diff options
Diffstat (limited to 'ubi-utils/src/hashmap.c')
-rw-r--r-- | ubi-utils/src/hashmap.c | 412 |
1 files changed, 412 insertions, 0 deletions
diff --git a/ubi-utils/src/hashmap.c b/ubi-utils/src/hashmap.c new file mode 100644 index 0000000..250f71f --- /dev/null +++ b/ubi-utils/src/hashmap.c @@ -0,0 +1,412 @@ +/* + * Copyright (c) International Business Machines Corp., 2006 + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See + * the GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + * + * Author: Oliver Lohmann + */ + +#include <errno.h> +#include <string.h> +#include <stdio.h> +#include <stdlib.h> +#include "error.h" +#include "hashmap.h" +#define DEFAULT_BUCKETS 4096 + +#if 0 +#define INFO_MSG(fmt...) do { \ + info_msg(fmt); \ +} while (0) +#else +#define INFO_MSG(fmt...) +#endif + +struct hashentry { + char* key; /* key '0' term. str */ + char* value; /* payload '0' term. str */ + + hashentry_t next; +}; + +struct hashmap { + size_t entries; /* current #entries */ + size_t maxsize; /* no. of hash buckets */ + hashentry_t* data; /* array of buckets */ +}; + +static int +is_empty(hashentry_t l) +{ + return l == NULL ? 1 : 0; +} + +hashmap_t +hashmap_new(void) +{ + hashmap_t res; + res = (hashmap_t) calloc(1, sizeof(struct hashmap)); + + if (res == NULL) + return NULL; + + res->maxsize = DEFAULT_BUCKETS; + res->entries = 0; + + res->data = (hashentry_t*) + calloc(1, res->maxsize * sizeof(struct hashentry)); + + if (res->data == NULL) + return NULL; + + return res; +} + +static hashentry_t +new_entry(const char* key, const char* value) +{ + hashentry_t res; + + res = (hashentry_t) calloc(1, sizeof(struct hashentry)); + + if (res == NULL) + return NULL; + + /* allocate key and value and copy them */ + res->key = strdup(key); + if (res->key == NULL) { + free(res); + return NULL; + } + + res->value = strdup(value); + if (res->value == NULL) { + free(res->key); + free(res); + return NULL; + } + + res->next = NULL; + + return res; +} + +static hashentry_t +free_entry(hashentry_t e) +{ + if (!is_empty(e)) { + if(e->key != NULL) { + free(e->key); + } + if(e->value != NULL) + free(e->value); + free(e); + } + + return NULL; +} + +static hashentry_t +remove_entry(hashentry_t l, const char* key, size_t* entries) +{ + hashentry_t lnext; + if (is_empty(l)) + return NULL; + + if(strcmp(l->key,key) == 0) { + lnext = l->next; + l = free_entry(l); + (*entries)--; + return lnext; + } + + l->next = remove_entry(l->next, key, entries); + + return l; +} + +static hashentry_t +insert_entry(hashentry_t l, hashentry_t e, size_t* entries) +{ + if (is_empty(l)) { + (*entries)++; + return e; + } + + /* check for update */ + if (strcmp(l->key, e->key) == 0) { + e->next = l->next; + l = free_entry(l); + return e; + } + + l->next = insert_entry(l->next, e, entries); + return l; +} + +static hashentry_t +remove_all(hashentry_t l, size_t* entries) +{ + hashentry_t lnext; + if (is_empty(l)) + return NULL; + + lnext = l->next; + free_entry(l); + (*entries)--; + + return remove_all(lnext, entries); +} + +static const char* +value_lookup(hashentry_t l, const char* key) +{ + if (is_empty(l)) + return NULL; + + if (strcmp(l->key, key) == 0) + return l->value; + + return value_lookup(l->next, key); +} + +static void +print_all(hashentry_t l) +{ + if (is_empty(l)) { + printf("\n"); + return; + } + + printf("%s=%s", l->key, l->value); + if (!is_empty(l->next)) { + printf(","); + } + + print_all(l->next); +} + +static void +keys_to_array(hashentry_t l, const char** a, size_t* i) +{ + if (is_empty(l)) + return; + + a[*i] = l->key; + (*i)++; + + keys_to_array(l->next, a, i); +} + +uint32_t +hash_str(const char* str, uint32_t mapsize) +{ + uint32_t hash = 0; + uint32_t x = 0; + uint32_t i = 0; + size_t len = strlen(str); + + for(i = 0; i < len; str++, i++) { + hash = (hash << 4) + (*str); + if((x = hash & 0xF0000000L) != 0) { + hash ^= (x >> 24); + hash &= ~x; + } + } + + return (hash & 0x7FFFFFFF) % mapsize; +} + + +int +hashmap_is_empty(hashmap_t map) +{ + if (map == NULL) + return -EINVAL; + + return map->entries > 0 ? 1 : 0; +} + +const char* +hashmap_lookup(hashmap_t map, const char* key) +{ + uint32_t i; + + if ((map == NULL) || (key == NULL)) + return NULL; + + i = hash_str(key, map->maxsize); + + return value_lookup(map->data[i], key); +} + +int +hashmap_add(hashmap_t map, const char* key, const char* value) +{ + uint32_t i; + hashentry_t entry; + + if ((map == NULL) || (key == NULL) || (value == NULL)) + return -EINVAL; + + i = hash_str(key, map->maxsize); + entry = new_entry(key, value); + if (entry == NULL) + return -ENOMEM; + + map->data[i] = insert_entry(map->data[i], + entry, &map->entries); + + INFO_MSG("HASH_ADD: chain[%d] key:%s val:%s",i, key, value); + return 0; +} + +int +hashmap_remove(hashmap_t map, const char* key) +{ + uint32_t i; + + if ((map == NULL) || (key == NULL)) + return -EINVAL; + + i = hash_str(key, map->maxsize); + map->data[i] = remove_entry(map->data[i], key, &map->entries); + + return 0; +} + +size_t +hashmap_size(hashmap_t map) +{ + if (map != NULL) + return map->entries; + else + return 0; +} + +int +hashmap_free(hashmap_t map) +{ + size_t i; + + if (map == NULL) + return -EINVAL; + + /* "children" first */ + for(i = 0; i < map->maxsize; i++) { + map->data[i] = remove_all(map->data[i], &map->entries); + } + free(map->data); + free(map); + + return 0; +} + +int +hashmap_dump(hashmap_t map) +{ + size_t i; + if (map == NULL) + return -EINVAL; + + for(i = 0; i < map->maxsize; i++) { + if (map->data[i] != NULL) { + printf("[%d]: ", i); + print_all(map->data[i]); + } + } + + return 0; +} + +static const char** +sort_key_vector(const char** a, size_t size) +{ + /* uses bubblesort */ + size_t i, j; + const char* tmp; + + if (size <= 0) + return a; + + for (i = size - 1; i > 0; i--) { + for (j = 0; j < i; j++) { + if (strcmp(a[j], a[j+1]) > 0) { + tmp = a[j]; + a[j] = a[j+1]; + a[j+1] = tmp; + } + } + } + return a; +} + +const char** +hashmap_get_key_vector(hashmap_t map, size_t* size, int sort) +{ + const char** res; + size_t i, j; + *size = map->entries; + + res = (const char**) malloc(*size * sizeof(char*)); + if (res == NULL) + return NULL; + + j = 0; + for(i=0; i < map->maxsize; i++) { + keys_to_array(map->data[i], res, &j); + } + + if (sort) + res = sort_key_vector(res, *size); + + return res; +} + +int +hashmap_key_is_in_vector(const char** vec, size_t size, const char* key) +{ + size_t i; + for (i = 0; i < size; i++) { + if (strcmp(vec[i], key) == 0) /* found */ + return 1; + } + + return 0; +} + +const char** +hashmap_get_update_key_vector(const char** vec1, size_t vec1_size, + const char** vec2, size_t vec2_size, size_t* res_size) +{ + const char** res; + size_t i, j; + + *res_size = vec2_size; + + res = (const char**) malloc(*res_size * sizeof(char*)); + if (res == NULL) + return NULL; + + /* get all keys from vec2 which are not set in vec1 */ + j = 0; + for (i = 0; i < vec2_size; i++) { + if (!hashmap_key_is_in_vector(vec1, vec1_size, vec2[i])) + res[j++] = vec2[i]; + } + + *res_size = j; + return res; +} |