exportd: Enabled junction support

Moved the junction support from mountd to libexport.a
so both exportd and mountd can use the code.

Signed-off-by: Steve Dickson <steved@redhat.com>

2 files changed, 204 insertions, 1 deletions

diff --git a/support/export/Makefile.am b/support/export/Makefile.am
index 7de82a8..a9e710c 100644
--- a/support/export/Makefile.am
+++ b/support/export/Makefile.am
@@ -12,7 +12,7 @@ EXTRA_DIST	= mount.x
 noinst_LIBRARIES = libexport.a
 libexport_a_SOURCES = client.c export.c hostname.c \
 		      xtab.c mount_clnt.c mount_xdr.c \
-			  cache.c auth.c v4root.c
+			  cache.c auth.c v4root.c fsloc.c
 BUILT_SOURCES 	= $(GENFILES)
 
 noinst_HEADERS = mount.h
diff --git a/support/export/fsloc.c b/support/export/fsloc.c
new file mode 100644
index 0000000..1b869b6
--- /dev/null
+++ b/support/export/fsloc.c
@@ -0,0 +1,203 @@
+/*
+ * COPYRIGHT (c) 2006
+ * THE REGENTS OF THE UNIVERSITY OF MICHIGAN
+ * ALL RIGHTS RESERVED
+ *
+ * Permission is granted to use, copy, create derivative works
+ * and redistribute this software and such derivative works
+ * for any purpose, so long as the name of The University of
+ * Michigan is not used in any advertising or publicity
+ * pertaining to the use of distribution of this software
+ * without specific, written prior authorization.  If the
+ * above copyright notice or any other identification of the
+ * University of Michigan is included in any copy of any
+ * portion of this software, then the disclaimer below must
+ * also be included.
+ *
+ * THIS SOFTWARE IS PROVIDED AS IS, WITHOUT REPRESENTATION
+ * FROM THE UNIVERSITY OF MICHIGAN AS TO ITS FITNESS FOR ANY
+ * PURPOSE, AND WITHOUT WARRANTY BY THE UNIVERSITY OF
+ * MICHIGAN OF ANY KIND, EITHER EXPRESS OR IMPLIED, INCLUDING
+ * WITHOUT LIMITATION THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE
+ * REGENTS OF THE UNIVERSITY OF MICHIGAN SHALL NOT BE LIABLE
+ * FOR ANY DAMAGES, INCLUDING SPECIAL, INDIRECT, INCIDENTAL, OR
+ * CONSEQUENTIAL DAMAGES, WITH RESPECT TO ANY CLAIM ARISING
+ * OUT OF OR IN CONNECTION WITH THE USE OF THE SOFTWARE, EVEN
+ * IF IT HAS BEEN OR IS HEREAFTER ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGES.
+ */
+
+#include <stdlib.h>
+#include <string.h>
+#include <syslog.h>
+
+#include "fsloc.h"
+#include "exportfs.h"
+
+/* Debugging tool: prints out @servers info to syslog */
+static void replicas_print(struct servers *sp)
+{
+	int i;
+	if (!sp) {
+		xlog(L_NOTICE, "NULL replicas pointer");
+		return;
+	}
+	xlog(L_NOTICE, "replicas listsize=%i", sp->h_num);
+	for (i=0; i<sp->h_num; i++) {
+		xlog(L_NOTICE, "    %s:%s",
+		       sp->h_mp[i]->h_host, sp->h_mp[i]->h_path);
+	}
+}
+
+#ifdef DEBUG
+/* Called by setting 'Method = stub' in config file.  Just returns
+ * some syntactically correct gibberish for testing purposes.
+ */
+static struct servers *method_stub(char *key)
+{
+	struct servers *sp;
+	struct mount_point *mp;
+
+	xlog(L_NOTICE, "called method_stub\n");
+	sp = malloc(sizeof(struct servers));
+	if (!sp)
+		return NULL;
+	mp = calloc(1, sizeof(struct mount_point));
+	if (!mp) {
+		free(sp);
+		return NULL;
+	}
+	sp->h_num = 1;
+	sp->h_mp[0] = mp;
+	mp->h_host = strdup("stub_server");
+	mp->h_path = strdup("/my/test/path");
+	sp->h_referral = 1;
+	return sp;
+}
+#endif	/* DEBUG */
+
+/* Scan @list, which is a NULL-terminated array of strings of the
+ * form path@host[+host], and return corresponding servers structure.
+ */
+static struct servers *parse_list(char **list)
+{
+	int i;
+	struct servers *res;
+	struct mount_point *mp;
+	char *cp;
+
+	res = malloc(sizeof(struct servers));
+	if (!res)
+		return NULL;
+	res->h_num = 0;
+
+	/* parse each of the answers in sucession. */
+	for (i=0; list[i] && i<FSLOC_MAX_LIST; i++) {
+		mp = calloc(1, sizeof(struct mount_point));
+		if (!mp) {
+			release_replicas(res);
+			return NULL;
+		}
+		cp = strchr(list[i], '@');
+		if ((!cp) || list[i][0] != '/') {
+			xlog(L_WARNING, "invalid entry '%s'", list[i]);
+			free(mp);
+			continue; /* XXX Need better error handling */
+		}
+		res->h_mp[i] = mp;
+		res->h_num++;
+		mp->h_path = strndup(list[i], cp - list[i]);
+		cp++;
+		mp->h_host = strdup(cp);
+		/* hosts are '+' separated, kernel expects ':' separated */
+		while ( (cp = strchr(mp->h_host, '+')) )
+		       *cp = ':';
+	}
+	return res;
+}
+
+/* @data is a string of form path@host[+host][:path@host[+host]]
+ */
+static struct servers *method_list(char *data)
+{
+	char *copy, *ptr=data, *p;
+	char **list;
+	int i, listsize;
+	struct servers *rv=NULL;
+	bool v6esc = false;
+
+	xlog(L_NOTICE, "method_list(%s)", data);
+	for (ptr--, listsize=1; ptr; ptr=strchr(ptr, ':'), listsize++)
+		ptr++;
+	list = malloc(listsize * sizeof(char *));
+	copy = strdup(data);
+	if (copy)
+		xlog(L_NOTICE, "converted to %s", copy);
+	if (list && copy) {
+		ptr = copy;
+		for (p = ptr, i = 0; *p && i < listsize; p++) {
+			if (*p == '[')
+				v6esc = true;
+			else if (*p == ']')
+				v6esc = false;
+
+			if (!v6esc && *p == ':') {
+				*p = '\0';
+				if (*ptr)
+					list[i++] = ptr;
+				ptr = p + 1;
+			}
+		}
+		if (*ptr)
+			list[i++] = ptr;
+		list[i] = NULL;
+		rv = parse_list(list);
+	}
+	free(copy);
+	free(list);
+	replicas_print(rv);
+	return rv;
+}
+
+/* Returns appropriately filled struct servers, or NULL if had a problem */
+struct servers *replicas_lookup(int method, char *data)
+{
+	struct servers *sp=NULL;
+	switch(method) {
+	case FSLOC_NONE:
+		break;
+	case FSLOC_REFER:
+		sp = method_list(data);
+		if (sp)
+			sp->h_referral = 1;
+		break;
+	case FSLOC_REPLICA:
+		sp = method_list(data);
+		if (sp)
+			sp->h_referral = 0;
+		break;
+#ifdef DEBUG
+	case FSLOC_STUB:
+		sp = method_stub(data);
+		break;
+#endif
+	default:
+		xlog(L_WARNING, "Unknown method = %i", method);
+	}
+	replicas_print(sp);
+	return sp;
+}
+
+void release_replicas(struct servers *server)
+{
+	int i;
+
+	if (!server) return;
+	for (i = 0; i < server->h_num; i++) {
+		free(server->h_mp[i]->h_host);
+		free(server->h_mp[i]->h_path);
+		free(server->h_mp[i]);
+	}
+	free(server);
+}