1 files changed, 76 insertions, 0 deletions
diff --git a/nerv/common.c b/nerv/common.c
new file mode 100644
index 0000000..b4e39e6
--- /dev/null
+++ b/nerv/common.c
@@ -0,0 +1,76 @@
+#include "common.h"
+#include <stdarg.h>
+int nerv_error(lua_State *L, const char *err_mesg_fmt, ...) {
+    va_list ap;
+    va_start(ap, err_mesg_fmt);
+    lua_pushstring(L, "[nerv] internal error: ");
+    lua_pushvfstring(L, err_mesg_fmt, ap); 
+    lua_concat(L, 2);
+    lua_error(L);
+    va_end(ap);
+    return 0;
+}
+
+int nerv_error_method_not_implemented(lua_State *L) {
+    return nerv_error(L, "method not implemented"); 
+}
+
+void luaN_append_methods(lua_State *L, const luaL_Reg *mlist) {
+    for (; mlist->func; mlist++)
+    {
+        lua_pushcfunction(L, mlist->func);
+        lua_setfield(L, -2, mlist->name);
+    }
+}
+
+HashMap *hashmap_create(size_t size, HashKey_t hfunc, HashMapCmp_t cmp) {
+    HashMap *res = (HashMap *)malloc(sizeof(HashMap));
+    res->bucket = calloc(size, sizeof(HashNode));
+    res->cmp = cmp;
+    res->hfunc = hfunc;
+    res->size = size;
+    return res;
+}
+
+void *hashmap_getval(HashMap *h, const char *key) {
+    size_t idx = h->hfunc(key) % h->size;
+    HashNode *ptr;
+    for (ptr = h->bucket[idx]; ptr; ptr = ptr->next)
+    {
+        if (!h->cmp(ptr->key, key))
+            return ptr->val;
+    }
+    return NULL;
+}
+
+void hashmap_setval(HashMap *h, const char *key, void *val) {
+    size_t idx = h->hfunc(key) % h->size;
+    HashNode *ptr = malloc(sizeof(HashNode));
+    ptr->next = h->bucket[idx];
+    h->bucket[idx] = ptr;
+    ptr->key = key;
+    ptr->val = val;
+}
+
+void hashmap_clear(HashMap *h) {
+    size_t i;
+    for (i = 0; i < h->size; i++)
+    {
+        HashNode *ptr, *nptr;
+        for (ptr = h->bucket[i]; ptr; ptr = nptr)
+        {
+            nptr = ptr->next;
+            free(ptr->val);
+            free(ptr);
+        }
+        h->bucket[i] = NULL;
+    }
+}
+
+size_t bkdr_hash(const char *key) {
+    unsigned int seed = 131;
+    unsigned int res = 0;
+    while (*key)
+        res = res * seed + *key++;
+    return res;
+}