gdb/exceptions.c

   1 /* Exception (throw catch) mechanism, for GDB, the GNU debugger.
   2
   3    Copyright (C) 1986-2019 Free Software Foundation, Inc.
   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
  22 /* Local non-gdb includes.  */
  23 #include "annotate.h"
  24 #include "breakpoint.h"
  25 #include "common/gdb_optional.h"
  26 #include "exceptions.h"
  27 #include "gdbthread.h"
  28 #include "inferior.h"
  29 #include "serial.h"
  30 #include "target.h"
  31 #include "top.h"
  32 #include "ui-out.h"
  33
  34 static void
  35 print_flush (void)
  36 {
  37   struct ui *ui = current_ui;
  38   struct serial *gdb_stdout_serial;
  39
  40   if (deprecated_error_begin_hook)
  41     deprecated_error_begin_hook ();
  42
  43   gdb::optional<target_terminal::scoped_restore_terminal_state> term_state;
  44   /* While normally there's always something pushed on the target
  45      stack, the NULL check is needed here because we can get here very
  46      early during startup, before the target stack is first
  47      initialized.  */
  48   if (current_top_target () != NULL && target_supports_terminal_ours ())
  49     {
  50       term_state.emplace ();
  51       target_terminal::ours_for_output ();
  52     }
  53
  54   /* We want all output to appear now, before we print the error.  We
  55      have 3 levels of buffering we have to flush (it's possible that
  56      some of these should be changed to flush the lower-level ones
  57      too):  */
  58
  59   /* 1.  The _filtered buffer.  */
  60   if (filtered_printing_initialized ())
  61     wrap_here ("");
  62
  63   /* 2.  The stdio buffer.  */
  64   gdb_flush (gdb_stdout);
  65   gdb_flush (gdb_stderr);
  66
  67   /* 3.  The system-level buffer.  */
  68   gdb_stdout_serial = serial_fdopen (fileno (ui->outstream));
  69   if (gdb_stdout_serial)
  70     {
  71       serial_drain_output (gdb_stdout_serial);
  72       serial_un_fdopen (gdb_stdout_serial);
  73     }
  74
  75   annotate_error_begin ();
  76 }
  77
  78 static void
  79 print_exception (struct ui_file *file, struct gdb_exception e)
  80 {
  81   /* KLUGE: cagney/2005-01-13: Write the string out one line at a time
  82      as that way the MI's behavior is preserved.  */
  83   const char *start;
  84   const char *end;
  85
  86   for (start = e.message; start != NULL; start = end)
  87     {
  88       end = strchr (start, '\n');
  89       if (end == NULL)
  90         fputs_filtered (start, file);
  91       else
  92         {
  93           end++;
  94           ui_file_write (file, start, end - start);
  95         }
  96     }
  97   fprintf_filtered (file, "\n");
  98
  99   /* Now append the annotation.  */
 100   switch (e.reason)
 101     {
 102     case RETURN_QUIT:
 103       annotate_quit ();
 104       break;
 105     case RETURN_ERROR:
 106       /* Assume that these are all errors.  */
 107       annotate_error ();
 108       break;
 109     default:
 110       internal_error (__FILE__, __LINE__, _("Bad switch."));
 111     }
 112 }
 113
 114 void
 115 exception_print (struct ui_file *file, struct gdb_exception e)
 116 {
 117   if (e.reason < 0 && e.message != NULL)
 118     {
 119       print_flush ();
 120       print_exception (file, e);
 121     }
 122 }
 123
 124 void
 125 exception_fprintf (struct ui_file *file, struct gdb_exception e,
 126                    const char *prefix, ...)
 127 {
 128   if (e.reason < 0 && e.message != NULL)
 129     {
 130       va_list args;
 131
 132       print_flush ();
 133
 134       /* Print the prefix.  */
 135       va_start (args, prefix);
 136       vfprintf_filtered (file, prefix, args);
 137       va_end (args);
 138
 139       print_exception (file, e);
 140     }
 141 }
 142
 143 /* See exceptions.h.  */
 144
 145 int
 146 exception_print_same (struct gdb_exception e1, struct gdb_exception e2)
 147 {
 148   const char *msg1 = e1.message;
 149   const char *msg2 = e2.message;
 150
 151   if (msg1 == NULL)
 152     msg1 = "";
 153   if (msg2 == NULL)
 154     msg2 = "";
 155
 156   return (e1.reason == e2.reason
 157           && e1.error == e2.error
 158           && strcmp (msg1, msg2) == 0);
 159 }