From 97cc7bc45c2e076184b84749952b216036a6ecd6 Mon Sep 17 00:00:00 2001 From: "Shawn O. Pearce" Date: Fri, 30 Oct 2009 17:47:40 -0700 Subject: [PATCH] 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 CC: Daniel Barkalow Signed-off-by: Junio C Hamano --- remote-curl.c | 148 ++++++++++++++++++++++++++++++++++++++++++++------ 1 file changed, 131 insertions(+), 17 deletions(-) diff --git a/remote-curl.c b/remote-curl.c index 5c9dd97d1..3917d45de 100644 --- a/remote-curl.c +++ b/remote-curl.c @@ -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); -- 2.26.2