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 struct got_object_id;
18 
19 struct got_blob_object;
20 
21 struct got_tree_entry {
22 	SIMPLEQ_ENTRY(got_tree_entry) entry;
23 	mode_t mode;
24 	char *name;
25 	struct got_object_id *id;
26 };
27 
28 struct got_tree_object {
29 	int nentries;
30 	SIMPLEQ_HEAD(, got_tree_entry) entries;
31 };
32 
33 struct got_parent_id {
34 	SIMPLEQ_ENTRY(got_parent_id) entry;
35 	struct got_object_id *id;
36 };
37 
38 struct got_commit_object {
39 	struct got_object_id *tree_id;
40 	unsigned int nparents;
41 	SIMPLEQ_HEAD(, got_parent_id) parent_ids;
42 	char *author;
43 	char *committer;
44 	char *logmsg;
45 };
46 
47 /* A generic object. Used as a handle which holds an ID and an object type. */
48 struct got_object;
49 #define GOT_OBJ_TYPE_COMMIT		1
50 #define GOT_OBJ_TYPE_TREE		2
51 #define GOT_OBJ_TYPE_BLOB		3
52 #define GOT_OBJ_TYPE_TAG		4
53 /* 5 is reserved */
54 #define GOT_OBJ_TYPE_OFFSET_DELTA	6
55 #define GOT_OBJ_TYPE_REF_DELTA		7
56 
57 struct got_repository;
58 
59 /*
60  * Obtain a string representation of an object ID. The output depends on
61  * the hash function used by the repository format (currently SHA1).
62  */
63 const struct got_error *got_object_id_str(char **, struct got_object_id *);
64 
65 /*
66  * Compare two object IDs. Return value behaves like memcmp(3).
67  */
68 int got_object_id_cmp(struct got_object_id *, struct got_object_id *);
69 
70 /*
71  * Created a newly allocated copy of an object ID.
72  * The caller should dispose of it with free(3).
73  */
74 struct got_object_id *got_object_id_dup(struct got_object_id *);
75 
76 /*
77  * Get a newly allocated copy of an object's ID.
78  * The caller should dispose of it with free(3).
79  */
80 struct got_object_id *got_object_get_id(struct got_object *);
81 
82 /*
83  * Obtain the type of an object.
84  * Returns one of the GOT_OBJ_TYPE_x values (see above).
85  */
86 int got_object_get_type(struct got_object *);
87 
88 /*
89  * Attempt to open the object in a repository with the provided ID.
90  * Caller must dispose of it with got_object_close().
91  */
92 const struct got_error *got_object_open(struct got_object **,
93     struct got_repository *, struct got_object_id *);
94 
95 /*
96  * Attempt to map the provided ID string to an object ID and then
97  * attempt to open the object in a repository with this ID.
98  * The form of an ID string depends on the hash function used by the
99  * repository format (currently SHA1).
100  * Caller must dispose of the object with got_object_close().
101  */
102 const struct got_error *got_object_open_by_id_str(struct got_object **,
103     struct got_repository *, const char *);
104 
105 /* Dispose of an object. */
106 void got_object_close(struct got_object *);
107 
108 /*
109  * Attempt to open a commit object in a repository.
110  * The provided object must be of type GOT_OBJ_TYPE_COMMIT.
111  * The caller must dispose of the commit with got_object_commit_close().
112  */
113 const struct got_error *got_object_commit_open(struct got_commit_object **,
114     struct got_repository *, struct got_object *);
115 
116 /* Dispose of a commit object. */
117 void got_object_commit_close(struct got_commit_object *);
118 
119 /*
120  * Attempt to open a tree object in a repository.
121  * The provided object must be of type GOT_OBJ_TYPE_TREE.
122  * The caller must dispose of the tree with got_object_tree_close().
123  */
124 const struct got_error *got_object_tree_open(struct got_tree_object **,
125     struct got_repository *, struct got_object *);
126 
127 /* Dispose of a tree object. */
128 void got_object_tree_close(struct got_tree_object *);
129 
130 /*
131  * Attempt to open a blob object in a repository.
132  * The provided object must be of type GOT_OBJ_TYPE_BLOB.
133  * The size_t argument specifies the block size of an associated read buffer.
134  * The caller must dispose of the blob with got_object_blob_close().
135  */
136 const struct got_error *got_object_blob_open(struct got_blob_object **,
137     struct got_repository *, struct got_object *, size_t);
138 
139 /* Dispose of a blob object. */
140 void got_object_blob_close(struct got_blob_object *);
141 
142 /*
143  * Write the string representation of the object ID of a blob to a buffer.
144  * The size_t argument speficies the size of the buffer. In the current
145  * implementation, it must be at least SHA1_DIGEST_STRING_LENGTH bytes.
146  * XXX This is a bad API, use got_object_id_str() instead.
147  */
148 char *got_object_blob_id_str(struct got_blob_object*, char *, size_t);
149 
150 /*
151  * Get the length of header data at the beginning of the blob's read buffer.
152  * Note that header data is only present upon the first invocation of
153  * got_object_blob_read_block() after the blob is opened.
154  */
155 size_t got_object_blob_get_hdrlen(struct got_blob_object *);
156 
157 /*
158  * Get a pointer to the blob's read buffer.
159  * The read buffer is filled by got_object_blob_read_block().
160  */
161 const uint8_t *got_object_blob_get_read_buf(struct got_blob_object *);
162 
163 /*
164  * Read the next chunk of data from a blob, up to the blob's read buffer
165  * block size. The size_t output argument indicates how many bytes have
166  * been read into the blob's read buffer. Zero bytes will be reported if
167  * all data in the blob has been read.
168  */
169 const struct got_error *got_object_blob_read_block(size_t *,
170     struct got_blob_object *);
171 const struct got_error *got_object_commit_add_parent(struct got_commit_object *,
172     const char *);