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 #include "got_lib_object_idset.h"
41 
42 #ifndef nitems
43 #define nitems(_a) (sizeof(_a) / sizeof((_a)[0]))
44 #endif
45 
46 #define GOT_GIT_DIR	".git"
47 
48 /* Mandatory files and directories inside the git directory. */
49 #define GOT_OBJECTS_DIR		"objects"
50 #define GOT_REFS_DIR		"refs"
51 #define GOT_HEAD_FILE		"HEAD"
52 
53 /* Other files and directories inside the git directory. */
54 #define GOT_FETCH_HEAD_FILE	"FETCH_HEAD"
55 #define GOT_ORIG_HEAD_FILE	"ORIG_HEAD"
56 #define GOT_OBJECTS_PACK_DIR	"objects/pack"
57 
58 char *
59 got_repo_get_path(struct got_repository *repo)
60 {
61 	return strdup(repo->path);
62 }
63 
64 char *
65 got_repo_get_path_git_dir(struct got_repository *repo)
66 {
67 	return strdup(repo->path_git_dir);
68 }
69 
70 static char *
71 get_path_git_child(struct got_repository *repo, const char *basename)
72 {
73 	char *path_child;
74 	
75 	if (asprintf(&path_child, "%s/%s", repo->path_git_dir,
76 	    basename) == -1)
77 		return NULL;
78 
79 	return path_child;
80 }
81 
82 char *
83 got_repo_get_path_objects(struct got_repository *repo)
84 {
85 	return get_path_git_child(repo, GOT_OBJECTS_DIR);
86 }
87 
88 char *
89 got_repo_get_path_objects_pack(struct got_repository *repo)
90 {
91 	return get_path_git_child(repo, GOT_OBJECTS_PACK_DIR);
92 }
93 
94 char *
95 got_repo_get_path_refs(struct got_repository *repo)
96 {
97 	return get_path_git_child(repo, GOT_REFS_DIR);
98 }
99 
100 static char *
101 get_path_head(struct got_repository *repo)
102 {
103 	return get_path_git_child(repo, GOT_HEAD_FILE);
104 }
105 
106 static int
107 is_git_repo(struct got_repository *repo)
108 {
109 	char *path_git = got_repo_get_path_git_dir(repo);
110 	char *path_objects = got_repo_get_path_objects(repo);
111 	char *path_refs = got_repo_get_path_refs(repo);
112 	char *path_head = get_path_head(repo);
113 	int ret = 0;
114 	struct stat sb;
115 	struct got_reference *head_ref;
116 
117 	if (lstat(path_git, &sb) == -1)
118 		goto done;
119 	if (!S_ISDIR(sb.st_mode))
120 		goto done;
121 
122 	if (lstat(path_objects, &sb) == -1)
123 		goto done;
124 	if (!S_ISDIR(sb.st_mode))
125 		goto done;
126 
127 	if (lstat(path_refs, &sb) == -1)
128 		goto done;
129 	if (!S_ISDIR(sb.st_mode))
130 		goto done;
131 
132 	if (lstat(path_head, &sb) == -1)
133 		goto done;
134 	if (!S_ISREG(sb.st_mode))
135 		goto done;
136 
137 	/* Check if the HEAD reference can be opened. */
138 	if (got_ref_open(&head_ref, repo, GOT_REF_HEAD) != NULL)
139 		goto done;
140 	got_ref_close(head_ref);
141 
142 	ret = 1;
143 done:
144 	free(path_git);
145 	free(path_objects);
146 	free(path_refs);
147 	free(path_head);
148 	return ret;
149 
150 }
151 
152 const struct got_error *
153 got_repo_cache_object(struct got_repository *repo, struct got_object_id *id,
154     struct got_object *obj)
155 {
156 	const struct got_error *err = NULL;
157 	struct got_objcache_entry *ce;
158 
159 	if (repo->ncached >= GOT_OBJECT_CACHE_SIZE) {
160 		err = got_object_idset_remove_random((void **)&ce,
161 		    repo->objcache);
162 		if (err)
163 			return err;
164 		got_object_close(ce->obj);
165 		free(ce);
166 		repo->ncached--;
167 	}
168 
169 	ce = calloc(1, sizeof(*ce));
170 	if (ce == NULL)
171 		return got_error_from_errno();
172 	memcpy(&ce->id, id, sizeof(ce->id));
173 	ce->obj = obj;
174 	err = got_object_idset_add(NULL, repo->objcache, id, ce);
175 	if (err) {
176 		if (err->code == GOT_ERR_OBJ_EXISTS) {
177 			free(ce);
178 			err = NULL;
179 		}
180 	} else {
181 		obj->refcnt++;
182 		repo->ncached++;
183 	}
184 
185 	return err;
186 }
187 
188 struct got_object *
189 got_repo_get_cached_object(struct got_repository *repo,
190     struct got_object_id *id)
191 {
192 	struct got_objcache_entry *ce;
193 
194 	ce = got_object_idset_get(repo->objcache, id);
195 	if (ce) {
196 		repo->cache_hit++;
197 		return ce->obj;
198 	}
199 	repo->cache_miss++;
200 	return NULL;
201 }
202 
203 const struct got_error *
204 got_repo_open(struct got_repository **ret, const char *path)
205 {
206 	struct got_repository *repo = NULL;
207 	const struct got_error *err = NULL;
208 	char *abspath;
209 
210 	if (got_path_is_absolute(path))
211 		abspath = strdup(path);
212 	else
213 		abspath = got_path_get_absolute(path);
214 	if (abspath == NULL)
215 		return got_error(GOT_ERR_BAD_PATH);
216 
217 	repo = calloc(1, sizeof(*repo));
218 	if (repo == NULL) {
219 		err = got_error_from_errno();
220 		goto done;
221 	}
222 
223 	repo->objcache = got_object_idset_alloc();
224 	if (repo->objcache == NULL) {
225 		err = got_error_from_errno();
226 		goto done;
227 	}
228 
229 	repo->path = got_path_normalize(abspath);
230 	if (repo->path == NULL) {
231 		err = got_error(GOT_ERR_BAD_PATH);
232 		goto done;
233 	}
234 
235 	repo->path_git_dir = strdup(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, "%s/%s", repo->path,
243 		    GOT_GIT_DIR) == -1) {
244 			err = got_error_from_errno();
245 			goto done;
246 		}
247 		if (!is_git_repo(repo)) {
248 			struct got_worktree *worktree;
249 			if (got_worktree_open(&worktree, repo->path) == NULL) {
250 				free(repo->path_git_dir);
251 				repo->path_git_dir =
252 				    strdup(worktree->repo_path);
253 				if (repo->path_git_dir == NULL) {
254 					err = got_error_from_errno();
255 					goto done;
256 				}
257 				if (!is_git_repo(repo)) {
258 					free(repo->path_git_dir);
259 					if (asprintf(&repo->path_git_dir,
260 					    "%s/%s", worktree->repo_path,
261 					    GOT_GIT_DIR) == -1) {
262 						err = got_error_from_errno();
263 						goto done;
264 					}
265 				}
266 				got_worktree_close(worktree);
267 			}
268 		}
269 		if (!is_git_repo(repo)) {
270 			err = got_error(GOT_ERR_NOT_GIT_REPO);
271 			goto done;
272 		}
273 	}
274 		
275 	*ret = repo;
276 done:
277 	if (err)
278 		got_repo_close(repo);
279 	free(abspath);
280 	return err;
281 }
282 
283 void
284 got_repo_close(struct got_repository *repo)
285 {
286 	int i;
287 
288 	for (i = 0; i < nitems(repo->packidx_cache); i++) {
289 		if (repo->packidx_cache[i] == NULL)
290 			break;
291 		got_packidx_close(repo->packidx_cache[i]);
292 	}
293 
294 	for (i = 0; i < nitems(repo->packs); i++) {
295 		if (repo->packs[i].path_packfile == NULL)
296 			break;
297 		got_pack_close(&repo->packs[i]);
298 	}
299 
300 	free(repo->path);
301 	free(repo->path_git_dir);
302 	if (repo->objcache)
303 		got_object_idset_free(repo->objcache);
304 	free(repo);
305 }