push.c

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/* ************************************************************************** */
/*      ____    _    _____ ____     _    _   _   _____ _  _   ____  ____      */
/*     / ___|  / \  |  ___|  _ \   / \  | \ | | |_   _| || | |  _ \/ ___|     */
/*     \___ \ / _ \ | |_  | |_) | / _ \ |  \| |   | | | || |_| | | \___ \     */
/*      ___) / ___ \|  _| |  _ < / ___ \| |\  |   | | |__   _| |_| |___) |    */
/*     |____/_/   \_|_|   |_| \_/_/   \_|_| \_|   |_|    |_| |____/|____/     */
/*                                                                            */
/* ************************************************************************** */
 
#include "private.h"
 
#include "o2s/deque.h"
#include "o2s/preprocessing.h" // min
 
#include <iso646.h>            // not
#include <string.h>            // memcpy

bool deque_push_front(deque_t* self, const void* element)
{
    if (deque_is_full(self))
        return false;
    self->front = deque_pointer_before(self, self->front);
    memcpy(self->front, element, deque_offset(self, 1));
    self->count += 1;
    return true;
}

bool deque_push_front_n(deque_t* self, const void* elements, size_t count)
{
    if (count > deque_room(self))
        return false;
    while (count-- > 0)
    {
        deque_push_front(self, elements);
        elements += deque_offset(self, 1);
    }
    return true;
}

bool deque_push_back(deque_t* self, const void* element)
{
    return deque_push_back_n(self, element, 1);
}

bool deque_push_back_n(deque_t* self, const void* elements, size_t count)
{
    size_t first_pass;
    size_t first_pass_size;
 
    if (count > deque_room(self))
        return false;
    first_pass = min(count, deque_distance(self, self->back, deque_end(self)));
    first_pass_size = deque_offset(self, first_pass);
    memcpy(self->back, elements, first_pass_size);
    self->back += first_pass_size;
    self->count += first_pass;
    if (first_pass < count)
    {
        self->back = deque_begin(self);
        deque_push_back_n(self, elements + first_pass_size, count - first_pass);
    }
    return true;
}