* [PATCHv9 1/4] Fix prefix handling in ref iteration functions
2011-07-05 17:54 [PATCHv9 0/4] ref namespaces Josh Triplett
@ 2011-07-05 17:54 ` Josh Triplett
2011-07-05 17:54 ` [PATCHv9 2/4] ref namespaces: infrastructure Josh Triplett
` (2 subsequent siblings)
3 siblings, 0 replies; 7+ messages in thread
From: Josh Triplett @ 2011-07-05 17:54 UTC (permalink / raw)
To: Junio C Hamano
Cc: Jamey Sharp, Shawn O. Pearce, Johannes Schindelin, Jeff King,
Jakub Narebski, Bert Wesarg, git
The do_for_each_ref iteration function accepts a prefix and a trim, and
checks for the prefix on each ref before passing in that ref; it also
supports trimming off part of the ref before passing it. However,
do_for_each_ref used trim as the length of the prefix to check, ignoring
the actual length of the prefix. Switch to using prefixcmp, checking
the entire length of the prefix string, to properly support a trim value
different than the length of the prefix.
Several callers passed a prefix of "refs/" to filter out everything
outside of refs/, but a trim of 0 to avoid trimming off the "refs/"; the
trim of 0 meant that the filter of "refs/" no longer applied. Change
these callers to pass an empty prefix instead, to avoid changing the
existing behavior. Various callers count on this lack of filtering,
such as receive-pack which uses add_extra_ref to add alternates as refs
named ".have"; adding filtering would break that, causing
t5501-fetch-push-alternates.sh to fail. That lack of filtering doesn't
currently have any other effect, since the loose ref functions can never
supply refs outside of "refs/", and packed-refs will not normally
include such refs unless manually edited.
Signed-off-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Jamey Sharp <jamey@minilop.net>
---
refs.c | 8 ++++----
1 files changed, 4 insertions(+), 4 deletions(-)
diff --git a/refs.c b/refs.c
index 3a8789d..8bf8bb6 100644
--- a/refs.c
+++ b/refs.c
@@ -584,7 +584,7 @@ int read_ref(const char *ref, unsigned char *sha1)
static int do_one_ref(const char *base, each_ref_fn fn, int trim,
int flags, void *cb_data, struct ref_list *entry)
{
- if (strncmp(base, entry->name, trim))
+ if (prefixcmp(entry->name, base))
return 0;
if (!(flags & DO_FOR_EACH_INCLUDE_BROKEN)) {
@@ -728,12 +728,12 @@ int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
int for_each_ref(each_ref_fn fn, void *cb_data)
{
- return do_for_each_ref(NULL, "refs/", fn, 0, 0, cb_data);
+ return do_for_each_ref(NULL, "", fn, 0, 0, cb_data);
}
int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data)
{
- return do_for_each_ref(submodule, "refs/", fn, 0, 0, cb_data);
+ return do_for_each_ref(submodule, "", fn, 0, 0, cb_data);
}
int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
@@ -819,7 +819,7 @@ int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data)
int for_each_rawref(each_ref_fn fn, void *cb_data)
{
- return do_for_each_ref(NULL, "refs/", fn, 0,
+ return do_for_each_ref(NULL, "", fn, 0,
DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
}
--
1.7.5.4
^ permalink raw reply related [flat|nested] 7+ messages in thread* [PATCHv9 2/4] ref namespaces: infrastructure
2011-07-05 17:54 [PATCHv9 0/4] ref namespaces Josh Triplett
2011-07-05 17:54 ` [PATCHv9 1/4] Fix prefix handling in ref iteration functions Josh Triplett
@ 2011-07-05 17:54 ` Josh Triplett
2011-07-05 17:55 ` [PATCHv9 3/4] ref namespaces: Support remote repositories via upload-pack and receive-pack Josh Triplett
2011-07-05 17:55 ` [PATCHv9 4/4] ref namespaces: documentation Josh Triplett
3 siblings, 0 replies; 7+ messages in thread
From: Josh Triplett @ 2011-07-05 17:54 UTC (permalink / raw)
To: Junio C Hamano
Cc: Jamey Sharp, Shawn O. Pearce, Johannes Schindelin, Jeff King,
Jakub Narebski, Bert Wesarg, git
Add support for dividing the refs of a single repository into multiple
namespaces, each of which can have its own branches, tags, and HEAD.
Git can expose each namespace as an independent repository to pull from
and push to, while sharing the object store, and exposing all the refs
to operations such as git-gc.
Storing multiple repositories as namespaces of a single repository
avoids storing duplicate copies of the same objects, such as when
storing multiple branches of the same source. The alternates mechanism
provides similar support for avoiding duplicates, but alternates do not
prevent duplication between new objects added to the repositories
without ongoing maintenance, while namespaces do.
To specify a namespace, set the GIT_NAMESPACE environment variable to
the namespace. For each ref namespace, git stores the corresponding
refs in a directory under refs/namespaces/. For example,
GIT_NAMESPACE=foo will store refs under refs/namespaces/foo/. You can
also specify namespaces via the --namespace option to git.
Note that namespaces which include a / will expand to a hierarchy of
namespaces; for example, GIT_NAMESPACE=foo/bar will store refs under
refs/namespaces/foo/refs/namespaces/bar/. This makes paths in
GIT_NAMESPACE behave hierarchically, so that cloning with
GIT_NAMESPACE=foo/bar produces the same result as cloning with
GIT_NAMESPACE=foo and cloning from that repo with GIT_NAMESPACE=bar. It
also avoids ambiguity with strange namespace paths such as
foo/refs/heads/, which could otherwise generate directory/file conflicts
within the refs directory.
Add the infrastructure for ref namespaces: handle the GIT_NAMESPACE
environment variable and --namespace option, and support iterating over
refs in a namespace.
Signed-off-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Jamey Sharp <jamey@minilop.net>
---
cache.h | 3 ++
contrib/completion/git-completion.bash | 1 +
environment.c | 41 ++++++++++++++++++++++++++++++++
git.c | 18 ++++++++++++-
refs.c | 25 +++++++++++++++++++
refs.h | 3 ++
6 files changed, 89 insertions(+), 2 deletions(-)
diff --git a/cache.h b/cache.h
index bc9e5eb..dc29ef3 100644
--- a/cache.h
+++ b/cache.h
@@ -380,6 +380,7 @@ static inline enum object_type object_type(unsigned int mode)
}
#define GIT_DIR_ENVIRONMENT "GIT_DIR"
+#define GIT_NAMESPACE_ENVIRONMENT "GIT_NAMESPACE"
#define GIT_WORK_TREE_ENVIRONMENT "GIT_WORK_TREE"
#define DEFAULT_GIT_DIR_ENVIRONMENT ".git"
#define DB_ENVIRONMENT "GIT_OBJECT_DIRECTORY"
@@ -420,6 +421,8 @@ extern char *get_object_directory(void);
extern char *get_index_file(void);
extern char *get_graft_file(void);
extern int set_git_dir(const char *path);
+extern const char *get_git_namespace(void);
+extern const char *strip_namespace(const char *namespaced_ref);
extern const char *get_git_work_tree(void);
extern const char *read_gitfile_gently(const char *path);
extern void set_git_work_tree(const char *tree);
diff --git a/contrib/completion/git-completion.bash b/contrib/completion/git-completion.bash
index 5a83090..e0b936d 100755
--- a/contrib/completion/git-completion.bash
+++ b/contrib/completion/git-completion.bash
@@ -2640,6 +2640,7 @@ _git ()
--exec-path
--html-path
--work-tree=
+ --namespace=
--help
"
;;
diff --git a/environment.c b/environment.c
index 94d58fd..aad274b 100644
--- a/environment.c
+++ b/environment.c
@@ -8,6 +8,7 @@
* are.
*/
#include "cache.h"
+#include "refs.h"
char git_default_email[MAX_GITNAME];
char git_default_name[MAX_GITNAME];
@@ -65,6 +66,9 @@ int core_preload_index = 0;
char *git_work_tree_cfg;
static char *work_tree;
+static const char *namespace;
+static size_t namespace_len;
+
static const char *git_dir;
static char *git_object_dir, *git_index_file, *git_graft_file;
@@ -86,6 +90,27 @@ const char * const local_repo_env[LOCAL_REPO_ENV_SIZE + 1] = {
NULL
};
+static char *expand_namespace(const char *raw_namespace)
+{
+ struct strbuf buf = STRBUF_INIT;
+ struct strbuf **components, **c;
+
+ if (!raw_namespace || !*raw_namespace)
+ return xstrdup("");
+
+ strbuf_addstr(&buf, raw_namespace);
+ components = strbuf_split(&buf, '/');
+ strbuf_reset(&buf);
+ for (c = components; *c; c++)
+ if (strcmp((*c)->buf, "/") != 0)
+ strbuf_addf(&buf, "refs/namespaces/%s", (*c)->buf);
+ strbuf_list_free(components);
+ if (check_ref_format(buf.buf) != CHECK_REF_FORMAT_OK)
+ die("bad git namespace path \"%s\"", raw_namespace);
+ strbuf_addch(&buf, '/');
+ return strbuf_detach(&buf, NULL);
+}
+
static void setup_git_env(void)
{
git_dir = getenv(GIT_DIR_ENVIRONMENT);
@@ -111,6 +136,8 @@ static void setup_git_env(void)
git_graft_file = git_pathdup("info/grafts");
if (getenv(NO_REPLACE_OBJECTS_ENVIRONMENT))
read_replace_refs = 0;
+ namespace = expand_namespace(getenv(GIT_NAMESPACE_ENVIRONMENT));
+ namespace_len = strlen(namespace);
}
int is_bare_repository(void)
@@ -131,6 +158,20 @@ const char *get_git_dir(void)
return git_dir;
}
+const char *get_git_namespace(void)
+{
+ if (!namespace)
+ setup_git_env();
+ return namespace;
+}
+
+const char *strip_namespace(const char *namespaced_ref)
+{
+ if (prefixcmp(namespaced_ref, get_git_namespace()) != 0)
+ return NULL;
+ return namespaced_ref + namespace_len;
+}
+
static int git_work_tree_initialized;
/*
diff --git a/git.c b/git.c
index 8828c18..304522b 100644
--- a/git.c
+++ b/git.c
@@ -7,8 +7,8 @@
const char git_usage_string[] =
"git [--version] [--exec-path[=<path>]] [--html-path] [--man-path] [--info-path]\n"
- " [-p|--paginate|--no-pager] [--no-replace-objects]\n"
- " [--bare] [--git-dir=<path>] [--work-tree=<path>]\n"
+ " [-p|--paginate|--no-pager] [--no-replace-objects] [--bare]\n"
+ " [--git-dir=<path>] [--work-tree=<path>] [--namespace=<name>]\n"
" [-c name=value] [--help]\n"
" <command> [<args>]";
@@ -126,6 +126,20 @@ static int handle_options(const char ***argv, int *argc, int *envchanged)
setenv(GIT_DIR_ENVIRONMENT, cmd + 10, 1);
if (envchanged)
*envchanged = 1;
+ } else if (!strcmp(cmd, "--namespace")) {
+ if (*argc < 2) {
+ fprintf(stderr, "No namespace given for --namespace.\n" );
+ usage(git_usage_string);
+ }
+ setenv(GIT_NAMESPACE_ENVIRONMENT, (*argv)[1], 1);
+ if (envchanged)
+ *envchanged = 1;
+ (*argv)++;
+ (*argc)--;
+ } else if (!prefixcmp(cmd, "--namespace=")) {
+ setenv(GIT_NAMESPACE_ENVIRONMENT, cmd + 12, 1);
+ if (envchanged)
+ *envchanged = 1;
} else if (!strcmp(cmd, "--work-tree")) {
if (*argc < 2) {
fprintf(stderr, "No directory given for --work-tree.\n" );
diff --git a/refs.c b/refs.c
index 8bf8bb6..6f313a9 100644
--- a/refs.c
+++ b/refs.c
@@ -782,6 +782,31 @@ int for_each_replace_ref(each_ref_fn fn, void *cb_data)
return do_for_each_ref(NULL, "refs/replace/", fn, 13, 0, cb_data);
}
+int head_ref_namespaced(each_ref_fn fn, void *cb_data)
+{
+ struct strbuf buf = STRBUF_INIT;
+ int ret = 0;
+ unsigned char sha1[20];
+ int flag;
+
+ strbuf_addf(&buf, "%sHEAD", get_git_namespace());
+ if (resolve_ref(buf.buf, sha1, 1, &flag))
+ ret = fn(buf.buf, sha1, flag, cb_data);
+ strbuf_release(&buf);
+
+ return ret;
+}
+
+int for_each_namespaced_ref(each_ref_fn fn, void *cb_data)
+{
+ struct strbuf buf = STRBUF_INIT;
+ int ret;
+ strbuf_addf(&buf, "%srefs/", get_git_namespace());
+ ret = do_for_each_ref(NULL, buf.buf, fn, 0, 0, cb_data);
+ strbuf_release(&buf);
+ return ret;
+}
+
int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
const char *prefix, void *cb_data)
{
diff --git a/refs.h b/refs.h
index 5de06e5..dfb086e 100644
--- a/refs.h
+++ b/refs.h
@@ -36,6 +36,9 @@ extern int for_each_tag_ref_submodule(const char *submodule, each_ref_fn fn, voi
extern int for_each_branch_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data);
extern int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data);
+extern int head_ref_namespaced(each_ref_fn fn, void *cb_data);
+extern int for_each_namespaced_ref(each_ref_fn fn, void *cb_data);
+
static inline const char *has_glob_specials(const char *pattern)
{
return strpbrk(pattern, "?*[");
--
1.7.5.4
^ permalink raw reply related [flat|nested] 7+ messages in thread* [PATCHv9 3/4] ref namespaces: Support remote repositories via upload-pack and receive-pack
2011-07-05 17:54 [PATCHv9 0/4] ref namespaces Josh Triplett
2011-07-05 17:54 ` [PATCHv9 1/4] Fix prefix handling in ref iteration functions Josh Triplett
2011-07-05 17:54 ` [PATCHv9 2/4] ref namespaces: infrastructure Josh Triplett
@ 2011-07-05 17:55 ` Josh Triplett
2011-07-06 18:55 ` Junio C Hamano
2011-07-05 17:55 ` [PATCHv9 4/4] ref namespaces: documentation Josh Triplett
3 siblings, 1 reply; 7+ messages in thread
From: Josh Triplett @ 2011-07-05 17:55 UTC (permalink / raw)
To: Junio C Hamano
Cc: Jamey Sharp, Shawn O. Pearce, Johannes Schindelin, Jeff King,
Jakub Narebski, Bert Wesarg, git
Change upload-pack and receive-pack to use the namespace-prefixed refs
when working with the repository, and use the unprefixed refs when
talking to the client, maintaining the masquerade. This allows
clone, pull, fetch, and push to work with a suitably configured
GIT_NAMESPACE.
With appropriate configuration, this also allows http-backend to expose
namespaces as multiple repositories with different paths. This only
requires setting GIT_NAMESPACE, which http-backend passes through to
upload-pack and receive-pack.
Signed-off-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Jamey Sharp <jamey@minilop.net>
---
builtin/receive-pack.c | 37 +++++++++++++++++++++++++++++++------
upload-pack.c | 15 ++++++++-------
2 files changed, 39 insertions(+), 13 deletions(-)
diff --git a/builtin/receive-pack.c b/builtin/receive-pack.c
index e1a687a..2d36378 100644
--- a/builtin/receive-pack.c
+++ b/builtin/receive-pack.c
@@ -120,9 +120,17 @@ static int show_ref(const char *path, const unsigned char *sha1, int flag, void
return 0;
}
+static int show_ref_cb(const char *path, const unsigned char *sha1, int flag, void *cb_data)
+{
+ path = strip_namespace(path);
+ if (!path)
+ path = ".have";
+ return show_ref(path, sha1, flag, cb_data);
+}
+
static void write_head_info(void)
{
- for_each_ref(show_ref, NULL);
+ for_each_ref(show_ref_cb, NULL);
if (!sent_capabilities)
show_ref("capabilities^{}", null_sha1, 0, NULL);
@@ -333,6 +341,8 @@ static void refuse_unconfigured_deny_delete_current(void)
static const char *update(struct command *cmd)
{
const char *name = cmd->ref_name;
+ struct strbuf namespaced_name_buf = STRBUF_INIT;
+ const char *namespaced_name;
unsigned char *old_sha1 = cmd->old_sha1;
unsigned char *new_sha1 = cmd->new_sha1;
struct ref_lock *lock;
@@ -343,7 +353,10 @@ static const char *update(struct command *cmd)
return "funny refname";
}
- if (is_ref_checked_out(name)) {
+ strbuf_addf(&namespaced_name_buf, "%s%s", get_git_namespace(), name);
+ namespaced_name = strbuf_detach(&namespaced_name_buf, NULL);
+
+ if (is_ref_checked_out(namespaced_name)) {
switch (deny_current_branch) {
case DENY_IGNORE:
break;
@@ -371,7 +384,7 @@ static const char *update(struct command *cmd)
return "deletion prohibited";
}
- if (!strcmp(name, head_name)) {
+ if (!strcmp(namespaced_name, head_name)) {
switch (deny_delete_current) {
case DENY_IGNORE:
break;
@@ -427,14 +440,14 @@ static const char *update(struct command *cmd)
rp_warning("Allowing deletion of corrupt ref.");
old_sha1 = NULL;
}
- if (delete_ref(name, old_sha1, 0)) {
+ if (delete_ref(namespaced_name, old_sha1, 0)) {
rp_error("failed to delete %s", name);
return "failed to delete";
}
return NULL; /* good */
}
else {
- lock = lock_any_ref_for_update(name, old_sha1, 0);
+ lock = lock_any_ref_for_update(namespaced_name, old_sha1, 0);
if (!lock) {
rp_error("failed to lock %s", name);
return "failed to lock";
@@ -491,17 +504,29 @@ static void run_update_post_hook(struct command *commands)
static void check_aliased_update(struct command *cmd, struct string_list *list)
{
+ struct strbuf buf = STRBUF_INIT;
+ const char *dst_name;
struct string_list_item *item;
struct command *dst_cmd;
unsigned char sha1[20];
char cmd_oldh[41], cmd_newh[41], dst_oldh[41], dst_newh[41];
int flag;
- const char *dst_name = resolve_ref(cmd->ref_name, sha1, 0, &flag);
+ strbuf_addf(&buf, "%s%s", get_git_namespace(), cmd->ref_name);
+ dst_name = resolve_ref(buf.buf, sha1, 0, &flag);
+ strbuf_release(&buf);
if (!(flag & REF_ISSYMREF))
return;
+ dst_name = strip_namespace(dst_name);
+ if (!dst_name) {
+ rp_error("refusing update to broken symref '%s'", cmd->ref_name);
+ cmd->skip_update = 1;
+ cmd->error_string = "broken symref";
+ return;
+ }
+
if ((item = string_list_lookup(list, dst_name)) == NULL)
return;
diff --git a/upload-pack.c b/upload-pack.c
index ce5cbbe..267e5b1 100644
--- a/upload-pack.c
+++ b/upload-pack.c
@@ -641,16 +641,17 @@ static int send_ref(const char *refname, const unsigned char *sha1, int flag, vo
" side-band-64k ofs-delta shallow no-progress"
" include-tag multi_ack_detailed";
struct object *o = parse_object(sha1);
+ const char *refname_nons = strip_namespace(refname);
if (!o)
die("git upload-pack: cannot find object %s:", sha1_to_hex(sha1));
if (capabilities)
- packet_write(1, "%s %s%c%s%s\n", sha1_to_hex(sha1), refname,
+ packet_write(1, "%s %s%c%s%s\n", sha1_to_hex(sha1), refname_nons,
0, capabilities,
stateless_rpc ? " no-done" : "");
else
- packet_write(1, "%s %s\n", sha1_to_hex(sha1), refname);
+ packet_write(1, "%s %s\n", sha1_to_hex(sha1), refname_nons);
capabilities = NULL;
if (!(o->flags & OUR_REF)) {
o->flags |= OUR_REF;
@@ -659,7 +660,7 @@ static int send_ref(const char *refname, const unsigned char *sha1, int flag, vo
if (o->type == OBJ_TAG) {
o = deref_tag(o, refname, 0);
if (o)
- packet_write(1, "%s %s^{}\n", sha1_to_hex(o->sha1), refname);
+ packet_write(1, "%s %s^{}\n", sha1_to_hex(o->sha1), refname_nons);
}
return 0;
}
@@ -680,12 +681,12 @@ static void upload_pack(void)
{
if (advertise_refs || !stateless_rpc) {
reset_timeout();
- head_ref(send_ref, NULL);
- for_each_ref(send_ref, NULL);
+ head_ref_namespaced(send_ref, NULL);
+ for_each_namespaced_ref(send_ref, NULL);
packet_flush(1);
} else {
- head_ref(mark_our_ref, NULL);
- for_each_ref(mark_our_ref, NULL);
+ head_ref_namespaced(mark_our_ref, NULL);
+ for_each_namespaced_ref(mark_our_ref, NULL);
}
if (advertise_refs)
return;
--
1.7.5.4
^ permalink raw reply related [flat|nested] 7+ messages in thread* Re: [PATCHv9 3/4] ref namespaces: Support remote repositories via upload-pack and receive-pack
2011-07-05 17:55 ` [PATCHv9 3/4] ref namespaces: Support remote repositories via upload-pack and receive-pack Josh Triplett
@ 2011-07-06 18:55 ` Junio C Hamano
2011-07-07 5:31 ` Josh Triplett
0 siblings, 1 reply; 7+ messages in thread
From: Junio C Hamano @ 2011-07-06 18:55 UTC (permalink / raw)
To: Josh Triplett
Cc: Jamey Sharp, Shawn O. Pearce, Johannes Schindelin, Jeff King,
Jakub Narebski, Bert Wesarg, git
Josh Triplett <josh@joshtriplett.org> writes:
> Change upload-pack and receive-pack to use the namespace-prefixed refs
> when working with the repository, and use the unprefixed refs when
> talking to the client, maintaining the masquerade. This allows
> clone, pull, fetch, and push to work with a suitably configured
> GIT_NAMESPACE.
>
> With appropriate configuration, this also allows http-backend to expose
> namespaces as multiple repositories with different paths. This only
> requires setting GIT_NAMESPACE, which http-backend passes through to
> upload-pack and receive-pack.
>
> Signed-off-by: Josh Triplett <josh@joshtriplett.org>
> Signed-off-by: Jamey Sharp <jamey@minilop.net>
> ---
> builtin/receive-pack.c | 37 +++++++++++++++++++++++++++++++------
> upload-pack.c | 15 ++++++++-------
> 2 files changed, 39 insertions(+), 13 deletions(-)
>
> diff --git a/builtin/receive-pack.c b/builtin/receive-pack.c
> index e1a687a..2d36378 100644
> --- a/builtin/receive-pack.c
> +++ b/builtin/receive-pack.c
> @@ -120,9 +120,17 @@ static int show_ref(const char *path, const unsigned char *sha1, int flag, void
> return 0;
> }
>
> +static int show_ref_cb(const char *path, const unsigned char *sha1, int flag, void *cb_data)
> +{
> + path = strip_namespace(path);
> + if (!path)
> + path = ".have";
> + return show_ref(path, sha1, flag, cb_data);
At the first glance, this felt somewhat unoptimal as it forbids us from
stuffing fake "ref" entries other than ".have" via the add_extra_ref()
interface, and I wondered if it would make sense to do something like this
instead:
const char *ns_path = strip_namespace(path);
if (!ns_path)
ns_path = path;
return show_ref(ns_path, sha1, flag, cb_data);
But that is flawed, and I think your patch does the right thing. The
justification is a bit subtle [*1*] and I think it needs to be explained
in a comment around here, not just in the 0/4 cover letter message.
Thanks.
[Footnote]
*1* If this callback was called for a genuine ".have" that is there only
to tell the other side that the history leading to the commit needs not to
be sent to us, we want to send it as ".have". On the other hand, if this
callback were called for a real ref that is outside the current scope, we
want to tell the other side that it is not something they can update but
we still also want to tell the other side that the history leading to the
commit needs not to be sent to us. It is the _right_ thing to do to
demotes refs outside the current scope as something that the pusher can
use to reduce network traffic yet something that the cannot update by
using the existing ".have" mechanism.
^ permalink raw reply [flat|nested] 7+ messages in thread* Re: [PATCHv9 3/4] ref namespaces: Support remote repositories via upload-pack and receive-pack
2011-07-06 18:55 ` Junio C Hamano
@ 2011-07-07 5:31 ` Josh Triplett
0 siblings, 0 replies; 7+ messages in thread
From: Josh Triplett @ 2011-07-07 5:31 UTC (permalink / raw)
To: Junio C Hamano
Cc: Jamey Sharp, Shawn O. Pearce, Johannes Schindelin, Jeff King,
Jakub Narebski, Bert Wesarg, git
On Wed, Jul 06, 2011 at 11:55:36AM -0700, Junio C Hamano wrote:
> Josh Triplett <josh@joshtriplett.org> writes:
>
> > Change upload-pack and receive-pack to use the namespace-prefixed refs
> > when working with the repository, and use the unprefixed refs when
> > talking to the client, maintaining the masquerade. This allows
> > clone, pull, fetch, and push to work with a suitably configured
> > GIT_NAMESPACE.
> >
> > With appropriate configuration, this also allows http-backend to expose
> > namespaces as multiple repositories with different paths. This only
> > requires setting GIT_NAMESPACE, which http-backend passes through to
> > upload-pack and receive-pack.
> >
> > Signed-off-by: Josh Triplett <josh@joshtriplett.org>
> > Signed-off-by: Jamey Sharp <jamey@minilop.net>
> > ---
> > builtin/receive-pack.c | 37 +++++++++++++++++++++++++++++++------
> > upload-pack.c | 15 ++++++++-------
> > 2 files changed, 39 insertions(+), 13 deletions(-)
> >
> > diff --git a/builtin/receive-pack.c b/builtin/receive-pack.c
> > index e1a687a..2d36378 100644
> > --- a/builtin/receive-pack.c
> > +++ b/builtin/receive-pack.c
> > @@ -120,9 +120,17 @@ static int show_ref(const char *path, const unsigned char *sha1, int flag, void
> > return 0;
> > }
> >
> > +static int show_ref_cb(const char *path, const unsigned char *sha1, int flag, void *cb_data)
> > +{
> > + path = strip_namespace(path);
> > + if (!path)
> > + path = ".have";
> > + return show_ref(path, sha1, flag, cb_data);
>
> At the first glance, this felt somewhat unoptimal as it forbids us from
> stuffing fake "ref" entries other than ".have" via the add_extra_ref()
> interface, and I wondered if it would make sense to do something like this
> instead:
>
> const char *ns_path = strip_namespace(path);
> if (!ns_path)
> ns_path = path;
> return show_ref(ns_path, sha1, flag, cb_data);
>
> But that is flawed, and I think your patch does the right thing. The
> justification is a bit subtle [*1*] and I think it needs to be explained
> in a comment around here, not just in the 0/4 cover letter message.
Will do. How does the following coment sound?
/* We advertise refs outside our current namespace as .have refs, so
* that the client can use them to minimize data transfer but will
* otherwise ignore them. */
- Josh Triplett
^ permalink raw reply [flat|nested] 7+ messages in thread
* [PATCHv9 4/4] ref namespaces: documentation
2011-07-05 17:54 [PATCHv9 0/4] ref namespaces Josh Triplett
` (2 preceding siblings ...)
2011-07-05 17:55 ` [PATCHv9 3/4] ref namespaces: Support remote repositories via upload-pack and receive-pack Josh Triplett
@ 2011-07-05 17:55 ` Josh Triplett
3 siblings, 0 replies; 7+ messages in thread
From: Josh Triplett @ 2011-07-05 17:55 UTC (permalink / raw)
To: Junio C Hamano
Cc: Jamey Sharp, Shawn O. Pearce, Johannes Schindelin, Jeff King,
Jakub Narebski, Bert Wesarg, git
Document the namespace mechanism in a new gitnamespaces(7) page.
Reference it from receive-pack and upload-pack.
Document the new --namespace option and GIT_NAMESPACE environment
variable in git(1), and reference gitnamespaces(7).
Add a sample Apache configuration to http-backend(1) to support
namespaced repositories, and reference gitnamespaces(7).
Signed-off-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Jamey Sharp <jamey@minilop.net>
---
Documentation/Makefile | 2 +-
Documentation/git-http-backend.txt | 8 +++
Documentation/git-receive-pack.txt | 2 +-
Documentation/git-upload-pack.txt | 4 ++
Documentation/git.txt | 13 +++++-
Documentation/gitnamespaces.txt | 75 ++++++++++++++++++++++++++++++++
contrib/completion/git-completion.bash | 2 +-
7 files changed, 101 insertions(+), 5 deletions(-)
create mode 100644 Documentation/gitnamespaces.txt
diff --git a/Documentation/Makefile b/Documentation/Makefile
index 36989b7..2004fbe 100644
--- a/Documentation/Makefile
+++ b/Documentation/Makefile
@@ -6,7 +6,7 @@ MAN5_TXT=gitattributes.txt gitignore.txt gitmodules.txt githooks.txt \
gitrepository-layout.txt
MAN7_TXT=gitcli.txt gittutorial.txt gittutorial-2.txt \
gitcvs-migration.txt gitcore-tutorial.txt gitglossary.txt \
- gitdiffcore.txt gitrevisions.txt gitworkflows.txt
+ gitdiffcore.txt gitnamespaces.txt gitrevisions.txt gitworkflows.txt
MAN_TXT = $(MAN1_TXT) $(MAN5_TXT) $(MAN7_TXT)
MAN_XML=$(patsubst %.txt,%.xml,$(MAN_TXT))
diff --git a/Documentation/git-http-backend.txt b/Documentation/git-http-backend.txt
index 277d9e1..f4e0741 100644
--- a/Documentation/git-http-backend.txt
+++ b/Documentation/git-http-backend.txt
@@ -119,6 +119,14 @@ ScriptAliasMatch \
ScriptAlias /git/ /var/www/cgi-bin/gitweb.cgi/
----------------------------------------------------------------
++
+To serve multiple repositories from different linkgit:gitnamespaces[7] in a
+single repository:
++
+----------------------------------------------------------------
+SetEnvIf Request_URI "^/git/([^/]*)" GIT_NAMESPACE=$1
+ScriptAliasMatch ^/git/[^/]*(.*) /usr/libexec/git-core/git-http-backend/storage.git$1
+----------------------------------------------------------------
Accelerated static Apache 2.x::
Similar to the above, but Apache can be used to return static
diff --git a/Documentation/git-receive-pack.txt b/Documentation/git-receive-pack.txt
index f34e0ae..3534ba0 100644
--- a/Documentation/git-receive-pack.txt
+++ b/Documentation/git-receive-pack.txt
@@ -149,7 +149,7 @@ if the repository is packed and is served via a dumb transport.
SEE ALSO
--------
-linkgit:git-send-pack[1]
+linkgit:git-send-pack[1], linkgit:gitnamespaces[7]
GIT
---
diff --git a/Documentation/git-upload-pack.txt b/Documentation/git-upload-pack.txt
index 4c0ca9d..61a9a04 100644
--- a/Documentation/git-upload-pack.txt
+++ b/Documentation/git-upload-pack.txt
@@ -33,6 +33,10 @@ OPTIONS
<directory>::
The repository to sync from.
+SEE ALSO
+--------
+linkgit:gitnamespaces[7]
+
GIT
---
Part of the linkgit:git[1] suite
diff --git a/Documentation/git.txt b/Documentation/git.txt
index 3c7a832..81cb1c6 100644
--- a/Documentation/git.txt
+++ b/Documentation/git.txt
@@ -10,8 +10,8 @@ SYNOPSIS
--------
[verse]
'git' [--version] [--exec-path[=<path>]] [--html-path] [--man-path] [--info-path]
- [-p|--paginate|--no-pager] [--no-replace-objects]
- [--bare] [--git-dir=<path>] [--work-tree=<path>]
+ [-p|--paginate|--no-pager] [--no-replace-objects] [--bare]
+ [--git-dir=<path>] [--work-tree=<path>] [--namespace=<name>]
[-c <name>=<value>]
[--help] <command> [<args>]
@@ -330,6 +330,11 @@ help ...`.
variable (see core.worktree in linkgit:git-config[1] for a
more detailed discussion).
+--namespace=<path>::
+ Set the git namespace. See linkgit:gitnamespaces[7] for more
+ details. Equivalent to setting the `GIT_NAMESPACE` environment
+ variable.
+
--bare::
Treat the repository as a bare repository. If GIT_DIR
environment is not set, it is set to the current working
@@ -594,6 +599,10 @@ git so take care if using Cogito etc.
This can also be controlled by the '--work-tree' command line
option and the core.worktree configuration variable.
+'GIT_NAMESPACE'::
+ Set the git namespace; see linkgit:gitnamespaces[7] for details.
+ The '--namespace' command-line option also sets this value.
+
'GIT_CEILING_DIRECTORIES'::
This should be a colon-separated list of absolute paths.
If set, it is a list of directories that git should not chdir
diff --git a/Documentation/gitnamespaces.txt b/Documentation/gitnamespaces.txt
new file mode 100644
index 0000000..ed8924e
--- /dev/null
+++ b/Documentation/gitnamespaces.txt
@@ -0,0 +1,75 @@
+gitnamespaces(7)
+================
+
+NAME
+----
+gitnamespaces - Git namespaces
+
+DESCRIPTION
+-----------
+
+Git supports dividing the refs of a single repository into multiple
+namespaces, each of which has its own branches, tags, and HEAD. Git can
+expose each namespace as an independent repository to pull from and push
+to, while sharing the object store, and exposing all the refs to
+operations such as linkgit:git-gc[1].
+
+Storing multiple repositories as namespaces of a single repository
+avoids storing duplicate copies of the same objects, such as when
+storing multiple branches of the same source. The alternates mechanism
+provides similar support for avoiding duplicates, but alternates do not
+prevent duplication between new objects added to the repositories
+without ongoing maintenance, while namespaces do.
+
+To specify a namespace, set the `GIT_NAMESPACE` environment variable to
+the namespace. For each ref namespace, git stores the corresponding
+refs in a directory under `refs/namespaces/`. For example,
+`GIT_NAMESPACE=foo` will store refs under `refs/namespaces/foo/`. You
+can also specify namespaces via the `--namespace` option to
+linkgit:git[1].
+
+Note that namespaces which include a `/` will expand to a hierarchy of
+namespaces; for example, `GIT_NAMESPACE=foo/bar` will store refs under
+`refs/namespaces/foo/refs/namespaces/bar/`. This makes paths in
+`GIT_NAMESPACE` behave hierarchically, so that cloning with
+`GIT_NAMESPACE=foo/bar` produces the same result as cloning with
+`GIT_NAMESPACE=foo` and cloning from that repo with `GIT_NAMESPACE=bar`. It
+also avoids ambiguity with strange namespace paths such as `foo/refs/heads/`,
+which could otherwise generate directory/file conflicts within the `refs`
+directory.
+
+linkgit:git-upload-pack[1] and linkgit:git-receive-pack[1] rewrite the
+names of refs as specified by `GIT_NAMESPACE`. git-upload-pack and
+git-receive-pack will ignore all references outside the specified
+namespace.
+
+The smart HTTP server, linkgit:git-http-backend[1], will pass
+GIT_NAMESPACE through to the backend programs; see
+linkgit:git-http-backend[1] for sample configuration to expose
+repository namespaces as repositories.
+
+For a simple local test, you can use linkgit:git-remote-ext[1]:
+
+----------
+git clone ext::'git --namespace=foo %s /tmp/prefixed.git'
+----------
+
+SECURITY
+--------
+
+Anyone with access to any namespace within a repository can potentially
+access objects from any other namespace stored in the same repository.
+You can't directly say "give me object ABCD" if you don't have a ref to
+it, but you can do some other sneaky things like:
+
+. Claiming to push ABCD, at which point the server will optimize out the
+ need for you to actually send it. Now you have a ref to ABCD and can
+ fetch it (claiming not to have it, of course).
+
+. Requesting other refs, claiming that you have ABCD, at which point the
+ server may generate deltas against ABCD.
+
+None of this causes a problem if you only host public repositories, or
+if everyone who may read one namespace may also read everything in every
+other namespace (for instance, if everyone in an organization has read
+permission to every repository).
diff --git a/contrib/completion/git-completion.bash b/contrib/completion/git-completion.bash
index e0b936d..8648a36 100755
--- a/contrib/completion/git-completion.bash
+++ b/contrib/completion/git-completion.bash
@@ -1469,7 +1469,7 @@ _git_help ()
__gitcomp "$__git_all_commands $(__git_aliases)
attributes cli core-tutorial cvs-migration
diffcore gitk glossary hooks ignore modules
- repository-layout tutorial tutorial-2
+ namespaces repository-layout tutorial tutorial-2
workflows
"
}
--
1.7.5.4
^ permalink raw reply related [flat|nested] 7+ messages in thread