C hash lib inspired by Lua's Table

APIS

Create

  struct ltable*  ltable_create(size_t vmemsz, unsigned int seed);

create a table instance.

seed is used to gen hash value, LTABLE_SEED is used when 0 supplied.

vmemsz is the maximum memory size a single table value can occupy. If you have multiple types of table value, I recommend you to use a tag union to group them, for example:

struct TLValue {
    int type;
    union {
        double f;
        char * s[128];
        void *p;
    } u;
};

struct ltable* t = ltable_create(sizeof(struct TLValue), 0);

Key

4 types of key are supported

LTABLE_KEYNUM      1
LTABLE_KEYINT      2
LTABLE_KEYSTR      3
LTABLE_KEYOBJ      4

Use corresponding function to create them, like ltable_intkey to gen int-type key, ltable_numkey for double-type key, e.t.c.

Get, Set and Del

void* ltable_get(struct ltable* t, const struct ltable_key* key);
void* ltable_set(struct ltable* t, const struct ltable_key* key);
void  ltable_del(struct ltable* t, const struct ltable_key* key);

ltable_get will return the addr of value if it finds any, otherwise NULL returned.

ltable_set returns the same with ltable_get when the key is found, but it will create a new one otherwise.

Iter

use ltable_next to iter among table.

void* ltable_next(struct ltable *t, unsigned int *ip, struct ltable_key *key);

returns the value addr, or NULL when no more item to be iterated.

ip is the iter handle, which must initialize to 0 at beginning of iteration.

key will be filled with corresponding key. set it to NULL if you don't need it.

Array

ltable's array is 0-based, which is different from Lua's 1-based array. For your convenience, ltable offered an auxiliary function to fetch array item, insead of ltable_get:

  void* ltable_getn(struct ltable* t, int i);

To iter on array is easy:

int i = 0;
while (p = ltable_getn(t, i++)) {...}

EXAMPLES

see test.c

zhaozg / lua-shared