nightmaremail

commit 105e01c5cbdd7f042043f595794f12ff8664dda3
parent edf54c818e5549026098acd95ae44f0ddf6a7722
Author: Rolf Eike Beer <eike@sf-mail.de>
Date:   Sun, 10 May 2020 15:28:09 +0200

add compat version of __builtin_{add,mul}_overflow()

Diffstat:
M
Makefile
 | 
23
+++++++++++++++--------
M
TARGETS
 | 
1
+
A
chkbiofl.c
 | 
5
+++++
A
oflops_bi.h
 | 
6
++++++
A
oflops_compat.h
 | 
27
+++++++++++++++++++++++++++

5 files changed, 54 insertions(+), 8 deletions(-)
diff --git a/Makefile b/Makefile
@@ -772,7 +772,7 @@ compile ip.c fmt.h scan.h ip.h
 
 ipalloc.o: \
 compile ipalloc.c alloc.h gen_allocdefs.h ip.h ipalloc.h ip.h \
-gen_alloc.h
+gen_alloc.h oflops.h
 	./compile ipalloc.c
 
 ipme.o: \
@@ -954,6 +954,13 @@ now.o: \
 compile now.c datetime.h now.h datetime.h
 	./compile now.c
 
+oflops.h: \
+chkbiofl.c compile load oflops_bi.h oflops_compat.h
+	 ( ( ./compile chkbiofl.c  && ./load chkbiofl && \
+	./chkbiofl ) >/dev/null 2>&1 \
+	&& cat oflops_bi.h || cat oflops_compat.h ) > oflops.h
+	rm -f chkbiofl.o chkbiofl
+
 open.a: \
 makelib open_append.o open_excl.o open_read.o open_trunc.o \
 open_write.o
@@ -1020,7 +1027,7 @@ substdio.h exit.h fork.h wait.h env.h sig.h error.h
 
 prioq.o: \
 compile prioq.c alloc.h gen_allocdefs.h prioq.h datetime.h \
-gen_alloc.h
+gen_alloc.h oflops.h
 	./compile prioq.c
 
 proc: \
@@ -1139,7 +1146,7 @@ compile qmail-inject.c sig.h substdio.h stralloc.h gen_alloc.h \
 subfd.h substdio.h sgetopt.h subgetopt.h getln.h alloc.h str.h fmt.h \
 hfield.h token822.h gen_alloc.h control.h env.h gen_alloc.h \
 gen_allocdefs.h error.h qmail.h substdio.h now.h datetime.h exit.h \
-quote.h headerbody.h auto_qmail.h newfield.h stralloc.h constmap.h
+quote.h headerbody.h auto_qmail.h newfield.h stralloc.h constmap.h oflops.h
 	./compile qmail-inject.c
 
 qmail-limits.0: \
@@ -1428,7 +1435,7 @@ compile qmail-remote.c sig.h stralloc.h gen_alloc.h substdio.h \
 subfd.h substdio.h scan.h case.h error.h auto_qmail.h control.h dns.h \
 alloc.h quote.h ip.h ipalloc.h ip.h gen_alloc.h ipme.h ip.h ipalloc.h \
 gen_alloc.h gen_allocdefs.h str.h now.h datetime.h exit.h constmap.h \
-tcpto.h readwrite.h timeoutconn.h timeoutread.h timeoutwrite.h
+tcpto.h readwrite.h timeoutconn.h timeoutread.h timeoutwrite.h oflops.h
 	./compile qmail-remote.c
 
 qmail-rspawn: \
@@ -1624,7 +1631,7 @@ qreceipt.o: \
 compile qreceipt.c sig.h env.h substdio.h stralloc.h gen_alloc.h \
 subfd.h substdio.h getln.h alloc.h str.h hfield.h token822.h \
 gen_alloc.h error.h gen_alloc.h gen_allocdefs.h headerbody.h exit.h \
-open.h quote.h qmail.h substdio.h
+open.h quote.h qmail.h substdio.h oflops.h
 	./compile qreceipt.c
 
 qsmhook: \
@@ -1876,7 +1883,7 @@ compile stralloc_copy.c byte.h stralloc.h gen_alloc.h
 
 stralloc_eady.o: \
 compile stralloc_eady.c alloc.h stralloc.h gen_alloc.h \
-gen_allocdefs.h
+gen_allocdefs.h oflops.h
 	./compile stralloc_eady.c
 
 stralloc_opyb.o: \
@@ -1889,7 +1896,7 @@ compile stralloc_opys.c byte.h str.h stralloc.h gen_alloc.h
 
 stralloc_pend.o: \
 compile stralloc_pend.c alloc.h stralloc.h gen_alloc.h \
-gen_allocdefs.h
+gen_allocdefs.h oflops.h
 	./compile stralloc_pend.c
 
 strerr.a: \
@@ -2005,7 +2012,7 @@ compile timeoutwrite.c timeoutwrite.h select.h error.h readwrite.h
 
 token822.o: \
 compile token822.c stralloc.h gen_alloc.h alloc.h str.h token822.h \
-gen_alloc.h gen_allocdefs.h
+gen_alloc.h gen_allocdefs.h oflops.h
 	./compile token822.c
 
 trigger.o: \
diff --git a/TARGETS b/TARGETS
@@ -25,6 +25,7 @@ subgetopt.o
 sgetopt.o
 getopt.a
 sig_alarm.o
+oflops.h
 hassgprm.h
 sig_block.o
 hassgact.h
diff --git a/chkbiofl.c b/chkbiofl.c
@@ -0,0 +1,5 @@
+int main()
+{
+ unsigned int a = 0x80000000, b = 0x80000000, c;
+ return !__builtin_add_overflow(a, b, &c) && !__builtin_mul_overflow(a, b, &c);
+}
diff --git a/oflops_bi.h b/oflops_bi.h
@@ -0,0 +1,6 @@
+#ifndef OFLOPS_H
+#define OFLOPS_H
+
+/* this header is intentionally empty, compiler builtins are used. */
+
+#endif /* OFLOPS_H */
diff --git a/oflops_compat.h b/oflops_compat.h
@@ -0,0 +1,27 @@
+#ifndef OFLOPS_H
+#define OFLOPS_H
+
+static inline int check_ofl(unsigned long long val, unsigned int *res)
+{
+	if (val >> 32)
+		return 1;
+	*res = (unsigned int)val;
+	return 0;
+}
+
+static inline int __builtin_add_overflow(unsigned int a, unsigned int b, unsigned int *res)
+{
+	unsigned long long val = a;
+	val += b;
+	return check_ofl(val, res);
+}
+
+static inline int __builtin_mul_overflow(unsigned int a, unsigned int b, unsigned int *res)
+{
+	unsigned long long val = a;
+	val *= b;
+	return check_ofl(val, res);
+}
+
+#endif /* OFLOPS_H */
+