/* * 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 #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "kdb_private.h" #define CMD_BUFLEN 256 char kdb_prompt_str[CMD_BUFLEN]; int kdb_trap_printk; 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; } static int kdb_read_get_key(char *buffer, size_t bufsize) { #define ESCAPE_UDELAY 1000 #define ESCAPE_DELAY (2*1000000/ESCAPE_UDELAY) /* 2 seconds worth of udelays */ char escape_data[5]; /* longest vt100 escape sequence is 4 bytes */ char *ped = escape_data; int escape_delay = 0; get_char_func *f, *f_escape = NULL; int key; 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]; } if (escape_delay == 2) { *ped = '\0'; ped = escape_data; --escape_delay; } if (escape_delay == 1) { key = *ped++; if (!*ped) --escape_delay; break; } key = (*f)(); if (key == -1) { if (escape_delay) { udelay(ESCAPE_UDELAY); --escape_delay; } continue; } if (bufsize <= 2) { if (key == '\r') key = '\n'; *buffer++ = key; *buffer = '\0'; return -1; } if (escape_delay == 0 && key == '\e') { escape_delay = ESCAPE_DELAY; ped = escape_data; f_escape = f; } if (escape_delay) { *ped++ = key; if (f_escape != f) { escape_delay = 2; continue; } if (ped - escape_data == 1) { /* \e */ continue; } else if (ped - escape_data == 2) { /* \e */ if (key != '[') escape_delay = 2; continue; } else if (ped - escape_data == 3) { /* \e[ */ int mapkey = 0; switch (key) { case 'A': /* \e[A, up arrow */ mapkey = 16; break; case 'B': /* \e[B, down arrow */ mapkey = 14; break; case 'C': /* \e[C, right arrow */ mapkey = 6; break; case 'D': /* \e[D, left arrow */ mapkey = 2; break; case '1': /* dropthrough */ case '3': /* dropthrough */ /* \e[<1,3,4>], may be home, del, end */ case '4': mapkey = -1; break; } if (mapkey != -1) { if (mapkey > 0) { escape_data[0] = mapkey; escape_data[1] = '\0'; } escape_delay = 2; } continue; } else if (ped - escape_data == 4) { /* \e[<1,3,4> */ int mapkey = 0; if (key == '~') { switch (escape_data[2]) { case '1': /* \e[1~, home */ mapkey = 1; break; case '3': /* \e[3~, del */ mapkey = 4; break; case '4': /* \e[4~, end */ mapkey = 5; break; } } if (mapkey > 0) { escape_data[0] = mapkey; escape_data[1] = '\0'; } escape_delay = 2; continue; } } break; /* A key to process */ } return key; } /* * 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. A buffer size of 2 means that the caller only * wants a single key. * * 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 and by the need to sometimes * return after just one key. Escape sequence processing has to be done as * states in the polling loop. */ 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; 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_read_get_key(buffer, bufsize); if (key == -1) return buffer; if (key != 9) tab = 0; switch (key) { case 8: /* backspace */ if (cp > buffer) { if (cp < lastchar) { memcpy(tmpbuffer, cp, lastchar - cp); memcpy(cp-1, tmpbuffer, lastchar - cp); } *(--lastchar) = '\0'; --cp; kdb_printf("\b%s \r", cp); tmp = *cp; *cp = '\0'; kdb_printf(kdb_prompt_str); kdb_printf("%s", buffer); *cp = tmp; } break; case 13: /* enter */ *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) { memcpy(tmpbuffer, cp+1, lastchar - cp - 1); memcpy(cp, tmpbuffer, lastchar - cp - 1); *(--lastchar) = '\0'; kdb_printf("%s \r", cp); tmp = *cp; *cp = '\0'; kdb_printf(kdb_prompt_str); kdb_printf("%s", buffer); *cp = tmp; } break; case 1: /* Home */ if (cp > buffer) { kdb_printf("\r"); kdb_printf(kdb_prompt_str); cp = buffer; } 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 */ memset(tmpbuffer, ' ', strlen(kdb_prompt_str) + (lastchar-buffer)); *(tmpbuffer+strlen(kdb_prompt_str) + (lastchar-buffer)) = '\0'; kdb_printf("\r%s\r", tmpbuffer); *lastchar = (char)key; *(lastchar+1) = '\0'; return lastchar; case 6: /* Right */ if (cp < lastchar) { kdb_printf("%c", *cp); ++cp; } break; case 16: /* Up */ memset(tmpbuffer, ' ', strlen(kdb_prompt_str) + (lastchar-buffer)); *(tmpbuffer+strlen(kdb_prompt_str) + (lastchar-buffer)) = '\0'; kdb_printf("\r%s\r", tmpbuffer); *lastchar = (char)key; *(lastchar+1) = '\0'; return lastchar; case 9: /* Tab */ if (tab < 2) ++tab; p_tmp = buffer; while (*p_tmp == ' ') p_tmp++; if (p_tmp > cp) break; memcpy(tmpbuffer, p_tmp, cp-p_tmp); *(tmpbuffer + (cp-p_tmp)) = '\0'; p_tmp = strrchr(tmpbuffer, ' '); if (p_tmp) ++p_tmp; else p_tmp = tmpbuffer; len = strlen(p_tmp); count = kallsyms_symbol_complete(p_tmp, sizeof(tmpbuffer) - (p_tmp - 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++) { if (kallsyms_symbol_next(p_tmp, i) < 0) break; kdb_printf("%s ", p_tmp); *(p_tmp + len) = '\0'; } if (i >= dtab_count) kdb_printf("..."); kdb_printf("\n"); kdb_printf(kdb_prompt_str); kdb_printf("%s", buffer); } else if (tab != 2 && count > 0) { len_tmp = strlen(p_tmp); strncpy(p_tmp+len_tmp, cp, lastchar-cp+1); len_tmp = strlen(p_tmp); strncpy(cp, p_tmp+len, len_tmp-len + 1); len = len_tmp - len; kdb_printf("%s", cp); cp += len; lastchar += len; } kdb_nextline = 1; /* reset output line number */ break; default: if (key >= 32 && lastchar < bufend) { if (cp < lastchar) { memcpy(tmpbuffer, cp, lastchar - cp); memcpy(cp+1, tmpbuffer, lastchar - cp); *++lastchar = '\0'; *cp = key; kdb_printf("%s\r", cp); ++cp; tmp = *cp; *cp = '\0'; kdb_printf(kdb_prompt_str); kdb_printf("%s", buffer); *cp = tmp; } 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, char *prompt) { if (prompt && kdb_prompt_str != prompt) strncpy(kdb_prompt_str, prompt, CMD_BUFLEN); kdb_printf(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 * * Print a string to the output device(s). * * Parameters: * printf-like format and optional args. * Returns: * 0 * Locking: * None. * Remarks: * use 'kdbcons->write()' to avoid polluting 'log_buf' with * kdb output. * * If the user is doing a cmd args | grep srch * then kdb_grepping_flag is set. * In that case we need to accumulate full lines (ending in \n) before * searching for the pattern. */ static char kdb_buffer[256]; /* A bit too big to go on stack */ static char *next_avail = kdb_buffer; static int size_avail; static int suspend_grep; /* * search arg1 to see if it contains arg2 * (kdmain.c provides flags for ^pat and pat$) * * return 1 for found, 0 for not found */ static int kdb_search_string(char *searched, char *searchfor) { char firstchar, *cp; int len1, len2; /* not counting the newline at the end of "searched" */ len1 = strlen(searched)-1; len2 = strlen(searchfor); if (len1 < len2) return 0; if (kdb_grep_leading && kdb_grep_trailing && len1 != len2) return 0; if (kdb_grep_leading) { if (!strncmp(searched, searchfor, len2)) return 1; } else if (kdb_grep_trailing) { if (!strncmp(searched+len1-len2, searchfor, len2)) return 1; } else { firstchar = *searchfor; cp = searched; while ((cp = strchr(cp, firstchar))) { if (!strncmp(cp, searchfor, len2)) return 1; cp++; } } return 0; } int vkdb_printf(enum kdb_msgsrc src, const char *fmt, va_list ap) { int diag; int linecount; int colcount; int logging, saved_loglevel = 0; int saved_trap_printk; int got_printf_lock = 0; int retlen = 0; int fnd, len; char *cp, *cp2, *cphold = NULL, replaced_byte = ' '; char *moreprompt = "more> "; struct console *c = console_drivers; static DEFINE_SPINLOCK(kdb_printf_lock); unsigned long uninitialized_var(flags); preempt_disable(); saved_trap_printk = kdb_trap_printk; kdb_trap_printk = 0; /* Serialize kdb_printf if multiple cpus try to write at once. * But if any cpu goes recursive in kdb, just print the output, * even if it is interleaved with any other text. */ if (!KDB_STATE(PRINTF_LOCK)) { KDB_STATE_SET(PRINTF_LOCK); spin_lock_irqsave(&kdb_printf_lock, flags); got_printf_lock = 1; atomic_inc(&kdb_event); } else { __acquire(kdb_printf_lock); } diag = kdbgetintenv("LINES", &linecount); if (diag || linecount <= 1) linecount = 24; diag = kdbgetintenv("COLUMNS", &colcount); if (diag || colcount <= 1) colcount = 80; diag = kdbgetintenv("LOGGING", &logging); if (diag) logging = 0; if (!kdb_grepping_flag || suspend_grep) { /* normally, every vsnprintf starts a new buffer */ next_avail = kdb_buffer; size_avail = sizeof(kdb_buffer); } vsnprintf(next_avail, size_avail, fmt, ap); /* * If kdb_parse() found that the command was cmd xxx | grep yyy * then kdb_grepping_flag is set, and kdb_grep_string contains yyy * * Accumulate the print data up to a newline before searching it. * (vsnprintf does null-terminate the string that it generates) */ /* skip the search if prints are temporarily unconditional */ if (!suspend_grep && kdb_grepping_flag) { cp = strchr(kdb_buffer, '\n'); if (!cp) { /* * Special cases that don't end with newlines * but should be written without one: * The "[nn]kdb> " prompt should * appear at the front of the buffer. * * The "[nn]more " prompt should also be * (MOREPROMPT -> moreprompt) * written * but we print that ourselves, * we set the suspend_grep flag to make * it unconditional. * */ if (next_avail == kdb_buffer) { /* * these should occur after a newline, * so they will be at the front of the * buffer */ cp2 = kdb_buffer; len = strlen(kdb_prompt_str); if (!strncmp(cp2, kdb_prompt_str, len)) { /* * We're about to start a new * command, so we can go back * to normal mode. */ kdb_grepping_flag = 0; goto kdb_printit; } } /* no newline; don't search/write the buffer until one is there */ len = strlen(kdb_buffer); next_avail = kdb_buffer + len; size_avail = sizeof(kdb_buffer) - len; goto kdb_print_out; } /* * The newline is present; print through it or discard * it, depending on the results of the search. */ cp++; /* to byte after the newline */ replaced_byte = *cp; /* remember what/where it was */ cphold = cp; *cp = '\0'; /* end the string for our search */ /* * We now have a newline at the end of the string * Only continue with this output if it contains the * search string. */ fnd = kdb_search_string(kdb_buffer, kdb_grep_string); if (!fnd) { /* * At this point the complete line at the start * of kdb_buffer can be discarded, as it does * not contain what the user is looking for. * Shift the buffer left. */ *cphold = replaced_byte; strcpy(kdb_buffer, cphold); len = strlen(kdb_buffer); next_avail = kdb_buffer + len; size_avail = sizeof(kdb_buffer) - len; goto kdb_print_out; } /* * at this point the string is a full line and * should be printed, up to the null. */ } kdb_printit: /* * Write to all consoles. */ retlen = strlen(kdb_buffer); cp = (char *) printk_skip_level(kdb_buffer); if (!dbg_kdb_mode && kgdb_connected) { gdbstub_msg_write(cp, retlen - (cp - kdb_buffer)); } else { if (dbg_io_ops && !dbg_io_ops->is_console) { len = retlen - (cp - kdb_buffer); cp2 = cp; while (len--) { dbg_io_ops->write_char(*cp2); cp2++; } } while (c) { c->write(c, cp, retlen - (cp - kdb_buffer)); touch_nmi_watchdog(); c = c->next; } } if (logging) { saved_loglevel = console_loglevel; console_loglevel = CONSOLE_LOGLEVEL_SILENT; if (printk_get_level(kdb_buffer) || src == KDB_MSGSRC_PRINTK) printk("%s", kdb_buffer); else pr_info("%s", kdb_buffer); } if (KDB_STATE(PAGER)) { /* * Check printed string to decide how to bump the * kdb_nextline to control when the more prompt should * show up. */ int got = 0; len = retlen; while (len--) { if (kdb_buffer[len] == '\n') { kdb_nextline++; got = 0; } else if (kdb_buffer[len] == '\r') { got = 0; } else { got++; } } kdb_nextline += got / (colcount + 1); } /* check for having reached the LINES number of printed lines */ if (kdb_nextline >= linecount) { char buf1[16] = ""; /* Watch out for recursion here. Any routine that calls * kdb_printf will come back through here. And kdb_read * uses kdb_printf to echo on serial consoles ... */ kdb_nextline = 1; /* In case of recursion */ /* * Pause until cr. */ moreprompt = kdbgetenv("MOREPROMPT"); if (moreprompt == NULL) moreprompt = "more> "; kdb_input_flush(); c = console_drivers; if (dbg_io_ops && !dbg_io_ops->is_console) { len = strlen(moreprompt); cp = moreprompt; while (len--) { dbg_io_ops->write_char(*cp); cp++; } } while (c) { c->write(c, moreprompt, strlen(moreprompt)); touch_nmi_watchdog(); c = c->next; } if (logging) printk("%s", moreprompt); kdb_read(buf1, 2); /* '2' indicates to return * immediately after getting one key. */ kdb_nextline = 1; /* Really set output line 1 */ /* empty and reset the buffer: */ kdb_buffer[0] = '\0'; next_avail = kdb_buffer; size_avail = sizeof(kdb_buffer); if ((buf1[0] == 'q') || (buf1[0] == 'Q')) { /* user hit q or Q */ KDB_FLAG_SET(CMD_INTERRUPT); /* command interrupted */ KDB_STATE_CLEAR(PAGER); /* end of command output; back to normal mode */ kdb_grepping_flag = 0; kdb_printf("\n"); } else if (buf1[0] == ' ') { kdb_printf("\r"); suspend_grep = 1; /* for this recursion */ } else if (buf1[0] == '\n') { kdb_nextline = linecount - 1; kdb_printf("\r"); suspend_grep = 1; /* for this recursion */ } else if (buf1[0] && buf1[0] != '\n') { /* user hit something other than enter */ suspend_grep = 1; /* for this recursion */ kdb_printf("\nOnly 'q' or 'Q' are processed at more " "prompt, input ignored\n"); } else if (kdb_grepping_flag) { /* user hit enter */ suspend_grep = 1; /* for this recursion */ kdb_printf("\n"); } kdb_input_flush(); } /* * For grep searches, shift the printed string left. * replaced_byte contains the character that was overwritten with * the terminating null, and cphold points to the null. * Then adjust the notion of available space in the buffer. */ if (kdb_grepping_flag && !suspend_grep) { *cphold = replaced_byte; strcpy(kdb_buffer, cphold); len = strlen(kdb_buffer); next_avail = kdb_buffer + len; size_avail = sizeof(kdb_buffer) - len; } kdb_print_out: suspend_grep = 0; /* end of what may have been a recursive call */ if (logging) console_loglevel = saved_loglevel; if (KDB_STATE(PRINTF_LOCK) && got_printf_lock) { got_printf_lock = 0; spin_unlock_irqrestore(&kdb_printf_lock, flags); KDB_STATE_CLEAR(PRINTF_LOCK); atomic_dec(&kdb_event); } else { __release(kdb_printf_lock); } kdb_trap_printk = saved_trap_printk; preempt_enable(); return retlen; } int kdb_printf(const char *fmt, ...) { va_list ap; int r; va_start(ap, fmt); r = vkdb_printf(KDB_MSGSRC_INTERNAL, fmt, ap); va_end(ap); return r; } EXPORT_SYMBOL_GPL(kdb_printf);