/* * Kernel Debugger Architecture Independent Console I/O handler * * This file is subject to the terms and conditions of the GNU General Public * License. See the file "COPYING" in the main directory of this archive * for more details. * * Copyright (c) 1999-2006 Silicon Graphics, Inc. All Rights Reserved. * Copyright (c) 2009 Wind River Systems, Inc. All Rights Reserved. */ #include <linux/types.h>#include <linux/ctype.h>#include <linux/kernel.h>#include <linux/init.h>#include <linux/kdev_t.h>#include <linux/console.h>#include <linux/string.h>#include <linux/sched.h>#include <linux/smp.h>#include <linux/nmi.h>#include <linux/delay.h>#include <linux/kgdb.h>#include <linux/kdb.h>#include <linux/kallsyms.h>#include "kdb_private.h" #define CMD_BUFLEN 256char kdb_prompt_str[CMD_BUFLEN]; int kdb_trap_printk;int kdb_printf_cpu = -1; static int kgdb_transition_check(char *buffer){ if (buffer[0] != '+' && buffer[0] != '$') { KDB_STATE_SET(KGDB_TRANS); kdb_printf("%s", buffer); } else { int slen = strlen(buffer); if (slen > 3 && buffer[slen - 3] == '#') { kdb_gdb_state_pass(buffer); strcpy(buffer, "kgdb"); KDB_STATE_SET(DOING_KGDB); return 1; } } return 0;} /** * kdb_handle_escape() - validity check on an accumulated escape sequence. * @buf: Accumulated escape characters to be examined. Note that buf * is not a string, it is an array of characters and need not be * nil terminated. * @sz: Number of accumulated escape characters. * * Return: -1 if the escape sequence is unwanted, 0 if it is incomplete, * otherwise it returns a mapped key value to pass to the upper layers. */static int kdb_handle_escape(char *buf, size_t sz){ char *lastkey = buf + sz - 1; switch (sz) { case 1: if (*lastkey == '\e') return 0; break; case 2: /* \e<something> */ if (*lastkey == '[') return 0; break; case 3: switch (*lastkey) { case 'A': /* \e[A, up arrow */ return 16; case 'B': /* \e[B, down arrow */ return 14; case 'C': /* \e[C, right arrow */ return 6; case 'D': /* \e[D, left arrow */ return 2; case '1': /* \e[<1,3,4>], may be home, del, end */ case '3': case '4': return 0; } break; case 4: if (*lastkey == '~') { switch (buf[2]) { case '1': /* \e[1~, home */ return 1; case '3': /* \e[3~, del */ return 4; case '4': /* \e[4~, end */ return 5; } } break; } return -1;} /** * kdb_getchar() - Read a single character from a kdb console (or consoles). * * Other than polling the various consoles that are currently enabled, * most of the work done in this function is dealing with escape sequences. * * An escape key could be the start of a vt100 control sequence such as \e[D * (left arrow) or it could be a character in its own right. The standard * method for detecting the difference is to wait for 2 seconds to see if there * are any other characters. kdb is complicated by the lack of a timer service * (interrupts are off), by multiple input sources. Escape sequence processing * has to be done as states in the polling loop. * * Return: The key pressed or a control code derived from an escape sequence. */char kdb_getchar(void){#define ESCAPE_UDELAY 1000#define ESCAPE_DELAY (2*1000000/ESCAPE_UDELAY) /* 2 seconds worth of udelays */ char buf[4]; /* longest vt100 escape sequence is 4 bytes */ char *pbuf = buf; int escape_delay = 0; get_char_func *f, *f_prev = NULL; int key; static bool last_char_was_cr; for (f = &kdb_poll_funcs[0]; ; ++f) { if (*f == NULL) { /* Reset NMI watchdog once per poll loop */ touch_nmi_watchdog(); f = &kdb_poll_funcs[0]; } key = (*f)(); if (key == -1) { if (escape_delay) { udelay(ESCAPE_UDELAY); if (--escape_delay == 0) return '\e'; } continue; } /* * The caller expects that newlines are either CR or LF. However * some terminals send _both_ CR and LF. Avoid having to handle * this in the caller by stripping the LF if we saw a CR right * before. */ if (last_char_was_cr && key == '\n') { last_char_was_cr = false; continue; } last_char_was_cr = (key == '\r'); /* * When the first character is received (or we get a change * input source) we set ourselves up to handle an escape * sequences (just in case). */ if (f_prev != f) { f_prev = f; pbuf = buf; escape_delay = ESCAPE_DELAY; } *pbuf++ = key; key = kdb_handle_escape(buf, pbuf - buf); if (key < 0) /* no escape sequence; return best character */ return buf[pbuf - buf == 2 ? 1 : 0]; if (key > 0) return key; } unreachable();} /** * kdb_position_cursor() - Place cursor in the correct horizontal position * @prompt: Nil-terminated string containing the prompt string * @buffer: Nil-terminated string containing the entire command line * @cp: Cursor position, pointer the character in buffer where the cursor * should be positioned. * * The cursor is positioned by sending a carriage-return and then printing * the content of the line until we reach the correct cursor position. * * There is some additional fine detail here. * * Firstly, even though kdb_printf() will correctly format zero-width fields * we want the second call to kdb_printf() to be conditional. That keeps things * a little cleaner when LOGGING=1. * * Secondly, we can't combine everything into one call to kdb_printf() since * that renders into a fixed length buffer and the combined print could result * in unwanted truncation. */static void kdb_position_cursor(char *prompt, char *buffer, char *cp){ kdb_printf("\r%s", prompt); if (cp > buffer) kdb_printf("%.*s", (int)(cp - buffer), buffer);} /* * kdb_read * * This function reads a string of characters, terminated by * a newline, or by reaching the end of the supplied buffer, * from the current kernel debugger console device. * Parameters: * buffer - Address of character buffer to receive input characters. * bufsize - size, in bytes, of the character buffer * Returns: * Returns a pointer to the buffer containing the received * character string. This string will be terminated by a * newline character. * Locking: * No locks are required to be held upon entry to this * function. It is not reentrant - it relies on the fact * that while kdb is running on only one "master debug" cpu. * Remarks: * The buffer size must be >= 2. */ static char *kdb_read(char *buffer, size_t bufsize){ char *cp = buffer; char *bufend = buffer+bufsize-2; /* Reserve space for newline * and null byte */ char *lastchar; char *p_tmp; char tmp; static char tmpbuffer[CMD_BUFLEN]; int len = strlen(buffer); int len_tmp; int tab = 0; int count; int i; int diag, dtab_count; int key, ret; diag = kdbgetintenv("DTABCOUNT", &dtab_count); if (diag) dtab_count = 30; if (len > 0) { cp += len; if (*(buffer+len-1) == '\n') cp--; } lastchar = cp; *cp = '\0'; kdb_printf("%s", buffer);poll_again: key = kdb_getchar(); if (key != 9) tab = 0; switch (key) { case 8: /* backspace */ if (cp > buffer) { memmove(cp-1, cp, lastchar - cp + 1); lastchar--; cp--; kdb_printf("\b%s ", cp); kdb_position_cursor(kdb_prompt_str, buffer, cp); } break; case 10: /* linefeed */ case 13: /* carriage return */ *lastchar++ = '\n'; *lastchar++ = '\0'; if (!KDB_STATE(KGDB_TRANS)) { KDB_STATE_SET(KGDB_TRANS); kdb_printf("%s", buffer); } kdb_printf("\n"); return buffer; case 4: /* Del */ if (cp < lastchar) { memmove(cp, cp+1, lastchar - cp); lastchar--; kdb_printf("%s ", cp); kdb_position_cursor(kdb_prompt_str, buffer, cp); } break; case 1: /* Home */ if (cp > buffer) { cp = buffer; kdb_position_cursor(kdb_prompt_str, buffer, cp); } break; case 5: /* End */ if (cp < lastchar) { kdb_printf("%s", cp); cp = lastchar; } break; case 2: /* Left */ if (cp > buffer) { kdb_printf("\b"); --cp; } break; case 14: /* Down */ case 16: /* Up */ kdb_printf("\r%*c\r", (int)(strlen(kdb_prompt_str) + (lastchar - buffer)), ' '); *lastchar = (char)key; *(lastchar+1) = '\0'; return lastchar; case 6: /* Right */ if (cp < lastchar) { kdb_printf("%c", *cp); ++cp; } break; case 9: /* Tab */ if (tab < 2) ++tab; tmp = *cp; *cp = '\0'; p_tmp = strrchr(buffer, ' '); p_tmp = (p_tmp ? p_tmp + 1 : buffer); strscpy(tmpbuffer, p_tmp, sizeof(tmpbuffer)); *cp = tmp; len = strlen(tmpbuffer); count = kallsyms_symbol_complete(tmpbuffer, sizeof(tmpbuffer)); if (tab == 2 && count > 0) { kdb_printf("\n%d symbols are found.", count); if (count > dtab_count) { count = dtab_count; kdb_printf(" But only first %d symbols will" " be printed.\nYou can change the" " environment variable DTABCOUNT.", count); } kdb_printf("\n"); for (i = 0; i < count; i++) { ret = kallsyms_symbol_next(tmpbuffer, i, sizeof(tmpbuffer)); if (WARN_ON(!ret)) break; if (ret != -E2BIG) kdb_printf("%s ", tmpbuffer); else kdb_printf("%s... ", tmpbuffer); tmpbuffer[len] = '\0'; } if (i >= dtab_count) kdb_printf("..."); kdb_printf("\n"); kdb_printf("%s", kdb_prompt_str); kdb_printf("%s", buffer); if (cp != lastchar) kdb_position_cursor(kdb_prompt_str, buffer, cp); } else if (tab != 2 && count > 0) { /* How many new characters do we want from tmpbuffer? */ len_tmp = strlen(tmpbuffer) - len; if (lastchar + len_tmp >= bufend) len_tmp = bufend - lastchar; if (len_tmp) { /* + 1 ensures the '\0' is memmove'd */ memmove(cp+len_tmp, cp, (lastchar-cp) + 1); memcpy(cp, tmpbuffer+len, len_tmp); kdb_printf("%s", cp); cp += len_tmp; lastchar += len_tmp; if (cp != lastchar) kdb_position_cursor(kdb_prompt_str, buffer, cp); } } kdb_nextline = 1; /* reset output line number */ break; default: if (key >= 32 && lastchar < bufend) { if (cp < lastchar) { memmove(cp+1, cp, lastchar - cp + 1); lastchar++; *cp = key; kdb_printf("%s", cp); ++cp; kdb_position_cursor(kdb_prompt_str, buffer, cp); } else { *++lastchar = '\0'; *cp++ = key; /* The kgdb transition check will hide * printed characters if we think that * kgdb is connecting, until the check * fails */ if (!KDB_STATE(KGDB_TRANS)) { if (kgdb_transition_check(buffer)) return buffer; } else { kdb_printf("%c", key); } } /* Special escape to kgdb */ if (lastchar - buffer >= 5 && strcmp(lastchar - 5, "$?#3f") == 0) { kdb_gdb_state_pass(lastchar - 5); strcpy(buffer, "kgdb"); KDB_STATE_SET(DOING_KGDB); return buffer; } if (lastchar - buffer >= 11 && strcmp(lastchar - 11, "$qSupported") == 0) { kdb_gdb_state_pass(lastchar - 11); strcpy(buffer, "kgdb"); KDB_STATE_SET(DOING_KGDB); return buffer; } } break; } goto poll_again;} /* * kdb_getstr * * Print the prompt string and read a command from the * input device. * * Parameters: * buffer Address of buffer to receive command * bufsize Size of buffer in bytes * prompt Pointer to string to use as prompt string * Returns: * Pointer to command buffer. * Locking: * None. * Remarks: * For SMP kernels, the processor number will be * substituted for %d, %x or %o in the prompt. */ char *kdb_getstr(char *buffer, size_t bufsize, const char *prompt){ if (prompt && kdb_prompt_str != prompt) strscpy(kdb_prompt_str, prompt, CMD_BUFLEN); kdb_printf("%s", kdb_prompt_str); kdb_nextline = 1; /* Prompt and input resets line number */ return kdb_read(buffer, bufsize);} /* * kdb_input_flush * * Get rid of any buffered console input. * * Parameters: * none * Returns: * nothing * Locking: * none * Remarks: * Call this function whenever you want to flush input. If there is any * outstanding input, it ignores all characters until there has been no * data for approximately 1ms. */ static void kdb_input_flush(void){ get_char_func *f; int res; int flush_delay = 1; while (flush_delay) { flush_delay--;empty: touch_nmi_watchdog(); for (f = &kdb_poll_funcs[0]; *f; ++f) { res = (*f)(); if (res != -1) { flush_delay = 1; goto empty; } } if (flush_delay) mdelay(1); }} /* * kdb_printfLines 1–500 of 902. Load more
/* * Kernel Debugger Architecture Independent Console I/O handler * * This file is subject to the terms and conditions of the GNU General Public * License. See the file "COPYING" in the main directory of this archive * for more details. * * Copyright (c) 1999-2006 Silicon Graphics, Inc. All Rights Reserved. * Copyright (c) 2009 Wind River Systems, Inc. All Rights Reserved. */ #include <linux/types.h> #include <linux/ctype.h> #include <linux/kernel.h> #include <linux/init.h> #include <linux/kdev_t.h> #include <linux/console.h> #include <linux/string.h> #include <linux/sched.h> #include <linux/smp.h> #include <linux/nmi.h> #include <linux/delay.h> #include <linux/kgdb.h> #include <linux/kdb.h> #include <linux/kallsyms.h> #include "kdb_private.h" #define CMD_BUFLEN 256 char kdb_prompt_str[CMD_BUFLEN]; int kdb_trap_printk; int kdb_printf_cpu = -1; static int kgdb_transition_check(char *buffer) { if (buffer[0] != '+' && buffer[0] != '$') { KDB_STATE_SET(KGDB_TRANS); kdb_printf("%s", buffer); } else { int slen = strlen(buffer); if (slen > 3 && buffer[slen - 3] == '#') { kdb_gdb_state_pass(buffer); strcpy(buffer, "kgdb"); KDB_STATE_SET(DOING_KGDB); return 1; } } return 0; } /** * kdb_handle_escape() - validity check on an accumulated escape sequence. * @buf: Accumulated escape characters to be examined. Note that buf * is not a string, it is an array of characters and need not be * nil terminated. * @sz: Number of accumulated escape characters. * * Return: -1 if the escape sequence is unwanted, 0 if it is incomplete, * otherwise it returns a mapped key value to pass to the upper layers. */ static int kdb_handle_escape(char *buf, size_t sz) { char *lastkey = buf + sz - 1; switch (sz) { case 1: if (*lastkey == '\e') return 0; break; case 2: /* \e<something> */ if (*lastkey == '[') return 0; break; case 3: switch (*lastkey) { case 'A': /* \e[A, up arrow */ return 16; case 'B': /* \e[B, down arrow */ return 14; case 'C': /* \e[C, right arrow */ return 6; case 'D': /* \e[D, left arrow */ return 2; case '1': /* \e[<1,3,4>], may be home, del, end */ case '3': case '4': return 0; } break; case 4: if (*lastkey == '~') { switch (buf[2]) { case '1': /* \e[1~, home */ return 1; case '3': /* \e[3~, del */ return 4; case '4': /* \e[4~, end */ return 5; } } break; } return -1; } /** * kdb_getchar() - Read a single character from a kdb console (or consoles). * * Other than polling the various consoles that are currently enabled, * most of the work done in this function is dealing with escape sequences. * * An escape key could be the start of a vt100 control sequence such as \e[D * (left arrow) or it could be a character in its own right. The standard * method for detecting the difference is to wait for 2 seconds to see if there * are any other characters. kdb is complicated by the lack of a timer service * (interrupts are off), by multiple input sources. Escape sequence processing * has to be done as states in the polling loop. * * Return: The key pressed or a control code derived from an escape sequence. */ char kdb_getchar(void) { #define ESCAPE_UDELAY 1000 #define ESCAPE_DELAY (2*1000000/ESCAPE_UDELAY) /* 2 seconds worth of udelays */ char buf[4]; /* longest vt100 escape sequence is 4 bytes */ char *pbuf = buf; int escape_delay = 0; get_char_func *f, *f_prev = NULL; int key; static bool last_char_was_cr; for (f = &kdb_poll_funcs[0]; ; ++f) { if (*f == NULL) { /* Reset NMI watchdog once per poll loop */ touch_nmi_watchdog(); f = &kdb_poll_funcs[0]; } key = (*f)(); if (key == -1) { if (escape_delay) { udelay(ESCAPE_UDELAY); if (--escape_delay == 0) return '\e'; } continue; } /* * The caller expects that newlines are either CR or LF. However * some terminals send _both_ CR and LF. Avoid having to handle * this in the caller by stripping the LF if we saw a CR right * before. */ if (last_char_was_cr && key == '\n') { last_char_was_cr = false; continue; } last_char_was_cr = (key == '\r'); /* * When the first character is received (or we get a change * input source) we set ourselves up to handle an escape * sequences (just in case). */ if (f_prev != f) { f_prev = f; pbuf = buf; escape_delay = ESCAPE_DELAY; } *pbuf++ = key; key = kdb_handle_escape(buf, pbuf - buf); if (key < 0) /* no escape sequence; return best character */ return buf[pbuf - buf == 2 ? 1 : 0]; if (key > 0) return key; } unreachable(); } /** * kdb_position_cursor() - Place cursor in the correct horizontal position * @prompt: Nil-terminated string containing the prompt string * @buffer: Nil-terminated string containing the entire command line * @cp: Cursor position, pointer the character in buffer where the cursor * should be positioned. * * The cursor is positioned by sending a carriage-return and then printing * the content of the line until we reach the correct cursor position. * * There is some additional fine detail here. * * Firstly, even though kdb_printf() will correctly format zero-width fields * we want the second call to kdb_printf() to be conditional. That keeps things * a little cleaner when LOGGING=1. * * Secondly, we can't combine everything into one call to kdb_printf() since * that renders into a fixed length buffer and the combined print could result * in unwanted truncation. */ static void kdb_position_cursor(char *prompt, char *buffer, char *cp) { kdb_printf("\r%s", prompt); if (cp > buffer) kdb_printf("%.*s", (int)(cp - buffer), buffer); } /* * kdb_read * * This function reads a string of characters, terminated by * a newline, or by reaching the end of the supplied buffer, * from the current kernel debugger console device. * Parameters: * buffer - Address of character buffer to receive input characters. * bufsize - size, in bytes, of the character buffer * Returns: * Returns a pointer to the buffer containing the received * character string. This string will be terminated by a * newline character. * Locking: * No locks are required to be held upon entry to this * function. It is not reentrant - it relies on the fact * that while kdb is running on only one "master debug" cpu. * Remarks: * The buffer size must be >= 2. */ static char *kdb_read(char *buffer, size_t bufsize) { char *cp = buffer; char *bufend = buffer+bufsize-2; /* Reserve space for newline * and null byte */ char *lastchar; char *p_tmp; char tmp; static char tmpbuffer[CMD_BUFLEN]; int len = strlen(buffer); int len_tmp; int tab = 0; int count; int i; int diag, dtab_count; int key, ret; diag = kdbgetintenv("DTABCOUNT", &dtab_count); if (diag) dtab_count = 30; if (len > 0) { cp += len; if (*(buffer+len-1) == '\n') cp--; } lastchar = cp; *cp = '\0'; kdb_printf("%s", buffer); poll_again: key = kdb_getchar(); if (key != 9) tab = 0; switch (key) { case 8: /* backspace */ if (cp > buffer) { memmove(cp-1, cp, lastchar - cp + 1); lastchar--; cp--; kdb_printf("\b%s ", cp); kdb_position_cursor(kdb_prompt_str, buffer, cp); } break; case 10: /* linefeed */ case 13: /* carriage return */ *lastchar++ = '\n'; *lastchar++ = '\0'; if (!KDB_STATE(KGDB_TRANS)) { KDB_STATE_SET(KGDB_TRANS); kdb_printf("%s", buffer); } kdb_printf("\n"); return buffer; case 4: /* Del */ if (cp < lastchar) { memmove(cp, cp+1, lastchar - cp); lastchar--; kdb_printf("%s ", cp); kdb_position_cursor(kdb_prompt_str, buffer, cp); } break; case 1: /* Home */ if (cp > buffer) { cp = buffer; kdb_position_cursor(kdb_prompt_str, buffer, cp); } break; case 5: /* End */ if (cp < lastchar) { kdb_printf("%s", cp); cp = lastchar; } break; case 2: /* Left */ if (cp > buffer) { kdb_printf("\b"); --cp; } break; case 14: /* Down */ case 16: /* Up */ kdb_printf("\r%*c\r", (int)(strlen(kdb_prompt_str) + (lastchar - buffer)), ' '); *lastchar = (char)key; *(lastchar+1) = '\0'; return lastchar; case 6: /* Right */ if (cp < lastchar) { kdb_printf("%c", *cp); ++cp; } break; case 9: /* Tab */ if (tab < 2) ++tab; tmp = *cp; *cp = '\0'; p_tmp = strrchr(buffer, ' '); p_tmp = (p_tmp ? p_tmp + 1 : buffer); strscpy(tmpbuffer, p_tmp, sizeof(tmpbuffer)); *cp = tmp; len = strlen(tmpbuffer); count = kallsyms_symbol_complete(tmpbuffer, sizeof(tmpbuffer)); if (tab == 2 && count > 0) { kdb_printf("\n%d symbols are found.", count); if (count > dtab_count) { count = dtab_count; kdb_printf(" But only first %d symbols will" " be printed.\nYou can change the" " environment variable DTABCOUNT.", count); } kdb_printf("\n"); for (i = 0; i < count; i++) { ret = kallsyms_symbol_next(tmpbuffer, i, sizeof(tmpbuffer)); if (WARN_ON(!ret)) break; if (ret != -E2BIG) kdb_printf("%s ", tmpbuffer); else kdb_printf("%s... ", tmpbuffer); tmpbuffer[len] = '\0'; } if (i >= dtab_count) kdb_printf("..."); kdb_printf("\n"); kdb_printf("%s", kdb_prompt_str); kdb_printf("%s", buffer); if (cp != lastchar) kdb_position_cursor(kdb_prompt_str, buffer, cp); } else if (tab != 2 && count > 0) { /* How many new characters do we want from tmpbuffer? */ len_tmp = strlen(tmpbuffer) - len; if (lastchar + len_tmp >= bufend) len_tmp = bufend - lastchar; if (len_tmp) { /* + 1 ensures the '\0' is memmove'd */ memmove(cp+len_tmp, cp, (lastchar-cp) + 1); memcpy(cp, tmpbuffer+len, len_tmp); kdb_printf("%s", cp); cp += len_tmp; lastchar += len_tmp; if (cp != lastchar) kdb_position_cursor(kdb_prompt_str, buffer, cp); } } kdb_nextline = 1; /* reset output line number */ break; default: if (key >= 32 && lastchar < bufend) { if (cp < lastchar) { memmove(cp+1, cp, lastchar - cp + 1); lastchar++; *cp = key; kdb_printf("%s", cp); ++cp; kdb_position_cursor(kdb_prompt_str, buffer, cp); } else { *++lastchar = '\0'; *cp++ = key; /* The kgdb transition check will hide * printed characters if we think that * kgdb is connecting, until the check * fails */ if (!KDB_STATE(KGDB_TRANS)) { if (kgdb_transition_check(buffer)) return buffer; } else { kdb_printf("%c", key); } } /* Special escape to kgdb */ if (lastchar - buffer >= 5 && strcmp(lastchar - 5, "$?#3f") == 0) { kdb_gdb_state_pass(lastchar - 5); strcpy(buffer, "kgdb"); KDB_STATE_SET(DOING_KGDB); return buffer; } if (lastchar - buffer >= 11 && strcmp(lastchar - 11, "$qSupported") == 0) { kdb_gdb_state_pass(lastchar - 11); strcpy(buffer, "kgdb"); KDB_STATE_SET(DOING_KGDB); return buffer; } } break; } goto poll_again; } /* * kdb_getstr * * Print the prompt string and read a command from the * input device. * * Parameters: * buffer Address of buffer to receive command * bufsize Size of buffer in bytes * prompt Pointer to string to use as prompt string * Returns: * Pointer to command buffer. * Locking: * None. * Remarks: * For SMP kernels, the processor number will be * substituted for %d, %x or %o in the prompt. */ char *kdb_getstr(char *buffer, size_t bufsize, const char *prompt) { if (prompt && kdb_prompt_str != prompt) strscpy(kdb_prompt_str, prompt, CMD_BUFLEN); kdb_printf("%s", kdb_prompt_str); kdb_nextline = 1; /* Prompt and input resets line number */ return kdb_read(buffer, bufsize); } /* * kdb_input_flush * * Get rid of any buffered console input. * * Parameters: * none * Returns: * nothing * Locking: * none * Remarks: * Call this function whenever you want to flush input. If there is any * outstanding input, it ignores all characters until there has been no * data for approximately 1ms. */ static void kdb_input_flush(void) { get_char_func *f; int res; int flush_delay = 1; while (flush_delay) { flush_delay--; empty: touch_nmi_watchdog(); for (f = &kdb_poll_funcs[0]; *f; ++f) { res = (*f)(); if (res != -1) { flush_delay = 1; goto empty; } } if (flush_delay) mdelay(1); } } /* * kdb_printf