busybox/shell/cmdedit.c
2001-01-18 02:57:08 +00:00

768 lines
18 KiB
C

/* vi: set sw=4 ts=4: */
/*
* Termios command line History and Editting, originally
* intended for NetBSD sh (ash)
* Copyright (c) 1999
* Main code: Adam Rogoyski <rogoyski@cs.utexas.edu>
* Etc: Dave Cinege <dcinege@psychosis.com>
* Majorly adjusted/re-written for busybox:
* Erik Andersen <andersee@debian.org>
*
* 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. 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 "busybox.h"
#ifdef BB_FEATURE_SH_COMMAND_EDITING
#include <stdio.h>
#include <errno.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <sys/ioctl.h>
#include <ctype.h>
#include <signal.h>
#define MAX_HISTORY 15 /* Maximum length of the linked list for the command line history */
#define ESC 27
#define DEL 127
#define member(c, s) ((c) ? ((char *)strchr ((s), (c)) != (char *)NULL) : 0)
#define whitespace(c) (((c) == ' ') || ((c) == '\t'))
static struct history *his_front = NULL; /* First element in command line list */
static struct history *his_end = NULL; /* Last element in command line list */
/* ED: sparc termios is broken: revert back to old termio handling. */
#ifdef BB_FEATURE_USE_TERMIOS
#if #cpu(sparc)
# include <termio.h>
# define termios termio
# define setTermSettings(fd,argp) ioctl(fd,TCSETAF,argp)
# define getTermSettings(fd,argp) ioctl(fd,TCGETA,argp)
#else
# include <termios.h>
# define setTermSettings(fd,argp) tcsetattr(fd,TCSANOW,argp)
# define getTermSettings(fd,argp) tcgetattr(fd, argp);
#endif
/* Current termio and the previous termio before starting sh */
static struct termios initial_settings, new_settings;
#ifndef _POSIX_VDISABLE
#define _POSIX_VDISABLE '\0'
#endif
#endif
static int cmdedit_termw = 80; /* actual terminal width */
static int cmdedit_scroll = 27; /* width of EOL scrolling region */
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 exithandler_set = 0; /* Set to true when atexit() has been called */
/* Link into lash to reset context to 0
* on ^C and such */
extern unsigned int shell_context;
struct history {
char *s;
struct history *p;
struct history *n;
};
#define xwrite write
/*
* TODO: Someday we want to implement 'horizontal scrolling' of the
* command-line when the user has typed more than the current width. This
* would allow the user to see a 'window' of what he has typed.
*/
static void cmdedit_setwidth(int w)
{
if (w > 20) {
cmdedit_termw = w;
cmdedit_scroll = w / 3;
} else {
error_msg("\n*** Error: minimum screen width is 21\n");
}
}
static void win_changed(int junk)
{
struct winsize win = { 0, 0, 0, 0 };
ioctl(0, TIOCGWINSZ, &win);
if (win.ws_col > 0) {
cmdedit_setwidth( win.ws_col - 1);
}
}
static void cmdedit_reset_term(void)
{
if (reset_term)
/* sparc and other have broken termios support: use old termio handling. */
setTermSettings(fileno(stdin), (void*) &initial_settings);
#ifdef BB_FEATURE_CLEAN_UP
if (his_front) {
struct history *n;
//while(his_front!=his_end) {
while(his_front!=his_end) {
n = his_front->n;
free(his_front->s);
free(his_front);
his_front=n;
}
}
#endif
}
static void clean_up_and_die(int sig)
{
cmdedit_reset_term();
printf("\n");
if (sig!=SIGINT)
exit(EXIT_SUCCESS);
}
/* Go to HOME position */
static void input_home(int outputFd, int *cursor)
{
while (*cursor > 0) {
xwrite(outputFd, "\b", 1);
--*cursor;
}
}
/* Go to END position */
static void input_end(int outputFd, int *cursor, int len)
{
while (*cursor < len) {
xwrite(outputFd, "\033[C", 3);
++*cursor;
}
}
/* Delete the char in back of the cursor */
static void input_backspace(char* command, int outputFd, int *cursor, int *len)
{
int j = 0;
/* Debug crap */
//fprintf(stderr, "\nerik: len=%d, cursor=%d, strlen(command)='%d'\n", *len, *cursor, strlen(command));
//xwrite(outputFd, command, *len);
//*cursor = *len;
if (*cursor > 0) {
xwrite(outputFd, "\b \b", 3);
--*cursor;
memmove(command + *cursor, command + *cursor + 1,
BUFSIZ - *cursor + 1);
for (j = *cursor; j < (BUFSIZ - 1); j++) {
if (!*(command + j))
break;
else
xwrite(outputFd, (command + j), 1);
}
xwrite(outputFd, " \b", 2);
while (j-- > *cursor)
xwrite(outputFd, "\b", 1);
--*len;
}
}
/* Delete the char in front of the cursor */
static void input_delete(char* command, int outputFd, int cursor, int *len)
{
int j = 0;
if (cursor == *len)
return;
memmove(command + cursor, command + cursor + 1,
BUFSIZ - cursor - 1);
for (j = cursor; j < (BUFSIZ - 1); j++) {
if (!*(command + j))
break;
else
xwrite(outputFd, (command + j), 1);
}
xwrite(outputFd, " \b", 2);
while (j-- > cursor)
xwrite(outputFd, "\b", 1);
--*len;
}
/* Move forward one charactor */
static void input_forward(int outputFd, int *cursor, int len)
{
if (*cursor < len) {
xwrite(outputFd, "\033[C", 3);
++*cursor;
}
}
/* Move back one charactor */
static void input_backward(int outputFd, int *cursor)
{
if (*cursor > 0) {
xwrite(outputFd, "\033[D", 3);
--*cursor;
}
}
#ifdef BB_FEATURE_SH_TAB_COMPLETION
static char** username_tab_completion(char* command, int *num_matches)
{
char **matches = (char **) NULL;
*num_matches=0;
fprintf(stderr, "\nin username_tab_completion\n");
return (matches);
}
#include <dirent.h>
static char** exe_n_cwd_tab_completion(char* command, int *num_matches)
{
char *dirName;
char **matches;
DIR *dir;
struct dirent *next;
matches = xmalloc( sizeof(char*)*50);
/* Stick a wildcard onto the command, for later use */
strcat( command, "*");
/* Now wall the current directory */
dirName = get_current_dir_name();
dir = opendir(dirName);
if (!dir) {
/* Don't print an error, just shut up and return */
*num_matches=0;
return (matches);
}
while ((next = readdir(dir)) != NULL) {
/* Some quick sanity checks */
if ((strcmp(next->d_name, "..") == 0)
|| (strcmp(next->d_name, ".") == 0)) {
continue;
}
/* See if this matches */
if (check_wildcard_match(next->d_name, command) == TRUE) {
/* Cool, found a match. Add it to the list */
matches[*num_matches] = xmalloc(strlen(next->d_name)+1);
strcpy( matches[*num_matches], next->d_name);
++*num_matches;
//matches = realloc( matches, sizeof(char*)*(*num_matches));
}
}
return (matches);
}
static void input_tab(char* command, char* prompt, int outputFd, int *cursor, int *len, int lastWasTab)
{
/* Do TAB completion */
static int num_matches=0;
static char **matches = (char **) NULL;
int pos = *cursor;
if (lastWasTab == FALSE) {
char *tmp, *tmp1, *matchBuf;
/* For now, we will not bother with trying to distinguish
* whether the cursor is in/at a command extression -- we
* will always try all possible matches. If you don't like
* that then feel free to fix it.
*/
/* Make a local copy of the string -- up
* to the position of the cursor */
matchBuf = (char *) xcalloc(BUFSIZ, sizeof(char));
strncpy(matchBuf, command, *cursor);
tmp=matchBuf;
/* skip past any command seperator tokens */
while (*tmp && (tmp1=strpbrk(tmp, ";|&{(`")) != NULL) {
tmp=++tmp1;
/* skip any leading white space */
while (*tmp && isspace(*tmp))
++tmp;
}
/* skip any leading white space */
while (*tmp && isspace(*tmp))
++tmp;
/* Free up any memory already allocated */
if (matches) {
free(matches);
matches = (char **) NULL;
}
/* If the word starts with `~' and there is no slash in the word,
* then try completing this word as a username. */
/* FIXME -- this check is broken! */
if (*tmp == '~' && !strchr(tmp, '/'))
matches = username_tab_completion(tmp, &num_matches);
/* Try to match any executable in our path and everything
* in the current working directory that matches. */
if (!matches)
matches = exe_n_cwd_tab_completion(tmp, &num_matches);
/* Don't leak memory */
free( matchBuf);
/* Did we find exactly one match? */
if (matches && num_matches==1) {
/* write out the matched command */
strncpy(command+pos, matches[0]+pos, strlen(matches[0])-pos);
*len=strlen(command);
*cursor=*len;
xwrite(outputFd, matches[0]+pos, strlen(matches[0])-pos);
return;
}
} else {
/* Ok -- the last char was a TAB. Since they
* just hit TAB again, print a list of all the
* available choices... */
if ( matches && num_matches>0 ) {
int i, col;
/* Go to the next line */
xwrite(outputFd, "\n", 1);
/* Print the list of matches */
for (i=0,col=0; i<num_matches; i++) {
char foo[17];
sprintf(foo, "%-14s ", matches[i]);
col += xwrite(outputFd, foo, strlen(foo));
if (col > 60 && matches[i+1] != NULL) {
xwrite(outputFd, "\n", 1);
col = 0;
}
}
/* Go to the next line */
xwrite(outputFd, "\n", 1);
/* Rewrite the prompt */
xwrite(outputFd, prompt, strlen(prompt));
/* Rewrite the command */
xwrite(outputFd, command, *len);
/* Put the cursor back to where it used to be */
for (cursor=len; *cursor > pos; cursor--)
xwrite(outputFd, "\b", 1);
}
}
}
#endif
static void get_previous_history(struct history **hp, char* command)
{
if ((*hp)->s)
free((*hp)->s);
(*hp)->s = strdup(command);
*hp = (*hp)->p;
}
static void get_next_history(struct history **hp, char* command)
{
if ((*hp)->s)
free((*hp)->s);
(*hp)->s = strdup(command);
*hp = (*hp)->n;
}
/*
* This function is used to grab a character buffer
* from the input file descriptor and allows you to
* a string with full command editing (sortof like
* a mini readline).
*
* The following standard commands are not implemented:
* ESC-b -- Move back one word
* ESC-f -- Move forward one word
* ESC-d -- Delete back one word
* ESC-h -- Delete forward one word
* CTL-t -- Transpose two characters
*
* Furthermore, the "vi" command editing keys are not implemented.
*
* TODO: implement TAB command completion. :)
*/
extern void cmdedit_read_input(char* prompt, char command[BUFSIZ])
{
int inputFd=fileno(stdin);
int outputFd=fileno(stdout);
int nr = 0;
int len = 0;
int j = 0;
int cursor = 0;
int break_out = 0;
int ret = 0;
int lastWasTab = FALSE;
char c = 0;
struct history *hp = his_end;
if (!reset_term) {
getTermSettings(inputFd, (void*) &initial_settings);
memcpy(&new_settings, &initial_settings, sizeof(struct termios));
new_settings.c_cc[VMIN] = 1;
new_settings.c_cc[VTIME] = 0;
new_settings.c_cc[VINTR] = _POSIX_VDISABLE; /* Turn off CTRL-C, so we can trap it */
new_settings.c_lflag &= ~ICANON; /* unbuffered input */
new_settings.c_lflag &= ~(ECHO|ECHOCTL|ECHONL); /* Turn off echoing */
reset_term = 1;
}
setTermSettings(inputFd, (void*) &new_settings);
memset(command, 0, BUFSIZ);
/* Print out the command prompt */
xwrite(outputFd, prompt, strlen(prompt));
while (1) {
if ((ret = read(inputFd, &c, 1)) < 1)
return;
//fprintf(stderr, "got a '%c' (%d)\n", c, c);
switch (c) {
case '\n':
case '\r':
/* Enter */
*(command + len++ + 1) = c;
xwrite(outputFd, &c, 1);
break_out = 1;
break;
case 1:
/* Control-a -- Beginning of line */
input_home(outputFd, &cursor);
case 2:
/* Control-b -- Move back one character */
input_backward(outputFd, &cursor);
break;
case 3:
/* Control-c -- stop gathering input */
/* Link into lash to reset context to 0 on ^C and such */
shell_context = 0;
/* Go to the next line */
xwrite(outputFd, "\n", 1);
#if 0
/* Rewrite the prompt */
xwrite(outputFd, prompt, strlen(prompt));
/* Reset the command string */
memset(command, 0, BUFSIZ);
len = cursor = 0;
#endif
return;
case 4:
/* Control-d -- Delete one character, or exit
* if the len=0 and no chars to delete */
if (len == 0) {
xwrite(outputFd, "exit", 4);
clean_up_and_die(0);
} else {
input_delete(command, outputFd, cursor, &len);
}
break;
case 5:
/* Control-e -- End of line */
input_end(outputFd, &cursor, len);
break;
case 6:
/* Control-f -- Move forward one character */
input_forward(outputFd, &cursor, len);
break;
case '\b':
case DEL:
/* Control-h and DEL */
input_backspace(command, outputFd, &cursor, &len);
break;
case '\t':
#ifdef BB_FEATURE_SH_TAB_COMPLETION
input_tab(command, prompt, outputFd, &cursor,
&len, lastWasTab);
#endif
break;
case 14:
/* Control-n -- Get next command in history */
if (hp && hp->n && hp->n->s) {
get_next_history(&hp, command);
goto rewrite_line;
} else {
xwrite(outputFd, "\007", 1);
}
break;
case 16:
/* Control-p -- Get previous command from history */
if (hp && hp->p) {
get_previous_history(&hp, command);
goto rewrite_line;
} else {
xwrite(outputFd, "\007", 1);
}
break;
case ESC:{
/* escape sequence follows */
if ((ret = read(inputFd, &c, 1)) < 1)
return;
if (c == '[') { /* 91 */
if ((ret = read(inputFd, &c, 1)) < 1)
return;
switch (c) {
case 'A':
/* Up Arrow -- Get previous command from history */
if (hp && hp->p) {
get_previous_history(&hp, command);
goto rewrite_line;
} else {
xwrite(outputFd, "\007", 1);
}
break;
case 'B':
/* Down Arrow -- Get next command in history */
if (hp && hp->n && hp->n->s) {
get_next_history(&hp, command);
goto rewrite_line;
} else {
xwrite(outputFd, "\007", 1);
}
break;
/* Rewrite the line with the selected history item */
rewrite_line:
/* erase old command from command line */
len = strlen(command)-strlen(hp->s);
while (len>cursor)
input_delete(command, outputFd, cursor, &len);
while (cursor>0)
input_backspace(command, outputFd, &cursor, &len);
input_home(outputFd, &cursor);
/* write new command */
strcpy(command, hp->s);
len = strlen(hp->s);
xwrite(outputFd, command, len);
cursor = len;
break;
case 'C':
/* Right Arrow -- Move forward one character */
input_forward(outputFd, &cursor, len);
break;
case 'D':
/* Left Arrow -- Move back one character */
input_backward(outputFd, &cursor);
break;
case '3':
/* Delete */
input_delete(command, outputFd, cursor, &len);
break;
case '1':
/* Home (Ctrl-A) */
input_home(outputFd, &cursor);
break;
case '4':
/* End (Ctrl-E) */
input_end(outputFd, &cursor, len);
break;
default:
xwrite(outputFd, "\007", 1);
}
if (c == '1' || c == '3' || c == '4')
if ((ret = read(inputFd, &c, 1)) < 1)
return; /* read 126 (~) */
}
if (c == 'O') {
/* 79 */
if ((ret = read(inputFd, &c, 1)) < 1)
return;
switch (c) {
case 'H':
/* Home (xterm) */
input_home(outputFd, &cursor);
break;
case 'F':
/* End (xterm) */
input_end(outputFd, &cursor, len);
break;
default:
xwrite(outputFd, "\007", 1);
}
}
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 */
*(command + cursor) = c;
} else { /* Insert otherwise */
memmove(command + cursor + 1, command + cursor,
len - cursor - 1);
*(command + cursor) = c;
for (j = cursor; j < len; j++)
xwrite(outputFd, command + j, 1);
for (; j > cursor; j--)
xwrite(outputFd, "\033[D", 3);
}
cursor++;
xwrite(outputFd, &c, 1);
break;
}
if (c == '\t')
lastWasTab = TRUE;
else
lastWasTab = FALSE;
if (break_out) /* Enter is the command terminator, no more input. */
break;
}
nr = len + 1;
setTermSettings(inputFd, (void *) &initial_settings);
reset_term = 0;
/* Handle command history log */
if (*(command)) {
struct history *h = his_end;
if (!h) {
/* No previous history -- this memory is never freed */
h = his_front = xmalloc(sizeof(struct history));
h->n = xmalloc(sizeof(struct history));
h->p = NULL;
h->s = strdup(command);
h->n->p = h;
h->n->n = NULL;
h->n->s = NULL;
his_end = h->n;
history_counter++;
} else {
/* Add a new history command -- this memory is never freed */
h->n = xmalloc(sizeof(struct history));
h->n->p = h;
h->n->n = NULL;
h->n->s = NULL;
h->s = strdup(command);
his_end = h->n;
/* After max history, remove the oldest command */
if (history_counter >= MAX_HISTORY) {
struct history *p = his_front->n;
p->p = NULL;
free(his_front->s);
free(his_front);
his_front = p;
} else {
history_counter++;
}
}
}
return;
}
extern void cmdedit_init(void)
{
win_changed(0);
signal(SIGWINCH, win_changed);
if(exithandler_set == 0) {
atexit(cmdedit_reset_term); /* be sure to do this only once */
exithandler_set = 1;
}
signal(SIGKILL, clean_up_and_die);
signal(SIGINT, clean_up_and_die);
signal(SIGQUIT, clean_up_and_die);
signal(SIGTERM, clean_up_and_die);
}
/*
** Undo the effects of cmdedit_init() as good as we can:
** I am not aware of a way to revoke an atexit() handler,
** but, fortunately, our particular handler can be made
** a no-op by setting reset_term = 0.
*/
extern void cmdedit_terminate(void)
{
cmdedit_reset_term();
reset_term = 0;
signal(SIGKILL, SIG_DFL);
signal(SIGINT, SIG_DFL);
signal(SIGQUIT, SIG_DFL);
signal(SIGTERM, SIG_DFL);
signal(SIGWINCH, SIG_DFL);
}
#endif /* BB_FEATURE_SH_COMMAND_EDITING */