {
 		fprintf(stderr, "Unable to close file %s: %s\n",
 		    filename, strerror(errno));
-		unlink(filename);
-		free(filename);
-		nfs_exports_unlock(ZFS_EXPORTS_LOCK);
 		return (SA_SYSTEM_ERR);
 	}
-	error = nfs_fini_tmpfile(ZFS_EXPORTS_FILE, filename);
+
-	nfs_exports_unlock(ZFS_EXPORTS_LOCK);
+	return (SA_OK);
-	return (error);
+}
+
+static int
+nfs_enable_share(sa_share_impl_t impl_share)
+{
+	return (nfs_toggle_share(
+	    ZFS_EXPORTS_LOCK, ZFS_EXPORTS_FILE, NULL, impl_share,
+	    nfs_enable_share_impl));
+}
+
+static int
+nfs_disable_share_impl(sa_share_impl_t impl_share, char *filename)
+{
+	return (SA_OK);
 }
 
 static int
 nfs_disable_share(sa_share_impl_t impl_share)
 {
-	return (nfs_disable_share_impl(
+	return (nfs_toggle_share(
-	    ZFS_EXPORTS_LOCK, ZFS_EXPORTS_FILE, NULL, impl_share));
+	    ZFS_EXPORTS_LOCK, ZFS_EXPORTS_FILE, NULL, impl_share,
+	    nfs_disable_share_impl));
 }
 
 static boolean_t

lib/libshare/os/linux/nfs.c

@@ -467,61 +467,45 @@ nfs_copy_entries(char *filename, const char *mountpoint)
  * Enables NFS sharing for the specified share.
  */
 static int
-nfs_enable_share(sa_share_impl_t impl_share)
+nfs_enable_share_impl(sa_share_impl_t impl_share, char *filename)
 {
 	char *shareopts, *linux_opts;
-	char *filename = NULL;
 	int error;
 
-	if ((filename =
-	    nfs_init_tmpfile(ZFS_EXPORTS_FILE, ZFS_EXPORTS_DIR)) == NULL)
-		return (SA_SYSTEM_ERR);
-
-	error = nfs_exports_lock(ZFS_EXPORTS_LOCK);
-	if (error != 0) {
-		unlink(filename);
-		free(filename);
-		return (error);
-	}
-
-	error = nfs_copy_entries(filename, impl_share->sa_mountpoint);
-	if (error != SA_OK) {
-		unlink(filename);
-		free(filename);
-		nfs_exports_unlock(ZFS_EXPORTS_LOCK);
-		return (error);
-	}
-
 	shareopts = FSINFO(impl_share, nfs_fstype)->shareopts;
 	error = get_linux_shareopts(shareopts, &linux_opts);
-	if (error != SA_OK) {
+	if (error != SA_OK)
-		unlink(filename);
-		free(filename);
-		nfs_exports_unlock(ZFS_EXPORTS_LOCK);
 		return (error);
-	}
 
 	error = foreach_nfs_host(impl_share, filename, nfs_add_entry,
 	    linux_opts);
 	free(linux_opts);
-	if (error == 0) {
-		error = nfs_fini_tmpfile(ZFS_EXPORTS_FILE, filename);
-	} else {
-		unlink(filename);
-		free(filename);
-	}
-	nfs_exports_unlock(ZFS_EXPORTS_LOCK);
 	return (error);
 }
 
+static int
+nfs_enable_share(sa_share_impl_t impl_share)
+{
+	return (nfs_toggle_share(
+	    ZFS_EXPORTS_LOCK, ZFS_EXPORTS_FILE, ZFS_EXPORTS_DIR, impl_share,
+	    nfs_enable_share_impl));
+}
+
 /*
  * Disables NFS sharing for the specified share.
  */
+static int
+nfs_disable_share_impl(sa_share_impl_t impl_share, char *filename)
+{
+	return (SA_OK);
+}
+
 static int
 nfs_disable_share(sa_share_impl_t impl_share)
 {
-	return (nfs_disable_share_impl(
+	return (nfs_toggle_share(
-	    ZFS_EXPORTS_LOCK, ZFS_EXPORTS_FILE, ZFS_EXPORTS_DIR, impl_share));
+	    ZFS_EXPORTS_LOCK, ZFS_EXPORTS_FILE, ZFS_EXPORTS_DIR, impl_share,
+	    nfs_disable_share_impl));
 }
 
 static boolean_t