git-commit-vandalism/config.h

650 lines
22 KiB
C
Raw Normal View History

#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;
/* The repository if blob is not NULL; leave blank for the_repository */
struct repository *repo;
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;
/*
* For internal use. Include all includeif.hasremoteurl paths without
* checking if the repo has that remote URL, and when doing so, verify
* that files included in this way do not configure any remote URLs
* themselves.
*/
unsigned int unconditional_remote_url : 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`.
*
* Unlike git_config(), this function does not respect includes.
*/
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,
struct repository *repo,
const struct object_id *oid, void *data);
void git_config_push_parameter(const char *text);
void git_config_push_env(const char *spec);
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).
*
* Unlike git_config_from_file(), this function respects includes.
*/
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 a config value that should apply to the current worktree. If
* extensions.worktreeConfig is enabled, then the write will happen in the
* current worktree's config. Otherwise, write to the common config file.
*/
int repo_config_set_worktree_gently(struct repository *, 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 *);
/*
* The following macros specify flag bits that alter the behavior
* of the git_config_set_multivar*() methods.
*/
/*
* When CONFIG_FLAGS_MULTI_REPLACE is specified, all matching key/values
* are removed before a single new pair is written. If the flag is not
* present, then set operations replace only the first match.
*/
#define CONFIG_FLAGS_MULTI_REPLACE (1 << 0)
/*
* When CONFIG_FLAGS_FIXED_VALUE is specified, match key/value pairs
* by string comparison (not regex match) to the provided value_pattern
* parameter.
*/
#define CONFIG_FLAGS_FIXED_VALUE (1 << 1)
int git_config_set_multivar_gently(const char *, const char *, const char *, unsigned);
void git_config_set_multivar(const char *, const char *, const char *, unsigned);
int repo_config_set_multivar_gently(struct repository *, const char *, const char *, const char *, unsigned);
int git_config_set_multivar_in_file_gently(const char *, const char *, const char *, const char *, unsigned);
/**
* 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 flags value with bits corresponding to the CONFIG_FLAG_* macros.
*
* It returns 0 on success.
*/
void git_config_set_multivar_in_file(const char *config_filename,
const char *key,
const char *value,
const char *value_pattern,
unsigned flags);
/**
* 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 *);
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
char *git_system_config(void);
void git_global_config(char **user, char **xdg);
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);
/*
* 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 caller decides
* whether 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);
config: learn `git_protected_config()` `uploadpack.packObjectsHook` is the only 'protected configuration only' variable today, but we've noted that `safe.directory` and the upcoming `safe.bareRepository` should also be 'protected configuration only'. So, for consistency, we'd like to have a single implementation for protected configuration. The primary constraints are: 1. Reading from protected configuration should be fast. Nearly all "git" commands inside a bare repository will read both `safe.directory` and `safe.bareRepository`, so we cannot afford to be slow. 2. Protected configuration must be readable when the gitdir is not known. `safe.directory` and `safe.bareRepository` both affect repository discovery and the gitdir is not known at that point [1]. The chosen implementation in this commit is to read protected configuration and cache the values in a global configset. This is similar to the caching behavior we get with the_repository->config. Introduce git_protected_config(), which reads protected configuration and caches them in the global configset protected_config. Then, refactor `uploadpack.packObjectsHook` to use git_protected_config(). The protected configuration functions are named similarly to their non-protected counterparts, e.g. git_protected_config_check_init() vs git_config_check_init(). In light of constraint 1, this implementation can still be improved. git_protected_config() iterates through every variable in protected_config, which is wasteful, but it makes the conversion simple because it matches existing patterns. We will likely implement constant time lookup functions for protected configuration in a future series (such functions already exist for non-protected configuration, i.e. repo_config_get_*()). An alternative that avoids introducing another configset is to continue to read all config using git_config(), but only accept values that have the correct config scope [2]. This technically fulfills constraint 2, because git_config() simply ignores the local and worktree config when the gitdir is not known. However, this would read incomplete config into the_repository->config, which would need to be reset when the gitdir is known and git_config() needs to read the local and worktree config. Resetting the_repository->config might be reasonable while we only have these 'protected configuration only' variables, but it's not clear whether this extends well to future variables. [1] In this case, we do have a candidate gitdir though, so with a little refactoring, it might be possible to provide a gitdir. [2] This is how `uploadpack.packObjectsHook` was implemented prior to this commit. Signed-off-by: Glen Choo <chooglen@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-07-14 23:27:59 +02:00
/**
* Parses command line options and environment variables, and adds the
* variable-value pairs to the `config_set`. Returns 0 on success, or -1
* if there is an error in parsing. The caller decides whether to free
* the incomplete configset or continue using it when the function
* returns -1.
*/
int git_configset_add_parameters(struct config_set *cs);
/**
* 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_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);
config: fix leaks from git_config_get_string_const() There are two functions to get a single config string: - git_config_get_string() - git_config_get_string_const() One might naively think that the first one allocates a new string and the second one just points us to the internal configset storage. But in fact they both allocate a new copy; the second one exists only to avoid having to cast when using it with a const global which we never intend to free. The documentation for the function explains that clearly, but it seems I'm not alone in being surprised by this. Of 17 calls to the function, 13 of them leak the resulting value. We could obviously fix these by adding the appropriate free(). But it would be simpler still if we actually had a non-allocating way to get the string. There's git_config_get_value() but that doesn't quite do what we want. If the config key is present but is a boolean with no value (e.g., "[foo]bar" in the file), then we'll get NULL (whereas the string versions will print an error and die). So let's introduce a new variant, git_config_get_string_tmp(), that behaves as these callers expect. We need a new name because we have new semantics but the same function signature (so even if we converted the four remaining callers, topics in flight might be surprised). The "tmp" is because this value should only be held onto for a short time. In practice it's rare for us to clear and refresh the configset, invalidating the pointer, but hopefully the "tmp" makes callers think about the lifetime. In each of the converted cases here the value only needs to last within the local function or its immediate caller. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-08-14 18:17:36 +02:00
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);
config: learn `git_protected_config()` `uploadpack.packObjectsHook` is the only 'protected configuration only' variable today, but we've noted that `safe.directory` and the upcoming `safe.bareRepository` should also be 'protected configuration only'. So, for consistency, we'd like to have a single implementation for protected configuration. The primary constraints are: 1. Reading from protected configuration should be fast. Nearly all "git" commands inside a bare repository will read both `safe.directory` and `safe.bareRepository`, so we cannot afford to be slow. 2. Protected configuration must be readable when the gitdir is not known. `safe.directory` and `safe.bareRepository` both affect repository discovery and the gitdir is not known at that point [1]. The chosen implementation in this commit is to read protected configuration and cache the values in a global configset. This is similar to the caching behavior we get with the_repository->config. Introduce git_protected_config(), which reads protected configuration and caches them in the global configset protected_config. Then, refactor `uploadpack.packObjectsHook` to use git_protected_config(). The protected configuration functions are named similarly to their non-protected counterparts, e.g. git_protected_config_check_init() vs git_config_check_init(). In light of constraint 1, this implementation can still be improved. git_protected_config() iterates through every variable in protected_config, which is wasteful, but it makes the conversion simple because it matches existing patterns. We will likely implement constant time lookup functions for protected configuration in a future series (such functions already exist for non-protected configuration, i.e. repo_config_get_*()). An alternative that avoids introducing another configset is to continue to read all config using git_config(), but only accept values that have the correct config scope [2]. This technically fulfills constraint 2, because git_config() simply ignores the local and worktree config when the gitdir is not known. However, this would read incomplete config into the_repository->config, which would need to be reset when the gitdir is known and git_config() needs to read the local and worktree config. Resetting the_repository->config might be reasonable while we only have these 'protected configuration only' variables, but it's not clear whether this extends well to future variables. [1] In this case, we do have a candidate gitdir though, so with a little refactoring, it might be possible to provide a gitdir. [2] This is how `uploadpack.packObjectsHook` was implemented prior to this commit. Signed-off-by: Glen Choo <chooglen@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-07-14 23:27:59 +02:00
/*
* Functions for reading protected config. By definition, protected
* config ignores repository config, so these do not take a `struct
* repository` parameter.
*/
void git_protected_config(config_fn_t fn, void *data);
/**
* 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);
config: fix leaks from git_config_get_string_const() There are two functions to get a single config string: - git_config_get_string() - git_config_get_string_const() One might naively think that the first one allocates a new string and the second one just points us to the internal configset storage. But in fact they both allocate a new copy; the second one exists only to avoid having to cast when using it with a const global which we never intend to free. The documentation for the function explains that clearly, but it seems I'm not alone in being surprised by this. Of 17 calls to the function, 13 of them leak the resulting value. We could obviously fix these by adding the appropriate free(). But it would be simpler still if we actually had a non-allocating way to get the string. There's git_config_get_value() but that doesn't quite do what we want. If the config key is present but is a boolean with no value (e.g., "[foo]bar" in the file), then we'll get NULL (whereas the string versions will print an error and die). So let's introduce a new variant, git_config_get_string_tmp(), that behaves as these callers expect. We need a new name because we have new semantics but the same function signature (so even if we converted the four remaining callers, topics in flight might be surprised). The "tmp" is because this value should only be held onto for a short time. In practice it's rare for us to clear and refresh the configset, invalidating the pointer, but hopefully the "tmp" makes callers think about the lifetime. In each of the converted cases here the value only needs to last within the local function or its immediate caller. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-08-14 18:17:36 +02:00
/**
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 23:33:11 +02:00
* Similar to `git_config_get_string`, but does not allocate any new
config: fix leaks from git_config_get_string_const() There are two functions to get a single config string: - git_config_get_string() - git_config_get_string_const() One might naively think that the first one allocates a new string and the second one just points us to the internal configset storage. But in fact they both allocate a new copy; the second one exists only to avoid having to cast when using it with a const global which we never intend to free. The documentation for the function explains that clearly, but it seems I'm not alone in being surprised by this. Of 17 calls to the function, 13 of them leak the resulting value. We could obviously fix these by adding the appropriate free(). But it would be simpler still if we actually had a non-allocating way to get the string. There's git_config_get_value() but that doesn't quite do what we want. If the config key is present but is a boolean with no value (e.g., "[foo]bar" in the file), then we'll get NULL (whereas the string versions will print an error and die). So let's introduce a new variant, git_config_get_string_tmp(), that behaves as these callers expect. We need a new name because we have new semantics but the same function signature (so even if we converted the four remaining callers, topics in flight might be surprised). The "tmp" is because this value should only be held onto for a short time. In practice it's rare for us to clear and refresh the configset, invalidating the pointer, but hopefully the "tmp" makes callers think about the lifetime. In each of the converted cases here the value only needs to last within the local function or its immediate caller. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-08-14 18:17:36 +02:00
* 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_split_index(void);
int git_config_get_max_percent_split_change(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 */