-/*
-** 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) 2005-2022. 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)
-
-#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)
-
-#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 Introduction
- *
- * 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 Basic usage
- *
- * \em xbt_try \b TRIED_BLOCK [\em xbt_cleanup \b CLEANUP_BLOCK] \em xbt_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:
- * - xbt_try, xbt_cleanup and xbt_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 xbt_catch block and not multiple ones (all exceptions are
- * of the same C type xbt_t).
- * - the variable of xbt_catch can naturally be reused in subsequent
- * xbt_catch clauses.
- * - it is possible to nest xbt_try clauses.
- *
- * The xbt_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 xbt_cleanup and xbt_catch blocks are regular ISO-C language statement
- * blocks without any restrictions. You are even allowed to throw (and in the
- * xbt_catch block to re-throw) exceptions.
- *
- * There is one subtle detail you should remember about xbt_try blocks:
- * Variables used in the xbt_cleanup or xbt_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 xbt_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 xbt_try and the xbt_throw may be discarded if you forget the
- * "volatile" keyword.
- *
- * @section Advanced usage
- *
- * @subsection xbt_defer DEFERING_BLOCK
- *
- * 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 xbt_defer
- * clauses.
- *
- * @subsection xbt_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 xbt_shield
- * clauses.
- *
- * @subsection Retrieving the current execution condition
- *
- * \a xbt_catching, \a xbt_deferred and \a xbt_shielding return a boolean
- * indicating whether the current scope is within a TRYIED_BLOCK,
- * DEFERING_BLOCK and SHIELDED_BLOCK (respectively)
- *
- * \section 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):
- *
- \verbatim
-// BAD EXAMPLE
-xbt_try {
- char *cp1, *cp2, cp3;
+#ifndef XBT_EX_H
+#define XBT_EX_H
- cp1 = mallocex(SMALLAMOUNT);
- globalcontext->first = cp1;
- cp2 = mallocex(TOOBIG);
- cp3 = mallocex(SMALLAMOUNT);
- strcpy(cp1, "foo");
- strcpy(cp2, "bar");
-} xbt_cleanup {
- if (cp3 != NULL) free(cp3);
- if (cp2 != NULL) free(cp2);
- if (cp1 != NULL) free(cp1);
-} xbt_catch(ex) {
- printf("cp3=%s", cp3);
- ex_rethrow;
-}\endverbatim
+#include <stdlib.h>
- * This example raises a few issues:
- * -# \b variable scope\n
- * Variables which are used in the xbt_cleanup or xbt_catch clauses must be
- * declared before the xbt_try clause, otherwise they only exist inside the
- * xbt_try block. In the example above, cp1, cp2 and cp3 only exist in the
- * xbt_try block and are invisible from the xbt_cleanup and xbt_catch
- * blocks.
- * -# \b variable initialization \n
- * Variables which are used in the xbt_cleanup or xbt_catch clauses must
- * be initialized before the point of the first possible xbt_throw is
- * reached. In the example above, xbt_cleanup would have trouble using cp3
- * if mallocex() throws a exception when allocating a TOOBIG buffer.
- * -# \b volatile variable \n
- * Variables which are used in the xbt_cleanup or xbt_catch clauses MUST BE
- * DECLARED AS "volatile", otherwise they might contain outdated
- * information when an exception is thrown.
- * -# \b clean before catch \n
- * The xbt_cleanup clause is not only place before the xbt_catch clause in
- * the source code, it also occures before in the control flow. So,
- * resources being cleaned up cannot be used in the xbt_catch block. In the
- * example, c3 gets freed before the printf placed in xbt_catch.
- * -# \b variable uninitialization \n
- * If resources are passed out of the scope of the
- * xbt_try/xbt_cleanup/xbt_catch construct, they naturally shouldn't get
- * cleaned up. The example above does free(3) cp1 in xbt_cleanup although
- * its value was affected to globalcontext->first, invalidating this
- * pointer.
-
- * The following is fixed version of the code (annotated with the pitfall items
- * for reference):
- \verbatim
-// GOOD EXAMPLE
-{ / *01* /
- char * volatile / *03* / cp1 = NULL / *02* /;
- char * volatile / *03* / cp2 = NULL / *02* /;
- char * volatile / *03* / cp3 = NULL / *02* /;
- try {
- cp1 = mallocex(SMALLAMOUNT);
- globalcontext->first = cp1;
- cp1 = NULL / *05 give away* /;
- cp2 = mallocex(TOOBIG);
- cp3 = mallocex(SMALLAMOUNT);
- strcpy(cp1, "foo");
- strcpy(cp2, "bar");
- }
- clean { / *04* /
- printf("cp3=%s", cp3 == NULL / *02* / ? "" : cp3);
- if (cp3 != NULL)
- free(cp3);
- if (cp2 != NULL)
- free(cp2);
- / *05 cp1 was given away * /
- }
- catch(ex) {
- / *05 global context untouched * /
- rethrow;
- }
-}\endverbatim
+#include <xbt/base.h>
+#include <xbt/misc.h>
+#include <xbt/sysdep.h>
+#include <xbt/virtu.h>
+/** @addtogroup XBT_ex_c
+ * @brief Exceptions support (C)
*
- * @{
- */
-
-/** @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;
-
-/* 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 xbt_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
+ * 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.
*/
-#define xbt_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)
-/** @brief the block for catching (ie, deal with) an exception
- * @hideinitializer
- */
-#define xbt_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
+SG_BEGIN_DECL
-/** @brief Build an exception from the supplied arguments and throws it
- * @hideinitializer
- *
- * 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 xbt_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) ))))
+/** Helper function used to throw exceptions in C */
+XBT_ATTRIB_NORETURN XBT_PUBLIC void _xbt_throw(char* message, const char* file, int line, const char* func);
-/** @brief re-throwing of an already caught exception (ie, pass it to the upper catch block)
+/** Builds and throws an exception with a printf-like formatted message
+ * @ingroup XBT_ex_c
* @hideinitializer
*/
-#define xbt_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(...) _xbt_throw(bprintf(__VA_ARGS__), __FILE__, __LINE__, __func__)
-/** @brief shield an operation from exception handling
- * @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 xbt_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--)
+#define THROW_IMPOSSIBLE xbt_throw_impossible(__FILE__, __LINE__, __func__)
-/** @brief defer immediate exception handling
- * @hideinitializer
+/** Throw an exception because something unimplemented stuff has been attempted
+ * @ingroup XBT_ex_c
*/
-#define xbt_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) ? xbt_rethrow : 0))
+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 exception handling tests
- * @hideinitializer
- */
-#define xbt_catching \
- (__xbt_ex_ctx()->ctx_mctx != NULL)
-/** @brief exception handling tests
- * @hideinitializer
- */
-#define xbt_shielding \
- (__xbt_ex_ctx()->ctx_shielding > 0)
-/** @brief exception handling tests
- * @hideinitializer
+/** Die because something impossible happened
+ * @ingroup XBT_ex_c
*/
-#define xbt_deferring \
- (__xbt_ex_ctx()->ctx_deferring > 0)
+#define DIE_IMPOSSIBLE xbt_die("The Impossible Did Happen (yet again)")
-/* optional namespace mapping */
-#if defined(__EX_NS_UCCXX__)
-#define Try xbt_try
-#define Cleanup xbt_cleanup
-#define Catch xbt_catch
-#define Throw xbt_throw
-#define Rethrow xbt_rethrow
-#define Shield xbt_shield
-#define Defer xbt_defer
-#elif defined(__EX_NS_CXX__) || (!defined(__cplusplus) && !defined(__EX_NS_CUSTOM__))
-#define try xbt_try
-#define cleanup xbt_cleanup
-#define catch xbt_catch
-#define throw xbt_throw
-#define rethrow xbt_rethrow
-#define shield xbt_shield
-#define defer xbt_defer
-#endif
+SG_END_DECL
-/** @} */
-#endif /* __XBT_EX_H__ */
-
+/** @} */
+#endif /* XBT_EX_H */