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-rw-r--r--shell/cmdedit.c405
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diff --git a/shell/cmdedit.c b/shell/cmdedit.c
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+++ b/shell/cmdedit.c
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+/*
+ * 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>
+ * Adjusted 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 <termio.h>
+#include <ctype.h>
+#include <signal.h>
+
+#include "cmdedit.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 termio 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 */
+char *parsenextc; /* copy of parsefile->nextc */
+
+struct history {
+ char *s;
+ struct history *p;
+ struct history *n;
+};
+
+
+/* Version of write which resumes after a signal is caught. */
+int xwrite(int fd, char *buf, int nbytes)
+{
+ int ntry;
+ int i;
+ int n;
+
+ n = nbytes;
+ ntry = 0;
+ for (;;) {
+ i = write(fd, buf, n);
+ if (i > 0) {
+ if ((n -= i) <= 0)
+ return nbytes;
+ buf += i;
+ ntry = 0;
+ } else if (i == 0) {
+ if (++ntry > 10)
+ return nbytes - n;
+ } else if (errno != EINTR) {
+ return -1;
+ }
+ }
+}
+
+
+/* Version of ioctl that retries after a signal is caught. */
+int xioctl(int fd, unsigned long request, char *arg)
+{
+ int i;
+ while ((i = ioctl(fd, request, arg)) == -1 && errno == EINTR);
+ return i;
+}
+
+
+void cmdedit_reset_term(void)
+{
+ if (reset_term)
+ xioctl(fileno(stdin), TCSETA, (void *) &old_term);
+}
+
+void gotaSignal(int sig)
+{
+ cmdedit_reset_term();
+ fprintf(stdout, "\n");
+ exit(TRUE);
+}
+
+void input_home(int outputFd, int *cursor)
+{ /* Command line input routines */
+ while (*cursor > 0) {
+ xwrite(outputFd, "\b", 1);
+ --*cursor;
+ }
+}
+
+
+void input_delete(int outputFd, 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
+ xwrite(outputFd, (parsenextc + j), 1);
+ }
+
+ xwrite(outputFd, " \b", 2);
+
+ while (j-- > cursor)
+ xwrite(outputFd, "\b", 1);
+}
+
+
+void input_end(int outputFd, int *cursor, int len)
+{
+ while (*cursor < len) {
+ xwrite(outputFd, "\033[C", 3);
+ ++*cursor;
+ }
+}
+
+
+void input_backspace(int outputFd, int *cursor, int *len)
+{
+ int j = 0;
+
+ if (*cursor > 0) {
+ xwrite(outputFd, "\b \b", 3);
+ --*cursor;
+ memmove(parsenextc + *cursor, parsenextc + *cursor + 1,
+ BUFSIZ - *cursor + 1);
+
+ for (j = *cursor; j < (BUFSIZ - 1); j++) {
+ if (!*(parsenextc + j))
+ break;
+ else
+ xwrite(outputFd, (parsenextc + j), 1);
+ }
+
+ xwrite(outputFd, " \b", 2);
+
+ while (j-- > *cursor)
+ xwrite(outputFd, "\b", 1);
+
+ --*len;
+ }
+}
+
+extern int cmdedit_read_input(int inputFd, int outputFd,
+ char command[BUFSIZ])
+{
+
+ int nr = 0;
+ int len = 0;
+ int j = 0;
+ int cursor = 0;
+ int break_out = 0;
+ int ret = 0;
+ char c = 0;
+ struct history *hp = his_end;
+
+ memset(command, 0, sizeof(command));
+ parsenextc = command;
+ if (!reset_term) {
+ xioctl(inputFd, TCGETA, (void *) &old_term);
+ memcpy(&new_term, &old_term, sizeof(struct termio));
+ new_term.c_cc[VMIN] = 1;
+ new_term.c_cc[VTIME] = 0;
+ new_term.c_lflag &= ~ICANON; /* unbuffered input */
+ new_term.c_lflag &= ~ECHO;
+ xioctl(inputFd, TCSETA, (void *) &new_term);
+ reset_term = 1;
+ } else {
+ xioctl(inputFd, TCSETA, (void *) &new_term);
+ }
+
+ memset(parsenextc, 0, BUFSIZ);
+
+ while (1) {
+
+ if ((ret = read(inputFd, &c, 1)) < 1)
+ return ret;
+
+ switch (c) {
+ case 1: /* Control-A Beginning of line */
+ input_home(outputFd, &cursor);
+ break;
+ case 5: /* Control-E EOL */
+ input_end(outputFd, &cursor, len);
+ break;
+ case 4: /* Control-D */
+ if (cursor != len) {
+ input_delete(outputFd, cursor);
+ len--;
+ }
+ break;
+ case '\b': /* Backspace */
+ case DEL:
+ input_backspace(outputFd, &cursor, &len);
+ break;
+ case '\n': /* Enter */
+ *(parsenextc + len++ + 1) = c;
+ xwrite(outputFd, &c, 1);
+ break_out = 1;
+ break;
+ case ESC: /* escape sequence follows */
+ if ((ret = read(inputFd, &c, 1)) < 1)
+ return ret;
+
+ if (c == '[') { /* 91 */
+ if ((ret = read(inputFd, &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 */
+ xwrite(outputFd, "\b", 1);
+
+ for (j = 0; j < len; j++) /* erase old command */
+ xwrite(outputFd, " ", 1);
+
+ for (j = len; j > 0; j--) /* return to begining of line */
+ xwrite(outputFd, "\b", 1);
+
+ strcpy(parsenextc, hp->s); /* write new command */
+ len = strlen(hp->s);
+ xwrite(outputFd, parsenextc, len);
+ cursor = len;
+ break;
+ case 'C': /* Right */
+ if (cursor < len) {
+ xwrite(outputFd, "\033[C", 3);
+ cursor++;
+ }
+ break;
+ case 'D': /* Left */
+ if (cursor > 0) {
+ xwrite(outputFd, "\033[D", 3);
+ cursor--;
+ }
+ break;
+ case '3': /* Delete */
+ if (cursor != len) {
+ input_delete(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;
+ }
+ if (c == '1' || c == '3' || c == '4')
+ if ((ret = read(inputFd, &c, 1)) < 1)
+ return ret; /* read 126 (~) */
+ }
+ if (c == 'O') { /* 79 */
+ if ((ret = read(inputFd, &c, 1)) < 1)
+ return ret;
+ switch (c) {
+ case 'H': /* Home (xterm) */
+ input_home(outputFd, &cursor);
+ break;
+ case 'F': /* End (xterm) */
+ input_end(outputFd, &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++)
+ xwrite(outputFd, parsenextc + j, 1);
+ for (; j > cursor; j--)
+ xwrite(outputFd, "\033[D", 3);
+ }
+
+ cursor++;
+ xwrite(outputFd, &c, 1);
+ break;
+ }
+
+ if (break_out) /* Enter is the command terminator, no more input. */
+ break;
+ }
+
+ nr = len + 1;
+ xioctl(inputFd, TCSETA, (void *) &old_term);
+ reset_term = 0;
+
+
+ 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;
+}
+
+extern void cmdedit_init(void)
+{
+ atexit(cmdedit_reset_term);
+ signal(SIGINT, gotaSignal);
+ signal(SIGQUIT, gotaSignal);
+ signal(SIGTERM, gotaSignal);
+}
+#endif /* BB_FEATURE_SH_COMMAND_EDITING */
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