1 /*
2  * Copyright (c) 2018 Stefan Sperling <stsp@openbsd.org>
3  *
4  * Permission to use, copy, modify, and distribute this software for any
5  * purpose with or without fee is hereby granted, provided that the above
6  * copyright notice and this permission notice appear in all copies.
7  *
8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15  */
16 
17 /*
18  * Compute the differences between two blobs and write unified diff text
19  * to the provided output FILE. Two const char * diff header labels may
20  * be provided which will be used to identify each blob in the diff output.
21  * If a label is NULL, use the blob's SHA1 checksum instead.
22  * The number of context lines to show in the diff must be specified as well.
23  */
24 const struct got_error *got_diff_blob(struct got_blob_object *,
25     struct got_blob_object *, const char *, const char *, int, FILE *);
26 
27 /*
28  * Compute the differences between a blob and a file and write unified diff
29  * text to the provided output file. The file's size must be provided, as
30  * well as a const char * diff header label which identifies the file.
31  * The number of context lines to show in the diff must be specified as well.
32  */
33 const struct got_error *got_diff_blob_file(struct got_blob_object *, FILE *,
34     size_t, const char *, int, FILE *);
35 
36 /*
37  * A callback function invoked to handle the differences between two blobs
38  * when diffing trees with got_diff_tree(). This callback receives two blobs,
39  * their respective IDs, and two corresponding paths within the diffed trees.
40  * The first blob contains content from the old side of the diff, and
41  * the second blob contains content on the new side of the diff.
42  * The set of arguments relating to either blob may be NULL to indicate
43  * that no content is present on its respective side of the diff.
44  */
45 typedef const struct got_error *(*got_diff_blob_cb)(void *,
46     struct got_blob_object *, struct got_blob_object *,
47     struct got_object_id *, struct got_object_id *,
48     const char *, const char *, struct got_repository *);
49 
50 /*
51  * A pre-defined implementation of got_diff_blob_cb() which appends unidiff
52  * output to a file. The caller must allocate and fill in the argument
53  * structure.
54  */
55 struct got_diff_blob_output_unidiff_arg {
56 	FILE *outfile;		/* Unidiff text will be written here. */
57 	int diff_context;	/* Sets the number of context lines. */
58 };
59 const struct got_error *got_diff_blob_output_unidiff(void *,
60     struct got_blob_object *, struct got_blob_object *,
61     struct got_object_id *, struct got_object_id *,
62     const char *, const char *, struct got_repository *);
63 
64 /*
65  * Compute the differences between two trees and invoke the provided
66  * got_diff_blob_cb() callback when content differs.
67  */
68 const struct got_error *got_diff_tree(struct got_tree_object *,
69     struct got_tree_object *, const char *, const char *,
70     struct got_repository *, got_diff_blob_cb cb, void *cb_arg);
71 
72 /*
73  * Diff two objects, assuming both objects are blobs. Two const char * diff
74  * header labels may be provided which will be used to identify each blob in
75  * the diff output. If a label is NULL, use the blob's SHA1 checksum instead.
76  * The number of context lines to show in the diff must be specified as well.
77  * Write unified diff text to the provided output FILE.
78  */
79 const struct got_error *got_diff_objects_as_blobs(struct got_object_id *,
80     struct got_object_id *, const char *, const char *, int,
81     struct got_repository *, FILE *);
82 
83 /*
84  * Diff two objects, assuming both objects are trees. Two const char * diff
85  * header labels may be provided which will be used to identify each blob in
86  * the trees. If a label is NULL, use the blob's SHA1 checksum instead.
87  * The number of context lines to show in diffs must be specified.
88  * Write unified diff text to the provided output FILE.
89  */
90 const struct got_error *got_diff_objects_as_trees(struct got_object_id *,
91     struct got_object_id *, char *, char *, int, struct got_repository *, FILE *);
92 
93 /*
94  * Diff two objects, assuming both objects are commits.
95  * The number of context lines to show in diffs must be specified.
96  * Write unified diff text to the provided output FILE.
97  */
98 const struct got_error *got_diff_objects_as_commits(struct got_object_id *,
99     struct got_object_id *, int, struct got_repository *, FILE *);
100 
101 #define GOT_DIFF_MAX_CONTEXT	64