created aux::typed_span and related refactor

include/libtorrent/Makefile.am

@@ -196,6 +196,7 @@ nobase_include_HEADERS = \
   aux_/numeric_cast.hpp             \
   aux_/unique_ptr.hpp               \
   aux_/alloca.hpp                   \
+  aux_/typed_span.hpp               \
   \
   extensions/smart_ban.hpp          \
   extensions/ut_metadata.hpp        \

include/libtorrent/aux_/alloca.hpp

@@ -33,32 +33,32 @@ POSSIBILITY OF SUCH DAMAGE.
 #ifndef TORRENT_ALLOCA
 
 #include "libtorrent/config.hpp"
-#include "libtorrent/span.hpp"
+#include "libtorrent/aux_/typed_span.hpp"
 #include "libtorrent/aux_/numeric_cast.hpp"
 
 #if defined TORRENT_WINDOWS || defined TORRENT_MINGW
 
 #include <malloc.h>
-#define TORRENT_ALLOCA(v, t, n) ::libtorrent::span<t> v; { \
+#define TORRENT_ALLOCA(v, t, n) ::libtorrent::aux::typed_span<t> v; { \
 	std::size_t TORRENT_ALLOCA_size = ::libtorrent::aux::numeric_cast<std::size_t>(n); \
 	t* TORRENT_ALLOCA_tmp = static_cast<t*>(_alloca(sizeof(t) * TORRENT_ALLOCA_size)); \
-	v = ::libtorrent::span<t>(TORRENT_ALLOCA_tmp, TORRENT_ALLOCA_size); }
+	v = ::libtorrent::aux::typed_span<t>(TORRENT_ALLOCA_tmp, TORRENT_ALLOCA_size); }
 
 #elif defined TORRENT_BSD
 
 #include <stdlib.h>
-#define TORRENT_ALLOCA(v, t, n) ::libtorrent::span<t> v; { \
+#define TORRENT_ALLOCA(v, t, n) ::libtorrent::aux::typed_span<t> v; { \
 	std::size_t TORRENT_ALLOCA_size = ::libtorrent::aux::numeric_cast<std::size_t>(n); \
 	t* TORRENT_ALLOCA_tmp = static_cast<t*>(alloca(sizeof(t) * TORRENT_ALLOCA_size)); \
-	v = ::libtorrent::span<t>(TORRENT_ALLOCA_tmp, TORRENT_ALLOCA_size); }
+	v = ::libtorrent::aux::typed_span<t>(TORRENT_ALLOCA_tmp, TORRENT_ALLOCA_size); }
 
 #else
 
 #include <alloca.h>
-#define TORRENT_ALLOCA(v, t, n) ::libtorrent::span<t> v; { \
+#define TORRENT_ALLOCA(v, t, n) ::libtorrent::aux::typed_span<t> v; { \
 	std::size_t TORRENT_ALLOCA_size = ::libtorrent::aux::numeric_cast<std::size_t>(n); \
 	t* TORRENT_ALLOCA_tmp = static_cast<t*>(alloca(sizeof(t) * TORRENT_ALLOCA_size)); \
-	v = ::libtorrent::span<t>(TORRENT_ALLOCA_tmp, TORRENT_ALLOCA_size); }
+	v = ::libtorrent::aux::typed_span<t>(TORRENT_ALLOCA_tmp, TORRENT_ALLOCA_size); }
 
 #endif
 

include/libtorrent/aux_/typed_span.hpp

@@ -0,0 +1,126 @@
+/*
+
+Copyright (c) 2017, Arvid Norberg, Alden Torres
+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.
+    * Neither the name of the author nor the names of its
+      contributors may be used to endorse or promote products derived
+      from this software without specific prior written permission.
+
+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 TORRENT_TYPED_SPAN_HPP
+#define TORRENT_TYPED_SPAN_HPP
+
+#include <type_traits>
+
+#include "libtorrent/units.hpp"
+#include "libtorrent/span.hpp"
+#include "libtorrent/assert.hpp"
+
+namespace libtorrent { namespace aux {
+
+	template <typename T, typename IndexType = int>
+	struct typed_span : span<T>
+	{
+		using base = span<T>;
+		using underlying_index = typename underlying_index_t<IndexType>::type;
+
+		// pull in constructors from base class
+		using base::base;
+
+		auto operator[](IndexType idx) -> decltype(this->base::operator[](underlying_index()))
+		{
+			TORRENT_ASSERT(idx >= IndexType(0));
+			return this->base::operator[](std::size_t(static_cast<underlying_index>(idx)));
+		}
+
+		IndexType end_index() const
+		{
+			TORRENT_ASSERT(this->size() <= std::size_t(std::numeric_limits<underlying_index>::max()));
+			return IndexType(static_cast<underlying_index>(this->size()));
+		}
+
+		template <typename U = underlying_index, typename Cond
+			= typename std::enable_if<std::is_signed<U>::value>::type>
+		typed_span<T> first(underlying_index n)
+		{
+			TORRENT_ASSERT(n >= 0);
+			return this->base::first(std::size_t(n));
+		}
+
+		typed_span<T> first(std::size_t n)
+		{
+			TORRENT_ASSERT(n <= std::size_t((std::numeric_limits<underlying_index>::max)()));
+			return this->base::first(n);
+		}
+
+		template <typename U = underlying_index, typename Cond
+			= typename std::enable_if<std::is_signed<U>::value>::type>
+		typed_span<T> last(underlying_index n)
+		{
+			TORRENT_ASSERT(n >= 0);
+			return this->base::last(std::size_t(n));
+		}
+
+		typed_span<T> last(std::size_t n)
+		{
+			TORRENT_ASSERT(n <= std::size_t((std::numeric_limits<underlying_index>::max)()));
+			return this->base::last(n);
+		}
+
+		template <typename U = underlying_index, typename Cond
+			= typename std::enable_if<std::is_signed<U>::value>::type>
+		typed_span<T> subspan(underlying_index offset)
+		{
+			TORRENT_ASSERT(offset >= 0);
+			return this->base::subspan(std::size_t(offset));
+		}
+
+		template <typename U = underlying_index, typename Cond
+			= typename std::enable_if<std::is_signed<U>::value>::type>
+		typed_span<T> subspan(underlying_index offset, underlying_index count)
+		{
+			TORRENT_ASSERT(offset >= 0);
+			TORRENT_ASSERT(count >= 0);
+			return this->base::subspan(std::size_t(offset), std::size_t(count));
+		}
+
+		typed_span<T> subspan(std::size_t offset)
+		{
+			TORRENT_ASSERT(offset <= std::size_t((std::numeric_limits<underlying_index>::max)()));
+			return this->base::subspan(offset);
+		}
+
+		typed_span<T> subspan(std::size_t offset, std::size_t count)
+		{
+			TORRENT_ASSERT(offset <= std::size_t((std::numeric_limits<underlying_index>::max)()));
+			TORRENT_ASSERT(count <= std::size_t((std::numeric_limits<underlying_index>::max)()));
+			return this->base::subspan(offset, count);
+		}
+	};
+
+}}
+
+#endif

include/libtorrent/aux_/unique_ptr.hpp

@@ -51,7 +51,7 @@ namespace libtorrent { namespace aux {
 		using underlying_index = typename underlying_index_t<IndexType>::type;
 
 		unique_ptr() {}
-		explicit unique_ptr(T arr[]) : base(arr) {}
+		explicit unique_ptr(T* arr) : base(arr) {}
 
 		auto operator[](IndexType idx) const -> decltype(this->base::operator[](underlying_index()))
 		{

src/bdecode.cpp

@@ -653,7 +653,7 @@ namespace libtorrent
 
 		// this is the stack of bdecode_token indices, into m_tokens.
 		// sp is the stack pointer, as index into the array, stack
-		std::size_t sp = 0;
+		int sp = 0;
 		TORRENT_ALLOCA(stack, stack_frame, depth_limit);
 
 		char const* const orig_start = start;
@@ -665,7 +665,7 @@ namespace libtorrent
 		{
 			if (start >= end) TORRENT_FAIL_BDECODE(bdecode_errors::unexpected_eof);
 
-			if (sp >= aux::numeric_cast<std::size_t>(depth_limit))
+			if (sp >= depth_limit)
 				TORRENT_FAIL_BDECODE(bdecode_errors::depth_exceeded);
 
 			--token_limit;
@@ -675,7 +675,7 @@ namespace libtorrent
 			// look for a new token
 			char const t = *start;
 
-			std::size_t const current_frame = sp;
+			int const current_frame = sp;
 
 			// if we're currently parsing a dictionary, assert that
 			// every other node is a string.

src/block_cache.cpp

@@ -554,7 +554,7 @@ void block_cache::try_evict_one_volatile()
 		// some blocks are pinned in this piece, skip it
 		if (pe->pinned > 0) continue;
 
-		TORRENT_ALLOCA(to_delete, char*, std::size_t(pe->blocks_in_piece));
+		TORRENT_ALLOCA(to_delete, char*, pe->blocks_in_piece);
 		int num_to_delete = 0;
 
 		// go through the blocks and evict the ones that are not dirty and not
@@ -861,7 +861,7 @@ bool block_cache::evict_piece(cached_piece_entry* pe, tailqueue<disk_io_job>& jo
 
 	TORRENT_PIECE_ASSERT(pe->in_use, pe);
 
-	TORRENT_ALLOCA(to_delete, char*, std::size_t(pe->blocks_in_piece));
+	TORRENT_ALLOCA(to_delete, char*, pe->blocks_in_piece);
 	int num_to_delete = 0;
 	for (int i = 0; i < pe->blocks_in_piece; ++i)
 	{
@@ -1393,7 +1393,7 @@ void block_cache::abort_dirty(cached_piece_entry* pe)
 
 	TORRENT_PIECE_ASSERT(pe->in_use, pe);
 
-	TORRENT_ALLOCA(to_delete, char*, std::size_t(pe->blocks_in_piece));
+	TORRENT_ALLOCA(to_delete, char*, pe->blocks_in_piece);
 	int num_to_delete = 0;
 	for (int i = 0; i < pe->blocks_in_piece; ++i)
 	{
@@ -1432,7 +1432,7 @@ void block_cache::free_piece(cached_piece_entry* pe)
 
 	// build a vector of all the buffers we need to free
 	// and free them all in one go
-	TORRENT_ALLOCA(to_delete, char*, std::size_t(pe->blocks_in_piece));
+	TORRENT_ALLOCA(to_delete, char*, pe->blocks_in_piece);
 	int num_to_delete = 0;
 	int removed_clean = 0;
 	for (int i = 0; i < pe->blocks_in_piece; ++i)

src/disk_io_thread.cpp

@@ -762,8 +762,8 @@ namespace libtorrent
 		TORRENT_PIECE_ASSERT(start >= 0, pe);
 		TORRENT_PIECE_ASSERT(start < end, pe);
 
-		TORRENT_ALLOCA(iov, iovec_t, std::size_t(pe->blocks_in_piece));
-		TORRENT_ALLOCA(flushing, int, std::size_t(pe->blocks_in_piece));
+		TORRENT_ALLOCA(iov, iovec_t, pe->blocks_in_piece);
+		TORRENT_ALLOCA(flushing, int, pe->blocks_in_piece);
 		int iov_len = build_iovec(pe, start, end, iov, flushing, 0);
 		if (iov_len == 0) return 0;