void qsort_s(void *Base,
size_t NumOfElements,
size_t SizeOfElements,
int (__cdecl *FuncCompare)(void *,const void *,const void *),
void *Context)
{
if (!FuncCompare)
return;
const size_t size = NumOfElements * SizeOfElements;
char buf[1024];
if (size < sizeof(buf))
{
/* The temporary array fits on the small on-stack buffer. */
msort_with_tmp(Base, NumOfElements, SizeOfElements, FuncCompare, Context, buf);
}
else
{
/* It's somewhat large, so malloc it. */
char *tmp = malloc(size);
if (tmp)
{
msort_with_tmp(Base, NumOfElements, SizeOfElements, FuncCompare, Context, tmp);
free(tmp);
}
}
}
static void
msort_with_tmp (void *b, size_t n, size_t s, __compar_fn_t cmp,
char *t)
{
char *tmp;
char *b1, *b2;
size_t n1, n2;
if (n <= 1)
return;
n1 = n / 2;
n2 = n - n1;
b1 = b;
b2 = (char *) b + (n1 * s);
msort_with_tmp (b1, n1, s, cmp, t);
msort_with_tmp (b2, n2, s, cmp, t);
tmp = t;
if (s == OPSIZ && (b1 - (char *) 0) % OPSIZ == 0)
/* We are operating on aligned words. Use direct word stores. */
while (n1 > 0 && n2 > 0)
{
if ((*cmp) (b1, b2) <= 0)
{
--n1;
*((op_t *) tmp)++ = *((op_t *) b1)++;
}
else
{
--n2;
*((op_t *) tmp)++ = *((op_t *) b2)++;
}
}
else
while (n1 > 0 && n2 > 0)
{
if ((*cmp) (b1, b2) <= 0)
{
tmp = (char *) __mempcpy (tmp, b1, s);
b1 += s;
--n1;
}
else
{
tmp = (char *) __mempcpy (tmp, b2, s);
b2 += s;
--n2;
}
}
if (n1 > 0)
memcpy (tmp, b1, n1 * s);
memcpy (b, t, (n - n2) * s);
}
static
void
msort_with_tmp( void *Base,
size_t NumElem,
size_t SizeElem,
int (*FuncCmp)(void *Ctx, const void *, const void *),
void *Context,
char *ExtTmp)
{
char *LocalTmp;
char *b1, *b2;
size_t n1, n2;
if (NumElem <= 1)
return;
n1 = NumElem / 2;
n2 = NumElem - n1;
b1 = Base;
b2 = (char *)Base + (n1 * SizeElem);
msort_with_tmp(b1, n1, SizeElem, FuncCmp, Context, ExtTmp);
msort_with_tmp(b2, n2, SizeElem, FuncCmp, Context, ExtTmp);
LocalTmp = ExtTmp;
while (n1 > 0 && n2 > 0)
{
if (FuncCmp(Context, b1, b2) <= 0)
{
memcpy(LocalTmp, b1, SizeElem);
LocalTmp += SizeElem;
b1 += SizeElem;
--n1;
}
else
{
memcpy(LocalTmp, b2, SizeElem);
LocalTmp += SizeElem;
b2 += SizeElem;
--n2;
}
}
if (n1 > 0)
memcpy(LocalTmp, b1, n1 * SizeElem);
memcpy(Base, ExtTmp, (NumElem - n2) * SizeElem);
}
void git_qsort(void *b, size_t n, size_t s,
int (*cmp)(const void *, const void *))
{
const size_t size = n * s;
char buf[1024];
if (size < sizeof(buf)) {
/* The temporary array fits on the small on-stack buffer. */
msort_with_tmp(b, n, s, cmp, buf);
} else {
/* It's somewhat large, so malloc it. */
char *tmp = xmalloc(size);
msort_with_tmp(b, n, s, cmp, tmp);
free(tmp);
}
}
static void msort_with_tmp(void *b, size_t n, size_t s,
int (*cmp)(const void *, const void *),
char *t)
{
char *tmp;
char *b1, *b2;
size_t n1, n2;
if (n <= 1)
return;
n1 = n / 2;
n2 = n - n1;
b1 = b;
b2 = (char *)b + (n1 * s);
msort_with_tmp(b1, n1, s, cmp, t);
msort_with_tmp(b2, n2, s, cmp, t);
tmp = t;
while (n1 > 0 && n2 > 0) {
if (cmp(b1, b2) <= 0) {
memcpy(tmp, b1, s);
tmp += s;
b1 += s;
--n1;
} else {
memcpy(tmp, b2, s);
tmp += s;
b2 += s;
--n2;
}
}
if (n1 > 0)
memcpy(tmp, b1, n1 * s);
memcpy(b, t, (n - n2) * s);
}
void qsort(void *base, size_t total_num, size_t size,
int (*cmp)(const void *, const void *))
{
size_t total_size = size * total_num;
if(total_size < 1024)
{
msort_with_tmp(base, total_num, size, cmp, (char*)alloca(total_size) );
}
else
{
char *tmp = (char*)malloc(size);
if(tmp == NULL)
{
extern void _quicksort(void *base, size_t total_num, size_t size, int (*compare)(const void *, const void *) );
_quicksort(base, total_num, size, cmp);
}
else
{
msort_with_tmp(base, total_num, size, cmp, tmp );
free( tmp );
}
}
}
void msort_with_tmp(void *base, size_t num, size_t size,
int (*compare)(const void *, const void *),
char *t)
{
if( num <= 1)
return;
int num1 = num / 2;
char *base1 = (char*)base;
int num2 = num - num1;
char *base2 = (char*)base + size * num1;
msort_with_tmp(base1, num1, size, compare, t);
msort_with_tmp(base2, num2, size, compare, t);
char *tmp = t;
while(num1 > 0 && num2 > 0)
{
if( (*compare)(base1, base2) <= 0)
{
memcpy(tmp, base1, size);
base1 += size;
--num1;
}
else
{
memcpy(tmp, base2, size);
base2 += size;
--num2;
}
tmp += size;
}
if(num1 > 0)
memcpy(tmp, base1, num1 * size); //base1 | base2， base2's elem is tail and sorted
memcpy(base, t, (num - num2) * size);
}
static void
msort_with_tmp (const struct msort_param *p, void *b, size_t n)
{
char *b1, *b2;
size_t n1, n2;
if (n <= 1)
return;
n1 = n / 2;
n2 = n - n1;
b1 = b;
b2 = (char *) b + (n1 * p->s);
msort_with_tmp (p, b1, n1);
msort_with_tmp (p, b2, n2);
char *tmp = p->t;
const size_t s = p->s;
__compar_d_fn_t cmp = p->cmp;
void *arg = p->arg;
switch (p->var)
{
case 0:
while (n1 > 0 && n2 > 0)
{
if ((*cmp) (b1, b2, arg) <= 0)
{
*(uint32_t *) tmp = *(uint32_t *) b1;
b1 += sizeof (uint32_t);
--n1;
}
else
{
*(uint32_t *) tmp = *(uint32_t *) b2;
b2 += sizeof (uint32_t);
--n2;
}
tmp += sizeof (uint32_t);
}
break;
case 1:
while (n1 > 0 && n2 > 0)
{
if ((*cmp) (b1, b2, arg) <= 0)
{
*(uint64_t *) tmp = *(uint64_t *) b1;
b1 += sizeof (uint64_t);
--n1;
}
else
{
*(uint64_t *) tmp = *(uint64_t *) b2;
b2 += sizeof (uint64_t);
--n2;
}
tmp += sizeof (uint64_t);
}
break;
case 2:
while (n1 > 0 && n2 > 0)
{
unsigned long *tmpl = (unsigned long *) tmp;
unsigned long *bl;
tmp += s;
if ((*cmp) (b1, b2, arg) <= 0)
{
bl = (unsigned long *) b1;
b1 += s;
--n1;
}
else
{
bl = (unsigned long *) b2;
b2 += s;
--n2;
}
while (tmpl < (unsigned long *) tmp)
*tmpl++ = *bl++;
}
break;
case 3:
while (n1 > 0 && n2 > 0)
{
if ((*cmp) (*(const void **) b1, *(const void **) b2, arg) <= 0)
{
*(void **) tmp = *(void **) b1;
b1 += sizeof (void *);
--n1;
}
else
{
*(void **) tmp = *(void **) b2;
b2 += sizeof (void *);
--n2;
}
tmp += sizeof (void *);
}
break;
default:
while (n1 > 0 && n2 > 0)
{
if ((*cmp) (b1, b2, arg) <= 0)
{
tmp = (char *) __mempcpy (tmp, b1, s);
b1 += s;
--n1;
}
else
{
tmp = (char *) __mempcpy (tmp, b2, s);
b2 += s;
--n2;
}
}
break;
}
if (n1 > 0)
memcpy (tmp, b1, n1 * s);
memcpy (b, p->t, (n - n2) * s);
}
void
qsort (void *b, size_t n, size_t s, __compar_fn_t cmp)
{
const size_t size = n * s;
if (size < 1024)
{
void *buf = __alloca (size);
/* The temporary array is small, so put it on the stack. */
msort_with_tmp (b, n, s, cmp, buf);
}
else
{
/* We should avoid allocating too much memory since this might
have to be backed up by swap space. */
static long int phys_pages;
static int pagesize;
if (phys_pages == 0)
{
phys_pages = __sysconf (_SC_PHYS_PAGES);
if (phys_pages == -1)
/* Error while determining the memory size. So let's
assume there is enough memory. Otherwise the
implementer should provide a complete implementation of
the `sysconf' function. */
phys_pages = (long int) (~0ul >> 1);
/* The following determines that we will never use more than
a quarter of the physical memory. */
phys_pages /= 4;
pagesize = __sysconf (_SC_PAGESIZE);
}
/* Just a comment here. We cannot compute
phys_pages * pagesize
and compare the needed amount of memory against this value.
The problem is that some systems might have more physical
memory then can be represented with a `size_t' value (when
measured in bytes. */
/* If the memory requirements are too high don't allocate memory. */
if (size / pagesize > phys_pages)
_quicksort (b, n, s, cmp);
else
{
/* It's somewhat large, so malloc it. */
int save = errno;
char *tmp = malloc (size);
if (tmp == NULL)
{
/* Couldn't get space, so use the slower algorithm
that doesn't need a temporary array. */
__set_errno (save);
_quicksort (b, n, s, cmp);
}
else
{
__set_errno (save);
msort_with_tmp (b, n, s, cmp, tmp);
free (tmp);
}
}
}
