Quote: "How's your magnet, Comet?"
Doing pretty good I think, haven't got superpowers yet though. See other thread for pictures.
Also make more response videos, the last one was fun to watch.
@all
Dropped back to pure C programming and implemented a contiguous memory container, which was fun:
vector.h
#define DATA_POINTER_TYPE unsigned char*
typedef struct vector_t
{
const int element_size;
int count; /* number of elements inserted */
int size; /* how many elements actually fit into the allocated space */
DATA_POINTER_TYPE data;
} vector_t;
vector_t* vector_create(const int element_size);
void vector_destroy(vector_t* vector);
void vector_clear(vector_t* vector);
#define vector_count(x) ((x)->count)
void vector_push(vector_t* vector, void* data);
void* vector_pop(vector_t* vector);
void vector_insert(vector_t* vector, int index, void* data);
void vector_erase(vector_t* vector, int index);
void* vector_get_element(vector_t*, int index);
static void vector_expand(vector_t* vector, int insertion_index);#include <string.h>
#include <stdlib.h>
#include <vector.h>
vector_t* vector_create(const int element_size)
{
vector_t* vector = malloc(sizeof(vector_t));
vector_t tmp = {element_size, 0, 0, NULL};
memcpy(vector, &tmp, sizeof(vector_t));
return vector;
}
void vector_destroy(vector_t* vector)
{
vector_clear(vector);
free(vector);
}
void vector_clear(vector_t* vector)
{
if(vector->data)
free(vector->data);
vector->count = 0;
}
void vector_push(vector_t* vector, void* data)
{
if(vector->count == vector->size)
vector_expand(vector, -1);
/* copy new element into end of vector */
int offset = vector->element_size * vector->count;
memcpy(vector->data + offset, data, vector->element_size);
++vector->count;
}
void* vector_pop(vector_t* vector)
{
if(!vector->count)
return NULL;
--vector->count;
return vector->data + (vector->element_size * vector->count);
}
void vector_insert(vector_t* vector, int index, void* data)
{
/* last index (which would normally be invalid) is valid in this case */
if(index > vector->size)
return;
if(vector->count == vector->size)
vector_expand(vector, index);
/* copy new element into the specified index */
int offset = vector->element_size * index;
memcpy(vector->data + offset, data, vector->element_size);
++vector->count;
}
void vector_erase(vector_t* vector, int index)
{
if(index >= vector->size)
return;
/* shift memory right after the specified element down by one element */
int offset = vector->element_size * index;
int total_size = vector->element_size * vector->count;
memcpy(vector->data + offset, vector->data + offset + vector->element_size, total_size - offset);
--vector->count;
}
void* vector_get_element(vector_t* vector, int index)
{
if(index >= vector->count)
return NULL;
return vector->data + (vector->element_size * index);
}
static void vector_expand(vector_t* vector, int insertion_index)
{
/* expand by factor 2 */
int new_size = vector->size << 2;
if(new_size == 0)
new_size = 2;
/* prepare for reallocating data */
DATA_POINTER_TYPE old_data = vector->data;
DATA_POINTER_TYPE new_data = malloc(vector->element_size * new_size);
/* if no insertion index is required, copy all data to new memory */
if(insertion_index == -1 || insertion_index >= new_size)
memcpy(new_data, old_data, vector->element_size * vector->count);
/* keep space for one element at the insertion index */
else
{
/* copy old data up until right before insertion offset */
int offset = vector->element_size * insertion_index;
int total_size = vector->element_size * vector->count;
memcpy(new_data, old_data, offset);
/* copy the rest of the old data into the memory right after insertion offset */
memcpy(new_data + offset + vector->element_size, old_data + offset, total_size - offset);
}
vector->data = new_data;
free(old_data);
/* update counters */
vector->size = new_size;
}/* create vector container to hold integers */
vector_t* container = vector_create(sizeof(int));
/* insert some values */
int a=6, b=3, c=7;
vector_push(container, &a);
vector_push(container, &b);
vector_push(container, &c);
/* print second value in vector */
printf("%d\n", *((int*) vector_get_element(container, 1));
/* erase second element */
vector_erase_element(container, 1);
/* destroy container */
vector_destroy(container);I like offending people. People who get offended should be offended. --
Linus Torvalds
