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Vector

Vector is a resizeable C array.

Vector expects a frequent resizes hence it keeps the underlying memory size slightly bigger than actual size in order to keep the memory reallocations at minimum.

Vector allocation
void *gp_vec_new(size_t length, size_t unit);

/* Example usage */
struct user_struct {
        ...
};

void func(...)
{
        struct user_struct *array = gp_vec_new(10, sizeof(struct user_struct));

        if (!array)
                return;

        array[0].foo = 123;

        ...

        gp_vec_free(array);
}

Allocates a new vector of initial length and for elements of size unit.

Initial length can be 0 as vector can be resized later.

Returns NULL on allocation failure.

Vector free
void gp_vec_free(void *self);

Frees the vector. Passing NULL as self is no-op.

Vector lenght and unit
size_t gp_vec_len(const void *self);

size_t gp_vec_unit(const void *self);

The gp_vec_len() returns vector length i.e. number of elements in the vector.

The gp_vec_size() returns vector element size i.e. number of bytes each vector element occupies.

Vector resize
void *gp_vec_resize(void *self, size_t length);

void *gp_vec_append(void *self, size_t lenght);

/* Example usage */
int *func(int *array, int append)
{
        size_t last = gp_vec_len(array);

        int *new = gp_vec_append(self, 1);
        if (!new)
                return NULL;

        new[last] = append;

        return new;
}

Resizes a vector.

If space was added after the vector it’s filled with zeroes.

The call may return NULL if we attempted to add space to the vector and allocation has failed, in this case the original vector is kept untouched.

Vector shrinking cannot fail.

Warning Returns a new pointer to the vector!
Vector insert
void *gp_vec_ins(void *self, size_t off, size_t length);

/* Example usage */
int *func(int *array, int prepend)
{
        int *new = gp_vec_ins(self, 0, 1);
        if (!new)
                return NULL;

        new[0] = prepend;

        return new;
}

Inserts a gap into the vector, the newly inserted gap is filled with zeroes.

The call may return NULL if underlying memory allocation has failed, in this case the original vector is kept untouched.

Returns NULL if off is outside of the vector.

Warning Returns a new pointer to the vector!
Vector delete
void *gp_vec_del(void *self, size_t off, size_t length);

/* Example usage */
int *func(int *array, int *pop)
{
        int *new;

        *pop = array[0];

        new = gp_vec_del(self, 0, 1);
        if (!new)
                return NULL;

        return new;
}

Removes a range from the vector.

Returns NULL if the block is outside of the vector.

Warning Returns a new pointer to the vector!