Add support for url aliases in config files
authorDaniel Barkalow <barkalow@iabervon.org>
Wed, 20 Feb 2008 18:43:53 +0000 (13:43 -0500)
committerJunio C Hamano <gitster@pobox.com>
Mon, 25 Feb 2008 04:05:29 +0000 (20:05 -0800)
This allows users with different preferences for access methods to the
same remote repositories to rewrite each other's URLs by pattern
matching across a large set of similiarly set up repositories to each
get the desired access.

For example, if you don't have a kernel.org account, you might want
settings like:

[url "git://git.kernel.org/pub/"]
      insteadOf = master.kernel.org:/pub

Then, if you give git a URL like:

  master.kernel.org:/pub/scm/linux/kernel/git/linville/wireless-2.6.git

it will act like you gave it:

  git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless-2.6.git

and you can cut-and-paste pull requests in email without fixing them
by hand, for example.

Signed-off-by: Daniel Barkalow <barkalow@iabervon.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Documentation/config.txt
Documentation/urls.txt
remote.c
t/t5516-fetch-push.sh

index f2f6a774e044e03e78d83e4e77aedcff122f5688..298138917a3eb5a0f75ff11a09d286efef3d45b5 100644 (file)
@@ -886,6 +886,18 @@ tar.umask::
        archiving user's umask will be used instead.  See umask(2) and
        linkgit:git-archive[1].
 
+url.<base>.insteadOf::
+       Any URL that starts with this value will be rewritten to
+       start, instead, with <base>. In cases where some site serves a
+       large number of repositories, and serves them with multiple
+       access methods, and some users need to use different access
+       methods, this feature allows people to specify any of the
+       equivalent URLs and have git automatically rewrite the URL to
+       the best alternative for the particular user, even for a
+       never-before-seen repository on the site. The effect of
+       having multiple `insteadOf` values from different
+       `<base>` match to an URL is undefined.
+
 user.email::
        Your email address to be recorded in any newly created commits.
        Can be overridden by the 'GIT_AUTHOR_EMAIL', 'GIT_COMMITTER_EMAIL', and
index 81ac17f32a0587e3d2d41eb8ee89dd85e13f1802..fa34c6747194aaecf9e8124462129b8bbc9ae7d4 100644 (file)
@@ -44,3 +44,26 @@ endif::git-clone[]
 ifdef::git-clone[]
 They are equivalent, except the former implies --local option.
 endif::git-clone[]
+
+
+If there are a large number of similarly-named remote repositories and
+you want to use a different format for them (such that the URLs you
+use will be rewritten into URLs that work), you can create a
+configuration section of the form:
+
+------------
+       [url "<actual url base>"]
+               insteadOf = <other url base>
+------------
+
+For example, with this:
+
+------------
+       [url "git://git.host.xz/"]
+               insteadOf = host.xz:/path/to/
+               insteadOf = work:
+------------
+
+a URL like "work:repo.git" or like "host.xz:/path/to/repo.git" will be
+rewritten in any context that takes a URL to be "git://git.host.xz/repo.git".
+
index 457d8a44c70347adbadba994de32770812ec7c57..0012954b6f795d75d442f4c58f29dc194888d022 100644 (file)
--- a/remote.c
+++ b/remote.c
@@ -2,6 +2,13 @@
 #include "remote.h"
 #include "refs.h"
 
+struct rewrite {
+       const char *base;
+       const char **instead_of;
+       int instead_of_nr;
+       int instead_of_alloc;
+};
+
 static struct remote **remotes;
 static int remotes_alloc;
 static int remotes_nr;
@@ -13,9 +20,33 @@ static int branches_nr;
 static struct branch *current_branch;
 static const char *default_remote_name;
 
+static struct rewrite **rewrite;
+static int rewrite_alloc;
+static int rewrite_nr;
+
 #define BUF_SIZE (2048)
 static char buffer[BUF_SIZE];
 
+static const char *alias_url(const char *url)
+{
+       int i, j;
+       for (i = 0; i < rewrite_nr; i++) {
+               if (!rewrite[i])
+                       continue;
+               for (j = 0; j < rewrite[i]->instead_of_nr; j++) {
+                       if (!prefixcmp(url, rewrite[i]->instead_of[j])) {
+                               char *ret = malloc(strlen(rewrite[i]->base) -
+                                                  strlen(rewrite[i]->instead_of[j]) +
+                                                  strlen(url) + 1);
+                               strcpy(ret, rewrite[i]->base);
+                               strcat(ret, url + strlen(rewrite[i]->instead_of[j]));
+                               return ret;
+                       }
+               }
+       }
+       return url;
+}
+
 static void add_push_refspec(struct remote *remote, const char *ref)
 {
        ALLOC_GROW(remote->push_refspec,
@@ -38,6 +69,11 @@ static void add_url(struct remote *remote, const char *url)
        remote->url[remote->url_nr++] = url;
 }
 
+static void add_url_alias(struct remote *remote, const char *url)
+{
+       add_url(remote, alias_url(url));
+}
+
 static struct remote *make_remote(const char *name, int len)
 {
        struct remote *ret;
@@ -95,6 +131,35 @@ static struct branch *make_branch(const char *name, int len)
        return ret;
 }
 
+static struct rewrite *make_rewrite(const char *base, int len)
+{
+       struct rewrite *ret;
+       int i;
+
+       for (i = 0; i < rewrite_nr; i++) {
+               if (len ? (!strncmp(base, rewrite[i]->base, len) &&
+                          !rewrite[i]->base[len]) :
+                   !strcmp(base, rewrite[i]->base))
+                       return rewrite[i];
+       }
+
+       ALLOC_GROW(rewrite, rewrite_nr + 1, rewrite_alloc);
+       ret = xcalloc(1, sizeof(struct rewrite));
+       rewrite[rewrite_nr++] = ret;
+       if (len)
+               ret->base = xstrndup(base, len);
+       else
+               ret->base = xstrdup(base);
+
+       return ret;
+}
+
+static void add_instead_of(struct rewrite *rewrite, const char *instead_of)
+{
+       ALLOC_GROW(rewrite->instead_of, rewrite->instead_of_nr + 1, rewrite->instead_of_alloc);
+       rewrite->instead_of[rewrite->instead_of_nr++] = instead_of;
+}
+
 static void read_remotes_file(struct remote *remote)
 {
        FILE *f = fopen(git_path("remotes/%s", remote->name), "r");
@@ -128,7 +193,7 @@ static void read_remotes_file(struct remote *remote)
 
                switch (value_list) {
                case 0:
-                       add_url(remote, xstrdup(s));
+                       add_url_alias(remote, xstrdup(s));
                        break;
                case 1:
                        add_push_refspec(remote, xstrdup(s));
@@ -180,7 +245,7 @@ static void read_branches_file(struct remote *remote)
        } else {
                branch = "refs/heads/master";
        }
-       add_url(remote, p);
+       add_url_alias(remote, p);
        add_fetch_refspec(remote, branch);
        remote->fetch_tags = 1; /* always auto-follow */
 }
@@ -210,6 +275,19 @@ static int handle_config(const char *key, const char *value)
                }
                return 0;
        }
+       if (!prefixcmp(key, "url.")) {
+               struct rewrite *rewrite;
+               name = key + 5;
+               subkey = strrchr(name, '.');
+               if (!subkey)
+                       return 0;
+               rewrite = make_rewrite(name, subkey - name);
+               if (!strcmp(subkey, ".insteadof")) {
+                       if (!value)
+                               return config_error_nonbool(key);
+                       add_instead_of(rewrite, xstrdup(value));
+               }
+       }
        if (prefixcmp(key,  "remote."))
                return 0;
        name = key + 7;
@@ -261,6 +339,18 @@ static int handle_config(const char *key, const char *value)
        return 0;
 }
 
+static void alias_all_urls(void)
+{
+       int i, j;
+       for (i = 0; i < remotes_nr; i++) {
+               if (!remotes[i])
+                       continue;
+               for (j = 0; j < remotes[i]->url_nr; j++) {
+                       remotes[i]->url[j] = alias_url(remotes[i]->url[j]);
+               }
+       }
+}
+
 static void read_config(void)
 {
        unsigned char sha1[20];
@@ -277,6 +367,7 @@ static void read_config(void)
                        make_branch(head_ref + strlen("refs/heads/"), 0);
        }
        git_config(handle_config);
+       alias_all_urls();
 }
 
 struct refspec *parse_ref_spec(int nr_refspec, const char **refspec)
@@ -342,7 +433,7 @@ struct remote *remote_get(const char *name)
                        read_branches_file(ret);
        }
        if (!ret->url)
-               add_url(ret, name);
+               add_url_alias(ret, name);
        if (!ret->url)
                return NULL;
        ret->fetch = parse_ref_spec(ret->fetch_refspec_nr, ret->fetch_refspec);
index 9d2dc33cbd0d1df19b0a9003e545104a982da694..9023ba05af6b6fc6023fe0213b6798a3d7408750 100755 (executable)
@@ -100,6 +100,23 @@ test_expect_success 'fetch with wildcard' '
        )
 '
 
+test_expect_success 'fetch with insteadOf' '
+       mk_empty &&
+       (
+               TRASH=$(pwd) &&
+               cd testrepo &&
+               git config url./$TRASH/.insteadOf trash/
+               git config remote.up.url trash/. &&
+               git config remote.up.fetch "refs/heads/*:refs/remotes/origin/*" &&
+               git fetch up &&
+
+               r=$(git show-ref -s --verify refs/remotes/origin/master) &&
+               test "z$r" = "z$the_commit" &&
+
+               test 1 = $(git for-each-ref refs/remotes/origin | wc -l)
+       )
+'
+
 test_expect_success 'push without wildcard' '
        mk_empty &&
 
@@ -126,6 +143,20 @@ test_expect_success 'push with wildcard' '
        )
 '
 
+test_expect_success 'push with insteadOf' '
+       mk_empty &&
+       TRASH=$(pwd) &&
+       git config url./$TRASH/.insteadOf trash/ &&
+       git push trash/testrepo refs/heads/master:refs/remotes/origin/master &&
+       (
+               cd testrepo &&
+               r=$(git show-ref -s --verify refs/remotes/origin/master) &&
+               test "z$r" = "z$the_commit" &&
+
+               test 1 = $(git for-each-ref refs/remotes/origin | wc -l)
+       )
+'
+
 test_expect_success 'push with matching heads' '
 
        mk_test heads/master &&