// sysread.c - interface to system read/write

//

// © Portions Copyright (c) Symbian Software Ltd 2007. All rights reserved.

//

/*

 * This file is part of zsh, the Z shell.

 *

 * Copyright (c) 1998-2003 Peter Stephenson

 * All rights reserved.

 *

 * Permission is hereby granted, without written agreement and without

 * license or royalty fees, to use, copy, modify, and distribute this

 * software and to distribute modified versions of this software for any

 * purpose, provided that the above copyright notice and the following

 * two paragraphs appear in all copies of this software.

 *

 * In no event shall Peter Stephenson or the Zsh Development

 * Group be liable to any party for direct, indirect, special, incidental,

 * or consequential damages arising out of the use of this software and

 * its documentation, even if Peter Stephenson, and the Zsh

 * Development Group have been advised of the possibility of such damage.

 *

 * Peter Stephenson and the Zsh Development Group specifically

 * disclaim any warranties, including, but not limited to, the implied

 * warranties of merchantability and fitness for a particular purpose.  The

 * software provided hereunder is on an "as is" basis, and Peter Stephenson

 * and the Zsh Development Group have no obligation to provide maintenance,

 * support, updates, enhancements, or modifications.

 *

 */

#include "system.mdh"

#include "system.pro"

#ifdef __SYMBIAN32__

#include "dummy.h" //poll

#endif //__SYMBIAN32__

#ifdef HAVE_POLL_H

#ifndef __SYMBIAN32__

# include <sys/poll.h> 

#else 

#include "poll.h"

#endif

#endif

#if defined(HAVE_POLL) && !defined(POLLIN)

# undef HAVE_POLL

#endif

#ifdef __SYMBIAN32__

#ifdef __WINSCW__

#pragma warn_unusedarg off

#endif//__WINSCW__

#endif//__SYMBIAN32__

#define SYSREAD_BUFSIZE	8192

/**/

static int

getposint(char *instr, char *nam)

{

    char *eptr;

    int ret;

    ret = (int)zstrtol(instr, &eptr, 10);

    if (*eptr || ret < 0) {

	zwarnnam(nam, "integer expected: %s", instr, 0);

	return -1;

    }

    return ret;

}

/*

 * Return values of bin_sysread:

 *	0	Successfully read (and written if appropriate)

 *	1	Error in parameters to command

 *	2	Error on read, or polling read fd ) ERRNO set by

 *      3	Error on write			  ) system

 *	4	Timeout on read

 *	5       Zero bytes read, end of file

 */

/**/

static int

bin_sysread(char *nam, char **args, Options ops, UNUSED(int func))

{

    int infd = 0, outfd = -1, bufsize = SYSREAD_BUFSIZE, count;

    char *outvar = NULL, *countvar = NULL, *inbuf;

    /* -i: input file descriptor if not stdin */

    if (OPT_ISSET(ops, 'i')) {

	infd = getposint(OPT_ARG(ops, 'i'), nam);

	if (infd < 0)

	    return 1;

    }

    /* -o: output file descriptor, else store in REPLY */

    if (OPT_ISSET(ops, 'o')) {

	if (*args) {

	    zwarnnam(nam, "no argument allowed with -o", NULL, 0);

	    return 1;

	}

	outfd = getposint(OPT_ARG(ops, 'o'), nam);

	if (outfd < 0)

	    return 1;

    }

    /* -s: buffer size if not default SYSREAD_BUFSIZE */

    if (OPT_ISSET(ops, 's')) {

	bufsize = getposint(OPT_ARG(ops, 's'), nam);

	if (bufsize < 0)

	    return 1;

    }

    /* -c: name of variable to store count of transferred bytes */

    if (OPT_ISSET(ops, 'c')) {

	countvar = OPT_ARG(ops, 'c');

	if (!isident(countvar)) {

	    zwarnnam(nam, "not an identifier: %s", countvar, 0);

	    return 1;

	}

    }

    if (*args) {

	/*

	 * Variable in which to store result if doing a plain read.

	 * Default variable if not specified is REPLY.

	 * If writing, only stuff we couldn't write is stored here,

	 * no default in that case (we just discard it if no variable).

	 */

	outvar = *args;

	if (!isident(outvar)) {

	    zwarnnam(nam, "not an identifier: %s", outvar, 0);

	    return 1;

	}

    }

    inbuf = zhalloc(bufsize);

#if defined(HAVE_POLL) || defined(HAVE_SELECT)

    /* -t: timeout */

    if (OPT_ISSET(ops, 't'))

    {

# ifdef HAVE_POLL

	struct pollfd poll_fd;

	mnumber to_mn;

	int to_int, ret;

	poll_fd.fd = infd;

	poll_fd.events = POLLIN;

	to_mn = matheval(OPT_ARG(ops, 't'));

	if (errflag)

	    return 1;

	if (to_mn.type == MN_FLOAT)

	    to_int = (int) (1000 * to_mn.u.d);

	else

	    to_int = 1000 * (int)to_mn.u.l;

	while ((ret = poll(&poll_fd, 1, to_int)) < 0) {

	    if (errno != EINTR || errflag || retflag || breaks || contflag)

		break;

	}

	if (ret <= 0) {

	    /* treat non-timeout error as error on read */

	    return ret ? 2 : 4;

	}

# else

	/* using select */

	struct timeval select_tv;

	fd_set fds;

	mnumber to_mn;

	int ret;

	FD_ZERO(&fds);

	FD_SET(infd, &fds);

	to_mn = matheval(OPT_ARG(ops, 't'));

	if (errflag)

	    return 1;

	if (to_mn.type == MN_FLOAT) {

	    select_tv.tv_sec = (int) to_mn.u.d;

	    select_tv.tv_usec =

		(int) ((to_mn.u.d - select_tv.tv_sec) * 1e6);

	} else {

	    select_tv.tv_sec = (int) to_mn.u.l;

	    select_tv.tv_usec = 0;

	}

	while ((ret = select(infd+1, (SELECT_ARG_2_T) &fds, 

			     NULL, NULL,&select_tv)) < 1) {

	    if (errno != EINTR || errflag || retflag || breaks || contflag)

		break;

	}

	if (ret <= 0) {

	    /* treat non-timeout error as error on read */

	    return ret ? 2 : 4;

	}

# endif

    }

#endif

    while ((count = read(infd, inbuf, bufsize)) < 0) {

	if (errno != EINTR || errflag || retflag || breaks || contflag)

	    break;

    }

    if (countvar)

	setiparam(countvar, count);

    if (count < 0)

	return 2;

    if (outfd >= 0) {

	if (!count)

	    return 5;

	while (count > 0) {

	    int ret;

	    ret = write(outfd, inbuf, count);

	    if (ret < 0) {

		if (errno == EINTR && !errflag &&

		    !retflag && !breaks && !contflag)

		    continue;

		if (outvar)

		    setsparam(outvar, metafy(inbuf, count, META_DUP));

		if (countvar)

		    setiparam(countvar, count);

		return 3;

	    }

	    inbuf += ret;

	    count -= ret;

	}

	return 0;

    }

    if (!outvar)

	    outvar = "REPLY";

    /* do this even if we read zero bytes */

    setsparam(outvar, metafy(inbuf, count, META_DUP));

    return count ? 0 : 5;

}

/*

 * Return values of bin_syswrite:

 *	0	Successfully written

 *	1	Error in parameters to command

 *	2	Error on write, ERRNO set by system

 */

/**/

static int

bin_syswrite(char *nam, char **args, Options ops, UNUSED(int func))

{

    int outfd = 1, len, count, totcount;

    char *countvar = NULL;

    /* -o: output file descriptor if not stdout */

    if (OPT_ISSET(ops, 'o')) {

	outfd = getposint(OPT_ARG(ops, 'o'), nam);

	if (outfd < 0)

	    return 1;

    }

    /* -c: variable in which to store count of bytes written */

    if (OPT_ISSET(ops, 'c')) {

	countvar = OPT_ARG(ops, 'c');

	if (!isident(countvar)) {

	    zwarnnam(nam, "not an identifier: %s", countvar, 0);

	    return 1;

	}

    }

    totcount = 0;

    unmetafy(*args, &len);

    while (len) {

	while ((count = write(outfd, *args, len)) < 0) {

	    if (errno != EINTR || errflag || retflag || breaks || contflag)

	    {

		if (countvar)

		    setiparam(countvar, totcount);

		return 2;

	    }

	}

	*args += count;

	totcount += count;

	len -= count;

    }

    if (countvar)

	setiparam(countvar, totcount);

    return 0;

}

/*

 * Return values of bin_syserror:

 *	0	Successfully processed error

 *		(although if the number was invalid the string

 *		may not be useful)

 *	1	Error in parameters

 *	2	Name of error not recognised.

 */

/**/

static int

bin_syserror(char *nam, char **args, Options ops, UNUSED(int func))

{

    int num = 0;

    char *errvar = NULL, *msg, *pfx = "", *str;

    /* variable in which to write error message */

    if (OPT_ISSET(ops, 'e')) {

	errvar = OPT_ARG(ops, 'e');

	if (!isident(errvar)) {

	    zwarnnam(nam, "not an identifier: %s", errvar, 0);

	    return 1;

	}

    }

    /* prefix for error message */

    if (OPT_ISSET(ops, 'p'))

	pfx = OPT_ARG(ops, 'p');

    if (!*args)

	num = errno;

    else {

	char *ptr = *args;

	while (*ptr && idigit(*ptr))

	    ptr++;

	if (!*ptr && ptr > *args)

	    num = atoi(*args);

	else {

	    const char **eptr;

	    for (eptr = sys_errnames; *eptr; eptr++) {

		if (!strcmp(*eptr, *args)) {

		    num = (eptr - sys_errnames) + 1;

		    break;

		}

	    }

	    if (!*eptr)

		return 2;

	}

    }

    msg = strerror(num);

    if (errvar) {

	str = (char *)zalloc(strlen(msg) + strlen(pfx) + 1);

	sprintf(str, "%s%s", pfx, msg);

	setsparam(errvar, str);

    } else {

	fprintf(stderr, "%s%s\n", pfx, msg);

    }

    return 0;

}

/* Functions for the errnos special parameter. */

/**/

static char **

errnosgetfn(UNUSED(Param pm))

{

    /* arrdup etc. should really take const pointers as arguments */

    return arrdup((char **)sys_errnames);

}

static struct builtin bintab[] = {

    BUILTIN("syserror", 0, bin_syserror, 0, 1, 0, "e:p:", NULL),

    BUILTIN("sysread", 0, bin_sysread, 0, 1, 0, "c:i:o:s:t:", NULL),

    BUILTIN("syswrite", 0, bin_syswrite, 1, 1, 0, "c:o:", NULL),

};

static const struct gsu_array errnos_gsu =

{ errnosgetfn, arrsetfn, stdunsetfn };

/* The load/unload routines required by the zsh library interface */

/**/

int

setup_(UNUSED(Module m))

{

    return 0;

}

/**/

static void

tidyparam(Param pm)

{

    if (!pm)

	return;

    pm->flags &= ~PM_READONLY;

    unsetparam_pm(pm, 0, 1);

}

/**/

int

boot_(Module m)

{

    Param pm_nos;

    /* this takes care of an autoload on errnos */

    unsetparam("errnos");

    if (!(pm_nos = createparam("errnos", PM_ARRAY|PM_SPECIAL|PM_READONLY|

			       PM_HIDE|PM_HIDEVAL|PM_REMOVABLE)))

	return 1;

    pm_nos->gsu.a = &errnos_gsu;

    if (!addbuiltins(m->nam, bintab, sizeof(bintab)/sizeof(*bintab))) {

	tidyparam(pm_nos);

	return 1;

    }

    return 0;

}

/**/

int

cleanup_(Module m)

{

    tidyparam((Param)paramtab->getnode(paramtab, "errnos"));

    deletebuiltins(m->nam, bintab, sizeof(bintab)/sizeof(*bintab));

    return 0;

}

/**/

int

finish_(UNUSED(Module m))

{

    return 0;

}