4coder/4tech_table.cpp

263 lines
6.2 KiB
C++

/*
* Mr. 4th Dimention - Allen Webster
*
* 14.02.2016
*
* 4tech C style genereic hash table
*
*/
// TOP
#define TableHashEmpty 0
#define TableHashDeleted 1
#define TableHashMin 0x10000000
typedef u32 Hash_Function(void *item, void *arg);
typedef i32 Compare_Function(void *key, void *item, void *arg);
struct Table{
u32 *hash_array;
u8 *data_array;
i32 count, max;
i32 item_size;
};
internal i32
table_required_mem_size(i32 table_size, i32 item_size){
i32 mem_size, hash_size;
hash_size = ((table_size * sizeof(u32)) + 7) & ~7;
mem_size = hash_size + table_size * item_size;
return(mem_size);
}
internal void
table_init_memory(Table *table, void *memory, i32 table_size, i32 item_size){
i32 hash_size = table_size * sizeof(u32);
hash_size = (hash_size + 7) & ~7;
table->hash_array = (u32*)memory;
table->data_array = (u8*)(table->hash_array) + hash_size;
table->count = 0;
table->max = table_size;
table->item_size = item_size;
}
internal b32
table_at_capacity(Table *table){
b32 result = 1;
if (table->count * 8 < table->max * 7){
result = 0;
}
return(result);
}
internal b32
table_add(Table *table, void *item, void *arg, Hash_Function *hash_func, Compare_Function *comp_func){
u32 hash, *inspect;
i32 i, start;
Assert(table->count * 8 < table->max * 7);
hash = (hash_func(item, arg) | TableHashMin);
i = hash % table->max;
start = i;
inspect = table->hash_array + i;
while (*inspect >= TableHashMin){
if (*inspect == hash){
if (comp_func(item, table->data_array + i*table->item_size, arg) == 0){
return(1);
}
}
++i;
++inspect;
if (i == table->max){
i = 0;
inspect = table->hash_array;
}
Assert(i != start);
}
*inspect = hash;
memcpy(table->data_array + i*table->item_size, item, table->item_size);
++table->count;
return(0);
}
internal b32
table_find_pos(Table *table, void *search_key, void *arg, i32 *pos, i32 *index, Hash_Function *hash_func, Compare_Function *comp_func){
u32 hash, *inspect;
i32 i, start;
Assert((table->count - 1) * 8 < table->max * 7);
hash = (hash_func(search_key, arg) | TableHashMin);
i = hash % table->max;
start = i;
inspect = table->hash_array + i;
while (*inspect != TableHashEmpty){
if (*inspect == hash){
if (comp_func(search_key, table->data_array + i*table->item_size, arg) == 0){
if (pos) *pos = i*table->item_size;
if (index) *index = i;
return(1);
}
}
++i;
++inspect;
if (i == table->max){
i = 0;
inspect = table->hash_array;
}
if (i == start) break;
}
return(0);
}
inline void*
table_find_item(Table *table, void *search_key, void *arg, Hash_Function *hash_func, Compare_Function *comp_func){
i32 pos;
void *result = 0;
if (table_find_pos(table, search_key, arg, &pos, 0, hash_func, comp_func)){
result = table->data_array + pos;
}
return(result);
}
inline void
table_remove_index(Table *table, i32 index){
table->hash_array[index] = TableHashDeleted;
--table->count;
}
inline b32
table_remove_match(Table *table, void *search_key, void *arg, Hash_Function *hash_func, Compare_Function *comp_func){
i32 index;
b32 result = 0;
if (table_find_pos(table, search_key, arg, 0, &index, hash_func, comp_func)){
table_remove_index(table, index);
result = 1;
}
return(result);
}
inline void
table_clear(Table *table){
table->count = 0;
memset(table->hash_array, 0, table->max*sizeof(*table->hash_array));
}
internal void
table_rehash(Table *src, Table *dst, void *arg, Hash_Function *hash_func, Compare_Function *comp_func){
i32 i, c, count, item_size;
u32 *hash_item;
u8 *data_item;
Assert((dst->count + src->count - 1) * 7 < dst->max * 8);
Assert(dst->item_size == src->item_size);
count = src->count;
hash_item = src->hash_array;
data_item = src->data_array;
item_size = src->item_size;
for (i = 0, c = 0; c < count; ++i, ++hash_item, data_item += item_size){
if (*hash_item >= TableHashMin){
++c;
table_add(dst, data_item, arg, hash_func, comp_func);
}
}
}
internal u32
tbl_string_hash(void *item, void *arg){
String *string = (String*)item;
char *str;
i32 i,len;
u32 x = 5381;
char c;
(void)arg;
str = string->str;
len = string->size;
i = 0;
while (i < len){
c = str[i++];
x = ((x << 5) + x) + c;
}
return(x);
}
internal i32
tbl_string_compare(void *a, void *b, void *arg){
String *stra = (String*)a;
String *strb = (String*)b;
i32 result = !match(*stra, *strb);
return(result);
}
internal u32
tbl_offset_string_hash(void *item, void *arg){
Offset_String *string = (Offset_String*)item;
char *str;
i32 i,len;
u32 x = 5381;
char c;
str = ((char*)arg) + string->offset;
len = string->size;
i = 0;
while (i < len){
c = str[i++];
x = ((x << 5) + x) + c;
}
return(x);
}
internal i32
tbl_offset_string_compare(void *a, void *b, void *arg){
Offset_String *ostra = (Offset_String*)a;
Offset_String *ostrb = (Offset_String*)b;
String stra = make_string((char*)arg + ostra->offset, ostra->size);
String strb = make_string((char*)arg + ostrb->offset, ostrb->size);
i32 result = !match(stra, strb);
return(result);
}
struct String_Space{
char *space;
i32 pos, new_pos, max;
};
internal Offset_String
strspace_append(String_Space *space, char *str, i32 len){
Offset_String result = {};
if (space->new_pos + len <= space->max){
result.offset = space->new_pos;
result.size = len;
memcpy(space->space + space->new_pos, str, len);
space->new_pos = space->pos + len;
}
return(result);
}
internal void
strspace_keep_prev(String_Space *space){
space->pos = space->new_pos;
}
internal void
strspace_discard_prev(String_Space *space){
space->new_pos = space->pos;
}
// BOTTOM