projects / linux.git / blame
| Commit | Line | Data |
|---|---|---|
| 1da177e4 LT |
1 | /* |
| 2 | * drivers/s390/char/ctrlchar.c | |
| 3 | * Unified handling of special chars. | |
| 4 | * | |
| 5 | * Copyright (C) 2001 IBM Deutschland Entwicklung GmbH, IBM Corporation | |
| 6 | * Author(s): Fritz Elfert <[email protected]> <[email protected]> | |
| 7 | * | |
| 8 | */ | |
| 9 | ||
| 1da177e4 LT |
10 | #include <linux/stddef.h> |
| 11 | #include <asm/errno.h> | |
| 12 | #include <linux/sysrq.h> | |
| 13 | #include <linux/ctype.h> | |
| 14 | ||
| 15 | #include "ctrlchar.h" | |
| 16 | ||
| 17 | #ifdef CONFIG_MAGIC_SYSRQ | |
| 18 | static int ctrlchar_sysrq_key; | |
| 19 | ||
| 20 | static void | |
| e45ccc05 | 21 | ctrlchar_handle_sysrq(struct work_struct *work) |
| 1da177e4 | 22 | { |
| f335397d | 23 | handle_sysrq(ctrlchar_sysrq_key); |
| 1da177e4 LT |
24 | } |
| 25 | ||
| e45ccc05 | 26 | static DECLARE_WORK(ctrlchar_work, ctrlchar_handle_sysrq); |
| 1da177e4 LT |
27 | #endif |
| 28 | ||
| 29 | ||
| 30 | /** | |
| 31 | * Check for special chars at start of input. | |
| 32 | * | |
| 33 | * @param buf Console input buffer. | |
| 34 | * @param len Length of valid data in buffer. | |
| 35 | * @param tty The tty struct for this console. | |
| 36 | * @return CTRLCHAR_NONE, if nothing matched, | |
| 37 | * CTRLCHAR_SYSRQ, if sysrq was encountered | |
| 38 | * otherwise char to be inserted logically or'ed | |
| 39 | * with CTRLCHAR_CTRL | |
| 40 | */ | |
| 41 | unsigned int | |
| 42 | ctrlchar_handle(const unsigned char *buf, int len, struct tty_struct *tty) | |
| 43 | { | |
| 44 | if ((len < 2) || (len > 3)) | |
| 45 | return CTRLCHAR_NONE; | |
| 46 | ||
| 47 | /* hat is 0xb1 in codepage 037 (US etc.) and thus */ | |
| 48 | /* converted to 0x5e in ascii ('^') */ | |
| 49 | if ((buf[0] != '^') && (buf[0] != '\252')) | |
| 50 | return CTRLCHAR_NONE; | |
| 51 | ||
| 52 | #ifdef CONFIG_MAGIC_SYSRQ | |
| 53 | /* racy */ | |
| 54 | if (len == 3 && buf[1] == '-') { | |
| 55 | ctrlchar_sysrq_key = buf[2]; | |
| 1da177e4 LT |
56 | schedule_work(&ctrlchar_work); |
| 57 | return CTRLCHAR_SYSRQ; | |
| 58 | } | |
| 59 | #endif | |
| 60 | ||
| 61 | if (len != 2) | |
| 62 | return CTRLCHAR_NONE; | |
| 63 | ||
| 64 | switch (tolower(buf[1])) { | |
| 65 | case 'c': | |
| 66 | return INTR_CHAR(tty) | CTRLCHAR_CTRL; | |
| 67 | case 'd': | |
| 68 | return EOF_CHAR(tty) | CTRLCHAR_CTRL; | |
| 69 | case 'z': | |
| 70 | return SUSP_CHAR(tty) | CTRLCHAR_CTRL; | |
| 71 | } | |
| 72 | return CTRLCHAR_NONE; | |
| 73 | } |