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 struct got_tree_object;
21 struct got_tag_object;
22 
23 struct got_tree_entry {
24 	SIMPLEQ_ENTRY(got_tree_entry) entry;
25 	mode_t mode;
26 	char *name;
27 	struct got_object_id *id;
28 };
29 
30 SIMPLEQ_HEAD(got_tree_entries_queue, got_tree_entry);
31 
32 struct got_tree_entries {
33 	int nentries;
34 	struct got_tree_entries_queue head;
35 };
36 
37 struct got_object_qid {
38 	SIMPLEQ_ENTRY(got_object_qid) entry;
39 	struct got_object_id *id;
40 };
41 
42 SIMPLEQ_HEAD(got_object_id_queue, got_object_qid);
43 
44 const struct got_error *got_object_qid_alloc(struct got_object_qid **,
45     struct got_object_id *);
46 void got_object_qid_free(struct got_object_qid *);
47 
48 struct got_commit_object {
49 	struct got_object_id *tree_id;
50 	unsigned int nparents;
51 	struct got_object_id_queue parent_ids;
52 	char *author;
53 	time_t author_time;	/* UTC */
54 	time_t author_gmtoff;
55 	char *committer;
56 	time_t committer_time;	/* UTC */
57 	time_t committer_gmtoff;
58 	char *logmsg;
59 
60 	int refcnt; /* for internal use only */
61 };
62 
63 /* A generic object. Used as a handle which holds an ID and an object type. */
64 struct got_object;
65 #define GOT_OBJ_TYPE_COMMIT		1
66 #define GOT_OBJ_TYPE_TREE		2
67 #define GOT_OBJ_TYPE_BLOB		3
68 #define GOT_OBJ_TYPE_TAG		4
69 /* 5 is reserved */
70 #define GOT_OBJ_TYPE_OFFSET_DELTA	6
71 #define GOT_OBJ_TYPE_REF_DELTA		7
72 
73 struct got_repository;
74 
75 /*
76  * Obtain a string representation of an object ID. The output depends on
77  * the hash function used by the repository format (currently SHA1).
78  */
79 const struct got_error *got_object_id_str(char **, struct got_object_id *);
80 
81 /*
82  * Compare two object IDs. Return value behaves like memcmp(3).
83  */
84 int got_object_id_cmp(const struct got_object_id *,
85     const struct got_object_id *);
86 
87 /*
88  * Created a newly allocated copy of an object ID.
89  * The caller should dispose of it with free(3).
90  */
91 struct got_object_id *got_object_id_dup(struct got_object_id *);
92 
93 /*
94  * Get a newly allocated copy of an object's ID.
95  * The caller must treat the ID as read-only and must not call free(3) on it.
96  * Use got_object_id_dup() to get a writable copy.
97  */
98 struct got_object_id *got_object_get_id(struct got_object *);
99 
100 /*
101  * Get a newly allocated copy of an object's ID string.
102  * The caller should dispose of it with free(3).
103  */
104 const struct got_error *got_object_get_id_str(char **, struct got_object *);
105 
106 /*
107  * Get a newly allocated ID of the object which resides at the specified
108  * path in the tree of the specified commit.
109  * The caller should dispose of it with free(3).
110  */
111 const struct got_error *
112 got_object_id_by_path(struct got_object_id **, struct got_repository *,
113     struct got_object_id *, const char *);
114 
115 /*
116  * Obtain the type of an object.
117  * Returns one of the GOT_OBJ_TYPE_x values (see above).
118  */
119 int got_object_get_type(struct got_object *);
120 
121 /*
122  * Attempt to open the object in a repository with the provided ID.
123  * Caller must dispose of it with got_object_close().
124  */
125 const struct got_error *got_object_open(struct got_object **,
126     struct got_repository *, struct got_object_id *);
127 
128 /*
129  * Attempt to map the provided ID string to an object ID and then
130  * attempt to open the object in a repository with this ID.
131  * The form of an ID string depends on the hash function used by the
132  * repository format (currently SHA1).
133  * Caller must dispose of the object with got_object_close().
134  */
135 const struct got_error *got_object_open_by_id_str(struct got_object **,
136     struct got_repository *, const char *);
137 
138 /* Dispose of an object. */
139 void got_object_close(struct got_object *);
140 
141 /*
142  * Attempt to open a commit object in a repository.
143  * The provided object must be of type GOT_OBJ_TYPE_COMMIT.
144  * The caller must dispose of the commit with got_object_commit_close().
145  */
146 const struct got_error *got_object_commit_open(struct got_commit_object **,
147     struct got_repository *, struct got_object *);
148 
149 /* Dispose of a commit object. */
150 void got_object_commit_close(struct got_commit_object *);
151 
152 /*
153  * Attempt to open a tree object in a repository.
154  * The provided object must be of type GOT_OBJ_TYPE_TREE.
155  * The caller must dispose of the tree with got_object_tree_close().
156  */
157 const struct got_error *got_object_tree_open(struct got_tree_object **,
158     struct got_repository *, struct got_object *);
159 
160 /* Dispose of a tree object. */
161 void got_object_tree_close(struct got_tree_object *);
162 
163 /* Get the entries of a tree object. */
164 const struct got_tree_entries *got_object_tree_get_entries(
165     struct got_tree_object *);
166 
167 /*
168  * Compare two trees and indicate whether the entry at the specified path
169  * differs between them. The path must not be the root path "/"; the function
170  * got_object_id_cmp() should be used instead to compare the tree roots.
171  */
172 const struct got_error *got_object_tree_path_changed(int *,
173     struct got_tree_object *, struct got_tree_object *, const char *,
174     struct got_repository *);
175 
176 /*
177  * Attempt to open a blob object in a repository.
178  * The provided object must be of type GOT_OBJ_TYPE_BLOB.
179  * The size_t argument specifies the block size of an associated read buffer.
180  * The caller must dispose of the blob with got_object_blob_close().
181  */
182 const struct got_error *got_object_blob_open(struct got_blob_object **,
183     struct got_repository *, struct got_object *, size_t);
184 
185 /* Dispose of a blob object. */
186 void got_object_blob_close(struct got_blob_object *);
187 
188 /*
189  * Write the string representation of the object ID of a blob to a buffer.
190  * The size_t argument speficies the size of the buffer. In the current
191  * implementation, it must be at least SHA1_DIGEST_STRING_LENGTH bytes.
192  * XXX This is a bad API, use got_object_id_str() instead.
193  */
194 char *got_object_blob_id_str(struct got_blob_object*, char *, size_t);
195 
196 /*
197  * Get the length of header data at the beginning of the blob's read buffer.
198  * Note that header data is only present upon the first invocation of
199  * got_object_blob_read_block() after the blob is opened.
200  */
201 size_t got_object_blob_get_hdrlen(struct got_blob_object *);
202 
203 /*
204  * Get a pointer to the blob's read buffer.
205  * The read buffer is filled by got_object_blob_read_block().
206  */
207 const uint8_t *got_object_blob_get_read_buf(struct got_blob_object *);
208 
209 /*
210  * Read the next chunk of data from a blob, up to the blob's read buffer
211  * block size. The size_t output argument indicates how many bytes have
212  * been read into the blob's read buffer. Zero bytes will be reported if
213  * all data in the blob has been read.
214  */
215 const struct got_error *got_object_blob_read_block(size_t *,
216     struct got_blob_object *);
217 
218 /*
219  * Read the entire content of a blob and write it to the specified file.
220  * Flush and rewind the file as well. Indicate the amount of bytes
221  * written in the first size_t output argument, and the number of lines
222  * in the file in the second size_t output argument (NULL can be passed
223  * for either output argument).
224  */
225 const struct got_error *got_object_blob_dump_to_file(size_t *, size_t *,
226     FILE *, struct got_blob_object *);
227 
228 /*
229  * Attempt to open a tag object in a repository.
230  * The provided object must be of type GOT_OBJ_TYPE_TAG.
231  * The caller must dispose of the tree with got_object_tag_close().
232  */
233 const struct got_error *got_object_tag_open(struct got_tag_object **,
234     struct got_repository *, struct got_object *);
235 
236 /* Dispose of a tag object. */
237 void got_object_tag_close(struct got_tag_object *);
238 
239 const struct got_error *
240 got_object_open_as_commit(struct got_commit_object **,
241     struct got_repository *, struct got_object_id *);
242 const struct got_error *
243 got_object_open_as_tree(struct got_tree_object **,
244     struct got_repository *, struct got_object_id *);
245 const struct got_error *
246 got_object_open_as_blob(struct got_blob_object **,
247     struct got_repository *, struct got_object_id *, size_t);
248 const struct got_error *got_object_open_as_tag(struct got_tag_object **,
249     struct got_repository *, struct got_object_id *);
250 
251 const struct got_error *got_object_commit_add_parent(struct got_commit_object *,
252     const char *);