[RFC 07/16] Allow reading svn dumps from files via file:// urls.

[Florian Achleitner <florian.achleitner.2.6.31@gmail.com>]

For testing as well as for importing large, already
available dumps, it's useful to bypass svnrdump and
replay the svndump from a file directly.

Add support for file:// urls in the remote url.
e.g. svn::file:///path/to/dump
When the remote helper finds an url starting with
file:// it tries to open that file instead of invoking svnrdump.

Signed-off-by: Florian Achleitner <florian.achleitner.2.6.31@gmail.com>
---
 contrib/svn-fe/remote-svn.c |   56 +++++++++++++++++++++++++++++--------------
 1 file changed, 38 insertions(+), 18 deletions(-)

diff --git a/contrib/svn-fe/remote-svn.c b/contrib/svn-fe/remote-svn.c
index 29fc371..862b739 100644
--- a/contrib/svn-fe/remote-svn.c
+++ b/contrib/svn-fe/remote-svn.c
@@ -23,6 +23,7 @@ static inline void printd(const char *fmt, ...)
 }
 
 static const char *url;
+static int dump_from_file;
 static const char *private_ref;
 static const char *remote_ref = "refs/heads/master";
 
@@ -105,18 +106,28 @@ enum cmd_result cmd_import(struct strbuf *line)
 	}
 	printd("Opened fast-import back-pipe %s for reading.", back_pipe_env);
 
-	memset(&svndump_proc, 0, sizeof (struct child_process));
-	svndump_proc.out = -1;
-	argv_array_push(&svndump_argv, "svnrdump");
-	argv_array_push(&svndump_argv, "dump");
-	argv_array_push(&svndump_argv, url);
-	argv_array_pushf(&svndump_argv, "-r%u:HEAD", startrev);
-	svndump_proc.argv = svndump_argv.argv;
+	if(dump_from_file) {
+		dumpin_fd = open(url, O_RDONLY);
+		if(dumpin_fd < 0) {
+			die_errno("Couldn't open svn dump file %s.", url);
+		}
+	}
+	else {
+		memset(&svndump_proc, 0, sizeof (struct child_process));
+		svndump_proc.out = -1;
+		argv_array_push(&svndump_argv, "svnrdump");
+		argv_array_push(&svndump_argv, "dump");
+		argv_array_push(&svndump_argv, url);
+		argv_array_pushf(&svndump_argv, "-r%u:HEAD", startrev);
+		svndump_proc.argv = svndump_argv.argv;
+
+		code = start_command(&svndump_proc);
+		if (code)
+			die("Unable to start %s, code %d", svndump_proc.argv[0], code);
+		dumpin_fd = svndump_proc.out;
+
+	}
 
-	code = start_command(&svndump_proc);
-	if (code)
-		die("Unable to start %s, code %d", svndump_proc.argv[0], code);
-	dumpin_fd = svndump_proc.out;
 
 	svndump_init_fd(dumpin_fd, report_fd);
 	svndump_read(url, private_ref);
@@ -125,10 +136,12 @@ enum cmd_result cmd_import(struct strbuf *line)
 
 	close(dumpin_fd);
 	close(report_fd);
-	code = finish_command(&svndump_proc);
-	if (code)
-		warning("%s, returned %d", svndump_proc.argv[0], code);
-	argv_array_clear(&svndump_argv);
+	if(!dump_from_file) {
+		code = finish_command(&svndump_proc);
+		if (code)
+			warning("%s, returned %d", svndump_proc.argv[0], code);
+		argv_array_clear(&svndump_argv);
+	}
 
 	return SUCCESS;
 }
@@ -191,9 +204,16 @@ int main(int argc, const char **argv)
 	else
 		warning("Excess arguments!");
 
-	end_url_with_slash(&buf, url);
-	url = strbuf_detach(&buf, NULL);
-
+	if (!prefixcmp(url, "file://")) {
+		dump_from_file = 1;
+		url = url_decode(url + sizeof("file://")-1);
+		printd("remote-svn uses a file as dump input.");
+	}
+	else {
+		dump_from_file = 0;
+		end_url_with_slash(&buf, url);
+		url = strbuf_detach(&buf, NULL);
+	}
 	printd("remote-svn starting with url %s", url);
 
 	strbuf_init(&buf, 0);
-- 
1.7.9.5