1 /****************************************************************************
3 * GNAT COMPILER COMPONENTS *
7 * C Implementation File *
9 * Copyright (C) 2005, Free Software Foundation, Inc. *
11 * GNAT is free software; you can redistribute it and/or modify it under *
12 * terms of the GNU General Public License as published by the Free Soft- *
13 * ware Foundation; either version 2, or (at your option) any later ver- *
14 * sion. GNAT is distributed in the hope that it will be useful, but WITH- *
15 * OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY *
16 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License *
17 * for more details. You should have received a copy of the GNU General *
18 * Public License distributed with GNAT; see file COPYING. If not, write *
19 * to the Free Software Foundation, 51 Franklin Street, Fifth Floor, *
20 * Boston, MA 02110-1301, USA. *
22 * As a special exception, if you link this file with other files to *
23 * produce an executable, this file does not by itself cause the resulting *
24 * executable to be covered by the GNU General Public License. This except- *
25 * ion does not however invalidate any other reasons why the executable *
26 * file might be covered by the GNU Public License. *
28 * GNAT was originally developed by the GNAT team at New York University. *
29 * Extensive contributions were provided by Ada Core Technologies Inc. *
31 ****************************************************************************/
33 /* This unit contains support for SEH (Structured Exception Handling).
34 Right now the only implementation is for Win32. */
40 /* We don't have libiberty, so us malloc. */
41 #define xmalloc(S) malloc (S)
50 /* Addresses of exception data blocks for predefined exceptions. */
51 extern struct Exception_Data constraint_error;
52 extern struct Exception_Data numeric_error;
53 extern struct Exception_Data program_error;
54 extern struct Exception_Data storage_error;
55 extern struct Exception_Data tasking_error;
56 extern struct Exception_Data _abort_signal;
58 #define Raise_From_Signal_Handler \
59 ada__exceptions__raise_from_signal_handler
60 extern void Raise_From_Signal_Handler (struct Exception_Data *, const char *);
68 extern void _global_unwind2 (void *);
70 EXCEPTION_DISPOSITION __gnat_SEH_error_handler
71 (struct _EXCEPTION_RECORD*, void*, struct _CONTEXT*, void*);
74 __gnat_SEH_error_handler (struct _EXCEPTION_RECORD* ExceptionRecord,
75 void *EstablisherFrame,
76 struct _CONTEXT* ContextRecord ATTRIBUTE_UNUSED,
77 void *DispatcherContext ATTRIBUTE_UNUSED)
79 struct Exception_Data *exception;
82 switch (ExceptionRecord->ExceptionCode)
84 case EXCEPTION_ACCESS_VIOLATION:
85 /* If the failing address isn't maximally-aligned or if the page
86 before the faulting page is not accessible, this is a program error.
88 if ((ExceptionRecord->ExceptionInformation[1] & 3) != 0
90 ((void *)(ExceptionRecord->ExceptionInformation[1] + 4096)))
92 exception = &program_error;
93 msg = "EXCEPTION_ACCESS_VIOLATION";
97 /* otherwise it is a stack overflow */
98 exception = &storage_error;
99 msg = "stack overflow (or erroneous memory access)";
103 case EXCEPTION_ARRAY_BOUNDS_EXCEEDED:
104 exception = &constraint_error;
105 msg = "EXCEPTION_ARRAY_BOUNDS_EXCEEDED";
108 case EXCEPTION_DATATYPE_MISALIGNMENT:
109 exception = &constraint_error;
110 msg = "EXCEPTION_DATATYPE_MISALIGNMENT";
113 case EXCEPTION_FLT_DENORMAL_OPERAND:
114 exception = &constraint_error;
115 msg = "EXCEPTION_FLT_DENORMAL_OPERAND";
118 case EXCEPTION_FLT_DIVIDE_BY_ZERO:
119 exception = &constraint_error;
120 msg = "EXCEPTION_FLT_DENORMAL_OPERAND";
123 case EXCEPTION_FLT_INVALID_OPERATION:
124 exception = &constraint_error;
125 msg = "EXCEPTION_FLT_INVALID_OPERATION";
128 case EXCEPTION_FLT_OVERFLOW:
129 exception = &constraint_error;
130 msg = "EXCEPTION_FLT_OVERFLOW";
133 case EXCEPTION_FLT_STACK_CHECK:
134 exception = &program_error;
135 msg = "EXCEPTION_FLT_STACK_CHECK";
138 case EXCEPTION_FLT_UNDERFLOW:
139 exception = &constraint_error;
140 msg = "EXCEPTION_FLT_UNDERFLOW";
143 case EXCEPTION_INT_DIVIDE_BY_ZERO:
144 exception = &constraint_error;
145 msg = "EXCEPTION_INT_DIVIDE_BY_ZERO";
148 case EXCEPTION_INT_OVERFLOW:
149 exception = &constraint_error;
150 msg = "EXCEPTION_INT_OVERFLOW";
153 case EXCEPTION_INVALID_DISPOSITION:
154 exception = &program_error;
155 msg = "EXCEPTION_INVALID_DISPOSITION";
158 case EXCEPTION_NONCONTINUABLE_EXCEPTION:
159 exception = &program_error;
160 msg = "EXCEPTION_NONCONTINUABLE_EXCEPTION";
163 case EXCEPTION_PRIV_INSTRUCTION:
164 exception = &program_error;
165 msg = "EXCEPTION_PRIV_INSTRUCTION";
168 case EXCEPTION_SINGLE_STEP:
169 exception = &program_error;
170 msg = "EXCEPTION_SINGLE_STEP";
173 case EXCEPTION_STACK_OVERFLOW:
174 exception = &storage_error;
175 msg = "EXCEPTION_STACK_OVERFLOW";
179 exception = &program_error;
180 msg = "unhandled signal";
183 /* This call is important as it avoids locking the second time we catch a
184 signal. Note that this routine is documented as internal to Windows and
185 should not be used. */
187 _global_unwind2 (EstablisherFrame);
188 /* Call equivalent to RtlUnwind (EstablisherFrame, NULL, NULL, 0); */
190 Raise_From_Signal_Handler (exception, msg);
191 return 0; /* This is never reached, avoid compiler warning */
194 /* Install the Win32 SEH exception handler. Note that the caller must have
195 allocated 8 bytes on the stack and pass the pointer to this stack
196 space. This is needed as the SEH exception handler must be on the stack of
201 __gnat_install_SEH_handler ((void*)buf);
205 This call must be done before calling the main procedure or the thread
206 entry. The stack space must exists during all the main run. */
209 __gnat_install_SEH_handler (void *ER)
213 /* put current handler in ptr */
215 asm ("mov %%fs:(0),%%ecx" : : : "%ecx");
216 asm ("mov %%ecx,%0" : "=m" (ptr));
218 ((int *)ER)[0] = (int)ptr; /* previous handler */
219 ((int *)ER)[1] = (int)__gnat_SEH_error_handler; /* new handler */
221 /* ptr is the new handler, set fs:(0) with this value */
224 asm ("mov %0,%%ecx" : : "m" (ptr) : "%ecx");
225 asm ("mov %ecx,%fs:(0)");
229 /* For all non Windows targets we provide a dummy SEH install handler. */
230 void __gnat_install_SEH_handler (void *eh ATTRIBUTE_UNUSED)