altstack: Use ptrint instead of bare casts

Functions invoked with altstack take a void * parameter.  However, the
test program wants to pass an integer, and so uses the trick of casting
the integer values to (void *) and back again.

The ptrint() module handles exactly this case in a more portable and
(somewhat) typesafe way, so use that instead.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

ccan/altstack/_info

@@ -122,6 +122,11 @@ int main(int argc, char *argv[])
 	if (strcmp(argv[1], "depends") == 0)
 		return 0;
 
+	if (strcmp(argv[1], "testdepends") == 0) {
+		printf("ccan/ptrint\n");
+		return 0;
+	}
+
 	if (strcmp(argv[1], "ported") == 0) {
 #ifdef __x86_64__
 		printf("\n");

ccan/altstack/test/run.c

@@ -8,6 +8,7 @@
 #include <unistd.h>
 #include <sys/mman.h>
 #include <ccan/tap/tap.h>
+#include <ccan/ptrint/ptrint.h>
 #include <ccan/altstack/altstack.h>
 #include <stdio.h>
 
@@ -53,7 +54,7 @@ static void __attribute__((optimize("O0"))) dn(unsigned long i)
 }
 static void *wrap(void *i)
 {
-	dn((unsigned long) i);
+	dn(ptr2int(i));
 	return wrap;
 }
 
@@ -86,43 +87,43 @@ int main(void)
 
 	plan_tests(50);
 
-	chkfail(getrlimit_,	altstack(8*MiB, wrap, 0, 0) == -1, e(getrlimit_),
+	chkfail(getrlimit_,	altstack(8*MiB, wrap, int2ptr(0), 0) == -1, e(getrlimit_),
 		0,
 		0);
 
-	chkfail(setrlimit_,	altstack(8*MiB, wrap, 0, 0) == -1, e(setrlimit_),
+	chkfail(setrlimit_,	altstack(8*MiB, wrap, int2ptr(0), 0) == -1, e(setrlimit_),
 		getrlimit_,
 		0);
 
-	chkfail(mmap_,		altstack(8*MiB, wrap, 0, 0) == -1, e(mmap_),
+	chkfail(mmap_,		altstack(8*MiB, wrap, int2ptr(0), 0) == -1, e(mmap_),
 		getrlimit_|setrlimit_,
 		setrlimit_);
 
-	chkfail(sigaltstack_,	altstack(8*MiB, wrap, 0, 0) == -1, e(sigaltstack_),
+	chkfail(sigaltstack_,	altstack(8*MiB, wrap, int2ptr(0), 0) == -1, e(sigaltstack_),
 		getrlimit_|setrlimit_|mmap_,
 		setrlimit_|munmap_);
 
-	chkfail(sigaction_,	altstack(8*MiB, wrap, 0, 0) == -1, e(sigaction_),
+	chkfail(sigaction_,	altstack(8*MiB, wrap, int2ptr(0), 0) == -1, e(sigaction_),
 		getrlimit_|setrlimit_|mmap_|sigaltstack_,
 		setrlimit_|munmap_|sigaltstack_);
 
-	chkfail(munmap_,	altstack(8*MiB, wrap, 0, 0) ==  1, e(munmap_),
+	chkfail(munmap_,	altstack(8*MiB, wrap, int2ptr(0), 0) ==  1, e(munmap_),
 		getrlimit_|setrlimit_|mmap_|sigaltstack_|sigaction_,
 		setrlimit_|sigaltstack_|sigaction_);
 	if (fail = 0, munmap(m_, msz_) == -1)
 		err(1, "munmap");
 
-	chkok(			altstack(1*MiB, wrap, (void *) 1000000, 0) == -1, EOVERFLOW,
+	chkok(			altstack(1*MiB, wrap, int2ptr(1000000), 0) == -1, EOVERFLOW,
 		getrlimit_|setrlimit_|mmap_|sigaltstack_|sigaction_,
 		setrlimit_|munmap_|sigaltstack_|sigaction_);
 
 	// be sure segv catch is repeatable (SA_NODEFER)
-	chkok(			altstack(1*MiB, wrap, (void *) 1000000, 0) == -1, EOVERFLOW,
+	chkok(			altstack(1*MiB, wrap, int2ptr(1000000), 0) == -1, EOVERFLOW,
 		getrlimit_|setrlimit_|mmap_|sigaltstack_|sigaction_,
 		setrlimit_|munmap_|sigaltstack_|sigaction_);
 
 	used = 1;
-	chkfail(munmap_,	altstack(1*MiB, wrap, (void *) 1000000, 0) == -1, EOVERFLOW,
+	chkfail(munmap_,	altstack(1*MiB, wrap, int2ptr(1000000), 0) == -1, EOVERFLOW,
 		getrlimit_|setrlimit_|mmap_|sigaltstack_|sigaction_,
 		setrlimit_|sigaltstack_|sigaction_);
 	if (fail = 0, munmap(m_, msz_) == -1)
@@ -149,7 +150,7 @@ int main(void)
 	ok1(strcmp(buf, estr "\n") == 0);
 
 	used = 1;
-	chkok(			altstack(8*MiB, wrap, (void *) 1000000, 0) == -1, EOVERFLOW,
+	chkok(			altstack(8*MiB, wrap, int2ptr(1000000), 0) == -1, EOVERFLOW,
 		getrlimit_|setrlimit_|mmap_|sigaltstack_|sigaction_,
 		setrlimit_|munmap_|sigaltstack_|sigaction_);
 
@@ -157,7 +158,7 @@ int main(void)
 	ok1(used >= 8*MiB - pgsz && used <= 8*MiB + pgsz);
 
 	used = 0;
-	chkok(			altstack(8*MiB, wrap, (void *) 100000, 0) == 0, 0,
+	chkok(			altstack(8*MiB, wrap, int2ptr(100000), 0) == 0, 0,
 		getrlimit_|setrlimit_|mmap_|sigaltstack_|sigaction_|munmap_,
 		setrlimit_|munmap_|sigaltstack_|sigaction_);