1/* Top level stuff for GDB, the GNU debugger. 2 Copyright 1999, 2000, 2001, 2002, 2004 Free Software Foundation, Inc. 3 Written by Elena Zannoni <ezannoni@cygnus.com> of Cygnus Solutions. 4 5 This file is part of GDB. 6 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 2 of the License, or 10 (at your option) any later version. 11 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. 16 17 You should have received a copy of the GNU General Public License 18 along with this program; if not, write to the Free Software 19 Foundation, Inc., 59 Temple Place - Suite 330, 20 Boston, MA 02111-1307, USA. */ 21 22#include "defs.h" 23#include "top.h" 24#include "inferior.h" 25#include "target.h" 26#include "terminal.h" /* for job_control */ 27#include "event-loop.h" 28#include "event-top.h" 29#include "interps.h" 30#include <signal.h> 31 32/* For dont_repeat() */ 33#include "gdbcmd.h" 34 35/* readline include files */ 36#include "readline/readline.h" 37#include "readline/history.h" 38 39/* readline defines this. */ 40#undef savestring 41 42static void rl_callback_read_char_wrapper (gdb_client_data client_data); 43static void command_line_handler (char *rl); 44static void command_line_handler_continuation (struct continuation_arg *arg); 45static void change_line_handler (void); 46static void change_annotation_level (void); 47static void command_handler (char *command); 48static void async_do_nothing (gdb_client_data arg); 49static void async_disconnect (gdb_client_data arg); 50static void async_stop_sig (gdb_client_data arg); 51static void async_float_handler (gdb_client_data arg); 52 53/* Signal handlers. */ 54static void handle_sigquit (int sig); 55static void handle_sighup (int sig); 56static void handle_sigfpe (int sig); 57#if defined(SIGWINCH) && defined(SIGWINCH_HANDLER) 58static void handle_sigwinch (int sig); 59#endif 60 61/* Functions to be invoked by the event loop in response to 62 signals. */ 63static void async_do_nothing (gdb_client_data); 64static void async_disconnect (gdb_client_data); 65static void async_float_handler (gdb_client_data); 66static void async_stop_sig (gdb_client_data); 67 68/* Readline offers an alternate interface, via callback 69 functions. These are all included in the file callback.c in the 70 readline distribution. This file provides (mainly) a function, which 71 the event loop uses as callback (i.e. event handler) whenever an event 72 is detected on the standard input file descriptor. 73 readline_callback_read_char is called (by the GDB event loop) whenever 74 there is a new character ready on the input stream. This function 75 incrementally builds a buffer internal to readline where it 76 accumulates the line read up to the point of invocation. In the 77 special case in which the character read is newline, the function 78 invokes a GDB supplied callback routine, which does the processing of 79 a full command line. This latter routine is the asynchronous analog 80 of the old command_line_input in gdb. Instead of invoking (and waiting 81 for) readline to read the command line and pass it back to 82 command_loop for processing, the new command_line_handler function has 83 the command line already available as its parameter. INPUT_HANDLER is 84 to be set to the function that readline will invoke when a complete 85 line of input is ready. CALL_READLINE is to be set to the function 86 that readline offers as callback to the event_loop. */ 87 88void (*input_handler) (char *); 89void (*call_readline) (gdb_client_data); 90 91/* Important variables for the event loop. */ 92 93/* This is used to determine if GDB is using the readline library or 94 its own simplified form of readline. It is used by the asynchronous 95 form of the set editing command. 96 ezannoni: as of 1999-04-29 I expect that this 97 variable will not be used after gdb is changed to use the event 98 loop as default engine, and event-top.c is merged into top.c. */ 99int async_command_editing_p; 100 101/* This variable contains the new prompt that the user sets with the 102 set prompt command. */ 103char *new_async_prompt; 104 105/* This is the annotation suffix that will be used when the 106 annotation_level is 2. */ 107char *async_annotation_suffix; 108 109/* This is used to display the notification of the completion of an 110 asynchronous execution command. */ 111int exec_done_display_p = 0; 112 113/* This is the file descriptor for the input stream that GDB uses to 114 read commands from. */ 115int input_fd; 116 117/* This is the prompt stack. Prompts will be pushed on the stack as 118 needed by the different 'kinds' of user inputs GDB is asking 119 for. See event-loop.h. */ 120struct prompts the_prompts; 121 122/* signal handling variables */ 123/* Each of these is a pointer to a function that the event loop will 124 invoke if the corresponding signal has received. The real signal 125 handlers mark these functions as ready to be executed and the event 126 loop, in a later iteration, calls them. See the function 127 invoke_async_signal_handler. */ 128void *sigint_token; 129#ifdef SIGHUP 130void *sighup_token; 131#endif 132void *sigquit_token; 133void *sigfpe_token; 134#if defined(SIGWINCH) && defined(SIGWINCH_HANDLER) 135void *sigwinch_token; 136#endif 137#ifdef STOP_SIGNAL 138void *sigtstp_token; 139#endif 140 141/* Structure to save a partially entered command. This is used when 142 the user types '\' at the end of a command line. This is necessary 143 because each line of input is handled by a different call to 144 command_line_handler, and normally there is no state retained 145 between different calls. */ 146int more_to_come = 0; 147 148struct readline_input_state 149 { 150 char *linebuffer; 151 char *linebuffer_ptr; 152 } 153readline_input_state; 154 155/* This hook is called by rl_callback_read_char_wrapper after each 156 character is processed. */ 157void (*after_char_processing_hook) (); 158 159 160/* Wrapper function for calling into the readline library. The event 161 loop expects the callback function to have a paramter, while readline 162 expects none. */ 163static void 164rl_callback_read_char_wrapper (gdb_client_data client_data) 165{ 166 rl_callback_read_char (); 167 if (after_char_processing_hook) 168 (*after_char_processing_hook) (); 169} 170 171/* Initialize all the necessary variables, start the event loop, 172 register readline, and stdin, start the loop. */ 173void 174cli_command_loop (void) 175{ 176 int length; 177 char *a_prompt; 178 char *gdb_prompt = get_prompt (); 179 180 /* If we are using readline, set things up and display the first 181 prompt, otherwise just print the prompt. */ 182 if (async_command_editing_p) 183 { 184 /* Tell readline what the prompt to display is and what function it 185 will need to call after a whole line is read. This also displays 186 the first prompt. */ 187 length = strlen (PREFIX (0)) + strlen (gdb_prompt) + strlen (SUFFIX (0)) + 1; 188 a_prompt = (char *) xmalloc (length); 189 strcpy (a_prompt, PREFIX (0)); 190 strcat (a_prompt, gdb_prompt); 191 strcat (a_prompt, SUFFIX (0)); 192 rl_callback_handler_install (a_prompt, input_handler); 193 } 194 else 195 display_gdb_prompt (0); 196 197 /* Now it's time to start the event loop. */ 198 start_event_loop (); 199} 200 201/* Change the function to be invoked every time there is a character 202 ready on stdin. This is used when the user sets the editing off, 203 therefore bypassing readline, and letting gdb handle the input 204 itself, via gdb_readline2. Also it is used in the opposite case in 205 which the user sets editing on again, by restoring readline 206 handling of the input. */ 207static void 208change_line_handler (void) 209{ 210 /* NOTE: this operates on input_fd, not instream. If we are reading 211 commands from a file, instream will point to the file. However in 212 async mode, we always read commands from a file with editing 213 off. This means that the 'set editing on/off' will have effect 214 only on the interactive session. */ 215 216 if (async_command_editing_p) 217 { 218 /* Turn on editing by using readline. */ 219 call_readline = rl_callback_read_char_wrapper; 220 input_handler = command_line_handler; 221 } 222 else 223 { 224 /* Turn off editing by using gdb_readline2. */ 225 rl_callback_handler_remove (); 226 call_readline = gdb_readline2; 227 228 /* Set up the command handler as well, in case we are called as 229 first thing from .gdbinit. */ 230 input_handler = command_line_handler; 231 } 232} 233 234/* Displays the prompt. The prompt that is displayed is the current 235 top of the prompt stack, if the argument NEW_PROMPT is 236 0. Otherwise, it displays whatever NEW_PROMPT is. This is used 237 after each gdb command has completed, and in the following cases: 238 1. when the user enters a command line which is ended by '\' 239 indicating that the command will continue on the next line. 240 In that case the prompt that is displayed is the empty string. 241 2. When the user is entering 'commands' for a breakpoint, or 242 actions for a tracepoint. In this case the prompt will be '>' 243 3. Other???? 244 FIXME: 2. & 3. not implemented yet for async. */ 245void 246display_gdb_prompt (char *new_prompt) 247{ 248 int prompt_length = 0; 249 char *gdb_prompt = get_prompt (); 250 251 /* Each interpreter has its own rules on displaying the command 252 prompt. */ 253 if (!current_interp_display_prompt_p ()) 254 return; 255 256 if (target_executing && sync_execution) 257 { 258 /* This is to trick readline into not trying to display the 259 prompt. Even though we display the prompt using this 260 function, readline still tries to do its own display if we 261 don't call rl_callback_handler_install and 262 rl_callback_handler_remove (which readline detects because a 263 global variable is not set). If readline did that, it could 264 mess up gdb signal handlers for SIGINT. Readline assumes 265 that between calls to rl_set_signals and rl_clear_signals gdb 266 doesn't do anything with the signal handlers. Well, that's 267 not the case, because when the target executes we change the 268 SIGINT signal handler. If we allowed readline to display the 269 prompt, the signal handler change would happen exactly 270 between the calls to the above two functions. 271 Calling rl_callback_handler_remove(), does the job. */ 272 273 rl_callback_handler_remove (); 274 return; 275 } 276 277 if (!new_prompt) 278 { 279 /* Just use the top of the prompt stack. */ 280 prompt_length = strlen (PREFIX (0)) + 281 strlen (SUFFIX (0)) + 282 strlen (gdb_prompt) + 1; 283 284 new_prompt = (char *) alloca (prompt_length); 285 286 /* Prefix needs to have new line at end. */ 287 strcpy (new_prompt, PREFIX (0)); 288 strcat (new_prompt, gdb_prompt); 289 /* Suffix needs to have a new line at end and \032 \032 at 290 beginning. */ 291 strcat (new_prompt, SUFFIX (0)); 292 } 293 294 if (async_command_editing_p) 295 { 296 rl_callback_handler_remove (); 297 rl_callback_handler_install (new_prompt, input_handler); 298 } 299 /* new_prompt at this point can be the top of the stack or the one passed in */ 300 else if (new_prompt) 301 { 302 /* Don't use a _filtered function here. It causes the assumed 303 character position to be off, since the newline we read from 304 the user is not accounted for. */ 305 fputs_unfiltered (new_prompt, gdb_stdout); 306 gdb_flush (gdb_stdout); 307 } 308} 309 310/* Used when the user requests a different annotation level, with 311 'set annotate'. It pushes a new prompt (with prefix and suffix) on top 312 of the prompt stack, if the annotation level desired is 2, otherwise 313 it pops the top of the prompt stack when we want the annotation level 314 to be the normal ones (1 or 0). */ 315static void 316change_annotation_level (void) 317{ 318 char *prefix, *suffix; 319 320 if (!PREFIX (0) || !PROMPT (0) || !SUFFIX (0)) 321 { 322 /* The prompt stack has not been initialized to "", we are 323 using gdb w/o the --async switch */ 324 warning ("Command has same effect as set annotate"); 325 return; 326 } 327 328 if (annotation_level > 1) 329 { 330 if (!strcmp (PREFIX (0), "") && !strcmp (SUFFIX (0), "")) 331 { 332 /* Push a new prompt if the previous annotation_level was not >1. */ 333 prefix = (char *) alloca (strlen (async_annotation_suffix) + 10); 334 strcpy (prefix, "\n\032\032pre-"); 335 strcat (prefix, async_annotation_suffix); 336 strcat (prefix, "\n"); 337 338 suffix = (char *) alloca (strlen (async_annotation_suffix) + 6); 339 strcpy (suffix, "\n\032\032"); 340 strcat (suffix, async_annotation_suffix); 341 strcat (suffix, "\n"); 342 343 push_prompt (prefix, (char *) 0, suffix); 344 } 345 } 346 else 347 { 348 if (strcmp (PREFIX (0), "") && strcmp (SUFFIX (0), "")) 349 { 350 /* Pop the top of the stack, we are going back to annotation < 1. */ 351 pop_prompt (); 352 } 353 } 354} 355 356/* Pushes a new prompt on the prompt stack. Each prompt has three 357 parts: prefix, prompt, suffix. Usually prefix and suffix are empty 358 strings, except when the annotation level is 2. Memory is allocated 359 within savestring for the new prompt. */ 360void 361push_prompt (char *prefix, char *prompt, char *suffix) 362{ 363 the_prompts.top++; 364 PREFIX (0) = savestring (prefix, strlen (prefix)); 365 366 /* Note that this function is used by the set annotate 2 367 command. This is why we take care of saving the old prompt 368 in case a new one is not specified. */ 369 if (prompt) 370 PROMPT (0) = savestring (prompt, strlen (prompt)); 371 else 372 PROMPT (0) = savestring (PROMPT (-1), strlen (PROMPT (-1))); 373 374 SUFFIX (0) = savestring (suffix, strlen (suffix)); 375} 376 377/* Pops the top of the prompt stack, and frees the memory allocated for it. */ 378void 379pop_prompt (void) 380{ 381 /* If we are not during a 'synchronous' execution command, in which 382 case, the top prompt would be empty. */ 383 if (strcmp (PROMPT (0), "")) 384 /* This is for the case in which the prompt is set while the 385 annotation level is 2. The top prompt will be changed, but when 386 we return to annotation level < 2, we want that new prompt to be 387 in effect, until the user does another 'set prompt'. */ 388 if (strcmp (PROMPT (0), PROMPT (-1))) 389 { 390 xfree (PROMPT (-1)); 391 PROMPT (-1) = savestring (PROMPT (0), strlen (PROMPT (0))); 392 } 393 394 xfree (PREFIX (0)); 395 xfree (PROMPT (0)); 396 xfree (SUFFIX (0)); 397 the_prompts.top--; 398} 399 400/* When there is an event ready on the stdin file desriptor, instead 401 of calling readline directly throught the callback function, or 402 instead of calling gdb_readline2, give gdb a chance to detect 403 errors and do something. */ 404void 405stdin_event_handler (int error, gdb_client_data client_data) 406{ 407 if (error) 408 { 409 printf_unfiltered ("error detected on stdin\n"); 410 delete_file_handler (input_fd); 411 discard_all_continuations (); 412 /* If stdin died, we may as well kill gdb. */ 413 quit_command ((char *) 0, stdin == instream); 414 } 415 else 416 (*call_readline) (client_data); 417} 418 419/* Re-enable stdin after the end of an execution command in 420 synchronous mode, or after an error from the target, and we aborted 421 the exec operation. */ 422 423void 424async_enable_stdin (void *dummy) 425{ 426 /* See NOTE in async_disable_stdin() */ 427 /* FIXME: cagney/1999-09-27: Call this before clearing 428 sync_execution. Current target_terminal_ours() implementations 429 check for sync_execution before switching the terminal. */ 430 target_terminal_ours (); 431 pop_prompt (); 432 sync_execution = 0; 433} 434 435/* Disable reads from stdin (the console) marking the command as 436 synchronous. */ 437 438void 439async_disable_stdin (void) 440{ 441 sync_execution = 1; 442 push_prompt ("", "", ""); 443 /* FIXME: cagney/1999-09-27: At present this call is technically 444 redundant since infcmd.c and infrun.c both already call 445 target_terminal_inferior(). As the terminal handling (in 446 sync/async mode) is refined, the duplicate calls can be 447 eliminated (Here or in infcmd.c/infrun.c). */ 448 target_terminal_inferior (); 449 /* Add the reinstate of stdin to the list of cleanups to be done 450 in case the target errors out and dies. These cleanups are also 451 done in case of normal successful termination of the execution 452 command, by complete_execution(). */ 453 make_exec_error_cleanup (async_enable_stdin, NULL); 454} 455 456 457/* Handles a gdb command. This function is called by 458 command_line_handler, which has processed one or more input lines 459 into COMMAND. */ 460/* NOTE: 1999-04-30 This is the asynchronous version of the command_loop 461 function. The command_loop function will be obsolete when we 462 switch to use the event loop at every execution of gdb. */ 463static void 464command_handler (char *command) 465{ 466 struct cleanup *old_chain; 467 int stdin_is_tty = ISATTY (stdin); 468 struct continuation_arg *arg1; 469 struct continuation_arg *arg2; 470 long time_at_cmd_start; 471#ifdef HAVE_SBRK 472 long space_at_cmd_start = 0; 473#endif 474 extern int display_time; 475 extern int display_space; 476 477 quit_flag = 0; 478 if (instream == stdin && stdin_is_tty) 479 reinitialize_more_filter (); 480 old_chain = make_cleanup (null_cleanup, 0); 481 482 /* If readline returned a NULL command, it means that the 483 connection with the terminal is gone. This happens at the 484 end of a testsuite run, after Expect has hung up 485 but GDB is still alive. In such a case, we just quit gdb 486 killing the inferior program too. */ 487 if (command == 0) 488 quit_command ((char *) 0, stdin == instream); 489 490 time_at_cmd_start = get_run_time (); 491 492 if (display_space) 493 { 494#ifdef HAVE_SBRK 495 char *lim = (char *) sbrk (0); 496 space_at_cmd_start = lim - lim_at_start; 497#endif 498 } 499 500 execute_command (command, instream == stdin); 501 502 /* Set things up for this function to be compete later, once the 503 execution has completed, if we are doing an execution command, 504 otherwise, just go ahead and finish. */ 505 if (target_can_async_p () && target_executing) 506 { 507 arg1 = 508 (struct continuation_arg *) xmalloc (sizeof (struct continuation_arg)); 509 arg2 = 510 (struct continuation_arg *) xmalloc (sizeof (struct continuation_arg)); 511 arg1->next = arg2; 512 arg2->next = NULL; 513 arg1->data.longint = time_at_cmd_start; 514#ifdef HAVE_SBRK 515 arg2->data.longint = space_at_cmd_start; 516#endif 517 add_continuation (command_line_handler_continuation, arg1); 518 } 519 520 /* Do any commands attached to breakpoint we stopped at. Only if we 521 are always running synchronously. Or if we have just executed a 522 command that doesn't start the target. */ 523 if (!target_can_async_p () || !target_executing) 524 { 525 bpstat_do_actions (&stop_bpstat); 526 do_cleanups (old_chain); 527 528 if (display_time) 529 { 530 long cmd_time = get_run_time () - time_at_cmd_start; 531 532 printf_unfiltered ("Command execution time: %ld.%06ld\n", 533 cmd_time / 1000000, cmd_time % 1000000); 534 } 535 536 if (display_space) 537 { 538#ifdef HAVE_SBRK 539 char *lim = (char *) sbrk (0); 540 long space_now = lim - lim_at_start; 541 long space_diff = space_now - space_at_cmd_start; 542 543 printf_unfiltered ("Space used: %ld (%c%ld for this command)\n", 544 space_now, 545 (space_diff >= 0 ? '+' : '-'), 546 space_diff); 547#endif 548 } 549 } 550} 551 552/* Do any commands attached to breakpoint we stopped at. Only if we 553 are always running synchronously. Or if we have just executed a 554 command that doesn't start the target. */ 555void 556command_line_handler_continuation (struct continuation_arg *arg) 557{ 558 extern int display_time; 559 extern int display_space; 560 561 long time_at_cmd_start = arg->data.longint; 562 long space_at_cmd_start = arg->next->data.longint; 563 564 bpstat_do_actions (&stop_bpstat); 565 /*do_cleanups (old_chain); *//*?????FIXME????? */ 566 567 if (display_time) 568 { 569 long cmd_time = get_run_time () - time_at_cmd_start; 570 571 printf_unfiltered ("Command execution time: %ld.%06ld\n", 572 cmd_time / 1000000, cmd_time % 1000000); 573 } 574 if (display_space) 575 { 576#ifdef HAVE_SBRK 577 char *lim = (char *) sbrk (0); 578 long space_now = lim - lim_at_start; 579 long space_diff = space_now - space_at_cmd_start; 580 581 printf_unfiltered ("Space used: %ld (%c%ld for this command)\n", 582 space_now, 583 (space_diff >= 0 ? '+' : '-'), 584 space_diff); 585#endif 586 } 587} 588 589/* Handle a complete line of input. This is called by the callback 590 mechanism within the readline library. Deal with incomplete commands 591 as well, by saving the partial input in a global buffer. */ 592 593/* NOTE: 1999-04-30 This is the asynchronous version of the 594 command_line_input function. command_line_input will become 595 obsolete once we use the event loop as the default mechanism in 596 GDB. */ 597static void 598command_line_handler (char *rl) 599{ 600 static char *linebuffer = 0; 601 static unsigned linelength = 0; 602 char *p; 603 char *p1; 604 extern char *line; 605 extern int linesize; 606 char *nline; 607 char got_eof = 0; 608 609 610 int repeat = (instream == stdin); 611 612 if (annotation_level > 1 && instream == stdin) 613 { 614 printf_unfiltered ("\n\032\032post-"); 615 puts_unfiltered (async_annotation_suffix); 616 printf_unfiltered ("\n"); 617 } 618 619 if (linebuffer == 0) 620 { 621 linelength = 80; 622 linebuffer = (char *) xmalloc (linelength); 623 } 624 625 p = linebuffer; 626 627 if (more_to_come) 628 { 629 strcpy (linebuffer, readline_input_state.linebuffer); 630 p = readline_input_state.linebuffer_ptr; 631 xfree (readline_input_state.linebuffer); 632 more_to_come = 0; 633 pop_prompt (); 634 } 635 636#ifdef STOP_SIGNAL 637 if (job_control) 638 signal (STOP_SIGNAL, handle_stop_sig); 639#endif 640 641 /* Make sure that all output has been output. Some machines may let 642 you get away with leaving out some of the gdb_flush, but not all. */ 643 wrap_here (""); 644 gdb_flush (gdb_stdout); 645 gdb_flush (gdb_stderr); 646 647 if (source_file_name != NULL) 648 { 649 ++source_line_number; 650 sprintf (source_error, 651 "%s%s:%d: Error in sourced command file:\n", 652 source_pre_error, 653 source_file_name, 654 source_line_number); 655 error_pre_print = source_error; 656 } 657 658 /* If we are in this case, then command_handler will call quit 659 and exit from gdb. */ 660 if (!rl || rl == (char *) EOF) 661 { 662 got_eof = 1; 663 command_handler (0); 664 } 665 if (strlen (rl) + 1 + (p - linebuffer) > linelength) 666 { 667 linelength = strlen (rl) + 1 + (p - linebuffer); 668 nline = (char *) xrealloc (linebuffer, linelength); 669 p += nline - linebuffer; 670 linebuffer = nline; 671 } 672 p1 = rl; 673 /* Copy line. Don't copy null at end. (Leaves line alone 674 if this was just a newline) */ 675 while (*p1) 676 *p++ = *p1++; 677 678 xfree (rl); /* Allocated in readline. */ 679 680 if (p > linebuffer && *(p - 1) == '\\') 681 { 682 p--; /* Put on top of '\'. */ 683 684 readline_input_state.linebuffer = savestring (linebuffer, 685 strlen (linebuffer)); 686 readline_input_state.linebuffer_ptr = p; 687 688 /* We will not invoke a execute_command if there is more 689 input expected to complete the command. So, we need to 690 print an empty prompt here. */ 691 more_to_come = 1; 692 push_prompt ("", "", ""); 693 display_gdb_prompt (0); 694 return; 695 } 696 697#ifdef STOP_SIGNAL 698 if (job_control) 699 signal (STOP_SIGNAL, SIG_DFL); 700#endif 701 702#define SERVER_COMMAND_LENGTH 7 703 server_command = 704 (p - linebuffer > SERVER_COMMAND_LENGTH) 705 && strncmp (linebuffer, "server ", SERVER_COMMAND_LENGTH) == 0; 706 if (server_command) 707 { 708 /* Note that we don't set `line'. Between this and the check in 709 dont_repeat, this insures that repeating will still do the 710 right thing. */ 711 *p = '\0'; 712 command_handler (linebuffer + SERVER_COMMAND_LENGTH); 713 display_gdb_prompt (0); 714 return; 715 } 716 717 /* Do history expansion if that is wished. */ 718 if (history_expansion_p && instream == stdin 719 && ISATTY (instream)) 720 { 721 char *history_value; 722 int expanded; 723 724 *p = '\0'; /* Insert null now. */ 725 expanded = history_expand (linebuffer, &history_value); 726 if (expanded) 727 { 728 /* Print the changes. */ 729 printf_unfiltered ("%s\n", history_value); 730 731 /* If there was an error, call this function again. */ 732 if (expanded < 0) 733 { 734 xfree (history_value); 735 return; 736 } 737 if (strlen (history_value) > linelength) 738 { 739 linelength = strlen (history_value) + 1; 740 linebuffer = (char *) xrealloc (linebuffer, linelength); 741 } 742 strcpy (linebuffer, history_value); 743 p = linebuffer + strlen (linebuffer); 744 xfree (history_value); 745 } 746 } 747 748 /* If we just got an empty line, and that is supposed 749 to repeat the previous command, return the value in the 750 global buffer. */ 751 if (repeat && p == linebuffer && *p != '\\') 752 { 753 command_handler (line); 754 display_gdb_prompt (0); 755 return; 756 } 757 758 for (p1 = linebuffer; *p1 == ' ' || *p1 == '\t'; p1++); 759 if (repeat && !*p1) 760 { 761 command_handler (line); 762 display_gdb_prompt (0); 763 return; 764 } 765 766 *p = 0; 767 768 /* Add line to history if appropriate. */ 769 if (instream == stdin 770 && ISATTY (stdin) && *linebuffer) 771 add_history (linebuffer); 772 773 /* Note: lines consisting solely of comments are added to the command 774 history. This is useful when you type a command, and then 775 realize you don't want to execute it quite yet. You can comment 776 out the command and then later fetch it from the value history 777 and remove the '#'. The kill ring is probably better, but some 778 people are in the habit of commenting things out. */ 779 if (*p1 == '#') 780 *p1 = '\0'; /* Found a comment. */ 781 782 /* Save into global buffer if appropriate. */ 783 if (repeat) 784 { 785 if (linelength > linesize) 786 { 787 line = xrealloc (line, linelength); 788 linesize = linelength; 789 } 790 strcpy (line, linebuffer); 791 if (!more_to_come) 792 { 793 command_handler (line); 794 display_gdb_prompt (0); 795 } 796 return; 797 } 798 799 command_handler (linebuffer); 800 display_gdb_prompt (0); 801 return; 802} 803 804/* Does reading of input from terminal w/o the editing features 805 provided by the readline library. */ 806 807/* NOTE: 1999-04-30 Asynchronous version of gdb_readline. gdb_readline 808 will become obsolete when the event loop is made the default 809 execution for gdb. */ 810void 811gdb_readline2 (gdb_client_data client_data) 812{ 813 int c; 814 char *result; 815 int input_index = 0; 816 int result_size = 80; 817 static int done_once = 0; 818 819 /* Unbuffer the input stream, so that, later on, the calls to fgetc 820 fetch only one char at the time from the stream. The fgetc's will 821 get up to the first newline, but there may be more chars in the 822 stream after '\n'. If we buffer the input and fgetc drains the 823 stream, getting stuff beyond the newline as well, a select, done 824 afterwards will not trigger. */ 825 if (!done_once && !ISATTY (instream)) 826 { 827 setbuf (instream, NULL); 828 done_once = 1; 829 } 830 831 result = (char *) xmalloc (result_size); 832 833 /* We still need the while loop here, even though it would seem 834 obvious to invoke gdb_readline2 at every character entered. If 835 not using the readline library, the terminal is in cooked mode, 836 which sends the characters all at once. Poll will notice that the 837 input fd has changed state only after enter is pressed. At this 838 point we still need to fetch all the chars entered. */ 839 840 while (1) 841 { 842 /* Read from stdin if we are executing a user defined command. 843 This is the right thing for prompt_for_continue, at least. */ 844 c = fgetc (instream ? instream : stdin); 845 846 if (c == EOF) 847 { 848 if (input_index > 0) 849 /* The last line does not end with a newline. Return it, and 850 if we are called again fgetc will still return EOF and 851 we'll return NULL then. */ 852 break; 853 xfree (result); 854 (*input_handler) (0); 855 } 856 857 if (c == '\n') 858#ifndef CRLF_SOURCE_FILES 859 break; 860#else 861 { 862 if (input_index > 0 && result[input_index - 1] == '\r') 863 input_index--; 864 break; 865 } 866#endif 867 868 result[input_index++] = c; 869 while (input_index >= result_size) 870 { 871 result_size *= 2; 872 result = (char *) xrealloc (result, result_size); 873 } 874 } 875 876 result[input_index++] = '\0'; 877 (*input_handler) (result); 878} 879 880 881/* Initialization of signal handlers and tokens. There is a function 882 handle_sig* for each of the signals GDB cares about. Specifically: 883 SIGINT, SIGFPE, SIGQUIT, SIGTSTP, SIGHUP, SIGWINCH. These 884 functions are the actual signal handlers associated to the signals 885 via calls to signal(). The only job for these functions is to 886 enqueue the appropriate event/procedure with the event loop. Such 887 procedures are the old signal handlers. The event loop will take 888 care of invoking the queued procedures to perform the usual tasks 889 associated with the reception of the signal. */ 890/* NOTE: 1999-04-30 This is the asynchronous version of init_signals. 891 init_signals will become obsolete as we move to have to event loop 892 as the default for gdb. */ 893void 894async_init_signals (void) 895{ 896 signal (SIGINT, handle_sigint); 897 sigint_token = 898 create_async_signal_handler (async_request_quit, NULL); 899 900 /* If SIGTRAP was set to SIG_IGN, then the SIG_IGN will get passed 901 to the inferior and breakpoints will be ignored. */ 902#ifdef SIGTRAP 903 signal (SIGTRAP, SIG_DFL); 904#endif 905 906 /* If we initialize SIGQUIT to SIG_IGN, then the SIG_IGN will get 907 passed to the inferior, which we don't want. It would be 908 possible to do a "signal (SIGQUIT, SIG_DFL)" after we fork, but 909 on BSD4.3 systems using vfork, that can affect the 910 GDB process as well as the inferior (the signal handling tables 911 might be in memory, shared between the two). Since we establish 912 a handler for SIGQUIT, when we call exec it will set the signal 913 to SIG_DFL for us. */ 914 signal (SIGQUIT, handle_sigquit); 915 sigquit_token = 916 create_async_signal_handler (async_do_nothing, NULL); 917#ifdef SIGHUP 918 if (signal (SIGHUP, handle_sighup) != SIG_IGN) 919 sighup_token = 920 create_async_signal_handler (async_disconnect, NULL); 921 else 922 sighup_token = 923 create_async_signal_handler (async_do_nothing, NULL); 924#endif 925 signal (SIGFPE, handle_sigfpe); 926 sigfpe_token = 927 create_async_signal_handler (async_float_handler, NULL); 928 929#if defined(SIGWINCH) && defined(SIGWINCH_HANDLER) 930 signal (SIGWINCH, handle_sigwinch); 931 sigwinch_token = 932 create_async_signal_handler (SIGWINCH_HANDLER, NULL); 933#endif 934#ifdef STOP_SIGNAL 935 sigtstp_token = 936 create_async_signal_handler (async_stop_sig, NULL); 937#endif 938 939} 940 941void 942mark_async_signal_handler_wrapper (void *token) 943{ 944 mark_async_signal_handler ((struct async_signal_handler *) token); 945} 946 947/* Tell the event loop what to do if SIGINT is received. 948 See event-signal.c. */ 949void 950handle_sigint (int sig) 951{ 952 signal (sig, handle_sigint); 953 954 /* If immediate_quit is set, we go ahead and process the SIGINT right 955 away, even if we usually would defer this to the event loop. The 956 assumption here is that it is safe to process ^C immediately if 957 immediate_quit is set. If we didn't, SIGINT would be really 958 processed only the next time through the event loop. To get to 959 that point, though, the command that we want to interrupt needs to 960 finish first, which is unacceptable. */ 961 if (immediate_quit) 962 async_request_quit (0); 963 else 964 /* If immediate quit is not set, we process SIGINT the next time 965 through the loop, which is fine. */ 966 mark_async_signal_handler_wrapper (sigint_token); 967} 968 969/* Do the quit. All the checks have been done by the caller. */ 970void 971async_request_quit (gdb_client_data arg) 972{ 973 quit_flag = 1; 974 quit (); 975} 976 977/* Tell the event loop what to do if SIGQUIT is received. 978 See event-signal.c. */ 979static void 980handle_sigquit (int sig) 981{ 982 mark_async_signal_handler_wrapper (sigquit_token); 983 signal (sig, handle_sigquit); 984} 985 986/* Called by the event loop in response to a SIGQUIT. */ 987static void 988async_do_nothing (gdb_client_data arg) 989{ 990 /* Empty function body. */ 991} 992 993#ifdef SIGHUP 994/* Tell the event loop what to do if SIGHUP is received. 995 See event-signal.c. */ 996static void 997handle_sighup (int sig) 998{ 999 mark_async_signal_handler_wrapper (sighup_token); 1000 signal (sig, handle_sighup); 1001} 1002 1003/* Called by the event loop to process a SIGHUP */ 1004static void 1005async_disconnect (gdb_client_data arg) 1006{ 1007 catch_errors (quit_cover, NULL, 1008 "Could not kill the program being debugged", 1009 RETURN_MASK_ALL); 1010 signal (SIGHUP, SIG_DFL); /*FIXME: ??????????? */ 1011 kill (getpid (), SIGHUP); 1012} 1013#endif 1014 1015#ifdef STOP_SIGNAL 1016void 1017handle_stop_sig (int sig) 1018{ 1019 mark_async_signal_handler_wrapper (sigtstp_token); 1020 signal (sig, handle_stop_sig); 1021} 1022 1023static void 1024async_stop_sig (gdb_client_data arg) 1025{ 1026 char *prompt = get_prompt (); 1027#if STOP_SIGNAL == SIGTSTP 1028 signal (SIGTSTP, SIG_DFL); 1029#if HAVE_SIGPROCMASK 1030 { 1031 sigset_t zero; 1032 1033 sigemptyset (&zero); 1034 sigprocmask (SIG_SETMASK, &zero, 0); 1035 } 1036#elif HAVE_SIGSETMASK 1037 sigsetmask (0); 1038#endif 1039 kill (getpid (), SIGTSTP); 1040 signal (SIGTSTP, handle_stop_sig); 1041#else 1042 signal (STOP_SIGNAL, handle_stop_sig); 1043#endif 1044 printf_unfiltered ("%s", prompt); 1045 gdb_flush (gdb_stdout); 1046 1047 /* Forget about any previous command -- null line now will do nothing. */ 1048 dont_repeat (); 1049} 1050#endif /* STOP_SIGNAL */ 1051 1052/* Tell the event loop what to do if SIGFPE is received. 1053 See event-signal.c. */ 1054static void 1055handle_sigfpe (int sig) 1056{ 1057 mark_async_signal_handler_wrapper (sigfpe_token); 1058 signal (sig, handle_sigfpe); 1059} 1060 1061/* Event loop will call this functin to process a SIGFPE. */ 1062static void 1063async_float_handler (gdb_client_data arg) 1064{ 1065 /* This message is based on ANSI C, section 4.7. Note that integer 1066 divide by zero causes this, so "float" is a misnomer. */ 1067 error ("Erroneous arithmetic operation."); 1068} 1069 1070/* Tell the event loop what to do if SIGWINCH is received. 1071 See event-signal.c. */ 1072#if defined(SIGWINCH) && defined(SIGWINCH_HANDLER) 1073static void 1074handle_sigwinch (int sig) 1075{ 1076 mark_async_signal_handler_wrapper (sigwinch_token); 1077 signal (sig, handle_sigwinch); 1078} 1079#endif 1080 1081 1082/* Called by do_setshow_command. */ 1083void 1084set_async_editing_command (char *args, int from_tty, struct cmd_list_element *c) 1085{ 1086 change_line_handler (); 1087} 1088 1089/* Called by do_setshow_command. */ 1090void 1091set_async_annotation_level (char *args, int from_tty, struct cmd_list_element *c) 1092{ 1093 change_annotation_level (); 1094} 1095 1096/* Called by do_setshow_command. */ 1097void 1098set_async_prompt (char *args, int from_tty, struct cmd_list_element *c) 1099{ 1100 PROMPT (0) = savestring (new_async_prompt, strlen (new_async_prompt)); 1101} 1102 1103/* Set things up for readline to be invoked via the alternate 1104 interface, i.e. via a callback function (rl_callback_read_char), 1105 and hook up instream to the event loop. */ 1106void 1107gdb_setup_readline (void) 1108{ 1109 /* This function is a noop for the sync case. The assumption is that 1110 the sync setup is ALL done in gdb_init, and we would only mess it up 1111 here. The sync stuff should really go away over time. */ 1112 1113 if (event_loop_p) 1114 { 1115 gdb_stdout = stdio_fileopen (stdout); 1116 gdb_stderr = stdio_fileopen (stderr); 1117 gdb_stdlog = gdb_stderr; /* for moment */ 1118 gdb_stdtarg = gdb_stderr; /* for moment */ 1119 1120 /* If the input stream is connected to a terminal, turn on 1121 editing. */ 1122 if (ISATTY (instream)) 1123 { 1124 /* Tell gdb that we will be using the readline library. This 1125 could be overwritten by a command in .gdbinit like 'set 1126 editing on' or 'off'. */ 1127 async_command_editing_p = 1; 1128 1129 /* When a character is detected on instream by select or 1130 poll, readline will be invoked via this callback 1131 function. */ 1132 call_readline = rl_callback_read_char_wrapper; 1133 } 1134 else 1135 { 1136 async_command_editing_p = 0; 1137 call_readline = gdb_readline2; 1138 } 1139 1140 /* When readline has read an end-of-line character, it passes 1141 the complete line to gdb for processing. command_line_handler 1142 is the function that does this. */ 1143 input_handler = command_line_handler; 1144 1145 /* Tell readline to use the same input stream that gdb uses. */ 1146 rl_instream = instream; 1147 1148 /* Get a file descriptor for the input stream, so that we can 1149 register it with the event loop. */ 1150 input_fd = fileno (instream); 1151 1152 /* Now we need to create the event sources for the input file 1153 descriptor. */ 1154 /* At this point in time, this is the only event source that we 1155 register with the even loop. Another source is going to be 1156 the target program (inferior), but that must be registered 1157 only when it actually exists (I.e. after we say 'run' or 1158 after we connect to a remote target. */ 1159 add_file_handler (input_fd, stdin_event_handler, 0); 1160 } 1161} 1162 1163/* Disable command input through the standard CLI channels. Used in 1164 the suspend proc for interpreters that use the standard gdb readline 1165 interface, like the cli & the mi. */ 1166void 1167gdb_disable_readline (void) 1168{ 1169 if (event_loop_p) 1170 { 1171 /* FIXME - It is too heavyweight to delete and remake these 1172 every time you run an interpreter that needs readline. 1173 It is probably better to have the interpreters cache these, 1174 which in turn means that this needs to be moved into interpreter 1175 specific code. */ 1176 1177#if 0 1178 ui_file_delete (gdb_stdout); 1179 ui_file_delete (gdb_stderr); 1180 gdb_stdlog = NULL; 1181 gdb_stdtarg = NULL; 1182#endif 1183 1184 rl_callback_handler_remove (); 1185 delete_file_handler (input_fd); 1186 } 1187} 1188