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 struct got_commit_object {
44 	struct got_object_id *tree_id;
45 	unsigned int nparents;
46 	struct got_object_id_queue parent_ids;
47 	char *author;
48 	struct tm tm_author;	/* UTC */
49 	char *committer;
50 	struct tm tm_committer;	/* UTC */
51 	char *logmsg;
52 
53 	int refcnt; /* for internal use only */
54 };
55 
56 /* A generic object. Used as a handle which holds an ID and an object type. */
57 struct got_object;
58 #define GOT_OBJ_TYPE_COMMIT		1
59 #define GOT_OBJ_TYPE_TREE		2
60 #define GOT_OBJ_TYPE_BLOB		3
61 #define GOT_OBJ_TYPE_TAG		4
62 /* 5 is reserved */
63 #define GOT_OBJ_TYPE_OFFSET_DELTA	6
64 #define GOT_OBJ_TYPE_REF_DELTA		7
65 
66 struct got_repository;
67 
68 /*
69  * Obtain a string representation of an object ID. The output depends on
70  * the hash function used by the repository format (currently SHA1).
71  */
72 const struct got_error *got_object_id_str(char **, struct got_object_id *);
73 
74 /*
75  * Compare two object IDs. Return value behaves like memcmp(3).
76  */
77 int got_object_id_cmp(struct got_object_id *, struct got_object_id *);
78 
79 /*
80  * Created a newly allocated copy of an object ID.
81  * The caller should dispose of it with free(3).
82  */
83 struct got_object_id *got_object_id_dup(struct got_object_id *);
84 
85 /*
86  * Get a newly allocated copy of an object's ID.
87  * The caller should dispose of it with free(3).
88  */
89 struct got_object_id *got_object_get_id(struct got_object *);
90 
91 /*
92  * Get a newly allocated copy of an object's ID string.
93  * The caller should dispose of it with free(3).
94  */
95 const struct got_error *got_object_get_id_str(char **, struct got_object *);
96 
97 /*
98  * Obtain the type of an object.
99  * Returns one of the GOT_OBJ_TYPE_x values (see above).
100  */
101 int got_object_get_type(struct got_object *);
102 
103 /*
104  * Attempt to open the object in a repository with the provided ID.
105  * Caller must dispose of it with got_object_close().
106  */
107 const struct got_error *got_object_open(struct got_object **,
108     struct got_repository *, struct got_object_id *);
109 
110 /*
111  * Attempt to map the provided ID string to an object ID and then
112  * attempt to open the object in a repository with this ID.
113  * The form of an ID string depends on the hash function used by the
114  * repository format (currently SHA1).
115  * Caller must dispose of the object with got_object_close().
116  */
117 const struct got_error *got_object_open_by_id_str(struct got_object **,
118     struct got_repository *, const char *);
119 
120 /* Dispose of an object. */
121 void got_object_close(struct got_object *);
122 
123 /*
124  * Attempt to open a commit object in a repository.
125  * The provided object must be of type GOT_OBJ_TYPE_COMMIT.
126  * The caller must dispose of the commit with got_object_commit_close().
127  */
128 const struct got_error *got_object_commit_open(struct got_commit_object **,
129     struct got_repository *, struct got_object *);
130 
131 /* Dispose of a commit object. */
132 void got_object_commit_close(struct got_commit_object *);
133 
134 /*
135  * Attempt to open a tree object in a repository.
136  * The provided object must be of type GOT_OBJ_TYPE_TREE.
137  * The caller must dispose of the tree with got_object_tree_close().
138  */
139 const struct got_error *got_object_tree_open(struct got_tree_object **,
140     struct got_repository *, struct got_object *);
141 
142 /* Dispose of a tree object. */
143 void got_object_tree_close(struct got_tree_object *);
144 
145 /* Get the entries of a tree object. */
146 const struct got_tree_entries *got_object_tree_get_entries(
147     struct got_tree_object *);
148 
149 /*
150  * Attempt to open a blob object in a repository.
151  * The provided object must be of type GOT_OBJ_TYPE_BLOB.
152  * The size_t argument specifies the block size of an associated read buffer.
153  * The caller must dispose of the blob with got_object_blob_close().
154  */
155 const struct got_error *got_object_blob_open(struct got_blob_object **,
156     struct got_repository *, struct got_object *, size_t);
157 
158 /* Dispose of a blob object. */
159 void got_object_blob_close(struct got_blob_object *);
160 
161 /*
162  * Write the string representation of the object ID of a blob to a buffer.
163  * The size_t argument speficies the size of the buffer. In the current
164  * implementation, it must be at least SHA1_DIGEST_STRING_LENGTH bytes.
165  * XXX This is a bad API, use got_object_id_str() instead.
166  */
167 char *got_object_blob_id_str(struct got_blob_object*, char *, size_t);
168 
169 /*
170  * Get the length of header data at the beginning of the blob's read buffer.
171  * Note that header data is only present upon the first invocation of
172  * got_object_blob_read_block() after the blob is opened.
173  */
174 size_t got_object_blob_get_hdrlen(struct got_blob_object *);
175 
176 /*
177  * Get a pointer to the blob's read buffer.
178  * The read buffer is filled by got_object_blob_read_block().
179  */
180 const uint8_t *got_object_blob_get_read_buf(struct got_blob_object *);
181 
182 /*
183  * Read the next chunk of data from a blob, up to the blob's read buffer
184  * block size. The size_t output argument indicates how many bytes have
185  * been read into the blob's read buffer. Zero bytes will be reported if
186  * all data in the blob has been read.
187  */
188 const struct got_error *got_object_blob_read_block(size_t *,
189     struct got_blob_object *);
190 
191 /*
192  * Read the entire content of a blob and write it to the specified file.
193  * Flush and rewind the file as well, and indicate the amount of bytes
194  * written in the size_t output argument.
195  */
196 const struct got_error *got_object_blob_dump_to_file(size_t *, FILE *,
197     struct got_blob_object *);
198 
199 const struct got_error *
200 got_object_open_as_commit(struct got_commit_object **,
201     struct got_repository *, struct got_object_id *);
202 const struct got_error *
203 got_object_open_as_tree(struct got_tree_object **,
204     struct got_repository *, struct got_object_id *);
205 const struct got_error *
206 got_object_open_as_blob(struct got_blob_object **,
207     struct got_repository *, struct got_object_id *, size_t);
208 
209 const struct got_error *
210 got_object_open_by_path(struct got_object **, struct got_repository *,
211     struct got_object_id *, const char *);
212 
213 const struct got_error *got_object_commit_add_parent(struct got_commit_object *,
214     const char *);