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 
31 #include "got_lib_path.h"
32 #include "got_lib_delta.h"
33 #include "got_lib_zbuf.h"
34 #include "got_lib_object.h"
35 #include "got_lib_pack.h"
36 #include "got_lib_repository.h"
37 
38 #ifndef nitems
39 #define nitems(_a) (sizeof(_a) / sizeof((_a)[0]))
40 #endif
41 
42 #define GOT_GIT_DIR	".git"
43 
44 /* Mandatory files and directories inside the git directory. */
45 #define GOT_OBJECTS_DIR		"objects"
46 #define GOT_REFS_DIR		"refs"
47 #define GOT_HEAD_FILE		"HEAD"
48 
49 /* Other files and directories inside the git directory. */
50 #define GOT_FETCH_HEAD_FILE	"FETCH_HEAD"
51 #define GOT_ORIG_HEAD_FILE	"ORIG_HEAD"
52 #define GOT_OBJECTS_PACK_DIR	"objects/pack"
53 
54 char *
55 got_repo_get_path(struct got_repository *repo)
56 {
57 	return strdup(repo->path);
58 }
59 
60 char *
61 got_repo_get_path_git_dir(struct got_repository *repo)
62 {
63 	return strdup(repo->path_git_dir);
64 }
65 
66 static char *
67 get_path_git_child(struct got_repository *repo, const char *basename)
68 {
69 	char *path_child;
70 	
71 	if (asprintf(&path_child, "%s/%s", repo->path_git_dir,
72 	    basename) == -1)
73 		return NULL;
74 
75 	return path_child;
76 }
77 
78 char *
79 got_repo_get_path_objects(struct got_repository *repo)
80 {
81 	return get_path_git_child(repo, GOT_OBJECTS_DIR);
82 }
83 
84 char *
85 got_repo_get_path_objects_pack(struct got_repository *repo)
86 {
87 	return get_path_git_child(repo, GOT_OBJECTS_PACK_DIR);
88 }
89 
90 char *
91 got_repo_get_path_refs(struct got_repository *repo)
92 {
93 	return get_path_git_child(repo, GOT_REFS_DIR);
94 }
95 
96 static char *
97 get_path_head(struct got_repository *repo)
98 {
99 	return get_path_git_child(repo, GOT_HEAD_FILE);
100 }
101 
102 static int
103 is_git_repo(struct got_repository *repo)
104 {
105 	char *path_git = got_repo_get_path_git_dir(repo);
106 	char *path_objects = got_repo_get_path_objects(repo);
107 	char *path_refs = got_repo_get_path_refs(repo);
108 	char *path_head = get_path_head(repo);
109 	int ret = 0;
110 	struct stat sb;
111 	struct got_reference *head_ref;
112 
113 	if (lstat(path_git, &sb) == -1)
114 		goto done;
115 	if (!S_ISDIR(sb.st_mode))
116 		goto done;
117 
118 	if (lstat(path_objects, &sb) == -1)
119 		goto done;
120 	if (!S_ISDIR(sb.st_mode))
121 		goto done;
122 
123 	if (lstat(path_refs, &sb) == -1)
124 		goto done;
125 	if (!S_ISDIR(sb.st_mode))
126 		goto done;
127 
128 	if (lstat(path_head, &sb) == -1)
129 		goto done;
130 	if (!S_ISREG(sb.st_mode))
131 		goto done;
132 
133 	/* Check if the HEAD reference can be opened. */
134 	if (got_ref_open(&head_ref, repo, GOT_REF_HEAD) != NULL)
135 		goto done;
136 	got_ref_close(head_ref);
137 
138 	ret = 1;
139 done:
140 	free(path_git);
141 	free(path_objects);
142 	free(path_refs);
143 	free(path_head);
144 	return ret;
145 
146 }
147 
148 const struct got_error *
149 got_repo_open(struct got_repository **ret, const char *path)
150 {
151 	struct got_repository *repo = NULL;
152 	const struct got_error *err = NULL;
153 	char *abspath;
154 
155 	if (got_path_is_absolute(path))
156 		abspath = strdup(path);
157 	else
158 		abspath = got_path_get_absolute(path);
159 	if (abspath == NULL)
160 		return got_error(GOT_ERR_BAD_PATH);
161 
162 	repo = calloc(1, sizeof(*repo));
163 	if (repo == NULL) {
164 		err = got_error_from_errno();
165 		goto done;
166 	}
167 
168 	repo->path = got_path_normalize(abspath);
169 	if (repo->path == NULL) {
170 		err = got_error(GOT_ERR_BAD_PATH);
171 		goto done;
172 	}
173 
174 	repo->path_git_dir = strdup(repo->path);
175 	if (repo->path_git_dir == NULL) {
176 		err = got_error_from_errno();
177 		goto done;
178 	}
179 	if (!is_git_repo(repo)) {
180 		free(repo->path_git_dir);
181 		if (asprintf(&repo->path_git_dir, "%s/%s", repo->path,
182 		    GOT_GIT_DIR) == -1) {
183 			err = got_error_from_errno();
184 			goto done;
185 		}
186 		if (!is_git_repo(repo)) {
187 			err = got_error(GOT_ERR_NOT_GIT_REPO);
188 			goto done;
189 		}
190 	}
191 		
192 	*ret = repo;
193 done:
194 	if (err)
195 		got_repo_close(repo);
196 	free(abspath);
197 	return err;
198 }
199 
200 void
201 got_repo_close(struct got_repository *repo)
202 {
203 	int i;
204 
205 	for (i = 0; i < nitems(repo->packidx_cache); i++) {
206 		if (repo->packidx_cache[i] == NULL)
207 			break;
208 		got_packidx_close(repo->packidx_cache[i]);
209 	}
210 
211 	for (i = 0; i < nitems(repo->packs); i++) {
212 		if (repo->packs[i].path_packfile == NULL)
213 			break;
214 		got_pack_close(&repo->packs[i]);
215 	}
216 
217 	free(repo->path);
218 	free(repo->path_git_dir);
219 	free(repo);
220 }