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 #include <sys/queue.h>
18 #include <sys/stat.h>
19 
20 #include <limits.h>
21 #include <stdlib.h>
22 #include <stdio.h>
23 #include <sha1.h>
24 #include <string.h>
25 #include <zlib.h>
26 
27 #include "got_error.h"
28 #include "got_reference.h"
29 #include "got_repository.h"
30 #include "got_worktree.h"
31 #include "got_object.h"
32 
33 #include "got_lib_path.h"
34 #include "got_lib_delta.h"
35 #include "got_lib_zbuf.h"
36 #include "got_lib_object.h"
37 #include "got_lib_pack.h"
38 #include "got_lib_repository.h"
39 #include "got_lib_worktree.h"
40 
41 #ifndef nitems
42 #define nitems(_a) (sizeof(_a) / sizeof((_a)[0]))
43 #endif
44 
45 #define GOT_GIT_DIR	".git"
46 
47 /* Mandatory files and directories inside the git directory. */
48 #define GOT_OBJECTS_DIR		"objects"
49 #define GOT_REFS_DIR		"refs"
50 #define GOT_HEAD_FILE		"HEAD"
51 
52 /* Other files and directories inside the git directory. */
53 #define GOT_FETCH_HEAD_FILE	"FETCH_HEAD"
54 #define GOT_ORIG_HEAD_FILE	"ORIG_HEAD"
55 #define GOT_OBJECTS_PACK_DIR	"objects/pack"
56 
57 char *
58 got_repo_get_path(struct got_repository *repo)
59 {
60 	return strdup(repo->path);
61 }
62 
63 char *
64 got_repo_get_path_git_dir(struct got_repository *repo)
65 {
66 	return strdup(repo->path_git_dir);
67 }
68 
69 static char *
70 get_path_git_child(struct got_repository *repo, const char *basename)
71 {
72 	char *path_child;
73 	
74 	if (asprintf(&path_child, "%s/%s", repo->path_git_dir,
75 	    basename) == -1)
76 		return NULL;
77 
78 	return path_child;
79 }
80 
81 char *
82 got_repo_get_path_objects(struct got_repository *repo)
83 {
84 	return get_path_git_child(repo, GOT_OBJECTS_DIR);
85 }
86 
87 char *
88 got_repo_get_path_objects_pack(struct got_repository *repo)
89 {
90 	return get_path_git_child(repo, GOT_OBJECTS_PACK_DIR);
91 }
92 
93 char *
94 got_repo_get_path_refs(struct got_repository *repo)
95 {
96 	return get_path_git_child(repo, GOT_REFS_DIR);
97 }
98 
99 static char *
100 get_path_head(struct got_repository *repo)
101 {
102 	return get_path_git_child(repo, GOT_HEAD_FILE);
103 }
104 
105 static int
106 is_git_repo(struct got_repository *repo)
107 {
108 	char *path_git = got_repo_get_path_git_dir(repo);
109 	char *path_objects = got_repo_get_path_objects(repo);
110 	char *path_refs = got_repo_get_path_refs(repo);
111 	char *path_head = get_path_head(repo);
112 	int ret = 0;
113 	struct stat sb;
114 	struct got_reference *head_ref;
115 
116 	if (lstat(path_git, &sb) == -1)
117 		goto done;
118 	if (!S_ISDIR(sb.st_mode))
119 		goto done;
120 
121 	if (lstat(path_objects, &sb) == -1)
122 		goto done;
123 	if (!S_ISDIR(sb.st_mode))
124 		goto done;
125 
126 	if (lstat(path_refs, &sb) == -1)
127 		goto done;
128 	if (!S_ISDIR(sb.st_mode))
129 		goto done;
130 
131 	if (lstat(path_head, &sb) == -1)
132 		goto done;
133 	if (!S_ISREG(sb.st_mode))
134 		goto done;
135 
136 	/* Check if the HEAD reference can be opened. */
137 	if (got_ref_open(&head_ref, repo, GOT_REF_HEAD) != NULL)
138 		goto done;
139 	got_ref_close(head_ref);
140 
141 	ret = 1;
142 done:
143 	free(path_git);
144 	free(path_objects);
145 	free(path_refs);
146 	free(path_head);
147 	return ret;
148 
149 }
150 
151 const struct got_error*
152 got_repo_cache_object(struct got_repository *repo, struct got_object_id *id,
153     struct got_object *obj)
154 {
155 	struct got_objcache_entry *ce;
156 
157 	if (repo->ncached >= GOT_OBJECT_CACHE_SIZE) {
158 		ce = SIMPLEQ_FIRST(&repo->objcache);
159 		SIMPLEQ_REMOVE_HEAD(&repo->objcache, entry);
160 		got_object_close(ce->obj);
161 		free(ce);
162 		repo->ncached--;
163 	}
164 
165 	ce = calloc(1, sizeof(*ce));
166 	if (ce == NULL)
167 		return got_error_from_errno();
168 	memcpy(&ce->id, id, sizeof(ce->id));
169 	ce->obj = obj;
170 	obj->refcnt++;
171 	SIMPLEQ_INSERT_HEAD(&repo->objcache, ce, entry);
172 	repo->ncached++;
173 	return NULL;
174 }
175 
176 struct got_object *
177 got_repo_get_cached_object(struct got_repository *repo,
178     struct got_object_id *id)
179 {
180 	struct got_objcache_entry *ce;
181 
182 	SIMPLEQ_FOREACH(ce, &repo->objcache, entry) {
183 		if (got_object_id_cmp(&ce->id, id) != 0)
184 			continue;
185 		repo->cache_hit++;
186 		return ce->obj;
187 	}
188 	repo->cache_miss++;
189 	return NULL;
190 }
191 
192 const struct got_error *
193 got_repo_open(struct got_repository **ret, const char *path)
194 {
195 	struct got_repository *repo = NULL;
196 	const struct got_error *err = NULL;
197 	char *abspath;
198 
199 	if (got_path_is_absolute(path))
200 		abspath = strdup(path);
201 	else
202 		abspath = got_path_get_absolute(path);
203 	if (abspath == NULL)
204 		return got_error(GOT_ERR_BAD_PATH);
205 
206 	repo = calloc(1, sizeof(*repo));
207 	if (repo == NULL) {
208 		err = got_error_from_errno();
209 		goto done;
210 	}
211 
212 	repo->path = got_path_normalize(abspath);
213 	if (repo->path == NULL) {
214 		err = got_error(GOT_ERR_BAD_PATH);
215 		goto done;
216 	}
217 
218 	repo->path_git_dir = strdup(repo->path);
219 	if (repo->path_git_dir == NULL) {
220 		err = got_error_from_errno();
221 		goto done;
222 	}
223 	if (!is_git_repo(repo)) {
224 		free(repo->path_git_dir);
225 		if (asprintf(&repo->path_git_dir, "%s/%s", repo->path,
226 		    GOT_GIT_DIR) == -1) {
227 			err = got_error_from_errno();
228 			goto done;
229 		}
230 		if (!is_git_repo(repo)) {
231 			struct got_worktree *worktree;
232 			if (got_worktree_open(&worktree, repo->path) == NULL) {
233 				free(repo->path_git_dir);
234 				repo->path_git_dir =
235 				    strdup(worktree->repo_path);
236 				if (repo->path_git_dir == NULL) {
237 					err = got_error_from_errno();
238 					goto done;
239 				}
240 				if (!is_git_repo(repo)) {
241 					free(repo->path_git_dir);
242 					if (asprintf(&repo->path_git_dir,
243 					    "%s/%s", worktree->repo_path,
244 					    GOT_GIT_DIR) == -1) {
245 						err = got_error_from_errno();
246 						goto done;
247 					}
248 				}
249 				got_worktree_close(worktree);
250 			}
251 		}
252 		if (!is_git_repo(repo)) {
253 			err = got_error(GOT_ERR_NOT_GIT_REPO);
254 			goto done;
255 		}
256 	}
257 		
258 	*ret = repo;
259 done:
260 	if (err)
261 		got_repo_close(repo);
262 	free(abspath);
263 	return err;
264 }
265 
266 void
267 got_repo_close(struct got_repository *repo)
268 {
269 	int i;
270 
271 	for (i = 0; i < nitems(repo->packidx_cache); i++) {
272 		if (repo->packidx_cache[i] == NULL)
273 			break;
274 		got_packidx_close(repo->packidx_cache[i]);
275 	}
276 
277 	for (i = 0; i < nitems(repo->packs); i++) {
278 		if (repo->packs[i].path_packfile == NULL)
279 			break;
280 		got_pack_close(&repo->packs[i]);
281 	}
282 
283 	while (!SIMPLEQ_EMPTY(&repo->objcache)) {
284 		struct got_objcache_entry *ce;
285 		ce = SIMPLEQ_FIRST(&repo->objcache);
286 		SIMPLEQ_REMOVE_HEAD(&repo->objcache, entry);
287 		got_object_close(ce->obj);
288 		free(ce);
289 	}
290 
291 	free(repo->path);
292 	free(repo->path_git_dir);
293 	free(repo);
294 }