git/config.h
Jeff King 9a53219f69 config: drop git_config_get_string_const()
As evidenced by the leak fixes in the previous commit, the "const" in
git_config_get_string_const() clearly misleads people into thinking that
it does not allocate a copy of the string. We can fix this by renaming
it, but it's easier still to just drop it. Of the four remaining
callers:

  - The one in git_config_parse_expiry() still needs to allocate, since
    that's what its callers expect. We can just use the non-const
    version and cast our pointer. Slightly ugly, but the damage is
    contained in one spot.

  - The two in apply are writing to global "const char *" variables, and
    need to continue allocating. We often mark these as const because we
    assign default string literals to them. But in this case we don't do
    that, so we can just declare them as real "char *" pointers and use
    the non-const version.

  - The call in checkout doesn't actually need a copy; it can just use
    the non-allocating "tmp" version of the function.

The function is also mentioned in the MyFirstContribution document. We
can swap that call out for the non-allocating "tmp" variant, which fits
well in the example given.

We'll drop the "configset" and "repo" variants, as well (which are
unused).

Note that this frees up the "const" name, so we could rename the "tmp"
variant back to that. But let's give some time for topics in flight to
adapt to the new code before doing so (if we do it too soon, the
function semantics will change but the compiler won't alert us).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-08-17 15:35:47 -07:00

622 lines
22 KiB
C

#ifndef CONFIG_H
#define CONFIG_H
#include "hashmap.h"
#include "string-list.h"
/**
* The config API gives callers a way to access Git configuration files
* (and files which have the same 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.
*/
struct object_id;
/* git_config_parse_key() returns these negated: */
#define CONFIG_INVALID_KEY 1
#define CONFIG_NO_SECTION_OR_NAME 2
/* git_config_set_gently(), git_config_set_multivar_gently() return the above or these: */
#define CONFIG_NO_LOCK -1
#define CONFIG_INVALID_FILE 3
#define CONFIG_NO_WRITE 4
#define CONFIG_NOTHING_SET 5
#define CONFIG_INVALID_PATTERN 6
#define CONFIG_GENERIC_ERROR 7
#define CONFIG_REGEX_NONE ((void *)1)
enum config_scope {
CONFIG_SCOPE_UNKNOWN = 0,
CONFIG_SCOPE_SYSTEM,
CONFIG_SCOPE_GLOBAL,
CONFIG_SCOPE_LOCAL,
CONFIG_SCOPE_WORKTREE,
CONFIG_SCOPE_COMMAND,
CONFIG_SCOPE_SUBMODULE,
};
const char *config_scope_name(enum config_scope scope);
struct git_config_source {
unsigned int use_stdin:1;
const char *file;
const char *blob;
enum config_scope scope;
};
enum config_origin_type {
CONFIG_ORIGIN_BLOB,
CONFIG_ORIGIN_FILE,
CONFIG_ORIGIN_STDIN,
CONFIG_ORIGIN_SUBMODULE_BLOB,
CONFIG_ORIGIN_CMDLINE
};
enum config_event_t {
CONFIG_EVENT_SECTION,
CONFIG_EVENT_ENTRY,
CONFIG_EVENT_WHITESPACE,
CONFIG_EVENT_COMMENT,
CONFIG_EVENT_EOF,
CONFIG_EVENT_ERROR
};
/*
* The parser event function (if not NULL) is called with the event type and
* the begin/end offsets of the parsed elements.
*
* Note: for CONFIG_EVENT_ENTRY (i.e. config variables), the trailing newline
* character is considered part of the element.
*/
typedef int (*config_parser_event_fn_t)(enum config_event_t type,
size_t begin_offset, size_t end_offset,
void *event_fn_data);
struct config_options {
unsigned int respect_includes : 1;
unsigned int ignore_repo : 1;
unsigned int ignore_worktree : 1;
unsigned int ignore_cmdline : 1;
unsigned int system_gently : 1;
const char *commondir;
const char *git_dir;
config_parser_event_fn_t event_fn;
void *event_fn_data;
enum config_error_action {
CONFIG_ERROR_UNSET = 0, /* use source-specific default */
CONFIG_ERROR_DIE, /* die() on error */
CONFIG_ERROR_ERROR, /* error() on error, return -1 */
CONFIG_ERROR_SILENT, /* return -1 */
} error_action;
};
/**
* 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.
*/
typedef int (*config_fn_t)(const char *, const char *, void *);
int git_default_config(const char *, const char *, void *);
/**
* Read a specific file in git-config format.
* 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_mem(config_fn_t fn,
const enum config_origin_type,
const char *name,
const char *buf, size_t len,
void *data, const struct config_options *opts);
int git_config_from_blob_oid(config_fn_t fn, const char *name,
const struct object_id *oid, void *data);
void git_config_push_parameter(const char *text);
int git_config_from_parameters(config_fn_t fn, void *data);
void read_early_config(config_fn_t cb, void *data);
void read_very_early_config(config_fn_t cb, void *data);
/**
* 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).
*/
void git_config(config_fn_t fn, void *);
/**
* 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.
*/
int config_with_options(config_fn_t fn, void *,
struct git_config_source *config_source,
const struct config_options *opts);
/**
* Value Parsing Helpers
* ---------------------
*
* The following helper functions aid in parsing string values
*/
int git_parse_ssize_t(const char *, ssize_t *);
int git_parse_ulong(const char *, unsigned long *);
/**
* Same as `git_config_bool`, except that it returns -1 on error rather
* than dying.
*/
int git_parse_maybe_bool(const char *);
/**
* Parse the string to an integer, including unit factors. Dies on error;
* 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 *);
/**
* Same as `git_config_bool`, except that integers are returned as-is, and
* an `is_bool` flag is unset.
*/
int git_config_bool_or_int(const char *, const char *, int *);
/**
* 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.
*/
int git_config_bool(const char *, const char *);
/**
* Allocates and copies the value string into the `dest` parameter; if no
* string is given, prints an error message and returns -1.
*/
int git_config_string(const char **, const char *, const char *);
/**
* Similar to `git_config_string`, but expands `~` or `~user` into the
* 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.
*/
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.
*/
void git_config_set(const char *, const char *);
int git_config_parse_key(const char *, char **, size_t *);
int git_config_key_is_valid(const char *key);
int git_config_set_multivar_gently(const char *, const char *, const char *, int);
void git_config_set_multivar(const char *, const char *, const char *, int);
int git_config_set_multivar_in_file_gently(const char *, const char *, const char *, const char *, int);
/**
* 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.
*/
void git_config_set_multivar_in_file(const char *, const char *, const char *, const char *, int);
/**
* rename or remove sections in the config file
* parameters `old_name` and `new_name`
* If NULL is passed through `new_name` parameter,
* 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 *git_etc_gitconfig(void);
int git_env_bool(const char *, int);
unsigned long git_env_ulong(const char *, unsigned long);
int git_config_system(void);
int config_error_nonbool(const char *);
#if defined(__GNUC__)
#define config_error_nonbool(s) (config_error_nonbool(s), const_error())
#endif
int git_config_parse_parameter(const char *, config_fn_t fn, void *data);
enum config_scope current_config_scope(void);
const char *current_config_origin_type(void);
const char *current_config_name(void);
int current_config_line(void);
/**
* 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.
*
*/
struct config_include_data {
int depth;
config_fn_t fn;
void *data;
const struct config_options *opts;
};
#define CONFIG_INCLUDE_INIT { 0 }
int git_config_include(const char *name, const char *value, void *data);
/*
* Match and parse a config key of the form:
*
* section.(subsection.)?key
*
* (i.e., what gets handed to a config_fn_t). The caller provides the section;
* we return -1 if it does not match, 0 otherwise. The subsection and key
* out-parameters are filled by the function (and *subsection is NULL if it is
* missing).
*
* If the subsection pointer-to-pointer passed in is NULL, returns 0 only if
* there is no subsection at all.
*/
int parse_config_key(const char *var,
const char *section,
const char **subsection, size_t *subsection_len,
const char **key);
/**
* 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
*/
struct config_set_element {
struct hashmap_entry ent;
char *key;
struct string_list value_list;
};
struct configset_list_item {
struct config_set_element *e;
int value_index;
};
/*
* the contents of the list are ordered according to their
* position in the config files and order of parsing the files.
* (i.e. key-value pair at the last position of .git/config will
* be at the last item of the list)
*/
struct configset_list {
struct configset_list_item *items;
unsigned int nr, alloc;
};
struct config_set {
struct hashmap config_hash;
int hash_initialized;
struct configset_list list;
};
/**
* Initializes the config_set `cs`.
*/
void git_configset_init(struct config_set *cs);
/**
* 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_add_file(struct config_set *cs, const char *filename);
/**
* 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.
*/
const struct string_list *git_configset_get_value_multi(struct config_set *cs, const char *key);
/**
* Clears `config_set` structure, removes all saved variable-value pairs.
*/
void git_configset_clear(struct config_set *cs);
/*
* These functions return 1 if not found, and 0 if found, leaving the found
* value in the 'dest' pointer.
*/
/*
* 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.
*/
int git_configset_get_value(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_string_tmp(struct config_set *cs, const char *key, const char **dest);
int git_configset_get_int(struct config_set *cs, const char *key, int *dest);
int git_configset_get_ulong(struct config_set *cs, const char *key, unsigned long *dest);
int git_configset_get_bool(struct config_set *cs, const char *key, int *dest);
int git_configset_get_bool_or_int(struct config_set *cs, const char *key, int *is_bool, int *dest);
int git_configset_get_maybe_bool(struct config_set *cs, const char *key, int *dest);
int git_configset_get_pathname(struct config_set *cs, const char *key, const char **dest);
/* Functions for reading a repository's config */
struct repository;
void repo_config(struct repository *repo, config_fn_t fn, void *data);
int repo_config_get_value(struct repository *repo,
const char *key, const char **value);
const struct string_list *repo_config_get_value_multi(struct repository *repo,
const char *key);
int repo_config_get_string(struct repository *repo,
const char *key, char **dest);
int repo_config_get_string_tmp(struct repository *repo,
const char *key, const char **dest);
int repo_config_get_int(struct repository *repo,
const char *key, int *dest);
int repo_config_get_ulong(struct repository *repo,
const char *key, unsigned long *dest);
int repo_config_get_bool(struct repository *repo,
const char *key, int *dest);
int repo_config_get_bool_or_int(struct repository *repo,
const char *key, int *is_bool, int *dest);
int repo_config_get_maybe_bool(struct repository *repo,
const char *key, int *dest);
int repo_config_get_pathname(struct repository *repo,
const char *key, const char **dest);
/**
* 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.
*/
/**
* 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.
*/
int git_config_get_value(const char *key, const char **value);
/**
* 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.
*/
const struct string_list *git_config_get_value_multi(const char *key);
/**
* Resets and invalidates the config cache.
*/
void git_config_clear(void);
/**
* 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`, but does not allocate any new
* memory; on success `dest` will point to memory owned by the config
* machinery, which could be invalidated if it is discarded and reloaded.
*/
int git_config_get_string_tmp(const char *key, const char **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_int(const char *key, int *dest);
/**
* Similar to `git_config_get_int` but for unsigned longs.
*/
int git_config_get_ulong(const char *key, unsigned long *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(const char *key, 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_bool_or_int(const char *key, int *is_bool, int *dest);
/**
* Similar to `git_config_get_bool`, except that it returns -1 on error
* rather than dying.
*/
int git_config_get_maybe_bool(const char *key, int *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.
*/
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);
int git_config_get_max_percent_split_change(void);
int git_config_get_fsmonitor(void);
/* This dies if the configured or default date is in the future */
int git_config_get_expiry(const char *key, const char **output);
/* parse either "this many days" integer, or "5.days.ago" approxidate */
int git_config_get_expiry_in_days(const char *key, timestamp_t *, timestamp_t now);
struct key_value_info {
const char *filename;
int linenr;
enum config_origin_type origin_type;
enum config_scope scope;
};
/**
* 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`.
*/
NORETURN void git_die_config(const char *key, const char *err, ...) __attribute__((format(printf, 2, 3)));
/**
* 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.
*/
NORETURN void git_die_config_linenr(const char *key, const char *filename, int linenr);
#define LOOKUP_CONFIG(mapping, var) \
lookup_config(mapping, ARRAY_SIZE(mapping), var)
int lookup_config(const char **mapping, int nr_mapping, const char *var);
#endif /* CONFIG_H */