[PATCH v3 3/8] upload/receive-pack: allow hiding ref hierarchies
- From
Junio C Hamano <gitster@pobox.com>
- Date
- Jan 30, 2013, 18:45 UTC
- Message-ID
- <1359571542-19852-4-git-send-email-gitster@pobox.com>
- In-Reply-To
- <1359571542-19852-1-git-send-email-gitster@pobox.com>
Teach upload-pack and receive-pack to omit some refs from their initial advertisements by paying attention to the transfer.hiderefs multi-valued configuration variable. Any ref that is under the hierarchies listed on the value of this variable is excluded from responses to requests made by "ls-remote", "fetch", "clone", "push", etc.
A typical use case may be
[transfer] hiderefs = refs/pull
to hide the refs that are internally used by the hosting site and should not be exposed over the network.
Because these hidden refs do not count as OUR_REF, an attempt to fetch objects at the tip of them will be rejected, and because these refs do not get advertised, "git push :" will not see local branches that have the same name as them as "matching" ones to be sent.
An attempt to update/delete these hidden refs with an explicit refspec, e.g. "git push origin :refs/pull/11/head", is rejected.
This is not a new restriction. To the pusher, it would appear that there is no such ref, so its push request will conclude with "Now that I sent you all the data, it is time for you to update the refs. I saw that the ref did not exist when I started pushing, and I want the result to point at this commit". The receiving end will apply the compare-and-swap rule to this request and rejects the push with "Well, your update request conflicts with somebody else; I see there is such a ref.", which is the right thing to do. Otherwise a push to a hidden ref will always be "the last one wins", which is not a good default.
Signed-off-by: Junio C Hamano <gitster@pobox.com> --- Documentation/config.txt | 11 +++++++++++ builtin/receive-pack.c | 24 ++++++++++++++++++++++++ refs.c | 41 +++++++++++++++++++++++++++++++++++++++++ refs.h | 3 +++ t/t5512-ls-remote.sh | 9 +++++++++ t/t5516-fetch-push.sh | 24 ++++++++++++++++++++++++ upload-pack.c | 14 +++++++++++++- 7 files changed, 125 insertions(+), 1 deletion(-)
diff --git a/Documentation/config.txt b/Documentation/config.txt index ef45c99..f57c802 100644 --- a/Documentation/config.txt +++ b/Documentation/config.txt @@ -2057,6 +2057,17 @@ transfer.fsckObjects:: not set, the value of this variable is used instead. Defaults to false. +transfer.hiderefs:: + String(s) `upload-pack` and `receive-pack` use to decide + which refs to omit from their initial advertisement. Use + more than one transfer.hiderefs configuration variables to + specify multiple prefix strings. A ref that are under the + hierarchies listed on the value of this variable is excluded, + and is hidden from `git ls-remote`, `git fetch`, `git push :`, + etc. An attempt to update or delete a hidden ref by `git push` + is rejected, and an attempt to fetch a hidden ref by `git fetch` + will fail. + transfer.unpackLimit:: When `fetch.unpackLimit` or `receive.unpackLimit` are not set, the value of this variable is used instead. diff --git a/builtin/receive-pack.c b/builtin/receive-pack.c index ff781fe..a8248d9 100644 --- a/builtin/receive-pack.c +++ b/builtin/receive-pack.c @@ -59,6 +59,11 @@ static enum deny_action parse_deny_action(const char *var, const char *value) static int receive_pack_config(const char *var, const char *value, void *cb) { + int status = parse_hide_refs_config(var, value, cb); + + if (status) + return status; + if (strcmp(var, "receive.denydeletes") == 0) { deny_deletes = git_config_bool(var, value); return 0; @@ -119,6 +124,9 @@ static int receive_pack_config(const char *var, const char *value, void *cb) static void show_ref(const char *path, const unsigned char *sha1) { + if (ref_is_hidden(path)) + return; + if (sent_capabilities) packet_write(1, "%s %s\n", sha1_to_hex(sha1), path); else @@ -688,6 +696,20 @@ static int iterate_receive_command_list(void *cb_data, unsigned char sha1[20]) return -1; /* end of list */ } +static void reject_updates_to_hidden(struct command *commands) +{ + struct command *cmd; + + for (cmd = commands; cmd; cmd = cmd->next) { + if (cmd->error_string || !ref_is_hidden(cmd->ref_name)) + continue; + if (is_null_sha1(cmd->new_sha1)) + cmd->error_string = "deny deleting a hidden ref"; + else + cmd->error_string = "deny updating a hidden ref"; + } +} + static void execute_commands(struct command *commands, const char *unpacker_error) { struct command *cmd; @@ -704,6 +726,8 @@ static void execute_commands(struct command *commands, const char *unpacker_erro 0, &cmd)) set_connectivity_errors(commands); + reject_updates_to_hidden(commands); + if (run_receive_hook(commands, pre_receive_hook, 0)) { for (cmd = commands; cmd; cmd = cmd->next) { if (!cmd->error_string) diff --git a/refs.c b/refs.c index 541fec2..e3574ca 100644 --- a/refs.c +++ b/refs.c @@ -3,6 +3,7 @@ #include "object.h" #include "tag.h" #include "dir.h" +#include "string-list.h" /* * Make sure "ref" is something reasonable to have under ".git/refs/"; @@ -2556,3 +2557,43 @@ char *shorten_unambiguous_ref(const char *refname, int strict) free(short_name); return xstrdup(refname); } + +static struct string_list *hide_refs; + +int parse_hide_refs_config(const char *var, const char *value, void *unused) +{ + if (!strcmp("transfer.hiderefs", var)) { + char *ref; + int len; + + if (!value) + return config_error_nonbool(var); + ref = xstrdup(value); + len = strlen(ref); + while (len && ref[len - 1] == '/') + ref[--len] = '\0'; + if (!hide_refs) { + hide_refs = xcalloc(1, sizeof(*hide_refs)); + hide_refs->strdup_strings = 1; + } + string_list_append(hide_refs, ref); + } + return 0; +} + +int ref_is_hidden(const char *refname) +{ + struct string_list_item *item; + + if (!hide_refs) + return 0; + for_each_string_list_item(item, hide_refs) { + int len; + if (prefixcmp(refname, item->string)) + continue; + len = strlen(item->string); + if (!refname[len] || refname[len] == '/') + return 1; + } + return 0; +} diff --git a/refs.h b/refs.h index d6c2fe2..50b233f 100644 --- a/refs.h +++ b/refs.h @@ -147,4 +147,7 @@ int update_ref(const char *action, const char *refname, const unsigned char *sha1, const unsigned char *oldval, int flags, enum action_on_err onerr); +extern int parse_hide_refs_config(const char *var, const char *value, void *); +extern int ref_is_hidden(const char *); + #endif /* REFS_H */ diff --git a/t/t5512-ls-remote.sh b/t/t5512-ls-remote.sh index d16e5d3..d0702ed 100755 --- a/t/t5512-ls-remote.sh +++ b/t/t5512-ls-remote.sh @@ -126,4 +126,13 @@ test_expect_success 'Report match with --exit-code' ' test_cmp expect actual ' +test_expect_success 'Hide some refs' ' + test_config transfer.hiderefs refs/tags && + git ls-remote . >actual && + test_unconfig transfer.hiderefs && + git ls-remote . | + sed -e "/ refs\/tags\//d" >expect && + test_cmp expect actual +' + test_done diff --git a/t/t5516-fetch-push.sh b/t/t5516-fetch-push.sh index 6009372..852efb6 100755 --- a/t/t5516-fetch-push.sh +++ b/t/t5516-fetch-push.sh @@ -1037,4 +1037,28 @@ test_expect_success 'push --prune refspec' ' ! check_push_result $the_first_commit tmp/foo tmp/bar ' +test_expect_success 'push to update a hidden ref' ' + mk_test heads/master hidden/one hidden/two hidden/three && + ( + cd testrepo && + git config transfer.hiderefs refs/hidden + ) && + + # push to unhidden ref succeeds normally + git push testrepo master:refs/heads/master && + check_push_result $the_commit heads/master && + + # push to update a hidden ref should fail + test_must_fail git push testrepo master:refs/hidden/one && + check_push_result $the_first_commit hidden/one && + + # push to delete a hidden ref should fail + test_must_fail git push testrepo :refs/hidden/two && + check_push_result $the_first_commit hidden/two && + + # idempotent push to update a hidden ref should fail + test_must_fail git push testrepo $the_first_commit:refs/hidden/three && + check_push_result $the_first_commit hidden/three +' + test_done diff --git a/upload-pack.c b/upload-pack.c index 3a26a7b..6b10843 100644 --- a/upload-pack.c +++ b/upload-pack.c @@ -12,6 +12,7 @@ #include "run-command.h" #include "sigchain.h" #include "version.h" +#include "string-list.h" static const char upload_pack_usage[] = "git upload-pack [--strict] [--timeout=<n>] <dir>"; @@ -719,9 +720,13 @@ static void receive_needs(void) free(shallows.objects); } +/* return non-zero if the ref is hidden, otherwise 0 */ static int mark_our_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data) { struct object *o = lookup_unknown_object(sha1); + + if (ref_is_hidden(refname)) + return 1; if (!o) die("git upload-pack: cannot find object %s:", sha1_to_hex(sha1)); o->flags |= OUR_REF; @@ -736,7 +741,8 @@ static int send_ref(const char *refname, const unsigned char *sha1, int flag, vo const char *refname_nons = strip_namespace(refname); unsigned char peeled[20]; - mark_our_ref(refname, sha1, flag, cb_data); + if (mark_our_ref(refname, sha1, flag, cb_data)) + return 0; if (capabilities) packet_write(1, "%s %s%c%s%s agent=%s\n", @@ -773,6 +779,11 @@ static void upload_pack(void) } } +static int upload_pack_config(const char *var, const char *value, void *unused) +{ + return parse_hide_refs_config(var, value, unused); +} + int main(int argc, char **argv) { char *dir; @@ -824,6 +835,7 @@ int main(int argc, char **argv) die("'%s' does not appear to be a git repository", dir); if (is_repository_shallow()) die("attempt to fetch/clone from a shallow repository"); + git_config(upload_pack_config, NULL); if (getenv("GIT_DEBUG_SEND_PACK")) debug_fd = atoi(getenv("GIT_DEBUG_SEND_PACK")); upload_pack();
-- 1.8.1.2.589.ga9b91ac