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/stat.h>
18 
19 #include <string.h>
20 #include <stdio.h>
21 #include <stdlib.h>
22 #include <fcntl.h>
23 #include <errno.h>
24 #include <unistd.h>
25 
26 #include "got_error.h"
27 #include "got_repository.h"
28 #include "got_refs.h"
29 #include "got_worktree.h"
30 
31 #include "got_worktree_priv.h"
32 #include "got_path_priv.h"
33 
34 static const struct got_error *
35 create_meta_file(const char *gotpath, const char *name, const char *content)
36 {
37 	const struct got_error *err = NULL;
38 	char *path;
39 	int fd = -1;
40 	char buf[4];
41 	ssize_t n;
42 
43 	if (asprintf(&path, "%s/%s", gotpath, name) == -1) {
44 		err = got_error(GOT_ERR_NO_MEM);
45 		path = NULL;
46 		goto done;
47 	}
48 
49 	fd = open(path, O_RDWR | O_CREAT | O_EXCL | O_EXLOCK | O_NOFOLLOW,
50 	    GOT_DEFAULT_FILE_MODE);
51 	if (fd == -1) {
52 		err = got_error_from_errno();
53 		goto done;
54 	}
55 
56 	/* The file should be empty. */
57 	n = read(fd, buf, sizeof(buf));
58 	if (n != 0) {
59 		err = (n == -1 ? got_error_from_errno() :
60 		    got_error(GOT_ERR_WORKTREE_EXISTS));
61 		goto done;
62 	}
63 
64 	if (content) {
65 		int len = dprintf(fd, "%s\n", content);
66 		if (len != strlen(content) + 1) {
67 			err = got_error_from_errno();
68 			goto done;
69 		}
70 	}
71 
72 done:
73 	if (fd != -1 && close(fd) == -1 && err == NULL)
74 		err = got_error_from_errno();
75 	free(path);
76 	return err;
77 }
78 
79 const struct got_error *
80 got_worktree_init(const char *path, struct got_reference *head_ref,
81     const char *prefix, struct got_repository *repo)
82 {
83 	const struct got_error *err = NULL;
84 	char *abspath = NULL;
85 	char *normpath = NULL;
86 	char *gotpath = NULL;
87 	char *refstr = NULL;
88 	char *path_repos = NULL;
89 	char *formatstr = NULL;
90 
91 	if (!got_path_is_absolute(prefix))
92 		return got_error(GOT_ERR_BAD_PATH);
93 
94 	if (got_path_is_absolute(path)) {
95 		abspath = strdup(path);
96 		if (abspath == NULL)
97 			return got_error(GOT_ERR_NO_MEM);
98 	} else {
99 		abspath = got_path_get_absolute(path);
100 		if (abspath == NULL)
101 			return got_error(GOT_ERR_BAD_PATH);
102 	}
103 
104 	/* Create top-level directory (may already exist). */
105 	normpath = got_path_normalize(abspath);
106 	if (normpath == NULL) {
107 		err = got_error(GOT_ERR_BAD_PATH);
108 		goto done;
109 	}
110 	if (mkdir(normpath, GOT_DEFAULT_DIR_MODE) == -1 && errno != EEXIST) {
111 		err = got_error_from_errno();
112 		goto done;
113 	}
114 
115 	/* Create .got directory (may already exist). */
116 	if (asprintf(&gotpath, "%s/%s", normpath, GOT_WORKTREE_GOT_DIR) == -1) {
117 		err = got_error(GOT_ERR_NO_MEM);
118 		goto done;
119 	}
120 	if (mkdir(gotpath, GOT_DEFAULT_DIR_MODE) == -1 && errno != EEXIST) {
121 		err = got_error_from_errno();
122 		goto done;
123 	}
124 
125 	/* Create an empty file index. */
126 	err = create_meta_file(gotpath, GOT_WORKTREE_FILE_INDEX, NULL);
127 	if (err)
128 		goto done;
129 
130 	/* Write the HEAD reference. */
131 	refstr = got_ref_to_str(head_ref);
132 	if (refstr == NULL) {
133 		err = got_error(GOT_ERR_NO_MEM);
134 		goto done;
135 	}
136 	err = create_meta_file(gotpath, GOT_REF_HEAD, refstr);
137 	if (err)
138 		goto done;
139 
140 	/* Store path to repository. */
141 	path_repos = got_repo_get_path(repo);
142 	if (path_repos == NULL) {
143 		err = got_error(GOT_ERR_NO_MEM);
144 		goto done;
145 	}
146 	err = create_meta_file(gotpath, GOT_WORKTREE_REPOSITORY, path_repos);
147 	if (err)
148 		goto done;
149 
150 	/* Store in-repository path prefix. */
151 	err = create_meta_file(gotpath, GOT_WORKTREE_PATH_PREFIX, prefix);
152 	if (err)
153 		goto done;
154 
155 	/* Stamp work tree with format file. */
156 	if (asprintf(&formatstr, "%d", GOT_WORKTREE_FORMAT_VERSION) == -1) {
157 		err = got_error(GOT_ERR_NO_MEM);
158 		goto done;
159 	}
160 	err = create_meta_file(gotpath, GOT_WORKTREE_FORMAT, formatstr);
161 	if (err)
162 		goto done;
163 
164 done:
165 	free(abspath);
166 	free(normpath);
167 	free(gotpath);
168 	free(formatstr);
169 	free(refstr);
170 	free(path_repos);
171 	return err;
172 }
173 
174 const struct got_error *
175 got_worktree_open(struct got_worktree **worktree, const char *path)
176 {
177 	return NULL;
178 }
179 
180 void
181 got_worktree_close(struct got_worktree *worktree)
182 {
183 }
184 
185 char *
186 got_worktree_get_repo_path(struct got_worktree *worktree)
187 {
188 	return strdup(worktree->path_repo);
189 }
190 
191 struct got_reference *
192 got_worktree_get_head(struct got_worktree *worktree)
193 {
194 	return NULL;
195 }
196 
197 const struct got_error *
198 got_worktree_set_head(struct got_worktree *worktree, struct got_reference *head,
199     struct got_repository *repo)
200 {
201 	return NULL;
202 }
203 
204 const struct got_error *
205 got_worktree_checkout_files(struct got_worktree *worktree,
206     struct got_repository *repo)
207 {
208 	return NULL;
209 }