X-Git-Url: http://git.efficios.com/?a=blobdiff_plain;f=gdb%2Fexceptions.c;h=7e15551e015e5274cca83fbaeac897b12ee6f69c;hb=refs%2Fheads%2Fconcurrent-displaced-stepping-2020-04-01;hp=aed10a8e5fec845b8fd71eec381ac02ca94e6f3e;hpb=05ff989b0b012d3c83f5908dd9750e01a74cc3de;p=deliverable%2Fbinutils-gdb.git
diff --git a/gdb/exceptions.c b/gdb/exceptions.c
index aed10a8e5f..7e15551e01 100644
--- a/gdb/exceptions.c
+++ b/gdb/exceptions.c
@@ -1,14 +1,12 @@
/* Exception (throw catch) mechanism, for GDB, the GNU debugger.
- Copyright 1986, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995,
- 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005 Free
- Software Foundation, Inc.
+ Copyright (C) 1986-2020 Free Software Foundation, Inc.
This file is part of GDB.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
- the Free Software Foundation; either version 2 of the License, or
+ the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
@@ -17,535 +15,135 @@
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
- along with this program; if not, write to the Free Software
- Foundation, Inc., 59 Temple Place - Suite 330,
- Boston, MA 02111-1307, USA. */
+ along with this program. If not, see . */
#include "defs.h"
#include "exceptions.h"
-#include
#include "breakpoint.h"
#include "target.h"
#include "inferior.h"
#include "annotate.h"
#include "ui-out.h"
-#include "gdb_assert.h"
-#include "gdb_string.h"
+#include "serial.h"
+#include "gdbthread.h"
+#include "top.h"
+#include "gdbsupport/gdb_optional.h"
-const struct exception exception_none = { 0, NO_ERROR, NULL };
-
-/* One should use catch_errors rather than manipulating these
- directly. */
-#if defined(HAVE_SIGSETJMP)
-#define SIGJMP_BUF sigjmp_buf
-#define SIGSETJMP(buf) sigsetjmp((buf), 1)
-#define SIGLONGJMP(buf,val) siglongjmp((buf), (val))
-#else
-#define SIGJMP_BUF jmp_buf
-#define SIGSETJMP(buf) setjmp(buf)
-#define SIGLONGJMP(buf,val) longjmp((buf), (val))
-#endif
-
-/* Possible catcher states. */
-enum catcher_state {
- /* Initial state, a new catcher has just been created. */
- CATCHER_CREATED,
- /* The catch code is running. */
- CATCHER_RUNNING,
- CATCHER_RUNNING_1,
- /* The catch code threw an exception. */
- CATCHER_ABORTING
-};
-
-/* Possible catcher actions. */
-enum catcher_action {
- CATCH_ITER,
- CATCH_ITER_1,
- CATCH_THROWING
-};
-
-struct catcher
-{
- enum catcher_state state;
- /* Jump buffer pointing back at the exception handler. */
- SIGJMP_BUF buf;
- /* Status buffer belonging to the exception handler. */
- volatile struct exception *exception;
- /* Should the error / quit message be printed? Old code assumes
- that this file prints the error/quit message when first reported.
- New code instead directly handles the printing of error/quit
- messages. */
- int print_message;
- /* Saved/current state. */
- int mask;
- char *saved_error_pre_print;
- char *saved_quit_pre_print;
- struct ui_out *saved_uiout;
- struct cleanup *saved_cleanup_chain;
- /* Back link. */
- struct catcher *prev;
-};
-
-/* Where to go for throw_exception(). */
-static struct catcher *current_catcher;
-
-static SIGJMP_BUF *
-catcher_init (struct ui_out *func_uiout,
- char *errstring,
- volatile struct exception *exception,
- return_mask mask,
- int print_message)
+static void
+print_flush (void)
{
- struct catcher *new_catcher = XZALLOC (struct catcher);
+ struct ui *ui = current_ui;
+ struct serial *gdb_stdout_serial;
- /* Start with no exception, save it's address. */
- exception->reason = 0;
- exception->error = NO_ERROR;
- exception->message = NULL;
- new_catcher->exception = exception;
+ if (deprecated_error_begin_hook)
+ deprecated_error_begin_hook ();
- new_catcher->mask = mask;
- new_catcher->print_message = print_message;
+ gdb::optional term_state;
+ if (target_supports_terminal_ours ())
+ {
+ term_state.emplace ();
+ target_terminal::ours_for_output ();
+ }
- /* Override error/quit messages during FUNC. */
- new_catcher->saved_error_pre_print = error_pre_print;
- new_catcher->saved_quit_pre_print = quit_pre_print;
- if (mask & RETURN_MASK_ERROR)
- error_pre_print = errstring;
- if (mask & RETURN_MASK_QUIT)
- quit_pre_print = errstring;
+ /* We want all output to appear now, before we print the error. We
+ have 3 levels of buffering we have to flush (it's possible that
+ some of these should be changed to flush the lower-level ones
+ too): */
- /* Override the global ``struct ui_out'' builder. */
- new_catcher->saved_uiout = uiout;
- uiout = func_uiout;
+ /* 1. The _filtered buffer. */
+ if (filtered_printing_initialized ())
+ wrap_here ("");
- /* Prevent error/quit during FUNC from calling cleanups established
- prior to here. */
- new_catcher->saved_cleanup_chain = save_cleanups ();
+ /* 2. The stdio buffer. */
+ gdb_flush (gdb_stdout);
+ gdb_flush (gdb_stderr);
- /* Push this new catcher on the top. */
- new_catcher->prev = current_catcher;
- current_catcher = new_catcher;
- new_catcher->state = CATCHER_CREATED;
+ /* 3. The system-level buffer. */
+ gdb_stdout_serial = serial_fdopen (fileno (ui->outstream));
+ if (gdb_stdout_serial)
+ {
+ serial_drain_output (gdb_stdout_serial);
+ serial_un_fdopen (gdb_stdout_serial);
+ }
- return &new_catcher->buf;
+ annotate_error_begin ();
}
static void
-catcher_pop (void)
+print_exception (struct ui_file *file, const struct gdb_exception &e)
{
- struct catcher *old_catcher = current_catcher;
- current_catcher = old_catcher->prev;
+ /* KLUDGE: cagney/2005-01-13: Write the string out one line at a time
+ as that way the MI's behavior is preserved. */
+ const char *start;
+ const char *end;
- /* Restore the cleanup chain, the error/quit messages, and the uiout
- builder, to their original states. */
-
- restore_cleanups (old_catcher->saved_cleanup_chain);
-
- uiout = old_catcher->saved_uiout;
-
- quit_pre_print = old_catcher->saved_quit_pre_print;
- error_pre_print = old_catcher->saved_error_pre_print;
-
- xfree (old_catcher);
-}
-
-/* Catcher state machine. Returns non-zero if the m/c should be run
- again, zero if it should abort. */
-
-int
-catcher_state_machine (enum catcher_action action)
-{
- switch (current_catcher->state)
+ for (start = e.what (); start != NULL; start = end)
{
- case CATCHER_CREATED:
- switch (action)
- {
- case CATCH_ITER:
- /* Allow the code to run the catcher. */
- current_catcher->state = CATCHER_RUNNING;
- return 1;
- default:
- internal_error (__FILE__, __LINE__, "bad state");
- }
- case CATCHER_RUNNING:
- switch (action)
+ end = strchr (start, '\n');
+ if (end == NULL)
+ fputs_filtered (start, file);
+ else
{
- case CATCH_ITER:
- /* No error/quit has occured. Just clean up. */
- catcher_pop ();
- return 0;
- case CATCH_ITER_1:
- current_catcher->state = CATCHER_RUNNING_1;
- return 1;
- case CATCH_THROWING:
- current_catcher->state = CATCHER_ABORTING;
- /* See also throw_exception. */
- return 1;
- default:
- internal_error (__FILE__, __LINE__, "bad switch");
+ end++;
+ file->write (start, end - start);
}
- case CATCHER_RUNNING_1:
- switch (action)
- {
- case CATCH_ITER:
- /* The did a "break" from the inner while loop. */
- catcher_pop ();
- return 0;
- case CATCH_ITER_1:
- current_catcher->state = CATCHER_RUNNING;
- return 0;
- case CATCH_THROWING:
- current_catcher->state = CATCHER_ABORTING;
- /* See also throw_exception. */
- return 1;
- default:
- internal_error (__FILE__, __LINE__, "bad switch");
- }
- case CATCHER_ABORTING:
- switch (action)
- {
- case CATCH_ITER:
- {
- struct exception exception = *current_catcher->exception;
- if (current_catcher->mask & RETURN_MASK (exception.reason))
- {
- /* Exit normally if this catcher can handle this
- exception. The caller analyses the func return
- values. */
- catcher_pop ();
- return 0;
- }
- /* The caller didn't request that the event be caught,
- relay the event to the next containing
- catch_errors(). */
- catcher_pop ();
- throw_exception (exception);
- }
- default:
- internal_error (__FILE__, __LINE__, "bad state");
- }
- default:
- internal_error (__FILE__, __LINE__, "bad switch");
- }
-}
-
-/* Return EXCEPTION to the nearest containing catch_errors(). */
-
-NORETURN void
-throw_exception (struct exception exception)
-{
- quit_flag = 0;
- immediate_quit = 0;
-
- /* Perhaps it would be cleaner to do this via the cleanup chain (not sure
- I can think of a reason why that is vital, though). */
- bpstat_clear_actions (stop_bpstat); /* Clear queued breakpoint commands */
+ }
+ fprintf_filtered (file, "\n");
- disable_current_display ();
- do_cleanups (ALL_CLEANUPS);
- if (target_can_async_p () && !target_executing)
- do_exec_cleanups (ALL_CLEANUPS);
- if (sync_execution)
- do_exec_error_cleanups (ALL_CLEANUPS);
-
- if (annotation_level > 1)
- switch (exception.reason)
- {
- case RETURN_QUIT:
- annotate_quit ();
- break;
- case RETURN_ERROR:
- /* Assume that these are all errors. */
- annotate_error ();
- break;
- default:
- internal_error (__FILE__, __LINE__, "Bad switch.");
- }
-
- /* Jump to the containing catch_errors() call, communicating REASON
- to that call via setjmp's return value. Note that REASON can't
- be zero, by definition in defs.h. */
- catcher_state_machine (CATCH_THROWING);
- *current_catcher->exception = exception;
- SIGLONGJMP (current_catcher->buf, exception.reason);
-}
-
-static char *last_message;
-
-NORETURN void
-throw_reason (enum return_reason reason)
-{
- struct exception exception;
- memset (&exception, 0, sizeof exception);
-
- exception.reason = reason;
- switch (reason)
+ /* Now append the annotation. */
+ switch (e.reason)
{
case RETURN_QUIT:
+ annotate_quit ();
break;
case RETURN_ERROR:
- exception.error = GENERIC_ERROR;
- exception.message = last_message;
+ /* Assume that these are all errors. */
+ annotate_error ();
break;
default:
- internal_error (__FILE__, __LINE__, "bad switch");
+ internal_error (__FILE__, __LINE__, _("Bad switch."));
}
-
- throw_exception (exception);
-}
-
-static void
-do_write (void *data, const char *buffer, long length_buffer)
-{
- ui_file_write (data, buffer, length_buffer);
}
-
void
-exception_print (struct ui_file *file, const char *pre_print,
- struct exception e)
+exception_print (struct ui_file *file, const struct gdb_exception &e)
{
if (e.reason < 0 && e.message != NULL)
{
- target_terminal_ours ();
- wrap_here (""); /* Force out any buffered output */
- gdb_flush (file);
- annotate_error_begin ();
- if (pre_print)
- fputs_filtered (pre_print, file);
-
- /* KLUGE: cagney/2005-01-13: Write the string out one line at a
- time as that way the MI's behavior is preserved. */
- {
- const char *start;
- const char *end;
- for (start = e.message; start != NULL; start = end)
- {
- end = strchr (start, '\n');
- if (end == NULL)
- fputs_filtered (start, file);
- else
- {
- end++;
- ui_file_write (file, start, end - start);
- }
- }
- }
- fprintf_filtered (file, "\n");
+ print_flush ();
+ print_exception (file, e);
}
}
-NORETURN static void
-print_and_throw (enum return_reason reason, enum errors error,
- const char *prefix, const char *fmt,
- va_list ap) ATTR_NORETURN;
-NORETURN static void
-print_and_throw (enum return_reason reason, enum errors error,
- const char *prefix, const char *fmt, va_list ap)
+void
+exception_fprintf (struct ui_file *file, const struct gdb_exception &e,
+ const char *prefix, ...)
{
- /* FIXME: cagney/2005-01-13: While xstrvprintf is simpler it alters
- GDB's output. Instead of the message being printed
- line-at-a-time the message comes out all at once. The problem is
- that the MI testsuite is checks for line-at-a-time messages and
- changing this behavior means updating the testsuite. */
-
- struct exception e;
- struct ui_file *tmp_stream;
- long len;
-
- /* Convert the message into a print stream. */
- tmp_stream = mem_fileopen ();
- make_cleanup_ui_file_delete (tmp_stream);
- vfprintf_unfiltered (tmp_stream, fmt, ap);
-
- /* Save the message. */
- xfree (last_message);
- last_message = ui_file_xstrdup (tmp_stream, &len);
-
- /* Print the mesage to stderr, but only if the catcher isn't going
- to handle/print it locally. */
- if (current_catcher->print_message)
+ if (e.reason < 0 && e.message != NULL)
{
- if (deprecated_error_begin_hook)
- deprecated_error_begin_hook ();
-
- /* Write the message plus any pre_print to gdb_stderr. */
- target_terminal_ours ();
- wrap_here (""); /* Force out any buffered output */
- gdb_flush (gdb_stdout);
- annotate_error_begin ();
- if (error_pre_print)
- fputs_filtered (error_pre_print, gdb_stderr);
- ui_file_put (tmp_stream, do_write, gdb_stderr);
- fprintf_filtered (gdb_stderr, "\n");
- }
-
- /* Throw the exception. */
- e.reason = reason;
- e.error = error;
- e.message = last_message;
- throw_exception (e);
-}
-
-NORETURN void
-throw_verror (enum errors error, const char *fmt, va_list ap)
-{
- print_and_throw (RETURN_ERROR, error, error_pre_print, fmt, ap);
-}
-
-NORETURN void
-throw_vfatal (const char *fmt, va_list ap)
-{
- print_and_throw (RETURN_QUIT, NO_ERROR, quit_pre_print, fmt, ap);
-}
-
-NORETURN void
-throw_error (enum errors error, const char *fmt, ...)
-{
- va_list args;
- va_start (args, fmt);
- print_and_throw (RETURN_ERROR, error, error_pre_print, fmt, args);
- va_end (args);
-}
-
-/* Call FUNC() with args FUNC_UIOUT and FUNC_ARGS, catching any
- errors. Set FUNC_CAUGHT to an ``enum return_reason'' if the
- function is aborted (using throw_exception() or zero if the
- function returns normally. Set FUNC_VAL to the value returned by
- the function or 0 if the function was aborted.
+ va_list args;
- Must not be called with immediate_quit in effect (bad things might
- happen, say we got a signal in the middle of a memcpy to quit_return).
- This is an OK restriction; with very few exceptions immediate_quit can
- be replaced by judicious use of QUIT.
+ print_flush ();
- MASK specifies what to catch; it is normally set to
- RETURN_MASK_ALL, if for no other reason than that the code which
- calls catch_errors might not be set up to deal with a quit which
- isn't caught. But if the code can deal with it, it generally
- should be RETURN_MASK_ERROR, unless for some reason it is more
- useful to abort only the portion of the operation inside the
- catch_errors. Note that quit should return to the command line
- fairly quickly, even if some further processing is being done. */
+ /* Print the prefix. */
+ va_start (args, prefix);
+ vfprintf_filtered (file, prefix, args);
+ va_end (args);
-/* MAYBE: cagney/1999-11-05: catch_errors() in conjunction with
- error() et.al. could maintain a set of flags that indicate the the
- current state of each of the longjmp buffers. This would give the
- longjmp code the chance to detect a longjmp botch (before it gets
- to longjmperror()). Prior to 1999-11-05 this wasn't possible as
- code also randomly used a SET_TOP_LEVEL macro that directly
- initialize the longjmp buffers. */
-
-/* MAYBE: cagney/1999-11-05: Should the catch_errors and cleanups code
- be consolidated into a single file instead of being distributed
- between utils.c and top.c? */
-
-int
-catch_exceptions (struct ui_out *uiout,
- catch_exceptions_ftype *func,
- void *func_args,
- char *errstring,
- return_mask mask)
-{
- return catch_exceptions_with_msg (uiout, func, func_args, errstring,
- NULL, mask);
-}
-
-struct exception
-catch_exception (struct ui_out *uiout,
- catch_exception_ftype *func,
- void *func_args,
- return_mask mask)
-{
- volatile struct exception exception;
- SIGJMP_BUF *catch;
- catch = catcher_init (uiout, NULL, &exception, mask, 0);
- for (SIGSETJMP ((*catch));
- catcher_state_machine (CATCH_ITER);)
- (*func) (uiout, func_args);
- return exception;
-}
-
-int
-catch_exceptions_with_msg (struct ui_out *uiout,
- catch_exceptions_ftype *func,
- void *func_args,
- char *errstring,
- char **gdberrmsg,
- return_mask mask)
-{
- volatile struct exception exception;
- volatile int val = 0;
- SIGJMP_BUF *catch = catcher_init (uiout, errstring, &exception, mask, 1);
- for (SIGSETJMP ((*catch)); catcher_state_machine (CATCH_ITER);)
- val = (*func) (uiout, func_args);
- gdb_assert (val >= 0);
- gdb_assert (exception.reason <= 0);
- if (exception.reason < 0)
- {
- /* If caller wants a copy of the low-level error message, make
- one. This is used in the case of a silent error whereby the
- caller may optionally want to issue the message. */
- if (gdberrmsg != NULL)
- {
- if (exception.message != NULL)
- *gdberrmsg = xstrdup (exception.message);
- else
- *gdberrmsg = NULL;
- }
- return exception.reason;
+ print_exception (file, e);
}
- return val;
}
-int
-catch_errors (catch_errors_ftype *func, void *func_args, char *errstring,
- return_mask mask)
-{
- volatile int val = 0;
- volatile struct exception exception;
- SIGJMP_BUF *catch = catcher_init (uiout, errstring, &exception, mask, 1);
- /* This illustrates how it is possible to nest the mechanism and
- hence catch "break". Of course this doesn't address the need to
- also catch "return". */
- for (SIGSETJMP ((*catch)); catcher_state_machine (CATCH_ITER);)
- val = func (func_args);
- if (exception.reason != 0)
- return 0;
- return val;
-}
-
-struct captured_command_args
- {
- catch_command_errors_ftype *command;
- char *arg;
- int from_tty;
- };
-
-static int
-do_captured_command (void *data)
-{
- struct captured_command_args *context = data;
- context->command (context->arg, context->from_tty);
- /* FIXME: cagney/1999-11-07: Technically this do_cleanups() call
- isn't needed. Instead an assertion check could be made that
- simply confirmed that the called function correctly cleaned up
- after itself. Unfortunately, old code (prior to 1999-11-04) in
- main.c was calling SET_TOP_LEVEL(), calling the command function,
- and then *always* calling do_cleanups(). For the moment we
- remain ``bug compatible'' with that old code.. */
- do_cleanups (ALL_CLEANUPS);
- return 1;
-}
+/* See exceptions.h. */
int
-catch_command_errors (catch_command_errors_ftype * command,
- char *arg, int from_tty, return_mask mask)
+exception_print_same (const struct gdb_exception &e1,
+ const struct gdb_exception &e2)
{
- struct captured_command_args args;
- args.command = command;
- args.arg = arg;
- args.from_tty = from_tty;
- return catch_errors (do_captured_command, &args, "", mask);
+ const char *msg1 = e1.message == nullptr ? "" : e1.what ();
+ const char *msg2 = e2.message == nullptr ? "" : e2.what ();
+
+ return (e1.reason == e2.reason
+ && e1.error == e2.error
+ && strcmp (msg1, msg2) == 0);
}