From: Philip Prindeville philipp@fedoraproject.org
Add c_str as a "const char *" to the hash_key_t.
Redux per comments from Michal Zidek. --- dhash/dhash.c | 29 +++++++++++++++++++++-------- dhash/dhash.h | 4 +++- dhash/examples/dhash_test.c | 3 +++ 3 files changed, 27 insertions(+), 9 deletions(-)
diff --git a/dhash/dhash.c b/dhash/dhash.c index 45ee0cf..98439e8 100644 --- a/dhash/dhash.c +++ b/dhash/dhash.c @@ -176,7 +176,7 @@ static void sys_free_wrapper(void *ptr, void *pvt) static address_t convert_key(hash_key_t *key) { address_t h; - unsigned char *k; + const unsigned char *k;
switch(key->type) { case HASH_KEY_ULONG: @@ -184,7 +184,12 @@ static address_t convert_key(hash_key_t *key) break; case HASH_KEY_STRING: /* Convert string to integer */ - for (h = 0, k = (unsigned char *) key->str; *k; k++) + for (h = 0, k = (const unsigned char *) key->str; *k; k++) + h = h * PRIME_1 ^ (*k - ' '); + break; + case HASH_KEY_CONST_STRING: + /* Convert string to integer */ + for (h = 0, k = (const unsigned char *) key->c_str; *k; k++) h = h * PRIME_1 ^ (*k - ' '); break; default: @@ -212,6 +217,7 @@ static bool is_valid_key_type(hash_key_enum key_type) switch(key_type) { case HASH_KEY_ULONG: case HASH_KEY_STRING: + case HASH_KEY_CONST_STRING: return true; default: return false; @@ -244,6 +250,8 @@ static bool key_equal(hash_key_t *a, hash_key_t *b) return (a->ul == b->ul); case HASH_KEY_STRING: return (strcmp(a->str, b->str) == 0); + case HASH_KEY_CONST_STRING: + return (strcmp(a->c_str, b->c_str) == 0); } return false; } @@ -670,8 +678,11 @@ int hash_destroy(hash_table_t *table) while (p != NULL) { q = p->next; hdelete_callback(table, HASH_TABLE_DESTROY, &p->entry); - if (p->entry.key.type == HASH_KEY_STRING) { - hfree(table, (char *)p->entry.key.str); + if (p->entry.key.type == HASH_KEY_STRING + || p->entry.key.type == HASH_KEY_CONST_STRING) { + /* Internally we do not use constant memory for keys + * in hash table elements. */ + hfree(table, p->entry.key.str); } hfree(table, (char *)p); p = q; @@ -972,13 +983,14 @@ int hash_enter(hash_table_t *table, hash_key_t *key, hash_value_t *value) element->entry.key.ul = key->ul; break; case HASH_KEY_STRING: - len = strlen(key->str)+1; + case HASH_KEY_CONST_STRING: + len = strlen(key->c_str) + 1; element->entry.key.str = halloc(table, len); if (element->entry.key.str == NULL) { hfree(table, element); return HASH_ERROR_NO_MEMORY; } - memcpy((void *)element->entry.key.str, key->str, len); + memcpy(element->entry.key.str, key->str, len); break; }
@@ -1070,8 +1082,9 @@ int hash_delete(hash_table_t *table, hash_key_t *key) return error; } } - if (element->entry.key.type == HASH_KEY_STRING) { - hfree(table, (char *)element->entry.key.str); + if (element->entry.key.type == HASH_KEY_STRING + || element->entry.key.type == HASH_KEY_CONST_STRING) { + hfree(table, element->entry.key.str); } hfree(table, element); return HASH_SUCCESS; diff --git a/dhash/dhash.h b/dhash/dhash.h index baa0d6a..c36ab79 100644 --- a/dhash/dhash.h +++ b/dhash/dhash.h @@ -112,7 +112,8 @@ typedef struct hash_table_str hash_table_t;
typedef enum { HASH_KEY_STRING, - HASH_KEY_ULONG + HASH_KEY_ULONG, + HASH_KEY_CONST_STRING } hash_key_enum;
typedef enum @@ -137,6 +138,7 @@ typedef struct hash_key_t { hash_key_enum type; union { char *str; + const char *c_str; unsigned long ul; }; } hash_key_t; diff --git a/dhash/examples/dhash_test.c b/dhash/examples/dhash_test.c index 303e9f8..7613e23 100644 --- a/dhash/examples/dhash_test.c +++ b/dhash/examples/dhash_test.c @@ -64,6 +64,9 @@ static char *key_string(hash_key_t *key) case HASH_KEY_STRING: snprintf(buf, sizeof(buf), "key string = "%s"", key->str); break; + case HASH_KEY_CONST_STRING: + snprintf(buf, sizeof(buf), "key string = "%s"", key->c_str); + break; default: snprintf(buf, sizeof(buf), "unknown key type = %d", key->type); break;