array.c 文件
/* {{{ proto bool sort(array &array_arg [, int sort_flags])
Sort an array */
PHP_FUNCTION(sort)
{
zval *array;
zend_long sort_type = PHP_SORT_REGULAR;
compare_func_t cmp;
ZEND_PARSE_PARAMETERS_START(1, 2)
Z_PARAM_ARRAY_EX(array, 0, 1)
Z_PARAM_OPTIONAL
Z_PARAM_LONG(sort_type)
ZEND_PARSE_PARAMETERS_END_EX(RETURN_FALSE);
cmp = php_get_data_compare_func(sort_type, 0);
if (zend_hash_sort(Z_ARRVAL_P(array), cmp, 1) == FAILURE) {
RETURN_FALSE;
}
RETURN_TRUE;
}
/* }}} */
根据上述代码，查找 zend_hash_sort 函数，找到 zend_hash.h && zend_hash.c
zend_hash.h，zend_hash_sort 函数在 zend_hash.c 实现
/* Copying, merging and sorting */
ZEND_API void ZEND_FASTCALL zend_hash_copy(HashTable *target, HashTable *source, copy_ctor_func_t pCopyConstructor);
ZEND_API void ZEND_FASTCALL zend_hash_merge(HashTable *target, HashTable *source, copy_ctor_func_t pCopyConstructor, zend_bool overwrite);
ZEND_API void ZEND_FASTCALL zend_hash_merge_ex(HashTable *target, HashTable *source, copy_ctor_func_t pCopyConstructor, merge_checker_func_t pMergeSource, void *pParam);
ZEND_API void zend_hash_bucket_swap(Bucket *p, Bucket *q);
ZEND_API void zend_hash_bucket_renum_swap(Bucket *p, Bucket *q);
ZEND_API void zend_hash_bucket_packed_swap(Bucket *p, Bucket *q);
ZEND_API int zend_hash_compare(HashTable *ht1, HashTable *ht2, compare_func_t compar, zend_bool ordered);
ZEND_API int ZEND_FASTCALL zend_hash_sort_ex(HashTable *ht, sort_func_t sort_func, compare_func_t compare_func, zend_bool renumber);
ZEND_API zval* ZEND_FASTCALL zend_hash_minmax(const HashTable *ht, compare_func_t compar, uint32_t flag);
#define zend_hash_sort(ht, compare_func, renumber) \
zend_hash_sort_ex(ht, zend_sort, compare_func, renumber)
zend_hash.c
ZEND_API int ZEND_FASTCALL zend_hash_sort_ex(HashTable *ht, sort_func_t sort, compare_func_t compar, zend_bool renumber)
{
Bucket *p;
uint32_t i, j;
IS_CONSISTENT(ht);
HT_ASSERT_RC1(ht);
if (!(ht->nNumOfElements>1) && !(renumber && ht->nNumOfElements>0)) { /* Doesn't require sorting */
return SUCCESS;
}
if (HT_IS_WITHOUT_HOLES(ht)) {
i = ht->nNumUsed;
} else {
for (j = 0, i = 0; j < ht->nNumUsed; j++) {
p = ht->arData + j;
if (UNEXPECTED(Z_TYPE(p->val) == IS_UNDEF)) continue;
if (i != j) {
ht->arData[i] = *p;
}
i++;
}
}
sort((void *)ht->arData, i, sizeof(Bucket), compar,
(swap_func_t)(renumber? zend_hash_bucket_renum_swap :
((HT_FLAGS(ht) & HASH_FLAG_PACKED) ? zend_hash_bucket_packed_swap : zend_hash_bucket_swap)));
ht->nNumUsed = i;
ht->nInternalPointer = 0;
if (renumber) {
for (j = 0; j < i; j++) {
p = ht->arData + j;
p->h = j;
if (p->key) {
zend_string_release(p->key);
p->key = NULL;
}
}
ht->nNextFreeElement = i;
}
if (HT_FLAGS(ht) & HASH_FLAG_PACKED) {
if (!renumber) {
zend_hash_packed_to_hash(ht);
}
} else {
if (renumber) {
void *new_data, *old_data = HT_GET_DATA_ADDR(ht);
Bucket *old_buckets = ht->arData;
new_data = pemalloc(HT_SIZE_EX(ht->nTableSize, HT_MIN_MASK), (GC_FLAGS(ht) & IS_ARRAY_PERSISTENT));
HT_FLAGS(ht) |= HASH_FLAG_PACKED | HASH_FLAG_STATIC_KEYS;
ht->nTableMask = HT_MIN_MASK;
HT_SET_DATA_ADDR(ht, new_data);
memcpy(ht->arData, old_buckets, sizeof(Bucket) * ht->nNumUsed);
pefree(old_data, GC_FLAGS(ht) & IS_ARRAY_PERSISTENT);
HT_HASH_RESET_PACKED(ht);
} else {
zend_hash_rehash(ht);
}
}
return SUCCESS;
}
由上述代码，我们来看 zend_sort 函数实现。
打开 zend_sort.h && zend_sort.c
zend_sort.h
#ifndef ZEND_SORT_H
#define ZEND_SORT_H
BEGIN_EXTERN_C()
ZEND_API void zend_qsort(void *base, size_t nmemb, size_t siz, compare_func_t cmp, swap_func_t swp);
ZEND_API void zend_sort(void *base, size_t nmemb, size_t siz, compare_func_t cmp, swap_func_t swp);
ZEND_API void zend_insert_sort(void *base, size_t nmemb, size_t siz, compare_func_t cmp, swap_func_t swp);
END_EXTERN_C()
#endif /* ZEND_SORT_H */
zend_sort.c 实现了以上三个函数
qsort
ZEND_API void zend_qsort(void *base, size_t nmemb, size_t siz, compare_func_t compare, swap_func_t swp) /* {{{ */
{
void *begin_stack[QSORT_STACK_SIZE];
void *end_stack[QSORT_STACK_SIZE];
register char *begin;
register char *end;
register char *seg1;
register char *seg2;
register char *seg2p;
register int loop;
size_t offset;
begin_stack[0] = (char *) base;
end_stack[0] = (char *) base + ((nmemb - 1) * siz);
for (loop = 0; loop >= 0; --loop) {
begin = begin_stack[loop];
end = end_stack[loop];
while (begin < end) {
offset = (end - begin) >> Z_L(1);
swp(begin, begin + (offset - (offset % siz)));
seg1 = begin + siz;
seg2 = end;
while (1) {
for (; seg1 < seg2 && compare(begin, seg1) > 0;
seg1 += siz);
for (; seg2 >= seg1 && compare(seg2, begin) > 0;
seg2 -= siz);
if (seg1 >= seg2)
break;
swp(seg1, seg2);
seg1 += siz;
seg2 -= siz;
}
swp(begin, seg2);
seg2p = seg2;
if ((seg2p - begin) <= (end - seg2p)) {
if ((seg2p + siz) < end) {
begin_stack[loop] = seg2p + siz;
end_stack[loop++] = end;
}
end = seg2p - siz;
}
else {
if ((seg2p - siz) > begin) {
begin_stack[loop] = begin;
end_stack[loop++] = seg2p - siz;
}
begin = seg2p + siz;
}
}
}
}
sort
ZEND_API void zend_sort(void *base, size_t nmemb, size_t siz, compare_func_t cmp, swap_func_t swp)
{
while (1) {
if (nmemb <= 16) {
zend_insert_sort(base, nmemb, siz, cmp, swp);
return;
} else {
char *i, *j;
char *start = (char *)base;
char *end = start + (nmemb * siz);
size_t offset = (nmemb >> Z_L(1));
char *pivot = start + (offset * siz);
if ((nmemb >> Z_L(10))) {
size_t delta = (offset >> Z_L(1)) * siz;
zend_sort_5(start, start + delta, pivot, pivot + delta, end - siz, cmp, swp);
} else {
zend_sort_3(start, pivot, end - siz, cmp, swp);
}
swp(start + siz, pivot);
pivot = start + siz;
i = pivot + siz;
j = end - siz;
while (1) {
while (cmp(pivot, i) > 0) {
i += siz;
if (UNEXPECTED(i == j)) {
goto done;
}
}
j -= siz;
if (UNEXPECTED(j == i)) {
goto done;
}
while (cmp(j, pivot) > 0) {
j -= siz;
if (UNEXPECTED(j == i)) {
goto done;
}
}
swp(i, j);
i += siz;
if (UNEXPECTED(i == j)) {
goto done;
}
}
done:
swp(pivot, i - siz);
if ((i - siz) - start < end - i) {
zend_sort(start, (i - start)/siz - 1, siz, cmp, swp);
base = i;
nmemb = (end - i)/siz;
} else {
zend_sort(i, (end - i)/siz, siz, cmp, swp);
nmemb = (i - start)/siz - 1;
}
}
}
}
insert_sort
ZEND_API void zend_insert_sort(void *base, size_t nmemb, size_t siz, compare_func_t cmp, swap_func_t swp) /* {{{ */{
switch (nmemb) {
case 0:
case 1:
break;
case 2:
zend_sort_2(base, (char *)base + siz, cmp, swp);
break;
case 3:
zend_sort_3(base, (char *)base + siz, (char *)base + siz + siz, cmp, swp);
break;
case 4:
{
size_t siz2 = siz + siz;
zend_sort_4(base, (char *)base + siz, (char *)base + siz2, (char *)base + siz + siz2, cmp, swp);
}
break;
case 5:
{
size_t siz2 = siz + siz;
zend_sort_5(base, (char *)base + siz, (char *)base + siz2, (char *)base + siz + siz2, (char *)base + siz2 + siz2, cmp, swp);
}
break;
default:
{
char *i, *j, *k;
char *start = (char *)base;
char *end = start + (nmemb * siz);
size_t siz2= siz + siz;
char *sentry = start + (6 * siz);
for (i = start + siz; i < sentry; i += siz) {
j = i - siz;
if (!(cmp(j, i) > 0)) {
continue;
}
while (j != start) {
j -= siz;
if (!(cmp(j, i) > 0)) {
j += siz;
break;
}
}
for (k = i; k > j; k -= siz) {
swp(k, k - siz);
}
}
for (i = sentry; i < end; i += siz) {
j = i - siz;
if (!(cmp(j, i) > 0)) {
continue;
}
do {
j -= siz2;
if (!(cmp(j, i) > 0)) {
j += siz;
if (!(cmp(j, i) > 0)) {
j += siz;
}
break;
}
if (j == start) {
break;
}
if (j == start + siz) {
j -= siz;
if (cmp(i, j) > 0) {
j += siz;
}
break;
}
} while (1);
for (k = i; k > j; k -= siz) {
swp(k, k - siz);
}
}
}
break;
}
}