New fpos class for the stream position.

2 files changed, 137 insertions, 0 deletions

diff --git a/include/ios_pos_types.h b/include/ios_pos_types.h
new file mode 100644
index 0000000..a096536
--- /dev/null
+++ b/include/ios_pos_types.h
@@ -0,0 +1,84 @@
+/* -*- c++ -*- */
+/*
+ * Copyright (C) 2010 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *  * Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  * Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#ifndef ANDROID_ASTL_IOS_POS_TYPES__
+#define ANDROID_ASTL_IOS_POS_TYPES__
+
+#include <cstddef>  // ptrdiff_t
+namespace std {
+
+// Type use by fpos.
+typedef long long streamoff;
+
+// Signed type for I/O operation counts and buffer sizes.
+typedef ptrdiff_t  streamsize;
+
+// In the regular STL fpos is a template which gets specialized for
+// char and wchar and defines 2 types streampos and wstreampos. Since
+// we don't support wchar, we just provide the final char compliant
+// version.  The methods to get/set the mbstate in fpos are not
+// provided.
+
+class fpos {
+  public:
+    fpos() : mOffs(0) { }
+    fpos(streamoff offs) : mOffs(offs) { }
+
+    // Convert to streamoff.
+    operator streamoff() const { return mOffs; }
+
+    // Not supported:
+    // void state(mbstate_t);
+    // mbstate_t state() const;
+
+    fpos& operator+=(streamoff offs);
+    fpos& operator-=(streamoff offs) {
+        return operator+=(-offs);
+    }
+
+    fpos operator+(streamoff offs) const;
+    fpos operator-(streamoff offs) const;
+
+  private:
+    streamoff mOffs;
+};
+
+inline bool
+operator==(const fpos& lhs, const fpos& rhs)
+{ return streamoff(lhs) == streamoff(rhs); }
+
+inline bool
+operator!=(const fpos& lhs, const fpos& rhs)
+{ return streamoff(lhs) != streamoff(rhs); }
+
+typedef fpos streampos;
+
+}  // namespace std
+
+#endif
diff --git a/include/limits b/include/limits
index 74ef1e0..f097c23 100644
--- a/include/limits
+++ b/include/limits
@@ -30,6 +30,7 @@
 #ifndef ANDROID_ASTL_LIMITS__
 #define ANDROID_ASTL_LIMITS__
 
+#include <limits.h>
 // GNU C++ compiler?
 #ifndef __GNUG__
 #error "__GNUG__ is not defined"
@@ -42,6 +43,26 @@
 // This is very incomplete partial implementation of the standard
 // <limits>. Only partial support for float and double is provided.
 
+namespace {
+// Template to return the number of decimal digits in a number
+// representation based on the number of bits and sign.
+// e.g  digits10<int,64,true>::value == 19
+template<typename T, T bits, bool is_signed> struct digits10 {
+    static const int value = 0;
+};
+
+// Specialization that can be used to initialize static constant at
+// compile time.
+template<> struct digits10<int,  8, false> { static const int value = 3; };
+template<> struct digits10<int,  8, true>  { static const int value = 3; };
+template<> struct digits10<int, 16, false> { static const int value = 5; };
+template<> struct digits10<int, 16, true>  { static const int value = 5; };
+template<> struct digits10<int, 32, false> { static const int value = 10; };
+template<> struct digits10<int, 32, true>  { static const int value = 10; };
+template<> struct digits10<int, 64, false> { static const int value = 20; };
+template<> struct digits10<int, 64, true>  { static const int value = 19; };
+}
+
 namespace std {
 
 struct __numeric_limits_base
@@ -113,6 +134,38 @@ struct numeric_limits<double>
     static const int digits10 = __DBL_DIG__;
 };
 
+// numeric_limits<long>
+template<>
+struct numeric_limits<long>
+{
+    static const bool is_specialized = true;
+
+    static long min() { return LONG_MIN; }
+    static long max() { return LONG_MAX; }
+
+    static const bool is_signed = true;
+    static const bool is_integer = true;
+
+    static const int digits = LONG_BIT;
+    static const int digits10 = digits10<int, digits, is_signed>::value;
+};
+
+// numeric_limits<long long>
+template<>
+struct numeric_limits<long long>
+{
+    static const bool is_specialized = true;
+
+    static long long min() { return LLONG_MIN; }
+    static long long max() { return LLONG_MAX; }
+
+    static const bool is_signed = true;
+    static const bool is_integer = true;
+
+    static const int digits = ((int)(sizeof(long long) * CHAR_BIT));
+    static const int digits10 = digits10<int, digits, is_signed>::value;
+};
+
 }  // namespace std