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