config: provide a version of git_config with more options

Callers may want to provide a specific version of a file in which to look
for config. Right now this can be done by setting the magic global
config_exclusive_filename variable.  By providing a version of git_config
that takes a filename, we can take a step towards making this magic global
go away.

Furthermore, by providing a more "advanced" interface, we now have a a
natural place to add new options for callers like git-config, which care
about tweaking the specifics of config lookup, without disturbing the
large number of "simple" users (i.e., every other part of git).

The astute reader of this patch may notice that the logic for handling
config_exclusive_filename was taken out of git_config_early, but added
into git_config. This means that git_config_early will no longer respect
config_exclusive_filename.  That's OK, because the only other caller of
git_config_early is check_repository_format_gently, but the only function
which sets config_exclusive_filename is cmd_config, which does not call
check_repository_format_gently (and if it did, it would have been a bug,
anyway, as we would be checking the repository format in the wrong file).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/Documentation/technical/api-config.txt b/Documentation/technical/api-config.txt
index 01f64d187f9ddf0538dbb475a5f69667136fd7e8..b0aeb2e481ecabdb4ce60dce4aa8efe61f06f648 100644 (file)
--- a/Documentation/technical/api-config.txt
+++ b/Documentation/technical/api-config.txt
@@ -47,6 +47,18 @@ will first feed the user-wide one to the callback, and then the
 repo-specific one; by overwriting, the higher-priority repo-specific
 value is left at the end).
 
+The `git_config_with_options` function lets the caller examine config
+while adjusting some of the default behavior of `git_config`. It should
+almost never be used by "regular" git code that is looking up
+configuration variables. It is intended for advanced callers like
+`git-config`, which are intentionally tweaking the normal config-lookup
+process. It takes one extra parameter:
+
+`filename`::
+If this parameter is non-NULL, it specifies the name of a file to
+parse for configuration, rather than looking in the usual files. Regular
+`git_config` defaults to `NULL`.
+
 There is a special version of `git_config` called `git_config_early`.
 This version takes an additional parameter to specify the repository
 config, instead of having it looked up via `git_path`. This is useful

diff --git a/cache.h b/cache.h
index 0d0c51a39411e149bc6c3ab48a8068011ff50ffa..604236a28f59f61aa3800a000ebb47ac40e09d9b 100644 (file)
--- a/cache.h
+++ b/cache.h
@@ -1113,6 +1113,7 @@ extern int git_config_from_file(config_fn_t fn, const char *, void *);
 extern void git_config_push_parameter(const char *text);
 extern int git_config_from_parameters(config_fn_t fn, void *data);
 extern int git_config(config_fn_t fn, void *);
+extern int git_config_with_options(config_fn_t fn, void *, const char *filename);
 extern int git_config_early(config_fn_t fn, void *, const char *repo_config);
 extern int git_parse_ulong(const char *, unsigned long *);
 extern int git_config_int(const char *, const char *);

diff --git a/config.c b/config.c
index bc2e23379fd6ea74368c982df12b780f512f59ba..531d4d43e7de4780eb03c6a708fc942dc2492c8e 100644 (file)
--- a/config.c
+++ b/config.c
@@ -879,9 +879,6 @@ int git_config_early(config_fn_t fn, void *data, const char *repo_config)
        int ret = 0, found = 0;
        const char *home = NULL;
 
-       /* Setting $GIT_CONFIG makes git read _only_ the given config file. */
-       if (config_exclusive_filename)
-               return git_config_from_file(fn, config_exclusive_filename, data);
        if (git_config_system() && !access(git_etc_gitconfig(), R_OK)) {
                ret += git_config_from_file(fn, git_etc_gitconfig(),
                                            data);
@@ -917,11 +914,19 @@ int git_config_early(config_fn_t fn, void *data, const char *repo_config)
        return ret == 0 ? found : ret;
 }
 
-int git_config(config_fn_t fn, void *data)
+int git_config_with_options(config_fn_t fn, void *data,
+                           const char *filename)
 {
        char *repo_config = NULL;
        int ret;
 
+       /*
+        * If we have a specific filename, use it. Otherwise, follow the
+        * regular lookup sequence.
+        */
+       if (filename)
+               return git_config_from_file(fn, filename, data);
+
        repo_config = git_pathdup("config");
        ret = git_config_early(fn, data, repo_config);
        if (repo_config)
@@ -929,6 +934,11 @@ int git_config(config_fn_t fn, void *data)
        return ret;
 }
 
+int git_config(config_fn_t fn, void *data)
+{
+       return git_config_with_options(fn, data, config_exclusive_filename);
+}
+
 /*
  * Find all the stuff for git_config_set() below.
  */