1 /*
2  * Copyright (c) 2017 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 <assert.h>
18 #include <limits.h>
19 #include <stdlib.h>
20 #include <stdio.h>
21 #include <sha1.h>
22 #include <string.h>
23 
24 #include "got_path.h"
25 #include "got_error.h"
26 #include "got_refs.h"
27 #include "got_repository.h"
28 
29 #define GOT_GIT_DIR	".git"
30 
31 /* Mandatory files and directories inside the git directory. */
32 #define GOT_OBJECTS_DIR	"objects"
33 #define GOT_REFS_DIR	"refs"
34 #define GOT_HEAD_FILE	"HEAD"
35 
36 static char *
37 get_path_git_dir(struct got_repository *repo)
38 {
39 	char *path_git;
40 	
41 	if (asprintf(&path_git, "%s/%s", repo->path, GOT_GIT_DIR) == -1)
42 		return NULL;
43 
44 	return path_git;
45 }
46 
47 static char *
48 get_path_git_child(struct got_repository *repo, const char *basename)
49 {
50 	char *path_child;
51 	
52 	if (asprintf(&path_child, "%s/%s/%s", repo->path, GOT_GIT_DIR,
53 	    basename) == -1)
54 		return NULL;
55 
56 	return path_child;
57 }
58 
59 static char *
60 get_path_objects(struct got_repository *repo)
61 {
62 	return get_path_git_child(repo, GOT_OBJECTS_DIR);
63 }
64 
65 static char *
66 get_path_refs(struct got_repository *repo)
67 {
68 	return get_path_git_child(repo, GOT_REFS_DIR);
69 }
70 
71 static char *
72 get_path_head(struct got_repository *repo)
73 {
74 	return get_path_git_child(repo, GOT_HEAD_FILE);
75 }
76 
77 static int
78 is_git_repo(struct got_repository *repo)
79 {
80 	char *path_git = get_path_git_dir(repo);
81 	char *path_objects = get_path_objects(repo);
82 	char *path_refs = get_path_refs(repo);
83 	char *path_head = get_path_head(repo);
84 	int ret;
85 
86 	ret = (path_git != NULL) && (path_objects != NULL) &&
87 	    (path_refs != NULL) && (path_head != NULL);
88 
89 	free(path_git);
90 	free(path_objects);
91 	free(path_refs);
92 	free(path_head);
93 	return ret;
94 
95 }
96 
97 const struct got_error *
98 got_repo_open(struct got_repository **ret, const char *abspath)
99 {
100 	struct got_repository *repo;
101 
102 	if (!got_path_is_absolute(abspath))
103 		return got_error(GOT_ERR_NOT_ABSPATH);
104 
105 	repo = calloc(1, sizeof(*repo));
106 	if (repo == NULL)
107 		return got_error(GOT_ERR_NO_MEM);
108 
109 	repo->path = got_path_normalize(abspath);
110 	if (repo->path == NULL)
111 		return got_error(GOT_ERR_BAD_PATH);
112 
113 	if (!is_git_repo(repo))
114 		return got_error(GOT_ERR_NOT_GIT_REPO);
115 		
116 	*ret = repo;
117 	return NULL;
118 }
119 
120 void
121 got_repo_close(struct got_repository *repo)
122 {
123 	free(repo->path);
124 	free(repo);
125 }
126 
127 const char *
128 got_repo_get_path(struct got_repository *repo)
129 {
130 	return repo->path;
131 }
132 
133 const struct got_error *
134 got_repo_get_reference(struct got_reference **ref,
135     struct got_repository *repo, const char *refname)
136 {
137 	const struct got_error *err = NULL;
138 	char *path_refs;
139 
140 	/* Some refs live in the .git directory. */
141 	if (strcmp(refname, GOT_REF_HEAD) == 0)
142 		path_refs = get_path_git_dir(repo);
143 	else
144 		path_refs = get_path_refs(repo);
145 
146 	err = got_ref_open(ref, path_refs, refname);
147 	free(path_refs);
148 	return err;
149 }