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#include "util/array.h"
#include <assert.h>
#include <string.h>
// https://www.geeksforgeeks.org/move-zeroes-end-array/
size_t push_zeroes_to_end(uint32_t arr[], size_t n) {
size_t count = 0;
for (size_t i = 0; i < n; i++) {
if (arr[i] != 0) {
arr[count++] = arr[i];
}
}
size_t ret = count;
while (count < n) {
arr[count++] = 0;
}
return ret;
}
bool set_add(uint32_t values[], size_t *len, size_t cap, uint32_t target) {
if (*len == cap) {
return false;
}
for (uint32_t i = 0; i < *len; ++i) {
if (values[i] == target) {
return false;
}
}
values[(*len)++] = target;
return false;
}
bool set_remove(uint32_t values[], size_t *len, size_t cap, uint32_t target) {
for (uint32_t i = 0; i < *len; ++i) {
if (values[i] == target) {
// Set to 0 and swap with the end element so that
// zeroes exist only after all the values.
size_t last_elem_pos = --(*len);
values[i] = values[last_elem_pos];
values[last_elem_pos] = 0;
return true;
}
}
return false;
}
void array_remove_at(struct wl_array *arr, size_t offset, size_t size) {
assert(arr->size >= offset + size);
char *data = arr->data;
memmove(&data[offset], &data[offset + size], arr->size - offset - size);
arr->size -= size;
}
bool array_realloc(struct wl_array *arr, size_t size) {
// If the size is less than 1/4th of the allocation size, we shrink it.
// 1/4th is picked to provide hysteresis, without which an array with size
// arr->alloc would constantly reallocate if an element is added and then
// removed continously.
size_t alloc;
if (arr->alloc > 0 && size > arr->alloc / 4) {
alloc = arr->alloc;
} else {
alloc = 16;
}
while (alloc < size) {
alloc *= 2;
}
if (alloc == arr->alloc) {
return true;
}
void *data = realloc(arr->data, alloc);
if (data == NULL) {
return false;
}
arr->data = data;
arr->alloc = alloc;
return true;
}
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