Permalink
Browse files

Discover refs via smart HTTP server when available

Instead of loading the cached info/refs, try to use the smart HTTP
version when the server supports it.  Since the smart variant is
actually the pkt-line stream from the start of either upload-pack
or receive-pack we need to parse these through get_remote_heads,
which requires a background thread to feed its pipe.

Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
CC: Daniel Barkalow <barkalow@iabervon.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
  • Loading branch information...
1 parent f5ba2d1 commit 97cc7bc45c2e076184b84749952b216036a6ecd6 @spearce spearce committed with gitster Oct 31, 2009
Showing with 131 additions and 17 deletions.
  1. +131 −17 remote-curl.c
View
@@ -5,6 +5,7 @@
#include "http.h"
#include "exec_cmd.h"
#include "run-command.h"
+#include "pkt-line.h"
static struct remote *remote;
static const char *url;
@@ -75,21 +76,46 @@ static int set_option(const char *name, const char *value)
}
}
-static struct ref *get_refs(void)
+struct discovery {
+ const char *service;
+ char *buf_alloc;
+ char *buf;
+ size_t len;
+ unsigned proto_git : 1;
+};
+static struct discovery *last_discovery;
+
+static void free_discovery(struct discovery *d)
+{
+ if (d) {
+ if (d == last_discovery)
+ last_discovery = NULL;
+ free(d->buf_alloc);
+ free(d);
+ }
+}
+
+static struct discovery* discover_refs(const char *service)
{
struct strbuf buffer = STRBUF_INIT;
- char *data, *start, *mid;
- char *ref_name;
+ struct discovery *last = last_discovery;
char *refs_url;
- int i = 0;
- int http_ret;
+ int http_ret, is_http = 0;
- struct ref *refs = NULL;
- struct ref *ref = NULL;
- struct ref *last_ref = NULL;
+ if (last && !strcmp(service, last->service))
+ return last;
+ free_discovery(last);
- refs_url = xmalloc(strlen(url) + 11);
- sprintf(refs_url, "%s/info/refs", url);
+ strbuf_addf(&buffer, "%s/info/refs", url);
+ if (!prefixcmp(url, "http://") || !prefixcmp(url, "https://")) {
+ is_http = 1;
+ if (!strchr(url, '?'))
+ strbuf_addch(&buffer, '?');
+ else
+ strbuf_addch(&buffer, '&');
+ strbuf_addf(&buffer, "service=%s", service);
+ }
+ refs_url = strbuf_detach(&buffer, NULL);
init_walker();
http_ret = http_get_strbuf(refs_url, &buffer, HTTP_NO_CACHE);
@@ -104,10 +130,86 @@ static struct ref *get_refs(void)
die("HTTP request failed");
}
- data = buffer.buf;
+ last= xcalloc(1, sizeof(*last_discovery));
+ last->service = service;
+ last->buf_alloc = strbuf_detach(&buffer, &last->len);
+ last->buf = last->buf_alloc;
+
+ if (is_http && 5 <= last->len && last->buf[4] == '#') {
+ /* smart HTTP response; validate that the service
+ * pkt-line matches our request.
+ */
+ struct strbuf exp = STRBUF_INIT;
+
+ if (packet_get_line(&buffer, &last->buf, &last->len) <= 0)
+ die("%s has invalid packet header", refs_url);
+ if (buffer.len && buffer.buf[buffer.len - 1] == '\n')
+ strbuf_setlen(&buffer, buffer.len - 1);
+
+ strbuf_addf(&exp, "# service=%s", service);
+ if (strbuf_cmp(&exp, &buffer))
+ die("invalid server response; got '%s'", buffer.buf);
+ strbuf_release(&exp);
+
+ /* The header can include additional metadata lines, up
+ * until a packet flush marker. Ignore these now, but
+ * in the future we might start to scan them.
+ */
+ strbuf_reset(&buffer);
+ while (packet_get_line(&buffer, &last->buf, &last->len) > 0)
+ strbuf_reset(&buffer);
+
+ last->proto_git = 1;
+ }
+
+ free(refs_url);
+ strbuf_release(&buffer);
+ last_discovery = last;
+ return last;
+}
+
+static int write_discovery(int fd, void *data)
+{
+ struct discovery *heads = data;
+ int err = 0;
+ if (write_in_full(fd, heads->buf, heads->len) != heads->len)
+ err = 1;
+ close(fd);
+ return err;
+}
+
+static struct ref *parse_git_refs(struct discovery *heads)
+{
+ struct ref *list = NULL;
+ struct async async;
+
+ memset(&async, 0, sizeof(async));
+ async.proc = write_discovery;
+ async.data = heads;
+
+ if (start_async(&async))
+ die("cannot start thread to parse advertised refs");
+ get_remote_heads(async.out, &list, 0, NULL, 0, NULL);
+ close(async.out);
+ if (finish_async(&async))
+ die("ref parsing thread failed");
+ return list;
+}
+
+static struct ref *parse_info_refs(struct discovery *heads)
+{
+ char *data, *start, *mid;
+ char *ref_name;
+ int i = 0;
+
+ struct ref *refs = NULL;
+ struct ref *ref = NULL;
+ struct ref *last_ref = NULL;
+
+ data = heads->buf;
start = NULL;
mid = data;
- while (i < buffer.len) {
+ while (i < heads->len) {
if (!start) {
start = &data[i];
}
@@ -131,8 +233,7 @@ static struct ref *get_refs(void)
i++;
}
- strbuf_release(&buffer);
-
+ init_walker();
ref = alloc_ref("HEAD");
if (!walker->fetch_ref(walker, ref) &&
!resolve_remote_symref(ref, refs)) {
@@ -142,11 +243,23 @@ static struct ref *get_refs(void)
free(ref);
}
- strbuf_release(&buffer);
- free(refs_url);
return refs;
}
+static struct ref *get_refs(int for_push)
+{
+ struct discovery *heads;
+
+ if (for_push)
+ heads = discover_refs("git-receive-pack");
+ else
+ heads = discover_refs("git-upload-pack");
+
+ if (heads->proto_git)
+ return parse_git_refs(heads);
+ return parse_info_refs(heads);
+}
+
static void output_refs(struct ref *refs)
{
struct ref *posn;
@@ -317,7 +430,8 @@ int main(int argc, const char **argv)
parse_fetch(&buf);
} else if (!strcmp(buf.buf, "list") || !prefixcmp(buf.buf, "list ")) {
- output_refs(get_refs());
+ int for_push = !!strstr(buf.buf + 4, "for-push");
+ output_refs(get_refs(for_push));
} else if (!prefixcmp(buf.buf, "push ")) {
parse_push(&buf);

0 comments on commit 97cc7bc

Please sign in to comment.