1 /* GSysExceptions.c low level module interfacing exceptions to the OS.
2
3 Copyright (C) 2016-2023 Free Software Foundation, Inc.
4 Contributed by Gaius Mulley <gaius@glam.ac.uk>.
5
6 This file is part of GNU Modula-2.
7
8 GNU Modula-2 is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 3, or (at your option)
11 any later version.
12
13 GNU Modula-2 is distributed in the hope that it will be useful, but
14 WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 General Public License for more details.
17
18 You should have received a copy of the GNU General Public License
19 along with GNU Modula-2; see the file COPYING3. If not see
20 <http://www.gnu.org/licenses/>. */
21
22 #include "config.h"
23 #include "system.h"
24
25 #include "gm2-libs-host.h"
26
27 #if defined(__cplusplus)
28 #define EXTERN extern "C"
29 #else
30 #define EXTERN
31 #endif
32
33 #if 0
34 /* Signals. */
35 #define SIGHUP 1 /* Hangup (POSIX). */
36 #define SIGINT 2 /* Interrupt (ANSI). */
37 #define SIGQUIT 3 /* Quit (POSIX). */
38 #define SIGILL 4 /* Illegal instruction (ANSI). */
39 #define SIGTRAP 5 /* Trace trap (POSIX). */
40 #define SIGABRT 6 /* Abort (ANSI). */
41 #define SIGIOT 6 /* IOT trap (4.2 BSD). */
42 #define SIGBUS 7 /* BUS error (4.2 BSD). */
43 #define SIGFPE 8 /* Floating-point exception (ANSI). */
44 #define SIGKILL 9 /* Kill, unblockable (POSIX). */
45 #define SIGUSR1 10 /* User-defined signal 1 (POSIX). */
46 #define SIGSEGV 11 /* Segmentation violation (ANSI). */
47 #define SIGUSR2 12 /* User-defined signal 2 (POSIX). */
48 #define SIGPIPE 13 /* Broken pipe (POSIX). */
49 #define SIGALRM 14 /* Alarm clock (POSIX). */
50 #define SIGTERM 15 /* Termination (ANSI). */
51 #define SIGSTKFLT 16 /* Stack fault. */
52 #define SIGCLD SIGCHLD /* Same as SIGCHLD (System V). */
53 #define SIGCHLD 17 /* Child status has changed (POSIX). */
54 #define SIGCONT 18 /* Continue (POSIX). */
55 #define SIGSTOP 19 /* Stop, unblockable (POSIX). */
56 #define SIGTSTP 20 /* Keyboard stop (POSIX). */
57 #define SIGTTIN 21 /* Background read from tty (POSIX). */
58 #define SIGTTOU 22 /* Background write to tty (POSIX). */
59 #define SIGURG 23 /* Urgent condition on socket (4.2 BSD). */
60 #define SIGXCPU 24 /* CPU limit exceeded (4.2 BSD). */
61 #define SIGXFSZ 25 /* File size limit exceeded (4.2 BSD). */
62 #define SIGVTALRM 26 /* Virtual alarm clock (4.2 BSD). */
63 #define SIGPROF 27 /* Profiling alarm clock (4.2 BSD). */
64 #define SIGWINCH 28 /* Window size change (4.3 BSD, Sun). */
65 #define SIGPOLL SIGIO /* Pollable event occurred (System V). */
66 #define SIGIO 29 /* I/O now possible (4.2 BSD). */
67 #define SIGPWR 30 /* Power failure restart (System V). */
68 #define SIGSYS 31 /* Bad system call. */
69 #define SIGUNUSED 31
70
71
72 (indexException, rangeException, caseSelectException, invalidLocation,
73 functionException, wholeValueException, wholeDivException, realValueException,
74 realDivException, complexValueException, complexDivException, protException,
75 sysException, coException, exException
76 );
77
78 #endif
79
80 /* wholeDivException and realDivException are caught by SIGFPE
81 and depatched to the appropriate Modula-2 runtime routine upon
82 testing FPE_INTDIV or FPE_FLTDIV. realValueException is also
83 caught by SIGFPE and dispatched by testing FFE_FLTOVF or
84 FPE_FLTUND or FPE_FLTRES or FPE_FLTINV. indexException is
85 caught by SIGFPE and dispatched by FPE_FLTSUB. */
86
87 #if defined(HAVE_SIGNAL_H)
88 static struct sigaction sigbus;
89 static struct sigaction sigfpe_;
90 static struct sigaction sigsegv;
91
92 static void (*indexProc) (void *);
93 static void (*rangeProc) (void *);
94 static void (*assignmentrangeProc) (void *);
95 static void (*caseProc) (void *);
96 static void (*invalidlocProc) (void *);
97 static void (*functionProc) (void *);
98 static void (*wholevalueProc) (void *);
99 static void (*wholedivProc) (void *);
100 static void (*realvalueProc) (void *);
101 static void (*realdivProc) (void *);
102 static void (*complexvalueProc) (void *);
103 static void (*complexdivProc) (void *);
104 static void (*protectionProc) (void *);
105 static void (*systemProc) (void *);
106 static void (*coroutineProc) (void *);
107 static void (*exceptionProc) (void *);
108
109 static void
110 sigbusDespatcher (int signum, siginfo_t *info, void *ucontext)
111 {
112 switch (signum)
113 {
114
115 case SIGSEGV:
116 case SIGBUS:
117 if (info)
118 (*invalidlocProc) (info->si_addr);
119 break;
120 default:
121 perror ("not expecting to arrive here with this signal");
122 }
123 }
124
125 static void
126 sigfpeDespatcher (int signum, siginfo_t *info, void *ucontext)
127 {
128 switch (signum)
129 {
130
131 case SIGFPE:
132 if (info)
133 {
134 if (info->si_code | FPE_INTDIV)
135 (*wholedivProc) (info->si_addr); /* integer divide by zero. */
136 if (info->si_code | FPE_INTOVF)
137 (*wholevalueProc) (info->si_addr); /* integer overflow. */
138 if (info->si_code | FPE_FLTDIV)
139 (*realdivProc) (
140 info->si_addr); /* floating-point divide by zero. */
141 if (info->si_code | FPE_FLTOVF)
142 (*realvalueProc) (info->si_addr); /* floating-point overflow. */
143 if (info->si_code | FPE_FLTUND)
144 (*realvalueProc) (info->si_addr); /* floating-point underflow. */
145 if (info->si_code | FPE_FLTRES)
146 (*realvalueProc) (
147 info->si_addr); /* floating-point inexact result. */
148 if (info->si_code | FPE_FLTINV)
149 (*realvalueProc) (
150 info->si_addr); /* floating-point invalid result. */
151 if (info->si_code | FPE_FLTSUB)
152 (*indexProc) (info->si_addr); /* subscript out of range. */
153 }
154 break;
155 default:
156 perror ("not expecting to arrive here with this signal");
157 }
158 }
159
160 EXTERN
161 void
162 SysExceptions_InitExceptionHandlers (
163 void (*indexf) (void *), void (*range) (void *), void (*casef) (void *),
164 void (*invalidloc) (void *), void (*function) (void *),
165 void (*wholevalue) (void *), void (*wholediv) (void *),
166 void (*realvalue) (void *), void (*realdiv) (void *),
167 void (*complexvalue) (void *), void (*complexdiv) (void *),
168 void (*protection) (void *), void (*systemf) (void *),
169 void (*coroutine) (void *), void (*exception) (void *))
170 {
171 struct sigaction old;
172
173 indexProc = indexf;
174 rangeProc = range;
175 caseProc = casef;
176 invalidlocProc = invalidloc;
177 functionProc = function;
178 wholevalueProc = wholevalue;
179 wholedivProc = wholediv;
180 realvalueProc = realvalue;
181 realdivProc = realdiv;
182 complexvalueProc = complexvalue;
183 complexdivProc = complexdiv;
184 protectionProc = protection;
185 systemProc = systemf;
186 coroutineProc = coroutine;
187 exceptionProc = exception;
188
189 sigbus.sa_sigaction = sigbusDespatcher;
190 sigbus.sa_flags = (SA_SIGINFO);
191 sigemptyset (&sigbus.sa_mask);
192
193 if (sigaction (SIGBUS, &sigbus, &old) != 0)
194 perror ("unable to install the sigbus signal handler");
195
196 sigsegv.sa_sigaction = sigbusDespatcher;
197 sigsegv.sa_flags = (SA_SIGINFO);
198 sigemptyset (&sigsegv.sa_mask);
199
200 if (sigaction (SIGSEGV, &sigsegv, &old) != 0)
201 perror ("unable to install the sigsegv signal handler");
202
203 sigfpe_.sa_sigaction = sigfpeDespatcher;
204 sigfpe_.sa_flags = (SA_SIGINFO);
205 sigemptyset (&sigfpe_.sa_mask);
206
207 if (sigaction (SIGFPE, &sigfpe_, &old) != 0)
208 perror ("unable to install the sigfpe signal handler");
209 }
210
211 #else
212 EXTERN
213 void
214 SysExceptions_InitExceptionHandlers (void *indexf, void *range, void *casef,
215 void *invalidloc, void *function,
216 void *wholevalue, void *wholediv,
217 void *realvalue, void *realdiv,
218 void *complexvalue, void *complexdiv,
219 void *protection, void *systemf,
220 void *coroutine, void *exception)
221 {
222 }
223 #endif
224
225 /* GNU Modula-2 linking fodder. */
226
227 EXTERN
228 void
229 _M2_SysExceptions_init (int argc, char *argv[], char *envp[])
230 {
231 }
232
233 EXTERN
234 void
235 _M2_SysExceptions_fini (int argc, char *argv[], char *envp[])
236 {
237 }