Merge branch 'ma/http-walker-no-partial'
[git/git.git] / remote-curl.c
index a7c4c9b..ceb0534 100644 (file)
@@ -1,10 +1,11 @@
 #include "cache.h"
 #include "config.h"
 #include "remote.h"
+#include "connect.h"
 #include "strbuf.h"
 #include "walker.h"
 #include "http.h"
-#include "exec_cmd.h"
+#include "exec-cmd.h"
 #include "run-command.h"
 #include "pkt-line.h"
 #include "string-list.h"
@@ -13,6 +14,7 @@
 #include "credential.h"
 #include "sha1-array.h"
 #include "send-pack.h"
+#include "protocol.h"
 #include "quote.h"
 
 static struct remote *remote;
@@ -184,12 +186,13 @@ static int set_option(const char *name, const char *value)
 }
 
 struct discovery {
-       const char *service;
+       char *service;
        char *buf_alloc;
        char *buf;
        size_t len;
        struct ref *refs;
        struct oid_array shallow;
+       enum protocol_version version;
        unsigned proto_git : 1;
 };
 static struct discovery *last_discovery;
@@ -197,8 +200,31 @@ static struct discovery *last_discovery;
 static struct ref *parse_git_refs(struct discovery *heads, int for_push)
 {
        struct ref *list = NULL;
-       get_remote_heads(-1, heads->buf, heads->len, &list,
-                        for_push ? REF_NORMAL : 0, NULL, &heads->shallow);
+       struct packet_reader reader;
+
+       packet_reader_init(&reader, -1, heads->buf, heads->len,
+                          PACKET_READ_CHOMP_NEWLINE |
+                          PACKET_READ_GENTLE_ON_EOF);
+
+       heads->version = discover_version(&reader);
+       switch (heads->version) {
+       case protocol_v2:
+               /*
+                * Do nothing.  This isn't a list of refs but rather a
+                * capability advertisement.  Client would have run
+                * 'stateless-connect' so we'll dump this capability listing
+                * and let them request the refs themselves.
+                */
+               break;
+       case protocol_v1:
+       case protocol_v0:
+               get_remote_heads(&reader, &list, for_push ? REF_NORMAL : 0,
+                                NULL, &heads->shallow);
+               break;
+       case protocol_unknown_version:
+               BUG("unknown protocol version");
+       }
+
        return list;
 }
 
@@ -259,6 +285,7 @@ static void free_discovery(struct discovery *d)
                free(d->shallow.oid);
                free(d->buf_alloc);
                free_refs(d->refs);
+               free(d->service);
                free(d);
        }
 }
@@ -290,6 +317,19 @@ static int show_http_message(struct strbuf *type, struct strbuf *charset,
        return 0;
 }
 
+static int get_protocol_http_header(enum protocol_version version,
+                                   struct strbuf *header)
+{
+       if (version > 0) {
+               strbuf_addf(header, GIT_PROTOCOL_HEADER ": version=%d",
+                           version);
+
+               return 1;
+       }
+
+       return 0;
+}
+
 static struct discovery *discover_refs(const char *service, int for_push)
 {
        struct strbuf exp = STRBUF_INIT;
@@ -298,9 +338,12 @@ static struct discovery *discover_refs(const char *service, int for_push)
        struct strbuf buffer = STRBUF_INIT;
        struct strbuf refs_url = STRBUF_INIT;
        struct strbuf effective_url = STRBUF_INIT;
+       struct strbuf protocol_header = STRBUF_INIT;
+       struct string_list extra_headers = STRING_LIST_INIT_DUP;
        struct discovery *last = last_discovery;
        int http_ret, maybe_smart = 0;
        struct http_get_options http_options;
+       enum protocol_version version = get_protocol_version_config();
 
        if (last && !strcmp(service, last->service))
                return last;
@@ -317,11 +360,24 @@ static struct discovery *discover_refs(const char *service, int for_push)
                strbuf_addf(&refs_url, "service=%s", service);
        }
 
+       /*
+        * NEEDSWORK: If we are trying to use protocol v2 and we are planning
+        * to perform a push, then fallback to v0 since the client doesn't know
+        * how to push yet using v2.
+        */
+       if (version == protocol_v2 && !strcmp("git-receive-pack", service))
+               version = protocol_v0;
+
+       /* Add the extra Git-Protocol header */
+       if (get_protocol_http_header(version, &protocol_header))
+               string_list_append(&extra_headers, protocol_header.buf);
+
        memset(&http_options, 0, sizeof(http_options));
        http_options.content_type = &type;
        http_options.charset = &charset;
        http_options.effective_url = &effective_url;
        http_options.base_url = &url;
+       http_options.extra_headers = &extra_headers;
        http_options.initial_request = 1;
        http_options.no_cache = 1;
        http_options.keep_error = 1;
@@ -345,7 +401,7 @@ static struct discovery *discover_refs(const char *service, int for_push)
                warning(_("redirecting to %s"), url.buf);
 
        last= xcalloc(1, sizeof(*last_discovery));
-       last->service = service;
+       last->service = xstrdup(service);
        last->buf_alloc = strbuf_detach(&buffer, &last->len);
        last->buf = last->buf_alloc;
 
@@ -377,6 +433,9 @@ static struct discovery *discover_refs(const char *service, int for_push)
                        ;
 
                last->proto_git = 1;
+       } else if (maybe_smart &&
+                  last->len > 5 && starts_with(last->buf + 4, "version 2")) {
+               last->proto_git = 1;
        }
 
        if (last->proto_git)
@@ -390,6 +449,8 @@ static struct discovery *discover_refs(const char *service, int for_push)
        strbuf_release(&charset);
        strbuf_release(&effective_url);
        strbuf_release(&buffer);
+       strbuf_release(&protocol_header);
+       string_list_clear(&extra_headers, 0);
        last_discovery = last;
        return last;
 }
@@ -426,6 +487,7 @@ struct rpc_state {
        char *service_url;
        char *hdr_content_type;
        char *hdr_accept;
+       char *protocol_header;
        char *buf;
        size_t alloc;
        size_t len;
@@ -612,6 +674,10 @@ static int post_rpc(struct rpc_state *rpc)
        headers = curl_slist_append(headers, needs_100_continue ?
                "Expect: 100-continue" : "Expect:");
 
+       /* Add the extra Git-Protocol header */
+       if (rpc->protocol_header)
+               headers = curl_slist_append(headers, rpc->protocol_header);
+
 retry:
        slot = get_active_slot();
 
@@ -752,6 +818,11 @@ static int rpc_service(struct rpc_state *rpc, struct discovery *heads)
        strbuf_addf(&buf, "Accept: application/x-%s-result", svc);
        rpc->hdr_accept = strbuf_detach(&buf, NULL);
 
+       if (get_protocol_http_header(heads->version, &buf))
+               rpc->protocol_header = strbuf_detach(&buf, NULL);
+       else
+               rpc->protocol_header = NULL;
+
        while (!err) {
                int n = packet_read(rpc->out, NULL, NULL, rpc->buf, rpc->alloc, 0);
                if (!n)
@@ -779,6 +850,7 @@ static int rpc_service(struct rpc_state *rpc, struct discovery *heads)
        free(rpc->service_url);
        free(rpc->hdr_content_type);
        free(rpc->hdr_accept);
+       free(rpc->protocol_header);
        free(rpc->buf);
        strbuf_release(&buf);
        return err;
@@ -797,9 +869,6 @@ static int fetch_dumb(int nr_heads, struct ref **to_fetch)
                targets[i] = xstrdup(oid_to_hex(&to_fetch[i]->old_oid));
 
        walker = get_http_walker(url.buf);
-       walker->get_all = 1;
-       walker->get_tree = 1;
-       walker->get_history = 1;
        walker->get_verbosely = options.verbosity >= 3;
        walker->get_recover = 0;
        ret = walker_fetch(walker, nr_heads, targets, NULL, NULL);
@@ -1056,6 +1125,202 @@ static void parse_push(struct strbuf *buf)
        free(specs);
 }
 
+/*
+ * Used to represent the state of a connection to an HTTP server when
+ * communicating using git's wire-protocol version 2.
+ */
+struct proxy_state {
+       char *service_name;
+       char *service_url;
+       struct curl_slist *headers;
+       struct strbuf request_buffer;
+       int in;
+       int out;
+       struct packet_reader reader;
+       size_t pos;
+       int seen_flush;
+};
+
+static void proxy_state_init(struct proxy_state *p, const char *service_name,
+                            enum protocol_version version)
+{
+       struct strbuf buf = STRBUF_INIT;
+
+       memset(p, 0, sizeof(*p));
+       p->service_name = xstrdup(service_name);
+
+       p->in = 0;
+       p->out = 1;
+       strbuf_init(&p->request_buffer, 0);
+
+       strbuf_addf(&buf, "%s%s", url.buf, p->service_name);
+       p->service_url = strbuf_detach(&buf, NULL);
+
+       p->headers = http_copy_default_headers();
+
+       strbuf_addf(&buf, "Content-Type: application/x-%s-request", p->service_name);
+       p->headers = curl_slist_append(p->headers, buf.buf);
+       strbuf_reset(&buf);
+
+       strbuf_addf(&buf, "Accept: application/x-%s-result", p->service_name);
+       p->headers = curl_slist_append(p->headers, buf.buf);
+       strbuf_reset(&buf);
+
+       p->headers = curl_slist_append(p->headers, "Transfer-Encoding: chunked");
+
+       /* Add the Git-Protocol header */
+       if (get_protocol_http_header(version, &buf))
+               p->headers = curl_slist_append(p->headers, buf.buf);
+
+       packet_reader_init(&p->reader, p->in, NULL, 0,
+                          PACKET_READ_GENTLE_ON_EOF);
+
+       strbuf_release(&buf);
+}
+
+static void proxy_state_clear(struct proxy_state *p)
+{
+       free(p->service_name);
+       free(p->service_url);
+       curl_slist_free_all(p->headers);
+       strbuf_release(&p->request_buffer);
+}
+
+/*
+ * CURLOPT_READFUNCTION callback function.
+ * Attempts to copy over a single packet-line at a time into the
+ * curl provided buffer.
+ */
+static size_t proxy_in(char *buffer, size_t eltsize,
+                      size_t nmemb, void *userdata)
+{
+       size_t max;
+       struct proxy_state *p = userdata;
+       size_t avail = p->request_buffer.len - p->pos;
+
+
+       if (eltsize != 1)
+               BUG("curl read callback called with size = %"PRIuMAX" != 1",
+                   (uintmax_t)eltsize);
+       max = nmemb;
+
+       if (!avail) {
+               if (p->seen_flush) {
+                       p->seen_flush = 0;
+                       return 0;
+               }
+
+               strbuf_reset(&p->request_buffer);
+               switch (packet_reader_read(&p->reader)) {
+               case PACKET_READ_EOF:
+                       die("unexpected EOF when reading from parent process");
+               case PACKET_READ_NORMAL:
+                       packet_buf_write_len(&p->request_buffer, p->reader.line,
+                                            p->reader.pktlen);
+                       break;
+               case PACKET_READ_DELIM:
+                       packet_buf_delim(&p->request_buffer);
+                       break;
+               case PACKET_READ_FLUSH:
+                       packet_buf_flush(&p->request_buffer);
+                       p->seen_flush = 1;
+                       break;
+               }
+               p->pos = 0;
+               avail = p->request_buffer.len;
+       }
+
+       if (max < avail)
+               avail = max;
+       memcpy(buffer, p->request_buffer.buf + p->pos, avail);
+       p->pos += avail;
+       return avail;
+}
+
+static size_t proxy_out(char *buffer, size_t eltsize,
+                       size_t nmemb, void *userdata)
+{
+       size_t size;
+       struct proxy_state *p = userdata;
+
+       if (eltsize != 1)
+               BUG("curl read callback called with size = %"PRIuMAX" != 1",
+                   (uintmax_t)eltsize);
+       size = nmemb;
+
+       write_or_die(p->out, buffer, size);
+       return size;
+}
+
+/* Issues a request to the HTTP server configured in `p` */
+static int proxy_request(struct proxy_state *p)
+{
+       struct active_request_slot *slot;
+
+       slot = get_active_slot();
+
+       curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 0);
+       curl_easy_setopt(slot->curl, CURLOPT_POST, 1);
+       curl_easy_setopt(slot->curl, CURLOPT_URL, p->service_url);
+       curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, p->headers);
+
+       /* Setup function to read request from client */
+       curl_easy_setopt(slot->curl, CURLOPT_READFUNCTION, proxy_in);
+       curl_easy_setopt(slot->curl, CURLOPT_READDATA, p);
+
+       /* Setup function to write server response to client */
+       curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, proxy_out);
+       curl_easy_setopt(slot->curl, CURLOPT_WRITEDATA, p);
+
+       if (run_slot(slot, NULL) != HTTP_OK)
+               return -1;
+
+       return 0;
+}
+
+static int stateless_connect(const char *service_name)
+{
+       struct discovery *discover;
+       struct proxy_state p;
+
+       /*
+        * Run the info/refs request and see if the server supports protocol
+        * v2.  If and only if the server supports v2 can we successfully
+        * establish a stateless connection, otherwise we need to tell the
+        * client to fallback to using other transport helper functions to
+        * complete their request.
+        */
+       discover = discover_refs(service_name, 0);
+       if (discover->version != protocol_v2) {
+               printf("fallback\n");
+               fflush(stdout);
+               return -1;
+       } else {
+               /* Stateless Connection established */
+               printf("\n");
+               fflush(stdout);
+       }
+
+       proxy_state_init(&p, service_name, discover->version);
+
+       /*
+        * Dump the capability listing that we got from the server earlier
+        * during the info/refs request.
+        */
+       write_or_die(p.out, discover->buf, discover->len);
+
+       /* Peek the next packet line.  Until we see EOF keep sending POSTs */
+       while (packet_reader_peek(&p.reader) != PACKET_READ_EOF) {
+               if (proxy_request(&p)) {
+                       /* We would have an err here */
+                       break;
+               }
+       }
+
+       proxy_state_clear(&p);
+       return 0;
+}
+
 int cmd_main(int argc, const char **argv)
 {
        struct strbuf buf = STRBUF_INIT;
@@ -1124,12 +1389,16 @@ int cmd_main(int argc, const char **argv)
                        fflush(stdout);
 
                } else if (!strcmp(buf.buf, "capabilities")) {
+                       printf("stateless-connect\n");
                        printf("fetch\n");
                        printf("option\n");
                        printf("push\n");
                        printf("check-connectivity\n");
                        printf("\n");
                        fflush(stdout);
+               } else if (skip_prefix(buf.buf, "stateless-connect ", &arg)) {
+                       if (!stateless_connect(arg))
+                               break;
                } else {
                        error("remote-curl: unknown command '%s' from git", buf.buf);
                        return 1;