/* gawkmisc.c --- miscellaneous gawk routines that are OS specific.

   Copyright (C) 1986, 1988, 1989, 1991 - 1998, 2001 - 2004, 2011

   the Free Software Foundation, Inc.

   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; either version 2, or (at your option)

   any later version.

   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.  */

#ifdef __CYGWIN__

#include <stdio.h>

#include <windows.h>

#include <sys/cygwin.h>

#include <io.h>

#endif

char quote = '\'';

char *defpath = DEFPATH;

char *deflibpath = DEFLIBPATH;

char envsep = ':';

#ifndef INVALID_HANDLE

/* FIXME: is this value for INVALID_HANDLE correct? */

#define INVALID_HANDLE -1

#endif

/* gawk_name --- pull out the "gawk" part from how the OS called us */

char *

gawk_name(const char *filespec)

{

	char *p;

	/* "path/name" -> "name" */

	p = strrchr(filespec, '/');

	return (p == NULL ? (char *) filespec : p + 1);

}

/* os_arg_fixup --- fixup the command line */

void

os_arg_fixup(int *argcp, char ***argvp)

{

	/* no-op */

	return;

}

/* os_devopen --- open special per-OS devices */

int

os_devopen(const char *name, int flag)

{

	/* no-op */

	return INVALID_HANDLE;

}

/* optimal_bufsize --- determine optimal buffer size */

/*

 * Enhance this for debugging purposes, as follows:

 *

 * Always stat the file, stat buffer is used by higher-level code.

 *

 * if (AWKBUFSIZE == "exact")

 * 	return the file size

 * else if (AWKBUFSIZE == a number)

 * 	always return that number

 * else

 * 	if the size is < default_blocksize

 * 		return the size

 *	else

 *		return default_blocksize

 *	end if

 * endif

 *

 * Hair comes in an effort to only deal with AWKBUFSIZE

 * once, the first time this routine is called, instead of

 * every time.  Performance, dontyaknow.

 */

size_t

optimal_bufsize(int fd, struct stat *stb)

{

	char *val;

	static size_t env_val = 0;

	static bool first = true;

	static bool exact = false;

	/* force all members to zero in case OS doesn't use all of them. */

	memset(stb, '\0', sizeof(struct stat));

	/* always stat, in case stb is used by higher level code. */

	if (fstat(fd, stb) == -1)

		fatal("can't stat fd %d (%s)", fd, strerror(errno));

	if (first) {

		first = false;

		if ((val = getenv("AWKBUFSIZE")) != NULL) {

			if (strcmp(val, "exact") == 0)

				exact = true;

			else if (isdigit((unsigned char) *val)) {

				for (; *val && isdigit((unsigned char) *val); val++)

					env_val = (env_val * 10) + *val - '0';

				return env_val;

			}

		}

	} else if (! exact && env_val > 0)

		return env_val;

	/* else

	  	fall through */

	/*

	 * System V.n, n < 4, doesn't have the file system block size in the

	 * stat structure. So we have to make some sort of reasonable

	 * guess. We use stdio's BUFSIZ, since that is what it was

	 * meant for in the first place.

	 */

#ifdef HAVE_STRUCT_STAT_ST_BLKSIZE

#define DEFBLKSIZE	(stb->st_blksize > 0 ? stb->st_blksize : BUFSIZ)

#else

#define DEFBLKSIZE	BUFSIZ

#endif

	if (S_ISREG(stb->st_mode)		/* regular file */

	    && 0 < stb->st_size			/* non-zero size */

	    && (stb->st_size < DEFBLKSIZE	/* small file */

		|| exact))			/* or debugging */

		return stb->st_size;		/* use file size */

	return DEFBLKSIZE;

}

/* ispath --- return true if path has directory components */

int

ispath(const char *file)

{

	return (strchr(file, '/') != NULL);

}

/* isdirpunct --- return true if char is a directory separator */

int

isdirpunct(int c)

{

	return (c == '/');

}

/* os_close_on_exec --- set close on exec flag, print warning if fails */

void

os_close_on_exec(int fd, const char *name, const char *what, const char *dir)

{

	int curflags = 0;

	if (fd <= 2)	/* sanity */

		return;

	/*

	 * Per POSIX, use Read/Modify/Write - get the flags,

	 * add FD_CLOEXEC, set the flags back.

	 */

	if ((curflags = fcntl(fd, F_GETFD)) < 0) {

		warning(_("%s %s `%s': could not get fd flags: (fcntl F_GETFD: %s)"),

			what, dir, name, strerror(errno));

		return;

	}

#ifndef FD_CLOEXEC

#define FD_CLOEXEC	1

#endif

	curflags |= FD_CLOEXEC;

	if (fcntl(fd, F_SETFD, curflags) < 0)

		warning(_("%s %s `%s': could not set close-on-exec: (fcntl F_SETFD: %s)"),

			what, dir, name, strerror(errno));

}

/* os_isdir --- is this an fd on a directory? */

#if ! defined(S_ISDIR) && defined(S_IFDIR)

#define	S_ISDIR(m) (((m) & S_IFMT) == S_IFDIR)

#endif

int

os_isdir(int fd)

{

	struct stat sbuf;

	return (fstat(fd, &sbuf) == 0 && S_ISDIR(sbuf.st_mode));

}

/* os_isreadable --- fd can be read from */

int

os_isreadable(const awk_input_buf_t *iobuf, bool *isdir)

{

	*isdir = false;

	if (iobuf->fd == INVALID_HANDLE)

		return false;

	switch (iobuf->sbuf.st_mode & S_IFMT) {

	case S_IFREG:

	case S_IFCHR:	/* ttys, /dev/null, .. */

#ifdef S_IFSOCK

	case S_IFSOCK:

#endif

#ifdef S_IFIFO

	case S_IFIFO:

#endif

		return true;

	case S_IFDIR:

		*isdir = true;

		/* fall through */

	default:

		return false;

	}

}

/* os_is_setuid --- true if running setuid root */

int

os_is_setuid()

{

	long uid, euid;

	uid = getuid();

	euid = geteuid();

	return (euid == 0 && euid != uid);

}

/* os_setbinmode --- set binary mode on file */

int

os_setbinmode(int fd, int mode)

{

#ifdef __CYGWIN__

	setmode (fd, mode);

#endif

	return 0;

}

/* os_restore_mode --- restore the original mode of the console device */

void

os_restore_mode(int fd)

{

	/* no-op */

	return;

}

/* os_isatty --- return true if fd is a tty */

int

os_isatty(int fd)

{

	return isatty(fd);

}

/* files_are_same --- return true if files are identical */

int

files_are_same(char *path, SRCFILE *src)

{

	struct stat st;

	return (stat(path, & st) == 0

		&& st.st_dev == src->sbuf.st_dev

		&& st.st_ino == src->sbuf.st_ino);

}

void

init_sockets(void)

{

}