/* input.c -- character input functions for readline. */

/* Copyright (C) 1994-2010 Free Software Foundation, Inc.

   This file is part of the GNU Readline Library (Readline), a library

   for reading lines of text with interactive input and history editing.      

   Readline 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 3 of the License, or

   (at your option) any later version.

   Readline 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 Readline.  If not, see <http://www.gnu.org/licenses/>.

*/

#define READLINE_LIBRARY

#if defined (__TANDEM)

#  include <floss.h>

#endif

#if defined (HAVE_CONFIG_H)

#  include <config.h>

#endif

#include <sys/types.h>

#include <fcntl.h>

#if defined (HAVE_SYS_FILE_H)

#  include <sys/file.h>

#endif /* HAVE_SYS_FILE_H */

#if defined (HAVE_UNISTD_H)

#  include <unistd.h>

#endif /* HAVE_UNISTD_H */

#if defined (HAVE_STDLIB_H)

#  include <stdlib.h>

#else

#  include "ansi_stdlib.h"

#endif /* HAVE_STDLIB_H */

#include "posixselect.h"

#if defined (FIONREAD_IN_SYS_IOCTL)

#  include <sys/ioctl.h>

#endif

#include <stdio.h>

#include <errno.h>

#if !defined (errno)

extern int errno;

#endif /* !errno */

/* System-specific feature definitions and include files. */

#include "rldefs.h"

#include "rlmbutil.h"

/* Some standard library routines. */

#include "readline.h"

#include "rlprivate.h"

#include "rlshell.h"

#include "xmalloc.h"

/* What kind of non-blocking I/O do we have? */

#if !defined (O_NDELAY) && defined (O_NONBLOCK)

#  define O_NDELAY O_NONBLOCK	/* Posix style */

#endif

/* Non-null means it is a pointer to a function to run while waiting for

   character input. */

rl_hook_func_t *rl_event_hook = (rl_hook_func_t *)NULL;

rl_getc_func_t *rl_getc_function = rl_getc;

static int _keyboard_input_timeout = 100000;		/* 0.1 seconds; it's in usec */

static int ibuffer_space PARAMS((void));

static int rl_get_char PARAMS((int *));

static int rl_gather_tyi PARAMS((void));

/* **************************************************************** */

/*								    */

/*			Character Input Buffering       	    */

/*								    */

/* **************************************************************** */

static int pop_index, push_index;

static unsigned char ibuffer[512];

static int ibuffer_len = sizeof (ibuffer) - 1;

#define any_typein (push_index != pop_index)

int

_rl_any_typein ()

{

  return any_typein;

}

/* Return the amount of space available in the buffer for stuffing

   characters. */

static int

ibuffer_space ()

{

  if (pop_index > push_index)

    return (pop_index - push_index - 1);

  else

    return (ibuffer_len - (push_index - pop_index));

}

/* Get a key from the buffer of characters to be read.

   Return the key in KEY.

   Result is KEY if there was a key, or 0 if there wasn't. */

static int

rl_get_char (key)

     int *key;

{

  if (push_index == pop_index)

    return (0);

  *key = ibuffer[pop_index++];

#if 0

  if (pop_index >= ibuffer_len)

#else

  if (pop_index > ibuffer_len)

#endif

    pop_index = 0;

  return (1);

}

/* Stuff KEY into the *front* of the input buffer.

   Returns non-zero if successful, zero if there is

   no space left in the buffer. */

int

_rl_unget_char (key)

     int key;

{

  if (ibuffer_space ())

    {

      pop_index--;

      if (pop_index < 0)

	pop_index = ibuffer_len;

      ibuffer[pop_index] = key;

      return (1);

    }

  return (0);

}

int

_rl_pushed_input_available ()

{

  return (push_index != pop_index);

}

/* If a character is available to be read, then read it and stuff it into

   IBUFFER.  Otherwise, just return.  Returns number of characters read

   (0 if none available) and -1 on error (EIO). */

static int

rl_gather_tyi ()

{

  int tty;

  register int tem, result;

  int chars_avail, k;

  char input;

#if defined(HAVE_SELECT)

  fd_set readfds, exceptfds;

  struct timeval timeout;

#endif

  chars_avail = 0;

  tty = fileno (rl_instream);

#if defined (HAVE_SELECT)

  FD_ZERO (&readfds);

  FD_ZERO (&exceptfds);

  FD_SET (tty, &readfds);

  FD_SET (tty, &exceptfds);

  USEC_TO_TIMEVAL (_keyboard_input_timeout, timeout);

  result = select (tty + 1, &readfds, (fd_set *)NULL, &exceptfds, &timeout);

  if (result <= 0)

    return 0;	/* Nothing to read. */

#endif

  result = -1;

#if defined (FIONREAD)

  errno = 0;

  result = ioctl (tty, FIONREAD, &chars_avail);

  if (result == -1 && errno == EIO)

    return -1;

#endif

#if defined (O_NDELAY)

  if (result == -1)

    {

      tem = fcntl (tty, F_GETFL, 0);

      fcntl (tty, F_SETFL, (tem | O_NDELAY));

      chars_avail = read (tty, &input, 1);

      fcntl (tty, F_SETFL, tem);

      if (chars_avail == -1 && errno == EAGAIN)

	return 0;

      if (chars_avail == 0)	/* EOF */

	{

	  rl_stuff_char (EOF);

	  return (0);

	}

    }

#endif /* O_NDELAY */

#if defined (__MINGW32__)

  /* Use getch/_kbhit to check for available console input, in the same way

     that we read it normally. */

   chars_avail = isatty (tty) ? _kbhit () : 0;

   result = 0;

#endif

  /* If there's nothing available, don't waste time trying to read

     something. */

  if (chars_avail <= 0)

    return 0;

  tem = ibuffer_space ();

  if (chars_avail > tem)

    chars_avail = tem;

  /* One cannot read all of the available input.  I can only read a single

     character at a time, or else programs which require input can be

     thwarted.  If the buffer is larger than one character, I lose.

     Damn! */

  if (tem < ibuffer_len)

    chars_avail = 0;

  if (result != -1)

    {

      while (chars_avail--)

	{

	  RL_CHECK_SIGNALS ();

	  k = (*rl_getc_function) (rl_instream);

	  if (rl_stuff_char (k) == 0)

	    break;			/* some problem; no more room */

	  if (k == NEWLINE || k == RETURN)

	    break;

	}

    }

  else

    {

      if (chars_avail)

	rl_stuff_char (input);

    }

  return 1;

}

int

rl_set_keyboard_input_timeout (u)

     int u;

{

  int o;

  o = _keyboard_input_timeout;

  if (u >= 0)

    _keyboard_input_timeout = u;

  return (o);

}

/* Is there input available to be read on the readline input file

   descriptor?  Only works if the system has select(2) or FIONREAD.

   Uses the value of _keyboard_input_timeout as the timeout; if another

   readline function wants to specify a timeout and not leave it up to

   the user, it should use _rl_input_queued(timeout_value_in_microseconds)

   instead. */

int

_rl_input_available ()

{

#if defined(HAVE_SELECT)

  fd_set readfds, exceptfds;

  struct timeval timeout;

#endif

#if !defined (HAVE_SELECT) && defined(FIONREAD)

  int chars_avail;

#endif

  int tty;

  tty = fileno (rl_instream);

#if defined (HAVE_SELECT)

  FD_ZERO (&readfds);

  FD_ZERO (&exceptfds);

  FD_SET (tty, &readfds);

  FD_SET (tty, &exceptfds);

  timeout.tv_sec = 0;

  timeout.tv_usec = _keyboard_input_timeout;

  return (select (tty + 1, &readfds, (fd_set *)NULL, &exceptfds, &timeout) > 0);

#else

#if defined (FIONREAD)

  if (ioctl (tty, FIONREAD, &chars_avail) == 0)

    return (chars_avail);

#endif

#endif

#if defined (__MINGW32__)

  if (isatty (tty))

    return (_kbhit ());

#endif

  return 0;

}

int

_rl_input_queued (t)

     int t;

{

  int old_timeout, r;

  old_timeout = rl_set_keyboard_input_timeout (t);

  r = _rl_input_available ();

  rl_set_keyboard_input_timeout (old_timeout);

  return r;

}

void

_rl_insert_typein (c)

     int c;     

{    	

  int key, t, i;

  char *string;

  i = key = 0;

  string = (char *)xmalloc (ibuffer_len + 1);

  string[i++] = (char) c;

  while ((t = rl_get_char (&key)) &&

	 _rl_keymap[key].type == ISFUNC &&

	 _rl_keymap[key].function == rl_insert)

    string[i++] = key;

  if (t)

    _rl_unget_char (key);

  string[i] = '\0';

  rl_insert_text (string);

  xfree (string);

}

/* Add KEY to the buffer of characters to be read.  Returns 1 if the

   character was stuffed correctly; 0 otherwise. */

int

rl_stuff_char (key)

     int key;

{

  if (ibuffer_space () == 0)

    return 0;

  if (key == EOF)

    {

      key = NEWLINE;

      rl_pending_input = EOF;

      RL_SETSTATE (RL_STATE_INPUTPENDING);

    }

  ibuffer[push_index++] = key;

#if 0

  if (push_index >= ibuffer_len)

#else

  if (push_index > ibuffer_len)

#endif

    push_index = 0;

  return 1;

}

/* Make C be the next command to be executed. */

int

rl_execute_next (c)

     int c;

{

  rl_pending_input = c;

  RL_SETSTATE (RL_STATE_INPUTPENDING);

  return 0;

}

/* Clear any pending input pushed with rl_execute_next() */

int

rl_clear_pending_input ()

{

  rl_pending_input = 0;

  RL_UNSETSTATE (RL_STATE_INPUTPENDING);

  return 0;

}

/* **************************************************************** */

/*								    */

/*			     Character Input			    */

/*								    */

/* **************************************************************** */

/* Read a key, including pending input. */

int

rl_read_key ()

{

  int c;

  rl_key_sequence_length++;

  if (rl_pending_input)

    {

      c = rl_pending_input;

      rl_clear_pending_input ();

    }

  else

    {

      /* If input is coming from a macro, then use that. */

      if (c = _rl_next_macro_key ())

	return (c);

      /* If the user has an event function, then call it periodically. */

      if (rl_event_hook)

	{

	  while (rl_event_hook)

	    {

	      if (rl_gather_tyi () < 0)	/* XXX - EIO */

		{

		  rl_done = 1;

		  return ('\n');

		}

	      RL_CHECK_SIGNALS ();

	      if (rl_get_char (&c) != 0)

		break;

	      if (rl_done)		/* XXX - experimental */

		return ('\n');

	      (*rl_event_hook) ();

	    }

	}

      else

	{

	  if (rl_get_char (&c) == 0)

	    c = (*rl_getc_function) (rl_instream);

	  RL_CHECK_SIGNALS ();

	}

    }

  return (c);

}

int

rl_getc (stream)

     FILE *stream;

{

  int result;

  unsigned char c;

  while (1)

    {

      RL_CHECK_SIGNALS ();

#if defined (__MINGW32__)

      if (isatty (fileno (stream)))

	return (getch ());

#endif

      result = read (fileno (stream), &c, sizeof (unsigned char));

      if (result == sizeof (unsigned char))

	return (c);

      /* If zero characters are returned, then the file that we are

	 reading from is empty!  Return EOF in that case. */

      if (result == 0)

	return (EOF);

#if defined (__BEOS__)

      if (errno == EINTR)

	continue;

#endif

#if defined (EWOULDBLOCK)

#  define X_EWOULDBLOCK EWOULDBLOCK

#else

#  define X_EWOULDBLOCK -99

#endif

#if defined (EAGAIN)

#  define X_EAGAIN EAGAIN

#else

#  define X_EAGAIN -99

#endif

      if (errno == X_EWOULDBLOCK || errno == X_EAGAIN)

	{

	  if (sh_unset_nodelay_mode (fileno (stream)) < 0)

	    return (EOF);

	  continue;

	}

#undef X_EWOULDBLOCK

#undef X_EAGAIN

      /* If the error that we received was SIGINT, then try again,

	 this is simply an interrupted system call to read ().

	 Otherwise, some error ocurred, also signifying EOF. */

      if (errno != EINTR)

	return (RL_ISSTATE (RL_STATE_READCMD) ? READERR : EOF);

    }

}

#if defined (HANDLE_MULTIBYTE)

/* read multibyte char */

int

_rl_read_mbchar (mbchar, size)

     char *mbchar;

     int size;

{

  int mb_len, c;

  size_t mbchar_bytes_length;

  wchar_t wc;

  mbstate_t ps, ps_back;

  memset(&ps, 0, sizeof (mbstate_t));

  memset(&ps_back, 0, sizeof (mbstate_t));

  mb_len = 0;  

  while (mb_len < size)

    {

      RL_SETSTATE(RL_STATE_MOREINPUT);

      c = rl_read_key ();

      RL_UNSETSTATE(RL_STATE_MOREINPUT);

      if (c < 0)

	break;

      mbchar[mb_len++] = c;

      mbchar_bytes_length = mbrtowc (&wc, mbchar, mb_len, &ps);

      if (mbchar_bytes_length == (size_t)(-1))

	break;		/* invalid byte sequence for the current locale */

      else if (mbchar_bytes_length == (size_t)(-2))

	{

	  /* shorted bytes */

	  ps = ps_back;

	  continue;

	} 

      else if (mbchar_bytes_length == 0)

	{

	  mbchar[0] = '\0';	/* null wide character */

	  mb_len = 1;

	  break;

	}

      else if (mbchar_bytes_length > (size_t)(0))

	break;

    }

  return mb_len;

}

/* Read a multibyte-character string whose first character is FIRST into

   the buffer MB of length MLEN.  Returns the last character read, which

   may be FIRST.  Used by the search functions, among others.  Very similar

   to _rl_read_mbchar. */

int

_rl_read_mbstring (first, mb, mlen)

     int first;

     char *mb;

     int mlen;

{

  int i, c;

  mbstate_t ps;

  c = first;

  memset (mb, 0, mlen);

  for (i = 0; c >= 0 && i < mlen; i++)

    {

      mb[i] = (char)c;

      memset (&ps, 0, sizeof (mbstate_t));

      if (_rl_get_char_len (mb, &ps) == -2)

	{

	  /* Read more for multibyte character */

	  RL_SETSTATE (RL_STATE_MOREINPUT);

	  c = rl_read_key ();

	  RL_UNSETSTATE (RL_STATE_MOREINPUT);

	}

      else

	break;

    }

  return c;

}

#endif /* HANDLE_MULTIBYTE */