cosmopolitan/libc/calls/getcwd.c

58 lines
2.9 KiB
C

/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
│vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8 :vi│
╞══════════════════════════════════════════════════════════════════════════════╡
│ Copyright 2020 Justine Alexandra Roberts Tunney │
│ │
│ 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 2 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, write to the Free Software │
│ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA │
│ 02110-1301 USA │
╚─────────────────────────────────────────────────────────────────────────────*/
#include "libc/calls/calls.h"
#include "libc/calls/internal.h"
#include "libc/dce.h"
#include "libc/errno.h"
#include "libc/sysv/errfuns.h"
/**
* Returns current working directory.
*
* @param buf is where UTF-8 NUL-terminated path string gets written,
* which may be NULL to ask this function to malloc a buffer
* @param size is number of bytes available in buf, e.g. PATH_MAX,
* which may be 0 if buf NULL
* @return buf containing system-normative path or NULL w/ errno
* @see get_current_dir_name() which is better
* @error ERANGE, EINVAL
*/
char *(getcwd)(char *buf, size_t size) {
buf[0] = '\0';
if (!IsWindows()) {
int olderr = errno;
if (getcwd$sysv(buf, size) != NULL) {
return buf;
} else if (IsXnu() && errno == ENOSYS) {
if (size >= 2) {
buf[0] = '.'; /* XXX: could put forth more effort */
buf[1] = '\0';
errno = olderr;
return buf;
} else {
erange();
}
}
return NULL;
} else {
return getcwd$nt(buf, size);
}
}