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[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         desc.buf = tree->buffer;
87         desc.size = tree->size;
88
89         while (tree_entry(&desc, &entry)) {
90                 if (!match_tree_entry(base, baselen, entry.path, entry.mode, match))
91                         continue;
92
93                 switch (fn(entry.sha1, base, baselen, entry.path, entry.mode, stage)) {
94                 case 0:
95                         continue;
96                 case READ_TREE_RECURSIVE:
97                         break;;
98                 default:
99                         return -1;
100                 }
101                 if (S_ISDIR(entry.mode)) {
102                         int retval;
103                         char *newbase;
104
105                         newbase = xmalloc(baselen + 1 + entry.pathlen);
106                         memcpy(newbase, base, baselen);
107                         memcpy(newbase + baselen, entry.path, entry.pathlen);
108                         newbase[baselen + entry.pathlen] = '/';
109                         retval = read_tree_recursive(lookup_tree(entry.sha1),
110                                                      newbase,
111                                                      baselen + entry.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         desc.buf = item->buffer;
155         desc.size = item->size;
156         while (desc.size) {
157                 n_refs++;
158                 update_tree_entry(&desc);
159         }
160
161         /* Allocate object refs and walk it again.. */
162         i = 0;
163         refs = alloc_object_refs(n_refs);
164         desc.buf = item->buffer;
165         desc.size = item->size;
166         while (tree_entry(&desc, &entry)) {
167                 struct object *obj;
168
169                 if (S_ISDIR(entry.mode))
170                         obj = &lookup_tree(entry.sha1)->object;
171                 else
172                         obj = &lookup_blob(entry.sha1)->object;
173                 refs->ref[i++] = obj;
174         }
175         set_object_refs(&item->object, refs);
176 }
177
178 int parse_tree_buffer(struct tree *item, void *buffer, unsigned long size)
179 {
180         if (item->object.parsed)
181                 return 0;
182         item->object.parsed = 1;
183         item->buffer = buffer;
184         item->size = size;
185
186         if (track_object_refs)
187                 track_tree_refs(item);
188         return 0;
189 }
190
191 int parse_tree(struct tree *item)
192 {
193          char type[20];
194          void *buffer;
195          unsigned long size;
196
197         if (item->object.parsed)
198                 return 0;
199         buffer = read_sha1_file(item->object.sha1, type, &size);
200         if (!buffer)
201                 return error("Could not read %s",
202                              sha1_to_hex(item->object.sha1));
203         if (strcmp(type, tree_type)) {
204                 free(buffer);
205                 return error("Object %s not a tree",
206                              sha1_to_hex(item->object.sha1));
207         }
208         return parse_tree_buffer(item, buffer, size);
209 }
210
211 struct tree *parse_tree_indirect(const unsigned char *sha1)
212 {
213         struct object *obj = parse_object(sha1);
214         do {
215                 if (!obj)
216                         return NULL;
217                 if (obj->type == OBJ_TREE)
218                         return (struct tree *) obj;
219                 else if (obj->type == OBJ_COMMIT)
220                         obj = &(((struct commit *) obj)->tree->object);
221                 else if (obj->type == OBJ_TAG)
222                         obj = ((struct tag *) obj)->tagged;
223                 else
224                         return NULL;
225                 if (!obj->parsed)
226                         parse_object(obj->sha1);
227         } while (1);
228 }