tgupdate: merge girocco base into girocco
[git/gitweb.git] / name-hash.c
blob6d9f23e932559c58c9ebf4679a6035889f726ed2
1 /*
2 * name-hash.c
4 * Hashing names in the index state
6 * Copyright (C) 2008 Linus Torvalds
7 */
8 #define NO_THE_INDEX_COMPATIBILITY_MACROS
9 #include "cache.h"
11 struct dir_entry {
12 struct hashmap_entry ent;
13 struct dir_entry *parent;
14 int nr;
15 unsigned int namelen;
16 char name[FLEX_ARRAY];
19 static int dir_entry_cmp(const struct dir_entry *e1,
20 const struct dir_entry *e2, const char *name)
22 return e1->namelen != e2->namelen || strncasecmp(e1->name,
23 name ? name : e2->name, e1->namelen);
26 static struct dir_entry *find_dir_entry(struct index_state *istate,
27 const char *name, unsigned int namelen)
29 struct dir_entry key;
30 hashmap_entry_init(&key, memihash(name, namelen));
31 key.namelen = namelen;
32 return hashmap_get(&istate->dir_hash, &key, name);
35 static struct dir_entry *hash_dir_entry(struct index_state *istate,
36 struct cache_entry *ce, int namelen)
39 * Throw each directory component in the hash for quick lookup
40 * during a git status. Directory components are stored without their
41 * closing slash. Despite submodules being a directory, they never
42 * reach this point, because they are stored
43 * in index_state.name_hash (as ordinary cache_entries).
45 struct dir_entry *dir;
47 /* get length of parent directory */
48 while (namelen > 0 && !is_dir_sep(ce->name[namelen - 1]))
49 namelen--;
50 if (namelen <= 0)
51 return NULL;
52 namelen--;
54 /* lookup existing entry for that directory */
55 dir = find_dir_entry(istate, ce->name, namelen);
56 if (!dir) {
57 /* not found, create it and add to hash table */
58 FLEX_ALLOC_MEM(dir, name, ce->name, namelen);
59 hashmap_entry_init(dir, memihash(ce->name, namelen));
60 dir->namelen = namelen;
61 hashmap_add(&istate->dir_hash, dir);
63 /* recursively add missing parent directories */
64 dir->parent = hash_dir_entry(istate, ce, namelen);
66 return dir;
69 static void add_dir_entry(struct index_state *istate, struct cache_entry *ce)
71 /* Add reference to the directory entry (and parents if 0). */
72 struct dir_entry *dir = hash_dir_entry(istate, ce, ce_namelen(ce));
73 while (dir && !(dir->nr++))
74 dir = dir->parent;
77 static void remove_dir_entry(struct index_state *istate, struct cache_entry *ce)
80 * Release reference to the directory entry. If 0, remove and continue
81 * with parent directory.
83 struct dir_entry *dir = hash_dir_entry(istate, ce, ce_namelen(ce));
84 while (dir && !(--dir->nr)) {
85 struct dir_entry *parent = dir->parent;
86 hashmap_remove(&istate->dir_hash, dir, NULL);
87 free(dir);
88 dir = parent;
92 static void hash_index_entry(struct index_state *istate, struct cache_entry *ce)
94 if (ce->ce_flags & CE_HASHED)
95 return;
96 ce->ce_flags |= CE_HASHED;
97 hashmap_entry_init(ce, memihash(ce->name, ce_namelen(ce)));
98 hashmap_add(&istate->name_hash, ce);
100 if (ignore_case)
101 add_dir_entry(istate, ce);
104 static int cache_entry_cmp(const struct cache_entry *ce1,
105 const struct cache_entry *ce2, const void *remove)
108 * For remove_name_hash, find the exact entry (pointer equality); for
109 * index_file_exists, find all entries with matching hash code and
110 * decide whether the entry matches in same_name.
112 return remove ? !(ce1 == ce2) : 0;
115 static void lazy_init_name_hash(struct index_state *istate)
117 int nr;
119 if (istate->name_hash_initialized)
120 return;
121 hashmap_init(&istate->name_hash, (hashmap_cmp_fn) cache_entry_cmp,
122 istate->cache_nr);
123 hashmap_init(&istate->dir_hash, (hashmap_cmp_fn) dir_entry_cmp, 0);
124 for (nr = 0; nr < istate->cache_nr; nr++)
125 hash_index_entry(istate, istate->cache[nr]);
126 istate->name_hash_initialized = 1;
129 void add_name_hash(struct index_state *istate, struct cache_entry *ce)
131 if (istate->name_hash_initialized)
132 hash_index_entry(istate, ce);
135 void remove_name_hash(struct index_state *istate, struct cache_entry *ce)
137 if (!istate->name_hash_initialized || !(ce->ce_flags & CE_HASHED))
138 return;
139 ce->ce_flags &= ~CE_HASHED;
140 hashmap_remove(&istate->name_hash, ce, ce);
142 if (ignore_case)
143 remove_dir_entry(istate, ce);
146 static int slow_same_name(const char *name1, int len1, const char *name2, int len2)
148 if (len1 != len2)
149 return 0;
151 while (len1) {
152 unsigned char c1 = *name1++;
153 unsigned char c2 = *name2++;
154 len1--;
155 if (c1 != c2) {
156 c1 = toupper(c1);
157 c2 = toupper(c2);
158 if (c1 != c2)
159 return 0;
162 return 1;
165 static int same_name(const struct cache_entry *ce, const char *name, int namelen, int icase)
167 int len = ce_namelen(ce);
170 * Always do exact compare, even if we want a case-ignoring comparison;
171 * we do the quick exact one first, because it will be the common case.
173 if (len == namelen && !memcmp(name, ce->name, len))
174 return 1;
176 if (!icase)
177 return 0;
179 return slow_same_name(name, namelen, ce->name, len);
182 int index_dir_exists(struct index_state *istate, const char *name, int namelen)
184 struct dir_entry *dir;
186 lazy_init_name_hash(istate);
187 dir = find_dir_entry(istate, name, namelen);
188 return dir && dir->nr;
191 void adjust_dirname_case(struct index_state *istate, char *name)
193 const char *startPtr = name;
194 const char *ptr = startPtr;
196 lazy_init_name_hash(istate);
197 while (*ptr) {
198 while (*ptr && *ptr != '/')
199 ptr++;
201 if (*ptr == '/') {
202 struct dir_entry *dir;
204 ptr++;
205 dir = find_dir_entry(istate, name, ptr - name + 1);
206 if (dir) {
207 memcpy((void *)startPtr, dir->name + (startPtr - name), ptr - startPtr);
208 startPtr = ptr;
214 struct cache_entry *index_file_exists(struct index_state *istate, const char *name, int namelen, int icase)
216 struct cache_entry *ce;
218 lazy_init_name_hash(istate);
220 ce = hashmap_get_from_hash(&istate->name_hash,
221 memihash(name, namelen), NULL);
222 while (ce) {
223 if (same_name(ce, name, namelen, icase))
224 return ce;
225 ce = hashmap_get_next(&istate->name_hash, ce);
227 return NULL;
230 void free_name_hash(struct index_state *istate)
232 if (!istate->name_hash_initialized)
233 return;
234 istate->name_hash_initialized = 0;
236 hashmap_free(&istate->name_hash, 0);
237 hashmap_free(&istate->dir_hash, 1);