amxc_array_it.c

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#include <stdlib.h>
 
#include <amxc/amxc_array.h>
#include <amxc/amxc_macros.h>
 
amxc_array_it_t* amxc_array_it_get_next(const amxc_array_it_t* const reference) {
    amxc_array_it_t* it = NULL;
    amxc_array_t* array = NULL;
    size_t pos = 0;
    when_null(reference, exit);
 
    array = reference->array;
    pos = (reference - array->buffer);
    pos++;
    while(pos < array->items && !array->buffer[pos].data) {
        pos++;
    }
 
    if(pos < array->items) {
        it = &array->buffer[pos];
    }
 
exit:
    return it;
}
 
amxc_array_it_t* amxc_array_it_get_next_free(const amxc_array_it_t* const reference) {
    amxc_array_it_t* it = NULL;
    amxc_array_t* array = NULL;
    size_t pos = 0;
    when_null(reference, exit);
 
    array = reference->array;
    pos = (reference - array->buffer);
    pos++;
    while(pos < array->items && array->buffer[pos].data != NULL) {
        pos++;
    }
 
    if(pos < array->items) {
        it = &array->buffer[pos];
    }
 
exit:
    return it;
}
 
amxc_array_it_t* amxc_array_it_get_previous(const amxc_array_it_t* const reference) {
    amxc_array_it_t* it = NULL;
    amxc_array_t* array = NULL;
    size_t pos = 0;
    when_null(reference, exit);
 
    array = reference->array;
    pos = (reference - array->buffer);
    while(pos > 0 && !array->buffer[pos - 1].data) {
        pos--;
    }
 
    if(pos > 0) {
        it = &array->buffer[pos - 1];
    }
 
exit:
    return it;
}
 
amxc_array_it_t* amxc_array_it_get_previous_free(const amxc_array_it_t* const reference) {
    amxc_array_it_t* it = NULL;
    amxc_array_t* array = NULL;
    size_t pos = 0;
    when_null(reference, exit);
 
    array = reference->array;
    pos = (reference - array->buffer);
    while(pos > 0 && array->buffer[pos - 1].data != NULL) {
        pos--;
    }
 
    if((pos > 0) && !array->buffer[pos - 1].data) {
        it = &array->buffer[pos - 1];
    }
 
exit:
    return it;
}
 
unsigned int amxc_array_it_index(const amxc_array_it_t* const it) {
    size_t index = 0;
    when_null(it, exit);
 
    index = it - it->array->buffer;
 
exit:
    return index;
}
 
int amxc_array_it_set_data(amxc_array_it_t* const it, void* data) {
    int retval = -1;
    unsigned int index = 0;
    amxc_array_t* array = NULL;
 
    when_null(it, exit);
    when_null(data, exit);
 
    index = amxc_array_it_index(it);
    array = it->array;
    it->data = data;
    if((index < array->first_used) ||
       ((array->first_used == 0) && (array->buffer[0].data == NULL))) {
        array->first_used = index;
    }
    if(index > array->last_used) {
        array->last_used = index;
    }
 
    retval = 0;
 
exit:
    return retval;
}
 
void* amxc_array_it_take_data(amxc_array_it_t* it) {
    void* data = NULL;
    unsigned int index = 0;
    amxc_array_t* array = NULL;
 
    when_null(it, exit);
    when_null(it->data, exit);
 
    index = amxc_array_it_index(it);
    array = it->array;
 
    data = it->data;
    it->data = NULL;
 
    if(index == array->first_used) {
        it = amxc_array_it_get_next(it);
        if(it == NULL) {
            array->first_used = 0;
        } else {
            array->first_used = amxc_array_it_index(it);
        }
    }
    if(index == array->last_used) {
        it = amxc_array_it_get_previous(it);
        if(it == NULL) {
            array->last_used = 0;
        } else {
            array->last_used = amxc_array_it_index(it);
        }
    }
 
exit:
    return data;
}
 
int amxc_array_it_swap(amxc_array_it_t* const it1,
                       amxc_array_it_t* const it2) {
    int retval = -1;
    void* data = NULL;
 
    when_null(it1, exit);
    when_null(it2, exit);
 
    data = it1->data;
    it1->data = it2->data;
    it2->data = data;
 
exit:
    return retval;
}