1 /* Line completion stuff for GDB, the GNU debugger.
2 Copyright (C) 2000, 2001, 2007, 2008, 2009, 2010
3 Free Software Foundation, Inc.
5 This file is part of GDB.
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 3 of the License, or
10 (at your option) any later version.
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with this program. If not, see <http://www.gnu.org/licenses/>. */
23 #include "expression.h"
24 #include "filenames.h" /* For DOSish file names. */
26 #include "gdb_assert.h"
27 #include "exceptions.h"
29 #include "cli/cli-decode.h"
31 /* FIXME: This is needed because of lookup_cmd_1 (). We should be
32 calling a hook instead so we eliminate the CLI dependency. */
35 /* Needed for rl_completer_word_break_characters() and for
36 rl_filename_completion_function. */
37 #include "readline/readline.h"
39 /* readline defines this. */
42 #include "completer.h"
44 /* Prototypes for local functions. */
46 char *line_completion_function (const char *text
, int matches
,
50 /* readline uses the word breaks for two things:
51 (1) In figuring out where to point the TEXT parameter to the
52 rl_completion_entry_function. Since we don't use TEXT for much,
53 it doesn't matter a lot what the word breaks are for this purpose, but
54 it does affect how much stuff M-? lists.
55 (2) If one of the matches contains a word break character, readline
56 will quote it. That's why we switch between
57 current_language->la_word_break_characters() and
58 gdb_completer_command_word_break_characters. I'm not sure when
59 we need this behavior (perhaps for funky characters in C++ symbols?). */
61 /* Variables which are necessary for fancy command line editing. */
63 /* When completing on command names, we remove '-' from the list of
64 word break characters, since we use it in command names. If the
65 readline library sees one in any of the current completion strings,
66 it thinks that the string needs to be quoted and automatically supplies
68 static char *gdb_completer_command_word_break_characters
=
69 " \t\n!@#$%^&*()+=|~`}{[]\"';:?/>.<,";
71 /* When completing on file names, we remove from the list of word
72 break characters any characters that are commonly used in file
73 names, such as '-', '+', '~', etc. Otherwise, readline displays
74 incorrect completion candidates. */
75 #ifdef HAVE_DOS_BASED_FILE_SYSTEM
76 /* MS-DOS and MS-Windows use colon as part of the drive spec, and most
77 programs support @foo style response files. */
78 static char *gdb_completer_file_name_break_characters
= " \t\n*|\"';?><@";
80 static char *gdb_completer_file_name_break_characters
= " \t\n*|\"';:?><";
83 /* Characters that can be used to quote completion strings. Note that we
84 can't include '"' because the gdb C parser treats such quoted sequences
86 static char *gdb_completer_quote_characters
= "'";
88 /* Accessor for some completer data that may interest other files. */
91 get_gdb_completer_quote_characters (void)
93 return gdb_completer_quote_characters
;
96 /* Line completion interface function for readline. */
99 readline_line_completion_function (const char *text
, int matches
)
101 return line_completion_function (text
, matches
, rl_line_buffer
, rl_point
);
104 /* This can be used for functions which don't want to complete on symbols
105 but don't want to complete on anything else either. */
107 noop_completer (struct cmd_list_element
*ignore
, char *text
, char *prefix
)
112 /* Complete on filenames. */
114 filename_completer (struct cmd_list_element
*ignore
, char *text
, char *word
)
119 int return_val_alloced
;
122 /* Small for testing. */
123 return_val_alloced
= 1;
124 return_val
= (char **) xmalloc (return_val_alloced
* sizeof (char *));
131 p
= rl_filename_completion_function (text
, subsequent_name
);
132 if (return_val_used
>= return_val_alloced
)
134 return_val_alloced
*= 2;
136 (char **) xrealloc (return_val
,
137 return_val_alloced
* sizeof (char *));
141 return_val
[return_val_used
++] = p
;
144 /* We need to set subsequent_name to a non-zero value before the
145 continue line below, because otherwise, if the first file seen
146 by GDB is a backup file whose name ends in a `~', we will loop
149 /* Like emacs, don't complete on old versions. Especially useful
150 in the "source" command. */
151 if (p
[strlen (p
) - 1] == '~')
158 /* Return exactly p. */
159 return_val
[return_val_used
++] = p
;
160 else if (word
> text
)
162 /* Return some portion of p. */
163 q
= xmalloc (strlen (p
) + 5);
164 strcpy (q
, p
+ (word
- text
));
165 return_val
[return_val_used
++] = q
;
170 /* Return some of TEXT plus p. */
171 q
= xmalloc (strlen (p
) + (text
- word
) + 5);
172 strncpy (q
, word
, text
- word
);
173 q
[text
- word
] = '\0';
175 return_val
[return_val_used
++] = q
;
180 /* There is no way to do this just long enough to affect quote inserting
181 without also affecting the next completion. This should be fixed in
183 /* Ensure that readline does the right thing
184 with respect to inserting quotes. */
185 rl_completer_word_break_characters
= "";
190 /* Complete on locations, which might be of two possible forms:
196 This is intended to be used in commands that set breakpoints etc. */
198 location_completer (struct cmd_list_element
*ignore
, char *text
, char *word
)
200 int n_syms
= 0, n_files
= 0;
201 char ** fn_list
= NULL
;
205 int quoted
= *text
== '\'' || *text
== '"';
206 int quote_char
= '\0';
208 char *file_to_match
= NULL
;
209 char *symbol_start
= text
;
210 char *orig_text
= text
;
213 /* Do we have an unquoted colon, as in "break foo.c::bar"? */
214 for (p
= text
; *p
!= '\0'; ++p
)
216 if (*p
== '\\' && p
[1] == '\'')
218 else if (*p
== '\'' || *p
== '"')
222 while (*p
!= '\0' && *p
!= quote_found
)
224 if (*p
== '\\' && p
[1] == quote_found
)
229 if (*p
== quote_found
)
232 break; /* Hit the end of text. */
234 #if HAVE_DOS_BASED_FILE_SYSTEM
235 /* If we have a DOS-style absolute file name at the beginning of
236 TEXT, and the colon after the drive letter is the only colon
237 we found, pretend the colon is not there. */
238 else if (p
< text
+ 3 && *p
== ':' && p
== text
+ 1 + quoted
)
241 else if (*p
== ':' && !colon
)
244 symbol_start
= p
+ 1;
246 else if (strchr (current_language
->la_word_break_characters(), *p
))
247 symbol_start
= p
+ 1;
252 text_len
= strlen (text
);
254 /* Where is the file name? */
259 file_to_match
= (char *) xmalloc (colon
- text
+ 1);
260 strncpy (file_to_match
, text
, colon
- text
+ 1);
261 /* Remove trailing colons and quotes from the file name. */
262 for (s
= file_to_match
+ (colon
- text
);
265 if (*s
== ':' || *s
== quote_char
)
268 /* If the text includes a colon, they want completion only on a
269 symbol name after the colon. Otherwise, we need to complete on
270 symbols as well as on files. */
273 list
= make_file_symbol_completion_list (symbol_start
, word
,
275 xfree (file_to_match
);
279 list
= make_symbol_completion_list (symbol_start
, word
);
280 /* If text includes characters which cannot appear in a file
281 name, they cannot be asking for completion on files. */
283 gdb_completer_file_name_break_characters
) == text_len
)
284 fn_list
= make_source_files_completion_list (text
, text
);
287 /* How many completions do we have in both lists? */
289 for ( ; fn_list
[n_files
]; n_files
++)
292 for ( ; list
[n_syms
]; n_syms
++)
295 /* Make list[] large enough to hold both lists, then catenate
296 fn_list[] onto the end of list[]. */
297 if (n_syms
&& n_files
)
299 list
= xrealloc (list
, (n_syms
+ n_files
+ 1) * sizeof (char *));
300 memcpy (list
+ n_syms
, fn_list
, (n_files
+ 1) * sizeof (char *));
305 /* If we only have file names as possible completion, we should
306 bring them in sync with what rl_complete expects. The
307 problem is that if the user types "break /foo/b TAB", and the
308 possible completions are "/foo/bar" and "/foo/baz"
309 rl_complete expects us to return "bar" and "baz", without the
310 leading directories, as possible completions, because `word'
311 starts at the "b". But we ignore the value of `word' when we
312 call make_source_files_completion_list above (because that
313 would not DTRT when the completion results in both symbols
314 and file names), so make_source_files_completion_list returns
315 the full "/foo/bar" and "/foo/baz" strings. This produces
316 wrong results when, e.g., there's only one possible
317 completion, because rl_complete will prepend "/foo/" to each
318 candidate completion. The loop below removes that leading
320 for (n_files
= 0; fn_list
[n_files
]; n_files
++)
322 memmove (fn_list
[n_files
], fn_list
[n_files
] + (word
- text
),
323 strlen (fn_list
[n_files
]) + 1 - (word
- text
));
325 /* Return just the file-name list as the result. */
330 /* No completions at all. As the final resort, try completing
331 on the entire text as a symbol. */
332 list
= make_symbol_completion_list (orig_text
, word
);
341 /* Helper for expression_completer which recursively counts the number
342 of named fields and methods in a structure or union type. */
344 count_struct_fields (struct type
*type
)
348 CHECK_TYPEDEF (type
);
349 for (i
= 0; i
< TYPE_NFIELDS (type
); ++i
)
351 if (i
< TYPE_N_BASECLASSES (type
))
352 result
+= count_struct_fields (TYPE_BASECLASS (type
, i
));
353 else if (TYPE_FIELD_NAME (type
, i
))
357 for (i
= TYPE_NFN_FIELDS (type
) - 1; i
>= 0; --i
)
359 if (TYPE_FN_FIELDLIST_NAME (type
, i
))
366 /* Helper for expression_completer which recursively adds field and
367 method names from TYPE, a struct or union type, to the array
368 OUTPUT. This function assumes that OUTPUT is correctly-sized. */
370 add_struct_fields (struct type
*type
, int *nextp
, char **output
,
371 char *fieldname
, int namelen
)
374 int computed_type_name
= 0;
375 char *type_name
= NULL
;
377 CHECK_TYPEDEF (type
);
378 for (i
= 0; i
< TYPE_NFIELDS (type
); ++i
)
380 if (i
< TYPE_N_BASECLASSES (type
))
381 add_struct_fields (TYPE_BASECLASS (type
, i
), nextp
, output
,
383 else if (TYPE_FIELD_NAME (type
, i
)
384 && ! strncmp (TYPE_FIELD_NAME (type
, i
), fieldname
, namelen
))
386 output
[*nextp
] = xstrdup (TYPE_FIELD_NAME (type
, i
));
391 for (i
= TYPE_NFN_FIELDS (type
) - 1; i
>= 0; --i
)
393 char *name
= TYPE_FN_FIELDLIST_NAME (type
, i
);
395 if (name
&& ! strncmp (name
, fieldname
, namelen
))
397 if (!computed_type_name
)
399 type_name
= type_name_no_tag (type
);
400 computed_type_name
= 1;
402 /* Omit constructors from the completion list. */
403 if (!type_name
|| strcmp (type_name
, name
))
405 output
[*nextp
] = xstrdup (name
);
412 /* Complete on expressions. Often this means completing on symbol
413 names, but some language parsers also have support for completing
416 expression_completer (struct cmd_list_element
*ignore
, char *text
, char *word
)
418 struct type
*type
= NULL
;
420 volatile struct gdb_exception except
;
422 /* Perform a tentative parse of the expression, to see whether a
423 field completion is required. */
425 TRY_CATCH (except
, RETURN_MASK_ERROR
)
427 type
= parse_field_expression (text
, &fieldname
);
429 if (except
.reason
< 0)
431 if (fieldname
&& type
)
435 CHECK_TYPEDEF (type
);
436 if (TYPE_CODE (type
) != TYPE_CODE_PTR
437 && TYPE_CODE (type
) != TYPE_CODE_REF
)
439 type
= TYPE_TARGET_TYPE (type
);
442 if (TYPE_CODE (type
) == TYPE_CODE_UNION
443 || TYPE_CODE (type
) == TYPE_CODE_STRUCT
)
445 int alloc
= count_struct_fields (type
);
446 int flen
= strlen (fieldname
);
448 char **result
= (char **) xmalloc ((alloc
+ 1) * sizeof (char *));
450 add_struct_fields (type
, &out
, result
, fieldname
, flen
);
458 /* Commands which complete on locations want to see the entire
461 p
> text
&& p
[-1] != ' ' && p
[-1] != '\t';
465 /* Not ideal but it is what we used to do before... */
466 return location_completer (ignore
, p
, word
);
469 /* Here are some useful test cases for completion. FIXME: These should
470 be put in the test suite. They should be tested with both M-? and TAB.
472 "show output-" "radix"
473 "show output" "-radix"
474 "p" ambiguous (commands starting with p--path, print, printf, etc.)
475 "p " ambiguous (all symbols)
476 "info t foo" no completions
477 "info t " no completions
478 "info t" ambiguous ("info target", "info terminal", etc.)
479 "info ajksdlfk" no completions
480 "info ajksdlfk " no completions
482 "info " ambiguous (all info commands)
483 "p \"a" no completions (string constant)
484 "p 'a" ambiguous (all symbols starting with a)
485 "p b-a" ambiguous (all symbols starting with a)
486 "p b-" ambiguous (all symbols)
487 "file Make" "file" (word break hard to screw up here)
488 "file ../gdb.stabs/we" "ird" (needs to not break word at slash)
497 complete_line_internal_reason
;
500 /* Internal function used to handle completions.
503 TEXT is the caller's idea of the "word" we are looking at.
505 LINE_BUFFER is available to be looked at; it contains the entire text
506 of the line. POINT is the offset in that line of the cursor. You
507 should pretend that the line ends at POINT.
509 REASON is of type complete_line_internal_reason.
511 If REASON is handle_brkchars:
512 Preliminary phase, called by gdb_completion_word_break_characters function,
513 is used to determine the correct set of chars that are word delimiters
514 depending on the current command in line_buffer.
515 No completion list should be generated; the return value should be NULL.
516 This is checked by an assertion in that function.
518 If REASON is handle_completions:
519 Main phase, called by complete_line function, is used to get the list
520 of posible completions.
522 If REASON is handle_help:
523 Special case when completing a 'help' command. In this case,
524 once sub-command completions are exhausted, we simply return NULL.
528 complete_line_internal (const char *text
, char *line_buffer
, int point
,
529 complete_line_internal_reason reason
)
532 char *tmp_command
, *p
;
533 /* Pointer within tmp_command which corresponds to text. */
535 struct cmd_list_element
*c
, *result_list
;
537 /* Choose the default set of word break characters to break completions.
538 If we later find out that we are doing completions on command strings
539 (as opposed to strings supplied by the individual command completer
540 functions, which can be any string) then we will switch to the
541 special word break set for command strings, which leaves out the
542 '-' character used in some commands. */
543 rl_completer_word_break_characters
=
544 current_language
->la_word_break_characters();
546 /* Decide whether to complete on a list of gdb commands or on symbols. */
547 tmp_command
= (char *) alloca (point
+ 1);
550 strncpy (tmp_command
, line_buffer
, point
);
551 tmp_command
[point
] = '\0';
552 /* Since text always contains some number of characters leading up
553 to point, we can find the equivalent position in tmp_command
554 by subtracting that many characters from the end of tmp_command. */
555 word
= tmp_command
+ point
- strlen (text
);
559 /* An empty line we want to consider ambiguous; that is, it
560 could be any command. */
561 c
= (struct cmd_list_element
*) -1;
566 c
= lookup_cmd_1 (&p
, cmdlist
, &result_list
, 1);
569 /* Move p up to the next interesting thing. */
570 while (*p
== ' ' || *p
== '\t')
577 /* It is an unrecognized command. So there are no
578 possible completions. */
581 else if (c
== (struct cmd_list_element
*) -1)
585 /* lookup_cmd_1 advances p up to the first ambiguous thing, but
586 doesn't advance over that thing itself. Do so now. */
588 while (*q
&& (isalnum (*q
) || *q
== '-' || *q
== '_'))
590 if (q
!= tmp_command
+ point
)
592 /* There is something beyond the ambiguous
593 command, so there are no possible completions. For
594 example, "info t " or "info t foo" does not complete
595 to anything, because "info t" can be "info target" or
601 /* We're trying to complete on the command which was ambiguous.
602 This we can deal with. */
605 if (reason
!= handle_brkchars
)
606 list
= complete_on_cmdlist (*result_list
->prefixlist
, p
,
611 if (reason
!= handle_brkchars
)
612 list
= complete_on_cmdlist (cmdlist
, p
, word
);
614 /* Ensure that readline does the right thing with respect to
616 rl_completer_word_break_characters
=
617 gdb_completer_command_word_break_characters
;
622 /* We've recognized a full command. */
624 if (p
== tmp_command
+ point
)
626 /* There is no non-whitespace in the line beyond the command. */
628 if (p
[-1] == ' ' || p
[-1] == '\t')
630 /* The command is followed by whitespace; we need to complete
631 on whatever comes after command. */
634 /* It is a prefix command; what comes after it is
635 a subcommand (e.g. "info "). */
636 if (reason
!= handle_brkchars
)
637 list
= complete_on_cmdlist (*c
->prefixlist
, p
, word
);
639 /* Ensure that readline does the right thing
640 with respect to inserting quotes. */
641 rl_completer_word_break_characters
=
642 gdb_completer_command_word_break_characters
;
644 else if (reason
== handle_help
)
648 if (reason
!= handle_brkchars
)
649 list
= complete_on_enum (c
->enums
, p
, word
);
650 rl_completer_word_break_characters
=
651 gdb_completer_command_word_break_characters
;
655 /* It is a normal command; what comes after it is
656 completed by the command's completer function. */
657 if (c
->completer
== filename_completer
)
659 /* Many commands which want to complete on
660 file names accept several file names, as
661 in "run foo bar >>baz". So we don't want
662 to complete the entire text after the
663 command, just the last word. To this
664 end, we need to find the beginning of the
665 file name by starting at `word' and going
669 && strchr (gdb_completer_file_name_break_characters
, p
[-1]) == NULL
;
672 rl_completer_word_break_characters
=
673 gdb_completer_file_name_break_characters
;
675 else if (c
->completer
== location_completer
)
677 /* Commands which complete on locations want to
678 see the entire argument. */
681 && p
[-1] != ' ' && p
[-1] != '\t';
685 if (reason
!= handle_brkchars
&& c
->completer
!= NULL
)
686 list
= (*c
->completer
) (c
, p
, word
);
691 /* The command is not followed by whitespace; we need to
692 complete on the command itself. e.g. "p" which is a
693 command itself but also can complete to "print", "ptype"
697 /* Find the command we are completing on. */
699 while (q
> tmp_command
)
701 if (isalnum (q
[-1]) || q
[-1] == '-' || q
[-1] == '_')
707 if (reason
!= handle_brkchars
)
708 list
= complete_on_cmdlist (result_list
, q
, word
);
710 /* Ensure that readline does the right thing
711 with respect to inserting quotes. */
712 rl_completer_word_break_characters
=
713 gdb_completer_command_word_break_characters
;
716 else if (reason
== handle_help
)
720 /* There is non-whitespace beyond the command. */
722 if (c
->prefixlist
&& !c
->allow_unknown
)
724 /* It is an unrecognized subcommand of a prefix command,
725 e.g. "info adsfkdj". */
730 if (reason
!= handle_brkchars
)
731 list
= complete_on_enum (c
->enums
, p
, word
);
735 /* It is a normal command. */
736 if (c
->completer
== filename_completer
)
738 /* See the commentary above about the specifics
739 of file-name completion. */
742 && strchr (gdb_completer_file_name_break_characters
, p
[-1]) == NULL
;
745 rl_completer_word_break_characters
=
746 gdb_completer_file_name_break_characters
;
748 else if (c
->completer
== location_completer
)
752 && p
[-1] != ' ' && p
[-1] != '\t';
756 if (reason
!= handle_brkchars
&& c
->completer
!= NULL
)
757 list
= (*c
->completer
) (c
, p
, word
);
764 /* Generate completions all at once. Returns a NULL-terminated array
765 of strings. Both the array and each element are allocated with
766 xmalloc. It can also return NULL if there are no completions.
768 TEXT is the caller's idea of the "word" we are looking at.
770 LINE_BUFFER is available to be looked at; it contains the entire text
773 POINT is the offset in that line of the cursor. You
774 should pretend that the line ends at POINT. */
777 complete_line (const char *text
, char *line_buffer
, int point
)
779 return complete_line_internal (text
, line_buffer
, point
, handle_completions
);
782 /* Complete on command names. Used by "help". */
784 command_completer (struct cmd_list_element
*ignore
, char *text
, char *word
)
786 return complete_line_internal (word
, text
, strlen (text
), handle_help
);
789 /* Get the list of chars that are considered as word breaks
790 for the current command. */
793 gdb_completion_word_break_characters (void)
797 list
= complete_line_internal (rl_line_buffer
, rl_line_buffer
, rl_point
,
799 gdb_assert (list
== NULL
);
800 return rl_completer_word_break_characters
;
803 /* Generate completions one by one for the completer. Each time we are
804 called return another potential completion to the caller.
805 line_completion just completes on commands or passes the buck to the
806 command's completer function, the stuff specific to symbol completion
807 is in make_symbol_completion_list.
809 TEXT is the caller's idea of the "word" we are looking at.
811 MATCHES is the number of matches that have currently been collected from
812 calling this completion function. When zero, then we need to initialize,
813 otherwise the initialization has already taken place and we can just
814 return the next potential completion string.
816 LINE_BUFFER is available to be looked at; it contains the entire text
817 of the line. POINT is the offset in that line of the cursor. You
818 should pretend that the line ends at POINT.
820 Returns NULL if there are no more completions, else a pointer to a string
821 which is a possible completion, it is the caller's responsibility to
825 line_completion_function (const char *text
, int matches
,
826 char *line_buffer
, int point
)
828 static char **list
= (char **) NULL
; /* Cache of completions. */
829 static int index
; /* Next cached completion. */
834 /* The caller is beginning to accumulate a new set of completions, so
835 we need to find all of them now, and cache them for returning one at
836 a time on future calls. */
840 /* Free the storage used by LIST, but not by the strings inside.
841 This is because rl_complete_internal () frees the strings.
842 As complete_line may abort by calling `error' clear LIST now. */
847 list
= complete_line (text
, line_buffer
, point
);
850 /* If we found a list of potential completions during initialization then
851 dole them out one at a time. The vector of completions is NULL
852 terminated, so after returning the last one, return NULL (and continue
853 to do so) each time we are called after that, until a new list is
858 output
= list
[index
];
866 /* Can't do this because readline hasn't yet checked the word breaks
867 for figuring out whether to insert a quote. */
869 /* Make sure the word break characters are set back to normal for the
870 next time that readline tries to complete something. */
871 rl_completer_word_break_characters
=
872 current_language
->la_word_break_characters();
878 /* Skip over the possibly quoted word STR (as defined by the quote
879 characters QUOTECHARS and the the word break characters
880 BREAKCHARS). Returns pointer to the location after the "word". If
881 either QUOTECHARS or BREAKCHARS is NULL, use the same values used
885 skip_quoted_chars (char *str
, char *quotechars
, char *breakchars
)
887 char quote_char
= '\0';
890 if (quotechars
== NULL
)
891 quotechars
= gdb_completer_quote_characters
;
893 if (breakchars
== NULL
)
894 breakchars
= current_language
->la_word_break_characters();
896 for (scan
= str
; *scan
!= '\0'; scan
++)
898 if (quote_char
!= '\0')
900 /* Ignore everything until the matching close quote char. */
901 if (*scan
== quote_char
)
903 /* Found matching close quote. */
908 else if (strchr (quotechars
, *scan
))
910 /* Found start of a quoted string. */
913 else if (strchr (breakchars
, *scan
))
922 /* Skip over the possibly quoted word STR (as defined by the quote
923 characters and word break characters used by the completer).
924 Returns pointer to the location after the "word". */
927 skip_quoted (char *str
)
929 return skip_quoted_chars (str
, NULL
, NULL
);