x86: also test alternative VMGEXIT encoding

[deliverable/binutils-gdb.git] / gdb / main.c

diff --git a/gdb/main.c b/gdb/main.c
index a0512549da583c36290df0e1e548765b992731fc..3649e4a22018667380237c63fedf425dfe26f531 100644 (file)
--- a/gdb/main.c
+++ b/gdb/main.c
@@ -1,6 +1,6 @@
 /* Top level stuff for GDB, the GNU debugger.
 
-   Copyright (C) 1986-2019 Free Software Foundation, Inc.
+   Copyright (C) 1986-2020 Free Software Foundation, Inc.
 
    This file is part of GDB.
 
@@ -28,7 +28,7 @@
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <ctype.h>
-#include "event-loop.h"
+#include "gdbsupport/event-loop.h"
 #include "ui-out.h"
 
 #include "interps.h"
@@ -52,6 +52,8 @@
 #ifdef GDBTK
 #include "gdbtk/generic/gdbtk.h"
 #endif
+#include "gdbsupport/alt-stack.h"
+#include "observable.h"
 
 /* The selected interpreter.  This will be used as a set command
    variable, so it should always be malloc'ed - since
@@ -123,7 +125,8 @@ set_gdb_data_directory (const char *new_datadir)
       print_sys_errmsg (new_datadir, save_errno);
     }
   else if (!S_ISDIR (st.st_mode))
-    warning (_("%s is not a directory."), new_datadir);
+    warning (_("%ps is not a directory."),
+            styled_string (file_name_style.style (), new_datadir));
 
   gdb_datadir = gdb_realpath (new_datadir).get ();
 
@@ -334,27 +337,59 @@ get_init_files (std::vector<std::string> *system_gdbinit,
   *local_gdbinit = localinit;
 }
 
-/* Try to set up an alternate signal stack for SIGSEGV handlers.
-   This allows us to handle SIGSEGV signals generated when the
-   normal process stack is exhausted.  If this stack is not set
-   up (sigaltstack is unavailable or fails) and a SIGSEGV is
-   generated when the normal stack is exhausted then the program
-   will behave as though no SIGSEGV handler was installed.  */
+/* Start up the event loop.  This is the entry point to the event loop
+   from the command loop.  */
 
 static void
-setup_alternate_signal_stack (void)
+start_event_loop ()
 {
-#ifdef HAVE_SIGALTSTACK
-  stack_t ss;
+  /* Loop until there is nothing to do.  This is the entry point to
+     the event loop engine.  gdb_do_one_event will process one event
+     for each invocation.  It blocks waiting for an event and then
+     processes it.  */
+  while (1)
+    {
+      int result = 0;
 
-  /* FreeBSD versions older than 11.0 use char * for ss_sp instead of
-     void *.  This cast works with both types.  */
-  ss.ss_sp = (char *) xmalloc (SIGSTKSZ);
-  ss.ss_size = SIGSTKSZ;
-  ss.ss_flags = 0;
+      try
+       {
+         result = gdb_do_one_event ();
+       }
+      catch (const gdb_exception &ex)
+       {
+         exception_print (gdb_stderr, ex);
 
-  sigaltstack(&ss, NULL);
-#endif
+         /* If any exception escaped to here, we better enable
+            stdin.  Otherwise, any command that calls async_disable_stdin,
+            and then throws, will leave stdin inoperable.  */
+         SWITCH_THRU_ALL_UIS ()
+           {
+             async_enable_stdin ();
+           }
+         /* If we long-jumped out of do_one_event, we probably didn't
+            get around to resetting the prompt, which leaves readline
+            in a messed-up state.  Reset it here.  */
+         current_ui->prompt_state = PROMPT_NEEDED;
+         gdb::observers::command_error.notify ();
+         /* This call looks bizarre, but it is required.  If the user
+            entered a command that caused an error,
+            after_char_processing_hook won't be called from
+            rl_callback_read_char_wrapper.  Using a cleanup there
+            won't work, since we want this function to be called
+            after a new prompt is printed.  */
+         if (after_char_processing_hook)
+           (*after_char_processing_hook) ();
+         /* Maybe better to set a flag to be checked somewhere as to
+            whether display the prompt or not.  */
+       }
+
+      if (result < 0)
+       break;
+    }
+
+  /* We are done with the event loop.  There are no more event sources
+     to listen to.  So we exit GDB.  */
+  return;
 }
 
 /* Call command_loop.  */
@@ -596,14 +631,9 @@ captured_main_1 (struct captured_main_args *context)
   gdb_datadir = relocate_gdb_directory (GDB_DATADIR,
                                        GDB_DATADIR_RELOCATABLE);
 
-#ifdef WITH_PYTHON_PATH
-  {
-    /* For later use in helping Python find itself.  */
-    char *tmp = concat (WITH_PYTHON_PATH, SLASH_STRING, "lib", (char *) NULL);
-
-    python_libdir = relocate_gdb_directory (tmp, PYTHON_PATH_RELOCATABLE);
-    xfree (tmp);
-  }
+#ifdef WITH_PYTHON_LIBDIR
+  python_libdir = relocate_gdb_directory (WITH_PYTHON_LIBDIR,
+                                         PYTHON_LIBDIR_RELOCATABLE);
 #endif
 
 #ifdef RELOC_SRCDIR
@@ -898,7 +928,7 @@ captured_main_1 (struct captured_main_args *context)
   save_original_signals_state (quiet);
 
   /* Try to set up an alternate signal stack for SIGSEGV handlers.  */
-  setup_alternate_signal_stack ();
+  gdb::alternate_signal_stack signal_stack;
 
   /* Initialize all files.  */
   gdb_init (gdb_program_name);
@@ -976,7 +1006,6 @@ captured_main_1 (struct captured_main_args *context)
   if (print_help)
     {
       print_gdb_help (gdb_stdout);
-      fputs_unfiltered ("\n", gdb_stdout);
       exit (0);
     }
 
@@ -1362,7 +1391,11 @@ For more information, type \"help\" from within GDB, or consult the\n\
 GDB manual (available as on-line info or a printed manual).\n\
 "), stream);
   if (REPORT_BUGS_TO[0] && stream == gdb_stdout)
-    fprintf_unfiltered (stream, _("\
-Report bugs to \"%s\".\n\
+    fprintf_unfiltered (stream, _("\n\
+Report bugs to %s.\n\
 "), REPORT_BUGS_TO);
+  if (stream == gdb_stdout)
+    fprintf_unfiltered (stream, _("\n\
+You can ask GDB-related questions on the GDB users mailing list\n\
+(gdb@sourceware.org) or on GDB's IRC channel (#gdb on Freenode).\n"));
 }