src: major cleanups, introduce new eXtended Span class

- initial minimally invasive eXtended Span implementation - rename ptr_diff to ptr_diff_bytes - move some files to util subdir - lots of cleanups - start using the new checked pointers - this needs some real-world testing
2022-09-11 16:03:56 +02:00
parent 4318cc22ee
commit c75d7a685d
54 changed files with 3521 additions and 1196 deletions
@@ -0,0 +1,135 @@
+/* xspan -- a minimally invasive checked memory smart pointer
+
+   This file is part of the UPX executable compressor.
+
+   Copyright (C) 1996-2022 Markus Franz Xaver Johannes Oberhumer
+   All Rights Reserved.
+
+   UPX and the UCL library are free software; you can redistribute them
+   and/or modify them under the terms of the GNU General Public License as
+   published by the Free Software Foundation; either version 2 of
+   the License, or (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; see the file COPYING.
+   If not, write to the Free Software Foundation, Inc.,
+   59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+
+   Markus F.X.J. Oberhumer
+   <markus@oberhumer.com>
+ */
+
+#pragma once
+
+SPAN_NAMESPACE_BEGIN
+
+/*************************************************************************
+// Span
+//
+// invariants:
+//   ptr != null, base != null
+//   ptr is valid in base
+**************************************************************************/
+
+template <class T>
+struct Span {
+private:
+#define CSelf Span
+    typedef CSelf<T> Self;
+    // core config
+    enum { configRequirePtr = true };
+    enum { configRequireBase = true };
+
+#include "xspan_impl_common.h"
+public:
+    // constructors from pointers
+    CSelf(pointer first) SPAN_DELETED_FUNCTION;
+
+    // constructors
+    CSelf(const Self &other)
+        : ptr(other.ensurePtr()), base(other.ensureBase()), size_in_bytes(other.size_in_bytes) {}
+    template <class U>
+    CSelf(const CSelf<U> &other, SPAN_REQUIRES_CONVERTIBLE_A)
+        : ptr(other.ensurePtr()), base(other.ensureBase()), size_in_bytes(other.size_in_bytes) {}
+
+    // constructors from Span friends
+#if SPAN_CONFIG_ENABLE_SPAN_CONVERSION
+    template <class U>
+    CSelf(const PtrOrSpanOrNull<U> &other, SPAN_REQUIRES_CONVERTIBLE_A)
+        : ptr(other.ensurePtr()), base(other.ensureBase()), size_in_bytes(other.size_in_bytes) {}
+    template <class U>
+    CSelf(const PtrOrSpan<U> &other, SPAN_REQUIRES_CONVERTIBLE_A)
+        : ptr(other.ensurePtr()), base(other.ensureBase()), size_in_bytes(other.size_in_bytes) {}
+#endif
+
+    // assignment from Span friends
+#if SPAN_CONFIG_ENABLE_SPAN_CONVERSION
+    // TODO: use Unchecked to avoid double checks in both constructor and assignment
+    template <class U>
+    SPAN_REQUIRES_CONVERTIBLE_R(Self &)
+    operator=(const PtrOrSpan<U> &other) {
+        if (other.base == nullptr)
+            return assign(Self(other.ptr, size_in_bytes, base));
+        return assign(Self(other.ptr, other.size_in_bytes, other.base));
+    }
+    template <class U>
+    SPAN_REQUIRES_CONVERTIBLE_R(Self &)
+    operator=(const PtrOrSpanOrNull<U> &other) {
+        if (other.base == nullptr)
+            return assign(Self(other.ptr, size_in_bytes, base));
+        return assign(Self(other.ptr, other.size_in_bytes, other.base));
+    }
+#endif
+
+    // nullptr
+    CSelf(std::nullptr_t) SPAN_DELETED_FUNCTION;
+    CSelf(std::nullptr_t, SpanSizeInBytes, const void *) SPAN_DELETED_FUNCTION;
+    CSelf(std::nullptr_t, SpanCount, const void *) SPAN_DELETED_FUNCTION;
+    CSelf(std::nullptr_t, size_type, const void *) SPAN_DELETED_FUNCTION;
+    Self &operator=(std::nullptr_t) SPAN_DELETED_FUNCTION;
+#if 0
+    // don't enable, this prevents generic usage
+    bool operator==(std::nullptr_t) const SPAN_DELETED_FUNCTION;
+    bool operator!=(std::nullptr_t) const SPAN_DELETED_FUNCTION;
+#else
+    bool operator==(std::nullptr_t) const {
+        assertInvariants();
+        return false;
+    }
+    bool operator!=(std::nullptr_t) const {
+        assertInvariants();
+        return true;
+    }
+#endif
+#undef CSelf
+};
+
+template <class T>
+inline T *raw_bytes(const Span<T> &a, size_t size_in_bytes) {
+    return a.raw_bytes(size_in_bytes);
+}
+
+/*************************************************************************
+//
+**************************************************************************/
+
+SPAN_NAMESPACE_END
+
+#if !SPAN_CONFIG_ENABLE_IMPLICIT_CONVERSION || 1
+
+#define C SPAN_NS(Span)
+#define D SPAN_NS(PtrOrSpanOrNull)
+#define E SPAN_NS(PtrOrSpan)
+#include "xspan_fwd.h"
+#undef C
+#undef D
+#undef E
+
+#endif
+
+/* vim:set ts=4 sw=4 et: */