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