2 * Copyright (C) 1984-2015 Mark Nudelman
4 * You may distribute under the terms of either the GNU General Public
5 * License or the Less License, as specified in the README file.
7 * For more information, see the README file.
12 * Routines to decode user commands.
14 * This is all table driven.
15 * A command table is a sequence of command descriptors.
16 * Each command descriptor is a sequence of bytes with the following format:
17 * <c1><c2>...<cN><0><action>
18 * The characters c1,c2,...,cN are the command string; that is,
19 * the characters which the user must type.
20 * It is terminated by a null <0> byte.
21 * The byte after the null byte is the action code associated
22 * with the command string.
23 * If an action byte is OR-ed with A_EXTRA, this indicates
24 * that the option byte is followed by an extra string.
26 * There may be many command tables.
27 * The first (default) table is built-in.
28 * Other tables are read in from "lesskey" files.
29 * All the tables are linked together and are searched in order.
36 extern int erase_char
, erase2_char
, kill_char
;
40 SK_SPECIAL_KEY, (k), 6, 1, 1, 1
42 * Command table is ordered roughly according to expected
43 * frequency of use, so the common commands are near the beginning.
46 static unsigned char cmdtable
[] =
52 SK(SK_DOWN_ARROW
),0, A_F_LINE
,
53 CONTROL('E'),0, A_F_LINE
,
54 CONTROL('N'),0, A_F_LINE
,
57 CONTROL('Y'),0, A_B_LINE
,
58 SK(SK_CONTROL_K
),0, A_B_LINE
,
59 CONTROL('P'),0, A_B_LINE
,
60 SK(SK_UP_ARROW
),0, A_B_LINE
,
65 CONTROL('D'),0, A_F_SCROLL
,
67 CONTROL('U'),0, A_B_SCROLL
,
70 CONTROL('F'),0, A_F_SCREEN
,
71 CONTROL('V'),0, A_F_SCREEN
,
72 SK(SK_PAGE_DOWN
),0, A_F_SCREEN
,
74 CONTROL('B'),0, A_B_SCREEN
,
75 ESC
,'v',0, A_B_SCREEN
,
76 SK(SK_PAGE_UP
),0, A_B_SCREEN
,
79 ESC
,' ',0, A_FF_SCREEN
,
81 ESC
,'F',0, A_F_UNTIL_HILITE
,
84 CONTROL('R'),0, A_REPAINT
,
85 CONTROL('L'),0, A_REPAINT
,
86 ESC
,'u',0, A_UNDO_SEARCH
,
88 SK(SK_HOME
),0, A_GOLINE
,
97 SK(SK_RIGHT_ARROW
),0, A_RSHIFT
,
98 SK(SK_LEFT_ARROW
),0, A_LSHIFT
,
99 '{',0, A_F_BRACKET
|A_EXTRA
, '{','}',0,
100 '}',0, A_B_BRACKET
|A_EXTRA
, '{','}',0,
101 '(',0, A_F_BRACKET
|A_EXTRA
, '(',')',0,
102 ')',0, A_B_BRACKET
|A_EXTRA
, '(',')',0,
103 '[',0, A_F_BRACKET
|A_EXTRA
, '[',']',0,
104 ']',0, A_B_BRACKET
|A_EXTRA
, '[',']',0,
105 ESC
,CONTROL('F'),0, A_F_BRACKET
,
106 ESC
,CONTROL('B'),0, A_B_BRACKET
,
108 ESC
,'G',0, A_GOEND_BUF
,
111 SK(SK_END
),0, A_GOEND
,
127 CONTROL('G'),0, A_STAT
,
131 ESC
,'/',0, A_F_SEARCH
|A_EXTRA
, '*',0,
132 ESC
,'?',0, A_B_SEARCH
|A_EXTRA
, '*',0,
133 'n',0, A_AGAIN_SEARCH
,
134 ESC
,'n',0, A_T_AGAIN_SEARCH
,
135 'N',0, A_REVERSE_SEARCH
,
136 ESC
,'N',0, A_T_REVERSE_SEARCH
,
140 CONTROL('X'),CONTROL('X'),0, A_GOMARK
,
142 ':','e',0, A_EXAMINE
,
143 CONTROL('X'),CONTROL('V'),0, A_EXAMINE
,
144 ':','n',0, A_NEXT_FILE
,
145 ':','p',0, A_PREV_FILE
,
148 ':','x',0, A_INDEX_FILE
,
149 ':','d',0, A_REMOVE_FILE
,
151 ':','t',0, A_OPT_TOGGLE
|A_EXTRA
, 't',0,
152 's',0, A_OPT_TOGGLE
|A_EXTRA
, 'o',0,
153 '_',0, A_DISP_OPTION
,
170 static unsigned char edittable
[] =
172 '\t',0, EC_F_COMPLETE
, /* TAB */
173 '\17',0, EC_B_COMPLETE
, /* BACKTAB */
174 SK(SK_BACKTAB
),0, EC_B_COMPLETE
, /* BACKTAB */
175 ESC
,'\t',0, EC_B_COMPLETE
, /* ESC TAB */
176 CONTROL('L'),0, EC_EXPAND
, /* CTRL-L */
177 CONTROL('V'),0, EC_LITERAL
, /* BACKSLASH */
178 CONTROL('A'),0, EC_LITERAL
, /* BACKSLASH */
179 ESC
,'l',0, EC_RIGHT
, /* ESC l */
180 SK(SK_RIGHT_ARROW
),0, EC_RIGHT
, /* RIGHTARROW */
181 ESC
,'h',0, EC_LEFT
, /* ESC h */
182 SK(SK_LEFT_ARROW
),0, EC_LEFT
, /* LEFTARROW */
183 ESC
,'b',0, EC_W_LEFT
, /* ESC b */
184 ESC
,SK(SK_LEFT_ARROW
),0, EC_W_LEFT
, /* ESC LEFTARROW */
185 SK(SK_CTL_LEFT_ARROW
),0, EC_W_LEFT
, /* CTRL-LEFTARROW */
186 ESC
,'w',0, EC_W_RIGHT
, /* ESC w */
187 ESC
,SK(SK_RIGHT_ARROW
),0, EC_W_RIGHT
, /* ESC RIGHTARROW */
188 SK(SK_CTL_RIGHT_ARROW
),0, EC_W_RIGHT
, /* CTRL-RIGHTARROW */
189 ESC
,'i',0, EC_INSERT
, /* ESC i */
190 SK(SK_INSERT
),0, EC_INSERT
, /* INSERT */
191 ESC
,'x',0, EC_DELETE
, /* ESC x */
192 SK(SK_DELETE
),0, EC_DELETE
, /* DELETE */
193 ESC
,'X',0, EC_W_DELETE
, /* ESC X */
194 ESC
,SK(SK_DELETE
),0, EC_W_DELETE
, /* ESC DELETE */
195 SK(SK_CTL_DELETE
),0, EC_W_DELETE
, /* CTRL-DELETE */
196 SK(SK_CTL_BACKSPACE
),0, EC_W_BACKSPACE
, /* CTRL-BACKSPACE */
197 ESC
,'\b',0, EC_W_BACKSPACE
, /* ESC BACKSPACE */
198 ESC
,'0',0, EC_HOME
, /* ESC 0 */
199 SK(SK_HOME
),0, EC_HOME
, /* HOME */
200 ESC
,'$',0, EC_END
, /* ESC $ */
201 SK(SK_END
),0, EC_END
, /* END */
202 ESC
,'k',0, EC_UP
, /* ESC k */
203 SK(SK_UP_ARROW
),0, EC_UP
, /* UPARROW */
204 ESC
,'j',0, EC_DOWN
, /* ESC j */
205 SK(SK_DOWN_ARROW
),0, EC_DOWN
, /* DOWNARROW */
206 CONTROL('G'),0, EC_ABORT
, /* CTRL-G */
210 * Structure to support a list of command tables.
214 struct tablelist
*t_next
;
220 * List of command tables and list of line-edit tables.
222 static struct tablelist
*list_fcmd_tables
= NULL
;
223 static struct tablelist
*list_ecmd_tables
= NULL
;
224 static struct tablelist
*list_var_tables
= NULL
;
225 static struct tablelist
*list_sysvar_tables
= NULL
;
229 * Expand special key abbreviations in a command table.
232 expand_special_keys(table
, len
)
242 for (fm
= table
; fm
< table
+ len
; )
245 * Rewrite each command in the table with any
246 * special key abbreviations expanded.
248 for (to
= fm
; *fm
!= '\0'; )
250 if (*fm
!= SK_SPECIAL_KEY
)
256 * After SK_SPECIAL_KEY, next byte is the type
257 * of special key (one of the SK_* contants),
258 * and the byte after that is the number of bytes,
259 * N, reserved by the abbreviation (including the
260 * SK_SPECIAL_KEY and key type bytes).
261 * Replace all N bytes with the actual bytes
262 * output by the special key on this terminal.
264 repl
= special_key_str(fm
[1]);
267 if (repl
== NULL
|| (int) strlen(repl
) > klen
)
269 while (*repl
!= '\0')
274 * Fill any unused bytes between end of command and
275 * the action byte with A_SKIP.
283 while (*fm
++ != '\0')
290 * Initialize the command lists.
296 * Add the default command tables.
298 add_fcmd_table((char*)cmdtable
, sizeof(cmdtable
));
299 add_ecmd_table((char*)edittable
, sizeof(edittable
));
302 * For backwards compatibility,
303 * try to add tables in the OLD system lesskey file.
306 add_hometable(NULL
, BINDIR
"/.sysless", 1);
309 * Try to add the tables in the system lesskey file.
311 add_hometable("LESSKEY_SYSTEM", LESSKEYFILE_SYS
, 1);
313 * Try to add the tables in the standard lesskey file "$HOME/.less".
315 add_hometable("LESSKEY", LESSKEYFILE
, 0);
320 * Add a command table.
323 add_cmd_table(tlist
, buf
, len
)
324 struct tablelist
**tlist
;
328 register struct tablelist
*t
;
333 * Allocate a tablelist structure, initialize it,
334 * and link it into the list of tables.
336 if ((t
= (struct tablelist
*)
337 calloc(1, sizeof(struct tablelist
))) == NULL
)
341 expand_special_keys(buf
, len
);
343 t
->t_end
= buf
+ len
;
350 * Add a command table.
353 add_fcmd_table(buf
, len
)
357 if (add_cmd_table(&list_fcmd_tables
, buf
, len
) < 0)
358 error("Warning: some commands disabled", NULL_PARG
);
362 * Add an editing command table.
365 add_ecmd_table(buf
, len
)
369 if (add_cmd_table(&list_ecmd_tables
, buf
, len
) < 0)
370 error("Warning: some edit commands disabled", NULL_PARG
);
374 * Add an environment variable table.
377 add_var_table(tlist
, buf
, len
)
378 struct tablelist
**tlist
;
382 if (add_cmd_table(tlist
, buf
, len
) < 0)
383 error("Warning: environment variables from lesskey file unavailable", NULL_PARG
);
387 * Search a single command table for the command string in cmd.
390 cmd_search(cmd
, table
, endtable
, sp
)
401 for (p
= table
, q
= cmd
; p
< endtable
; p
++, q
++)
406 * Current characters match.
407 * If we're at the end of the string, we've found it.
408 * Return the action code, which is the character
409 * after the null at the end of the string
410 * in the command table.
420 * We get here only if the original
421 * cmd string passed in was empty ("").
422 * I don't think that can happen,
423 * but just in case ...
428 * Check for an "extra" string.
437 } else if (*q
== '\0')
440 * Hit the end of the user's command,
441 * but not the end of the string in the command table.
442 * The user's command is incomplete.
449 * Skip ahead to the next command in the
450 * command table, and reset the pointer
451 * to the beginning of the user's command.
453 if (*p
== '\0' && p
[1] == A_END_LIST
)
456 * A_END_LIST is a special marker that tells
457 * us to abort the cmd search.
472 * No match found in the entire command table.
478 * Decode a command character and return the associated action.
479 * The "extra" string, if any, is returned in sp.
482 cmd_decode(tlist
, cmd
, sp
)
483 struct tablelist
*tlist
;
487 register struct tablelist
*t
;
488 register int action
= A_INVALID
;
491 * Search thru all the command tables.
492 * Stop when we find an action which is not A_INVALID.
494 for (t
= tlist
; t
!= NULL
; t
= t
->t_next
)
496 action
= cmd_search(cmd
, t
->t_start
, t
->t_end
, sp
);
497 if (action
!= A_INVALID
)
500 if (action
== A_UINVALID
)
506 * Decode a command from the cmdtables list.
513 return (cmd_decode(list_fcmd_tables
, cmd
, sp
));
517 * Decode a command from the edittables list.
524 return (cmd_decode(list_ecmd_tables
, cmd
, sp
));
528 * Get the value of an environment variable.
529 * Looks first in the lesskey file, then in the real environment.
538 a
= cmd_decode(list_var_tables
, var
, &s
);
542 if (s
!= NULL
&& *s
!= '\0')
544 a
= cmd_decode(list_sysvar_tables
, var
, &s
);
552 * Get an "integer" from a lesskey file.
553 * Integers are stored in a funny format:
554 * two bytes, low order first, in radix KRADIX.
563 n
+= *(*sp
)++ * KRADIX
;
568 * Process an old (pre-v241) lesskey file.
571 old_lesskey(buf
, len
)
576 * Old-style lesskey file.
577 * The file must end with either
579 * or ...,cmd,0,action|A_EXTRA,string,0
580 * So the last byte or the second to last byte must be zero.
582 if (buf
[len
-1] != '\0' && buf
[len
-2] != '\0')
584 add_fcmd_table(buf
, len
);
589 * Process a new (post-v241) lesskey file.
592 new_lesskey(buf
, len
, sysvar
)
602 * New-style lesskey file.
603 * Extract the pieces.
605 if (buf
[len
-3] != C0_END_LESSKEY_MAGIC
||
606 buf
[len
-2] != C1_END_LESSKEY_MAGIC
||
607 buf
[len
-1] != C2_END_LESSKEY_MAGIC
)
617 add_fcmd_table(p
, n
);
622 add_ecmd_table(p
, n
);
627 add_var_table((sysvar
) ?
628 &list_sysvar_tables
: &list_var_tables
, p
, n
);
635 * Unrecognized section type.
643 * Set up a user command table, based on a "lesskey" file.
646 lesskey(filename
, sysvar
)
651 register POSITION len
;
658 * Try to open the lesskey file.
660 filename
= shell_unquote(filename
);
661 f
= open(filename
, OPEN_READ
);
667 * Read the file into a buffer.
668 * We first figure out the size of the file and allocate space for it.
669 * {{ Minimal error checking is done here.
670 * A garbage .less file will produce strange results.
671 * To avoid a large amount of error checking code here, we
672 * rely on the lesskey program to generate a good .less file. }}
675 if (len
== NULL_POSITION
|| len
< 3)
678 * Bad file (valid file must have at least 3 chars).
683 if ((buf
= (char *) calloc((int)len
, sizeof(char))) == NULL
)
688 if (lseek(f
, (off_t
)0, SEEK_SET
) == BAD_LSEEK
)
694 n
= read(f
, buf
, (unsigned int) len
);
703 * Figure out if this is an old-style (before version 241)
704 * or new-style lesskey file format.
706 if (buf
[0] != C0_LESSKEY_MAGIC
|| buf
[1] != C1_LESSKEY_MAGIC
||
707 buf
[2] != C2_LESSKEY_MAGIC
|| buf
[3] != C3_LESSKEY_MAGIC
)
708 return (old_lesskey(buf
, (int)len
));
709 return (new_lesskey(buf
, (int)len
, sysvar
));
713 * Add the standard lesskey file "$HOME/.less"
716 add_hometable(envname
, def_filename
, sysvar
)
724 if (envname
!= NULL
&& (filename
= lgetenv(envname
)) != NULL
)
725 filename
= save(filename
);
727 filename
= save(def_filename
);
729 filename
= homefile(def_filename
);
730 if (filename
== NULL
)
732 if (lesskey(filename
, sysvar
) < 0)
734 parg
.p_string
= filename
;
735 error("Cannot use lesskey file \"%s\"", &parg
);
742 * See if a char is a special line-editing command.
752 char usercmd
[MAX_CMDLEN
+1];
755 * An editing character could actually be a sequence of characters;
756 * for example, an escape sequence sent by pressing the uparrow key.
757 * To match the editing string, we use the command decoder
758 * but give it the edit-commands command table
759 * This table is constructed to match the user's keyboard.
761 if (c
== erase_char
|| c
== erase2_char
)
762 return (EC_BACKSPACE
);
764 return (EC_LINEKILL
);
767 * Collect characters in a buffer.
768 * Start with the one we have, and get more if we need them.
775 usercmd
[nch
+1] = '\0';
777 action
= ecmd_decode(usercmd
, &s
);
778 } while (action
== A_PREFIX
);
780 if (flags
& EC_NORIGHTLEFT
)
791 if (flags
& EC_NOHISTORY
)
794 * The caller says there is no history list.
795 * Reject any history-manipulation action.
806 #if TAB_COMPLETE_FILENAME
807 if (flags
& EC_NOCOMPLETE
)
810 * The caller says we don't want any filename completion cmds.
823 if ((flags
& EC_PEEK
) || action
== A_INVALID
)
826 * We're just peeking, or we didn't understand the command.
827 * Unget all the characters we read in the loop above.
828 * This does NOT include the original character that was
829 * passed in as a parameter.
833 ungetcc(usercmd
[--nch
]);