1 /* Handling of inferior events for the event loop for GDB, the GNU debugger. 2 Copyright (C) 1999, 2007-2012 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 3 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, see <http://www.gnu.org/licenses/>. */ 19 20 #include "defs.h" 21 #include "inferior.h" /* For fetch_inferior_event. */ 22 #include "target.h" /* For enum inferior_event_type. */ 23 #include "event-loop.h" 24 #include "event-top.h" 25 #include "inf-loop.h" 26 #include "remote.h" 27 #include "exceptions.h" 28 #include "language.h" 29 #include "gdbthread.h" 30 #include "continuations.h" 31 #include "interps.h" 32 33 static int fetch_inferior_event_wrapper (gdb_client_data client_data); 34 35 /* General function to handle events in the inferior. So far it just 36 takes care of detecting errors reported by select() or poll(), 37 otherwise it assumes that all is OK, and goes on reading data from 38 the fd. This however may not always be what we want to do. */ 39 void 40 inferior_event_handler (enum inferior_event_type event_type, 41 gdb_client_data client_data) 42 { 43 struct cleanup *cleanup_if_error = make_bpstat_clear_actions_cleanup (); 44 45 switch (event_type) 46 { 47 case INF_REG_EVENT: 48 /* Use catch errors for now, until the inner layers of 49 fetch_inferior_event (i.e. readchar) can return meaningful 50 error status. If an error occurs while getting an event from 51 the target, just cancel the current command. */ 52 if (!catch_errors (fetch_inferior_event_wrapper, 53 client_data, "", RETURN_MASK_ALL)) 54 { 55 bpstat_clear_actions (); 56 do_all_intermediate_continuations (1); 57 do_all_continuations (1); 58 async_enable_stdin (); 59 display_gdb_prompt (0); 60 } 61 break; 62 63 case INF_EXEC_COMPLETE: 64 if (!non_stop) 65 { 66 /* Unregister the inferior from the event loop. This is done 67 so that when the inferior is not running we don't get 68 distracted by spurious inferior output. */ 69 if (target_has_execution) 70 target_async (NULL, 0); 71 } 72 73 /* Do all continuations associated with the whole inferior (not 74 a particular thread). */ 75 if (!ptid_equal (inferior_ptid, null_ptid)) 76 do_all_inferior_continuations (0); 77 78 /* If we were doing a multi-step (eg: step n, next n), but it 79 got interrupted by a breakpoint, still do the pending 80 continuations. The continuation itself is responsible for 81 distinguishing the cases. The continuations are allowed to 82 touch the inferior memory, e.g. to remove breakpoints, so run 83 them before running breakpoint commands, which may resume the 84 target. */ 85 if (non_stop 86 && target_has_execution 87 && !ptid_equal (inferior_ptid, null_ptid)) 88 do_all_intermediate_continuations_thread (inferior_thread (), 0); 89 else 90 do_all_intermediate_continuations (0); 91 92 /* Always finish the previous command before running any 93 breakpoint commands. Any stop cancels the previous command. 94 E.g. a "finish" or "step-n" command interrupted by an 95 unrelated breakpoint is canceled. */ 96 if (non_stop 97 && target_has_execution 98 && !ptid_equal (inferior_ptid, null_ptid)) 99 do_all_continuations_thread (inferior_thread (), 0); 100 else 101 do_all_continuations (0); 102 103 /* When running a command list (from a user command, say), these 104 are only run when the command list is all done. */ 105 if (interpreter_async) 106 { 107 volatile struct gdb_exception e; 108 109 if (info_verbose 110 && current_language != expected_language 111 && language_mode == language_mode_auto) 112 language_info (1); /* Print what changed. */ 113 114 /* Don't propagate breakpoint commands errors. Either we're 115 stopping or some command resumes the inferior. The user will 116 be informed. */ 117 TRY_CATCH (e, RETURN_MASK_ALL) 118 { 119 bpstat_do_actions (); 120 } 121 exception_print (gdb_stderr, e); 122 } 123 break; 124 125 case INF_EXEC_CONTINUE: 126 /* Is there anything left to do for the command issued to 127 complete? */ 128 129 if (non_stop) 130 do_all_intermediate_continuations_thread (inferior_thread (), 0); 131 else 132 do_all_intermediate_continuations (0); 133 break; 134 135 case INF_TIMER: 136 default: 137 printf_unfiltered (_("Event type not recognized.\n")); 138 break; 139 } 140 141 discard_cleanups (cleanup_if_error); 142 } 143 144 static int 145 fetch_inferior_event_wrapper (gdb_client_data client_data) 146 { 147 fetch_inferior_event (client_data); 148 return 1; 149 } 150