Add files for swift over UDP.

[swifty.git] / src / libswift_udp / bin.cpp

diff --git a/src/libswift_udp/bin.cpp b/src/libswift_udp/bin.cpp
new file mode 100644 (file)
index 0000000..1878f3e
--- /dev/null
+++ b/src/libswift_udp/bin.cpp
@@ -0,0 +1,169 @@
+/*
+ *  bin.cpp
+ *  swift
+ *
+ *  Created by Victor Grishchenko on 10/10/09.
+ *  Reimplemented by Alexander G. Pronchenkov on 05/05/10
+ *
+ *  Copyright 2010 Delft University of Technology. All rights reserved.
+ *
+ */
+
+#include "bin.h"
+#include <ostream>
+
+
+const bin_t bin_t::NONE(8 * sizeof(bin_t::uint_t), 0);
+const bin_t bin_t::ALL(8 * sizeof(bin_t::uint_t) - 1, 0);
+
+
+/* Methods */
+
+/**
+ * Gets the layer value of a bin
+ */
+int bin_t::layer(void) const
+{
+    if (is_none()) {
+        return -1;
+    }
+
+    int r = 0;
+
+#ifdef _MSC_VER
+#  pragma warning (push)
+#  pragma warning (disable:4146)
+#endif
+    register uint_t tail;
+    tail = v_ + 1;
+    tail = tail & (-tail);
+#ifdef _MSC_VER
+#  pragma warning (pop)
+#endif
+
+    if (tail > 0x80000000U) {
+        r = 32;
+        tail >>= 16;    // FIXME: hide warning
+        tail >>= 16;
+    }
+
+    // courtesy of Sean Eron Anderson
+    // http://graphics.stanford.edu/~seander/bithacks.html
+    static const char DeBRUIJN[32] = { 0, 1, 28, 2, 29, 14, 24, 3, 30, 22, 20, 15, 25, 17, 4, 8, 31, 27, 13, 23, 21, 19, 16, 7, 26, 12, 18, 6, 11, 5, 10, 9 };
+
+    return r + DeBRUIJN[ 0x1f & ((tail * 0x077CB531U) >> 27) ];
+}
+
+/* String operations */
+
+namespace {
+
+char* append(char* buf, int x)
+{
+    char* l = buf;
+    char* r = buf;
+
+    if (x < 0) {
+        *r++ = '-';
+        x = -x;
+    }
+
+    do {
+        *r++ = '0' + x % 10;
+        x /= 10;
+    } while (x);
+
+    char* e = r--;
+
+    while (l < r) {
+        const char t = *l;
+        *l++ = *r;
+        *r-- = t;
+    }
+
+    *e = '\0';
+
+    return e;
+}
+
+char* append(char* buf, bin_t::uint_t x)
+{
+    char* l = buf;
+    char* r = buf;
+
+    do {
+        *r++ = '0' + x % 10;
+        x /= 10;
+    } while (x);
+
+    char* e = r--;
+
+    while (l < r) {
+        const char t = *l;
+        *l++ = *r;
+        *r-- = t;
+    }
+
+    *e = '\0';
+
+    return e;
+}
+
+char* append(char* buf, const char* s)
+{
+    char* e = buf;
+
+    while (*s) {
+        *e++ = *s++;
+    }
+
+    *e = '\0';
+
+    return e;
+}
+
+char* append(char* buf, char c)
+{
+    char* e = buf;
+
+    *e++ = c;
+    *e = '\0';
+
+    return e;
+}
+
+} /* namespace */
+
+
+/**
+ * Get the standard-form of this bin, e.g. "(2,1)".
+ * (buffer should have enough of space)
+ */
+const char* bin_t::str(char* buf) const
+{
+    char* e = buf;
+
+    if (is_all()) {
+        e = append(e, "(ALL)");
+    } else if (is_none()) {
+        e = append(e, "(NONE)");
+    } else {
+        e = append(e, '(');
+        e = append(e, layer());
+        e = append(e, ',');
+        e = append(e, layer_offset());
+        e = append(e, ')');
+    }
+
+    return buf;
+}
+
+
+/**
+ * Output operator
+ */
+std::ostream & operator << (std::ostream & ostream, const bin_t & bin)
+{
+    char bin_name_buf[64];
+    return ostream << bin.str(bin_name_buf);
+}