add shared code in common.c

1 files changed, 20 insertions, 0 deletions

diff --git a/common.c b/common.c
new file mode 100644
index 0000000..b177987
--- /dev/null
+++ b/common.c
@@ -0,0 +1,20 @@
+#include "config.h"
+#include <stdarg.h>
+#include <strings.h>
+#include <unistd.h>
+
+// wrapper for write
+void writef(char *format, ...)
+{
+    va_list args;
+    char buf[BUF_MAX + 1];
+    va_start(args, format);
+
+    vsnprintf(buf, sizeof(buf), format, args);
+    va_end(args);
+
+    int n = 0;
+    while (*(buf + n) != 0)
+        n++;
+    write(0, buf, n);
+}