xpcom/ds/nsQuickSort.cpp
author Petru Lingurar <petru.lingurar@softvision.ro>
Fri, 13 Jul 2018 17:16:37 +0300
changeset 426733 c2b1f1b52866d2c58f5e23fe2df97c9127ebcacf
parent 330842 a3af628d69b3f4d4f029d5f9118dd44bf1fadbd3
child 448947 6f3709b3878117466168c40affa7bca0b60cf75b
permissions -rw-r--r--
Bug 1385464 - Start using support library v. 26; r=nalexander This patch also: Resolves missing resources and api changes - LeanplumActionBarActivity was removed because Support Library 26 deprecated ActionBarActivity. Class was already not in use. - CustomTabsService added two new methods which we need to override. Tested to make sure that previous functionality was maintained but with the addition of the two new methods maybe that feature could be improved. - For checking layout direction we'll use our own new method from ViewUtil which mimics what the now restricted method from the support library would do. - Upgraded to use AppCompatResources#getDrawable(..) in place of the now restricted AppCompatDrawableManager.get().getDrawable(..). Resolves obscure leaks and crashes after the upgrade - LoaderManager.destroyLoader(..) was added before the existing call to LoaderManager.restartLoader(..) to prevent potential Cursor leaks - Disable website suggestions depending on the address bar inputs when running in automation to avoid Robocop tests failing (they were entering serially maybe 100 characters in <5 ms which created around that many new Threads, operation that could cause the Executor to throw a RejectedExecutionException) At the moment this functionality is not covered by tests anyway and it was the only fix I could find that would not involve changing the whole implemenation for address bar suggestions, implementation which in the real world works ok. MozReview-Commit-ID: 2fX1SBHiSh0

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */

/*-
 * Copyright (c) 1992, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

/* We need this because Solaris' version of qsort is broken and
 * causes array bounds reads.
 */

#include <stdlib.h>
#include "nsAlgorithm.h"
#include "nsQuickSort.h"

extern "C" {

#if !defined(DEBUG) && (defined(__cplusplus) || defined(__gcc))
# ifndef INLINE
#  define INLINE inline
# endif
#else
# define INLINE
#endif

typedef int		 cmp_t(const void *, const void *, void *);
static INLINE char	*med3(char *, char *, char *, cmp_t *, void *);
static INLINE void	swapfunc(char *, char *, int, int);

/*
 * Qsort routine from Bentley & McIlroy's "Engineering a Sort Function".
 */
#define swapcode(TYPE, parmi, parmj, n) { 		\
	long i = (n) / sizeof (TYPE); 			\
	TYPE *pi = (TYPE *) (parmi); 			\
	TYPE *pj = (TYPE *) (parmj); 			\
	do { 						\
		TYPE	t = *pi;			\
		*pi++ = *pj;				\
		*pj++ = t;				\
        } while (--i > 0);				\
}

#define SWAPINIT(a, es) swaptype = ((char *)a - (char *)0) % sizeof(long) || \
	es % sizeof(long) ? 2 : es == sizeof(long)? 0 : 1;

static INLINE void
swapfunc(char *a, char *b, int n, int swaptype)
{
	if(swaptype <= 1)
		swapcode(long, a, b, n)
	else
		swapcode(char, a, b, n)
}

#define swap(a, b)					\
	if (swaptype == 0) {				\
		long t = *(long *)(a);			\
		*(long *)(a) = *(long *)(b);		\
		*(long *)(b) = t;			\
	} else						\
		swapfunc((char *)a, (char*)b, (int)es, swaptype)

#define vecswap(a, b, n) 	if ((n) > 0) swapfunc((char *)a, (char *)b, (int)n, swaptype)

static INLINE char *
med3(char *a, char *b, char *c, cmp_t* cmp, void *data)
{
	return cmp(a, b, data) < 0 ?
	       (cmp(b, c, data) < 0 ? b : (cmp(a, c, data) < 0 ? c : a ))
              :(cmp(b, c, data) > 0 ? b : (cmp(a, c, data) < 0 ? a : c ));
}

void NS_QuickSort (
	void *a,
	unsigned int n,
    unsigned int es,
	cmp_t *cmp,
	void *data
    )
{
	char *pa, *pb, *pc, *pd, *pl, *pm, *pn;
	int d, r, swaptype;

loop:	SWAPINIT(a, es);
	/* Use insertion sort when input is small */
	if (n < 7) {
		for (pm = (char *)a + es; pm < (char *)a + n * es; pm += es)
			for (pl = pm; pl > (char *)a && cmp(pl - es, pl, data) > 0;
			     pl -= es)
				swap(pl, pl - es);
		return;
	}
	/* Choose pivot */
	pm = (char *)a + (n / 2) * es;
	if (n > 7) {
		pl = (char *)a;
		pn = (char *)a + (n - 1) * es;
		if (n > 40) {
			d = (n / 8) * es;
			pl = med3(pl, pl + d, pl + 2 * d, cmp, data);
			pm = med3(pm - d, pm, pm + d, cmp, data);
			pn = med3(pn - 2 * d, pn - d, pn, cmp, data);
		}
		pm = med3(pl, pm, pn, cmp, data);
	}
	swap(a, pm);
	pa = pb = (char *)a + es;

	pc = pd = (char *)a + (n - 1) * es;
	/* loop invariants:
	 * [a, pa) = pivot
	 * [pa, pb) < pivot
	 * [pb, pc + es) unprocessed
	 * [pc + es, pd + es) > pivot
	 * [pd + es, pn) = pivot
	 */
	for (;;) {
		while (pb <= pc && (r = cmp(pb, a, data)) <= 0) {
			if (r == 0) {
				swap(pa, pb);
				pa += es;
			}
			pb += es;
		}
		while (pb <= pc && (r = cmp(pc, a, data)) >= 0) {
			if (r == 0) {
				swap(pc, pd);
				pd -= es;
			}
			pc -= es;
		}
		if (pb > pc)
			break;
		swap(pb, pc);
		pb += es;
		pc -= es;
	}
	/* Move pivot values */
	pn = (char *)a + n * es;
	r = XPCOM_MIN(pa - (char *)a, pb - pa);
	vecswap(a, pb - r, r);
	r = XPCOM_MIN<size_t>(pd - pc, pn - pd - es);
	vecswap(pb, pn - r, r);
	/* Recursively process partitioned items */
	if ((r = pb - pa) > (int)es)
        NS_QuickSort(a, r / es, es, cmp, data);
	if ((r = pd - pc) > (int)es) {
		/* Iterate rather than recurse to save stack space */
		a = pn - r;
		n = r / es;
		goto loop;
	}
/*		NS_QuickSort(pn - r, r / es, es, cmp, data);*/
}

}

#undef INLINE
#undef swapcode
#undef SWAPINIT
#undef swap
#undef vecswap