projects / deliverable / linux.git / blame
| Commit | Line | Data |
|---|---|---|
| 1da177e4 | 1 | /* |
| 1da177e4 LT |
2 | * Unified handling of special chars. |
| 3 | * | |
| a53c8fab | 4 | * Copyright IBM Corp. 2001 |
| 1da177e4 LT |
5 | * Author(s): Fritz Elfert <felfert@millenux.com> <elfert@de.ibm.com> |
| 6 | * | |
| 7 | */ | |
| 8 | ||
| 1da177e4 LT |
9 | #include <linux/stddef.h> |
| 10 | #include <asm/errno.h> | |
| 11 | #include <linux/sysrq.h> | |
| 12 | #include <linux/ctype.h> | |
| 13 | ||
| 14 | #include "ctrlchar.h" | |
| 15 | ||
| 16 | #ifdef CONFIG_MAGIC_SYSRQ | |
| 17 | static int ctrlchar_sysrq_key; | |
| 18 | ||
| 19 | static void | |
| e45ccc05 | 20 | ctrlchar_handle_sysrq(struct work_struct *work) |
| 1da177e4 | 21 | { |
| f335397d | 22 | handle_sysrq(ctrlchar_sysrq_key); |
| 1da177e4 LT |
23 | } |
| 24 | ||
| e45ccc05 | 25 | static DECLARE_WORK(ctrlchar_work, ctrlchar_handle_sysrq); |
| 1da177e4 LT |
26 | #endif |
| 27 | ||
| 28 | ||
| 29 | /** | |
| 30 | * Check for special chars at start of input. | |
| 31 | * | |
| 32 | * @param buf Console input buffer. | |
| 33 | * @param len Length of valid data in buffer. | |
| 34 | * @param tty The tty struct for this console. | |
| 35 | * @return CTRLCHAR_NONE, if nothing matched, | |
| 36 | * CTRLCHAR_SYSRQ, if sysrq was encountered | |
| 37 | * otherwise char to be inserted logically or'ed | |
| 38 | * with CTRLCHAR_CTRL | |
| 39 | */ | |
| 40 | unsigned int | |
| 41 | ctrlchar_handle(const unsigned char *buf, int len, struct tty_struct *tty) | |
| 42 | { | |
| 43 | if ((len < 2) || (len > 3)) | |
| 44 | return CTRLCHAR_NONE; | |
| 45 | ||
| 46 | /* hat is 0xb1 in codepage 037 (US etc.) and thus */ | |
| 47 | /* converted to 0x5e in ascii ('^') */ | |
| 48 | if ((buf[0] != '^') && (buf[0] != '\252')) | |
| 49 | return CTRLCHAR_NONE; | |
| 50 | ||
| 51 | #ifdef CONFIG_MAGIC_SYSRQ | |
| 52 | /* racy */ | |
| 53 | if (len == 3 && buf[1] == '-') { | |
| 54 | ctrlchar_sysrq_key = buf[2]; | |
| 1da177e4 LT |
55 | schedule_work(&ctrlchar_work); |
| 56 | return CTRLCHAR_SYSRQ; | |
| 57 | } | |
| 58 | #endif | |
| 59 | ||
| 60 | if (len != 2) | |
| 61 | return CTRLCHAR_NONE; | |
| 62 | ||
| 63 | switch (tolower(buf[1])) { | |
| 64 | case 'c': | |
| 65 | return INTR_CHAR(tty) | CTRLCHAR_CTRL; | |
| 66 | case 'd': | |
| 67 | return EOF_CHAR(tty) | CTRLCHAR_CTRL; | |
| 68 | case 'z': | |
| 69 | return SUSP_CHAR(tty) | CTRLCHAR_CTRL; | |
| 70 | } | |
| 71 | return CTRLCHAR_NONE; | |
| 72 | } |