Move the documentation from Documentation/technical/api-config.txt into config.h
Signed-off-by: Heba Waly heba.w...@gmail.com [heba.w...@gmail.com] Thanks for taking the time to contribute to Git! Please be advised that the Git community does not use github.com for their contributions. Instead, we use a mailing list (git@vger.kernel.org) for code submissions, code reviews, and bug reports. Nevertheless, you can use GitGitGadget ( https://gitgitgadget.github.io/) to conveniently send your Pull Requests commits to our mailing list. Please read the "guidelines for contributing" linked above! Heba Waly (1): config: move documentation to config.h Documentation/technical/api-config.txt | 319 ----------------------- config.h | 336 +++++++++++++++++++++++++ 2 files changed, 336 insertions(+), 319 deletions(-) delete mode 100644 Documentation/technical/api-config.txt base-commit: 108b97dc372828f0e72e56bbb40cae8e1e83ece6 Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-405%2FHebaWaly%2Fconfig_documentation-v2 Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-405/HebaWaly/config_documentation-v2 Pull-Request: https://github.com/gitgitgadget/git/pull/405 Range-diff vs v1: 1: 2e42eafb5d ! 1: 1a9aa33b46 config: add documentation to config.h @@ -1,12 +1,336 @@ Author: Heba Waly <heba.w...@gmail.com> - config: add documentation to config.h - - This commit is copying and summarizing the documentation from - documentation/technical/api-config.txt to comments in config.h + config: move documentation to config.h + Move the documentation from Documentation/technical/api-config.txt into + config.h Signed-off-by: Heba Waly <heba.w...@gmail.com> + diff --git a/Documentation/technical/api-config.txt b/Documentation/technical/api-config.txt + deleted file mode 100644 + --- a/Documentation/technical/api-config.txt + +++ /dev/null +@@ +-config API +-========== +- +-The config API gives callers a way to access Git configuration files +-(and files which have the same syntax). See linkgit:git-config[1] for a +-discussion of the config file syntax. +- +-General Usage +-------------- +- +-Config files are parsed linearly, and each variable found is passed to a +-caller-provided callback function. The callback function is responsible +-for any actions to be taken on the config option, and is free to ignore +-some options. It is not uncommon for the configuration to be parsed +-several times during the run of a Git program, with different callbacks +-picking out different variables useful to themselves. +- +-A config callback function takes three parameters: +- +-- the name of the parsed variable. This is in canonical "flat" form: the +- section, subsection, and variable segments will be separated by dots, +- and the section and variable segments will be all lowercase. E.g., +- `core.ignorecase`, `diff.SomeType.textconv`. +- +-- the value of the found variable, as a string. If the variable had no +- value specified, the value will be NULL (typically this means it +- should be interpreted as boolean true). +- +-- a void pointer passed in by the caller of the config API; this can +- contain callback-specific data +- +-A config callback should return 0 for success, or -1 if the variable +-could not be parsed properly. +- +-Basic Config Querying +---------------------- +- +-Most programs will simply want to look up variables in all config files +-that Git knows about, using the normal precedence rules. To do this, +-call `git_config` with a callback function and void data pointer. +- +-`git_config` will read all config sources in order of increasing +-priority. Thus a callback should typically overwrite previously-seen +-entries with new ones (e.g., if both the user-wide `~/.gitconfig` and +-repo-specific `.git/config` contain `color.ui`, the config machinery +-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 `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 two extra parameters: +- +-`config_source`:: +-If this parameter is non-NULL, it specifies the source to parse for +-configuration, rather than looking in the usual files. See `struct +-git_config_source` in `config.h` for details. Regular `git_config` defaults +-to `NULL`. +- +-`opts`:: +-Specify options to adjust the behavior of parsing config files. See `struct +-config_options` in `config.h` for details. As an example: regular `git_config` +-sets `opts.respect_includes` to `1` by default. +- +-Reading Specific Files +----------------------- +- +-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 invalidates 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 the value of the parsed integer in +- `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_bool(const char *key, int *dest)`:: +- +- 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 value of the parsed result in `dest` and returns 0. When the +- 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(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_string(const char *key, char **dest)`:: +- +- Similar to `git_config_get_string_const`, except that retrieved value +- copied into the `dest` parameter is a mutable string. +- +-`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. +- +-`git_die_config(const char *key, const char *err, ...)`:: +- +- First prints the error message specified by the caller in `err` and then +- dies printing the line number and the file name of the highest priority +- value for the configuration variable `key`. +- +-`void git_die_config_linenr(const char *key, const char *filename, int linenr)`:: +- +- Helper function which formats the die error message according to the +- parameters entered. Used by `git_die_config()`. It can be used by callers +- handling `git_config_get_value_multi()` to print the correct error message +- for the desired value. +- +-See test-config.c for usage examples. +- +-Value Parsing Helpers +---------------------- +- +-To aid in parsing string values, the config API provides callbacks with +-a number of helper functions, including: +- +-`git_config_int`:: +-Parse the string to an integer, including unit factors. Dies on error; +-otherwise, returns the parsed result. +- +-`git_config_ulong`:: +-Identical to `git_config_int`, but for unsigned longs. +- +-`git_config_bool`:: +-Parse a string into a boolean value, 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, the return value is the result. +- +-`git_config_bool_or_int`:: +-Same as `git_config_bool`, except that integers are returned as-is, and +-an `is_bool` flag is unset. +- +-`git_parse_maybe_bool`:: +-Same as `git_config_bool`, except that it returns -1 on error rather +-than dying. +- +-`git_config_string`:: +-Allocates and copies the value string into the `dest` parameter; if no +-string is given, prints an error message and returns -1. +- +-`git_config_pathname`:: +-Similar to `git_config_string`, but expands `~` or `~user` into the +-user's home directory when found at the beginning of the path. +- +-Include Directives +------------------- +- +-By default, the config parser does not respect include directives. +-However, a caller can use the special `git_config_include` wrapper +-callback to support them. To do so, you simply wrap your "real" callback +-function and data pointer in a `struct config_include_data`, and pass +-the wrapper to the regular config-reading functions. For example: +- +-------------------------------------------- +-int read_file_with_include(const char *file, config_fn_t fn, void *data) +-{ +- struct config_include_data inc = CONFIG_INCLUDE_INIT; +- inc.fn = fn; +- inc.data = data; +- return git_config_from_file(git_config_include, file, &inc); +-} +-------------------------------------------- +- +-`git_config` respects includes automatically. The lower-level +-`git_config_from_file` does not. +- +-Custom Configsets +------------------ +- +-A `config_set` can be used to construct an in-memory cache for +-config-like files that the caller specifies (i.e., files like `.gitmodules`, +-`~/.gitconfig` etc.). For example, +- +----------------------------------------- +-struct config_set gm_config; +-git_configset_init(&gm_config); +-int b; +-/* we add config files to the config_set */ +-git_configset_add_file(&gm_config, ".gitmodules"); +-git_configset_add_file(&gm_config, ".gitmodules_alt"); +- +-if (!git_configset_get_bool(gm_config, "submodule.frotz.ignore", &b)) { +- /* hack hack hack */ +-} +- +-/* when we are done with the configset */ +-git_configset_clear(&gm_config); +----------------------------------------- +- +-Configset API provides functions for the above mentioned work flow, including: +- +-`void git_configset_init(struct config_set *cs)`:: +- +- Initializes the config_set `cs`. +- +-`int git_configset_add_file(struct config_set *cs, const char *filename)`:: +- +- Parses the file and adds the variable-value pairs to the `config_set`, +- dies if there is an error in parsing the file. Returns 0 on success, or +- -1 if the file does not exist or is inaccessible. The user has to decide +- if he wants to free the incomplete configset or continue using it when +- the function returns -1. +- +-`int git_configset_get_value(struct config_set *cs, const char *key, const char **value)`:: +- +- Finds the highest-priority value for the configuration variable `key` +- and config set `cs`, 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_configset_get_value_multi(struct config_set *cs, const char *key)`:: +- +- Finds and returns the value list, sorted in order of increasing priority +- for the configuration variable `key` and config set `cs`. 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_configset_clear(struct config_set *cs)`:: +- +- Clears `config_set` structure, removes all saved variable-value pairs. +- +-In addition to above functions, the `config_set` API provides type specific +-functions in the vein of `git_config_get_int` and family but with an extra +-parameter, pointer to struct `config_set`. +-They all behave similarly to the `git_config_get*()` family described in +-"Querying For Specific Variables" above. +- +-Writing Config Files +--------------------- +- +-Git gives multiple entry points in the Config API to write config values to +-files namely `git_config_set_in_file` and `git_config_set`, which write to +-a specific config file or to `.git/config` respectively. They both take a +-key/value pair as parameter. +-In the end they both call `git_config_set_multivar_in_file` which takes four +-parameters: +- +-- the name of the file, as a string, to which key/value pairs will be written. +- +-- the name of key, as a string. This is in canonical "flat" form: the section, +- subsection, and variable segments will be separated by dots, and the section +- and variable segments will be all lowercase. +- E.g., `core.ignorecase`, `diff.SomeType.textconv`. +- +-- the value of the variable, as a string. If value is equal to NULL, it will +- remove the matching key from the config file. +- +-- the value regex, as a string. It will disregard key/value pairs where value +- does not match. +- +-- a multi_replace value, as an int. If value is equal to zero, nothing or only +- one matching key/value is replaced, else all matching key/values (regardless +- how many) are removed, before the new pair is written. +- +-It returns 0 on success. +- +-Also, there are functions `git_config_rename_section` and +-`git_config_rename_section_in_file` with parameters `old_name` and `new_name` +-for renaming or removing sections in the config files. If NULL is passed +-through `new_name` parameter, the section will be removed from the config file. + diff --git a/config.h b/config.h --- a/config.h +++ b/config.h @@ -29,7 +353,16 @@ + * some options. It is not uncommon for the configuration to be parsed + * several times during the run of a Git program, with different callbacks + * picking out different variables useful to themselves. -+ * ++ */ ++ + struct object_id; + + /* git_config_parse_key() returns these negated: */ +@@ + } error_action; + }; + ++/** + * A config callback function takes three parameters: + * + * - the name of the parsed variable. This is in canonical "flat" form: the @@ -47,13 +380,8 @@ + * A config callback should return 0 for success, or -1 if the variable + * could not be parsed properly. + */ -+ - struct object_id; - - /* git_config_parse_key() returns these negated: */ -@@ - typedef int (*config_fn_t)(const char *, const char *, void *); ++ int git_default_config(const char *, const char *, void *); + +/** @@ -61,8 +389,10 @@ + * This function takes the same callback and data parameters as `git_config`. + */ int git_config_from_file(config_fn_t fn, const char *, void *); ++ int git_config_from_file_with_options(config_fn_t fn, const char *, void *, + const struct config_options *); @@ int git_config_from_parameters(config_fn_t fn, void *data); void read_early_config(config_fn_t cb, void *data); @@ -91,13 +421,13 @@ + * intentionally tweaking the normal config-lookup process. + * It takes two extra parameters: + * -+ * `config_source`:: ++ * - `config_source` + * If this parameter is non-NULL, it specifies the source to parse for + * configuration, rather than looking in the usual files. See `struct + * git_config_source` in `config.h` for details. Regular `git_config` defaults + * to `NULL`. + * -+ * `opts`:: ++ * - `opts` + * Specify options to adjust the behavior of parsing config files. See `struct + * config_options` in `config.h` for details. As an example: regular `git_config` + * sets `opts.respect_includes` to `1` by default. @@ -110,8 +440,7 @@ + * Value Parsing Helpers + * --------------------- + * -+ * To aid in parsing string values, the config API provides callbacks with -+ * a number of helper functions ++ * The following helper functions aid in parsing string values + */ + int git_parse_ssize_t(const char *, ssize_t *); @@ -128,12 +457,14 @@ + * otherwise, returns the parsed result. + */ int git_config_int(const char *, const char *); ++ int64_t git_config_int64(const char *, const char *); + +/** + * Identical to `git_config_int`, but for unsigned longs. + */ unsigned long git_config_ulong(const char *, const char *); ++ ssize_t git_config_ssize_t(const char *, const char *); + +/** @@ -161,22 +492,24 @@ + * user's home directory when found at the beginning of the path. + */ int git_config_pathname(const char **, const char *, const char *); ++ int git_config_expiry_date(timestamp_t *, const char *, const char *); int git_config_color(char *, const char *, const char *); int git_config_set_in_file_gently(const char *, const char *, const char *); + +/** -+ * write config values to a specific config file -+ * takes a key/value pair as parameter. ++ * write config values to a specific config file, takes a key/value pair as ++ * parameter. + */ void git_config_set_in_file(const char *, const char *, const char *); ++ int git_config_set_gently(const char *, const char *); + +/** -+ * write config values to `.git/config` -+ * takes a key/value pair as parameter. ++ * write config values to `.git/config`, takes a key/value pair as parameter. + */ void git_config_set(const char *, const char *); ++ int git_config_parse_key(const char *, char **, int *); int git_config_key_is_valid(const char *key); int git_config_set_multivar_gently(const char *, const char *, const char *, int); @@ -214,8 +547,10 @@ + * the section will be removed from the config file. + */ int git_config_rename_section(const char *, const char *); ++ int git_config_rename_section_in_file(const char *, const char *, const char *); int git_config_copy_section(const char *, const char *); + int git_config_copy_section_in_file(const char *, const char *, const char *); @@ const char *current_config_origin_type(void); const char *current_config_name(void); @@ -325,8 +660,10 @@ + * is owned by the cache. + */ int git_configset_get_value(struct config_set *cs, const char *key, const char **dest); ++ int git_configset_get_string_const(struct config_set *cs, const char *key, const char **dest); int git_configset_get_string(struct config_set *cs, const char *key, char **dest); + int git_configset_get_int(struct config_set *cs, const char *key, int *dest); @@ int repo_config_get_pathname(struct repository *repo, const char *key, const char **dest); @@ -418,8 +755,10 @@ + * the user's home directory when found at the beginning of the path. + */ int git_config_get_pathname(const char *key, const char **dest); ++ int git_config_get_index_threads(int *dest); int git_config_get_untracked_cache(void); + int git_config_get_split_index(void); @@ enum config_scope scope; }; -- gitgitgadget
