On 06/07/14 08:19, Tanay Abhra wrote: > Currently `git_config()` uses a callback mechanism and file rereads for > config values. Due to this approach, it is not uncommon for the config > files to be parsed several times during the run of a git program, with > different callbacks picking out different variables useful to themselves. > > Add a `config_set`, that can be used to construct an in-memory cache for > config-like files that the caller specifies (i.e., files like `.gitmodules`, > `~/.gitconfig` etc.). Add two external functions `git_configset_get_value` > and `git_configset_get_value_multi` for querying from the config sets. > `git_configset_get_value` follows `last one wins` semantic (i.e. if there > are multiple matches for the queried key in the files of the configset the > value returned will be the last entry in `value_list`). > `git_configset_get_value_multi` returns a list of values sorted in order of > increasing priority (i.e. last match will be at the end of the list). Add > type specific query functions like `git_configset_get_bool` and similar. > > Add a default `config_set`, `the_config_set` to cache all key-value pairs > read from usual config files (repo specific .git/config, user wide > ~/.gitconfig and the global /etc/gitconfig). `the_config_set` uses a > single hashmap populated using `git_config()`. > > Add two external functions `git_config_get_value` and > `git_config_get_value_multi` for querying in a non-callback manner from > `the_config_set`. Also, add type specific query functions that are > implemented as a thin wrapper around the `config_set` API. > > Signed-off-by: Tanay Abhra <tanayabh@xxxxxxxxx> > --- > Documentation/technical/api-config.txt | 134 +++++++++++++++ > Makefile | 1 + > cache.h | 34 ++++ > config-hash.c | 297 +++++++++++++++++++++++++++++++++ > config.c | 3 + > 5 files changed, 469 insertions(+) > create mode 100644 config-hash.c > > diff --git a/Documentation/technical/api-config.txt b/Documentation/technical/api-config.txt > index 230b3a0..bdf86d0 100644 > --- a/Documentation/technical/api-config.txt > +++ b/Documentation/technical/api-config.txt > @@ -77,6 +77,81 @@ To read a specific file in git-config format, use > `git_config_from_file`. This takes the same callback and data parameters > as `git_config`. > > +Querying For Specific Variables > +------------------------------- > + > +For programs wanting to query for specific variables in a non-callback > +manner, the config API provides two functions `git_config_get_value` > +and `git_config_get_value_multi`. They both read values from an internal > +cache generated previously from reading the config files. > + > +`int git_config_get_value(const char *key, const char **value)`:: > + > + Finds the highest-priority value for the configuration variable `key`, > + stores the pointer to it in `value` and returns 0. When the > + configuration variable `key` is not found, returns 1 without touching > + `value`. The caller should not free or modify `value`, as it is owned > + by the cache. > + > +`const struct string_list *git_config_get_value_multi(const char *key)`:: > + > + Finds and returns the value list, sorted in order of increasing priority > + for the configuration variable `key`. When the configuration variable > + `key` is not found, returns NULL. The caller should not free or modify > + the returned pointer, as it is owned by the cache. > + > +`void git_config_clear(void)`:: > + > + Resets and invalidate the config cache. > + > +The config API also provides type specific API functions which do conversion > +as well as retrieval for the queried variable, including: > + > +`int git_config_get_int(const char *key, int *dest)`:: > + > + Finds and parses the value to an integer for the configuration variable > + `key`. Dies on error; otherwise, stores pointer to the parsed integer in ... stores the value of the parsed integer in `dest` ... > + `dest` and returns 0. When the configuration variable `key` is not found, > + returns 1 without touching `dest`. > + > +`int git_config_get_ulong(const char *key, unsigned long *dest)`:: > + > + Similar to `git_config_get_int` but for unsigned longs. > + > +`int git_config_get_int(const char *key, int *dest)`:: -----------------------^^^ git_config_get_bool > + > + Finds and parses the value into a boolean value, for the configuration > + variable `key`respecting keywords like "true" and "false". Integer > + values are converted into true/false values (when they are non-zero or > + zero, respectively). Other values cause a die(). If parsing is successful, > + stores the pointer to the parsed result in `dest` and returns 0. When the ... stores the value of the parsed result in `dest` ... > + configuration variable `key` is not found, returns 1 without touching > + `dest`. > + > +`int git_config_get_bool_or_int(const char *key, int *is_bool, int *dest)`:: > + > + Similar to `git_config_get_bool`, except that integers are copied as-is, > + and `is_bool` flag is unset. > + > +`int git_config_get_maybe_bool(const char *key, int *dest)`:: > + > + Similar to `git_config_get_bool`, except that it returns -1 on error > + rather than dying. > + > +`int git_config_get_string(const char *key, const char **dest)`:: > + > + Allocates and copies the retrieved string into the `dest` parameter for > + the configuration variable `key`; if NULL string is given, prints an > + error message and returns -1. When the configuration variable `key` is > + not found, returns 1 without touching `dest`. > + > +`int git_config_get_pathname(const char *key, const char **dest)`:: > + > + Similar to `git_config_get_string`, but expands `~` or `~user` into > + the user's home directory when found at the beginning of the path. > + > +See test-config.c for usage examples. > + Sorry, I didn't have time to do more than squint at the code, but at first glance it looks good. ATB, Ramsay Jones -- To unsubscribe from this list: send the line "unsubscribe git" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html