branch: fix segfault when resolving an invalid HEAD
[git/jnareb-git.git] / tree.c
blobd188c0fbaee110a17ca7a0d16dcc979091f44ded
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"
8 const char *tree_type = "tree";
10 static int read_one_entry(const unsigned char *sha1, const char *base, int baselen, const char *pathname, unsigned mode, int stage)
12 int len;
13 unsigned int size;
14 struct cache_entry *ce;
16 if (S_ISDIR(mode))
17 return READ_TREE_RECURSIVE;
19 len = strlen(pathname);
20 size = cache_entry_size(baselen + len);
21 ce = xcalloc(1, size);
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);
31 static int match_tree_entry(const char *base, int baselen, const char *path, unsigned int mode, const char **paths)
33 const char *match;
34 int pathlen;
36 if (!paths)
37 return 1;
38 pathlen = strlen(path);
39 while ((match = *paths++) != NULL) {
40 int matchlen = strlen(match);
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;
50 /* Does the base match? */
51 if (strncmp(base, match, baselen))
52 continue;
54 match += baselen;
55 matchlen -= baselen;
57 if (pathlen > matchlen)
58 continue;
60 if (matchlen > pathlen) {
61 if (match[pathlen] != '/')
62 continue;
63 if (!S_ISDIR(mode))
64 continue;
67 if (strncmp(path, match, pathlen))
68 continue;
70 return 1;
72 return 0;
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)
80 struct tree_desc desc;
81 struct name_entry entry;
83 if (parse_tree(tree))
84 return -1;
86 init_tree_desc(&desc, tree->buffer, tree->size);
88 while (tree_entry(&desc, &entry)) {
89 if (!match_tree_entry(base, baselen, entry.path, entry.mode, match))
90 continue;
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;
100 if (S_ISDIR(entry.mode)) {
101 int retval;
102 char *newbase;
103 unsigned int pathlen = tree_entry_len(entry.path, entry.sha1);
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;
119 return 0;
122 int read_tree(struct tree *tree, int stage, const char **match)
124 return read_tree_recursive(tree, "", 0, stage, match, read_one_entry);
127 struct tree *lookup_tree(const unsigned char *sha1)
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;
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;
143 return (struct tree *) obj;
146 static void track_tree_refs(struct tree *item)
148 int n_refs = 0, i;
149 struct object_refs *refs;
150 struct tree_desc desc;
151 struct name_entry entry;
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++;
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;
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;
171 set_object_refs(&item->object, refs);
174 int parse_tree_buffer(struct tree *item, void *buffer, unsigned long size)
176 if (item->object.parsed)
177 return 0;
178 item->object.parsed = 1;
179 item->buffer = buffer;
180 item->size = size;
182 if (track_object_refs)
183 track_tree_refs(item);
184 return 0;
187 int parse_tree(struct tree *item)
189 enum object_type type;
190 void *buffer;
191 unsigned long size;
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));
204 return parse_tree_buffer(item, buffer, size);
207 struct tree *parse_tree_indirect(const unsigned char *sha1)
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);