Port: Add Solaris fls compat

[lttng-tools.git] / src / common / compat / string.h

diff --git a/src/common/compat/string.h b/src/common/compat/string.h
index 91a1c09e2f1df86bff864da0235ba5a9989b5a1b..7c426ef3de3bd97e5056ef469f6db6cb528b1c61 100644 (file)
--- a/src/common/compat/string.h
+++ b/src/common/compat/string.h
@@ -1,5 +1,6 @@
 /*
  * Copyright (C) 2015 Michael Jeanson <mjeanson@efficios.com>
+ *               2015 Jérémie Galarneau <jeremie.galarneau@efficios.com>
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -86,4 +87,41 @@ end:
 }
 #endif /* HAVE_STRNDUP */
 
+#ifdef HAVE_FLS
+static inline int lttng_fls(int val)
+{
+       return fls(val);
+}
+#else
+static inline int lttng_fls(int val)
+{
+       int r = 32;
+       unsigned int x = (unsigned int) val;
+
+       if (!x)
+               return 0;
+       if (!(x & 0xFFFF0000U)) {
+               x <<= 16;
+               r -= 16;
+       }
+       if (!(x & 0xFF000000U)) {
+               x <<= 8;
+               r -= 8;
+       }
+       if (!(x & 0xF0000000U)) {
+               x <<= 4;
+               r -= 4;
+       }
+       if (!(x & 0xC0000000U)) {
+               x <<= 2;
+               r -= 2;
+       }
+       if (!(x & 0x80000000U)) {
+               x <<= 1;
+               r -= 1;
+       }
+       return r;
+}
+#endif /* HAVE_FLS */
+
 #endif /* _COMPAT_STRING_H */