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 | |
| ab7373bf | 17 | static struct sysrq_work ctrlchar_sysrq; |
| 1da177e4 LT |
18 | |
| 19 | static void | |
| e45ccc05 | 20 | ctrlchar_handle_sysrq(struct work_struct *work) |
| 1da177e4 | 21 | { |
| ab7373bf HB |
22 | struct sysrq_work *sysrq = container_of(work, struct sysrq_work, work); |
| 23 | ||
| 24 | handle_sysrq(sysrq->key); | |
| 1da177e4 LT |
25 | } |
| 26 | ||
| ab7373bf HB |
27 | void schedule_sysrq_work(struct sysrq_work *sw) |
| 28 | { | |
| 29 | INIT_WORK(&sw->work, ctrlchar_handle_sysrq); | |
| 30 | schedule_work(&sw->work); | |
| 31 | } | |
| 1da177e4 LT |
32 | #endif |
| 33 | ||
| 34 | ||
| 35 | /** | |
| 36 | * Check for special chars at start of input. | |
| 37 | * | |
| 38 | * @param buf Console input buffer. | |
| 39 | * @param len Length of valid data in buffer. | |
| 40 | * @param tty The tty struct for this console. | |
| 41 | * @return CTRLCHAR_NONE, if nothing matched, | |
| 42 | * CTRLCHAR_SYSRQ, if sysrq was encountered | |
| 43 | * otherwise char to be inserted logically or'ed | |
| 44 | * with CTRLCHAR_CTRL | |
| 45 | */ | |
| 46 | unsigned int | |
| 47 | ctrlchar_handle(const unsigned char *buf, int len, struct tty_struct *tty) | |
| 48 | { | |
| 49 | if ((len < 2) || (len > 3)) | |
| 50 | return CTRLCHAR_NONE; | |
| 51 | ||
| 52 | /* hat is 0xb1 in codepage 037 (US etc.) and thus */ | |
| 53 | /* converted to 0x5e in ascii ('^') */ | |
| 54 | if ((buf[0] != '^') && (buf[0] != '\252')) | |
| 55 | return CTRLCHAR_NONE; | |
| 56 | ||
| 57 | #ifdef CONFIG_MAGIC_SYSRQ | |
| 58 | /* racy */ | |
| 59 | if (len == 3 && buf[1] == '-') { | |
| ab7373bf HB |
60 | ctrlchar_sysrq.key = buf[2]; |
| 61 | schedule_sysrq_work(&ctrlchar_sysrq); | |
| 1da177e4 LT |
62 | return CTRLCHAR_SYSRQ; |
| 63 | } | |
| 64 | #endif | |
| 65 | ||
| 66 | if (len != 2) | |
| 67 | return CTRLCHAR_NONE; | |
| 68 | ||
| 69 | switch (tolower(buf[1])) { | |
| 70 | case 'c': | |
| 71 | return INTR_CHAR(tty) | CTRLCHAR_CTRL; | |
| 72 | case 'd': | |
| 73 | return EOF_CHAR(tty) | CTRLCHAR_CTRL; | |
| 74 | case 'z': | |
| 75 | return SUSP_CHAR(tty) | CTRLCHAR_CTRL; | |
| 76 | } | |
| 77 | return CTRLCHAR_NONE; | |
| 78 | } |