Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright (C) 1996 Paul Mackerras. |
| 3 | * |
| 4 | * This program is free software; you can redistribute it and/or |
| 5 | * modify it under the terms of the GNU General Public License |
| 6 | * as published by the Free Software Foundation; either version |
| 7 | * 2 of the License, or (at your option) any later version. |
| 8 | */ |
| 9 | #include <linux/config.h> |
| 10 | #include <linux/string.h> |
| 11 | #include <linux/kernel.h> |
| 12 | #include <linux/errno.h> |
| 13 | #include <linux/sysrq.h> |
| 14 | #include <linux/init.h> |
| 15 | #include <asm/machdep.h> |
| 16 | #include <asm/io.h> |
| 17 | #include <asm/page.h> |
| 18 | #include <asm/prom.h> |
| 19 | #include <asm/processor.h> |
| 20 | #include <asm/udbg.h> |
| 21 | #include <asm/system.h> |
| 22 | #include "nonstdio.h" |
| 23 | |
| 24 | #ifdef CONFIG_MAGIC_SYSRQ |
| 25 | |
| 26 | static void sysrq_handle_xmon(int key, struct pt_regs *pt_regs, |
| 27 | struct tty_struct *tty) |
| 28 | { |
| 29 | /* ensure xmon is enabled */ |
| 30 | xmon_init(); |
| 31 | debugger(pt_regs); |
| 32 | } |
| 33 | |
| 34 | static struct sysrq_key_op sysrq_xmon_op = |
| 35 | { |
| 36 | .handler = sysrq_handle_xmon, |
| 37 | .help_msg = "Xmon", |
| 38 | .action_msg = "Entering xmon", |
| 39 | }; |
| 40 | |
| 41 | static int __init setup_xmon_sysrq(void) |
| 42 | { |
| 43 | register_sysrq_key('x', &sysrq_xmon_op); |
| 44 | return 0; |
| 45 | } |
| 46 | __initcall(setup_xmon_sysrq); |
| 47 | #endif /* CONFIG_MAGIC_SYSRQ */ |
| 48 | |
| 49 | int |
| 50 | xmon_write(void *handle, void *ptr, int nb) |
| 51 | { |
| 52 | return udbg_write(ptr, nb); |
| 53 | } |
| 54 | |
| 55 | int |
| 56 | xmon_read(void *handle, void *ptr, int nb) |
| 57 | { |
| 58 | return udbg_read(ptr, nb); |
| 59 | } |
| 60 | |
| 61 | int |
| 62 | xmon_read_poll(void) |
| 63 | { |
| 64 | return udbg_getc_poll(); |
| 65 | } |
| 66 | |
| 67 | FILE *xmon_stdin; |
| 68 | FILE *xmon_stdout; |
| 69 | |
| 70 | int |
| 71 | xmon_putc(int c, void *f) |
| 72 | { |
| 73 | char ch = c; |
| 74 | |
| 75 | if (c == '\n') |
| 76 | xmon_putc('\r', f); |
| 77 | return xmon_write(f, &ch, 1) == 1? c: -1; |
| 78 | } |
| 79 | |
| 80 | int |
| 81 | xmon_putchar(int c) |
| 82 | { |
| 83 | return xmon_putc(c, xmon_stdout); |
| 84 | } |
| 85 | |
| 86 | int |
| 87 | xmon_fputs(char *str, void *f) |
| 88 | { |
| 89 | int n = strlen(str); |
| 90 | |
| 91 | return xmon_write(f, str, n) == n? 0: -1; |
| 92 | } |
| 93 | |
| 94 | int |
| 95 | xmon_readchar(void) |
| 96 | { |
| 97 | char ch; |
| 98 | |
| 99 | for (;;) { |
| 100 | switch (xmon_read(xmon_stdin, &ch, 1)) { |
| 101 | case 1: |
| 102 | return ch; |
| 103 | case -1: |
| 104 | xmon_printf("read(stdin) returned -1\r\n", 0, 0); |
| 105 | return -1; |
| 106 | } |
| 107 | } |
| 108 | } |
| 109 | |
| 110 | static char line[256]; |
| 111 | static char *lineptr; |
| 112 | static int lineleft; |
| 113 | |
| 114 | int |
| 115 | xmon_getchar(void) |
| 116 | { |
| 117 | int c; |
| 118 | |
| 119 | if (lineleft == 0) { |
| 120 | lineptr = line; |
| 121 | for (;;) { |
| 122 | c = xmon_readchar(); |
| 123 | if (c == -1 || c == 4) |
| 124 | break; |
| 125 | if (c == '\r' || c == '\n') { |
| 126 | *lineptr++ = '\n'; |
| 127 | xmon_putchar('\n'); |
| 128 | break; |
| 129 | } |
| 130 | switch (c) { |
| 131 | case 0177: |
| 132 | case '\b': |
| 133 | if (lineptr > line) { |
| 134 | xmon_putchar('\b'); |
| 135 | xmon_putchar(' '); |
| 136 | xmon_putchar('\b'); |
| 137 | --lineptr; |
| 138 | } |
| 139 | break; |
| 140 | case 'U' & 0x1F: |
| 141 | while (lineptr > line) { |
| 142 | xmon_putchar('\b'); |
| 143 | xmon_putchar(' '); |
| 144 | xmon_putchar('\b'); |
| 145 | --lineptr; |
| 146 | } |
| 147 | break; |
| 148 | default: |
| 149 | if (lineptr >= &line[sizeof(line) - 1]) |
| 150 | xmon_putchar('\a'); |
| 151 | else { |
| 152 | xmon_putchar(c); |
| 153 | *lineptr++ = c; |
| 154 | } |
| 155 | } |
| 156 | } |
| 157 | lineleft = lineptr - line; |
| 158 | lineptr = line; |
| 159 | } |
| 160 | if (lineleft == 0) |
| 161 | return -1; |
| 162 | --lineleft; |
| 163 | return *lineptr++; |
| 164 | } |
| 165 | |
| 166 | char * |
| 167 | xmon_fgets(char *str, int nb, void *f) |
| 168 | { |
| 169 | char *p; |
| 170 | int c; |
| 171 | |
| 172 | for (p = str; p < str + nb - 1; ) { |
| 173 | c = xmon_getchar(); |
| 174 | if (c == -1) { |
| 175 | if (p == str) |
| 176 | return NULL; |
| 177 | break; |
| 178 | } |
| 179 | *p++ = c; |
| 180 | if (c == '\n') |
| 181 | break; |
| 182 | } |
| 183 | *p = 0; |
| 184 | return str; |
| 185 | } |