busybox/shell/cmdedit.c
Eric Andersen 72965e3454 Fixed a potential infinite loop. First delete any chars after the
cursor, then delete everything before it.  Before this, we would just
delete everything before the cursor and freak out if there were still
chars left (i.e. stuff after the cursor).
 -Erik
2000-07-04 06:22:18 +00:00

701 lines
17 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 "internal.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 */
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 */
struct history {
char *s;
struct history *p;
struct history *n;
};
#define xwrite write
void
cmdedit_setwidth(int w)
{
if (w > 20) {
cmdedit_termw = w;
cmdedit_scroll = w / 3;
} else {
errorMsg("\n*** Error: minimum screen width is 21\n");
}
}
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);
}
void clean_up_and_die(int sig)
{
cmdedit_reset_term();
fprintf(stdout, "\n");
if (sig!=SIGINT)
exit(TRUE);
}
/* Go to HOME position */
void input_home(int outputFd, int *cursor)
{
while (*cursor > 0) {
xwrite(outputFd, "\b", 1);
--*cursor;
}
}
/* Go to END position */
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 */
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 */
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 */
void input_forward(int outputFd, int *cursor, int len)
{
if (*cursor < len) {
xwrite(outputFd, "\033[C", 3);
++*cursor;
}
}
/* Move back one charactor */
void input_backward(int outputFd, int *cursor)
{
if (*cursor > 0) {
xwrite(outputFd, "\033[D", 3);
--*cursor;
}
}
#ifdef BB_FEATURE_SH_TAB_COMPLETION
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>
char** exe_n_cwd_tab_completion(char* command, int *num_matches)
{
char *dirName;
char **matches = (char **) NULL;
DIR *dir;
struct dirent *next;
matches = malloc( 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] = malloc(strlen(next->d_name)+1);
strcpy( matches[*num_matches], next->d_name);
++*num_matches;
//matches = realloc( matches, sizeof(char*)*(*num_matches));
}
}
return (matches);
}
void input_tab(char* command, char* prompt, int outputFd, int *cursor, int *len)
{
/* 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 *) calloc(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);
break;
}
} 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
void get_previous_history(struct history **hp, char* command)
{
free((*hp)->s);
(*hp)->s = strdup(command);
*hp = (*hp)->p;
}
void get_next_history(struct history **hp, char* command)
{
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;
memset(command, 0, sizeof(command));
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);
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 -- leave the current line,
* and start over on the next line */
/* Go to the next line */
xwrite(outputFd, "\n", 1);
/* Rewrite the prompt */
xwrite(outputFd, prompt, strlen(prompt));
/* Reset the command string */
memset(command, 0, sizeof(command));
len = cursor = 0;
break;
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);
#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 */
h = his_front = malloc(sizeof(struct history));
h->n = malloc(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 */
h->n = malloc(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)
{
atexit(cmdedit_reset_term);
signal(SIGKILL, clean_up_and_die);
signal(SIGINT, clean_up_and_die);
signal(SIGQUIT, clean_up_and_die);
signal(SIGTERM, clean_up_and_die);
}
#endif /* BB_FEATURE_SH_COMMAND_EDITING */