diff options
| -rw-r--r-- | kernel/debug/kdb/kdb_io.c | 128 |
1 files changed, 67 insertions, 61 deletions
diff --git a/kernel/debug/kdb/kdb_io.c b/kernel/debug/kdb/kdb_io.c index 3a5184eb6977..cfc054fd8097 100644 --- a/kernel/debug/kdb/kdb_io.c +++ b/kernel/debug/kdb/kdb_io.c @@ -49,6 +49,65 @@ static int kgdb_transition_check(char *buffer) 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; +} + static int kdb_read_get_key(char *buffer, size_t bufsize) { #define ESCAPE_UDELAY 1000 @@ -102,68 +161,15 @@ static int kdb_read_get_key(char *buffer, size_t bufsize) escape_delay = 2; continue; } - if (ped - escape_data == 1) { - /* \e */ - continue; - } else if (ped - escape_data == 2) { - /* \e<something> */ - if (key != '[') - escape_delay = 2; - continue; - } else if (ped - escape_data == 3) { - /* \e[<something> */ - 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><something> */ - 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; + + key = kdb_handle_escape(escape_data, ped - escape_data); + if (key > 0) { + escape_data[0] = key; + escape_data[1] = '\0'; } + if (key) + escape_delay = 2; + continue; } break; /* A key to process */ } |