utils/src/pwd.c

128 lines
2.2 KiB
C

/* $Id$ */
/* Copyright (c) 2011 Pierre Pronchery <khorben@defora.org> */
/* This file is part of DeforaOS Unix utils */
/* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, version 3 of the License.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>. */
#include <unistd.h>
#include <stdlib.h>
#include <stdio.h>
#include <limits.h>
/* types */
typedef enum _pwd_flag
{
PWD_P = 1,
PWD_LP = 2
} pwd_flag;
/* pwd */
static int _pwd_error(char const * message, int ret);
static int _pwd(pwd_flag pf)
{
char * pwd;
#ifdef PATH_MAX
char buf[PATH_MAX];
#else
char buf[1024];
#endif
char * p;
pwd = getenv("PWD");
if(pf == PWD_LP && pwd != NULL && *pwd == '/')
{
for(p = pwd; *p != '\0'; p++)
{
if(*p != '/')
continue;
if(*++p != '.')
continue;
if(*++p == '\0' || *p == '/')
{
p--;
break;
}
if(*p != '.')
continue;
if(*++p == '\0' || *p == '/')
{
p--;
break;
}
}
if(*p == '\0')
{
printf("%s\n", pwd);
return 0;
}
}
if(pwd != NULL)
{
/* FIXME check for symlinks */
}
else
{
if(getcwd(buf, sizeof(buf) - 1) == NULL)
return _pwd_error("getcwd", 1);
buf[sizeof(buf) - 1] = '\0';
pwd = buf;
}
printf("%s\n", pwd);
return 0;
}
static int _pwd_error(char const * message, int ret)
{
fputs("pwd: ", stderr);
perror(message);
return ret;
}
/* usage */
static int _usage(void)
{
fputs("Usage: pwd [-L|-P]\n\
-L Avoid \".\" or \"..\" filenames\n\
-P Avoid symbolic links\n", stderr);
return 1;
}
/* main */
int main(int argc, char * argv[])
{
pwd_flag pf = PWD_LP;
int o;
while((o = getopt(argc, argv, "LP")) != -1)
switch(o)
{
case 'L':
pf = PWD_LP;
break;
case 'P':
pf = PWD_P;
break;
default:
return _usage();
}
if(optind != argc)
return _usage();
return _pwd(pf) == 0 ? 0 : 2;
}