* Copyright (C) 2008 Rob Landley <rob@landley.net>
* Copyright (C) 2008 Denys Vlasenko <vda.linux@googlemail.com>
*
- * Licensed under GPL version 2, see file LICENSE in this tarball for details.
+ * Licensed under GPLv2, see file LICENSE in this source tree.
*/
#include "libbb.h"
-int64_t FAST_FUNC read_key(int fd, char *buffer)
+int64_t FAST_FUNC read_key(int fd, char *buffer, int timeout)
{
struct pollfd pfd;
const char *seq;
int n;
- int c;
- /* Known escape sequences for cursor and function keys */
+ /* Known escape sequences for cursor and function keys.
+ * See "Xterm Control Sequences"
+ * http://invisible-island.net/xterm/ctlseqs/ctlseqs.html
+ */
static const char esccmds[] ALIGN1 = {
'O','A' |0x80,KEYCODE_UP ,
'O','B' |0x80,KEYCODE_DOWN ,
#if 0
'O','P' |0x80,KEYCODE_FUN1 ,
/* [ESC] ESC O [2] P - [Alt-][Shift-]F1 */
- /* Ctrl- seems to not affect sequences */
+ /* ESC [ O 1 ; 2 P - Shift-F1 */
+ /* ESC [ O 1 ; 3 P - Alt-F1 */
+ /* ESC [ O 1 ; 4 P - Alt-Shift-F1 */
+ /* ESC [ O 1 ; 5 P - Ctrl-F1 */
+ /* ESC [ O 1 ; 6 P - Ctrl-Shift-F1 */
'O','Q' |0x80,KEYCODE_FUN2 ,
'O','R' |0x80,KEYCODE_FUN3 ,
'O','S' |0x80,KEYCODE_FUN4 ,
'[','B' |0x80,KEYCODE_DOWN ,
'[','C' |0x80,KEYCODE_RIGHT ,
'[','D' |0x80,KEYCODE_LEFT ,
+ /* ESC [ 1 ; 2 x, where x = A/B/C/D: Shift-<arrow> */
+ /* ESC [ 1 ; 3 x, where x = A/B/C/D: Alt-<arrow> - implemented below */
+ /* ESC [ 1 ; 4 x, where x = A/B/C/D: Alt-Shift-<arrow> */
+ /* ESC [ 1 ; 5 x, where x = A/B/C/D: Ctrl-<arrow> - implemented below */
+ /* ESC [ 1 ; 6 x, where x = A/B/C/D: Ctrl-Shift-<arrow> */
+ /* ESC [ 1 ; 7 x, where x = A/B/C/D: Ctrl-Alt-<arrow> */
+ /* ESC [ 1 ; 8 x, where x = A/B/C/D: Ctrl-Alt-Shift-<arrow> */
'[','H' |0x80,KEYCODE_HOME , /* xterm */
- /* [ESC] ESC [ [2] H - [Alt-][Shift-]Home */
'[','F' |0x80,KEYCODE_END , /* xterm */
+ /* [ESC] ESC [ [2] H - [Alt-][Shift-]Home (End similarly?) */
+ /* '[','Z' |0x80,KEYCODE_SHIFT_TAB, */
'[','1','~' |0x80,KEYCODE_HOME , /* vt100? linux vt? or what? */
'[','2','~' |0x80,KEYCODE_INSERT ,
+ /* ESC [ 2 ; 3 ~ - Alt-Insert */
'[','3','~' |0x80,KEYCODE_DELETE ,
/* [ESC] ESC [ 3 [;2] ~ - [Alt-][Shift-]Delete */
+ /* ESC [ 3 ; 3 ~ - Alt-Delete */
+ /* ESC [ 3 ; 5 ~ - Ctrl-Delete */
'[','4','~' |0x80,KEYCODE_END , /* vt100? linux vt? or what? */
'[','5','~' |0x80,KEYCODE_PAGEUP ,
+ /* ESC [ 5 ; 3 ~ - Alt-PgUp */
+ /* ESC [ 5 ; 5 ~ - Ctrl-PgUp */
+ /* ESC [ 5 ; 7 ~ - Ctrl-Alt-PgUp */
'[','6','~' |0x80,KEYCODE_PAGEDOWN,
'[','7','~' |0x80,KEYCODE_HOME , /* vt100? linux vt? or what? */
'[','8','~' |0x80,KEYCODE_END , /* vt100? linux vt? or what? */
#if 0
- '[','1','1','~'|0x80,KEYCODE_FUN1 ,
- '[','1','2','~'|0x80,KEYCODE_FUN2 ,
- '[','1','3','~'|0x80,KEYCODE_FUN3 ,
- '[','1','4','~'|0x80,KEYCODE_FUN4 ,
+ '[','1','1','~'|0x80,KEYCODE_FUN1 , /* old xterm, deprecated by ESC O P */
+ '[','1','2','~'|0x80,KEYCODE_FUN2 , /* old xterm... */
+ '[','1','3','~'|0x80,KEYCODE_FUN3 , /* old xterm... */
+ '[','1','4','~'|0x80,KEYCODE_FUN4 , /* old xterm... */
'[','1','5','~'|0x80,KEYCODE_FUN5 ,
/* [ESC] ESC [ 1 5 [;2] ~ - [Alt-][Shift-]F5 */
'[','1','7','~'|0x80,KEYCODE_FUN6 ,
'[','2','1','~'|0x80,KEYCODE_FUN10 ,
'[','2','3','~'|0x80,KEYCODE_FUN11 ,
'[','2','4','~'|0x80,KEYCODE_FUN12 ,
+ /* ESC [ 2 4 ; 2 ~ - Shift-F12 */
+ /* ESC [ 2 4 ; 3 ~ - Alt-F12 */
+ /* ESC [ 2 4 ; 4 ~ - Alt-Shift-F12 */
+ /* ESC [ 2 4 ; 5 ~ - Ctrl-F12 */
+ /* ESC [ 2 4 ; 6 ~ - Ctrl-Shift-F12 */
#endif
+ /* '[','1',';','5','A' |0x80,KEYCODE_CTRL_UP , - unused */
+ /* '[','1',';','5','B' |0x80,KEYCODE_CTRL_DOWN , - unused */
+ '[','1',';','5','C' |0x80,KEYCODE_CTRL_RIGHT,
+ '[','1',';','5','D' |0x80,KEYCODE_CTRL_LEFT ,
+ /* '[','1',';','3','A' |0x80,KEYCODE_ALT_UP , - unused */
+ /* '[','1',';','3','B' |0x80,KEYCODE_ALT_DOWN , - unused */
+ '[','1',';','3','C' |0x80,KEYCODE_ALT_RIGHT,
+ '[','1',';','3','D' |0x80,KEYCODE_ALT_LEFT ,
+ /* '[','3',';','3','~' |0x80,KEYCODE_ALT_DELETE, - unused */
0
};
+ pfd.fd = fd;
+ pfd.events = POLLIN;
+
+ buffer++; /* saved chars counter is in buffer[-1] now */
+
+ start_over:
errno = 0;
- n = (unsigned char) *buffer++;
+ n = (unsigned char)buffer[-1];
if (n == 0) {
- /* If no data, block waiting for input. If we read more
- * than the minimal ESC sequence size, the "n=0" below
- * would instead have to figure out how much to keep,
- * resulting in larger code. */
- n = safe_read(fd, buffer, 3);
+ /* If no data, wait for input.
+ * If requested, wait TIMEOUT ms. TIMEOUT = -1 is useful
+ * if fd can be in non-blocking mode.
+ */
+ if (timeout >= -1) {
+ if (safe_poll(&pfd, 1, timeout) == 0) {
+ /* Timed out */
+ errno = EAGAIN;
+ return -1;
+ }
+ }
+ /* It is tempting to read more than one byte here,
+ * but it breaks pasting. Example: at shell prompt,
+ * user presses "c","a","t" and then pastes "\nline\n".
+ * When we were reading 3 bytes here, we were eating
+ * "li" too, and cat was getting wrong input.
+ */
+ n = safe_read(fd, buffer, 1);
if (n <= 0)
return -1;
}
- /* Grab character to return from buffer */
- c = (unsigned char)buffer[0];
- n--;
- if (n)
- memmove(buffer, buffer + 1, n);
-
- /* Only ESC starts ESC sequences */
- if (c != 27)
- goto ret;
+ {
+ unsigned char c = buffer[0];
+ n--;
+ if (n)
+ memmove(buffer, buffer + 1, n);
+ /* Only ESC starts ESC sequences */
+ if (c != 27) {
+ buffer[-1] = n;
+ return c;
+ }
+ }
/* Loop through known ESC sequences */
- pfd.fd = fd;
- pfd.events = POLLIN;
seq = esccmds;
while (*seq != '\0') {
/* n - position in sequence we did not read yet */
if (safe_poll(&pfd, 1, 50) == 0) {
/* No more data!
* Array is sorted from shortest to longest,
- * we can't match anything later in array,
- * break out of both loops. */
- goto ret;
+ * we can't match anything later in array -
+ * anything later is longer than this seq.
+ * Break out of both loops. */
+ goto got_all;
}
errno = 0;
if (safe_read(fd, buffer + n, 1) <= 0) {
/* If EAGAIN, then fd is O_NONBLOCK and poll lied:
* in fact, there is no data. */
- if (errno != EAGAIN)
- c = -1; /* otherwise it's EOF/error */
- goto ret;
+ if (errno != EAGAIN) {
+ /* otherwise: it's EOF/error */
+ buffer[-1] = 0;
+ return -1;
+ }
+ goto got_all;
}
n++;
}
}
if (seq[i] & 0x80) {
/* Entire seq matched */
- c = (signed char)seq[i+1];
n = 0;
/* n -= i; memmove(...);
* would be more correct,
* but we never read ahead that much,
* and n == i here. */
- goto ret;
+ buffer[-1] = 0;
+ return (signed char)seq[i+1];
}
i++;
}
}
- /* We did not find matching sequence, it was a bare ESC.
- * We possibly read and stored more input in buffer[] by now. */
-
- /* Try to decipher "ESC [ NNN ; NNN R" sequence */
- if (ENABLE_FEATURE_EDITING_ASK_TERMINAL
- && n != 0
- && buffer[0] == '['
- ) {
- char *end;
- unsigned long row, col;
-
- while (n < KEYCODE_BUFFER_SIZE-1) { /* 1 for cnt */
- if (safe_poll(&pfd, 1, 50) == 0) {
- /* No more data! */
- break;
- }
- errno = 0;
- if (safe_read(fd, buffer + n, 1) <= 0) {
- /* If EAGAIN, then fd is O_NONBLOCK and poll lied:
- * in fact, there is no data. */
- if (errno != EAGAIN)
- c = -1; /* otherwise it's EOF/error */
- goto ret;
+ /* We did not find matching sequence.
+ * We possibly read and stored more input in buffer[] by now.
+ * n = bytes read. Try to read more until we time out.
+ */
+ while (n < KEYCODE_BUFFER_SIZE-1) { /* 1 for count byte at buffer[-1] */
+ if (safe_poll(&pfd, 1, 50) == 0) {
+ /* No more data! */
+ break;
+ }
+ errno = 0;
+ if (safe_read(fd, buffer + n, 1) <= 0) {
+ /* If EAGAIN, then fd is O_NONBLOCK and poll lied:
+ * in fact, there is no data. */
+ if (errno != EAGAIN) {
+ /* otherwise: it's EOF/error */
+ buffer[-1] = 0;
+ return -1;
}
- if (buffer[n++] == 'R')
- goto got_R;
+ break;
}
- goto ret;
- got_R:
- if (!isdigit(buffer[1]))
- goto ret;
- row = strtoul(buffer + 1, &end, 10);
- if (*end != ';' || !isdigit(end[1]))
- goto ret;
- col = strtoul(end + 1, &end, 10);
- if (*end != 'R')
- goto ret;
- if (row < 1 || col < 1 || (row | col) > 0x7fff)
- goto ret;
+ n++;
+ /* Try to decipher "ESC [ NNN ; NNN R" sequence */
+ if ((ENABLE_FEATURE_EDITING_ASK_TERMINAL
+ || ENABLE_FEATURE_VI_ASK_TERMINAL
+ || ENABLE_FEATURE_LESS_ASK_TERMINAL
+ )
+ && n >= 5
+ && buffer[0] == '['
+ && buffer[n-1] == 'R'
+ && isdigit(buffer[1])
+ ) {
+ char *end;
+ unsigned long row, col;
- buffer[-1] = 0;
+ row = strtoul(buffer + 1, &end, 10);
+ if (*end != ';' || !isdigit(end[1]))
+ continue;
+ col = strtoul(end + 1, &end, 10);
+ if (*end != 'R')
+ continue;
+ if (row < 1 || col < 1 || (row | col) > 0x7fff)
+ continue;
- /* Pack into "1 <row15bits> <col16bits>" 32-bit sequence */
- c = (((-1 << 15) | row) << 16) | col;
- /* Return it in high-order word */
- return ((int64_t) c << 32) | (uint32_t)KEYCODE_CURSOR_POS;
+ buffer[-1] = 0;
+ /* Pack into "1 <row15bits> <col16bits>" 32-bit sequence */
+ col |= (((-1 << 15) | row) << 16);
+ /* Return it in high-order word */
+ return ((int64_t) col << 32) | (uint32_t)KEYCODE_CURSOR_POS;
+ }
}
+ got_all:
- ret:
- buffer[-1] = n;
- return c;
+ if (n <= 1) {
+ /* Alt-x is usually returned as ESC x.
+ * Report ESC, x is remembered for the next call.
+ */
+ buffer[-1] = n;
+ return 27;
+ }
+
+ /* We were doing "buffer[-1] = n; return c;" here, but this results
+ * in unknown key sequences being interpreted as ESC + garbage.
+ * This was not useful. Pretend there was no key pressed,
+ * go and wait for a new keypress:
+ */
+ buffer[-1] = 0;
+ goto start_over;
+}
+
+void FAST_FUNC read_key_ungets(char *buffer, const char *str, unsigned len)
+{
+ unsigned cur_len = (unsigned char)buffer[0];
+ if (len > KEYCODE_BUFFER_SIZE-1 - cur_len)
+ len = KEYCODE_BUFFER_SIZE-1 - cur_len;
+ memcpy(buffer + 1 + cur_len, str, len);
+ buffer[0] += len;
}
projects / platform / upstream / busybox.git / blobdiff