From 292ce46b60e2c12450c5c21044acf9c41bd837df Mon Sep 17 00:00:00 2001 From: "Shawn O. Pearce" Date: Fri, 30 Oct 2009 17:47:28 -0700 Subject: [PATCH] remote-helpers: Fetch more than one ref in a batch Some network protocols (e.g. native git://) are able to fetch more than one ref at a time and reduce the overall transfer cost by combining the requests into a single exchange. Instead of feeding each fetch request one at a time to the helper, feed all of them at once so the helper can decide whether or not it should batch them. Signed-off-by: Shawn O. Pearce CC: Daniel Barkalow Signed-off-by: Junio C Hamano --- Documentation/git-remote-helpers.txt | 14 ++++-- remote-curl.c | 88 +++++++++++++++++++++++++++++++----- transport-helper.c | 39 +++++++++++----- 3 files changed, 115 insertions(+), 26 deletions(-) diff --git a/Documentation/git-remote-helpers.txt b/Documentation/git-remote-helpers.txt index 173ee232f2..e44d821c7b 100644 --- a/Documentation/git-remote-helpers.txt +++ b/Documentation/git-remote-helpers.txt @@ -36,10 +36,16 @@ Commands are given by the caller on the helper's standard input, one per line. complete list, outputs a blank line. 'fetch' :: - Fetches the given object, writing the necessary objects to the - database. Outputs a blank line when the fetch is - complete. Only objects which were reported in the ref list - with a sha1 may be fetched this way. + Fetches the given object, writing the necessary objects + to the database. Fetch commands are sent in a batch, one + per line, and the batch is terminated with a blank line. + Outputs a single blank line when all fetch commands in the + same batch are complete. Only objects which were reported + in the ref list with a sha1 may be fetched this way. ++ +Optionally may output a 'lock ' line indicating a file under +GIT_DIR/objects/pack which is keeping a pack until refs can be +suitably updated. + Supported if the helper has the "fetch" capability. diff --git a/remote-curl.c b/remote-curl.c index 478f3ea7d3..22cd5c5fd2 100644 --- a/remote-curl.c +++ b/remote-curl.c @@ -87,6 +87,81 @@ static struct ref *get_refs(void) return refs; } +static int fetch_dumb(int nr_heads, struct ref **to_fetch) +{ + char **targets = xmalloc(nr_heads * sizeof(char*)); + int ret, i; + + for (i = 0; i < nr_heads; i++) + targets[i] = xstrdup(sha1_to_hex(to_fetch[i]->old_sha1)); + + init_walker(); + walker->get_all = 1; + walker->get_tree = 1; + walker->get_history = 1; + walker->get_verbosely = 0; + walker->get_recover = 0; + ret = walker_fetch(walker, nr_heads, targets, NULL, NULL); + + for (i = 0; i < nr_heads; i++) + free(targets[i]); + free(targets); + + return ret ? error("Fetch failed.") : 0; +} + +static void parse_fetch(struct strbuf *buf) +{ + struct ref **to_fetch = NULL; + struct ref *list_head = NULL; + struct ref **list = &list_head; + int alloc_heads = 0, nr_heads = 0; + + do { + if (!prefixcmp(buf->buf, "fetch ")) { + char *p = buf->buf + strlen("fetch "); + char *name; + struct ref *ref; + unsigned char old_sha1[20]; + + if (strlen(p) < 40 || get_sha1_hex(p, old_sha1)) + die("protocol error: expected sha/ref, got %s'", p); + if (p[40] == ' ') + name = p + 41; + else if (!p[40]) + name = ""; + else + die("protocol error: expected sha/ref, got %s'", p); + + ref = alloc_ref(name); + hashcpy(ref->old_sha1, old_sha1); + + *list = ref; + list = &ref->next; + + ALLOC_GROW(to_fetch, nr_heads + 1, alloc_heads); + to_fetch[nr_heads++] = ref; + } + else + die("http transport does not support %s", buf->buf); + + strbuf_reset(buf); + if (strbuf_getline(buf, stdin, '\n') == EOF) + return; + if (!*buf->buf) + break; + } while (1); + + if (fetch_dumb(nr_heads, to_fetch)) + exit(128); /* error already reported */ + free_refs(list_head); + free(to_fetch); + + printf("\n"); + fflush(stdout); + strbuf_reset(buf); +} + int main(int argc, const char **argv) { struct strbuf buf = STRBUF_INIT; @@ -110,17 +185,8 @@ int main(int argc, const char **argv) if (strbuf_getline(&buf, stdin, '\n') == EOF) break; if (!prefixcmp(buf.buf, "fetch ")) { - char *obj = buf.buf + strlen("fetch "); - init_walker(); - walker->get_all = 1; - walker->get_tree = 1; - walker->get_history = 1; - walker->get_verbosely = 0; - walker->get_recover = 0; - if (walker_fetch(walker, 1, &obj, NULL, NULL)) - die("Fetch failed."); - printf("\n"); - fflush(stdout); + parse_fetch(&buf); + } else if (!strcmp(buf.buf, "list")) { struct ref *refs = get_refs(); struct ref *posn; diff --git a/transport-helper.c b/transport-helper.c index f57e84c676..9de3408947 100644 --- a/transport-helper.c +++ b/transport-helper.c @@ -10,6 +10,7 @@ struct helper_data { const char *name; struct child_process *helper; + FILE *out; unsigned fetch : 1; }; @@ -18,7 +19,6 @@ static struct child_process *get_helper(struct transport *transport) struct helper_data *data = transport->data; struct strbuf buf = STRBUF_INIT; struct child_process *helper; - FILE *file; if (data->helper) return data->helper; @@ -39,9 +39,9 @@ static struct child_process *get_helper(struct transport *transport) write_str_in_full(helper->in, "capabilities\n"); - file = xfdopen(helper->out, "r"); + data->out = xfdopen(helper->out, "r"); while (1) { - if (strbuf_getline(&buf, file, '\n') == EOF) + if (strbuf_getline(&buf, data->out, '\n') == EOF) exit(128); /* child died, message supplied already */ if (!*buf.buf) @@ -58,6 +58,7 @@ static int disconnect_helper(struct transport *transport) if (data->helper) { write_str_in_full(data->helper->in, "\n"); close(data->helper->in); + fclose(data->out); finish_command(data->helper); free((char *)data->helper->argv[0]); free(data->helper->argv); @@ -70,8 +71,7 @@ static int disconnect_helper(struct transport *transport) static int fetch_with_fetch(struct transport *transport, int nr_heads, const struct ref **to_fetch) { - struct child_process *helper = get_helper(transport); - FILE *file = xfdopen(helper->out, "r"); + struct helper_data *data = transport->data; int i; struct strbuf buf = STRBUF_INIT; @@ -82,12 +82,30 @@ static int fetch_with_fetch(struct transport *transport, strbuf_addf(&buf, "fetch %s %s\n", sha1_to_hex(posn->old_sha1), posn->name); - write_in_full(helper->in, buf.buf, buf.len); - strbuf_reset(&buf); + } - if (strbuf_getline(&buf, file, '\n') == EOF) + strbuf_addch(&buf, '\n'); + if (write_in_full(data->helper->in, buf.buf, buf.len) != buf.len) + die_errno("cannot send fetch to %s", data->name); + + while (1) { + strbuf_reset(&buf); + if (strbuf_getline(&buf, data->out, '\n') == EOF) exit(128); /* child died, message supplied already */ + + if (!prefixcmp(buf.buf, "lock ")) { + const char *name = buf.buf + 5; + if (transport->pack_lockfile) + warning("%s also locked %s", data->name, name); + else + transport->pack_lockfile = xstrdup(name); + } + else if (!buf.len) + break; + else + warning("%s unexpectedly said: '%s'", data->name, buf.buf); } + strbuf_release(&buf); return 0; } @@ -113,21 +131,20 @@ static int fetch(struct transport *transport, static struct ref *get_refs_list(struct transport *transport, int for_push) { + struct helper_data *data = transport->data; struct child_process *helper; struct ref *ret = NULL; struct ref **tail = &ret; struct ref *posn; struct strbuf buf = STRBUF_INIT; - FILE *file; helper = get_helper(transport); write_str_in_full(helper->in, "list\n"); - file = xfdopen(helper->out, "r"); while (1) { char *eov, *eon; - if (strbuf_getline(&buf, file, '\n') == EOF) + if (strbuf_getline(&buf, data->out, '\n') == EOF) exit(128); /* child died, message supplied already */ if (!*buf.buf) -- 2.11.4.GIT