pathprog.c revision 34f9b3eef6fdadbda0a846aa4d68691ac40eace5
/***********************************************************************
* *
* This software is part of the ast package *
* Copyright (c) 1985-2009 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 Research
*
* return the full path of the current program in path
* command!=0 is used as a default
*/
#include <ast.h>
#if _WINIX
#include <ast_windows.h>
#include <ctype.h>
#endif
#include "FEATURE/prog"
static size_t
prog(const char* command, char* path, size_t size)
{
ssize_t n;
#if _WINIX || _lib_getexecname
char* s;
#endif
#if _WINIX
char* t;
char* e;
int c;
int q;
#endif
#ifdef _PROC_PROG
if ((n = readlink(_PROC_PROG, path, size)) > 0)
{
if (n < size)
path[n] = 0;
return n;
}
#endif
#if _lib_getexecname
if (s = (char*)getexecname())
{
n = strlen(s);
if (n < size)
strcpy(path, s);
return n;
}
#endif
#if _WINIX
if (s = GetCommandLine())
{
n = 0;
q = 0;
t = path;
e = path + size - 1;
while (c = *s++)
{
if (c == q)
q = 0;
else if (!q && c == '"')
q = c;
else if (!q && isspace(c))
break;
else if (t < e)
*t++ = c == '\\' ? '/' : c;
else
n++;
}
if (t < e)
*t = 0;
return (t - path) + n;
}
#endif
if (command)
{
if ((n = strlen(command) + 1) <= size)
memcpy(path, command, n);
return n;
}
return 0;
}
size_t
pathprog(const char* command, char* path, size_t size)
{
ssize_t n;
char buf[PATH_MAX];
if ((n = prog(command, path, size)) > 0 && n <= size && *path != '/')
{
if (!pathpath(buf, path, NiL, PATH_REGULAR|PATH_EXECUTE))
n = 0;
else if ((n = strlen(buf) + 1) <= size)
memcpy(path, buf, n);
}
return n;
}