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-rw-r--r--map.c77
1 files changed, 77 insertions, 0 deletions
diff --git a/map.c b/map.c
new file mode 100644
index 0000000..58ed548
--- /dev/null
+++ b/map.c
@@ -0,0 +1,77 @@
+#include "include/map.h"
+#include <stdlib.h>
+#include <stdio.h>
+string_map init_map(uint32_t size){
+ string_map tmp;
+
+ tmp.size = size;
+ tmp.head = (node **)malloc(sizeof(node *) * size);
+
+ node **h = tmp.head;
+ for(int i = 0; i < size; ++i){
+ h[i] = NULL;
+ }
+
+ return tmp;
+}
+
+/*
+ * 64-bit FNV-1 hash
+ * https://en.wikipedia.org/wiki/Fowler%E2%80%93Noll%E2%80%93Vo_hash_function
+ */
+uint32_t hash_function(char *key, uint32_t size){
+ uint64_t hash = FNV_offset_basis;
+ uint32_t key_size = strlen(key);
+
+ for(int i = 0; i < key_size; ++i){
+ hash *= FNV_prime;
+ hash ^= (uint64_t)key[i];
+ }
+
+ return hash % size;
+}
+
+node *create_node(char *key, char *value){
+ node *tmp = (node *)malloc(sizeof(node));
+ tmp->key = key;
+ tmp->value = value;
+ tmp->next = NULL;
+ return tmp;
+}
+
+void insert_map(char *key, char *value, string_map map){
+ uint32_t hash_offset = hash_function(key, map.size);
+
+ if(*(map.head + hash_offset) == NULL){
+ node *tmp = create_node(key, value);
+ *(map.head + hash_offset) = tmp;
+ return;
+ }
+
+ node *head = *(map.head + hash_offset);
+ while(head->next != NULL){
+ if(strcmp(key, (head->key)) == 0){
+ printf("REPETIDO\n");
+ return;
+ }
+ head = head->next;
+ }
+
+ node *tmp = create_node(key, value);
+ (head->next) = tmp;
+}
+
+char *get_value(char *key, string_map map){
+ uint32_t hash_offset = hash_function(key, map.size);
+ node *head = *(map.head + hash_offset);
+
+ while(head != NULL){
+ if(strcmp(key, (head->key)) == 0){
+ return head->value;
+ }
+ head = head->next;
+ }
+
+ fprintf(stderr, "VALOR NAO ESTA NO HASH TABLE\n");
+ return NULL;
+}