diffcore.h - jrn/git - Git at Google

 /*
  * Copyright (C) 2005 Junio C Hamano
  */
 #ifndef DIFFCORE_H
 #define DIFFCORE_H

 #include "cache.h"

 struct diff_options;
 struct repository;
 struct strintmap;
 struct strmap;
 struct userdiff_driver;

 /* This header file is internal between diff.c and its diff transformers
  * (e.g. diffcore-rename, diffcore-pickaxe).  Never include this header
  * in anything else.
  */

 /* We internally use unsigned short as the score value,
  * and rely on an int capable to hold 32-bits.  -B can take
  * -Bmerge_score/break_score format and the two scores are
  * passed around in one int (high 16-bit for merge and low 16-bit
  * for break).
  */
 #define MAX_SCORE 60000.0
 #define DEFAULT_RENAME_SCORE 30000 /* rename/copy similarity minimum (50%) */
 #define DEFAULT_BREAK_SCORE  30000 /* minimum for break to happen (50%) */
 #define DEFAULT_MERGE_SCORE  36000 /* maximum for break-merge to happen (60%) */

 #define MINIMUM_BREAK_SIZE     400 /* do not break a file smaller than this */

 /**
  * the internal representation for a single file (blob).  It records the blob
  * object name (if known -- for a work tree file it typically is a NUL SHA-1),
  * filemode and pathname.  This is what the `diff_addremove()`, `diff_change()`
  * and `diff_unmerge()` synthesize and feed `diff_queue()` function with.
  */
 struct diff_filespec {
 	struct object_id oid;
 	char *path;
 	void *data;
 	void *cnt_data;
 	unsigned long size;
 	int count;               /* Reference count */
 	int rename_used;         /* Count of rename users */
 	unsigned short mode;	 /* file mode */
 	unsigned oid_valid : 1;  /* if true, use oid and trust mode;
 				  * if false, use the name and read from
 				  * the filesystem.
 				  */
 #define DIFF_FILE_VALID(spec) (((spec)->mode) != 0)
 	unsigned should_free : 1; /* data should be free()'ed */
 	unsigned should_munmap : 1; /* data should be munmap()'ed */
 	unsigned dirty_submodule : 2;  /* For submodules: its work tree is dirty */
 #define DIRTY_SUBMODULE_UNTRACKED 1
 #define DIRTY_SUBMODULE_MODIFIED  2
 	unsigned is_stdin : 1;
 	unsigned has_more_entries : 1; /* only appear in combined diff */
 	/* data should be considered "binary"; -1 means "don't know yet" */
 	signed int is_binary : 2;
 	struct userdiff_driver *driver;
 };

 struct diff_filespec *alloc_filespec(const char *);
 void free_filespec(struct diff_filespec *);
 void fill_filespec(struct diff_filespec *, const struct object_id *,
 		   int, unsigned short);

 /*
  * Prefetch the entries in diff_queued_diff. The parameter is a pointer to a
  * struct repository.
  */
 void diff_queued_diff_prefetch(void *repository);

 struct diff_populate_filespec_options {
 	unsigned check_size_only : 1;
 	unsigned check_binary : 1;

 	/*
 	 * If an object is missing, diff_populate_filespec() will invoke this
 	 * callback before attempting to read that object again.
 	 */
 	void (*missing_object_cb)(void *);
 	void *missing_object_data;
 };
 int diff_populate_filespec(struct repository *, struct diff_filespec *,
 			   const struct diff_populate_filespec_options *);
 void diff_free_filespec_data(struct diff_filespec *);
 void diff_free_filespec_blob(struct diff_filespec *);
 int diff_filespec_is_binary(struct repository *, struct diff_filespec *);

 /**
  * This records a pair of `struct diff_filespec`; the filespec for a file in
  * the "old" set (i.e. preimage) is called `one`, and the filespec for a file
  * in the "new" set (i.e. postimage) is called `two`.  A change that represents
  * file creation has NULL in `one`, and file deletion has NULL in `two`.
  *
  * A `filepair` starts pointing at `one` and `two` that are from the same
  * filename, but `diffcore_std()` can break pairs and match component filespecs
  * with other filespecs from a different filepair to form new filepair. This is
  * called 'rename detection'.
  */
 struct diff_filepair {
 	struct diff_filespec *one;
 	struct diff_filespec *two;
 	unsigned short int score;
 	char status; /* M C R A D U etc. (see Documentation/diff-format.txt or DIFF_STATUS_* in diff.h) */
 	unsigned broken_pair : 1;
 	unsigned renamed_pair : 1;
 	unsigned is_unmerged : 1;
 	unsigned done_skip_stat_unmatch : 1;
 	unsigned skip_stat_unmatch_result : 1;
 };

 #define DIFF_PAIR_UNMERGED(p) ((p)->is_unmerged)

 #define DIFF_PAIR_RENAME(p) ((p)->renamed_pair)

 #define DIFF_PAIR_BROKEN(p) \
 	( (!DIFF_FILE_VALID((p)->one) != !DIFF_FILE_VALID((p)->two)) && \
 	  ((p)->broken_pair != 0) )

 #define DIFF_PAIR_TYPE_CHANGED(p) \
 	((S_IFMT & (p)->one->mode) != (S_IFMT & (p)->two->mode))

 #define DIFF_PAIR_MODE_CHANGED(p) ((p)->one->mode != (p)->two->mode)

 void diff_free_filepair(struct diff_filepair *);
 void pool_diff_free_filepair(struct mem_pool *pool,
 			     struct diff_filepair *p);

 int diff_unmodified_pair(struct diff_filepair *);

 /**
  * This is a collection of filepairs.  Notable members are:
  *
  * - `queue`:
  * An array of pointers to `struct diff_filepair`. This dynamically grows as
  * you add filepairs;
  *
  * - `alloc`:
  * The allocated size of the `queue` array;
  *
  * - `nr`:
  * The number of elements in the `queue` array.
  */
 struct diff_queue_struct {
 	struct diff_filepair **queue;
 	int alloc;
 	int nr;
 };

 #define DIFF_QUEUE_CLEAR(q) \
 	do { \
 		(q)->queue = NULL; \
 		(q)->nr = (q)->alloc = 0; \
 	} while (0)

 extern struct diff_queue_struct diff_queued_diff;
 struct diff_filepair *diff_queue(struct diff_queue_struct *,
 				 struct diff_filespec *,
 				 struct diff_filespec *);
 void diff_q(struct diff_queue_struct *, struct diff_filepair *);
 void diff_free_queue(struct diff_queue_struct *q);

 /* dir_rename_relevance: the reason we want rename information for a dir */
 enum dir_rename_relevance {
 	NOT_RELEVANT = 0,
 	RELEVANT_FOR_ANCESTOR = 1,
 	RELEVANT_FOR_SELF = 2
 };
 /* file_rename_relevance: the reason(s) we want rename information for a file */
 enum file_rename_relevance {
 	RELEVANT_NO_MORE = 0,  /* i.e. NOT relevant */
 	RELEVANT_CONTENT = 1,
 	RELEVANT_LOCATION = 2
 };

 void partial_clear_dir_rename_count(struct strmap *dir_rename_count);

 void diffcore_break(struct repository *, int);
 void diffcore_rename(struct diff_options *);
 void diffcore_rename_extended(struct diff_options *options,
 			      struct mem_pool *pool,
 			      struct strintmap *relevant_sources,
 			      struct strintmap *dirs_removed,
 			      struct strmap *dir_rename_count,
 			      struct strmap *cached_pairs);
 void diffcore_merge_broken(void);
 void diffcore_pickaxe(struct diff_options *);
 void diffcore_order(const char *orderfile);
 void diffcore_rotate(struct diff_options *);

 /* low-level interface to diffcore_order */
 struct obj_order {
 	void *obj;	/* setup by caller */

 	/* setup/used by order_objects() */
 	int orig_order;
 	int order;
 };

 typedef const char *(*obj_path_fn_t)(void *obj);

 void order_objects(const char *orderfile, obj_path_fn_t obj_path,
 		   struct obj_order *objs, int nr);

 #define DIFF_DEBUG 0
 #if DIFF_DEBUG
 void diff_debug_filespec(struct diff_filespec *, int, const char *);
 void diff_debug_filepair(const struct diff_filepair *, int);
 void diff_debug_queue(const char *, struct diff_queue_struct *);
 #else
 #define diff_debug_filespec(a,b,c) do { /* nothing */ } while (0)
 #define diff_debug_filepair(a,b) do { /* nothing */ } while (0)
 #define diff_debug_queue(a,b) do { /* nothing */ } while (0)
 #endif

 int diffcore_count_changes(struct repository *r,
 			   struct diff_filespec *src,
 			   struct diff_filespec *dst,
 			   void **src_count_p,
 			   void **dst_count_p,
 			   unsigned long *src_copied,
 			   unsigned long *literal_added);

 /*
  * If filespec contains an OID and if that object is missing from the given
  * repository, add that OID to to_fetch.
  */
 void diff_add_if_missing(struct repository *r,
 			 struct oid_array *to_fetch,
 			 const struct diff_filespec *filespec);

 #endif
	/*
	* Copyright (C) 2005 Junio C Hamano
	*/
	#ifndef DIFFCORE_H
	#define DIFFCORE_H

	#include "cache.h"

	struct diff_options;
	struct repository;
	struct strintmap;
	struct strmap;
	struct userdiff_driver;

	/* This header file is internal between diff.c and its diff transformers
	* (e.g. diffcore-rename, diffcore-pickaxe). Never include this header
	* in anything else.
	*/

	/* We internally use unsigned short as the score value,
	* and rely on an int capable to hold 32-bits. -B can take
	* -Bmerge_score/break_score format and the two scores are
	* passed around in one int (high 16-bit for merge and low 16-bit
	* for break).
	*/
	#define MAX_SCORE 60000.0
	#define DEFAULT_RENAME_SCORE 30000 /* rename/copy similarity minimum (50%) */
	#define DEFAULT_BREAK_SCORE 30000 /* minimum for break to happen (50%) */
	#define DEFAULT_MERGE_SCORE 36000 /* maximum for break-merge to happen (60%) */

	#define MINIMUM_BREAK_SIZE 400 /* do not break a file smaller than this */

	/**
	* the internal representation for a single file (blob). It records the blob
	* object name (if known -- for a work tree file it typically is a NUL SHA-1),
	* filemode and pathname. This is what the `diff_addremove()`, `diff_change()`
	* and `diff_unmerge()` synthesize and feed `diff_queue()` function with.
	*/
	struct diff_filespec {
	struct object_id oid;
	char *path;
	void *data;
	void *cnt_data;
	unsigned long size;
	int count; /* Reference count */
	int rename_used; /* Count of rename users */
	unsigned short mode; /* file mode */
	unsigned oid_valid : 1; /* if true, use oid and trust mode;
	* if false, use the name and read from
	* the filesystem.
	*/
	#define DIFF_FILE_VALID(spec) (((spec)->mode) != 0)
	unsigned should_free : 1; /* data should be free()'ed */
	unsigned should_munmap : 1; /* data should be munmap()'ed */
	unsigned dirty_submodule : 2; /* For submodules: its work tree is dirty */
	#define DIRTY_SUBMODULE_UNTRACKED 1
	#define DIRTY_SUBMODULE_MODIFIED 2
	unsigned is_stdin : 1;
	unsigned has_more_entries : 1; /* only appear in combined diff */
	/* data should be considered "binary"; -1 means "don't know yet" */
	signed int is_binary : 2;
	struct userdiff_driver *driver;
	};

	struct diff_filespec alloc_filespec(const char );
	void free_filespec(struct diff_filespec *);
	void fill_filespec(struct diff_filespec , const struct object_id ,
	int, unsigned short);

	/*
	* Prefetch the entries in diff_queued_diff. The parameter is a pointer to a
	* struct repository.
	*/
	void diff_queued_diff_prefetch(void *repository);

	struct diff_populate_filespec_options {
	unsigned check_size_only : 1;
	unsigned check_binary : 1;

	/*
	* If an object is missing, diff_populate_filespec() will invoke this
	* callback before attempting to read that object again.
	*/
	void (missing_object_cb)(void );
	void *missing_object_data;
	};
	int diff_populate_filespec(struct repository , struct diff_filespec ,
	const struct diff_populate_filespec_options *);
	void diff_free_filespec_data(struct diff_filespec *);
	void diff_free_filespec_blob(struct diff_filespec *);
	int diff_filespec_is_binary(struct repository , struct diff_filespec );

	/**
	* This records a pair of `struct diff_filespec`; the filespec for a file in
	* the "old" set (i.e. preimage) is called `one`, and the filespec for a file
	* in the "new" set (i.e. postimage) is called `two`. A change that represents
	* file creation has NULL in `one`, and file deletion has NULL in `two`.
	*
	* A `filepair` starts pointing at `one` and `two` that are from the same
	* filename, but `diffcore_std()` can break pairs and match component filespecs
	* with other filespecs from a different filepair to form new filepair. This is
	* called 'rename detection'.
	*/
	struct diff_filepair {
	struct diff_filespec *one;
	struct diff_filespec *two;
	unsigned short int score;
	char status; /* M C R A D U etc. (see Documentation/diff-format.txt or DIFF_STATUS_* in diff.h) */
	unsigned broken_pair : 1;
	unsigned renamed_pair : 1;
	unsigned is_unmerged : 1;
	unsigned done_skip_stat_unmatch : 1;
	unsigned skip_stat_unmatch_result : 1;
	};

	#define DIFF_PAIR_UNMERGED(p) ((p)->is_unmerged)

	#define DIFF_PAIR_RENAME(p) ((p)->renamed_pair)

	#define DIFF_PAIR_BROKEN(p) \
	( (!DIFF_FILE_VALID((p)->one) != !DIFF_FILE_VALID((p)->two)) && \
	((p)->broken_pair != 0) )

	#define DIFF_PAIR_TYPE_CHANGED(p) \
	((S_IFMT & (p)->one->mode) != (S_IFMT & (p)->two->mode))

	#define DIFF_PAIR_MODE_CHANGED(p) ((p)->one->mode != (p)->two->mode)

	void diff_free_filepair(struct diff_filepair *);
	void pool_diff_free_filepair(struct mem_pool *pool,
	struct diff_filepair *p);

	int diff_unmodified_pair(struct diff_filepair *);

	/**
	* This is a collection of filepairs. Notable members are:
	*
	* - `queue`:
	* An array of pointers to `struct diff_filepair`. This dynamically grows as
	* you add filepairs;
	*
	* - `alloc`:
	* The allocated size of the `queue` array;
	*
	* - `nr`:
	* The number of elements in the `queue` array.
	*/
	struct diff_queue_struct {
	struct diff_filepair **queue;
	int alloc;
	int nr;
	};

	#define DIFF_QUEUE_CLEAR(q) \
	do { \
	(q)->queue = NULL; \
	(q)->nr = (q)->alloc = 0; \
	} while (0)

	extern struct diff_queue_struct diff_queued_diff;
	struct diff_filepair diff_queue(struct diff_queue_struct ,
	struct diff_filespec *,
	struct diff_filespec *);
	void diff_q(struct diff_queue_struct , struct diff_filepair );
	void diff_free_queue(struct diff_queue_struct *q);

	/* dir_rename_relevance: the reason we want rename information for a dir */
	enum dir_rename_relevance {
	NOT_RELEVANT = 0,
	RELEVANT_FOR_ANCESTOR = 1,
	RELEVANT_FOR_SELF = 2
	};
	/* file_rename_relevance: the reason(s) we want rename information for a file */
	enum file_rename_relevance {
	RELEVANT_NO_MORE = 0, /* i.e. NOT relevant */
	RELEVANT_CONTENT = 1,
	RELEVANT_LOCATION = 2
	};

	void partial_clear_dir_rename_count(struct strmap *dir_rename_count);

	void diffcore_break(struct repository *, int);
	void diffcore_rename(struct diff_options *);
	void diffcore_rename_extended(struct diff_options *options,
	struct mem_pool *pool,
	struct strintmap *relevant_sources,
	struct strintmap *dirs_removed,
	struct strmap *dir_rename_count,
	struct strmap *cached_pairs);
	void diffcore_merge_broken(void);
	void diffcore_pickaxe(struct diff_options *);
	void diffcore_order(const char *orderfile);
	void diffcore_rotate(struct diff_options *);

	/* low-level interface to diffcore_order */
	struct obj_order {
	void obj; / setup by caller */

	/* setup/used by order_objects() */
	int orig_order;
	int order;
	};

	typedef const char (obj_path_fn_t)(void *obj);

	void order_objects(const char *orderfile, obj_path_fn_t obj_path,
	struct obj_order *objs, int nr);

	#define DIFF_DEBUG 0
	#if DIFF_DEBUG
	void diff_debug_filespec(struct diff_filespec , int, const char );
	void diff_debug_filepair(const struct diff_filepair *, int);
	void diff_debug_queue(const char , struct diff_queue_struct );
	#else
	#define diff_debug_filespec(a,b,c) do { /* nothing */ } while (0)
	#define diff_debug_filepair(a,b) do { /* nothing */ } while (0)
	#define diff_debug_queue(a,b) do { /* nothing */ } while (0)
	#endif

	int diffcore_count_changes(struct repository *r,
	struct diff_filespec *src,
	struct diff_filespec *dst,
	void **src_count_p,
	void **dst_count_p,
	unsigned long *src_copied,
	unsigned long *literal_added);

	/*
	* If filespec contains an OID and if that object is missing from the given
	* repository, add that OID to to_fetch.
	*/
	void diff_add_if_missing(struct repository *r,
	struct oid_array *to_fetch,
	const struct diff_filespec *filespec);

	#endif