io.c

eCos操作系统源码

            if (res == false) {
                do_idle(true);
                return _GETS_TIMEOUT;  // Input timed out
            }
        } else {
            mon_read_char(&c);
        }
        *eol = '\0';
        switch (c) {
#define CTRL(c) ((c)&0x1F)
#if CYGNUM_REDBOOT_CMD_LINE_EDITING != 0
        case CTRL('P'):
            // Fetch the previous line into the buffer
            if (_index >= 0) {
                // Erase the previous line [crude]
                while (ip != buf) {
                    mon_write_char('\b');
                    mon_write_char(' ');
                    mon_write_char('\b');
                    ip--;
                }
                strcpy(buf, _cl_lines[_index]);
                while (*ip) {
                    mon_write_char(*ip++);
                }
                eol = ip;
                // Move to previous line
                _index--;
                if (_index < 0) {
                    _index = _cl_max_index;
                }
            } else {
                mon_write_char(0x07);  // Audible bell on most devices
            }
            break;
        case CTRL('N'):
            // Fetch the next line into the buffer
            if (_index >= 0) {
                if (++_index > _cl_max_index) _index = 0;
                // Erase the previous line [crude]
                while (ip != buf) {
                    mon_write_char('\b');
                    mon_write_char(' ');
                    mon_write_char('\b');
                    ip--;
                }
                strcpy(buf, _cl_lines[_index]);
                while (*ip) {
                    mon_write_char(*ip++);
                }
                eol = ip;
            } else {
                mon_write_char(0x07);  // Audible bell on most devices
            }
            break;
        case CTRL('B'): 
            // Move insertion point backwards
            if (ip != buf) {
                mon_write_char('\b');
                ip--;
            }
            break;
        case CTRL('F'):
            // Move insertion point forwards
            if (ip != eol) {
                mon_write_char(*ip++);
            }
            break;
        case CTRL('E'):
            // Move insertion point to end of line
            while (ip != eol) {
                mon_write_char(*ip++);
            }
            break;
        case CTRL('A'):
            // Move insertion point to beginning of line
            if (ip != buf) {
                xp = ip;
                while (xp-- != buf) {
                    mon_write_char('\b');
                }
            }
            ip = buf;
            break;
        case CTRL('K'):
            // Kill to the end of line
            if (ip != eol) {
                xp = ip;
                while (xp++ != eol) {
                    mon_write_char(' ');
                }
                while (--xp != ip) {
                    mon_write_char('\b');
                }
                eol = ip;
            }
            break;
        case CTRL('D'):
            // Erase the character under the cursor
            if (ip != eol) {
                xp = ip;
                eol--;
                while (xp != eol) {
                    *xp = *(xp+1);
                    mon_write_char(*xp++);
                }
                mon_write_char(' ');  // Erases last character
                mon_write_char('\b');
                while (xp-- != ip) {
                    mon_write_char('\b');
                }
            }
            break;
#endif // CYGNUM_REDBOOT_CMD_LINE_EDITING
        case CTRL('C'): // ^C
            // Abort current input
            diag_printf("^C\n");
            *buf = '\0';  // Nothing useful in buffer
            return _GETS_CTRLC;
        case '\n':
        case '\r':
            // If previous character was the "other" end-of-line, ignore this one
            if (((c == '\n') && (last_ch == '\r')) ||
                ((c == '\r') && (last_ch == '\n'))) {
                c = '\0';
                break;
            }
            // End of line
	    if (console_echo) {
                mon_write_char('\r');
                mon_write_char('\n');
	    }
            last_ch = c;
#if CYGNUM_REDBOOT_CMD_LINE_EDITING != 0
            if (cmd_history) {
                // History handling - only when enabled
#ifdef CYGBLD_REDBOOT_CMD_LINE_HISTORY
		expand_history(buf);
#endif
		if (*buf != '\0') {
		    if (++_cl_index == _CL_NUM_LINES) _cl_index = 0;
		    if (_cl_index > _cl_max_index) _cl_max_index = _cl_index;
		    strcpy(_cl_lines[_cl_index], buf);
		}
            }
#endif
            return _GETS_OK;
        case '\b':
        case 0x7F:  // DEL
            if (ip != buf) {
#if CYGNUM_REDBOOT_CMD_LINE_EDITING != 0
                if (ip != eol) {
                    ip--;
                    mon_write_char('\b');
                    xp = ip;
                    while (xp != (eol-1)) {
                        *xp = *(xp+1);
                        mon_write_char(*xp++);
                    }
                    mon_write_char(' ');  // Erases last character
                    mon_write_char('\b');
                    while (xp-- != ip) {
                        mon_write_char('\b');
                    }
                } else {
                    if (console_echo) {
                        mon_write_char('\b');
                        mon_write_char(' ');
                        mon_write_char('\b');
                    }
                    ip--;
                }
                eol--;
#else
                if (console_echo) {
                    mon_write_char('\b');
                    mon_write_char(' ');
                    mon_write_char('\b');
                }
                ip--;
                eol--;
#endif
            }
            break;
#ifdef CYGDBG_HAL_DEBUG_GDB_INCLUDE_STUBS
        case '+': // fall through
        case '$':
            if (ip == buf || last_ch != '\\')
            {
                // Give up and try GDB protocol
                ungetDebugChar(c);  // Push back character so stubs will see it
                return _GETS_GDB;
            }
            if (last_ch == '\\') {
#if CYGNUM_REDBOOT_CMD_LINE_EDITING != 0
                if (ip == eol) {
                    // Just save \$ as $
                    eol = --ip;
                } else {
                    mon_write_char('\b');
                    *--ip = c;
                    mon_write_char(c);
                    break;
                }
#else
                ip--;  // Save \$ as $
#endif
            }
            // else fall through
#endif
        default:
#if CYGNUM_REDBOOT_CMD_LINE_EDITING != 0
            // If the insertion point is not at the end of line, make space for it
            if (ip != eol) {
                xp = eol;
                *++eol = '\0';
                while (xp != ip) {
                    *xp = *(xp-1);
                    xp--;
                }
            }
#endif
            if (console_echo) {
                mon_write_char(c);
            }
            if (ip == eol) {
                // Advance both pointers
                *ip++ = c;
                eol = ip;
#if CYGNUM_REDBOOT_CMD_LINE_EDITING != 0
            } else {
                // Just insert the character
                *ip++ = c;
                xp = ip;
                while (xp != eol) {
                    mon_write_char(*xp++);
                }
                while (xp-- != ip) {
                    mon_write_char('\b');
                }
#endif
            }
        }
        last_ch = c;
        if (ip == buf + buflen - 1) { // Buffer full
            *ip = '\0';
            return buflen;
        }
    }
}

int
_rb_gets(char *buf, int buflen, int timeout)
{
    *buf = '\0';  // Empty buffer
    return _rb_gets_preloaded(buf, buflen, timeout);
}

static bool
_verify_action(int timeout, char *fmt, va_list ap)
{
    char ans[8];
    int ret;
#ifdef CYGFUN_REDBOOT_BOOT_SCRIPT
    // Don't ask if we're executing a script
    if (script && *script)
        return 1;
#endif

    diag_vprintf(fmt, ap);
    diag_printf(" - continue (y/n)? ");
    if ((ret = _rb_gets(ans, sizeof(ans), timeout)) > 0) {
        return ((ans[0] == 'y') || (ans[0] == 'Y'));
    } else {
        if (ret == _GETS_TIMEOUT) {
            diag_printf(" ** Timed out!\n");
        }
        return 0;  // Timed out or ^C
    }
}

bool
verify_action(char *fmt, ...)
{
    va_list ap;

    va_start(ap, fmt);
    return _verify_action(0, fmt, ap);
}

bool
verify_action_with_timeout(int timeout, char *fmt, ...)
{
    va_list ap;

    va_start(ap, fmt);
    return _verify_action(timeout, fmt, ap);
}


#ifdef CYGBLD_REDBOOT_CMD_LINE_HISTORY
// parse for history index number. Return number or -1 if not
// an index number.
static int
parse_history_index(char *s)
{
    int val = 0;

    while ('0' <= *s && *s <= '9')
	val = (val * 10) + (*s++ - '0');

    if (*s)
	return -1;

    return val;
}

// Check input line to see if it needs history expansion. If so,
// try to find matching command and replace buffer as appropriate.
static void
expand_history(char *buf)
{
    int ncmds = _cl_max_index + 1;
    int i, index, len;

    if (buf[0] != '!' || buf[1] == '\0')
	return;

    if (ncmds > 0) {
	if (!strcmp(buf, "!!")) {
	    strcpy(buf, _cl_lines[_cl_index]);
	    return;
	}
	if ((index = parse_history_index(buf + 1)) >= 0) {
	    if (index <= _cl_max_index) {
		strcpy(buf, _cl_lines[index]);
		return;
	    }
	}
	len = strlen(buf + 1);
	for (i = 0, index = _cl_index; i < ncmds; i++) {
	    if (!strncmp(_cl_lines[index], buf+1, len)) {
		strcpy(buf, _cl_lines[index]);
		return;
	    }
	    if (--index < 0)
		index = _cl_max_index;
	}
    }

    diag_printf("%s: event not found\n", buf);
    *buf = '\0';
}

static void
do_history(int argc, char *argv[])
{
    int ncmds = _cl_max_index + 1;
    int i, index;

    if (_cl_index == _cl_max_index) {
	// history has not wrapped around
	for (i = 0; i < ncmds; i++)
	    diag_printf("%3d %s\n", i, _cl_lines[i]);
    } else {
	for (i = 0, index = _cl_index + 1; i < ncmds; i++) {
	    diag_printf("%3d %s\n", i, _cl_lines[index++]);
	    if (index > _cl_max_index)
		index = 0;
	}
    }
}

RedBoot_cmd("history", 
            "Display command history", 
            "",
            do_history
    );
#endif  // CYGBLD_REDBOOT_CMD_LINE_HISTORY