262 lines
9.0 KiB
C++
262 lines
9.0 KiB
C++
/* Exception (throw catch) mechanism, for GDB, the GNU debugger.
|
|
|
|
Copyright (C) 1986-2013 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 3 of the License, or
|
|
(at your option) any later version.
|
|
|
|
This program is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
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, see <http://www.gnu.org/licenses/>. */
|
|
|
|
#ifndef EXCEPTIONS_H
|
|
#define EXCEPTIONS_H
|
|
|
|
#include "ui-out.h"
|
|
#include <setjmp.h>
|
|
|
|
/* Reasons for calling throw_exceptions(). NOTE: all reason values
|
|
must be less than zero. enum value 0 is reserved for internal use
|
|
as the return value from an initial setjmp(). The function
|
|
catch_exceptions() reserves values >= 0 as legal results from its
|
|
wrapped function. */
|
|
|
|
enum return_reason
|
|
{
|
|
/* User interrupt. */
|
|
RETURN_QUIT = -2,
|
|
/* Any other error. */
|
|
RETURN_ERROR
|
|
};
|
|
|
|
#define RETURN_MASK(reason) (1 << (int)(-reason))
|
|
#define RETURN_MASK_QUIT RETURN_MASK (RETURN_QUIT)
|
|
#define RETURN_MASK_ERROR RETURN_MASK (RETURN_ERROR)
|
|
#define RETURN_MASK_ALL (RETURN_MASK_QUIT | RETURN_MASK_ERROR)
|
|
typedef int return_mask;
|
|
|
|
/* Describe all exceptions. */
|
|
|
|
enum errors {
|
|
GDB_NO_ERROR,
|
|
|
|
/* Any generic error, the corresponding text is in
|
|
exception.message. */
|
|
GENERIC_ERROR,
|
|
|
|
/* Something requested was not found. */
|
|
NOT_FOUND_ERROR,
|
|
|
|
/* Thread library lacks support necessary for finding thread local
|
|
storage. */
|
|
TLS_NO_LIBRARY_SUPPORT_ERROR,
|
|
|
|
/* Load module not found while attempting to find thread local storage. */
|
|
TLS_LOAD_MODULE_NOT_FOUND_ERROR,
|
|
|
|
/* Thread local storage has not been allocated yet. */
|
|
TLS_NOT_ALLOCATED_YET_ERROR,
|
|
|
|
/* Something else went wrong while attempting to find thread local
|
|
storage. The ``struct gdb_exception'' message field provides
|
|
more detail. */
|
|
TLS_GENERIC_ERROR,
|
|
|
|
/* Problem parsing an XML document. */
|
|
XML_PARSE_ERROR,
|
|
|
|
/* Error accessing memory. */
|
|
MEMORY_ERROR,
|
|
|
|
/* Feature is not supported in this copy of GDB. */
|
|
UNSUPPORTED_ERROR,
|
|
|
|
/* Value not available. E.g., a register was not collected in a
|
|
traceframe. */
|
|
NOT_AVAILABLE_ERROR,
|
|
|
|
/* DW_OP_GNU_entry_value resolving failed. */
|
|
NO_ENTRY_VALUE_ERROR,
|
|
|
|
/* Target throwing an error has been closed. Current command should be
|
|
aborted as the inferior state is no longer valid. */
|
|
TARGET_CLOSE_ERROR,
|
|
|
|
/* Add more errors here. */
|
|
NR_ERRORS
|
|
};
|
|
|
|
struct gdb_exception
|
|
{
|
|
enum return_reason reason;
|
|
enum errors error;
|
|
const char *message;
|
|
};
|
|
|
|
/* A pre-defined non-exception. */
|
|
extern const struct gdb_exception exception_none;
|
|
|
|
/* Wrap set/long jmp so that it's more portable (internal to
|
|
exceptions). */
|
|
|
|
#if defined(HAVE_SIGSETJMP)
|
|
#define EXCEPTIONS_SIGJMP_BUF sigjmp_buf
|
|
#define EXCEPTIONS_SIGSETJMP(buf) sigsetjmp((buf), 1)
|
|
#define EXCEPTIONS_SIGLONGJMP(buf,val) siglongjmp((buf), (val))
|
|
#else
|
|
#define EXCEPTIONS_SIGJMP_BUF jmp_buf
|
|
#define EXCEPTIONS_SIGSETJMP(buf) setjmp(buf)
|
|
#define EXCEPTIONS_SIGLONGJMP(buf,val) longjmp((buf), (val))
|
|
#endif
|
|
|
|
/* Functions to drive the exceptions state m/c (internal to
|
|
exceptions). */
|
|
EXCEPTIONS_SIGJMP_BUF *exceptions_state_mc_init (volatile struct
|
|
gdb_exception *exception,
|
|
return_mask mask);
|
|
int exceptions_state_mc_action_iter (void);
|
|
int exceptions_state_mc_action_iter_1 (void);
|
|
|
|
/* Macro to wrap up standard try/catch behavior.
|
|
|
|
The double loop lets us correctly handle code "break"ing out of the
|
|
try catch block. (It works as the "break" only exits the inner
|
|
"while" loop, the outer for loop detects this handling it
|
|
correctly.) Of course "return" and "goto" are not so lucky.
|
|
|
|
For instance:
|
|
|
|
*INDENT-OFF*
|
|
|
|
volatile struct gdb_exception e;
|
|
TRY_CATCH (e, RETURN_MASK_ERROR)
|
|
{
|
|
}
|
|
switch (e.reason)
|
|
{
|
|
case RETURN_ERROR: ...
|
|
}
|
|
|
|
*/
|
|
|
|
#define TRY_CATCH(EXCEPTION,MASK) \
|
|
{ \
|
|
EXCEPTIONS_SIGJMP_BUF *buf = \
|
|
exceptions_state_mc_init (&(EXCEPTION), (MASK)); \
|
|
EXCEPTIONS_SIGSETJMP (*buf); \
|
|
} \
|
|
while (exceptions_state_mc_action_iter ()) \
|
|
while (exceptions_state_mc_action_iter_1 ())
|
|
|
|
/* *INDENT-ON* */
|
|
|
|
|
|
/* If E is an exception, print it's error message on the specified
|
|
stream. For _fprintf, prefix the message with PREFIX... */
|
|
extern void exception_print (struct ui_file *file, struct gdb_exception e);
|
|
extern void exception_fprintf (struct ui_file *file, struct gdb_exception e,
|
|
const char *prefix,
|
|
...) ATTRIBUTE_PRINTF (3, 4);
|
|
|
|
/* Throw an exception (as described by "struct gdb_exception"). Will
|
|
execute a LONG JUMP to the inner most containing exception handler
|
|
established using catch_exceptions() (or similar).
|
|
|
|
Code normally throws an exception using error() et.al. For various
|
|
reaons, GDB also contains code that throws an exception directly.
|
|
For instance, the remote*.c targets contain CNTRL-C signal handlers
|
|
that propogate the QUIT event up the exception chain. ``This could
|
|
be a good thing or a dangerous thing.'' -- the Existential
|
|
Wombat. */
|
|
|
|
extern void throw_exception (struct gdb_exception exception)
|
|
ATTRIBUTE_NORETURN;
|
|
extern void throw_verror (enum errors, const char *fmt, va_list ap)
|
|
ATTRIBUTE_NORETURN ATTRIBUTE_PRINTF (2, 0);
|
|
extern void throw_vfatal (const char *fmt, va_list ap)
|
|
ATTRIBUTE_NORETURN ATTRIBUTE_PRINTF (1, 0);
|
|
extern void throw_error (enum errors error, const char *fmt, ...)
|
|
ATTRIBUTE_NORETURN ATTRIBUTE_PRINTF (2, 3);
|
|
|
|
/* Call FUNC(UIOUT, FUNC_ARGS) but wrapped within an exception
|
|
handler. If an exception (enum return_reason) is thrown using
|
|
throw_exception() than all cleanups installed since
|
|
catch_exceptions() was entered are invoked, the (-ve) exception
|
|
value is then returned by catch_exceptions. If FUNC() returns
|
|
normally (with a positive or zero return value) then that value is
|
|
returned by catch_exceptions(). It is an internal_error() for
|
|
FUNC() to return a negative value.
|
|
|
|
For the period of the FUNC() call: UIOUT is installed as the output
|
|
builder; ERRSTRING is installed as the error/quit message; and a
|
|
new cleanup_chain is established. The old values are restored
|
|
before catch_exceptions() returns.
|
|
|
|
The variant catch_exceptions_with_msg() is the same as
|
|
catch_exceptions() but adds the ability to return an allocated
|
|
copy of the gdb error message. This is used when a silent error is
|
|
issued and the caller wants to manually issue the error message.
|
|
|
|
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.
|
|
|
|
FIXME; cagney/2001-08-13: The need to override the global UIOUT
|
|
builder variable should just go away.
|
|
|
|
This function supersedes catch_errors().
|
|
|
|
This function uses SETJMP() and LONGJUMP(). */
|
|
|
|
struct ui_out;
|
|
typedef int (catch_exceptions_ftype) (struct ui_out *ui_out, void *args);
|
|
extern int catch_exceptions (struct ui_out *uiout,
|
|
catch_exceptions_ftype *func, void *func_args,
|
|
return_mask mask);
|
|
typedef void (catch_exception_ftype) (struct ui_out *ui_out, void *args);
|
|
extern int catch_exceptions_with_msg (struct ui_out *uiout,
|
|
catch_exceptions_ftype *func,
|
|
void *func_args,
|
|
char **gdberrmsg,
|
|
return_mask mask);
|
|
|
|
/* If CATCH_ERRORS_FTYPE throws an error, catch_errors() returns zero
|
|
otherwize the result from CATCH_ERRORS_FTYPE is returned. It is
|
|
probably useful for CATCH_ERRORS_FTYPE to always return a non-zero
|
|
value. It's unfortunate that, catch_errors() does not return an
|
|
indication of the exact exception that it caught - quit_flag might
|
|
help.
|
|
|
|
This function is superseded by catch_exceptions(). */
|
|
|
|
typedef int (catch_errors_ftype) (void *);
|
|
extern int catch_errors (catch_errors_ftype *, void *, char *, return_mask);
|
|
|
|
/* Template to catch_errors() that wraps calls to command
|
|
functions. */
|
|
|
|
typedef void (catch_command_errors_ftype) (char *, int);
|
|
extern int catch_command_errors (catch_command_errors_ftype *func,
|
|
char *arg, int from_tty, return_mask);
|
|
|
|
/* Like catch_command_errors, but works with const command and args. */
|
|
|
|
typedef void (catch_command_errors_const_ftype) (const char *, int);
|
|
extern int catch_command_errors_const (catch_command_errors_const_ftype *func,
|
|
const char *arg, int from_tty, return_mask);
|
|
|
|
#endif
|