1 files changed, 238 insertions, 0 deletions
diff --git a/diffcore.h b/diffcore.h
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+/*
+ * Copyright (C) 2005 Junio C Hamano
+ */
+#ifndef DIFFCORE_H
+#define DIFFCORE_H
+
+#include "hash-ll.h"
+
+struct diff_options;
+struct mem_pool;
+struct oid_array;
+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