vcs-svn: Check for errors from open()

test-svn-fe segfaults when passed a bogus path.  Simplify debugging by
exiting with a meaningful error message instead.

Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

contrib/svn-fe/svn-fe.c

@@ -8,7 +8,8 @@
 
 int main(int argc, char **argv)
 {
-	svndump_init(NULL);
+	if (svndump_init(NULL))
+		return 1;
 	svndump_read((argc > 1) ? argv[1] : NULL);
 	svndump_deinit();
 	svndump_reset();

test-svn-fe.c

@@ -9,7 +9,8 @@ int main(int argc, char *argv[])
 {
 	if (argc != 2)
 		usage("test-svn-fe <file>");
-	svndump_init(argv[1]);
+	if (svndump_init(argv[1]))
+		return 1;
 	svndump_read(NULL);
 	svndump_deinit();
 	svndump_reset();

vcs-svn/svndump.c

@@ -290,14 +290,16 @@ void svndump_read(const char *url)
 		handle_revision();
 }
 
-void svndump_init(const char *filename)
+int svndump_init(const char *filename)
 {
-	buffer_init(filename);
+	if (buffer_init(filename))
+		return error("cannot open %s: %s", filename, strerror(errno));
 	repo_init();
 	reset_dump_ctx(~0);
 	reset_rev_ctx(0);
 	reset_node_ctx(NULL);
 	init_keys();
+	return 0;
 }
 
 void svndump_deinit(void)

vcs-svn/svndump.h

@@ -1,7 +1,7 @@
 #ifndef SVNDUMP_H_
 #define SVNDUMP_H_
 
-void svndump_init(const char *filename);
+int svndump_init(const char *filename);
 void svndump_read(const char *url);
 void svndump_deinit(void);
 void svndump_reset(void);