git/userdiff.h
John Cai a4cf900ee7 diff: teach diff to read algorithm from diff driver
It can be useful to specify diff algorithms per file type. For example,
one may want to use the minimal diff algorithm for .json files, another
for .c files, etc.

The diff machinery already checks attributes for a diff driver. Teach
the diff driver parser a new type "algorithm" to look for in the
config, which will be used if a driver has been specified through the
attributes.

Enforce precedence of the diff algorithm by favoring the command line
option, then looking at the driver attributes & config combination, then
finally the diff.algorithm config.

To enforce precedence order, use a new `ignore_driver_algorithm` member
during options parsing to indicate the diff algorithm was set via command
line args.

Signed-off-by: John Cai <johncai86@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-02-21 09:29:10 -08:00

52 lines
1.3 KiB
C

#ifndef USERDIFF_H
#define USERDIFF_H
#include "notes-cache.h"
struct index_state;
struct repository;
struct userdiff_funcname {
const char *pattern;
int cflags;
};
struct userdiff_driver {
const char *name;
const char *external;
const char *algorithm;
int binary;
struct userdiff_funcname funcname;
const char *word_regex;
const char *textconv;
struct notes_cache *textconv_cache;
int textconv_want_cache;
};
enum userdiff_driver_type {
USERDIFF_DRIVER_TYPE_BUILTIN = 1<<0,
USERDIFF_DRIVER_TYPE_CUSTOM = 1<<1,
};
typedef int (*each_userdiff_driver_fn)(struct userdiff_driver *,
enum userdiff_driver_type, void *);
int userdiff_config(const char *k, const char *v);
struct userdiff_driver *userdiff_find_by_name(const char *name);
struct userdiff_driver *userdiff_find_by_path(struct index_state *istate,
const char *path);
/*
* Initialize any textconv-related fields in the driver and return it, or NULL
* if it does not have textconv enabled at all.
*/
struct userdiff_driver *userdiff_get_textconv(struct repository *r,
struct userdiff_driver *driver);
/*
* Iterate over all userdiff drivers. The userdiff_driver_type
* argument to each_userdiff_driver_fn indicates their type. Return
* non-zero to exit early from the loop.
*/
int for_each_userdiff_driver(each_userdiff_driver_fn, void *);
#endif /* USERDIFF */