| 1 | /* Line completion stuff for GDB, the GNU debugger. |
| 2 | Copyright 2000, 2001 Free Software Foundation, Inc. |
| 3 | |
| 4 | This file is part of GDB. |
| 5 | |
| 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 2 of the License, or |
| 9 | (at your option) any later version. |
| 10 | |
| 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. |
| 15 | |
| 16 | You should have received a copy of the GNU General Public License |
| 17 | along with this program; if not, write to the Free Software |
| 18 | Foundation, Inc., 59 Temple Place - Suite 330, |
| 19 | Boston, MA 02111-1307, USA. */ |
| 20 | |
| 21 | #include "defs.h" |
| 22 | #include "symtab.h" |
| 23 | #include "gdbtypes.h" |
| 24 | #include "expression.h" |
| 25 | |
| 26 | /* FIXME: This is needed because of lookup_cmd_1(). |
| 27 | We should be calling a hook instead so we eliminate the CLI dependency. */ |
| 28 | #include "gdbcmd.h" |
| 29 | |
| 30 | /* Needed for rl_completer_word_break_characters() */ |
| 31 | #include <readline/readline.h> |
| 32 | |
| 33 | /* readline defines this. */ |
| 34 | #undef savestring |
| 35 | |
| 36 | #include "completer.h" |
| 37 | |
| 38 | /* Prototypes for local functions */ |
| 39 | |
| 40 | /* readline uses the word breaks for two things: |
| 41 | (1) In figuring out where to point the TEXT parameter to the |
| 42 | rl_completion_entry_function. Since we don't use TEXT for much, |
| 43 | it doesn't matter a lot what the word breaks are for this purpose, but |
| 44 | it does affect how much stuff M-? lists. |
| 45 | (2) If one of the matches contains a word break character, readline |
| 46 | will quote it. That's why we switch between |
| 47 | gdb_completer_word_break_characters and |
| 48 | gdb_completer_command_word_break_characters. I'm not sure when |
| 49 | we need this behavior (perhaps for funky characters in C++ symbols?). */ |
| 50 | |
| 51 | /* Variables which are necessary for fancy command line editing. */ |
| 52 | static char *gdb_completer_word_break_characters = |
| 53 | " \t\n!@#$%^&*()+=|~`}{[]\"';:?/>.<,-"; |
| 54 | |
| 55 | /* When completing on command names, we remove '-' from the list of |
| 56 | word break characters, since we use it in command names. If the |
| 57 | readline library sees one in any of the current completion strings, |
| 58 | it thinks that the string needs to be quoted and automatically supplies |
| 59 | a leading quote. */ |
| 60 | static char *gdb_completer_command_word_break_characters = |
| 61 | " \t\n!@#$%^&*()+=|~`}{[]\"';:?/>.<,"; |
| 62 | |
| 63 | /* When completing on file names, we remove from the list of word |
| 64 | break characters any characters that are commonly used in file |
| 65 | names, such as '-', '+', '~', etc. Otherwise, readline displays |
| 66 | incorrect completion candidates. */ |
| 67 | #ifdef HAVE_DOS_BASED_FILE_SYSTEM |
| 68 | /* MS-DOS and MS-Windows use colon as part of the drive spec, and most |
| 69 | programs support @foo style response files. */ |
| 70 | static char *gdb_completer_file_name_break_characters = " \t\n*|\"';?><@"; |
| 71 | #else |
| 72 | static char *gdb_completer_file_name_break_characters = " \t\n*|\"';:?><"; |
| 73 | #endif |
| 74 | |
| 75 | /* Characters that can be used to quote completion strings. Note that we |
| 76 | can't include '"' because the gdb C parser treats such quoted sequences |
| 77 | as strings. */ |
| 78 | static char *gdb_completer_quote_characters = "'"; |
| 79 | \f |
| 80 | /* Accessor for some completer data that may interest other files. */ |
| 81 | |
| 82 | char * |
| 83 | get_gdb_completer_word_break_characters (void) |
| 84 | { |
| 85 | return gdb_completer_word_break_characters; |
| 86 | } |
| 87 | |
| 88 | char * |
| 89 | get_gdb_completer_quote_characters (void) |
| 90 | { |
| 91 | return gdb_completer_quote_characters; |
| 92 | } |
| 93 | |
| 94 | /* Complete on filenames. */ |
| 95 | char ** |
| 96 | filename_completer (char *text, char *word) |
| 97 | { |
| 98 | /* From readline. */ |
| 99 | extern char *filename_completion_function (char *, int); |
| 100 | int subsequent_name; |
| 101 | char **return_val; |
| 102 | int return_val_used; |
| 103 | int return_val_alloced; |
| 104 | |
| 105 | return_val_used = 0; |
| 106 | /* Small for testing. */ |
| 107 | return_val_alloced = 1; |
| 108 | return_val = (char **) xmalloc (return_val_alloced * sizeof (char *)); |
| 109 | |
| 110 | subsequent_name = 0; |
| 111 | while (1) |
| 112 | { |
| 113 | char *p; |
| 114 | p = filename_completion_function (text, subsequent_name); |
| 115 | if (return_val_used >= return_val_alloced) |
| 116 | { |
| 117 | return_val_alloced *= 2; |
| 118 | return_val = |
| 119 | (char **) xrealloc (return_val, |
| 120 | return_val_alloced * sizeof (char *)); |
| 121 | } |
| 122 | if (p == NULL) |
| 123 | { |
| 124 | return_val[return_val_used++] = p; |
| 125 | break; |
| 126 | } |
| 127 | /* We need to set subsequent_name to a non-zero value before the |
| 128 | continue line below, because otherwise, if the first file seen |
| 129 | by GDB is a backup file whose name ends in a `~', we will loop |
| 130 | indefinitely. */ |
| 131 | subsequent_name = 1; |
| 132 | /* Like emacs, don't complete on old versions. Especially useful |
| 133 | in the "source" command. */ |
| 134 | if (p[strlen (p) - 1] == '~') |
| 135 | continue; |
| 136 | |
| 137 | { |
| 138 | char *q; |
| 139 | if (word == text) |
| 140 | /* Return exactly p. */ |
| 141 | return_val[return_val_used++] = p; |
| 142 | else if (word > text) |
| 143 | { |
| 144 | /* Return some portion of p. */ |
| 145 | q = xmalloc (strlen (p) + 5); |
| 146 | strcpy (q, p + (word - text)); |
| 147 | return_val[return_val_used++] = q; |
| 148 | xfree (p); |
| 149 | } |
| 150 | else |
| 151 | { |
| 152 | /* Return some of TEXT plus p. */ |
| 153 | q = xmalloc (strlen (p) + (text - word) + 5); |
| 154 | strncpy (q, word, text - word); |
| 155 | q[text - word] = '\0'; |
| 156 | strcat (q, p); |
| 157 | return_val[return_val_used++] = q; |
| 158 | xfree (p); |
| 159 | } |
| 160 | } |
| 161 | } |
| 162 | #if 0 |
| 163 | /* There is no way to do this just long enough to affect quote inserting |
| 164 | without also affecting the next completion. This should be fixed in |
| 165 | readline. FIXME. */ |
| 166 | /* Insure that readline does the right thing |
| 167 | with respect to inserting quotes. */ |
| 168 | rl_completer_word_break_characters = ""; |
| 169 | #endif |
| 170 | return return_val; |
| 171 | } |
| 172 | |
| 173 | /* Here are some useful test cases for completion. FIXME: These should |
| 174 | be put in the test suite. They should be tested with both M-? and TAB. |
| 175 | |
| 176 | "show output-" "radix" |
| 177 | "show output" "-radix" |
| 178 | "p" ambiguous (commands starting with p--path, print, printf, etc.) |
| 179 | "p " ambiguous (all symbols) |
| 180 | "info t foo" no completions |
| 181 | "info t " no completions |
| 182 | "info t" ambiguous ("info target", "info terminal", etc.) |
| 183 | "info ajksdlfk" no completions |
| 184 | "info ajksdlfk " no completions |
| 185 | "info" " " |
| 186 | "info " ambiguous (all info commands) |
| 187 | "p \"a" no completions (string constant) |
| 188 | "p 'a" ambiguous (all symbols starting with a) |
| 189 | "p b-a" ambiguous (all symbols starting with a) |
| 190 | "p b-" ambiguous (all symbols) |
| 191 | "file Make" "file" (word break hard to screw up here) |
| 192 | "file ../gdb.stabs/we" "ird" (needs to not break word at slash) |
| 193 | */ |
| 194 | |
| 195 | /* Generate completions one by one for the completer. Each time we are |
| 196 | called return another potential completion to the caller. |
| 197 | line_completion just completes on commands or passes the buck to the |
| 198 | command's completer function, the stuff specific to symbol completion |
| 199 | is in make_symbol_completion_list. |
| 200 | |
| 201 | TEXT is the caller's idea of the "word" we are looking at. |
| 202 | |
| 203 | MATCHES is the number of matches that have currently been collected from |
| 204 | calling this completion function. When zero, then we need to initialize, |
| 205 | otherwise the initialization has already taken place and we can just |
| 206 | return the next potential completion string. |
| 207 | |
| 208 | LINE_BUFFER is available to be looked at; it contains the entire text |
| 209 | of the line. POINT is the offset in that line of the cursor. You |
| 210 | should pretend that the line ends at POINT. |
| 211 | |
| 212 | Returns NULL if there are no more completions, else a pointer to a string |
| 213 | which is a possible completion, it is the caller's responsibility to |
| 214 | free the string. */ |
| 215 | |
| 216 | char * |
| 217 | line_completion_function (char *text, int matches, char *line_buffer, int point) |
| 218 | { |
| 219 | static char **list = (char **) NULL; /* Cache of completions */ |
| 220 | static int index; /* Next cached completion */ |
| 221 | char *output = NULL; |
| 222 | char *tmp_command, *p; |
| 223 | /* Pointer within tmp_command which corresponds to text. */ |
| 224 | char *word; |
| 225 | struct cmd_list_element *c, *result_list; |
| 226 | |
| 227 | if (matches == 0) |
| 228 | { |
| 229 | /* The caller is beginning to accumulate a new set of completions, so |
| 230 | we need to find all of them now, and cache them for returning one at |
| 231 | a time on future calls. */ |
| 232 | |
| 233 | if (list) |
| 234 | { |
| 235 | /* Free the storage used by LIST, but not by the strings inside. |
| 236 | This is because rl_complete_internal () frees the strings. */ |
| 237 | xfree (list); |
| 238 | } |
| 239 | list = 0; |
| 240 | index = 0; |
| 241 | |
| 242 | /* Choose the default set of word break characters to break completions. |
| 243 | If we later find out that we are doing completions on command strings |
| 244 | (as opposed to strings supplied by the individual command completer |
| 245 | functions, which can be any string) then we will switch to the |
| 246 | special word break set for command strings, which leaves out the |
| 247 | '-' character used in some commands. */ |
| 248 | |
| 249 | rl_completer_word_break_characters = |
| 250 | gdb_completer_word_break_characters; |
| 251 | |
| 252 | /* Decide whether to complete on a list of gdb commands or on symbols. */ |
| 253 | tmp_command = (char *) alloca (point + 1); |
| 254 | p = tmp_command; |
| 255 | |
| 256 | strncpy (tmp_command, line_buffer, point); |
| 257 | tmp_command[point] = '\0'; |
| 258 | /* Since text always contains some number of characters leading up |
| 259 | to point, we can find the equivalent position in tmp_command |
| 260 | by subtracting that many characters from the end of tmp_command. */ |
| 261 | word = tmp_command + point - strlen (text); |
| 262 | |
| 263 | if (point == 0) |
| 264 | { |
| 265 | /* An empty line we want to consider ambiguous; that is, it |
| 266 | could be any command. */ |
| 267 | c = (struct cmd_list_element *) -1; |
| 268 | result_list = 0; |
| 269 | } |
| 270 | else |
| 271 | { |
| 272 | c = lookup_cmd_1 (&p, cmdlist, &result_list, 1); |
| 273 | } |
| 274 | |
| 275 | /* Move p up to the next interesting thing. */ |
| 276 | while (*p == ' ' || *p == '\t') |
| 277 | { |
| 278 | p++; |
| 279 | } |
| 280 | |
| 281 | if (!c) |
| 282 | { |
| 283 | /* It is an unrecognized command. So there are no |
| 284 | possible completions. */ |
| 285 | list = NULL; |
| 286 | } |
| 287 | else if (c == (struct cmd_list_element *) -1) |
| 288 | { |
| 289 | char *q; |
| 290 | |
| 291 | /* lookup_cmd_1 advances p up to the first ambiguous thing, but |
| 292 | doesn't advance over that thing itself. Do so now. */ |
| 293 | q = p; |
| 294 | while (*q && (isalnum (*q) || *q == '-' || *q == '_')) |
| 295 | ++q; |
| 296 | if (q != tmp_command + point) |
| 297 | { |
| 298 | /* There is something beyond the ambiguous |
| 299 | command, so there are no possible completions. For |
| 300 | example, "info t " or "info t foo" does not complete |
| 301 | to anything, because "info t" can be "info target" or |
| 302 | "info terminal". */ |
| 303 | list = NULL; |
| 304 | } |
| 305 | else |
| 306 | { |
| 307 | /* We're trying to complete on the command which was ambiguous. |
| 308 | This we can deal with. */ |
| 309 | if (result_list) |
| 310 | { |
| 311 | list = complete_on_cmdlist (*result_list->prefixlist, p, |
| 312 | word); |
| 313 | } |
| 314 | else |
| 315 | { |
| 316 | list = complete_on_cmdlist (cmdlist, p, word); |
| 317 | } |
| 318 | /* Insure that readline does the right thing with respect to |
| 319 | inserting quotes. */ |
| 320 | rl_completer_word_break_characters = |
| 321 | gdb_completer_command_word_break_characters; |
| 322 | } |
| 323 | } |
| 324 | else |
| 325 | { |
| 326 | /* We've recognized a full command. */ |
| 327 | |
| 328 | if (p == tmp_command + point) |
| 329 | { |
| 330 | /* There is no non-whitespace in the line beyond the command. */ |
| 331 | |
| 332 | if (p[-1] == ' ' || p[-1] == '\t') |
| 333 | { |
| 334 | /* The command is followed by whitespace; we need to complete |
| 335 | on whatever comes after command. */ |
| 336 | if (c->prefixlist) |
| 337 | { |
| 338 | /* It is a prefix command; what comes after it is |
| 339 | a subcommand (e.g. "info "). */ |
| 340 | list = complete_on_cmdlist (*c->prefixlist, p, word); |
| 341 | |
| 342 | /* Insure that readline does the right thing |
| 343 | with respect to inserting quotes. */ |
| 344 | rl_completer_word_break_characters = |
| 345 | gdb_completer_command_word_break_characters; |
| 346 | } |
| 347 | else if (c->enums) |
| 348 | { |
| 349 | list = complete_on_enum (c->enums, p, word); |
| 350 | rl_completer_word_break_characters = |
| 351 | gdb_completer_command_word_break_characters; |
| 352 | } |
| 353 | else |
| 354 | { |
| 355 | /* It is a normal command; what comes after it is |
| 356 | completed by the command's completer function. */ |
| 357 | if (c->completer == filename_completer) |
| 358 | { |
| 359 | /* Many commands which want to complete on |
| 360 | file names accept several file names, as |
| 361 | in "run foo bar >>baz". So we don't want |
| 362 | to complete the entire text after the |
| 363 | command, just the last word. To this |
| 364 | end, we need to find the beginning of the |
| 365 | file name starting at `word' and going |
| 366 | backwards. */ |
| 367 | for (p = word; |
| 368 | p > tmp_command |
| 369 | && strchr (gdb_completer_file_name_break_characters, p[-1]) == NULL; |
| 370 | p--) |
| 371 | ; |
| 372 | rl_completer_word_break_characters = |
| 373 | gdb_completer_file_name_break_characters; |
| 374 | } |
| 375 | list = (*c->completer) (p, word); |
| 376 | } |
| 377 | } |
| 378 | else |
| 379 | { |
| 380 | /* The command is not followed by whitespace; we need to |
| 381 | complete on the command itself. e.g. "p" which is a |
| 382 | command itself but also can complete to "print", "ptype" |
| 383 | etc. */ |
| 384 | char *q; |
| 385 | |
| 386 | /* Find the command we are completing on. */ |
| 387 | q = p; |
| 388 | while (q > tmp_command) |
| 389 | { |
| 390 | if (isalnum (q[-1]) || q[-1] == '-' || q[-1] == '_') |
| 391 | --q; |
| 392 | else |
| 393 | break; |
| 394 | } |
| 395 | |
| 396 | list = complete_on_cmdlist (result_list, q, word); |
| 397 | |
| 398 | /* Insure that readline does the right thing |
| 399 | with respect to inserting quotes. */ |
| 400 | rl_completer_word_break_characters = |
| 401 | gdb_completer_command_word_break_characters; |
| 402 | } |
| 403 | } |
| 404 | else |
| 405 | { |
| 406 | /* There is non-whitespace beyond the command. */ |
| 407 | |
| 408 | if (c->prefixlist && !c->allow_unknown) |
| 409 | { |
| 410 | /* It is an unrecognized subcommand of a prefix command, |
| 411 | e.g. "info adsfkdj". */ |
| 412 | list = NULL; |
| 413 | } |
| 414 | else if (c->enums) |
| 415 | { |
| 416 | list = complete_on_enum (c->enums, p, word); |
| 417 | } |
| 418 | else |
| 419 | { |
| 420 | /* It is a normal command. */ |
| 421 | if (c->completer == filename_completer) |
| 422 | { |
| 423 | /* See the commentary above about the specifics |
| 424 | of file-name completion. */ |
| 425 | for (p = word; |
| 426 | p > tmp_command |
| 427 | && strchr (gdb_completer_file_name_break_characters, p[-1]) == NULL; |
| 428 | p--) |
| 429 | ; |
| 430 | rl_completer_word_break_characters = |
| 431 | gdb_completer_file_name_break_characters; |
| 432 | } |
| 433 | list = (*c->completer) (p, word); |
| 434 | } |
| 435 | } |
| 436 | } |
| 437 | } |
| 438 | |
| 439 | /* If we found a list of potential completions during initialization then |
| 440 | dole them out one at a time. The vector of completions is NULL |
| 441 | terminated, so after returning the last one, return NULL (and continue |
| 442 | to do so) each time we are called after that, until a new list is |
| 443 | available. */ |
| 444 | |
| 445 | if (list) |
| 446 | { |
| 447 | output = list[index]; |
| 448 | if (output) |
| 449 | { |
| 450 | index++; |
| 451 | } |
| 452 | } |
| 453 | |
| 454 | #if 0 |
| 455 | /* Can't do this because readline hasn't yet checked the word breaks |
| 456 | for figuring out whether to insert a quote. */ |
| 457 | if (output == NULL) |
| 458 | /* Make sure the word break characters are set back to normal for the |
| 459 | next time that readline tries to complete something. */ |
| 460 | rl_completer_word_break_characters = |
| 461 | gdb_completer_word_break_characters; |
| 462 | #endif |
| 463 | |
| 464 | return (output); |
| 465 | } |
| 466 | /* Skip over a possibly quoted word (as defined by the quote characters |
| 467 | and word break characters the completer uses). Returns pointer to the |
| 468 | location after the "word". */ |
| 469 | |
| 470 | char * |
| 471 | skip_quoted (char *str) |
| 472 | { |
| 473 | char quote_char = '\0'; |
| 474 | char *scan; |
| 475 | |
| 476 | for (scan = str; *scan != '\0'; scan++) |
| 477 | { |
| 478 | if (quote_char != '\0') |
| 479 | { |
| 480 | /* Ignore everything until the matching close quote char */ |
| 481 | if (*scan == quote_char) |
| 482 | { |
| 483 | /* Found matching close quote. */ |
| 484 | scan++; |
| 485 | break; |
| 486 | } |
| 487 | } |
| 488 | else if (strchr (gdb_completer_quote_characters, *scan)) |
| 489 | { |
| 490 | /* Found start of a quoted string. */ |
| 491 | quote_char = *scan; |
| 492 | } |
| 493 | else if (strchr (gdb_completer_word_break_characters, *scan)) |
| 494 | { |
| 495 | break; |
| 496 | } |
| 497 | } |
| 498 | return (scan); |
| 499 | } |
| 500 | |