usr/dash/hetio.c - pub/scm/linux/kernel/git/bwh/klibc - Git at Google

 /*
  * Termios command line History and Editting for NetBSD sh (ash)
  * Copyright (c) 1999
  *	Main code:	Adam Rogoyski <rogoyski@cs.utexas.edu>
  *	Etc:		Dave Cinege <dcinege@psychosis.com>
  *
  * You may use this code as you wish, so long as the original author(s)
  * are attributed in any redistributions of the source code.
  * This code is 'as is' with no warranty.
  * This code may safely be consumed by a BSD or GPL license.
  *
  * v 0.5  19990328	Initial release
  *
  * Future plans: Simple file and path name completion. (like BASH)
  *
  */

 /*
 Usage and Known bugs:
 	Terminal key codes are not extensive, and more will probably
 	need to be added. This version was created on Debian GNU/Linux 2.x.
 	Delete, Backspace, Home, End, and the arrow keys were tested
 	to work in an Xterm and console. Ctrl-A also works as Home.
 	Ctrl-E also works as End. Ctrl-D and Ctrl-U perform their respective
 	functions. The binary size increase is <3K.

 	Editting will not display correctly for lines greater then the
 	terminal width. (more then one line.) However, history will.
 */

 #include <stdio.h>
 #include <unistd.h>
 #include <stdlib.h>
 #include <string.h>
 #include <termios.h>
 #include <ctype.h>
 #include <sys/ioctl.h>

 #include "input.h"
 #include "output.h"

 #include "hetio.h"


 #define  MAX_HISTORY   15			/* Maximum length of the linked list for the command line history */

 #define ESC	27
 #define DEL	127

 static struct history *his_front = NULL;	/* First element in command line list */
 static struct history *his_end = NULL;		/* Last element in command line list */
 static struct termios old_term, new_term;	/* Current termio and the previous termio before starting ash */

 static int history_counter = 0;			/* Number of commands in history list */
 static int reset_term = 0;			/* Set to true if the terminal needs to be reset upon exit */
 static int hetio_inter = 0;

 struct history
 {
    char *s;
    struct history *p;
    struct history *n;
 };


 void input_delete    (int);
 void input_home      (int *);
 void input_end       (int *, int);
 void input_backspace (int *, int *);


 void hetio_init(void)
 {
 	hetio_inter = 1;
 }


 void hetio_reset_term(void)
 {
 	if (reset_term)
 		tcsetattr(1, TCSANOW, &old_term);
 }


 void setIO(struct termios *new, struct termios *old)	/* Set terminal IO to canonical mode, and save old term settings. */
 {
 	tcgetattr(0, old);
 	memcpy(new, old, sizeof(*new));
 	new->c_cc[VMIN] = 1;
 	new->c_cc[VTIME] = 0;
 	new->c_lflag &= ~ICANON; /* unbuffered input */
 	new->c_lflag &= ~ECHO;
 	tcsetattr(0, TCSANOW, new);
 }

 void input_home(int *cursor)				/* Command line input routines */
 {
  	while (*cursor > 0) {
 		out1c('\b');
 		--*cursor;
 	}
 	flushout(out1);
 }


 void input_delete(int cursor)
 {
 	int j = 0;

 	memmove(parsenextc + cursor, parsenextc + cursor + 1,
 		BUFSIZ - cursor - 1);
 	for (j = cursor; j < (BUFSIZ - 1); j++) {
 		if (!*(parsenextc + j))
 			break;
 		else
 			out1c(*(parsenextc + j));
 	}

 	out1str(" \b");

 	while (j-- > cursor)
 		out1c('\b');
 	flushout(out1);
 }


 void input_end(int *cursor, int len)
 {
 	while (*cursor < len) {
 		out1str("\033[C");
 		++*cursor;
 	}
 	flushout(out1);
 }


 void
 input_backspace(int *cursor, int *len)
 {
 	int j = 0;

 	if (*cursor > 0) {
 		out1str("\b \b");
 		--*cursor;
 		memmove(parsenextc + *cursor, parsenextc + *cursor + 1,
 			BUFSIZ - *cursor + 1);

 		for (j = *cursor; j < (BUFSIZ - 1); j++) {
 			if (!*(parsenextc + j))
 				break;
 			else
 				out1c(*(parsenextc + j));
 		}

 		out1str(" \b");

 		while (j-- > *cursor)
 			out1c('\b');

 		--*len;
 		flushout(out1);
 	}
 }

 int hetio_read_input(int fd)
 {
 	int nr = 0;

 	/* Are we an interactive shell? */
 	if (!hetio_inter || fd) {
 		return -255;
 	} else {
 		int len = 0;
 		int j = 0;
 		int cursor = 0;
 		int break_out = 0;
 		int ret = 0;
 		char c = 0;
 		struct history *hp = his_end;

 		if (!reset_term) {
 			setIO(&new_term, &old_term);
 			reset_term = 1;
 		} else {
 			tcsetattr(0, TCSANOW, &new_term);
 		}

 		memset(parsenextc, 0, BUFSIZ);

 		while (1) {
 			if ((ret = read(fd, &c, 1)) < 1)
 				return ret;

 			switch (c) {
    				case 1:		/* Control-A Beginning of line */
    					input_home(&cursor);
 					break;
 				case 5:		/* Control-E EOL */
 					input_end(&cursor, len);
 					break;
 				case 4:		/* Control-D */
 					if (!len)
 						exitshell(0);
 					break;
 				case 21: 	/* Control-U */
 					/* Return to begining of line. */
 					for (; cursor > 0; cursor--)
 						out1c('\b');
 					/* Erase old command. */
 					for (j = 0; j < len; j++) {
 						/*
 						 * Clear buffer while we're at
 						 * it.
 						 */
 						parsenextc[j] = 0;
 						out1c(' ');
 					}
 					/* return to begining of line */
 					for (; len > 0; len--)
 						out1c('\b');
 					flushout(out1);
 					break;
 				case '\b':	/* Backspace */
 				case DEL:
 					input_backspace(&cursor, &len);
 					break;
 				case '\n':	/* Enter */
 					*(parsenextc + len++ + 1) = c;
 					out1c(c);
 					flushout(out1);
 					break_out = 1;
 					break;
 				case ESC:	/* escape sequence follows */
 					if ((ret = read(fd, &c, 1)) < 1)
 						return ret;

 					if (c == '[' ) {    /* 91 */
 						if ((ret = read(fd, &c, 1)) < 1)
 							return ret;

 						switch (c) {
 							case 'A':
 								if (hp && hp->p) {		/* Up */
 									hp = hp->p;
 									goto hop;
 								}
 								break;
 							case 'B':
 								if (hp && hp->n && hp->n->s) {	/* Down */
 									hp = hp->n;
 									goto hop;
 								}
 								break;

 hop:						/* hop */
 								len = strlen(parsenextc);

 								for (; cursor > 0; cursor--)		/* return to begining of line */
 									out1c('\b');

 		   						for (j = 0; j < len; j++)		/* erase old command */
 									out1c(' ');

 								for (; j > 0; j--)		/* return to begining of line */
 									out1c('\b');

 								strcpy (parsenextc, hp->s);		/* write new command */
 								len = strlen (hp->s);
 								out1str(parsenextc);
 								flushout(out1);
 								cursor = len;
 								break;
 							case 'C':		/* Right */
 								if (cursor < len) {
 									out1str("\033[C");
 									cursor++;
 									flushout(out1);
 						 		}
 								break;
 							case 'D':		/* Left */
 								if (cursor > 0) {
 									out1str("\033[D");
 									cursor--;
 									flushout(out1);
 								}
 								break;
 							case '3':		/* Delete */
 								if (cursor != len) {
 									input_delete(cursor);
 									len--;
 								}
 								break;
 							case '1':		/* Home (Ctrl-A) */
 								input_home(&cursor);
 								break;
 							case '4':		/* End (Ctrl-E) */
 								input_end(&cursor, len);
 								break;
 						}
 						if (c == '1' || c == '3' || c == '4')
 							if ((ret = read(fd, &c, 1)) < 1)
 								return ret;  /* read 126 (~) */
 					}

 					if (c == 'O') {	/* 79 */
 						if ((ret = read(fd, &c, 1)) < 1)
 							return ret;
 						switch (c) {
 							case 'H':		/* Home (xterm) */
       								input_home(&cursor);
 								break;
 							case 'F':		/* End (xterm_ */
 								input_end(&cursor, len);
 								break;
 						}
 					}

 					c = 0;
 					break;

 				default:				/* If it's regular input, do the normal thing */
 					if (!isprint(c))		/* Skip non-printable characters */
 						break;

 	       				if (len >= (BUFSIZ - 2))	/* Need to leave space for enter */
 		  				break;

 					len++;

 					if (cursor == (len - 1)) {	/* Append if at the end of the line */
 						*(parsenextc + cursor) = c;
 					} else {			/* Insert otherwise */
 						memmove(parsenextc + cursor + 1, parsenextc + cursor,
 							len - cursor - 1);

 						*(parsenextc + cursor) = c;

 						for (j = cursor; j < len; j++)
 							out1c(*(parsenextc + j));
 						for (; j > cursor; j--)
 							out1str("\033[D");
 					}

 					cursor++;
 					out1c(c);
 					flushout(out1);
 					break;
 			}

 			if (break_out)		/* Enter is the command terminator, no more input. */
 				break;
 		}

 		nr = len + 1;
 		tcsetattr(0, TCSANOW, &old_term);

 		if (*(parsenextc)) {		/* Handle command history log */
 			struct history *h = his_end;

 			if (!h) {       /* No previous history */
 				h = his_front = malloc(sizeof (struct history));
 				h->n = malloc(sizeof (struct history));
 				h->p = NULL;
 				h->s = strdup(parsenextc);

 				h->n->p = h;
 				h->n->n = NULL;
 				h->n->s = NULL;
 				his_end = h->n;
 				history_counter++;
 			} else {	/* Add a new history command */

 				h->n = malloc(sizeof (struct history));

 				h->n->p = h;
 				h->n->n = NULL;
 				h->n->s = NULL;
 				h->s = strdup(parsenextc);
 				his_end = h->n;

 				if (history_counter >= MAX_HISTORY) {	/* After max history, remove the last known command */
 					struct history *p = his_front->n;

 					p->p = NULL;
 					free(his_front->s);
 					free(his_front);
 					his_front = p;
 				} else {
 					history_counter++;
 				}
 			}
 		}
 	}

 	return nr;
 }
	/*
	* Termios command line History and Editting for NetBSD sh (ash)
	* Copyright (c) 1999
	* Main code: Adam Rogoyski <rogoyski@cs.utexas.edu>
	* Etc: Dave Cinege <dcinege@psychosis.com>
	*
	* You may use this code as you wish, so long as the original author(s)
	* are attributed in any redistributions of the source code.
	* This code is 'as is' with no warranty.
	* This code may safely be consumed by a BSD or GPL license.
	*
	* v 0.5 19990328 Initial release
	*
	* Future plans: Simple file and path name completion. (like BASH)
	*
	*/

	/*
	Usage and Known bugs:
	Terminal key codes are not extensive, and more will probably
	need to be added. This version was created on Debian GNU/Linux 2.x.
	Delete, Backspace, Home, End, and the arrow keys were tested
	to work in an Xterm and console. Ctrl-A also works as Home.
	Ctrl-E also works as End. Ctrl-D and Ctrl-U perform their respective
	functions. The binary size increase is <3K.

	Editting will not display correctly for lines greater then the
	terminal width. (more then one line.) However, history will.
	*/

	#include <stdio.h>
	#include <unistd.h>
	#include <stdlib.h>
	#include <string.h>
	#include <termios.h>
	#include <ctype.h>
	#include <sys/ioctl.h>

	#include "input.h"
	#include "output.h"

	#include "hetio.h"


	#define MAX_HISTORY 15 /* Maximum length of the linked list for the command line history */

	#define ESC 27
	#define DEL 127

	static struct history his_front = NULL; / First element in command line list */
	static struct history his_end = NULL; / Last element in command line list */
	static struct termios old_term, new_term; /* Current termio and the previous termio before starting ash */

	static int history_counter = 0; /* Number of commands in history list */
	static int reset_term = 0; /* Set to true if the terminal needs to be reset upon exit */
	static int hetio_inter = 0;

	struct history
	{
	char *s;
	struct history *p;
	struct history *n;
	};


	void input_delete (int);
	void input_home (int *);
	void input_end (int *, int);
	void input_backspace (int , int );



	void hetio_init(void)
	{
	hetio_inter = 1;
	}


	void hetio_reset_term(void)
	{
	if (reset_term)
	tcsetattr(1, TCSANOW, &old_term);
	}


	void setIO(struct termios new, struct termios old) /* Set terminal IO to canonical mode, and save old term settings. */
	{
	tcgetattr(0, old);
	memcpy(new, old, sizeof(*new));
	new->c_cc[VMIN] = 1;
	new->c_cc[VTIME] = 0;
	new->c_lflag &= ~ICANON; /* unbuffered input */
	new->c_lflag &= ~ECHO;
	tcsetattr(0, TCSANOW, new);
	}

	void input_home(int cursor) / Command line input routines */
	{
	while (*cursor > 0) {
	out1c('\b');
	--*cursor;
	}
	flushout(out1);
	}


	void input_delete(int cursor)
	{
	int j = 0;

	memmove(parsenextc + cursor, parsenextc + cursor + 1,
	BUFSIZ - cursor - 1);
	for (j = cursor; j < (BUFSIZ - 1); j++) {
	if (!*(parsenextc + j))
	break;
	else
	out1c(*(parsenextc + j));
	}

	out1str(" \b");

	while (j-- > cursor)
	out1c('\b');
	flushout(out1);
	}


	void input_end(int *cursor, int len)
	{
	while (*cursor < len) {
	out1str("\033[C");
	++*cursor;
	}
	flushout(out1);
	}


	void
	input_backspace(int cursor, int len)
	{
	int j = 0;

	if (*cursor > 0) {
	out1str("\b \b");
	--*cursor;
	memmove(parsenextc + cursor, parsenextc + cursor + 1,
	BUFSIZ - *cursor + 1);

	for (j = *cursor; j < (BUFSIZ - 1); j++) {
	if (!*(parsenextc + j))
	break;
	else
	out1c(*(parsenextc + j));
	}

	out1str(" \b");

	while (j-- > *cursor)
	out1c('\b');

	--*len;
	flushout(out1);
	}
	}

	int hetio_read_input(int fd)
	{
	int nr = 0;

	/* Are we an interactive shell? */
	if (!hetio_inter \|\| fd) {
	return -255;
	} else {
	int len = 0;
	int j = 0;
	int cursor = 0;
	int break_out = 0;
	int ret = 0;
	char c = 0;
	struct history *hp = his_end;

	if (!reset_term) {
	setIO(&new_term, &old_term);
	reset_term = 1;
	} else {
	tcsetattr(0, TCSANOW, &new_term);
	}

	memset(parsenextc, 0, BUFSIZ);

	while (1) {
	if ((ret = read(fd, &c, 1)) < 1)
	return ret;

	switch (c) {
	case 1: /* Control-A Beginning of line */
	input_home(&cursor);
	break;
	case 5: /* Control-E EOL */
	input_end(&cursor, len);
	break;
	case 4: /* Control-D */
	if (!len)
	exitshell(0);
	break;
	case 21: /* Control-U */
	/* Return to begining of line. */
	for (; cursor > 0; cursor--)
	out1c('\b');
	/* Erase old command. */
	for (j = 0; j < len; j++) {
	/*
	* Clear buffer while we're at
	* it.
	*/
	parsenextc[j] = 0;
	out1c(' ');
	}
	/* return to begining of line */
	for (; len > 0; len--)
	out1c('\b');
	flushout(out1);
	break;
	case '\b': /* Backspace */
	case DEL:
	input_backspace(&cursor, &len);
	break;
	case '\n': /* Enter */
	*(parsenextc + len++ + 1) = c;
	out1c(c);
	flushout(out1);
	break_out = 1;
	break;
	case ESC: /* escape sequence follows */
	if ((ret = read(fd, &c, 1)) < 1)
	return ret;

	if (c == '[' ) { /* 91 */
	if ((ret = read(fd, &c, 1)) < 1)
	return ret;

	switch (c) {
	case 'A':
	if (hp && hp->p) { /* Up */
	hp = hp->p;
	goto hop;
	}
	break;
	case 'B':
	if (hp && hp->n && hp->n->s) { /* Down */
	hp = hp->n;
	goto hop;
	}
	break;

	hop: /* hop */
	len = strlen(parsenextc);

	for (; cursor > 0; cursor--) /* return to begining of line */
	out1c('\b');

	for (j = 0; j < len; j++) /* erase old command */
	out1c(' ');

	for (; j > 0; j--) /* return to begining of line */
	out1c('\b');

	strcpy (parsenextc, hp->s); /* write new command */
	len = strlen (hp->s);
	out1str(parsenextc);
	flushout(out1);
	cursor = len;
	break;
	case 'C': /* Right */
	if (cursor < len) {
	out1str("\033[C");
	cursor++;
	flushout(out1);
	}
	break;
	case 'D': /* Left */
	if (cursor > 0) {
	out1str("\033[D");
	cursor--;
	flushout(out1);
	}
	break;
	case '3': /* Delete */
	if (cursor != len) {
	input_delete(cursor);
	len--;
	}
	break;
	case '1': /* Home (Ctrl-A) */
	input_home(&cursor);
	break;
	case '4': /* End (Ctrl-E) */
	input_end(&cursor, len);
	break;
	}
	if (c == '1' \|\| c == '3' \|\| c == '4')
	if ((ret = read(fd, &c, 1)) < 1)
	return ret; /* read 126 (~) */
	}

	if (c == 'O') { /* 79 */
	if ((ret = read(fd, &c, 1)) < 1)
	return ret;
	switch (c) {
	case 'H': /* Home (xterm) */
	input_home(&cursor);
	break;
	case 'F': /* End (xterm_ */
	input_end(&cursor, len);
	break;
	}
	}

	c = 0;
	break;

	default: /* If it's regular input, do the normal thing */
	if (!isprint(c)) /* Skip non-printable characters */
	break;

	if (len >= (BUFSIZ - 2)) /* Need to leave space for enter */
	break;

	len++;

	if (cursor == (len - 1)) { /* Append if at the end of the line */
	*(parsenextc + cursor) = c;
	} else { /* Insert otherwise */
	memmove(parsenextc + cursor + 1, parsenextc + cursor,
	len - cursor - 1);

	*(parsenextc + cursor) = c;

	for (j = cursor; j < len; j++)
	out1c(*(parsenextc + j));
	for (; j > cursor; j--)
	out1str("\033[D");
	}

	cursor++;
	out1c(c);
	flushout(out1);
	break;
	}

	if (break_out) /* Enter is the command terminator, no more input. */
	break;
	}

	nr = len + 1;
	tcsetattr(0, TCSANOW, &old_term);

	if ((parsenextc)) { / Handle command history log */
	struct history *h = his_end;

	if (!h) { /* No previous history */
	h = his_front = malloc(sizeof (struct history));
	h->n = malloc(sizeof (struct history));
	h->p = NULL;
	h->s = strdup(parsenextc);

	h->n->p = h;
	h->n->n = NULL;
	h->n->s = NULL;
	his_end = h->n;
	history_counter++;
	} else { /* Add a new history command */

	h->n = malloc(sizeof (struct history));

	h->n->p = h;
	h->n->n = NULL;
	h->n->s = NULL;
	h->s = strdup(parsenextc);
	his_end = h->n;

	if (history_counter >= MAX_HISTORY) { /* After max history, remove the last known command */
	struct history *p = his_front->n;

	p->p = NULL;
	free(his_front->s);
	free(his_front);
	his_front = p;
	} else {
	history_counter++;
	}
	}
	}
	}

	return nr;
	}