vi: move key reading routine out of vi into llbbb

function                                             old     new   delta
read_key                                               -     310    +310
....
static.esccmds                                       170      61    -109
readit                                               286      60    -226
------------------------------------------------------------------------------
(add/remove: 1/0 grow/shrink: 9/10 up/down: 349/-367)         Total: -18 bytes

3 files changed, 78 insertions, 185 deletions

diff --git a/editors/vi.c b/editors/vi.c
index 55154dcd7..0e7b729fe 100644
--- a/editors/vi.c
+++ b/editors/vi.c
@@ -57,34 +57,6 @@ enum {
         MAX_SCR_ROWS = CONFIG_FEATURE_VI_MAX_LEN,
 };
 
-// "Keycodes" that report an escape sequence.
-// We use something which fits into signed char,
-// yet doesn't represent any valid Unicode characher.
-enum {
-        VI_K_UP       = -1,     // cursor key Up
-        VI_K_DOWN     = -2,     // cursor key Down
-        VI_K_RIGHT    = -3,     // Cursor Key Right
-        VI_K_LEFT     = -4,     // cursor key Left
-        VI_K_HOME     = -5,     // Cursor Key Home
-        VI_K_END      = -6,     // Cursor Key End
-        VI_K_INSERT   = -7,     // Cursor Key Insert
-        VI_K_DELETE   = -8,     // Cursor Key Insert
-        VI_K_PAGEUP   = -9,     // Cursor Key Page Up
-        VI_K_PAGEDOWN = -10,    // Cursor Key Page Down
-        VI_K_FUN1     = -11,    // Function Key F1
-        VI_K_FUN2     = -12,    // Function Key F2
-        VI_K_FUN3     = -13,    // Function Key F3
-        VI_K_FUN4     = -14,    // Function Key F4
-        VI_K_FUN5     = -15,    // Function Key F5
-        VI_K_FUN6     = -16,    // Function Key F6
-        VI_K_FUN7     = -17,    // Function Key F7
-        VI_K_FUN8     = -18,    // Function Key F8
-        VI_K_FUN9     = -19,    // Function Key F9
-        VI_K_FUN10    = -20,    // Function Key F10
-        VI_K_FUN11    = -21,    // Function Key F11
-        VI_K_FUN12    = -22,    // Function Key F12
-};
-
 /* vt102 typical ESC sequence */
 /* terminal standout start/normal ESC sequence */
 static const char SOs[] ALIGN1 = "\033[7m";
@@ -179,6 +151,7 @@ struct globals {
         char erase_char;         // the users erase character
         char last_input_char;    // last char read from user
 
+        smalluint chars_to_parse;
 #if ENABLE_FEATURE_VI_DOT_CMD
         smallint adding2q;       // are we currently adding user input to q
         int lmc_len;             // length of last_modifying_cmd
@@ -193,7 +166,7 @@ struct globals {
 #if ENABLE_FEATURE_VI_SEARCH
         char *last_search_pattern; // last pattern from a '/' or '?' search
 #endif
-        int chars_to_parse;
+
         /* former statics */
 #if ENABLE_FEATURE_VI_YANKMARK
         char *edit_file__cur_line;
@@ -259,9 +232,10 @@ struct globals {
 #define screensize              (G.screensize         )
 #define screenbegin             (G.screenbegin        )
 #define tabstop                 (G.tabstop            )
+#define last_forward_char       (G.last_forward_char  )
 #define erase_char              (G.erase_char         )
 #define last_input_char         (G.last_input_char    )
-#define last_forward_char       (G.last_forward_char  )
+#define chars_to_parse          (G.chars_to_parse     )
 #if ENABLE_FEATURE_VI_READONLY
 #define readonly_mode           (G.readonly_mode      )
 #else
@@ -274,7 +248,6 @@ struct globals {
 #define last_row                (G.last_row           )
 #define my_pid                  (G.my_pid             )
 #define last_search_pattern     (G.last_search_pattern)
-#define chars_to_parse          (G.chars_to_parse     )
 
 #define edit_file__cur_line     (G.edit_file__cur_line)
 #define refresh__old_offset     (G.refresh__old_offset)
@@ -2200,130 +2173,14 @@ static int mysleep(int hund)	// sleep for 'h' 1/100 seconds
 static int readit(void) // read (maybe cursor) key from stdin
 {
         int c;
-        int n;
-
-        // Known escape sequences for cursor and function keys.
-        static const struct esc_cmds {
-                const char seq[4];
-                signed char val;
-        } esccmds[] = {
-                {"OA"  , VI_K_UP      },   // Cursor Key Up
-                {"OB"  , VI_K_DOWN    },   // Cursor Key Down
-                {"OC"  , VI_K_RIGHT   },   // Cursor Key Right
-                {"OD"  , VI_K_LEFT    },   // Cursor Key Left
-                {"OH"  , VI_K_HOME    },   // Cursor Key Home
-                {"OF"  , VI_K_END     },   // Cursor Key End
-                {"OP"  , VI_K_FUN1    },   // Function Key F1
-                {"OQ"  , VI_K_FUN2    },   // Function Key F2
-                {"OR"  , VI_K_FUN3    },   // Function Key F3
-                {"OS"  , VI_K_FUN4    },   // Function Key F4
-
-                {"[A"  , VI_K_UP      },   // Cursor Key Up
-                {"[B"  , VI_K_DOWN    },   // Cursor Key Down
-                {"[C"  , VI_K_RIGHT   },   // Cursor Key Right
-                {"[D"  , VI_K_LEFT    },   // Cursor Key Left
-                {"[H"  , VI_K_HOME    },   // Cursor Key Home
-                {"[F"  , VI_K_END     },   // Cursor Key End
-                {"[1~" , VI_K_HOME    },   // Cursor Key Home
-                {"[2~" , VI_K_INSERT  },   // Cursor Key Insert
-                {"[3~" , VI_K_DELETE  },   // Cursor Key Delete
-                {"[4~" , VI_K_END     },   // Cursor Key End
-                {"[5~" , VI_K_PAGEUP  },   // Cursor Key Page Up
-                {"[6~" , VI_K_PAGEDOWN},   // Cursor Key Page Down
-                // careful: these have no terminating NUL!
-                {"[11~", VI_K_FUN1    },   // Function Key F1
-                {"[12~", VI_K_FUN2    },   // Function Key F2
-                {"[13~", VI_K_FUN3    },   // Function Key F3
-                {"[14~", VI_K_FUN4    },   // Function Key F4
-                {"[15~", VI_K_FUN5    },   // Function Key F5
-                {"[17~", VI_K_FUN6    },   // Function Key F6
-                {"[18~", VI_K_FUN7    },   // Function Key F7
-                {"[19~", VI_K_FUN8    },   // Function Key F8
-                {"[20~", VI_K_FUN9    },   // Function Key F9
-                {"[21~", VI_K_FUN10   },   // Function Key F10
-                {"[23~", VI_K_FUN11   },   // Function Key F11
-                {"[24~", VI_K_FUN12   },   // Function Key F12
-        };
 
         fflush(stdout);
-
-        n = chars_to_parse;
-        if (n == 0) {
-                // If no data, block waiting for input.  (If we read more than the
-                // minimal ESC sequence size, the "n=0" below would instead have to
-                // figure out how much to keep, resulting in larger code.)
-                n = safe_read(0, readbuffer, 3);
-                if (n <= 0) {
- error:
-                        go_bottom_and_clear_to_eol();
-                        cookmode(); // terminal to "cooked"
-                        bb_error_msg_and_die("can't read user input");
-                }
-        }
-
-        // Grab character to return from buffer
-        c = (unsigned char)readbuffer[0];
-        // Returning NUL from this routine would be bad.
-        if (c == '\0')
-                c = ' ';
-        n--;
-        if (n) memmove(readbuffer, readbuffer + 1, n);
-
-        // If it's an escape sequence, loop through known matches.
-        if (c == 27) {
-                const struct esc_cmds *eindex;
-                struct pollfd pfd;
-
-                pfd.fd = STDIN_FILENO;
-                pfd.events = POLLIN;
-                for (eindex = esccmds; eindex < esccmds + ARRAY_SIZE(esccmds); eindex++)
-                {
-                        // n - position in sequence we did not read yet
-                        int i = 0; // position in sequence to compare
-
-                        // Loop through chars in this sequence
-                        for (;;) {
-                                // So far escape sequence matches up to [i-1]
-                                if (n <= i) {
-                                        // Need more chars, read another one if it wouldn't block.
-                                        // (Note that escape sequences come in as a unit,
-                                        // so if we would block it's not really an escape sequence.)
-
-                                        // Timeout is needed to reconnect escape sequences
-                                        // split up by transmission over a serial console.
-
-                                        if (safe_poll(&pfd, 1, 50)) {
-                                                if (safe_read(0, readbuffer + n, 1) <= 0)
-                                                        goto error;
-                                                n++;
-                                        } else {
-                                                // No more data!
-                                                // Array is sorted from shortest to longest,
-                                                // we can't match anything later in array,
-                                                // break out of both loops.
-                                                goto loop_out;
-                                        }
-                                }
-                                if (readbuffer[i] != eindex->seq[i])
-                                        break; // try next seq
-                                i++;
-                                if (i == 4 || !eindex->seq[i]) { // entire seq matched
-                                        c = eindex->val; // sign extended!
-                                        n = 0;
-                                        // n -= i; memmove(...);
-                                        // would be more correct,
-                                        // but we never read ahead that much,
-                                        // and n == i here.
-                                        goto loop_out;
-                                }
-                        }
-                }
-                // We did not find matching sequence, it was a bare ESC.
-                // We possibly read and stored more input in readbuffer by now.
+        c = read_key(STDIN_FILENO, &chars_to_parse, readbuffer);
+        if (c == -1) { // EOF/error
+                go_bottom_and_clear_to_eol();
+                cookmode(); // terminal to "cooked"
+                bb_error_msg_and_die("can't read user input");
         }
- loop_out:
-
-        chars_to_parse = n;
         return c;
 }
 
@@ -3013,21 +2870,21 @@ static void do_cmd(int c)
 
         /* if this is a cursor key, skip these checks */
         switch (c) {
-                case VI_K_UP:
-                case VI_K_DOWN:
-                case VI_K_LEFT:
-                case VI_K_RIGHT:
-                case VI_K_HOME:
-                case VI_K_END:
-                case VI_K_PAGEUP:
-                case VI_K_PAGEDOWN:
-                case VI_K_DELETE:
+                case KEYCODE_UP:
+                case KEYCODE_DOWN:
+                case KEYCODE_LEFT:
+                case KEYCODE_RIGHT:
+                case KEYCODE_HOME:
+                case KEYCODE_END:
+                case KEYCODE_PAGEUP:
+                case KEYCODE_PAGEDOWN:
+                case KEYCODE_DELETE:
                         goto key_cmd_mode;
         }
 
         if (cmd_mode == 2) {
                 //  flip-flop Insert/Replace mode
-                if (c == VI_K_INSERT)
+                if (c == KEYCODE_INSERT)
                         goto dc_i;
                 // we are 'R'eplacing the current *dot with new char
                 if (*dot == '\n') {
@@ -3044,7 +2901,7 @@ static void do_cmd(int c)
         }
         if (cmd_mode == 1) {
                 //  hitting "Insert" twice means "R" replace mode
-                if (c == VI_K_INSERT) goto dc5;
+                if (c == KEYCODE_INSERT) goto dc5;
                 // insert the char c at "dot"
                 if (1 <= c || Isprint(c)) {
                         dot = char_insert(dot, c);
@@ -3108,7 +2965,7 @@ static void do_cmd(int c)
         case 0x00:                      // nul- ignore
                 break;
         case 2:                 // ctrl-B  scroll up   full screen
-        case VI_K_PAGEUP:       // Cursor Key Page Up
+        case KEYCODE_PAGEUP:    // Cursor Key Page Up
                 dot_scroll(rows - 2, -1);
                 break;
         case 4:                 // ctrl-D  scroll down half screen
@@ -3118,14 +2975,14 @@ static void do_cmd(int c)
                 dot_scroll(1, 1);
                 break;
         case 6:                 // ctrl-F  scroll down full screen
-        case VI_K_PAGEDOWN:     // Cursor Key Page Down
+        case KEYCODE_PAGEDOWN:  // Cursor Key Page Down
                 dot_scroll(rows - 2, 1);
                 break;
         case 7:                 // ctrl-G  show current status
                 last_status_cksum = 0;  // force status update
                 break;
         case 'h':                       // h- move left
-        case VI_K_LEFT: // cursor key Left
+        case KEYCODE_LEFT:      // cursor key Left
         case 8:         // ctrl-H- move left    (This may be ERASE char)
         case 0x7f:      // DEL- move left   (This may be ERASE char)
                 if (cmdcnt-- > 1) {
@@ -3135,7 +2992,7 @@ static void do_cmd(int c)
                 break;
         case 10:                        // Newline ^J
         case 'j':                       // j- goto next line, same col
-        case VI_K_DOWN: // cursor key Down
+        case KEYCODE_DOWN:      // cursor key Down
                 if (cmdcnt-- > 1) {
                         do_cmd(c);
                 }                               // repeat cnt
@@ -3174,7 +3031,7 @@ static void do_cmd(int c)
                 break;
         case ' ':                       // move right
         case 'l':                       // move right
-        case VI_K_RIGHT:        // Cursor Key Right
+        case KEYCODE_RIGHT:     // Cursor Key Right
                 if (cmdcnt-- > 1) {
                         do_cmd(c);
                 }                               // repeat cnt
@@ -3259,7 +3116,7 @@ static void do_cmd(int c)
                 break;
 #endif /* FEATURE_VI_YANKMARK */
         case '$':                       // $- goto end of line
-        case VI_K_END:          // Cursor Key End
+        case KEYCODE_END:               // Cursor Key End
                 if (cmdcnt-- > 1) {
                         do_cmd(c);
                 }                               // repeat cnt
@@ -3584,7 +3441,7 @@ static void do_cmd(int c)
                 dot_skip_over_ws();
                 //**** fall through to ... 'i'
         case 'i':                       // i- insert before current char
-        case VI_K_INSERT:       // Cursor Key Insert
+        case KEYCODE_INSERT:    // Cursor Key Insert
  dc_i:
                 cmd_mode = 1;   // start insrting
                 break;
@@ -3637,7 +3494,7 @@ static void do_cmd(int c)
  dc5:
                 cmd_mode = 2;
                 break;
-        case VI_K_DELETE:
+        case KEYCODE_DELETE:
                 c = 'x';
                 // fall through
         case 'X':                       // X- delete char before dot
@@ -3787,7 +3644,7 @@ static void do_cmd(int c)
                 break;
         }
         case 'k':                       // k- goto prev line, same col
-        case VI_K_UP:           // cursor key Up
+        case KEYCODE_UP:                // cursor key Up
                 if (cmdcnt-- > 1) {
                         do_cmd(c);
                 }                               // repeat cnt
@@ -3852,23 +3709,25 @@ static void do_cmd(int c)
                 end_cmd_q();    // stop adding to q
                 break;
                 //----- The Cursor and Function Keys -----------------------------
-        case VI_K_HOME: // Cursor Key Home
+        case KEYCODE_HOME:      // Cursor Key Home
                 dot_begin();
                 break;
                 // The Fn keys could point to do_macro which could translate them
-        case VI_K_FUN1: // Function Key F1
-        case VI_K_FUN2: // Function Key F2
-        case VI_K_FUN3: // Function Key F3
-        case VI_K_FUN4: // Function Key F4
-        case VI_K_FUN5: // Function Key F5
-        case VI_K_FUN6: // Function Key F6
-        case VI_K_FUN7: // Function Key F7
-        case VI_K_FUN8: // Function Key F8
-        case VI_K_FUN9: // Function Key F9
-        case VI_K_FUN10:        // Function Key F10
-        case VI_K_FUN11:        // Function Key F11
-        case VI_K_FUN12:        // Function Key F12
+#if 0
+        case KEYCODE_FUN1:      // Function Key F1
+        case KEYCODE_FUN2:      // Function Key F2
+        case KEYCODE_FUN3:      // Function Key F3
+        case KEYCODE_FUN4:      // Function Key F4
+        case KEYCODE_FUN5:      // Function Key F5
+        case KEYCODE_FUN6:      // Function Key F6
+        case KEYCODE_FUN7:      // Function Key F7
+        case KEYCODE_FUN8:      // Function Key F8
+        case KEYCODE_FUN9:      // Function Key F9
+        case KEYCODE_FUN10:     // Function Key F10
+        case KEYCODE_FUN11:     // Function Key F11
+        case KEYCODE_FUN12:     // Function Key F12
                 break;
+#endif
         }
 
  dc1:
diff --git a/include/libbb.h b/include/libbb.h
index 5b92574dd..931710962 100644
--- a/include/libbb.h
+++ b/include/libbb.h
@@ -921,6 +921,39 @@ void bb_displayroutes(int noresolve, int netstatfmt) FAST_FUNC;
 #endif
 
 
+/* "Keycodes" that report an escape sequence.
+ * We use something which fits into signed char,
+ * yet doesn't represent any valid Unicode characher.
+ * Also, -1 is reserved for error indication and we don't use it. */
+enum {
+        KEYCODE_UP       =  -2, 
+        KEYCODE_DOWN     =  -3,
+        KEYCODE_RIGHT    =  -4,
+        KEYCODE_LEFT     =  -5,
+        KEYCODE_HOME     =  -6,
+        KEYCODE_END      =  -7,
+        KEYCODE_INSERT   =  -8,
+        KEYCODE_DELETE   =  -9,
+        KEYCODE_PAGEUP   = -10,
+        KEYCODE_PAGEDOWN = -11,
+#if 0
+        KEYCODE_FUN1     = -12,
+        KEYCODE_FUN2     = -13,
+        KEYCODE_FUN3     = -14,
+        KEYCODE_FUN4     = -15,
+        KEYCODE_FUN5     = -16,
+        KEYCODE_FUN6     = -17,
+        KEYCODE_FUN7     = -18,
+        KEYCODE_FUN8     = -19,
+        KEYCODE_FUN9     = -20,
+        KEYCODE_FUN10    = -21,
+        KEYCODE_FUN11    = -22,
+        KEYCODE_FUN12    = -23,
+#endif
+};
+int read_key(int fd, smalluint *nbuffered, char *buffer) FAST_FUNC;
+
+
 /* Networking */
 int create_icmp_socket(void) FAST_FUNC;
 int create_icmp6_socket(void) FAST_FUNC;
diff --git a/libbb/Kbuild b/libbb/Kbuild
index 726200675..786cbee80 100644
--- a/libbb/Kbuild
+++ b/libbb/Kbuild
@@ -75,6 +75,7 @@ lib-y += process_escape_sequence.o
 lib-y += procps.o
 lib-y += ptr_to_globals.o
 lib-y += read.o
+lib-y += read_key.o
 lib-y += recursive_action.o
 lib-y += remove_file.o
 lib-y += restricted_shell.o