diff options
| -rw-r--r-- | src/mesa/shader/slang/slang_utility.c | 125 |
1 files changed, 71 insertions, 54 deletions
diff --git a/src/mesa/shader/slang/slang_utility.c b/src/mesa/shader/slang/slang_utility.c index 54fcc8a2382..256d52455db 100644 --- a/src/mesa/shader/slang/slang_utility.c +++ b/src/mesa/shader/slang/slang_utility.c @@ -131,75 +131,92 @@ slang_string_cstr (slang_string *self) /* slang_atom_pool */ -void slang_atom_pool_construct (slang_atom_pool *pool) +void +slang_atom_pool_construct(slang_atom_pool * pool) { - GLuint i; + GLuint i; - for (i = 0; i < SLANG_ATOM_POOL_SIZE; i++) - pool->entries[i] = NULL; + for (i = 0; i < SLANG_ATOM_POOL_SIZE; i++) + pool->entries[i] = NULL; } -void slang_atom_pool_destruct (slang_atom_pool *pool) +void +slang_atom_pool_destruct (slang_atom_pool * pool) { - GLuint i; + GLuint i; - for (i = 0; i < SLANG_ATOM_POOL_SIZE; i++) - { - slang_atom_entry *entry; + for (i = 0; i < SLANG_ATOM_POOL_SIZE; i++) { + slang_atom_entry * entry; - entry = pool->entries[i]; - while (entry != NULL) - { - slang_atom_entry *next; - - next = entry->next; - slang_alloc_free (entry->id); - slang_alloc_free (entry); - entry = next; + entry = pool->entries[i]; + while (entry != NULL) { + slang_atom_entry *next; + + next = entry->next; + slang_alloc_free(entry->id); + slang_alloc_free(entry); + entry = next; } } } -slang_atom slang_atom_pool_atom (slang_atom_pool *pool, const char *id) +/* + * Search the atom pool for an atom with a given name. + * If atom is not found, create and add it to the pool. + * Returns ATOM_NULL if the atom was not found and the function failed to create a new atom. + */ +slang_atom +slang_atom_pool_atom(slang_atom_pool * pool, const char * id) { - GLuint hash; - const char *p = id; - slang_atom_entry **entry; - - hash = 0; - while (*p != '\0') - { - GLuint g; - - hash = (hash << 4) + (GLuint) *p++; - g = hash & 0xf0000000; - if (g != 0) - hash ^= g >> 24; - hash &= ~g; - } - hash %= SLANG_ATOM_POOL_SIZE; - - entry = &pool->entries[hash]; - while (*entry != NULL) - { - if (slang_string_compare ((**entry).id, id) == 0) - return (slang_atom) (**entry).id; - entry = &(**entry).next; - } - - *entry = (slang_atom_entry *) slang_alloc_malloc (sizeof (slang_atom_entry)); - if (*entry == NULL) - return SLANG_ATOM_NULL; + GLuint hash; + const char * p = id; + slang_atom_entry ** entry; + + /* Hash a given string to a number in the range [0, ATOM_POOL_SIZE). */ + hash = 0; + while (*p != '\0') { + GLuint g; + + hash = (hash << 4) + (GLuint) (*p++); + g = hash & 0xf0000000; + if (g != 0) + hash ^= g >> 24; + hash &= ~g; + } + hash %= SLANG_ATOM_POOL_SIZE; + + /* Now the hash points to a linked list of atoms with names that have the same hash value. + * Search the linked list for a given name. */ + entry = &pool->entries[hash]; + while (*entry != NULL) { + /* If the same, return the associated atom. */ + if (slang_string_compare((**entry).id, id) == 0) + return (slang_atom) (**entry).id; + /* Grab the next atom in the linked list. */ + entry = &(**entry).next; + } - (**entry).next = NULL; - (**entry).id = slang_string_duplicate (id); - if ((**entry).id == NULL) - return SLANG_ATOM_NULL; - return (slang_atom) (**entry).id; + /* Okay, we have not found an atom. Create a new entry for it. + * Note that the <entry> points to the last entry's <next> field. */ + *entry = (slang_atom_entry *) (slang_alloc_malloc(sizeof(slang_atom_entry))); + if (*entry == NULL) + return SLANG_ATOM_NULL; + + /* Initialize a new entry. Because we'll need the actual name of the atom, we use the pointer + * to this string as an actual atom's value. */ + (**entry).next = NULL; + (**entry).id = slang_string_duplicate(id); + if ((**entry).id == NULL) + return SLANG_ATOM_NULL; + return (slang_atom) (**entry).id; } -const char *slang_atom_pool_id (slang_atom_pool *pool, slang_atom atom) +/* + * Return the name of a given atom. + */ +const char * +slang_atom_pool_id(slang_atom_pool * pool, slang_atom atom) { - return (const char *) atom; + return (const char *) (atom); } |