HashMap C library

This library provide type-customizable linked list HashMap and functions to made their use easy. Working on any operating system.

How to install

Just drop async.h and async.c in your project and include async.h using a relative path.

Usage

hmap_init()

HashMap
hmap_init();

Initialize a HashMap. It's very important to use this function before sending a HashMap variable into any functions of this library! If not it will just crash your program.

hmap_set()

hval
hmap_get(HashMap map, hkey key);

Get the value paired with the given key.

Parameters

map: a HashMap.
key: the wanted value's key.

Return value

It returns a hval, defined by HMAP_VAL_TYPE (see Change default types part) or NULL if the key doesn't exists.

hmap_contains()

int
hmap_contains(HashMap map, hkey key);

Check if a key is contained in the map.

Parameters

map: a HashMap.
key: the wanted key.

Return value

1 if it's contained in map, 0 if not.

hmap_set()

void
hmap_set(HashMap *map, hkey key, hval val);

Set a key-value pair on a map.
A new Hash will be created in case of the key is not already present, if the key already exists, the value will be replaced.

Parameters

map: a HashMap.
key: the key.
val: the value.

hmap_remove()

int
hmap_remove(HashMap *map, hkey key);

Remove a key-value from a map.

Parameters

map: a HashMap.
key: the key to remove.

Return value

An error code, if it occurs. This code can be 0 if no error or HMAP_KEY_NOT_EXISTS if the key to remove doesn't exists.

Parameters

map: a HashMap.
key: the key.
val: the value.

hmap_loop()

void
hmap_loop(HashMap *map, void (*cb)(Hash*, void*), void* args);

Call a function (cb) for each Hash in a HashTable.

Parameters

map: a HashMap.
cb: a pointer to a function that takes a Hash * and a void *.
args: the callback's arguments. It will be sent to the second callback's argument.

Change default types

Their is 2 constants defined in hmap.h:

• HMAP_KEY_TYPE (hkey)
• HMAP_VAL_TYPE (hval)

By default HMAP_KEY_TYPE is a char * and HMAP_VAL_TYPE is a void *.
To customize them, just define them before including hmap.h.

#define HMAP_KEY_TYPE char *
#define HMAP_VAL_TYPE void *

#include "hmap.h"