Merge branch 'tc/clone-v-progress'
[git/git.git] / transport-helper.c
index bfe3bc3..ca8fa92 100644 (file)
@@ -6,6 +6,9 @@
 #include "diff.h"
 #include "revision.h"
 #include "quote.h"
+#include "remote.h"
+
+static int debug;
 
 struct helper_data
 {
@@ -13,15 +16,92 @@ struct helper_data
        struct child_process *helper;
        FILE *out;
        unsigned fetch : 1,
+               import : 1,
                option : 1,
-               push : 1;
+               push : 1,
+               connect : 1,
+               no_disconnect_req : 1;
+       /* These go from remote name (as in "list") to private name */
+       struct refspec *refspecs;
+       int refspec_nr;
+       /* Transport options for fetch-pack/send-pack (should one of
+        * those be invoked).
+        */
+       struct git_transport_options transport_options;
 };
 
+static void sendline(struct helper_data *helper, struct strbuf *buffer)
+{
+       if (debug)
+               fprintf(stderr, "Debug: Remote helper: -> %s", buffer->buf);
+       if (write_in_full(helper->helper->in, buffer->buf, buffer->len)
+               != buffer->len)
+               die_errno("Full write to remote helper failed");
+}
+
+static int recvline_fh(FILE *helper, struct strbuf *buffer)
+{
+       strbuf_reset(buffer);
+       if (debug)
+               fprintf(stderr, "Debug: Remote helper: Waiting...\n");
+       if (strbuf_getline(buffer, helper, '\n') == EOF) {
+               if (debug)
+                       fprintf(stderr, "Debug: Remote helper quit.\n");
+               exit(128);
+       }
+
+       if (debug)
+               fprintf(stderr, "Debug: Remote helper: <- %s\n", buffer->buf);
+       return 0;
+}
+
+static int recvline(struct helper_data *helper, struct strbuf *buffer)
+{
+       return recvline_fh(helper->out, buffer);
+}
+
+static void xchgline(struct helper_data *helper, struct strbuf *buffer)
+{
+       sendline(helper, buffer);
+       recvline(helper, buffer);
+}
+
+static void write_constant(int fd, const char *str)
+{
+       if (debug)
+               fprintf(stderr, "Debug: Remote helper: -> %s", str);
+       if (write_in_full(fd, str, strlen(str)) != strlen(str))
+               die_errno("Full write to remote helper failed");
+}
+
+const char *remove_ext_force(const char *url)
+{
+       if (url) {
+               const char *colon = strchr(url, ':');
+               if (colon && colon[1] == ':')
+                       return colon + 2;
+       }
+       return url;
+}
+
+static void do_take_over(struct transport *transport)
+{
+       struct helper_data *data;
+       data = (struct helper_data *)transport->data;
+       transport_take_over(transport, data->helper);
+       fclose(data->out);
+       free(data);
+}
+
 static struct child_process *get_helper(struct transport *transport)
 {
        struct helper_data *data = transport->data;
        struct strbuf buf = STRBUF_INIT;
        struct child_process *helper;
+       const char **refspecs = NULL;
+       int refspec_nr = 0;
+       int refspec_alloc = 0;
+       int duped;
 
        if (data->helper)
                return data->helper;
@@ -34,37 +114,91 @@ static struct child_process *get_helper(struct transport *transport)
        strbuf_addf(&buf, "remote-%s", data->name);
        helper->argv[0] = strbuf_detach(&buf, NULL);
        helper->argv[1] = transport->remote->name;
-       helper->argv[2] = transport->url;
+       helper->argv[2] = remove_ext_force(transport->url);
        helper->git_cmd = 1;
        if (start_command(helper))
                die("Unable to run helper: git %s", helper->argv[0]);
        data->helper = helper;
+       data->no_disconnect_req = 0;
 
-       write_str_in_full(helper->in, "capabilities\n");
+       /*
+        * Open the output as FILE* so strbuf_getline() can be used.
+        * Do this with duped fd because fclose() will close the fd,
+        * and stuff like taking over will require the fd to remain.
+        */
+       duped = dup(helper->out);
+       if (duped < 0)
+               die_errno("Can't dup helper output fd");
+       data->out = xfdopen(duped, "r");
+
+       write_constant(helper->in, "capabilities\n");
 
-       data->out = xfdopen(helper->out, "r");
        while (1) {
-               if (strbuf_getline(&buf, data->out, '\n') == EOF)
-                       exit(128); /* child died, message supplied already */
+               const char *capname;
+               int mandatory = 0;
+               recvline(data, &buf);
 
                if (!*buf.buf)
                        break;
-               if (!strcmp(buf.buf, "fetch"))
+
+               if (*buf.buf == '*') {
+                       capname = buf.buf + 1;
+                       mandatory = 1;
+               } else
+                       capname = buf.buf;
+
+               if (debug)
+                       fprintf(stderr, "Debug: Got cap %s\n", capname);
+               if (!strcmp(capname, "fetch"))
                        data->fetch = 1;
-               if (!strcmp(buf.buf, "option"))
+               else if (!strcmp(capname, "option"))
                        data->option = 1;
-               if (!strcmp(buf.buf, "push"))
+               else if (!strcmp(capname, "push"))
                        data->push = 1;
+               else if (!strcmp(capname, "import"))
+                       data->import = 1;
+               else if (!data->refspecs && !prefixcmp(capname, "refspec ")) {
+                       ALLOC_GROW(refspecs,
+                                  refspec_nr + 1,
+                                  refspec_alloc);
+                       refspecs[refspec_nr++] = strdup(buf.buf + strlen("refspec "));
+               } else if (!strcmp(capname, "connect")) {
+                       data->connect = 1;
+               } else if (mandatory) {
+                       die("Unknown madatory capability %s. This remote "
+                           "helper probably needs newer version of Git.\n",
+                           capname);
+               }
+       }
+       if (refspecs) {
+               int i;
+               data->refspec_nr = refspec_nr;
+               data->refspecs = parse_fetch_refspec(refspec_nr, refspecs);
+               for (i = 0; i < refspec_nr; i++) {
+                       free((char *)refspecs[i]);
+               }
+               free(refspecs);
        }
+       strbuf_release(&buf);
+       if (debug)
+               fprintf(stderr, "Debug: Capabilities complete.\n");
        return data->helper;
 }
 
 static int disconnect_helper(struct transport *transport)
 {
        struct helper_data *data = transport->data;
+       struct strbuf buf = STRBUF_INIT;
+
        if (data->helper) {
-               write_str_in_full(data->helper->in, "\n");
+               if (debug)
+                       fprintf(stderr, "Debug: Disconnecting.\n");
+               if (!data->no_disconnect_req) {
+                       strbuf_addf(&buf, "\n");
+                       sendline(data, &buf);
+               }
                close(data->helper->in);
+               close(data->helper->out);
                fclose(data->out);
                finish_command(data->helper);
                free((char *)data->helper->argv[0]);
@@ -72,7 +206,6 @@ static int disconnect_helper(struct transport *transport)
                free(data->helper);
                data->helper = NULL;
        }
-       free(data);
        return 0;
 }
 
@@ -92,10 +225,11 @@ static int set_helper_option(struct transport *transport,
                          const char *name, const char *value)
 {
        struct helper_data *data = transport->data;
-       struct child_process *helper = get_helper(transport);
        struct strbuf buf = STRBUF_INIT;
        int i, ret, is_bool = 0;
 
+       get_helper(transport);
+
        if (!data->option)
                return 1;
 
@@ -118,12 +252,7 @@ static int set_helper_option(struct transport *transport,
                quote_c_style(value, &buf, NULL, 0);
        strbuf_addch(&buf, '\n');
 
-       if (write_in_full(helper->in, buf.buf, buf.len) != buf.len)
-               die_errno("cannot send option to %s", data->name);
-
-       strbuf_reset(&buf);
-       if (strbuf_getline(&buf, data->out, '\n') == EOF)
-               exit(128); /* child died, message supplied already */
+       xchgline(data, &buf);
 
        if (!strcmp(buf.buf, "ok"))
                ret = 0;
@@ -154,8 +283,18 @@ static void standard_options(struct transport *t)
        set_helper_option(t, "verbosity", buf);
 }
 
+static int release_helper(struct transport *transport)
+{
+       struct helper_data *data = transport->data;
+       free_refspec(data->refspec_nr, data->refspecs);
+       data->refspecs = NULL;
+       disconnect_helper(transport);
+       free(transport->data);
+       return 0;
+}
+
 static int fetch_with_fetch(struct transport *transport,
-                           int nr_heads, const struct ref **to_fetch)
+                           int nr_heads, struct ref **to_fetch)
 {
        struct helper_data *data = transport->data;
        int i;
@@ -173,13 +312,10 @@ static int fetch_with_fetch(struct transport *transport,
        }
 
        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);
+       sendline(data, &buf);
 
        while (1) {
-               strbuf_reset(&buf);
-               if (strbuf_getline(&buf, data->out, '\n') == EOF)
-                       exit(128); /* child died, message supplied already */
+               recvline(data, &buf);
 
                if (!prefixcmp(buf.buf, "lock ")) {
                        const char *name = buf.buf + 5;
@@ -197,12 +333,169 @@ static int fetch_with_fetch(struct transport *transport,
        return 0;
 }
 
+static int get_importer(struct transport *transport, struct child_process *fastimport)
+{
+       struct child_process *helper = get_helper(transport);
+       memset(fastimport, 0, sizeof(*fastimport));
+       fastimport->in = helper->out;
+       fastimport->argv = xcalloc(5, sizeof(*fastimport->argv));
+       fastimport->argv[0] = "fast-import";
+       fastimport->argv[1] = "--quiet";
+
+       fastimport->git_cmd = 1;
+       return start_command(fastimport);
+}
+
+static int fetch_with_import(struct transport *transport,
+                            int nr_heads, struct ref **to_fetch)
+{
+       struct child_process fastimport;
+       struct helper_data *data = transport->data;
+       int i;
+       struct ref *posn;
+       struct strbuf buf = STRBUF_INIT;
+
+       get_helper(transport);
+
+       if (get_importer(transport, &fastimport))
+               die("Couldn't run fast-import");
+
+       for (i = 0; i < nr_heads; i++) {
+               posn = to_fetch[i];
+               if (posn->status & REF_STATUS_UPTODATE)
+                       continue;
+
+               strbuf_addf(&buf, "import %s\n", posn->name);
+               sendline(data, &buf);
+               strbuf_reset(&buf);
+       }
+       disconnect_helper(transport);
+       finish_command(&fastimport);
+       free(fastimport.argv);
+       fastimport.argv = NULL;
+
+       for (i = 0; i < nr_heads; i++) {
+               char *private;
+               posn = to_fetch[i];
+               if (posn->status & REF_STATUS_UPTODATE)
+                       continue;
+               if (data->refspecs)
+                       private = apply_refspecs(data->refspecs, data->refspec_nr, posn->name);
+               else
+                       private = strdup(posn->name);
+               read_ref(private, posn->old_sha1);
+               free(private);
+       }
+       strbuf_release(&buf);
+       return 0;
+}
+
+static int process_connect_service(struct transport *transport,
+                                  const char *name, const char *exec)
+{
+       struct helper_data *data = transport->data;
+       struct strbuf cmdbuf = STRBUF_INIT;
+       struct child_process *helper;
+       int r, duped, ret = 0;
+       FILE *input;
+
+       helper = get_helper(transport);
+
+       /*
+        * Yes, dup the pipe another time, as we need unbuffered version
+        * of input pipe as FILE*. fclose() closes the underlying fd and
+        * stream buffering only can be changed before first I/O operation
+        * on it.
+        */
+       duped = dup(helper->out);
+       if (duped < 0)
+               die_errno("Can't dup helper output fd");
+       input = xfdopen(duped, "r");
+       setvbuf(input, NULL, _IONBF, 0);
+
+       /*
+        * Handle --upload-pack and friends. This is fire and forget...
+        * just warn if it fails.
+        */
+       if (strcmp(name, exec)) {
+               r = set_helper_option(transport, "servpath", exec);
+               if (r > 0)
+                       warning("Setting remote service path not supported by protocol.");
+               else if (r < 0)
+                       warning("Invalid remote service path.");
+       }
+
+       if (data->connect)
+               strbuf_addf(&cmdbuf, "connect %s\n", name);
+       else
+               goto exit;
+
+       sendline(data, &cmdbuf);
+       recvline_fh(input, &cmdbuf);
+       if (!strcmp(cmdbuf.buf, "")) {
+               data->no_disconnect_req = 1;
+               if (debug)
+                       fprintf(stderr, "Debug: Smart transport connection "
+                               "ready.\n");
+               ret = 1;
+       } else if (!strcmp(cmdbuf.buf, "fallback")) {
+               if (debug)
+                       fprintf(stderr, "Debug: Falling back to dumb "
+                               "transport.\n");
+       } else
+               die("Unknown response to connect: %s",
+                       cmdbuf.buf);
+
+exit:
+       fclose(input);
+       return ret;
+}
+
+static int process_connect(struct transport *transport,
+                                    int for_push)
+{
+       struct helper_data *data = transport->data;
+       const char *name;
+       const char *exec;
+
+       name = for_push ? "git-receive-pack" : "git-upload-pack";
+       if (for_push)
+               exec = data->transport_options.receivepack;
+       else
+               exec = data->transport_options.uploadpack;
+
+       return process_connect_service(transport, name, exec);
+}
+
+static int connect_helper(struct transport *transport, const char *name,
+                  const char *exec, int fd[2])
+{
+       struct helper_data *data = transport->data;
+
+       /* Get_helper so connect is inited. */
+       get_helper(transport);
+       if (!data->connect)
+               die("Operation not supported by protocol.");
+
+       if (!process_connect_service(transport, name, exec))
+               die("Can't connect to subservice %s.", name);
+
+       fd[0] = data->helper->out;
+       fd[1] = data->helper->in;
+       return 0;
+}
+
 static int fetch(struct transport *transport,
-                int nr_heads, const struct ref **to_fetch)
+                int nr_heads, struct ref **to_fetch)
 {
        struct helper_data *data = transport->data;
        int i, count;
 
+       if (process_connect(transport, 0)) {
+               do_take_over(transport);
+               return transport->fetch(transport, nr_heads, to_fetch);
+       }
+
        count = 0;
        for (i = 0; i < nr_heads; i++)
                if (!(to_fetch[i]->status & REF_STATUS_UPTODATE))
@@ -214,6 +507,9 @@ static int fetch(struct transport *transport,
        if (data->fetch)
                return fetch_with_fetch(transport, nr_heads, to_fetch);
 
+       if (data->import)
+               return fetch_with_import(transport, nr_heads, to_fetch);
+
        return -1;
 }
 
@@ -227,6 +523,11 @@ static int push_refs(struct transport *transport,
        struct child_process *helper;
        struct ref *ref;
 
+       if (process_connect(transport, 1)) {
+               do_take_over(transport);
+               return transport->push_refs(transport, remote_refs, flags);
+       }
+
        if (!remote_refs)
                return 0;
 
@@ -275,17 +576,14 @@ static int push_refs(struct transport *transport,
        }
 
        strbuf_addch(&buf, '\n');
-       if (write_in_full(helper->in, buf.buf, buf.len) != buf.len)
-               exit(128);
+       sendline(data, &buf);
 
        ref = remote_refs;
        while (1) {
                char *refname, *msg;
                int status;
 
-               strbuf_reset(&buf);
-               if (strbuf_getline(&buf, data->out, '\n') == EOF)
-                       exit(128); /* child died, message supplied already */
+               recvline(data, &buf);
                if (!buf.len)
                        break;
 
@@ -343,6 +641,22 @@ static int push_refs(struct transport *transport,
        return 0;
 }
 
+static int has_attribute(const char *attrs, const char *attr) {
+       int len;
+       if (!attrs)
+               return 0;
+
+       len = strlen(attr);
+       for (;;) {
+               const char *space = strchrnul(attrs, ' ');
+               if (len == space - attrs && !strncmp(attrs, attr, len))
+                       return 1;
+               if (!*space)
+                       return 0;
+               attrs = space + 1;
+       }
+}
+
 static struct ref *get_refs_list(struct transport *transport, int for_push)
 {
        struct helper_data *data = transport->data;
@@ -354,6 +668,11 @@ static struct ref *get_refs_list(struct transport *transport, int for_push)
 
        helper = get_helper(transport);
 
+       if (process_connect(transport, for_push)) {
+               do_take_over(transport);
+               return transport->get_refs_list(transport, for_push);
+       }
+
        if (data->push && for_push)
                write_str_in_full(helper->in, "list for-push\n");
        else
@@ -361,8 +680,7 @@ static struct ref *get_refs_list(struct transport *transport, int for_push)
 
        while (1) {
                char *eov, *eon;
-               if (strbuf_getline(&buf, data->out, '\n') == EOF)
-                       exit(128); /* child died, message supplied already */
+               recvline(data, &buf);
 
                if (!*buf.buf)
                        break;
@@ -379,8 +697,16 @@ static struct ref *get_refs_list(struct transport *transport, int for_push)
                        (*tail)->symref = xstrdup(buf.buf + 1);
                else if (buf.buf[0] != '?')
                        get_sha1_hex(buf.buf, (*tail)->old_sha1);
+               if (eon) {
+                       if (has_attribute(eon + 1, "unchanged")) {
+                               (*tail)->status |= REF_STATUS_UPTODATE;
+                               read_ref((*tail)->name, (*tail)->old_sha1);
+                       }
+               }
                tail = &((*tail)->next);
        }
+       if (debug)
+               fprintf(stderr, "Debug: Read ref listing.\n");
        strbuf_release(&buf);
 
        for (posn = ret; posn; posn = posn->next)
@@ -394,11 +720,16 @@ int transport_helper_init(struct transport *transport, const char *name)
        struct helper_data *data = xcalloc(sizeof(*data), 1);
        data->name = name;
 
+       if (getenv("GIT_TRANSPORT_HELPER_DEBUG"))
+               debug = 1;
+
        transport->data = data;
        transport->set_option = set_helper_option;
        transport->get_refs_list = get_refs_list;
        transport->fetch = fetch;
        transport->push_refs = push_refs;
-       transport->disconnect = disconnect_helper;
+       transport->disconnect = release_helper;
+       transport->connect = connect_helper;
+       transport->smart_options = &(data->transport_options);
        return 0;
 }