add generic hashmap and memory usage fix

.clang-format

@@ -1,5 +1,5 @@
 BasedOnStyle: Google
-ColumnLimit: 120
+ColumnLimit: 160
 UseTab: Always
 IndentWidth: 4
 TabWidth: 4

include/server/server.h

@@ -80,17 +80,17 @@ int cws_server_accept_client(int sockfd, struct sockaddr_storage *their_sa, sock
 /**
  * @brief Closes all the file descriptors opened
  *
- * @param[in] bucket The hash map
+ * @param[in] hashmap Clients hash map
  */
-void cws_server_close_all_fds(cws_bucket *bucket);
+void cws_server_close_all_fds(cws_hashmap *hashmap);
 
 /**
  * @brief Disconnect a client
  *
  * @param[in] epfd Epoll file descriptor
  * @param[in] client_fd Client file descriptor
- * @param[in] bucket Clients hash map
+ * @param[in] hashmap Clients hash map
  */
-void cws_server_close_client(int epfd, int client_fd, cws_bucket *bucket);
+void cws_server_close_client(int epfd, int client_fd, cws_hashmap *hashmap);
 
 #endif

include/utils/hashmap.h

@@ -2,87 +2,101 @@
 #define CWS_HASHMAP_H
 
 #include <stdbool.h>
-#include <sys/socket.h>
 
-/* Each process on Linux can have a maximum of 1024 open file descriptors */
-#define CWS_HASHMAP_MAX_CLIENTS 1024
+#define CWS_HASHMAP_SIZE 1024 /**< Number of buckets in the hash map */
 
 /**
- * @brief Client Hashmap struct
- *
+ * @brief A single bucket in the hash map.
  */
 typedef struct cws_bucket_t {
-	int sockfd;					 /**< Client socket descriptor */
-	struct sockaddr_storage sas; /**< Associated socket address */
-	struct cws_bucket_t *next;	 /**< Next node in case of collision */
-	struct cws_bucket_t *prev;	 /**< Previous node in case of collision */
+	void *key;				   /**< Pointer to the key */
+	void *value;			   /**< Pointer to the value */
+	struct cws_bucket_t *next; /**< Pointer to the next bucket in case of collision */
 } cws_bucket;
 
 /**
- * @brief Calculates the hash code of a given file descriptor
+ * @brief Function pointer type for a hash function
  *
- * @param[in] sockfd The file descriptor
- * @return Returns the hash code
+ * @param[in] key Pointer to the key to hash
+ * @return The computed hash as an integer
  */
-int cws_hm_hash(int sockfd);
+typedef int cws_hash_fn(void *key);
 
 /**
- * @brief Initializes the hash map
+ * @brief Function pointer type for a key comparison function
  *
- * @param[out] bucket The hash map uninitialized
+ * @param[in] key_a Pointer to the first key
+ * @param[in] key_b Pointer to the second key
+ * @return true if the keys are considered equal, false otherwise
  */
-void cws_hm_init(cws_bucket *bucket);
+typedef bool cws_equal_fn(void *key_a, void *key_b);
 
 /**
- * @brief Inserts a key in the hash map
+ * @brief Function pointer type for freeing a key
  *
- * @param[out] bucket The hash map
- * @param[in] sockfd The file descriptor (value)
- * @param[in] sas The sockaddr (value)
+ * @param[in] key Pointer to the key to free
  */
-void cws_hm_push(cws_bucket *bucket, int sockfd, struct sockaddr_storage *sas);
+typedef void cws_free_key_fn(void *key);
 
 /**
- * @brief Removes a key from the hash map
+ * @brief Function pointer type for freeing a value
  *
- * @param[out] bucket The hash map
- * @param[in] sockfd The key
+ * @param[in] value Pointer to the value to free
  */
-void cws_hm_remove(cws_bucket *bucket, int sockfd);
+typedef void cws_free_value_fn(void *value);
 
 /**
- * @brief Searches for a key in the hash map
- *
- * @param[in] bucket The hash map
- * @param[in] sockfd The file descriptor (key)
- * @return Returns NULL or the key pointer
+ * @brief Main structure representing the hash map
  */
-cws_bucket *cws_hm_lookup(cws_bucket *bucket, int sockfd);
+typedef struct cws_hashmap_t {
+	cws_hash_fn *hash_fn;			  /**< Hash function */
+	cws_equal_fn *equal_fn;			  /**< Equality comparison function */
+	cws_free_key_fn *free_key_fn;	  /**< Key deallocation function */
+	cws_free_value_fn *free_value_fn; /**< Value deallocation function */
+
+	cws_bucket map[CWS_HASHMAP_SIZE]; /**< Array of bucket chains */
+} cws_hashmap;
 
 /**
- * @brief Cleans the hash map
+ * @brief Initializes a new hash map with user-defined behavior
  *
- * @param[out] bucket The hash map
+ * @param[in] hash_fn Function used to hash keys
+ * @param[in] equal_fn Function used to compare keys
+ * @param[in] free_key_fn Function used to free keys
+ * @param[in] free_value_fn Function used to free values
+ * @return A pointer to the newly initialized hash map
  */
-void cws_hm_free(cws_bucket *bucket);
+cws_hashmap *cws_hm_init(cws_hash_fn *hash_fn, cws_equal_fn *equal_fn, cws_free_key_fn *free_key_fn, cws_free_value_fn *free_value_fn);
 
 /**
- * @brief Checks if a file descriptor is in the bucket array (not linked list)
+ * @brief Frees all resources used by the hash map
  *
- * @param[in] bucket
- * @param[in] sockfd
- * @return true If the file descriptor is in the bucket array
- * @return false If the file descriptor is not in the bucket array (check with hm_lookup())
+ * @param[in] hashmap Pointer to the hash map to free
  */
-bool cws_hm_is_in_bucket_array(cws_bucket *bucket, int sockfd);
+void cws_hm_free(cws_hashmap *hashmap);
 
 /**
- * @brief This function will add a key even if it exists (use hm_push() instead)
+ * @brief Inserts or updates a key-value pair in the hash map
  *
- * @param bucket
- * @param sockfd
- * @param sas
+ * @param[in] hashmap Pointer to the hash map
+ * @param[in] key Pointer to the key to insert
+ * @param[in] value Pointer to the value to insert
+ * @return true if the operation succeeded, false otherwise
  */
-void cws_hm_insert(cws_bucket *bucket, int sockfd, struct sockaddr_storage *sas);
+bool cws_hm_set(cws_hashmap *hashmap, void *key, void *value);
 
-#endif
+/**
+ * @brief Retrieves a bucket by key
+ *
+ * @param[in] hashmap Pointer to the hash map
+ * @param[in] key Pointer to the key to search for
+ * @return Pointer to the found bucket, or NULL if not found
+ */
+cws_bucket *cws_hm_get(cws_hashmap *hashmap, void *key);
+
+/**
+ * TODO: Implement cws_hm_remove()
+ * @brief Removes a key-value pair from the hash map
+ */
+
+#endif

include/utils/utils.h

@@ -4,6 +4,7 @@
 #include <arpa/inet.h>
 #include <netdb.h>
 #include <netinet/in.h>
+#include <stdbool.h>
 #include <sys/socket.h>
 #include <sys/types.h>
 
@@ -23,4 +24,10 @@ void cws_utils_print_ips(const char *hostname, const char *port);
  */
 void cws_utils_get_client_ip(struct sockaddr_storage *sa, char *ip);
 
+/* TODO: add docs */
+/* Functions used for hash maps */
+int my_hash_fn(void *key);
+bool my_equal_fn(void *a, void *b);
+void my_free_value_fn(void *value);
+
 #endif

meson.build

@@ -11,3 +11,5 @@ add_global_arguments('-DUSE_COLORS', language : 'c')
 add_global_arguments('-DEVELOPER', language : 'c')
 
 executable('cws', server, include_directories : incdir, dependencies : [libyaml, libcyaml])
+
+executable('testbuild', test, include_directories : incdir)

src/http/http.c

@@ -12,6 +12,7 @@ cws_http *cws_http_parse(char *request_str, int sockfd) {
 	if (request == NULL) {
 		return NULL;
 	}
+	memset(request, 0, sizeof(cws_http));
 
 	/* Insert socket file descriptor */
 	request->sockfd = sockfd;

src/main.c

@@ -14,18 +14,18 @@ int main(int argc, char **argv) {
 
 	cws_config *config = cws_config_init();
 	if (config == NULL) {
-		CWS_LOG_ERROR("[server] Unable to read config file");
+		CWS_LOG_ERROR("Unable to read config file");
 		return 1;
 	}
 
 	struct sigaction act = {.sa_handler = cws_signal_handler};
 	ret = sigaction(SIGINT, &act, NULL);
 
-	CWS_LOG_INFO("[server] Running cws on http://%s:%s...", config->host, config->port);
+	CWS_LOG_INFO("Running cws on http://%s:%s...", config->host, config->port);
 
 	ret = cws_server_start(config->host, config->port);
 	if (ret < 0) {
-		CWS_LOG_ERROR("[server] Unable to start web server");
+		CWS_LOG_ERROR("Unable to start web server");
 	}
 
 	cws_config_free(config);

src/meson.build

@@ -1,3 +1,6 @@
 server = files('main.c', 'server/server.c')
 server += files('utils/utils.c', 'utils/hashmap.c', 'utils/config.c')
 server += files('http/http.c')
+
+test = files('../test/hashmap_test.c')
+test += files('utils/hashmap.c')

src/server/server.c

@@ -26,7 +26,7 @@ int cws_server_start(const char *hostname, const char *service) {
 
 	int status = getaddrinfo(hostname, service, &hints, &res);
 	if (status != 0) {
-		CWS_LOG_ERROR("[server] getaddrinfo() error: %s", gai_strerror(status));
+		CWS_LOG_ERROR("getaddrinfo() error: %s", gai_strerror(status));
 		exit(EXIT_FAILURE);
 	}
 
@@ -35,19 +35,19 @@ int cws_server_start(const char *hostname, const char *service) {
 	const int opt = 1;
 	status = setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR, &opt, sizeof opt);
 	if (status != 0) {
-		CWS_LOG_ERROR("[server] setsockopt(): %s", strerror(errno));
+		CWS_LOG_ERROR("setsockopt(): %s", strerror(errno));
 		exit(EXIT_FAILURE);
 	}
 
 	status = bind(sockfd, res->ai_addr, res->ai_addrlen);
 	if (status != 0) {
-		CWS_LOG_ERROR("[server] bind(): %s", strerror(errno));
+		CWS_LOG_ERROR("bind(): %s", strerror(errno));
 		exit(EXIT_FAILURE);
 	}
 
 	status = listen(sockfd, CWS_SERVER_BACKLOG);
 	if (status != 0) {
-		CWS_LOG_ERROR("[server] listen(): %s", gai_strerror(status));
+		CWS_LOG_ERROR("listen(): %s", gai_strerror(status));
 		exit(EXIT_FAILURE);
 	}
 
@@ -78,8 +78,7 @@ void cws_server_loop(int sockfd) {
 	struct sockaddr_storage their_sa;
 	socklen_t theirsa_size = sizeof their_sa;
 
-	cws_bucket clients[CWS_HASHMAP_MAX_CLIENTS];
-	cws_hm_init(clients);
+	cws_hashmap *clients = cws_hm_init(my_hash_fn, my_equal_fn, NULL, NULL);
 
 	int epfd = epoll_create1(0);
 	cws_fd_set_nonblocking(sockfd);
@@ -97,24 +96,27 @@ void cws_server_loop(int sockfd) {
 				char ip[INET_ADDRSTRLEN];
 				client_fd = cws_server_accept_client(sockfd, &their_sa, &theirsa_size);
 				cws_utils_get_client_ip(&their_sa, ip);
-				CWS_LOG_INFO("[server] Client (%s) connected", ip);
+				CWS_LOG_INFO("Client (%s) connected", ip);
 
 				cws_fd_set_nonblocking(client_fd);
 				cws_epoll_add(epfd, client_fd, EPOLLIN);
-				cws_hm_push(clients, client_fd, &their_sa);
+				cws_hm_set(clients, &client_fd, &their_sa);
 			} else {
 				char data[4096] = {0};
+				char ip[INET_ADDRSTRLEN] = {0};
 
 				/* Incoming data */
 				client_fd = revents[i].data.fd;
 				const ssize_t bytes_read = recv(client_fd, data, sizeof data, 0);
-				char ip[INET_ADDRSTRLEN];
-				cws_bucket *client = cws_hm_lookup(clients, client_fd);
-				cws_utils_get_client_ip(&client->sas, ip);
+
+				/* Retrieve client ip */
+				cws_bucket *client = cws_hm_get(clients, &client_fd);
+				struct sockaddr_storage client_sas = *(struct sockaddr_storage *)client->value;
+				cws_utils_get_client_ip(&client_sas, ip);
 
 				if (bytes_read == 0) {
 					/* Client disconnected */
-					CWS_LOG_INFO("[server] Client (%s) disconnected", ip);
+					CWS_LOG_INFO("Client (%s) disconnected", ip);
 					cws_server_close_client(epfd, client_fd, clients);
 					continue;
 				}
@@ -139,7 +141,7 @@ void cws_server_loop(int sockfd) {
 				}
 
 				cws_http_send_response(request);
-				CWS_LOG_INFO("[server] Client (%s) disconnected", ip);
+				CWS_LOG_INFO("Client (%s) disconnected", ip);
 				cws_server_close_client(epfd, client_fd, clients);
 				cws_http_free(request);
 
@@ -154,7 +156,7 @@ void cws_server_loop(int sockfd) {
 	close(epfd);
 	cws_server_close_all_fds(clients);
 	cws_hm_free(clients);
-	CWS_LOG_INFO("[server] Closing...");
+	CWS_LOG_INFO("Closing...");
 }
 
 void cws_epoll_add(int epfd, int sockfd, uint32_t events) {
@@ -164,7 +166,7 @@ void cws_epoll_add(int epfd, int sockfd, uint32_t events) {
 	const int status = epoll_ctl(epfd, EPOLL_CTL_ADD, sockfd, &event);
 
 	if (status != 0) {
-		CWS_LOG_ERROR("[server] epoll_ctl_add(): %s", strerror(errno));
+		CWS_LOG_ERROR("epoll_ctl_add(): %s", strerror(errno));
 		exit(EXIT_FAILURE);
 	}
 }
@@ -173,7 +175,7 @@ void cws_epoll_del(int epfd, int sockfd) {
 	const int status = epoll_ctl(epfd, EPOLL_CTL_DEL, sockfd, NULL);
 
 	if (status != 0) {
-		CWS_LOG_ERROR("[server] epoll_ctl_del(): %s", strerror(errno));
+		CWS_LOG_ERROR("epoll_ctl_del(): %s", strerror(errno));
 		exit(EXIT_FAILURE);
 	}
 }
@@ -182,7 +184,7 @@ void cws_fd_set_nonblocking(int sockfd) {
 	const int status = fcntl(sockfd, F_SETFL, O_NONBLOCK);
 
 	if (status == -1) {
-		CWS_LOG_ERROR("[server] fcntl(): %s", gai_strerror(status));
+		CWS_LOG_ERROR("fcntl(): %s", gai_strerror(status));
 		exit(EXIT_FAILURE);
 	}
 }
@@ -192,7 +194,7 @@ int cws_server_accept_client(int sockfd, struct sockaddr_storage *their_sa, sock
 
 	if (client_fd == -1) {
 		if (errno != EWOULDBLOCK) {
-			CWS_LOG_ERROR("[server] accept(): %s", strerror(errno));
+			CWS_LOG_ERROR("accept(): %s", strerror(errno));
 		}
 		return -1;
 	}
@@ -200,11 +202,12 @@ int cws_server_accept_client(int sockfd, struct sockaddr_storage *their_sa, sock
 	return client_fd;
 }
 
-void cws_server_close_all_fds(cws_bucket *bucket) {
-	for (size_t i = 0; i < CWS_HASHMAP_MAX_CLIENTS; ++i) {
+void cws_server_close_all_fds(cws_hashmap *hashmap) {
+	/* TODO: fix this */
+
+	/*for (size_t i = 0; i < CWS_HASHMAP_SIZE; ++i) {
 		close(bucket[i].sockfd);
 		if (bucket[i].next != NULL) {
-			/* Close the fds */
 			cws_bucket *p = bucket[i].next;
 			cws_bucket *next = p->next;
 			do {
@@ -213,11 +216,11 @@ void cws_server_close_all_fds(cws_bucket *bucket) {
 				next = p != NULL ? p->next : NULL;
 			} while (p != NULL);
 		}
-	}
+	}*/
 }
 
-void cws_server_close_client(int epfd, int client_fd, cws_bucket *clients) {
+void cws_server_close_client(int epfd, int client_fd, cws_hashmap *hashmap) {
 	cws_epoll_del(epfd, client_fd);
-	cws_hm_remove(clients, client_fd);
+	/* TODO: cws_hm_remove() */
 	close(client_fd);
 }

src/utils/hashmap.c

@@ -1,101 +1,137 @@
 #include "utils/hashmap.h"
 
+#include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 
-int cws_hm_hash(int sockfd) { return sockfd % CWS_HASHMAP_MAX_CLIENTS; }
+cws_hashmap *cws_hm_init(cws_hash_fn *hash_fn, cws_equal_fn *equal_fn, cws_free_key_fn *free_key_fn, cws_free_value_fn *free_value_fn) {
+	/* Allocate hash map struct */
+	cws_hashmap *hashmap = (cws_hashmap *)malloc(sizeof(cws_hashmap));
 
-void cws_hm_init(cws_bucket *bucket) {
-	/* Initialize everything to 0 for the struct, then -1 for fd and next to NULL */
-	memset(bucket, 0, sizeof(cws_bucket) * CWS_HASHMAP_MAX_CLIENTS);
-
-	for (size_t i = 0; i < CWS_HASHMAP_MAX_CLIENTS; ++i) {
-		bucket[i].sockfd = -1;
-		bucket[i].next = NULL;
-		bucket[i].prev = NULL;
-	}
-}
-
-void cws_hm_insert(cws_bucket *bucket, int sockfd, struct sockaddr_storage *sas) {
-	int index = cws_hm_hash(sockfd);
-
-	if (bucket[index].sockfd == -1) {
-		/* Current slot is empty */
-		bucket[index].sockfd = sockfd;
-		bucket[index].sas = *sas;
-	} else {
-		/* Append the new key to the head (not the first element because it belongs to the array) of the linked
-		 * list */
-		cws_bucket *p = &bucket[index];
-		cws_bucket *new = malloc(sizeof(cws_bucket));
-		new->sockfd = sockfd;
-		new->sas = *sas;
-		new->next = p->next;
-		new->prev = p;
-		p->next = new;
-	}
-}
-
-cws_bucket *cws_hm_lookup(cws_bucket *bucket, int sockfd) {
-	int index = cws_hm_hash(sockfd);
-
-	if (bucket[index].sockfd != sockfd) {
-		cws_bucket *p;
-		for (p = bucket[index].next; p != NULL && p->sockfd != sockfd; p = p->next);
-		return p;
-	} else {
-		return &bucket[index];
+	if (hashmap == NULL) {
+		return NULL;
 	}
 
-	return NULL;
+	/* Populate hash map with given parameters */
+	hashmap->hash_fn = hash_fn;
+	hashmap->equal_fn = equal_fn;
+	hashmap->free_key_fn = free_key_fn;
+	hashmap->free_value_fn = free_value_fn;
+	/* Clear cws_bucket map */
+	memset(hashmap->map, 0, sizeof(hashmap->map));
+
+	return hashmap;
 }
 
-void cws_hm_push(cws_bucket *bucket, int sockfd, struct sockaddr_storage *sas) {
-	if (cws_hm_lookup(bucket, sockfd) == NULL) {
-		cws_hm_insert(bucket, sockfd, sas);
-	}
-}
-
-void cws_hm_remove(cws_bucket *bucket, int sockfd) {
-	if (cws_hm_is_in_bucket_array(bucket, sockfd)) {
-		/* Instead of doing this I could copy the memory of the next node into the head */
-		int index = cws_hm_hash(sockfd);
-		bucket[index].sockfd = -1;
-
+void cws_hm_free(cws_hashmap *hashmap) {
+	if (hashmap == NULL) {
 		return;
 	}
 
-	/* Key not in the bucket array, let's search in the linked list */
-	cws_bucket *p = cws_hm_lookup(bucket, sockfd);
-	if (p == NULL) return;
-	p->prev->next = p->next;
-	if (p->next != NULL) {
-		/* If there's a next node update the previous node */
-		p->next->prev = p->prev;
-	}
-	free(p);
-}
+	for (size_t i = 0; i < CWS_HASHMAP_SIZE; ++i) {
+		cws_bucket *bucket = &hashmap->map[i];
+		if (bucket->key != NULL) {
+			if (hashmap->free_key_fn != NULL) {
+				hashmap->free_key_fn(bucket->key);
+			}
+			if (hashmap->free_value_fn != NULL) {
+				hashmap->free_value_fn(bucket->value);
+			}
+		}
 
-void cws_hm_free(cws_bucket *bucket) {
-	cws_bucket *p, *next;
-
-	for (size_t i = 0; i < CWS_HASHMAP_MAX_CLIENTS; ++i) {
-		if (bucket[i].next != NULL) {
-			/* Free the malloc */
-			p = bucket[i].next;
-			next = p->next;
-			do {
-				free(p);
-				p = next;
-				next = p != NULL ? p->next : NULL;
-			} while (p != NULL);
+		bucket = bucket->next;
+		while (bucket) {
+			if (hashmap->free_key_fn != NULL) {
+				hashmap->free_key_fn(bucket->key);
+			}
+			if (hashmap->free_value_fn != NULL) {
+				hashmap->free_value_fn(bucket->value);
+			}
+			cws_bucket *next = bucket->next;
+			free(bucket);
+			bucket = next;
 		}
 	}
+
+	free(hashmap);
 }
 
-bool cws_hm_is_in_bucket_array(cws_bucket *bucket, int sockfd) {
-	int index = cws_hm_hash(sockfd);
-	if (bucket[index].sockfd == sockfd) return true;
+bool cws_hm_set(cws_hashmap *hashmap, void *key, void *value) {
+	/* Get hash index */
+	int index = hashmap->hash_fn(key);
+	cws_bucket *bucket = &hashmap->map[index];
 
-	return false;
+	/* Check if the key at index is empty */
+	if (bucket->key == NULL) {
+		/* Bucket is empty */
+		/* Set the key and value */
+		bucket->key = key;
+		bucket->value = value;
+		bucket->next = NULL;
+
+		return true;
+	}
+
+	/* Check if bucket is already set */
+	if (hashmap->equal_fn(bucket->key, key)) {
+		/* Same key, free value and update it */
+		if (hashmap->free_value_fn != NULL) {
+			hashmap->free_value_fn(bucket->value);
+		}
+		bucket->value = value;
+
+		return true;
+	}
+
+	/* Key not found, iterate through the linked list */
+	cws_bucket *next = bucket->next;
+	while (next) {
+		if (hashmap->equal_fn(next->key, key)) {
+			/* Same key, free value and update it */
+			if (hashmap->free_value_fn != NULL) {
+				hashmap->free_value_fn(next->value);
+			}
+			next->value = value;
+			return true;
+		}
+		next = next->next;
+	}
+
+	/* Append the new key/value to the head of the linked list */
+	next = (cws_bucket *)malloc(sizeof(cws_bucket));
+	if (next == NULL) {
+		return false;
+	}
+	next->key = key;
+	next->value = value;
+	next->next = bucket->next;
+	bucket->next = next;
+
+	return true;
+}
+
+cws_bucket *cws_hm_get(cws_hashmap *hashmap, void *key) {
+	/* Return if key is null */
+	if (key == NULL) {
+		return NULL;
+	}
+
+	int index = hashmap->hash_fn(key);
+	cws_bucket *bucket = &hashmap->map[index];
+
+	/* Key is not in the hash map */
+	if (bucket == NULL || bucket->key == NULL) {
+		return NULL;
+	}
+
+	/* Iterate through the linked list */
+	while (bucket) {
+		if (hashmap->equal_fn(bucket->key, key)) {
+			return bucket;
+		}
+		bucket = bucket->next;
+	}
+
+	/* Key not found */
+	return NULL;
 }

src/utils/utils.c

@@ -43,4 +43,27 @@ void cws_utils_get_client_ip(struct sockaddr_storage *sa, char *ip) {
 	struct sockaddr_in *sin = (struct sockaddr_in *)sa;
 
 	inet_ntop(AF_INET, &sin->sin_addr, ip, INET_ADDRSTRLEN);
-}
+}
+
+int my_hash_fn(void *key) {
+	char *key_str = (char *)key;
+	size_t key_len = strlen(key_str);
+
+	int total = 0;
+
+	for (size_t i = 0; i < key_len; ++i) {
+		total += (int)key_str[i];
+	}
+
+	return total % 2069;
+}
+
+bool my_equal_fn(void *a, void *b) {
+	if (strcmp((char *)a, (char *)b) == 0) {
+		return true;
+	}
+
+	return false;
+}
+
+void my_free_str_fn(void *value) { free(value); }

test/hashmap_test.c

@@ -0,0 +1,65 @@
+#include "utils/hashmap.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "utils/colors.h"
+
+int my_hash_fn(void *key) {
+	char *key_str = (char *)key;
+	size_t key_len = strlen(key_str);
+
+	int total = 0;
+
+	for (size_t i = 0; i < key_len; ++i) {
+		total += (int)key_str[i];
+	}
+
+	return total % 2069;
+}
+
+bool my_equal_fn(void *a, void *b) {
+	if (strcmp((char *)a, (char *)b) == 0) {
+		return true;
+	}
+
+	return false;
+}
+
+void my_free_fn(void *value) { free(value); }
+
+int main(void) {
+	bool ret;
+	cws_hashmap *str_hashmap = cws_hm_init(my_hash_fn, my_equal_fn, my_free_fn, my_free_fn);
+
+	char *key = strdup("test1");
+	char *value = strdup("value1");
+
+	if (key == NULL || value == NULL) {
+		CWS_LOG_ERROR("strdup()");
+
+		return 1;
+	}
+
+	ret = cws_hm_set(str_hashmap, (void *)key, (void *)value);
+	if (!ret) {
+		CWS_LOG_WARNING("Unable to set %s:%s", key, value);
+	}
+
+	cws_bucket *bucket = cws_hm_get(str_hashmap, key);
+	CWS_LOG_DEBUG("Set %s:%s", (char *)bucket->key, (char *)bucket->value);
+
+	char *another_value = strdup("another value1");
+	ret = cws_hm_set(str_hashmap, (void *)key, (void *)another_value);
+	if (!ret) {
+		CWS_LOG_WARNING("Unable to set %s:%s", key, another_value);
+	}
+
+	bucket = cws_hm_get(str_hashmap, key);
+	CWS_LOG_DEBUG("Set %s:%s", (char *)bucket->key, (char *)bucket->value);
+
+	cws_hm_free(str_hashmap);
+
+	return 0;
+}

www/index.html

@@ -14,7 +14,7 @@
 <body>
     <div>
         <h1>Hello from <span class="highlight">CWS</span>!</h1>
-        <p>Try to open an image <a href="/cws.jpg" target="_blank">here</a>.</p>
+        <p>Open an image <a href="/cws.jpg" target="_blank">here</a>.</p>
     </div>
 </body>