Update git-local-fetch documentation
[git] / tree.c
1 #include "cache.h"
2 #include "tree.h"
3 #include "blob.h"
4 #include "commit.h"
5 #include "tag.h"
6 #include "tree-walk.h"
7
8 const char *tree_type = "tree";
9
10 static int read_one_entry(const unsigned char *sha1, const char *base, int baselen, const char *pathname, unsigned mode, int stage)
11 {
12         int len;
13         unsigned int size;
14         struct cache_entry *ce;
15
16         if (S_ISDIR(mode))
17                 return READ_TREE_RECURSIVE;
18
19         len = strlen(pathname);
20         size = cache_entry_size(baselen + len);
21         ce = xcalloc(1, size);
22
23         ce->ce_mode = create_ce_mode(mode);
24         ce->ce_flags = create_ce_flags(baselen + len, stage);
25         memcpy(ce->name, base, baselen);
26         memcpy(ce->name + baselen, pathname, len+1);
27         hashcpy(ce->sha1, sha1);
28         return add_cache_entry(ce, ADD_CACHE_OK_TO_ADD|ADD_CACHE_SKIP_DFCHECK);
29 }
30
31 static int match_tree_entry(const char *base, int baselen, const char *path, unsigned int mode, const char **paths)
32 {
33         const char *match;
34         int pathlen;
35
36         if (!paths)
37                 return 1;
38         pathlen = strlen(path);
39         while ((match = *paths++) != NULL) {
40                 int matchlen = strlen(match);
41
42                 if (baselen >= matchlen) {
43                         /* If it doesn't match, move along... */
44                         if (strncmp(base, match, matchlen))
45                                 continue;
46                         /* The base is a subdirectory of a path which was specified. */
47                         return 1;
48                 }
49
50                 /* Does the base match? */
51                 if (strncmp(base, match, baselen))
52                         continue;
53
54                 match += baselen;
55                 matchlen -= baselen;
56
57                 if (pathlen > matchlen)
58                         continue;
59
60                 if (matchlen > pathlen) {
61                         if (match[pathlen] != '/')
62                                 continue;
63                         if (!S_ISDIR(mode))
64                                 continue;
65                 }
66
67                 if (strncmp(path, match, pathlen))
68                         continue;
69
70                 return 1;
71         }
72         return 0;
73 }
74
75 int read_tree_recursive(struct tree *tree,
76                         const char *base, int baselen,
77                         int stage, const char **match,
78                         read_tree_fn_t fn)
79 {
80         struct tree_desc desc;
81         struct name_entry entry;
82
83         if (parse_tree(tree))
84                 return -1;
85
86         init_tree_desc(&desc, tree->buffer, tree->size);
87
88         while (tree_entry(&desc, &entry)) {
89                 if (!match_tree_entry(base, baselen, entry.path, entry.mode, match))
90                         continue;
91
92                 switch (fn(entry.sha1, base, baselen, entry.path, entry.mode, stage)) {
93                 case 0:
94                         continue;
95                 case READ_TREE_RECURSIVE:
96                         break;;
97                 default:
98                         return -1;
99                 }
100                 if (S_ISDIR(entry.mode)) {
101                         int retval;
102                         char *newbase;
103                         unsigned int pathlen = tree_entry_len(entry.path, entry.sha1);
104
105                         newbase = xmalloc(baselen + 1 + pathlen);
106                         memcpy(newbase, base, baselen);
107                         memcpy(newbase + baselen, entry.path, pathlen);
108                         newbase[baselen + pathlen] = '/';
109                         retval = read_tree_recursive(lookup_tree(entry.sha1),
110                                                      newbase,
111                                                      baselen + pathlen + 1,
112                                                      stage, match, fn);
113                         free(newbase);
114                         if (retval)
115                                 return -1;
116                         continue;
117                 }
118         }
119         return 0;
120 }
121
122 int read_tree(struct tree *tree, int stage, const char **match)
123 {
124         return read_tree_recursive(tree, "", 0, stage, match, read_one_entry);
125 }
126
127 struct tree *lookup_tree(const unsigned char *sha1)
128 {
129         struct object *obj = lookup_object(sha1);
130         if (!obj) {
131                 struct tree *ret = alloc_tree_node();
132                 created_object(sha1, &ret->object);
133                 ret->object.type = OBJ_TREE;
134                 return ret;
135         }
136         if (!obj->type)
137                 obj->type = OBJ_TREE;
138         if (obj->type != OBJ_TREE) {
139                 error("Object %s is a %s, not a tree",
140                       sha1_to_hex(sha1), typename(obj->type));
141                 return NULL;
142         }
143         return (struct tree *) obj;
144 }
145
146 static void track_tree_refs(struct tree *item)
147 {
148         int n_refs = 0, i;
149         struct object_refs *refs;
150         struct tree_desc desc;
151         struct name_entry entry;
152
153         /* Count how many entries there are.. */
154         init_tree_desc(&desc, item->buffer, item->size);
155         while (tree_entry(&desc, &entry))
156                 n_refs++;
157
158         /* Allocate object refs and walk it again.. */
159         i = 0;
160         refs = alloc_object_refs(n_refs);
161         init_tree_desc(&desc, item->buffer, item->size);
162         while (tree_entry(&desc, &entry)) {
163                 struct object *obj;
164
165                 if (S_ISDIR(entry.mode))
166                         obj = &lookup_tree(entry.sha1)->object;
167                 else
168                         obj = &lookup_blob(entry.sha1)->object;
169                 refs->ref[i++] = obj;
170         }
171         set_object_refs(&item->object, refs);
172 }
173
174 int parse_tree_buffer(struct tree *item, void *buffer, unsigned long size)
175 {
176         if (item->object.parsed)
177                 return 0;
178         item->object.parsed = 1;
179         item->buffer = buffer;
180         item->size = size;
181
182         if (track_object_refs)
183                 track_tree_refs(item);
184         return 0;
185 }
186
187 int parse_tree(struct tree *item)
188 {
189          enum object_type type;
190          void *buffer;
191          unsigned long size;
192
193         if (item->object.parsed)
194                 return 0;
195         buffer = read_sha1_file(item->object.sha1, &type, &size);
196         if (!buffer)
197                 return error("Could not read %s",
198                              sha1_to_hex(item->object.sha1));
199         if (type != OBJ_TREE) {
200                 free(buffer);
201                 return error("Object %s not a tree",
202                              sha1_to_hex(item->object.sha1));
203         }
204         return parse_tree_buffer(item, buffer, size);
205 }
206
207 struct tree *parse_tree_indirect(const unsigned char *sha1)
208 {
209         struct object *obj = parse_object(sha1);
210         do {
211                 if (!obj)
212                         return NULL;
213                 if (obj->type == OBJ_TREE)
214                         return (struct tree *) obj;
215                 else if (obj->type == OBJ_COMMIT)
216                         obj = &(((struct commit *) obj)->tree->object);
217                 else if (obj->type == OBJ_TAG)
218                         obj = ((struct tag *) obj)->tagged;
219                 else
220                         return NULL;
221                 if (!obj->parsed)
222                         parse_object(obj->sha1);
223         } while (1);
224 }