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/****************************************************************************
* apps/system/cle/cle.c
*
* Copyright (C) 2014 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 <stdarg.h>
#include <stdint.h>
#include <stdbool.h>
#include <stdio.h>
#include <unistd.h>
#include <string.h>
#include <ctype.h>
#include <syslog.h>
#include <errno.h>
#include <debug.h>
#include <nuttx/ascii.h>
#include <nuttx/vt100.h>
#include "system/cle.h"
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/* Some environments may return CR as end-of-line, others LF, and others
* both. If not specified, the logic here assumes either (but not both) as
* the default.
*/
#if defined(CONFIG_EOL_IS_CR)
# undef CONFIG_EOL_IS_LF
# undef CONFIG_EOL_IS_BOTH_CRLF
# undef CONFIG_EOL_IS_EITHER_CRLF
#elif defined(CONFIG_EOL_IS_LF)
# undef CONFIG_EOL_IS_CR
# undef CONFIG_EOL_IS_BOTH_CRLF
# undef CONFIG_EOL_IS_EITHER_CRLF
#elif defined(CONFIG_EOL_IS_BOTH_CRLF)
# undef CONFIG_EOL_IS_CR
# undef CONFIG_EOL_IS_LF
# undef CONFIG_EOL_IS_EITHER_CRLF
#elif defined(CONFIG_EOL_IS_EITHER_CRLF)
# undef CONFIG_EOL_IS_CR
# undef CONFIG_EOL_IS_LF
# undef CONFIG_EOL_IS_BOTH_CRLF
#else
# undef CONFIG_EOL_IS_CR
# undef CONFIG_EOL_IS_LF
# undef CONFIG_EOL_IS_BOTH_CRLF
# define CONFIG_EOL_IS_EITHER_CRLF 1
#endif
/* Control characters */
#undef CTRL
#define CTRL(a) ((a) & 0x1f)
#define CLE_BEL(priv) cle_putch(priv,CTRL('G'))
/* Sizes of things */
#define TABSIZE 8 /* A TAB is eight characters */
#define TABMASK 7 /* Mask for TAB alignment */
#define NEXT_TAB(p) (((p) + TABSIZE) & ~TABMASK)
/* Debug */
#ifndef CONFIG_SYSTEM_CLE_DEBUGLEVEL
# define CONFIG_SYSTEM_CLE_DEBUGLEVEL 0
#endif
#ifdef CONFIG_CPP_HAVE_VARARGS
# if CONFIG_SYSTEM_CLE_DEBUGLEVEL > 0
# define cledbg(format, ...) \
syslog(LOG_DEBUG, EXTRA_FMT format EXTRA_ARG, ##__VA_ARGS__)
# else
# define cledbg(x...)
# endif
# if CONFIG_SYSTEM_CLE_DEBUGLEVEL > 1
# define cleinfo(format, ...) \
syslog(LOG_DEBUG, EXTRA_FMT format EXTRA_ARG, ##__VA_ARGS__)
# else
# define cleinfo(x...)
# endif
#else
# if CONFIG_SYSTEM_CLE_DEBUGLEVEL > 0
# define cledbg cle_debug
# else
# define cledbg (void)
# endif
# if CONFIG_SYSTEM_CLE_DEBUGLEVEL > 1
# define cleinfo cle_debug
# else
# define cleinfo (void)
# endif
#endif
/****************************************************************************
* Private Types
****************************************************************************/
/* VI Key Bindings */
enum cle_key_e
{
KEY_BEGINLINE = CTRL('A'), /* Move cursor to start of current line */
KEY_LEFT = CTRL('B'), /* Move left one character */
KEY_DEL = CTRL('D'), /* Delete a single character at the cursor position */
KEY_ENDLINE = CTRL('E'), /* Move cursor to end of current line */
KEY_RIGHT = CTRL('F'), /* Move right one character */
KEY_DELLEFT = CTRL('H'), /* Delete character, left (backspace) */
KEY_DELEOL = CTRL('K'), /* Delete to the end of the line */
KEY_DELLINE = CTRL('U'), /* Delete the entire line */
KEY_QUOTE = '\\', /* The next character is quote (use literal value) */
};
/* This structure describes the overall state of the editor */
struct cle_s
{
uint16_t curpos; /* Current cursor position */
uint16_t cursave; /* Saved cursor position */
uint16_t row; /* This is the row that we are editing in */
uint16_t coloffs; /* Left cursor offset */
uint16_t linelen; /* Size of the line buffer */
uint16_t nchars; /* Size of data in the line buffer */
int infd; /* Input file descriptor */
int outfd; /* Output file descriptor */
FAR char *line; /* Line buffer */
};
/****************************************************************************
* Private Function Prototypes
****************************************************************************/
#if !defined(CONFIG_CPP_HAVE_VARARGS) && CONFIG_SYSTEM_CLE_DEBUGLEVEL > 0
static int cle_debug(FAR const char *fmt, ...);
#endif
/* Low-level display and data entry functions */
static void cle_write(FAR struct cle_s *priv, FAR const char *buffer,
uint16_t buflen);
static void cle_putch(FAR struct cle_s *priv, char ch);
static int cle_getch(FAR struct cle_s *priv);
static void cle_cursoron(FAR struct cle_s *priv);
static void cle_cursoroff(FAR struct cle_s *priv);
static void cle_setcursor(FAR struct cle_s *priv, uint16_t column);
static int cle_getcursor(FAR struct cle_s *priv, uint16_t *prow,
uint16_t *pcolumn);
static void cle_clrtoeol(FAR struct cle_s *priv);
/* Editor function */
static bool cle_opentext(FAR struct cle_s *priv, uint16_t pos,
uint16_t increment);
static void cle_closetext(FAR struct cle_s *priv, uint16_t pos, uint16_t size);
static void cle_showtext(FAR struct cle_s *priv);
static void cle_insertch(FAR struct cle_s *priv, char ch);
static int cle_editloop(FAR struct cle_s *priv);
/****************************************************************************
* Private Data
****************************************************************************/
/* VT100 escape sequences */
static const char g_cursoron[] = VT100_CURSORON;
static const char g_cursoroff[] = VT100_CURSOROFF;
static const char g_getcursor[] = VT100_GETCURSOR;
static const char g_erasetoeol[] = VT100_CLEAREOL;
static const char g_fmtcursorpos[] = VT100_FMT_CURSORPOS;
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: cle_debug
*
* Description:
* Print a debug message to the syslog
*
****************************************************************************/
#if !defined(CONFIG_CPP_HAVE_VARARGS) && CONFIG_SYSTEM_CLE_DEBUGLEVEL > 0
static int cle_debug(FAR const char *fmt, ...)
{
va_list ap;
int ret;
/* Let vsyslog do the real work */
va_start(ap, fmt);
ret = vsyslog(LOG_DEBUG, fmt, ap);
va_end(ap);
return ret;
}
#endif
/****************************************************************************
* Name: cle_write
*
* Description:
* Write a sequence of bytes to the console output device.
*
****************************************************************************/
static void cle_write(FAR struct cle_s *priv, FAR const char *buffer,
uint16_t buflen)
{
ssize_t nwritten;
uint16_t nremaining = buflen;
//cleinfo("buffer=%p buflen=%d\n", buffer, (int)buflen);
/* Loop until all bytes have been successfully written (or until a
* unrecoverable error is encountered)
*/
do
{
/* Take the next gulp */
nwritten = write(priv->outfd, buffer, buflen);
/* Handle write errors. write() should neve return 0. */
if (nwritten <= 0)
{
/* EINTR is not really an error; it simply means that a signal was
* received while waiting for write.
*/
int errcode = errno;
if (nwritten == 0 || errcode != EINTR)
{
cledbg("ERROR: write to stdout failed: %d\n", errcode);
return;
}
}
/* Decrement the count of bytes remaining to be sent (to handle the
* case of a partial write)
*/
else
{
nremaining -= nwritten;
}
}
while (nremaining > 0);
}
/****************************************************************************
* Name: cle_putch
*
* Description:
* Write a single character to the console output device.
*
****************************************************************************/
static void cle_putch(FAR struct cle_s *priv, char ch)
{
cle_write(priv, &ch, 1);
}
/****************************************************************************
* Name: cle_getch
*
* Description:
* Get a single character from the console input device.
*
****************************************************************************/
static int cle_getch(FAR struct cle_s *priv)
{
char buffer;
ssize_t nread;
/* Loop until we successfully read a character (or until an unexpected
* error occurs).
*/
do
{
/* Read one character from the incoming stream */
nread = read(priv->infd, &buffer, 1);
/* Check for error or end-of-file. */
if (nread <= 0)
{
/* EINTR is not really an error; it simply means that a signal we
* received while waiting for input.
*/
int errcode = errno;
if (nread == 0 || errcode != EINTR)
{
cledbg("ERROR: read from stdin failed: %d\n", errcode);
return -EIO;
}
}
}
while (nread < 1);
/* On success, return the character that was read */
cleinfo("Returning: %c[%02x]\n", isprint(buffer) ? buffer : '.', buffer);
return buffer;
}
/****************************************************************************
* Name: cle_cursoron
*
* Description:
* Turn on the cursor
*
****************************************************************************/
static void cle_cursoron(FAR struct cle_s *priv)
{
/* Send the VT100 CURSORON command */
cle_write(priv, g_cursoron, sizeof(g_cursoron));
}
/****************************************************************************
* Name: cle_cursoroff
*
* Description:
* Turn off the cursor
*
****************************************************************************/
static void cle_cursoroff(FAR struct cle_s *priv)
{
/* Send the VT100 CURSOROFF command */
cle_write(priv, g_cursoroff, sizeof(g_cursoroff));
}
/****************************************************************************
* Name: cle_setcursor
*
* Description:
* Move the current cursor position to position (row,col)
*
****************************************************************************/
static void cle_setcursor(FAR struct cle_s *priv, uint16_t column)
{
char buffer[16];
int len;
cleinfo("row=%d column=%d offset=%d\n", priv->row, column, priv->coloffs);
/* Format the cursor position command. The origin is (1,1). */
len = snprintf(buffer, 16, g_fmtcursorpos, priv->row, column + priv->coloffs);
/* Send the VT100 CURSORPOS command */
cle_write(priv, buffer, len);
}
/****************************************************************************
* Name: cle_getcursor
*
* Description:
* Get the current cursor position.
*
****************************************************************************/
static int cle_getcursor(FAR struct cle_s *priv, FAR uint16_t *prow,
FAR uint16_t *pcolumn)
{
uint32_t row;
uint32_t column;
int nbad;
int ch;
/* Send the VT100 GETCURSOR command */
cle_write(priv, g_getcursor, sizeof(g_getcursor));
/* We expect to get ESC[v;hR where v is the row and h is the column */
nbad = 0;
for (;;)
{
/* Get the next character from the input */
ch = cle_getch(priv);
if (ch == ASCII_ESC)
{
break;
}
else if (ch < 0)
{
return -EIO;
}
else if (++nbad > 3)
{
/* We are probably talking to a non-VT100 terminal! */
return -EINVAL;
}
}
/* Have ESC, now we expect '[' */
nbad = 0;
for (;;)
{
/* Get the next character from the input */
ch = cle_getch(priv);
if (ch == '[')
{
break;
}
else if (ch < 0)
{
return -EIO;
}
else
{
/* We are probably talking to a non-VT100 terminal! */
return -EINVAL;
}
}
/* Have ESC'['. Now we expect to see a numeric value terminated with ';' */
row = 0;
for (;;)
{
/* Get the next character from the input */
ch = cle_getch(priv);
if (isdigit(ch))
{
row = 10*row + (ch - '0');
}
else if (ch == ';')
{
break;
}
else if (ch < 0)
{
return -EIO;
}
else
{
return -EINVAL;
}
}
/* Have ESC'['v';'. Now we expect to see another numeric value terminated with 'R' */
column = 0;
for (;;)
{
/* Get the next character from the input */
ch = cle_getch(priv);
if (isdigit(ch))
{
column = 10*column + (ch - '0');
}
else if (ch == 'R')
{
break;
}
else if (ch < 0)
{
return -EIO;
}
else
{
return -EINVAL;
}
}
cleinfo("row=%ld column=%ld\n", row, column);
/* Make sure that the values are within range */
if (row <= UINT16_MAX && column <= UINT16_MAX)
{
*prow = row;
*pcolumn = column;
return OK;
}
return -ERANGE;
}
/****************************************************************************
* Name: cle_clrtoeol
*
* Description:
* Clear the display from the current cursor position to the end of the
* current line.
*
****************************************************************************/
static void cle_clrtoeol(FAR struct cle_s *priv)
{
/* Send the VT100 ERASETOEOL command */
cle_write(priv, g_erasetoeol, sizeof(g_erasetoeol));
}
/****************************************************************************
* Name: cle_opentext
*
* Description:
* Make space for new text of size 'increment' at the specified cursor
* position. This function will not allow text grow beyond ('linelen' - 1)
* in size.
*
****************************************************************************/
static bool cle_opentext(FAR struct cle_s *priv, uint16_t pos,
uint16_t increment)
{
int i;
cleinfo("pos=%ld increment=%ld\n", (long)pos, (long)increment);
/* Check if there is space in the line buffer to open up a region the size
* of 'increment'
*/
if (priv->nchars + increment >= priv->linelen)
{
CLE_BEL(priv);
return false;
}
/* Move text to make space for new text of size 'increment' at the current
* cursor position
*/
for (i = priv->nchars - 1; i >= pos; i--)
{
priv->line[i + increment] = priv->line[i];
}
/* Adjust end of file position */
priv->nchars += increment;
return true;
}
/****************************************************************************
* Name: cle_closetext
*
* Description:
* Delete a region in the line buffer by copying the end of the line buffer
* over the deleted region and adjusting the size of the region.
*
****************************************************************************/
static void cle_closetext(FAR struct cle_s *priv, uint16_t pos, uint16_t size)
{
int i;
cleinfo("pos=%ld size=%ld\n", (long)pos, (long)size);
/* Close up the gap to remove 'size' characters at 'pos' */
for (i = pos + size; i < priv->nchars; i++)
{
priv->line[i - size] = priv->line[i];
}
/* Adjust sizes and positions */
priv->nchars -= size;
/* Check if the cursor position is beyond the deleted region */
if (priv->curpos > pos + size)
{
/* Yes... just subtract the size of the deleted region */
priv->curpos -= size;
}
/* What if the position is within the deleted region? Set it to the
* beginning of the deleted region.
*/
else if (priv->curpos > pos)
{
priv->curpos = pos;
}
}
/****************************************************************************
* Name: cle_showtext
*
* Description:
* Update the display based on the last operation. This function is
* called at the beginning of the editor loop.
*
****************************************************************************/
static void cle_showtext(FAR struct cle_s *priv)
{
uint16_t column;
uint16_t tabcol;
/* Turn off the cursor during the update. */
cle_cursoroff(priv);
/* Set the cursor position to the beginning of this row */
cle_setcursor(priv, 0);
cle_clrtoeol(priv);
/* Loop for each column */
for (column = 0; column < priv->nchars; )
{
/* Perform TAB expansion */
if (priv->line[column] == '\t')
{
tabcol = NEXT_TAB(column);
if (tabcol < priv->linelen)
{
for (; column < tabcol; column++)
{
cle_putch(priv, ' ');
}
}
else
{
/* Break out of the loop... there is nothing left on the
* line but whitespace.
*/
break;
}
}
/* Add the normal character to the display */
else
{
cle_putch(priv, priv->line[column]);
column++;
}
}
/* Turn the cursor back on */
cle_cursoron(priv);
}
/****************************************************************************
* Name: cle_insertch
*
* Description:
* Insert one character into the line buffer
*
****************************************************************************/
static void cle_insertch(FAR struct cle_s *priv, char ch)
{
cleinfo("curpos=%ld ch=%c[%02x]\n", priv->curpos, isprint(ch) ? ch : '.', ch);
/* Make space in the buffer for the new character */
if (cle_opentext(priv, priv->curpos, 1))
{
/* Add the new character to the buffer */
priv->line[priv->curpos++] = ch;
}
}
/****************************************************************************
* Name: cle_editloop
*
* Description:
* Command line editor loop
*
****************************************************************************/
static int cle_editloop(FAR struct cle_s *priv)
{
/* Loop while we are in command mode */
for (;;)
{
int ch;
/* Make sure that the display reflects the current state */
cle_showtext(priv);
cle_setcursor(priv, priv->curpos);
/* Get the next character from the input */
ch = cle_getch(priv);
if (ch < 0)
{
return -EIO;
}
/* Then handle the character. */
switch (ch)
{
case KEY_BEGINLINE: /* Move cursor to start of current line */
{
priv->curpos = 0;
}
break;
case KEY_LEFT: /* Move the cursor left 1 character */
{
if (priv->curpos > 0)
{
priv->curpos--;
}
else
{
CLE_BEL(priv);
}
}
break;
case KEY_DEL: /* Delete 1 character at the cursor */
case ASCII_DEL:
{
if (priv->curpos < priv->nchars)
{
cle_closetext(priv, priv->curpos, 1);
}
else
{
CLE_BEL(priv);
}
}
break;
case KEY_ENDLINE: /* Move cursor to end of current line */
{
priv->curpos = priv->nchars;
}
break;
case KEY_RIGHT: /* Move the cursor right one character */
{
if (priv->curpos < priv->nchars)
{
priv->curpos++;
}
else
{
CLE_BEL(priv);
}
}
break;
case KEY_DELLEFT: /* Delete 1 character before the cursor */
//case ASCII_BS:
{
if (priv->curpos > 0)
{
cle_closetext(priv, --priv->curpos, 1);
}
else
{
CLE_BEL(priv);
}
}
break;
case KEY_DELEOL: /* Delete to the end of the line */
{
priv->nchars = (priv->nchars > 0 ? priv->curpos + 1 : 0);
}
break;
case KEY_DELLINE: /* Delete to the end of the line */
{
priv->nchars = 0;
priv->curpos = 0;
}
break;
case KEY_QUOTE: /* Quoted character follows */
{
ch = cle_getch(priv);
if (ch < 0)
{
return -EIO;
}
/* Insert the next character unconditionally */
cle_insertch(priv, ch);
}
break;
/* Newline terminates editing. But what is a newline? */
#if defined(CONFIG_EOL_IS_CR) || defined(CONFIG_EOL_IS_EITHER_CRLF)
case '\r': /* CR terminates line */
#elif defined(CONFIG_EOL_IS_LF) || defined(CONFIG_EOL_IS_BOTH_CRLF) || \
defined(CONFIG_EOL_IS_EITHER_CRLF)
case '\n': /* LF terminates line */
#endif
{
/* Add the newline character to the buffer at the end of the line */
priv->curpos = priv->nchars;
cle_insertch(priv, '\n');
cle_putch(priv, '\n');
return OK;
}
break;
#if defined(CONFIG_EOL_IS_BOTH_CRLF)
case '\r': /* Wait for the LF */
break;
#endif
/* Text to insert or unimplemented/invalid keypresses */
default:
{
/* Ignore all control characters except for tab and newline */
if (!iscntrl(ch) || ch == '\t')
{
/* Insert the filtered character into the buffer */
cle_insertch(priv, ch);
}
else
{
CLE_BEL(priv);
}
}
break;
}
}
return OK;
}
/****************************************************************************
* Command line processing
****************************************************************************/
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: cle
*
* Description:
* EMACS-like command line editor. This is actually more like readline
* than is the NuttX readline!
*
****************************************************************************/
int cle(FAR char *line, uint16_t linelen, FILE *instream, FILE *outstream)
{
FAR struct cle_s priv;
uint16_t column;
int ret;
/* Initialize the CLE state structure */
memset(&priv, 0, sizeof(struct cle_s));
priv.linelen = linelen;
priv.line = line;
/* REVISIT: Non-standard, non-portable */
priv.infd = instream->fs_fd;
priv.outfd = outstream->fs_fd;
/* Get the current cursor position */
ret = cle_getcursor(&priv, &priv.row, &column);
if (ret < 0)
{
return ret;
}
/* Turn the column number into an offset */
if (column < 1)
{
return -EINVAL;
}
priv.coloffs = column - 1;
cleinfo("row=%d column=%d\n", priv.row, column);
/* The editor loop */
ret = cle_editloop(&priv);
/* Make sure that the line is NUL terminated */
line[priv.nchars] = '\0';
return ret;
}