diff options
Diffstat (limited to 'kernel/debug')
| -rw-r--r-- | kernel/debug/kdb/kdb_bt.c | 22 | ||||
| -rw-r--r-- | kernel/debug/kdb/kdb_io.c | 61 | ||||
| -rw-r--r-- | kernel/debug/kdb/kdb_private.h | 1 |
3 files changed, 42 insertions, 42 deletions
diff --git a/kernel/debug/kdb/kdb_bt.c b/kernel/debug/kdb/kdb_bt.c index 0e94efe07b72..4af48ac53625 100644 --- a/kernel/debug/kdb/kdb_bt.c +++ b/kernel/debug/kdb/kdb_bt.c @@ -75,9 +75,10 @@ static void kdb_show_stack(struct task_struct *p, void *addr) static int kdb_bt1(struct task_struct *p, unsigned long mask, bool btaprompt) { - char buffer[2]; - if (kdb_getarea(buffer[0], (unsigned long)p) || - kdb_getarea(buffer[0], (unsigned long)(p+1)-1)) + char ch; + + if (kdb_getarea(ch, (unsigned long)p) || + kdb_getarea(ch, (unsigned long)(p+1)-1)) return KDB_BADADDR; if (!kdb_task_state(p, mask)) return 0; @@ -85,12 +86,17 @@ kdb_bt1(struct task_struct *p, unsigned long mask, bool btaprompt) kdb_ps1(p); kdb_show_stack(p, NULL); if (btaprompt) { - kdb_getstr(buffer, sizeof(buffer), - "Enter <q> to end, <cr> to continue:"); - if (buffer[0] == 'q') { - kdb_printf("\n"); + kdb_printf("Enter <q> to end, <cr> or <space> to continue:"); + do { + ch = kdb_getchar(); + } while (!strchr("\r\n q", ch)); + kdb_printf("\n"); + + /* reset the pager */ + kdb_nextline = 1; + + if (ch == 'q') return 1; - } } touch_nmi_watchdog(); return 0; diff --git a/kernel/debug/kdb/kdb_io.c b/kernel/debug/kdb/kdb_io.c index a92ceca29637..9b6933d585b5 100644 --- a/kernel/debug/kdb/kdb_io.c +++ b/kernel/debug/kdb/kdb_io.c @@ -108,7 +108,22 @@ static int kdb_handle_escape(char *buf, size_t sz) return -1; } -static int kdb_read_get_key(char *buffer, size_t bufsize) +/** + * 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 */ @@ -126,7 +141,6 @@ static int kdb_read_get_key(char *buffer, size_t bufsize) } key = (*f)(); - if (key == -1) { if (escape_delay) { udelay(ESCAPE_UDELAY); @@ -136,14 +150,6 @@ static int kdb_read_get_key(char *buffer, size_t bufsize) 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; @@ -184,17 +190,7 @@ static int kdb_read_get_key(char *buffer, size_t bufsize) * 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. + * The buffer size must be >= 2. */ static char *kdb_read(char *buffer, size_t bufsize) @@ -229,9 +225,7 @@ static char *kdb_read(char *buffer, size_t bufsize) *cp = '\0'; kdb_printf("%s", buffer); poll_again: - key = kdb_read_get_key(buffer, bufsize); - if (key == -1) - return buffer; + key = kdb_getchar(); if (key != 9) tab = 0; switch (key) { @@ -742,7 +736,7 @@ kdb_printit: /* check for having reached the LINES number of printed lines */ if (kdb_nextline >= linecount) { - char buf1[16] = ""; + char ch; /* Watch out for recursion here. Any routine that calls * kdb_printf will come back through here. And kdb_read @@ -777,39 +771,38 @@ kdb_printit: if (logging) printk("%s", moreprompt); - kdb_read(buf1, 2); /* '2' indicates to return - * immediately after getting one key. */ + ch = kdb_getchar(); 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')) { + if ((ch == 'q') || (ch == '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] == ' ') { + } else if (ch == ' ') { kdb_printf("\r"); suspend_grep = 1; /* for this recursion */ - } else if (buf1[0] == '\n') { + } else if (ch == '\n' || ch == '\r') { kdb_nextline = linecount - 1; kdb_printf("\r"); suspend_grep = 1; /* for this recursion */ - } else if (buf1[0] == '/' && !kdb_grepping_flag) { + } else if (ch == '/' && !kdb_grepping_flag) { kdb_printf("\r"); kdb_getstr(kdb_grep_string, KDB_GREP_STRLEN, kdbgetenv("SEARCHPROMPT") ?: "search> "); *strchrnul(kdb_grep_string, '\n') = '\0'; kdb_grepping_flag += KDB_GREPPING_FLAG_SEARCH; suspend_grep = 1; /* for this recursion */ - } else if (buf1[0] && buf1[0] != '\n') { - /* user hit something other than enter */ + } else if (ch) { + /* user hit something unexpected */ suspend_grep = 1; /* for this recursion */ - if (buf1[0] != '/') + if (ch != '/') kdb_printf( "\nOnly 'q', 'Q' or '/' are processed at " "more prompt, input ignored\n"); diff --git a/kernel/debug/kdb/kdb_private.h b/kernel/debug/kdb/kdb_private.h index 2118d8258b7c..55d052061ef9 100644 --- a/kernel/debug/kdb/kdb_private.h +++ b/kernel/debug/kdb/kdb_private.h @@ -210,6 +210,7 @@ extern void kdb_ps1(const struct task_struct *p); extern void kdb_print_nameval(const char *name, unsigned long val); extern void kdb_send_sig(struct task_struct *p, int sig); extern void kdb_meminfo_proc_show(void); +extern char kdb_getchar(void); extern char *kdb_getstr(char *, size_t, const char *); extern void kdb_gdb_state_pass(char *buf); |