[hackers] [sic] add support for pledge()

[Joerg Jung]

Hi,

please find below a diff for sic to enable pledge() to be used on
OpenBSD.  This diff was originally submitted by Ali H. Fardan via
po...@openbsd.org.  While here, I enabled the usage of strlcpy()
from libc on OpenBSD. 

Honestly, I'm not sure about how such portability goo should be 
handled the suckless way, but since I see similar #ifdef __linux__
instances in slock, I guess the proposed way is okay?

Thanks,
Regards,
Joerg


diff --git a/sic.c b/sic.c
index ce6d216..b22ea06 100644
--- a/sic.c
+++ b/sic.c
@@ -182,6 +182,8 @@ main(int argc, char *argv[]) {
        setbuf(stdout, NULL);
        setbuf(srv, NULL);
        setbuf(stdin, NULL);
+       if (pledge("stdio", NULL) == -1)
+               eprint("error: pledge:");
        for(;;) { /* main loop */
                FD_ZERO(&rd);
                FD_SET(0, &rd);
diff --git a/util.c b/util.c
index 8afa58f..88ea06e 100644
--- a/util.c
+++ b/util.c
@@ -40,12 +40,16 @@ dial(char *host, char *port) {
        return srv;
 }
 
+#ifndef __OpenBSD__
+#define pledge(promises, paths) 0
+
 #define strlcpy _strlcpy
 static void
 strlcpy(char *to, const char *from, int l) {
        memccpy(to, from, '\0', l);
        to[l-1] = '\0';
 }
+#endif
 
 static char *
 eat(char *s, int (*p)(int), int r) {