/***********************************************************************
* *
* This software is part of the ast package *
* Copyright (c) 1985-2010 AT&T Intellectual Property *
* and is licensed under the *
* Common Public License, Version 1.0 *
* by AT&T Intellectual Property *
* *
* A copy of the License is available at *
* http://www.opensource.org/licenses/cpl1.0.txt *
* (with md5 checksum 059e8cd6165cb4c31e351f2b69388fd9) *
* *
* Information and Software Systems Research *
* AT&T Research *
* Florham Park NJ *
* *
* Glenn Fowler <gsf@research.att.com> *
* David Korn <dgk@research.att.com> *
* Phong Vo <kpv@research.att.com> *
* *
***********************************************************************/
#pragma prototyped
/*
* Glenn Fowler
* AT&T Bell Laboratories
*
* return path to file a/b with access mode using : separated dirs
* both a and b may be 0
* if a==".." then relative paths in dirs are ignored
* if (mode&PATH_REGULAR) then path must not be a directory
* if (mode&PATH_ABSOLUTE) then path must be rooted
* path returned in path buffer
*/
#include <ast.h>
char*
pathaccess(register char* path, register const char* dirs, const char* a, const char* b, register int mode)
{
int sib = a && a[0] == '.' && a[1] == '.' && a[2] == 0;
int sep = ':';
char cwd[PATH_MAX];
do
{
dirs = pathcat(path, dirs, sep, a, b);
pathcanon(path, 0);
if ((!sib || *path == '/') && pathexists(path, mode))
{
if (*path == '/' || !(mode & PATH_ABSOLUTE))
return path;
dirs = getcwd(cwd, sizeof(cwd));
sep = 0;
}
} while (dirs);
return 0;
}