err: Add err(), warn(), errx() and warnx() familiy of functions

Some systems such as Windows or musl-libc based ones do not have these
BSD extensions. In addition libbsd itself is making use of the warnx()
functions, so we better provide these interfaces in case they are
missing.

1 files changed, 24 insertions, 0 deletions

diff --git a/include/bsd/err.h b/include/bsd/err.h
index 9e83260..adf08f6 100644
--- a/include/bsd/err.h
+++ b/include/bsd/err.h
@@ -29,11 +29,15 @@
 #include <sys/cdefs.h>
 #if __has_include_next(<err.h>)
 #include_next <err.h>
+#else
+#define LIBBSD_NEED_ERR_H_FUNCS
 #endif
 #else
 #include <bsd/sys/cdefs.h>
 #if __has_include(<err.h>)
 #include <err.h>
+#else
+#define LIBBSD_NEED_ERR_H_FUNCS
 #endif
 #endif
 
@@ -52,6 +56,26 @@ void verrc(int status, int code, const char *format, va_list ap)
 	__printflike(3, 0) __dead2;
 void errc(int status, int code, const char *format, ...)
 	__printflike(3, 4) __dead2;
+
+#ifdef LIBBSD_NEED_ERR_H_FUNCS
+void vwarn(const char *format, va_list ap)
+	__printflike(1, 0);
+void vwarnx(const char *format, va_list ap)
+	__printflike(1, 0);
+void warn(const char *format, ...)
+	__printflike(1, 2);
+void warnx(const char *format, ...)
+	__printflike(1, 2);
+
+void verr(int status, const char *format, va_list ap)
+	__printflike(2, 0) __dead2;
+void verrx(int status, const char *format, va_list ap)
+	__printflike(2, 0) __dead2;
+void err(int status, const char *format, ...)
+	__printflike(2, 3) __dead2;
+void errx(int status, const char *format, ...)
+	__printflike(2, 3) __dead2;
+#endif
 __END_DECLS
 
 #endif