289 lines
9.1 KiB
C
289 lines
9.1 KiB
C
/****************************************************************************
|
|
* apps/system/readline/readline_common.c
|
|
*
|
|
* Copyright (C) 2007-2008, 2011-2013 Gregory Nutt. All rights reserved.
|
|
* Author: Gregory Nutt <gnutt@nuttx.org>
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
*
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in
|
|
* the documentation and/or other materials provided with the
|
|
* distribution.
|
|
* 3. Neither the name NuttX nor the names of its contributors may be
|
|
* used to endorse or promote products derived from this software
|
|
* without specific prior written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
|
|
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
|
|
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
|
|
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
|
|
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
|
|
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
|
|
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
|
|
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
|
|
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
|
|
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
|
|
* POSSIBILITY OF SUCH DAMAGE.
|
|
*
|
|
****************************************************************************/
|
|
|
|
/****************************************************************************
|
|
* Included Files
|
|
****************************************************************************/
|
|
|
|
#include <nuttx/config.h>
|
|
|
|
#include <stdbool.h>
|
|
#include <string.h>
|
|
#include <ctype.h>
|
|
#include <errno.h>
|
|
#include <assert.h>
|
|
#include <debug.h>
|
|
|
|
#include <nuttx/ascii.h>
|
|
#include <nuttx/vt100.h>
|
|
|
|
#include <apps/readline.h>
|
|
#include "readline.h"
|
|
|
|
/****************************************************************************
|
|
* Pre-processor Definitions
|
|
****************************************************************************/
|
|
|
|
/****************************************************************************
|
|
* Private Type Declarations
|
|
****************************************************************************/
|
|
|
|
/****************************************************************************
|
|
* Private Function Prototypes
|
|
****************************************************************************/
|
|
|
|
/****************************************************************************
|
|
* Public Data
|
|
****************************************************************************/
|
|
|
|
/****************************************************************************
|
|
* Private Data
|
|
****************************************************************************/
|
|
/* <esc>[K is the VT100 command erases to the end of the line. */
|
|
|
|
static const char g_erasetoeol[] = VT100_CLEAREOL;
|
|
|
|
/****************************************************************************
|
|
* Private Functions
|
|
****************************************************************************/
|
|
|
|
/****************************************************************************
|
|
* Public Functions
|
|
****************************************************************************/
|
|
|
|
/****************************************************************************
|
|
* Name: readline_common
|
|
*
|
|
* readline() reads in at most one less than 'buflen' characters from
|
|
* 'instream' and stores them into the buffer pointed to by 'buf'.
|
|
* Characters are echoed on 'outstream'. Reading stops after an EOF or a
|
|
* newline. If a newline is read, it is stored into the buffer. A null
|
|
* terminator is stored after the last character in the buffer.
|
|
*
|
|
* This version of realine assumes that we are reading and writing to
|
|
* a VT100 console. This will not work well if 'instream' or 'outstream'
|
|
* corresponds to a raw byte steam.
|
|
*
|
|
* This function is inspired by the GNU readline but is an entirely
|
|
* different creature.
|
|
*
|
|
* Input Parameters:
|
|
* buf - The user allocated buffer to be filled.
|
|
* buflen - the size of the buffer.
|
|
* instream - The stream to read characters from
|
|
* outstream - The stream to each characters to.
|
|
*
|
|
* Returned values:
|
|
* On success, the (positive) number of bytes transferred is returned.
|
|
* EOF is returned to indicate either an end of file condition or a
|
|
* failure.
|
|
*
|
|
**************************************************************************/
|
|
|
|
ssize_t readline_common(FAR struct rl_common_s *vtbl, FAR char *buf, int buflen)
|
|
{
|
|
int escape;
|
|
int nch;
|
|
|
|
/* Sanity checks */
|
|
|
|
DEBUGASSERT(buf && buflen > 0);
|
|
|
|
if (buflen < 2)
|
|
{
|
|
*buf = '\0';
|
|
return 0;
|
|
}
|
|
|
|
/* <esc>[K is the VT100 command that erases to the end of the line. */
|
|
|
|
#ifdef CONFIG_READLINE_ECHO
|
|
RL_WRITE(vtbl, g_erasetoeol, sizeof(g_erasetoeol));
|
|
#endif
|
|
|
|
/* Read characters until we have a full line. On each the loop we must
|
|
* be assured that there are two free bytes in the line buffer: One for
|
|
* the next character and one for the null terminator.
|
|
*/
|
|
|
|
escape = 0;
|
|
nch = 0;
|
|
|
|
for(;;)
|
|
{
|
|
/* Get the next character. readline_rawgetc() returns EOF on any
|
|
* errors or at the end of file.
|
|
*/
|
|
|
|
int ch = RL_GETC(vtbl);
|
|
|
|
/* Check for end-of-file or read error */
|
|
|
|
if (ch == EOF)
|
|
{
|
|
/* Did we already received some data? */
|
|
|
|
if (nch > 0)
|
|
{
|
|
/* Yes.. Terminate the line (which might be zero length)
|
|
* and return the data that was received. The end-of-file
|
|
* or error condition will be reported next time.
|
|
*/
|
|
|
|
buf[nch] = '\0';
|
|
return nch;
|
|
}
|
|
|
|
return EOF;
|
|
}
|
|
|
|
/* Are we processing a VT100 escape sequence */
|
|
|
|
else if (escape)
|
|
{
|
|
/* Yes, is it an <esc>[, 3 byte sequence */
|
|
|
|
if (ch != ASCII_LBRACKET || escape == 2)
|
|
{
|
|
/* We are finished with the escape sequence */
|
|
|
|
escape = 0;
|
|
ch = 'a';
|
|
}
|
|
else
|
|
{
|
|
/* The next character is the end of a 3-byte sequence.
|
|
* NOTE: Some of the <esc>[ sequences are longer than
|
|
* 3-bytes, but I have not encountered any in normal use
|
|
* yet and, so, have not provided the decoding logic.
|
|
*/
|
|
|
|
escape = 2;
|
|
}
|
|
}
|
|
|
|
/* Check for backspace
|
|
*
|
|
* There are several notions of backspace, for an elaborate summary see
|
|
* http://www.ibb.net/~anne/keyboard.html. There is no clean solution.
|
|
* Here both DEL and backspace are treated like backspace here. The
|
|
* Unix/Linux screen terminal by default outputs DEL (0x7f) when the
|
|
* backspace key is pressed.
|
|
*/
|
|
|
|
else if (ch == ASCII_BS || ch == ASCII_DEL)
|
|
{
|
|
/* Eliminate that last character in the buffer. */
|
|
|
|
if (nch > 0)
|
|
{
|
|
nch--;
|
|
|
|
#ifdef CONFIG_READLINE_ECHO
|
|
/* Echo the backspace character on the console. Always output
|
|
* the backspace character because the VT100 terminal doesn't
|
|
* understand DEL properly.
|
|
*/
|
|
|
|
RL_PUTC(vtbl, ASCII_BS);
|
|
RL_WRITE(vtbl, g_erasetoeol, sizeof(g_erasetoeol));
|
|
#endif
|
|
}
|
|
}
|
|
|
|
/* Check for the beginning of a VT100 escape sequence */
|
|
|
|
else if (ch == ASCII_ESC)
|
|
{
|
|
/* The next character is escaped */
|
|
|
|
escape = 1;
|
|
}
|
|
|
|
/* Check for end-of-line. This is tricky only in that some
|
|
* environments may return CR as end-of-line, others LF, and
|
|
* others both.
|
|
*/
|
|
|
|
#if defined(CONFIG_EOL_IS_LF) || defined(CONFIG_EOL_IS_BOTH_CRLF)
|
|
else if (ch == '\n')
|
|
#elif defined(CONFIG_EOL_IS_CR)
|
|
else if (ch == '\r')
|
|
#elif CONFIG_EOL_IS_EITHER_CRLF
|
|
else if (ch == '\n' || ch == '\r')
|
|
#endif
|
|
{
|
|
/* The newline is stored in the buffer along with the null
|
|
* terminator.
|
|
*/
|
|
|
|
buf[nch++] = '\n';
|
|
buf[nch] = '\0';
|
|
|
|
#ifdef CONFIG_READLINE_ECHO
|
|
/* Echo the newline to the console */
|
|
|
|
RL_PUTC(vtbl, '\n');
|
|
#endif
|
|
return nch;
|
|
}
|
|
|
|
/* Otherwise, check if the character is printable and, if so, put the
|
|
* character in the line buffer
|
|
*/
|
|
|
|
else if (isprint(ch))
|
|
{
|
|
buf[nch++] = ch;
|
|
|
|
#ifdef CONFIG_READLINE_ECHO
|
|
/* Echo the character to the console */
|
|
|
|
RL_PUTC(vtbl, ch);
|
|
#endif
|
|
/* Check if there is room for another character and the line's
|
|
* null terminator. If not then we have to end the line now.
|
|
*/
|
|
|
|
if (nch + 1 >= buflen)
|
|
{
|
|
buf[nch] = '\0';
|
|
return nch;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|