-/*
-** OSSP ex - Exception Handling (modified to fit into SimGrid)
-** Copyright (c) 2005 Martin Quinson.
-** Copyright (c) 2002-2004 Ralf S. Engelschall <rse@engelschall.com>
-** Copyright (c) 2002-2004 The OSSP Project <http://www.ossp.org/>
-** Copyright (c) 2002-2004 Cable & Wireless <http://www.cw.com/>
-**
-** This file is part of OSSP ex, an exception handling library
-** which can be found at http://www.ossp.org/pkg/lib/ex/.
-**
-** Permission to use, copy, modify, and distribute this software for
-** any purpose with or without fee is hereby granted, provided that
-** the above copyright notice and this permission notice appear in all
-** copies.
-**
-** THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
-** WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
-** MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
-** IN NO EVENT SHALL THE AUTHORS AND COPYRIGHT HOLDERS AND THEIR
-** CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
-** USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
-** ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
-** OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
-** OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
-** SUCH DAMAGE.
-**
-** ex.h: exception handling (pre-processor part)
-*/
+/* Copyright (c) 2005-2020. The SimGrid Team. All rights reserved. */
-#ifndef __XBT_EX_H__
-#define __XBT_EX_H__
+/* This program is free software; you can redistribute it and/or modify it
+ * under the terms of the license (GNU LGPL) which comes with this package. */
-#include <xbt/misc.h>
-#include <xbt/sysdep.h>
-
-/* required ISO-C standard facilities */
-#include <stdio.h>
-
-/* the machine context */
-#if defined(__EX_MCTX_MCSC__)
-#include <ucontext.h> /* POSIX.1 ucontext(3) */
-#define __ex_mctx_struct ucontext_t uc;
-#define __ex_mctx_save(mctx) (getcontext(&(mctx)->uc) == 0)
-#define __ex_mctx_restored(mctx) /* noop */
-#define __ex_mctx_restore(mctx) (void)setcontext(&(mctx)->uc)
+#ifndef XBT_EX_H
+#define XBT_EX_H
-#elif defined(__EX_MCTX_SSJLJ__)
-#include <setjmp.h> /* POSIX.1 sigjmp_buf(3) */
-#define __ex_mctx_struct sigjmp_buf jb;
-#define __ex_mctx_save(mctx) (sigsetjmp((mctx)->jb, 1) == 0)
-#define __ex_mctx_restored(mctx) /* noop */
-#define __ex_mctx_restore(mctx) (void)siglongjmp((mctx)->jb, 1)
+#include <stdlib.h>
-#elif defined(__EX_MCTX_SJLJ__) || !defined(__EX_MCTX_CUSTOM__)
-#include <setjmp.h> /* ISO-C jmp_buf(3) */
-#define __ex_mctx_struct jmp_buf jb;
-#define __ex_mctx_save(mctx) (setjmp((mctx)->jb) == 0)
-#define __ex_mctx_restored(mctx) /* noop */
-#define __ex_mctx_restore(mctx) (void)longjmp((mctx)->jb, 1)
-#endif
-
-/* declare the machine context type */
-typedef struct { __ex_mctx_struct } __ex_mctx_t;
-/** @addtogroup XBT_ex
- *
- * This module is a small ISO-C++ style exception handling library
- * for use in the ISO-C language. It allows you to use the paradigm
- * of throwing and catching exceptions in order to reduce the amount
- * of error handling code without hindering program robustness.
- *
- * This is achieved by directly transferring exceptional return codes
- * (and the program control flow) from the location where the exception
- * is raised (throw point) to the location where it is handled (catch
- * point) -- usually from a deeply nested sub-routine to a parent
- * routine. All intermediate routines no longer have to make sure that
- * the exceptional return codes from sub-routines are correctly passed
- * back to the parent.
- *
- * These features are brought to you by a modified version of the libex
- * library, one of the numerous masterpiece of Ralf S. Engelschall.
- *
- * @section XBT_ex_intro DESCRIPTION
- *
- * In SimGrid, exceptions is a triple <\a msg , \a category , \a value>
- * where \a msg is a human-readable text describing the exceptional
- * condition, \a code an integer describing what went wrong and \a value
- * providing a sort of sub-category. (this is different in the original libex).
- *
- * @section XBT_ex_base BASIC USAGE
- *
- * \em TRY \b TRIED_BLOCK [\em CLEANUP \b CLEANUP_BLOCK] \em CATCH (variable) \b CATCH_BLOCK
- *
- * This is the primary syntactical construct provided. It is modeled after the
- * ISO-C++ try-catch clause and should sound familiar to most of you.
- *
- * Any exception thrown directly from the TRIED_BLOCK block or from called
- * subroutines is caught. Cleanups which must be done after this block
- * (whenever an exception arised or not) should be placed into the optionnal
- * CLEANUP_BLOCK. The code dealing with the exceptions when they arise should
- * be placed into the (mandatory) CATCH_BLOCK.
- *
- *
- * In absence of exception, the control flow goes into the blocks TRIED_BLOCK
- * and CLEANUP_BLOCK (if present); The CATCH_BLOCK block is then ignored.
- *
- * When an exception is thrown, the control flow goes through the following
- * blocks: TRIED_BLOCK (up to the statement throwing the exception),
- * CLEANUP_BLOCK (if any) and CATCH_BLOCK. The exception is stored in a
- * variable for inspection inside the CATCH_BLOCK. This variable must be
- * declared in the outter scope, but its value is only valid within the
- * CATCH_BLOCK block.
- *
- * Some notes:
- * - TRY, CLEANUP and CATCH cannot be used separately, they work
- * only in combination and form a language clause as a whole.
- * - In contrast to the syntax of other languages (such as C++ or Jave) there
- * is only one CATCH block and not multiple ones (all exceptions are
- * of the same \em ex_t C type).
- * - the variable of CATCH can naturally be reused in subsequent
- * CATCH clauses.
- * - it is possible to nest TRY clauses.
- *
- * The TRY block is a regular ISO-C language statement block, but it is not
- * allowed to jump into it via "goto" or longjmp(3) or out of it via "break",
- * "return", "goto" or longjmp(3) because there is some hidden setup and
- * cleanup that needs to be done regardless of whether an exception is
- * caught. Bypassing these steps will break the exception handling facility.
- *
- * The CLEANUP and CATCH blocks are regular ISO-C language statement
- * blocks without any restrictions. You are even allowed to throw (and, in the
- * CATCH block, to re-throw) exceptions.
- *
- * There is one subtle detail you should remember about TRY blocks:
- * Variables used in the CLEANUP or CATCH clauses must be declared with
- * the storage class "volatile", otherwise they might contain outdated
- * information if an exception it thrown.
- *
- *
- * This is because you usually do not know which commands in the TRY
- * were already successful before the exception was thrown (logically speaking)
- * and because the underlying ISO-C setjmp(3) facility applies those
- * restrictions (technically speaking). As a matter of fact, value changes
- * between the TRY and the THROW may be discarded if you forget the
- * "volatile" keyword.
- *
- * @section XBT_ex_advanced ADVANCED USAGE
- *
- * @subsection DEFER DEFERING_BLOCK XBT_ex_defer
- *
- * This directive executes DEFERING_BLOCK while deferring the throwing of
- * exceptions, i.e., exceptions thrown within this block are remembered, but
- * the control flow still continues until the end of the block. At its end, the
- * first exception which occured within the block (if any) is rethrown (any
- * subsequent exceptions are ignored).
- *
- * DEFERING_BLOCK is a regular ISO-C language statement block, but it is not
- * allowed to jump into it via "goto" or longjmp(3) or out of it via "break",
- * "return", "goto" or longjmp(3). It is however allowed to nest DEFER
- * clauses.
- *
- * @subsection XBT_ex_shield SHIELD SHIELDED_BLOCK
- *
- * This directive executes SHIELDED_BLOCK while shielding it against the
- * throwing of exceptions, i.e., any exception thrown from this block or its
- * subroutines are silently ignored.
- *
- * SHIELDED_BLOCK is a regular ISO-C language statement block, but it is not
- * allowed to jump into it via "goto" or longjmp(3) or out of it via "break",
- * "return", "goto" or longjmp(3). It is however allowed to nest SHIELD
- * clauses.
- *
- * @subsection XBT_ex_conditions Retrieving the current execution condition
- *
- * \a IS_CATCHED, \a IS_DEFERRED and \a IS_SHIELDED return a boolean
- * indicating whether the current scope is within a TRYIED_BLOCK,
- * DEFERING_BLOCK and SHIELDED_BLOCK (respectively)
- *
- * \section XBT_ex_pitfalls PROGRAMMING PITFALLS
- *
- * Exception handling is a very elegant and efficient way of dealing with
- * exceptional situation. Nevertheless it requires additional discipline in
- * programming and there are a few pitfalls one must be aware of. Look the
- * following code which shows some pitfalls and contains many errors (assuming
- * a mallocex() function which throws an exception if malloc(3) fails):
- *
- * \dontinclude ex_test.c
- * \skip BAD_EXAMPLE
- * \until end_of_bad_example
- *
- * This example raises a few issues:
- * -# \b variable \b scope \n
- * Variables which are used in the CLEANUP or CATCH clauses must be
- * declared before the TRY clause, otherwise they only exist inside the
- * TRY block. In the example above, cp1, cp2 and cp3 only exist in the
- * TRY block and are invisible from the CLEANUP and CATCH
- * blocks.
- * -# \b variable \b initialization \n
- * Variables which are used in the CLEANUP or CATCH clauses must
- * be initialized before the point of the first possible THROW is
- * reached. In the example above, CLEANUP would have trouble using cp3
- * if mallocex() throws a exception when allocating a TOOBIG buffer.
- * -# \b volatile \b variable \n
- * Variables which are used in the CLEANUP or CATCH clauses MUST BE
- * DECLARED AS "volatile", otherwise they might contain outdated
- * information when an exception is thrown.
- * -# \b clean \b before \b catch \n
- * The CLEANUP clause is not only place before the CATCH clause in
- * the source code, it also occures before in the control flow. So,
- * resources being cleaned up cannot be used in the CATCH block. In the
- * example, c3 gets freed before the printf placed in CATCH.
- * -# \b variable \b uninitialization \n
- * If resources are passed out of the scope of the
- * TRY/CLEANUP/CATCH construct, they naturally shouldn't get
- * cleaned up. The example above does free(3) cp1 in CLEANUP although
- * its value was affected to globalcontext->first, invalidating this
- * pointer.
+#include <xbt/base.h>
+#include <xbt/misc.h>
+#include <xbt/sysdep.h>
+#include <xbt/virtu.h>
- * The following is fixed version of the code (annotated with the pitfall items
- * for reference):
- *
- * \skip GOOD_EXAMPLE
- * \until end_of_good_example
+/** @addtogroup XBT_ex_c
+ * @brief Exceptions support (C)
*
- * @{
+ * Those functions are used to throw C++ exceptions from C code. This feature
+ * should probably be removed in the future because C and exception do not
+ * exactly play nicely together.
*/
-/** @brief Structure describing an exception */
-typedef struct {
- char *msg; /**< human readable message; to be freed */
- int category; /**< category like HTTP (what went wrong) */
- int value; /**< like errno (why did it went wrong) */
- /* throw point */
- char *host; /* NULL for localhost; hostname:port if remote */
- char *procname;
- char *file; /**< to be freed only for remote exceptions */
- int line;
- char *func; /**< to be freed only for remote exceptions */
-} ex_t;
-
-/* declare the context type (private) */
-typedef struct {
- __ex_mctx_t *ctx_mctx; /* permanent machine context of enclosing try/catch */
- int ctx_deferred; /* permanent flag whether exception is deferred */
- int ctx_deferring;/* permanent counter of exception deferring level */
- int ctx_defer; /* temporary flag for exception deferring macro */
- int ctx_shielding;/* permanent counter of exception shielding level */
- int ctx_shield; /* temporary flag for exception shielding macro */
- int ctx_caught; /* temporary flag whether exception was caught */
- volatile ex_t ctx_ex; /* temporary exception storage */
-} ex_ctx_t;
+SG_BEGIN_DECL
-/* the static and dynamic initializers for a context structure */
-#define XBT_CTX_INITIALIZER \
- { NULL, 0, 0, 0, 0, 0, 0, { /* content */ NULL, 0, 0, \
- /*throw point*/ NULL, NULL, NULL, 0, NULL } }
-#define XBT_CTX_INITIALIZE(ctx) \
- do { \
- (ctx)->ctx_mctx = NULL; \
- (ctx)->ctx_deferred = 0; \
- (ctx)->ctx_deferring = 0; \
- (ctx)->ctx_defer = 0; \
- (ctx)->ctx_shielding = 0; \
- (ctx)->ctx_shield = 0; \
- (ctx)->ctx_caught = 0; \
- (ctx)->ctx_ex.msg = NULL; \
- (ctx)->ctx_ex.category = 0; \
- (ctx)->ctx_ex.value = 0; \
- (ctx)->ctx_ex.host = NULL; \
- (ctx)->ctx_ex.procname = NULL; \
- (ctx)->ctx_ex.file = NULL; \
- (ctx)->ctx_ex.line = 0; \
- (ctx)->ctx_ex.func = NULL; \
- } while (0)
-
-/* the exception context */
-typedef ex_ctx_t *(*ex_ctx_cb_t)(void);
-extern ex_ctx_cb_t __xbt_ex_ctx;
-extern ex_ctx_t *__xbt_ex_ctx_default(void);
-
-/* the termination handler */
-typedef void (*ex_term_cb_t)(ex_t *);
-extern ex_term_cb_t __xbt_ex_terminate;
-extern void __xbt_ex_terminate_default(ex_t *e);
-
-/** @brief Introduce a block where exception may be dealed with
- * @hideinitializer
- */
-#define TRY \
- { \
- ex_ctx_t *__xbt_ex_ctx_ptr = __xbt_ex_ctx(); \
- int __ex_cleanup = 0; \
- __ex_mctx_t *__ex_mctx_en; \
- __ex_mctx_t __ex_mctx_me; \
- __ex_mctx_en = __xbt_ex_ctx_ptr->ctx_mctx; \
- __xbt_ex_ctx_ptr->ctx_mctx = &__ex_mctx_me; \
- if (__ex_mctx_save(&__ex_mctx_me)) { \
- if (1)
-
-/** @brief optional(!) block for cleanup
- * @hideinitializer
- */
-#define CLEANUP \
- else { \
- } \
- __xbt_ex_ctx_ptr->ctx_caught = 0; \
- } \
- else { \
- __ex_mctx_restored(&__ex_mctx_me); \
- __xbt_ex_ctx_ptr->ctx_caught = 1; \
- } \
- __xbt_ex_ctx_ptr->ctx_mctx = __ex_mctx_en; \
- __ex_cleanup = 1; \
- if (1) { \
- if (1)
+/** Helper function used to throw exceptions in C */
+XBT_ATTRIB_NORETURN XBT_PUBLIC void _xbt_throw(char* message, int value, const char* file, int line, const char* func);
-/** @brief the block for catching (ie, deal with) an exception
+/** Builds and throws an exception
+ * @ingroup XBT_ex_c
* @hideinitializer
*/
-#define CATCH(e) \
- else { \
- } \
- if (!(__ex_cleanup)) \
- __xbt_ex_ctx_ptr->ctx_caught = 0; \
- } \
- else { \
- if (!(__ex_cleanup)) { \
- __ex_mctx_restored(&__ex_mctx_me); \
- __xbt_ex_ctx_ptr->ctx_caught = 1; \
- } \
- } \
- __xbt_ex_ctx_ptr->ctx_mctx = __ex_mctx_en; \
- } \
- if ( !(__xbt_ex_ctx()->ctx_caught) \
- || ((e) = __xbt_ex_ctx()->ctx_ex, 0)) { \
- } \
- else
+#define THROW(v) _xbt_throw(NULL, (v), __FILE__, __LINE__, __func__)
-/** @brief Build an exception from the supplied arguments and throws it
+/** Builds and throws an exception with a printf-like formatted message
+ * @ingroup XBT_ex_c
* @hideinitializer
- *
- * @param c: category code (integer)
- * @param v: value (integer)
- * @param m: message text
- *
- * If called from within a sg_try/sg_catch construct, this exception
- * is copied into the sg_catch relevant variable program control flow
- * is derouted to the sg_catch (after the optional sg_cleanup).
- *
- * If no sg_try/sg_catch conctruct embeeds this call, the program calls
- * abort(3).
- *
- * The sg_throw can be performed everywhere, including inside sg_try,
- * sg_cleanup and sg_catch blocks.
*/
-#define THROW(c,v,m) \
- (( __xbt_ex_ctx()->ctx_shielding > 0 \
- || (__xbt_ex_ctx()->ctx_deferring > 0 && __xbt_ex_ctx()->ctx_deferred == 1)) ? 0 : \
- (__xbt_ex_ctx()->ctx_ex.msg = bprintf(m), \
- __xbt_ex_ctx()->ctx_ex.category = (c), \
- __xbt_ex_ctx()->ctx_ex.value = (v), \
- __xbt_ex_ctx()->ctx_ex.host = (char*)NULL, \
- __xbt_ex_ctx()->ctx_ex.procname = strdup(xbt_procname()), \
- __xbt_ex_ctx()->ctx_ex.file = (char*)__FILE__, \
- __xbt_ex_ctx()->ctx_ex.line = __LINE__, \
- __xbt_ex_ctx()->ctx_ex.func = (char*)_XBT_FUNCTION, \
- __xbt_ex_ctx()->ctx_deferred = 1, \
- (__xbt_ex_ctx()->ctx_deferring > 0 ? 0 : \
- (__xbt_ex_ctx()->ctx_mctx == NULL \
- ? (__xbt_ex_terminate((ex_t *)&(__xbt_ex_ctx()->ctx_ex)), -1) \
- : (__ex_mctx_restore(__xbt_ex_ctx()->ctx_mctx), 1) ))))
+#define THROWF(v, ...) _xbt_throw(bprintf(__VA_ARGS__), (v), __FILE__, __LINE__, __func__)
-/** @brief re-throwing of an already caught exception (ie, pass it to the upper catch block)
- * @hideinitializer
+XBT_ATTRIB_NORETURN void xbt_throw_impossible(const char* file, int line, const char* func);
+/** Throw an exception because something impossible happened
+ * @ingroup XBT_ex_c
*/
-#define RETHROW \
- (( __xbt_ex_ctx()->ctx_shielding > 0 \
- || __xbt_ex_ctx()->ctx_deferring > 0) ? 0 : \
- ( __xbt_ex_ctx()->ctx_mctx == NULL \
- ? (__xbt_ex_terminate((ex_t *)&(__xbt_ex_ctx()->ctx_ex)), -1) \
- : (__ex_mctx_restore(__xbt_ex_ctx()->ctx_mctx), 1) ))
+#define THROW_IMPOSSIBLE xbt_throw_impossible(__FILE__, __LINE__, __func__)
-/** @brief shield an operation from exception handling
- * @hideinitializer
+/** Throw an exception because something unimplemented stuff has been attempted
+ * @ingroup XBT_ex_c
*/
-#define SHIELD \
- for (__xbt_ex_ctx()->ctx_shielding++, \
- __xbt_ex_ctx()->ctx_shield = 1; \
- __xbt_ex_ctx()->ctx_shield == 1; \
- __xbt_ex_ctx()->ctx_shield = 0, \
- __xbt_ex_ctx()->ctx_shielding--)
+XBT_ATTRIB_NORETURN XBT_PUBLIC void xbt_throw_unimplemented(const char* file, int line, const char* func);
+#define THROW_UNIMPLEMENTED xbt_throw_unimplemented(__FILE__, __LINE__, __func__)
-/** @brief defer immediate exception handling
- * @hideinitializer
+/** Die because something impossible happened
+ * @ingroup XBT_ex_c
*/
-#define DEFER \
- for (((__xbt_ex_ctx()->ctx_deferring)++ == 0 ? __xbt_ex_ctx()->ctx_deferred = 0 : 0), \
- __xbt_ex_ctx()->ctx_defer = 1; \
- __xbt_ex_ctx()->ctx_defer == 1; \
- __xbt_ex_ctx()->ctx_defer = 0, \
- ((--(__xbt_ex_ctx()->ctx_deferring) == 0 && __xbt_ex_ctx()->ctx_deferred == 1) ? RETHROW : 0))
+#define DIE_IMPOSSIBLE xbt_die("The Impossible Did Happen (yet again)")
-/** @brief exception handling tests
- * @hideinitializer
- */
-#define IS_CATCHED \
- (__xbt_ex_ctx()->ctx_mctx != NULL)
-/** @brief exception handling tests
- * @hideinitializer
- */
-#define IS_SHIELDED \
- (__xbt_ex_ctx()->ctx_shielding > 0)
-/** @brief exception handling tests
- * @hideinitializer
- */
-#define IS_DEFERRED \
- (__xbt_ex_ctx()->ctx_deferring > 0)
+SG_END_DECL
-/** @} */
-#endif /* __XBT_EX_H__ */
-
+/** @} */
+#endif /* XBT_EX_H */
