1 /* Line completion stuff for GDB, the GNU debugger.
2 Copyright (C) 2000, 2001, 2007, 2008 Free Software Foundation, Inc.
4 This file is part of GDB.
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 3 of the License, or
9 (at your option) any later version.
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program. If not, see <http://www.gnu.org/licenses/>. */
22 #include "expression.h"
23 #include "filenames.h" /* For DOSish file names. */
26 #include "cli/cli-decode.h"
28 /* FIXME: This is needed because of lookup_cmd_1 (). We should be
29 calling a hook instead so we eliminate the CLI dependency. */
32 /* Needed for rl_completer_word_break_characters() and for
33 rl_filename_completion_function. */
34 #include "readline/readline.h"
36 /* readline defines this. */
39 #include "completer.h"
41 /* Prototypes for local functions. */
43 char *line_completion_function (const char *text
, int matches
,
47 /* readline uses the word breaks for two things:
48 (1) In figuring out where to point the TEXT parameter to the
49 rl_completion_entry_function. Since we don't use TEXT for much,
50 it doesn't matter a lot what the word breaks are for this purpose, but
51 it does affect how much stuff M-? lists.
52 (2) If one of the matches contains a word break character, readline
53 will quote it. That's why we switch between
54 current_language->la_word_break_characters() and
55 gdb_completer_command_word_break_characters. I'm not sure when
56 we need this behavior (perhaps for funky characters in C++ symbols?). */
58 /* Variables which are necessary for fancy command line editing. */
60 /* When completing on command names, we remove '-' from the list of
61 word break characters, since we use it in command names. If the
62 readline library sees one in any of the current completion strings,
63 it thinks that the string needs to be quoted and automatically supplies
65 static char *gdb_completer_command_word_break_characters
=
66 " \t\n!@#$%^&*()+=|~`}{[]\"';:?/>.<,";
68 /* When completing on file names, we remove from the list of word
69 break characters any characters that are commonly used in file
70 names, such as '-', '+', '~', etc. Otherwise, readline displays
71 incorrect completion candidates. */
72 #ifdef HAVE_DOS_BASED_FILE_SYSTEM
73 /* MS-DOS and MS-Windows use colon as part of the drive spec, and most
74 programs support @foo style response files. */
75 static char *gdb_completer_file_name_break_characters
= " \t\n*|\"';?><@";
77 static char *gdb_completer_file_name_break_characters
= " \t\n*|\"';:?><";
80 /* These are used when completing on locations, which can mix file
81 names and symbol names separated by a colon. */
82 static char *gdb_completer_loc_break_characters
= " \t\n*|\"';:?><,";
84 /* Characters that can be used to quote completion strings. Note that we
85 can't include '"' because the gdb C parser treats such quoted sequences
87 static char *gdb_completer_quote_characters
= "'";
89 /* Accessor for some completer data that may interest other files. */
92 get_gdb_completer_quote_characters (void)
94 return gdb_completer_quote_characters
;
97 /* Line completion interface function for readline. */
100 readline_line_completion_function (const char *text
, int matches
)
102 return line_completion_function (text
, matches
, rl_line_buffer
, rl_point
);
105 /* This can be used for functions which don't want to complete on symbols
106 but don't want to complete on anything else either. */
108 noop_completer (char *text
, char *prefix
)
113 /* Complete on filenames. */
115 filename_completer (char *text
, char *word
)
120 int return_val_alloced
;
123 /* Small for testing. */
124 return_val_alloced
= 1;
125 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 (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 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
))
359 /* Helper for expression_completer which recursively adds field names
360 from TYPE, a struct or union type, to the array OUTPUT. This
361 function assumes that OUTPUT is correctly-sized. */
363 add_struct_fields (struct type
*type
, int *nextp
, char **output
,
364 char *fieldname
, int namelen
)
368 CHECK_TYPEDEF (type
);
369 for (i
= 0; i
< TYPE_NFIELDS (type
); ++i
)
371 if (i
< TYPE_N_BASECLASSES (type
))
372 add_struct_fields (TYPE_BASECLASS (type
, i
), nextp
, output
,
374 else if (TYPE_FIELD_NAME (type
, i
)
375 && ! strncmp (TYPE_FIELD_NAME (type
, i
), fieldname
, namelen
))
377 output
[*nextp
] = xstrdup (TYPE_FIELD_NAME (type
, i
));
383 /* Complete on expressions. Often this means completing on symbol
384 names, but some language parsers also have support for completing
387 expression_completer (char *text
, char *word
)
392 /* Perform a tentative parse of the expression, to see whether a
393 field completion is required. */
395 type
= parse_field_expression (text
, &fieldname
);
396 if (fieldname
&& type
)
400 CHECK_TYPEDEF (type
);
401 if (TYPE_CODE (type
) != TYPE_CODE_PTR
402 && TYPE_CODE (type
) != TYPE_CODE_REF
)
404 type
= TYPE_TARGET_TYPE (type
);
407 if (TYPE_CODE (type
) == TYPE_CODE_UNION
408 || TYPE_CODE (type
) == TYPE_CODE_STRUCT
)
410 int alloc
= count_struct_fields (type
);
411 int flen
= strlen (fieldname
);
413 char **result
= (char **) xmalloc ((alloc
+ 1) * sizeof (char *));
415 add_struct_fields (type
, &out
, result
, fieldname
, flen
);
421 /* Commands which complete on locations want to see the entire
424 p
> text
&& p
[-1] != ' ' && p
[-1] != '\t';
428 /* Not ideal but it is what we used to do before... */
429 return location_completer (p
, word
);
432 /* Complete on command names. Used by "help". */
434 command_completer (char *text
, char *word
)
436 return complete_on_cmdlist (cmdlist
, text
, word
);
440 /* Here are some useful test cases for completion. FIXME: These should
441 be put in the test suite. They should be tested with both M-? and TAB.
443 "show output-" "radix"
444 "show output" "-radix"
445 "p" ambiguous (commands starting with p--path, print, printf, etc.)
446 "p " ambiguous (all symbols)
447 "info t foo" no completions
448 "info t " no completions
449 "info t" ambiguous ("info target", "info terminal", etc.)
450 "info ajksdlfk" no completions
451 "info ajksdlfk " no completions
453 "info " ambiguous (all info commands)
454 "p \"a" no completions (string constant)
455 "p 'a" ambiguous (all symbols starting with a)
456 "p b-a" ambiguous (all symbols starting with a)
457 "p b-" ambiguous (all symbols)
458 "file Make" "file" (word break hard to screw up here)
459 "file ../gdb.stabs/we" "ird" (needs to not break word at slash)
462 /* Generate completions all at once. Returns a NULL-terminated array
463 of strings. Both the array and each element are allocated with
464 xmalloc. It can also return NULL if there are no completions.
466 TEXT is the caller's idea of the "word" we are looking at.
468 LINE_BUFFER is available to be looked at; it contains the entire text
469 of the line. POINT is the offset in that line of the cursor. You
470 should pretend that the line ends at POINT. */
473 complete_line (const char *text
, char *line_buffer
, int point
)
476 char *tmp_command
, *p
;
477 /* Pointer within tmp_command which corresponds to text. */
479 struct cmd_list_element
*c
, *result_list
;
481 /* Choose the default set of word break characters to break completions.
482 If we later find out that we are doing completions on command strings
483 (as opposed to strings supplied by the individual command completer
484 functions, which can be any string) then we will switch to the
485 special word break set for command strings, which leaves out the
486 '-' character used in some commands. */
488 rl_completer_word_break_characters
=
489 current_language
->la_word_break_characters();
491 /* Decide whether to complete on a list of gdb commands or on symbols. */
492 tmp_command
= (char *) alloca (point
+ 1);
495 strncpy (tmp_command
, line_buffer
, point
);
496 tmp_command
[point
] = '\0';
497 /* Since text always contains some number of characters leading up
498 to point, we can find the equivalent position in tmp_command
499 by subtracting that many characters from the end of tmp_command. */
500 word
= tmp_command
+ point
- strlen (text
);
504 /* An empty line we want to consider ambiguous; that is, it
505 could be any command. */
506 c
= (struct cmd_list_element
*) -1;
511 c
= lookup_cmd_1 (&p
, cmdlist
, &result_list
, 1);
514 /* Move p up to the next interesting thing. */
515 while (*p
== ' ' || *p
== '\t')
522 /* It is an unrecognized command. So there are no
523 possible completions. */
526 else if (c
== (struct cmd_list_element
*) -1)
530 /* lookup_cmd_1 advances p up to the first ambiguous thing, but
531 doesn't advance over that thing itself. Do so now. */
533 while (*q
&& (isalnum (*q
) || *q
== '-' || *q
== '_'))
535 if (q
!= tmp_command
+ point
)
537 /* There is something beyond the ambiguous
538 command, so there are no possible completions. For
539 example, "info t " or "info t foo" does not complete
540 to anything, because "info t" can be "info target" or
546 /* We're trying to complete on the command which was ambiguous.
547 This we can deal with. */
550 list
= complete_on_cmdlist (*result_list
->prefixlist
, p
,
555 list
= complete_on_cmdlist (cmdlist
, p
, word
);
557 /* Ensure that readline does the right thing with respect to
559 rl_completer_word_break_characters
=
560 gdb_completer_command_word_break_characters
;
565 /* We've recognized a full command. */
567 if (p
== tmp_command
+ point
)
569 /* There is no non-whitespace in the line beyond the command. */
571 if (p
[-1] == ' ' || p
[-1] == '\t')
573 /* The command is followed by whitespace; we need to complete
574 on whatever comes after command. */
577 /* It is a prefix command; what comes after it is
578 a subcommand (e.g. "info "). */
579 list
= complete_on_cmdlist (*c
->prefixlist
, p
, word
);
581 /* Ensure that readline does the right thing
582 with respect to inserting quotes. */
583 rl_completer_word_break_characters
=
584 gdb_completer_command_word_break_characters
;
588 list
= complete_on_enum (c
->enums
, p
, word
);
589 rl_completer_word_break_characters
=
590 gdb_completer_command_word_break_characters
;
594 /* It is a normal command; what comes after it is
595 completed by the command's completer function. */
596 if (c
->completer
== filename_completer
)
598 /* Many commands which want to complete on
599 file names accept several file names, as
600 in "run foo bar >>baz". So we don't want
601 to complete the entire text after the
602 command, just the last word. To this
603 end, we need to find the beginning of the
604 file name by starting at `word' and going
608 && strchr (gdb_completer_file_name_break_characters
, p
[-1]) == NULL
;
611 rl_completer_word_break_characters
=
612 gdb_completer_file_name_break_characters
;
614 else if (c
->completer
== location_completer
)
616 /* Commands which complete on locations want to
617 see the entire argument. */
620 && p
[-1] != ' ' && p
[-1] != '\t';
624 list
= (*c
->completer
) (p
, word
);
629 /* The command is not followed by whitespace; we need to
630 complete on the command itself. e.g. "p" which is a
631 command itself but also can complete to "print", "ptype"
635 /* Find the command we are completing on. */
637 while (q
> tmp_command
)
639 if (isalnum (q
[-1]) || q
[-1] == '-' || q
[-1] == '_')
645 list
= complete_on_cmdlist (result_list
, q
, word
);
647 /* Ensure that readline does the right thing
648 with respect to inserting quotes. */
649 rl_completer_word_break_characters
=
650 gdb_completer_command_word_break_characters
;
655 /* There is non-whitespace beyond the command. */
657 if (c
->prefixlist
&& !c
->allow_unknown
)
659 /* It is an unrecognized subcommand of a prefix command,
660 e.g. "info adsfkdj". */
665 list
= complete_on_enum (c
->enums
, p
, word
);
669 /* It is a normal command. */
670 if (c
->completer
== filename_completer
)
672 /* See the commentary above about the specifics
673 of file-name completion. */
676 && strchr (gdb_completer_file_name_break_characters
, p
[-1]) == NULL
;
679 rl_completer_word_break_characters
=
680 gdb_completer_file_name_break_characters
;
682 else if (c
->completer
== location_completer
)
686 && p
[-1] != ' ' && p
[-1] != '\t';
690 list
= (*c
->completer
) (p
, word
);
698 /* Generate completions one by one for the completer. Each time we are
699 called return another potential completion to the caller.
700 line_completion just completes on commands or passes the buck to the
701 command's completer function, the stuff specific to symbol completion
702 is in make_symbol_completion_list.
704 TEXT is the caller's idea of the "word" we are looking at.
706 MATCHES is the number of matches that have currently been collected from
707 calling this completion function. When zero, then we need to initialize,
708 otherwise the initialization has already taken place and we can just
709 return the next potential completion string.
711 LINE_BUFFER is available to be looked at; it contains the entire text
712 of the line. POINT is the offset in that line of the cursor. You
713 should pretend that the line ends at POINT.
715 Returns NULL if there are no more completions, else a pointer to a string
716 which is a possible completion, it is the caller's responsibility to
720 line_completion_function (const char *text
, int matches
,
721 char *line_buffer
, int point
)
723 static char **list
= (char **) NULL
; /* Cache of completions. */
724 static int index
; /* Next cached completion. */
729 /* The caller is beginning to accumulate a new set of completions, so
730 we need to find all of them now, and cache them for returning one at
731 a time on future calls. */
735 /* Free the storage used by LIST, but not by the strings inside.
736 This is because rl_complete_internal () frees the strings. */
740 list
= complete_line (text
, line_buffer
, point
);
743 /* If we found a list of potential completions during initialization then
744 dole them out one at a time. The vector of completions is NULL
745 terminated, so after returning the last one, return NULL (and continue
746 to do so) each time we are called after that, until a new list is
751 output
= list
[index
];
759 /* Can't do this because readline hasn't yet checked the word breaks
760 for figuring out whether to insert a quote. */
762 /* Make sure the word break characters are set back to normal for the
763 next time that readline tries to complete something. */
764 rl_completer_word_break_characters
=
765 current_language
->la_word_break_characters();
771 /* Skip over the possibly quoted word STR (as defined by the quote
772 characters QUOTECHARS and the the word break characters
773 BREAKCHARS). Returns pointer to the location after the "word". If
774 either QUOTECHARS or BREAKCHARS is NULL, use the same values used
778 skip_quoted_chars (char *str
, char *quotechars
, char *breakchars
)
780 char quote_char
= '\0';
783 if (quotechars
== NULL
)
784 quotechars
= gdb_completer_quote_characters
;
786 if (breakchars
== NULL
)
787 breakchars
= current_language
->la_word_break_characters();
789 for (scan
= str
; *scan
!= '\0'; scan
++)
791 if (quote_char
!= '\0')
793 /* Ignore everything until the matching close quote char. */
794 if (*scan
== quote_char
)
796 /* Found matching close quote. */
801 else if (strchr (quotechars
, *scan
))
803 /* Found start of a quoted string. */
806 else if (strchr (breakchars
, *scan
))
815 /* Skip over the possibly quoted word STR (as defined by the quote
816 characters and word break characters used by the completer).
817 Returns pointer to the location after the "word". */
820 skip_quoted (char *str
)
822 return skip_quoted_chars (str
, NULL
, NULL
);