1N/A/***********************************************************************
1N/A* *
1N/A* This software is part of the ast package *
1N/A* Copyright (c) 1985-2011 AT&T Intellectual Property *
1N/A* and is licensed under the *
1N/A* Common Public License, Version 1.0 *
1N/A* by AT&T Intellectual Property *
1N/A* *
1N/A* A copy of the License is available at *
1N/A* http://www.opensource.org/licenses/cpl1.0.txt *
1N/A* (with md5 checksum 059e8cd6165cb4c31e351f2b69388fd9) *
1N/A* *
1N/A* Information and Software Systems Research *
1N/A* AT&T Research *
1N/A* Florham Park NJ *
1N/A* *
1N/A* Glenn Fowler <gsf@research.att.com> *
1N/A* David Korn <dgk@research.att.com> *
1N/A* Phong Vo <kpv@research.att.com> *
1N/A* *
1N/A***********************************************************************/
1N/A#pragma prototyped
1N/A
1N/A#include <ast.h>
1N/A
1N/A/*
1N/A * return small format buffer chunk of size n
1N/A * spin lock for thread access
1N/A * format buffers are short lived
1N/A * only one concurrent buffer with size > sizeof(buf)
1N/A */
1N/A
1N/Astatic char buf[16 * 1024];
1N/Astatic char* nxt = buf;
1N/Astatic int lck = -1;
1N/A
1N/Astatic char* big;
1N/Astatic size_t bigsiz;
1N/A
1N/Achar*
1N/Afmtbuf(size_t n)
1N/A{
1N/A register char* cur;
1N/A
1N/A while (++lck)
1N/A lck--;
1N/A if (n > (&buf[elementsof(buf)] - nxt))
1N/A {
1N/A if (n > elementsof(buf))
1N/A {
1N/A if (n > bigsiz)
1N/A {
1N/A bigsiz = roundof(n, 8 * 1024);
1N/A if (!(big = newof(big, char, bigsiz, 0)))
1N/A {
1N/A lck--;
1N/A return 0;
1N/A }
1N/A }
1N/A lck--;
1N/A return big;
1N/A }
1N/A nxt = buf;
1N/A }
1N/A cur = nxt;
1N/A nxt += n;
1N/A lck--;
1N/A return cur;
1N/A}