binutils-gdb/readline/input.c

410 lines
8.8 KiB
C

/* input.c -- character input functions for readline. */
/* Copyright (C) 1994 Free Software Foundation, Inc.
This file is part of the GNU Readline Library, a library for
reading lines of text with interactive input and history editing.
The GNU Readline Library 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.
The GNU Readline Library 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.
The GNU General Public License is often shipped with GNU software, and
is generally kept in a file called COPYING or LICENSE. If you do not
have a copy of the license, write to the Free Software Foundation,
59 Temple Place, Suite 330, Boston, MA 02111 USA. */
#define READLINE_LIBRARY
#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 */
#if defined (HAVE_SELECT)
# if !defined (HAVE_SYS_SELECT_H) || !defined (M_UNIX)
# include <sys/time.h>
# endif
#endif /* HAVE_SELECT */
#if defined (HAVE_SYS_SELECT_H)
# include <sys/select.h>
#endif
#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"
/* 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. */
Function *rl_event_hook = (Function *)NULL;
Function *rl_getc_function = rl_getc;
/* **************************************************************** */
/* */
/* 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 (pop_index >= ibuffer_len)
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. */
static int
rl_unget_char (key)
int key;
{
if (ibuffer_space ())
{
pop_index--;
if (pop_index < 0)
pop_index = ibuffer_len - 1;
ibuffer[pop_index] = key;
return (1);
}
return (0);
}
/* If a character is available to be read, then read it
and stuff it into IBUFFER. Otherwise, just return. */
static void
rl_gather_tyi ()
{
int tty;
register int tem, result;
int chars_avail;
char input;
#if defined(HAVE_SELECT)
fd_set readfds, exceptfds;
struct timeval timeout;
#endif
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 = 100000; /* 0.1 seconds */
if (select (tty + 1, &readfds, (fd_set *)NULL, &exceptfds, &timeout) <= 0)
return; /* Nothing to read. */
#endif
result = -1;
#if defined (FIONREAD)
result = ioctl (tty, FIONREAD, &chars_avail);
#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;
}
#endif /* O_NDELAY */
/* If there's nothing available, don't waste time trying to read
something. */
if (chars_avail <= 0)
return;
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_stuff_char ((*rl_getc_function) (rl_instream));
}
else
{
if (chars_avail)
rl_stuff_char (input);
}
}
/* Is there input available to be read on the readline input file
descriptor? Only works if the system has select(2) or FIONREAD. */
int
_rl_input_available ()
{
#if defined(HAVE_SELECT)
fd_set readfds, exceptfds;
struct timeval timeout;
#endif
#if 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 = 100000; /* 0.1 seconds */
return (select (tty + 1, &readfds, (fd_set *)NULL, &exceptfds, &timeout) > 0);
#endif
#if defined (FIONREAD)
if (ioctl (tty, FIONREAD, &chars_avail) == 0)
return (chars_avail);
#endif
return 0;
}
void
_rl_insert_typein (c)
int c;
{
int key, t, i;
char *string;
i = key = 0;
string = 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);
free (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;
}
ibuffer[push_index++] = key;
if (push_index >= ibuffer_len)
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;
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_pending_input = 0;
}
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 && rl_get_char (&c) == 0)
{
(*rl_event_hook) ();
rl_gather_tyi ();
}
}
else
{
if (rl_get_char (&c) == 0)
c = (*rl_getc_function) (rl_instream);
}
}
return (c);
}
int
rl_getc (stream)
FILE *stream;
{
int result;
unsigned char c;
while (1)
{
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 (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 (EOF);
}
}