Update common_audio
Corresponds to upstream commit 524e9b043e7e86fd72353b987c9d5f6a1ebf83e1 Update notes: * Moved src/ to webrtc/ to easily diff against the third_party/webrtc in the chromium tree * ARM/NEON/MIPS support is not yet hooked up * Tests have not been copied
This commit is contained in:
227
webrtc/base/checks.h
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227
webrtc/base/checks.h
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@ -0,0 +1,227 @@
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/*
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* Copyright 2006 The WebRTC Project Authors. All rights reserved.
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*
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* Use of this source code is governed by a BSD-style license
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* that can be found in the LICENSE file in the root of the source
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* tree. An additional intellectual property rights grant can be found
|
||||
* in the file PATENTS. All contributing project authors may
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* be found in the AUTHORS file in the root of the source tree.
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*/
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#ifndef WEBRTC_BASE_CHECKS_H_
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#define WEBRTC_BASE_CHECKS_H_
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#include <sstream>
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#include <string>
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#include "webrtc/typedefs.h"
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// The macros here print a message to stderr and abort under various
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// conditions. All will accept additional stream messages. For example:
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// RTC_DCHECK_EQ(foo, bar) << "I'm printed when foo != bar.";
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//
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// - RTC_CHECK(x) is an assertion that x is always true, and that if it isn't,
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// it's better to terminate the process than to continue. During development,
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// the reason that it's better to terminate might simply be that the error
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// handling code isn't in place yet; in production, the reason might be that
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// the author of the code truly believes that x will always be true, but that
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// she recognizes that if she is wrong, abrupt and unpleasant process
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// termination is still better than carrying on with the assumption violated.
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//
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// RTC_CHECK always evaluates its argument, so it's OK for x to have side
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// effects.
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//
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// - RTC_DCHECK(x) is the same as RTC_CHECK(x)---an assertion that x is always
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// true---except that x will only be evaluated in debug builds; in production
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// builds, x is simply assumed to be true. This is useful if evaluating x is
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// expensive and the expected cost of failing to detect the violated
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// assumption is acceptable. You should not handle cases where a production
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// build fails to spot a violated condition, even those that would result in
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// crashes. If the code needs to cope with the error, make it cope, but don't
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// call RTC_DCHECK; if the condition really can't occur, but you'd sleep
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// better at night knowing that the process will suicide instead of carrying
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// on in case you were wrong, use RTC_CHECK instead of RTC_DCHECK.
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//
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// RTC_DCHECK only evaluates its argument in debug builds, so if x has visible
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// side effects, you need to write e.g.
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// bool w = x; RTC_DCHECK(w);
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//
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// - RTC_CHECK_EQ, _NE, _GT, ..., and RTC_DCHECK_EQ, _NE, _GT, ... are
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// specialized variants of RTC_CHECK and RTC_DCHECK that print prettier
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// messages if the condition doesn't hold. Prefer them to raw RTC_CHECK and
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// RTC_DCHECK.
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//
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// - FATAL() aborts unconditionally.
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//
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// TODO(ajm): Ideally, checks.h would be combined with logging.h, but
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// consolidation with system_wrappers/logging.h should happen first.
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namespace rtc {
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// Helper macro which avoids evaluating the arguments to a stream if
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// the condition doesn't hold.
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#define RTC_LAZY_STREAM(stream, condition) \
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!(condition) ? static_cast<void>(0) : rtc::FatalMessageVoidify() & (stream)
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// The actual stream used isn't important. We reference condition in the code
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// but don't evaluate it; this is to avoid "unused variable" warnings (we do so
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// in a particularly convoluted way with an extra ?: because that appears to be
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// the simplest construct that keeps Visual Studio from complaining about
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// condition being unused).
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#define RTC_EAT_STREAM_PARAMETERS(condition) \
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(true ? true : !(condition)) \
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? static_cast<void>(0) \
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: rtc::FatalMessageVoidify() & rtc::FatalMessage("", 0).stream()
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// RTC_CHECK dies with a fatal error if condition is not true. It is *not*
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// controlled by NDEBUG, so the check will be executed regardless of
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// compilation mode.
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//
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// We make sure RTC_CHECK et al. always evaluates their arguments, as
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// doing RTC_CHECK(FunctionWithSideEffect()) is a common idiom.
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#define RTC_CHECK(condition) \
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RTC_LAZY_STREAM(rtc::FatalMessage(__FILE__, __LINE__).stream(), \
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!(condition)) \
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<< "Check failed: " #condition << std::endl << "# "
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// Helper macro for binary operators.
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// Don't use this macro directly in your code, use RTC_CHECK_EQ et al below.
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//
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// TODO(akalin): Rewrite this so that constructs like if (...)
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// RTC_CHECK_EQ(...) else { ... } work properly.
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#define RTC_CHECK_OP(name, op, val1, val2) \
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if (std::string* _result = \
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rtc::Check##name##Impl((val1), (val2), #val1 " " #op " " #val2)) \
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rtc::FatalMessage(__FILE__, __LINE__, _result).stream()
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// Build the error message string. This is separate from the "Impl"
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// function template because it is not performance critical and so can
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// be out of line, while the "Impl" code should be inline. Caller
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// takes ownership of the returned string.
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template<class t1, class t2>
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std::string* MakeCheckOpString(const t1& v1, const t2& v2, const char* names) {
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std::ostringstream ss;
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ss << names << " (" << v1 << " vs. " << v2 << ")";
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std::string* msg = new std::string(ss.str());
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return msg;
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}
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// MSVC doesn't like complex extern templates and DLLs.
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#if !defined(COMPILER_MSVC)
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// Commonly used instantiations of MakeCheckOpString<>. Explicitly instantiated
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// in logging.cc.
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extern template std::string* MakeCheckOpString<int, int>(
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const int&, const int&, const char* names);
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extern template
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std::string* MakeCheckOpString<unsigned long, unsigned long>(
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const unsigned long&, const unsigned long&, const char* names);
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extern template
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std::string* MakeCheckOpString<unsigned long, unsigned int>(
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const unsigned long&, const unsigned int&, const char* names);
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extern template
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std::string* MakeCheckOpString<unsigned int, unsigned long>(
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const unsigned int&, const unsigned long&, const char* names);
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extern template
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std::string* MakeCheckOpString<std::string, std::string>(
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const std::string&, const std::string&, const char* name);
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#endif
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// Helper functions for RTC_CHECK_OP macro.
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// The (int, int) specialization works around the issue that the compiler
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// will not instantiate the template version of the function on values of
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// unnamed enum type - see comment below.
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#define DEFINE_RTC_CHECK_OP_IMPL(name, op) \
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template <class t1, class t2> \
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inline std::string* Check##name##Impl(const t1& v1, const t2& v2, \
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const char* names) { \
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if (v1 op v2) \
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return NULL; \
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else \
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return rtc::MakeCheckOpString(v1, v2, names); \
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} \
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inline std::string* Check##name##Impl(int v1, int v2, const char* names) { \
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if (v1 op v2) \
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return NULL; \
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else \
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return rtc::MakeCheckOpString(v1, v2, names); \
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}
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DEFINE_RTC_CHECK_OP_IMPL(EQ, ==)
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DEFINE_RTC_CHECK_OP_IMPL(NE, !=)
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DEFINE_RTC_CHECK_OP_IMPL(LE, <=)
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DEFINE_RTC_CHECK_OP_IMPL(LT, < )
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DEFINE_RTC_CHECK_OP_IMPL(GE, >=)
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DEFINE_RTC_CHECK_OP_IMPL(GT, > )
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#undef DEFINE_RTC_CHECK_OP_IMPL
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#define RTC_CHECK_EQ(val1, val2) RTC_CHECK_OP(EQ, ==, val1, val2)
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#define RTC_CHECK_NE(val1, val2) RTC_CHECK_OP(NE, !=, val1, val2)
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#define RTC_CHECK_LE(val1, val2) RTC_CHECK_OP(LE, <=, val1, val2)
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#define RTC_CHECK_LT(val1, val2) RTC_CHECK_OP(LT, < , val1, val2)
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#define RTC_CHECK_GE(val1, val2) RTC_CHECK_OP(GE, >=, val1, val2)
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#define RTC_CHECK_GT(val1, val2) RTC_CHECK_OP(GT, > , val1, val2)
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// The RTC_DCHECK macro is equivalent to RTC_CHECK except that it only generates
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// code in debug builds. It does reference the condition parameter in all cases,
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// though, so callers won't risk getting warnings about unused variables.
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#if (!defined(NDEBUG) || defined(DCHECK_ALWAYS_ON))
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#define RTC_DCHECK(condition) RTC_CHECK(condition)
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#define RTC_DCHECK_EQ(v1, v2) RTC_CHECK_EQ(v1, v2)
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#define RTC_DCHECK_NE(v1, v2) RTC_CHECK_NE(v1, v2)
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#define RTC_DCHECK_LE(v1, v2) RTC_CHECK_LE(v1, v2)
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#define RTC_DCHECK_LT(v1, v2) RTC_CHECK_LT(v1, v2)
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#define RTC_DCHECK_GE(v1, v2) RTC_CHECK_GE(v1, v2)
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#define RTC_DCHECK_GT(v1, v2) RTC_CHECK_GT(v1, v2)
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#else
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#define RTC_DCHECK(condition) RTC_EAT_STREAM_PARAMETERS(condition)
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#define RTC_DCHECK_EQ(v1, v2) RTC_EAT_STREAM_PARAMETERS((v1) == (v2))
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#define RTC_DCHECK_NE(v1, v2) RTC_EAT_STREAM_PARAMETERS((v1) != (v2))
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#define RTC_DCHECK_LE(v1, v2) RTC_EAT_STREAM_PARAMETERS((v1) <= (v2))
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#define RTC_DCHECK_LT(v1, v2) RTC_EAT_STREAM_PARAMETERS((v1) < (v2))
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#define RTC_DCHECK_GE(v1, v2) RTC_EAT_STREAM_PARAMETERS((v1) >= (v2))
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#define RTC_DCHECK_GT(v1, v2) RTC_EAT_STREAM_PARAMETERS((v1) > (v2))
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#endif
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// This is identical to LogMessageVoidify but in name.
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class FatalMessageVoidify {
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public:
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FatalMessageVoidify() { }
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// This has to be an operator with a precedence lower than << but
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// higher than ?:
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void operator&(std::ostream&) { }
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};
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#define RTC_UNREACHABLE_CODE_HIT false
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#define RTC_NOTREACHED() RTC_DCHECK(RTC_UNREACHABLE_CODE_HIT)
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#define FATAL() rtc::FatalMessage(__FILE__, __LINE__).stream()
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// TODO(ajm): Consider adding RTC_NOTIMPLEMENTED macro when
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// base/logging.h and system_wrappers/logging.h are consolidated such that we
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// can match the Chromium behavior.
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// Like a stripped-down LogMessage from logging.h, except that it aborts.
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class FatalMessage {
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public:
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FatalMessage(const char* file, int line);
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// Used for RTC_CHECK_EQ(), etc. Takes ownership of the given string.
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FatalMessage(const char* file, int line, std::string* result);
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NO_RETURN ~FatalMessage();
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std::ostream& stream() { return stream_; }
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private:
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void Init(const char* file, int line);
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std::ostringstream stream_;
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};
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// Performs the integer division a/b and returns the result. CHECKs that the
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// remainder is zero.
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template <typename T>
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inline T CheckedDivExact(T a, T b) {
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RTC_CHECK_EQ(a % b, static_cast<T>(0));
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return a / b;
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}
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} // namespace rtc
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#endif // WEBRTC_BASE_CHECKS_H_
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34
webrtc/base/constructormagic.h
Normal file
34
webrtc/base/constructormagic.h
Normal file
@ -0,0 +1,34 @@
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/*
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* Copyright 2004 The WebRTC Project Authors. All rights reserved.
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*
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* Use of this source code is governed by a BSD-style license
|
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* that can be found in the LICENSE file in the root of the source
|
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* tree. An additional intellectual property rights grant can be found
|
||||
* in the file PATENTS. All contributing project authors may
|
||||
* be found in the AUTHORS file in the root of the source tree.
|
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*/
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#ifndef WEBRTC_BASE_CONSTRUCTORMAGIC_H_
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#define WEBRTC_BASE_CONSTRUCTORMAGIC_H_
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// Put this in the declarations for a class to be unassignable.
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#define RTC_DISALLOW_ASSIGN(TypeName) \
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void operator=(const TypeName&) = delete
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// A macro to disallow the copy constructor and operator= functions. This should
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// be used in the declarations for a class.
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#define RTC_DISALLOW_COPY_AND_ASSIGN(TypeName) \
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TypeName(const TypeName&) = delete; \
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RTC_DISALLOW_ASSIGN(TypeName)
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// A macro to disallow all the implicit constructors, namely the default
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// constructor, copy constructor and operator= functions.
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//
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// This should be used in the declarations for a class that wants to prevent
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// anyone from instantiating it. This is especially useful for classes
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// containing only static methods.
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#define RTC_DISALLOW_IMPLICIT_CONSTRUCTORS(TypeName) \
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TypeName() = delete; \
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RTC_DISALLOW_COPY_AND_ASSIGN(TypeName)
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#endif // WEBRTC_BASE_CONSTRUCTORMAGIC_H_
|
636
webrtc/base/scoped_ptr.h
Normal file
636
webrtc/base/scoped_ptr.h
Normal file
@ -0,0 +1,636 @@
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/*
|
||||
* Copyright 2012 The WebRTC Project Authors. All rights reserved.
|
||||
*
|
||||
* Use of this source code is governed by a BSD-style license
|
||||
* that can be found in the LICENSE file in the root of the source
|
||||
* tree. An additional intellectual property rights grant can be found
|
||||
* in the file PATENTS. All contributing project authors may
|
||||
* be found in the AUTHORS file in the root of the source tree.
|
||||
*/
|
||||
|
||||
// Borrowed from Chromium's src/base/memory/scoped_ptr.h.
|
||||
|
||||
// Scopers help you manage ownership of a pointer, helping you easily manage a
|
||||
// pointer within a scope, and automatically destroying the pointer at the end
|
||||
// of a scope. There are two main classes you will use, which correspond to the
|
||||
// operators new/delete and new[]/delete[].
|
||||
//
|
||||
// Example usage (scoped_ptr<T>):
|
||||
// {
|
||||
// scoped_ptr<Foo> foo(new Foo("wee"));
|
||||
// } // foo goes out of scope, releasing the pointer with it.
|
||||
//
|
||||
// {
|
||||
// scoped_ptr<Foo> foo; // No pointer managed.
|
||||
// foo.reset(new Foo("wee")); // Now a pointer is managed.
|
||||
// foo.reset(new Foo("wee2")); // Foo("wee") was destroyed.
|
||||
// foo.reset(new Foo("wee3")); // Foo("wee2") was destroyed.
|
||||
// foo->Method(); // Foo::Method() called.
|
||||
// foo.get()->Method(); // Foo::Method() called.
|
||||
// SomeFunc(foo.release()); // SomeFunc takes ownership, foo no longer
|
||||
// // manages a pointer.
|
||||
// foo.reset(new Foo("wee4")); // foo manages a pointer again.
|
||||
// foo.reset(); // Foo("wee4") destroyed, foo no longer
|
||||
// // manages a pointer.
|
||||
// } // foo wasn't managing a pointer, so nothing was destroyed.
|
||||
//
|
||||
// Example usage (scoped_ptr<T[]>):
|
||||
// {
|
||||
// scoped_ptr<Foo[]> foo(new Foo[100]);
|
||||
// foo.get()->Method(); // Foo::Method on the 0th element.
|
||||
// foo[10].Method(); // Foo::Method on the 10th element.
|
||||
// }
|
||||
//
|
||||
// These scopers also implement part of the functionality of C++11 unique_ptr
|
||||
// in that they are "movable but not copyable." You can use the scopers in
|
||||
// the parameter and return types of functions to signify ownership transfer
|
||||
// in to and out of a function. When calling a function that has a scoper
|
||||
// as the argument type, it must be called with the result of an analogous
|
||||
// scoper's Pass() function or another function that generates a temporary;
|
||||
// passing by copy will NOT work. Here is an example using scoped_ptr:
|
||||
//
|
||||
// void TakesOwnership(scoped_ptr<Foo> arg) {
|
||||
// // Do something with arg
|
||||
// }
|
||||
// scoped_ptr<Foo> CreateFoo() {
|
||||
// // No need for calling Pass() because we are constructing a temporary
|
||||
// // for the return value.
|
||||
// return scoped_ptr<Foo>(new Foo("new"));
|
||||
// }
|
||||
// scoped_ptr<Foo> PassThru(scoped_ptr<Foo> arg) {
|
||||
// return arg.Pass();
|
||||
// }
|
||||
//
|
||||
// {
|
||||
// scoped_ptr<Foo> ptr(new Foo("yay")); // ptr manages Foo("yay").
|
||||
// TakesOwnership(ptr.Pass()); // ptr no longer owns Foo("yay").
|
||||
// scoped_ptr<Foo> ptr2 = CreateFoo(); // ptr2 owns the return Foo.
|
||||
// scoped_ptr<Foo> ptr3 = // ptr3 now owns what was in ptr2.
|
||||
// PassThru(ptr2.Pass()); // ptr2 is correspondingly nullptr.
|
||||
// }
|
||||
//
|
||||
// Notice that if you do not call Pass() when returning from PassThru(), or
|
||||
// when invoking TakesOwnership(), the code will not compile because scopers
|
||||
// are not copyable; they only implement move semantics which require calling
|
||||
// the Pass() function to signify a destructive transfer of state. CreateFoo()
|
||||
// is different though because we are constructing a temporary on the return
|
||||
// line and thus can avoid needing to call Pass().
|
||||
//
|
||||
// Pass() properly handles upcast in initialization, i.e. you can use a
|
||||
// scoped_ptr<Child> to initialize a scoped_ptr<Parent>:
|
||||
//
|
||||
// scoped_ptr<Foo> foo(new Foo());
|
||||
// scoped_ptr<FooParent> parent(foo.Pass());
|
||||
//
|
||||
// PassAs<>() should be used to upcast return value in return statement:
|
||||
//
|
||||
// scoped_ptr<Foo> CreateFoo() {
|
||||
// scoped_ptr<FooChild> result(new FooChild());
|
||||
// return result.PassAs<Foo>();
|
||||
// }
|
||||
//
|
||||
// Note that PassAs<>() is implemented only for scoped_ptr<T>, but not for
|
||||
// scoped_ptr<T[]>. This is because casting array pointers may not be safe.
|
||||
|
||||
#ifndef WEBRTC_BASE_SCOPED_PTR_H__
|
||||
#define WEBRTC_BASE_SCOPED_PTR_H__
|
||||
|
||||
// This is an implementation designed to match the anticipated future TR2
|
||||
// implementation of the scoped_ptr class.
|
||||
|
||||
#include <assert.h>
|
||||
#include <stddef.h>
|
||||
#include <stdlib.h>
|
||||
|
||||
#include <algorithm> // For std::swap().
|
||||
|
||||
#include "webrtc/base/constructormagic.h"
|
||||
#include "webrtc/base/template_util.h"
|
||||
#include "webrtc/typedefs.h"
|
||||
|
||||
namespace rtc {
|
||||
|
||||
// Function object which deletes its parameter, which must be a pointer.
|
||||
// If C is an array type, invokes 'delete[]' on the parameter; otherwise,
|
||||
// invokes 'delete'. The default deleter for scoped_ptr<T>.
|
||||
template <class T>
|
||||
struct DefaultDeleter {
|
||||
DefaultDeleter() {}
|
||||
template <typename U> DefaultDeleter(const DefaultDeleter<U>& other) {
|
||||
// IMPLEMENTATION NOTE: C++11 20.7.1.1.2p2 only provides this constructor
|
||||
// if U* is implicitly convertible to T* and U is not an array type.
|
||||
//
|
||||
// Correct implementation should use SFINAE to disable this
|
||||
// constructor. However, since there are no other 1-argument constructors,
|
||||
// using a static_assert based on is_convertible<> and requiring
|
||||
// complete types is simpler and will cause compile failures for equivalent
|
||||
// misuses.
|
||||
//
|
||||
// Note, the is_convertible<U*, T*> check also ensures that U is not an
|
||||
// array. T is guaranteed to be a non-array, so any U* where U is an array
|
||||
// cannot convert to T*.
|
||||
enum { T_must_be_complete = sizeof(T) };
|
||||
enum { U_must_be_complete = sizeof(U) };
|
||||
static_assert(rtc::is_convertible<U*, T*>::value,
|
||||
"U* must implicitly convert to T*");
|
||||
}
|
||||
inline void operator()(T* ptr) const {
|
||||
enum { type_must_be_complete = sizeof(T) };
|
||||
delete ptr;
|
||||
}
|
||||
};
|
||||
|
||||
// Specialization of DefaultDeleter for array types.
|
||||
template <class T>
|
||||
struct DefaultDeleter<T[]> {
|
||||
inline void operator()(T* ptr) const {
|
||||
enum { type_must_be_complete = sizeof(T) };
|
||||
delete[] ptr;
|
||||
}
|
||||
|
||||
private:
|
||||
// Disable this operator for any U != T because it is undefined to execute
|
||||
// an array delete when the static type of the array mismatches the dynamic
|
||||
// type.
|
||||
//
|
||||
// References:
|
||||
// C++98 [expr.delete]p3
|
||||
// http://cplusplus.github.com/LWG/lwg-defects.html#938
|
||||
template <typename U> void operator()(U* array) const;
|
||||
};
|
||||
|
||||
template <class T, int n>
|
||||
struct DefaultDeleter<T[n]> {
|
||||
// Never allow someone to declare something like scoped_ptr<int[10]>.
|
||||
static_assert(sizeof(T) == -1, "do not use array with size as type");
|
||||
};
|
||||
|
||||
// Function object which invokes 'free' on its parameter, which must be
|
||||
// a pointer. Can be used to store malloc-allocated pointers in scoped_ptr:
|
||||
//
|
||||
// scoped_ptr<int, rtc::FreeDeleter> foo_ptr(
|
||||
// static_cast<int*>(malloc(sizeof(int))));
|
||||
struct FreeDeleter {
|
||||
inline void operator()(void* ptr) const {
|
||||
free(ptr);
|
||||
}
|
||||
};
|
||||
|
||||
namespace internal {
|
||||
|
||||
template <typename T>
|
||||
struct ShouldAbortOnSelfReset {
|
||||
template <typename U>
|
||||
static rtc::internal::NoType Test(const typename U::AllowSelfReset*);
|
||||
|
||||
template <typename U>
|
||||
static rtc::internal::YesType Test(...);
|
||||
|
||||
static const bool value =
|
||||
sizeof(Test<T>(0)) == sizeof(rtc::internal::YesType);
|
||||
};
|
||||
|
||||
// Minimal implementation of the core logic of scoped_ptr, suitable for
|
||||
// reuse in both scoped_ptr and its specializations.
|
||||
template <class T, class D>
|
||||
class scoped_ptr_impl {
|
||||
public:
|
||||
explicit scoped_ptr_impl(T* p) : data_(p) {}
|
||||
|
||||
// Initializer for deleters that have data parameters.
|
||||
scoped_ptr_impl(T* p, const D& d) : data_(p, d) {}
|
||||
|
||||
// Templated constructor that destructively takes the value from another
|
||||
// scoped_ptr_impl.
|
||||
template <typename U, typename V>
|
||||
scoped_ptr_impl(scoped_ptr_impl<U, V>* other)
|
||||
: data_(other->release(), other->get_deleter()) {
|
||||
// We do not support move-only deleters. We could modify our move
|
||||
// emulation to have rtc::subtle::move() and rtc::subtle::forward()
|
||||
// functions that are imperfect emulations of their C++11 equivalents,
|
||||
// but until there's a requirement, just assume deleters are copyable.
|
||||
}
|
||||
|
||||
template <typename U, typename V>
|
||||
void TakeState(scoped_ptr_impl<U, V>* other) {
|
||||
// See comment in templated constructor above regarding lack of support
|
||||
// for move-only deleters.
|
||||
reset(other->release());
|
||||
get_deleter() = other->get_deleter();
|
||||
}
|
||||
|
||||
~scoped_ptr_impl() {
|
||||
if (data_.ptr != nullptr) {
|
||||
// Not using get_deleter() saves one function call in non-optimized
|
||||
// builds.
|
||||
static_cast<D&>(data_)(data_.ptr);
|
||||
}
|
||||
}
|
||||
|
||||
void reset(T* p) {
|
||||
// This is a self-reset, which is no longer allowed for default deleters:
|
||||
// https://crbug.com/162971
|
||||
assert(!ShouldAbortOnSelfReset<D>::value || p == nullptr || p != data_.ptr);
|
||||
|
||||
// Note that running data_.ptr = p can lead to undefined behavior if
|
||||
// get_deleter()(get()) deletes this. In order to prevent this, reset()
|
||||
// should update the stored pointer before deleting its old value.
|
||||
//
|
||||
// However, changing reset() to use that behavior may cause current code to
|
||||
// break in unexpected ways. If the destruction of the owned object
|
||||
// dereferences the scoped_ptr when it is destroyed by a call to reset(),
|
||||
// then it will incorrectly dispatch calls to |p| rather than the original
|
||||
// value of |data_.ptr|.
|
||||
//
|
||||
// During the transition period, set the stored pointer to nullptr while
|
||||
// deleting the object. Eventually, this safety check will be removed to
|
||||
// prevent the scenario initially described from occurring and
|
||||
// http://crbug.com/176091 can be closed.
|
||||
T* old = data_.ptr;
|
||||
data_.ptr = nullptr;
|
||||
if (old != nullptr)
|
||||
static_cast<D&>(data_)(old);
|
||||
data_.ptr = p;
|
||||
}
|
||||
|
||||
T* get() const { return data_.ptr; }
|
||||
|
||||
D& get_deleter() { return data_; }
|
||||
const D& get_deleter() const { return data_; }
|
||||
|
||||
void swap(scoped_ptr_impl& p2) {
|
||||
// Standard swap idiom: 'using std::swap' ensures that std::swap is
|
||||
// present in the overload set, but we call swap unqualified so that
|
||||
// any more-specific overloads can be used, if available.
|
||||
using std::swap;
|
||||
swap(static_cast<D&>(data_), static_cast<D&>(p2.data_));
|
||||
swap(data_.ptr, p2.data_.ptr);
|
||||
}
|
||||
|
||||
T* release() {
|
||||
T* old_ptr = data_.ptr;
|
||||
data_.ptr = nullptr;
|
||||
return old_ptr;
|
||||
}
|
||||
|
||||
T** accept() {
|
||||
reset(nullptr);
|
||||
return &(data_.ptr);
|
||||
}
|
||||
|
||||
T** use() {
|
||||
return &(data_.ptr);
|
||||
}
|
||||
|
||||
private:
|
||||
// Needed to allow type-converting constructor.
|
||||
template <typename U, typename V> friend class scoped_ptr_impl;
|
||||
|
||||
// Use the empty base class optimization to allow us to have a D
|
||||
// member, while avoiding any space overhead for it when D is an
|
||||
// empty class. See e.g. http://www.cantrip.org/emptyopt.html for a good
|
||||
// discussion of this technique.
|
||||
struct Data : public D {
|
||||
explicit Data(T* ptr_in) : ptr(ptr_in) {}
|
||||
Data(T* ptr_in, const D& other) : D(other), ptr(ptr_in) {}
|
||||
T* ptr;
|
||||
};
|
||||
|
||||
Data data_;
|
||||
|
||||
RTC_DISALLOW_COPY_AND_ASSIGN(scoped_ptr_impl);
|
||||
};
|
||||
|
||||
} // namespace internal
|
||||
|
||||
// A scoped_ptr<T> is like a T*, except that the destructor of scoped_ptr<T>
|
||||
// automatically deletes the pointer it holds (if any).
|
||||
// That is, scoped_ptr<T> owns the T object that it points to.
|
||||
// Like a T*, a scoped_ptr<T> may hold either nullptr or a pointer to a T
|
||||
// object. Also like T*, scoped_ptr<T> is thread-compatible, and once you
|
||||
// dereference it, you get the thread safety guarantees of T.
|
||||
//
|
||||
// The size of scoped_ptr is small. On most compilers, when using the
|
||||
// DefaultDeleter, sizeof(scoped_ptr<T>) == sizeof(T*). Custom deleters will
|
||||
// increase the size proportional to whatever state they need to have. See
|
||||
// comments inside scoped_ptr_impl<> for details.
|
||||
//
|
||||
// Current implementation targets having a strict subset of C++11's
|
||||
// unique_ptr<> features. Known deficiencies include not supporting move-only
|
||||
// deleters, function pointers as deleters, and deleters with reference
|
||||
// types.
|
||||
template <class T, class D = rtc::DefaultDeleter<T> >
|
||||
class scoped_ptr {
|
||||
|
||||
// TODO(ajm): If we ever import RefCountedBase, this check needs to be
|
||||
// enabled.
|
||||
//static_assert(rtc::internal::IsNotRefCounted<T>::value,
|
||||
// "T is refcounted type and needs scoped refptr");
|
||||
|
||||
public:
|
||||
// The element and deleter types.
|
||||
typedef T element_type;
|
||||
typedef D deleter_type;
|
||||
|
||||
// Constructor. Defaults to initializing with nullptr.
|
||||
scoped_ptr() : impl_(nullptr) {}
|
||||
|
||||
// Constructor. Takes ownership of p.
|
||||
explicit scoped_ptr(element_type* p) : impl_(p) {}
|
||||
|
||||
// Constructor. Allows initialization of a stateful deleter.
|
||||
scoped_ptr(element_type* p, const D& d) : impl_(p, d) {}
|
||||
|
||||
// Constructor. Allows construction from a nullptr.
|
||||
scoped_ptr(decltype(nullptr)) : impl_(nullptr) {}
|
||||
|
||||
// Constructor. Allows construction from a scoped_ptr rvalue for a
|
||||
// convertible type and deleter.
|
||||
//
|
||||
// IMPLEMENTATION NOTE: C++11 unique_ptr<> keeps this constructor distinct
|
||||
// from the normal move constructor. By C++11 20.7.1.2.1.21, this constructor
|
||||
// has different post-conditions if D is a reference type. Since this
|
||||
// implementation does not support deleters with reference type,
|
||||
// we do not need a separate move constructor allowing us to avoid one
|
||||
// use of SFINAE. You only need to care about this if you modify the
|
||||
// implementation of scoped_ptr.
|
||||
template <typename U, typename V>
|
||||
scoped_ptr(scoped_ptr<U, V>&& other)
|
||||
: impl_(&other.impl_) {
|
||||
static_assert(!rtc::is_array<U>::value, "U cannot be an array");
|
||||
}
|
||||
|
||||
// operator=. Allows assignment from a scoped_ptr rvalue for a convertible
|
||||
// type and deleter.
|
||||
//
|
||||
// IMPLEMENTATION NOTE: C++11 unique_ptr<> keeps this operator= distinct from
|
||||
// the normal move assignment operator. By C++11 20.7.1.2.3.4, this templated
|
||||
// form has different requirements on for move-only Deleters. Since this
|
||||
// implementation does not support move-only Deleters, we do not need a
|
||||
// separate move assignment operator allowing us to avoid one use of SFINAE.
|
||||
// You only need to care about this if you modify the implementation of
|
||||
// scoped_ptr.
|
||||
template <typename U, typename V>
|
||||
scoped_ptr& operator=(scoped_ptr<U, V>&& rhs) {
|
||||
static_assert(!rtc::is_array<U>::value, "U cannot be an array");
|
||||
impl_.TakeState(&rhs.impl_);
|
||||
return *this;
|
||||
}
|
||||
|
||||
// operator=. Allows assignment from a nullptr. Deletes the currently owned
|
||||
// object, if any.
|
||||
scoped_ptr& operator=(decltype(nullptr)) {
|
||||
reset();
|
||||
return *this;
|
||||
}
|
||||
|
||||
// Deleted copy constructor and copy assignment, to make the type move-only.
|
||||
scoped_ptr(const scoped_ptr& other) = delete;
|
||||
scoped_ptr& operator=(const scoped_ptr& other) = delete;
|
||||
|
||||
// Get an rvalue reference. (sp.Pass() does the same thing as std::move(sp).)
|
||||
scoped_ptr&& Pass() { return static_cast<scoped_ptr&&>(*this); }
|
||||
|
||||
// Reset. Deletes the currently owned object, if any.
|
||||
// Then takes ownership of a new object, if given.
|
||||
void reset(element_type* p = nullptr) { impl_.reset(p); }
|
||||
|
||||
// Accessors to get the owned object.
|
||||
// operator* and operator-> will assert() if there is no current object.
|
||||
element_type& operator*() const {
|
||||
assert(impl_.get() != nullptr);
|
||||
return *impl_.get();
|
||||
}
|
||||
element_type* operator->() const {
|
||||
assert(impl_.get() != nullptr);
|
||||
return impl_.get();
|
||||
}
|
||||
element_type* get() const { return impl_.get(); }
|
||||
|
||||
// Access to the deleter.
|
||||
deleter_type& get_deleter() { return impl_.get_deleter(); }
|
||||
const deleter_type& get_deleter() const { return impl_.get_deleter(); }
|
||||
|
||||
// Allow scoped_ptr<element_type> to be used in boolean expressions, but not
|
||||
// implicitly convertible to a real bool (which is dangerous).
|
||||
//
|
||||
// Note that this trick is only safe when the == and != operators
|
||||
// are declared explicitly, as otherwise "scoped_ptr1 ==
|
||||
// scoped_ptr2" will compile but do the wrong thing (i.e., convert
|
||||
// to Testable and then do the comparison).
|
||||
private:
|
||||
typedef rtc::internal::scoped_ptr_impl<element_type, deleter_type>
|
||||
scoped_ptr::*Testable;
|
||||
|
||||
public:
|
||||
operator Testable() const {
|
||||
return impl_.get() ? &scoped_ptr::impl_ : nullptr;
|
||||
}
|
||||
|
||||
// Comparison operators.
|
||||
// These return whether two scoped_ptr refer to the same object, not just to
|
||||
// two different but equal objects.
|
||||
bool operator==(const element_type* p) const { return impl_.get() == p; }
|
||||
bool operator!=(const element_type* p) const { return impl_.get() != p; }
|
||||
|
||||
// Swap two scoped pointers.
|
||||
void swap(scoped_ptr& p2) {
|
||||
impl_.swap(p2.impl_);
|
||||
}
|
||||
|
||||
// Release a pointer.
|
||||
// The return value is the current pointer held by this object. If this object
|
||||
// holds a nullptr, the return value is nullptr. After this operation, this
|
||||
// object will hold a nullptr, and will not own the object any more.
|
||||
element_type* release() WARN_UNUSED_RESULT {
|
||||
return impl_.release();
|
||||
}
|
||||
|
||||
// Delete the currently held pointer and return a pointer
|
||||
// to allow overwriting of the current pointer address.
|
||||
element_type** accept() WARN_UNUSED_RESULT {
|
||||
return impl_.accept();
|
||||
}
|
||||
|
||||
// Return a pointer to the current pointer address.
|
||||
element_type** use() WARN_UNUSED_RESULT {
|
||||
return impl_.use();
|
||||
}
|
||||
|
||||
private:
|
||||
// Needed to reach into |impl_| in the constructor.
|
||||
template <typename U, typename V> friend class scoped_ptr;
|
||||
rtc::internal::scoped_ptr_impl<element_type, deleter_type> impl_;
|
||||
|
||||
// Forbidden for API compatibility with std::unique_ptr.
|
||||
explicit scoped_ptr(int disallow_construction_from_null);
|
||||
|
||||
// Forbid comparison of scoped_ptr types. If U != T, it totally
|
||||
// doesn't make sense, and if U == T, it still doesn't make sense
|
||||
// because you should never have the same object owned by two different
|
||||
// scoped_ptrs.
|
||||
template <class U> bool operator==(scoped_ptr<U> const& p2) const;
|
||||
template <class U> bool operator!=(scoped_ptr<U> const& p2) const;
|
||||
};
|
||||
|
||||
template <class T, class D>
|
||||
class scoped_ptr<T[], D> {
|
||||
public:
|
||||
// The element and deleter types.
|
||||
typedef T element_type;
|
||||
typedef D deleter_type;
|
||||
|
||||
// Constructor. Defaults to initializing with nullptr.
|
||||
scoped_ptr() : impl_(nullptr) {}
|
||||
|
||||
// Constructor. Stores the given array. Note that the argument's type
|
||||
// must exactly match T*. In particular:
|
||||
// - it cannot be a pointer to a type derived from T, because it is
|
||||
// inherently unsafe in the general case to access an array through a
|
||||
// pointer whose dynamic type does not match its static type (eg., if
|
||||
// T and the derived types had different sizes access would be
|
||||
// incorrectly calculated). Deletion is also always undefined
|
||||
// (C++98 [expr.delete]p3). If you're doing this, fix your code.
|
||||
// - it cannot be const-qualified differently from T per unique_ptr spec
|
||||
// (http://cplusplus.github.com/LWG/lwg-active.html#2118). Users wanting
|
||||
// to work around this may use implicit_cast<const T*>().
|
||||
// However, because of the first bullet in this comment, users MUST
|
||||
// NOT use implicit_cast<Base*>() to upcast the static type of the array.
|
||||
explicit scoped_ptr(element_type* array) : impl_(array) {}
|
||||
|
||||
// Constructor. Allows construction from a nullptr.
|
||||
scoped_ptr(decltype(nullptr)) : impl_(nullptr) {}
|
||||
|
||||
// Constructor. Allows construction from a scoped_ptr rvalue.
|
||||
scoped_ptr(scoped_ptr&& other) : impl_(&other.impl_) {}
|
||||
|
||||
// operator=. Allows assignment from a scoped_ptr rvalue.
|
||||
scoped_ptr& operator=(scoped_ptr&& rhs) {
|
||||
impl_.TakeState(&rhs.impl_);
|
||||
return *this;
|
||||
}
|
||||
|
||||
// operator=. Allows assignment from a nullptr. Deletes the currently owned
|
||||
// array, if any.
|
||||
scoped_ptr& operator=(decltype(nullptr)) {
|
||||
reset();
|
||||
return *this;
|
||||
}
|
||||
|
||||
// Deleted copy constructor and copy assignment, to make the type move-only.
|
||||
scoped_ptr(const scoped_ptr& other) = delete;
|
||||
scoped_ptr& operator=(const scoped_ptr& other) = delete;
|
||||
|
||||
// Get an rvalue reference. (sp.Pass() does the same thing as std::move(sp).)
|
||||
scoped_ptr&& Pass() { return static_cast<scoped_ptr&&>(*this); }
|
||||
|
||||
// Reset. Deletes the currently owned array, if any.
|
||||
// Then takes ownership of a new object, if given.
|
||||
void reset(element_type* array = nullptr) { impl_.reset(array); }
|
||||
|
||||
// Accessors to get the owned array.
|
||||
element_type& operator[](size_t i) const {
|
||||
assert(impl_.get() != nullptr);
|
||||
return impl_.get()[i];
|
||||
}
|
||||
element_type* get() const { return impl_.get(); }
|
||||
|
||||
// Access to the deleter.
|
||||
deleter_type& get_deleter() { return impl_.get_deleter(); }
|
||||
const deleter_type& get_deleter() const { return impl_.get_deleter(); }
|
||||
|
||||
// Allow scoped_ptr<element_type> to be used in boolean expressions, but not
|
||||
// implicitly convertible to a real bool (which is dangerous).
|
||||
private:
|
||||
typedef rtc::internal::scoped_ptr_impl<element_type, deleter_type>
|
||||
scoped_ptr::*Testable;
|
||||
|
||||
public:
|
||||
operator Testable() const {
|
||||
return impl_.get() ? &scoped_ptr::impl_ : nullptr;
|
||||
}
|
||||
|
||||
// Comparison operators.
|
||||
// These return whether two scoped_ptr refer to the same object, not just to
|
||||
// two different but equal objects.
|
||||
bool operator==(element_type* array) const { return impl_.get() == array; }
|
||||
bool operator!=(element_type* array) const { return impl_.get() != array; }
|
||||
|
||||
// Swap two scoped pointers.
|
||||
void swap(scoped_ptr& p2) {
|
||||
impl_.swap(p2.impl_);
|
||||
}
|
||||
|
||||
// Release a pointer.
|
||||
// The return value is the current pointer held by this object. If this object
|
||||
// holds a nullptr, the return value is nullptr. After this operation, this
|
||||
// object will hold a nullptr, and will not own the object any more.
|
||||
element_type* release() WARN_UNUSED_RESULT {
|
||||
return impl_.release();
|
||||
}
|
||||
|
||||
// Delete the currently held pointer and return a pointer
|
||||
// to allow overwriting of the current pointer address.
|
||||
element_type** accept() WARN_UNUSED_RESULT {
|
||||
return impl_.accept();
|
||||
}
|
||||
|
||||
// Return a pointer to the current pointer address.
|
||||
element_type** use() WARN_UNUSED_RESULT {
|
||||
return impl_.use();
|
||||
}
|
||||
|
||||
private:
|
||||
// Force element_type to be a complete type.
|
||||
enum { type_must_be_complete = sizeof(element_type) };
|
||||
|
||||
// Actually hold the data.
|
||||
rtc::internal::scoped_ptr_impl<element_type, deleter_type> impl_;
|
||||
|
||||
// Disable initialization from any type other than element_type*, by
|
||||
// providing a constructor that matches such an initialization, but is
|
||||
// private and has no definition. This is disabled because it is not safe to
|
||||
// call delete[] on an array whose static type does not match its dynamic
|
||||
// type.
|
||||
template <typename U> explicit scoped_ptr(U* array);
|
||||
explicit scoped_ptr(int disallow_construction_from_null);
|
||||
|
||||
// Disable reset() from any type other than element_type*, for the same
|
||||
// reasons as the constructor above.
|
||||
template <typename U> void reset(U* array);
|
||||
void reset(int disallow_reset_from_null);
|
||||
|
||||
// Forbid comparison of scoped_ptr types. If U != T, it totally
|
||||
// doesn't make sense, and if U == T, it still doesn't make sense
|
||||
// because you should never have the same object owned by two different
|
||||
// scoped_ptrs.
|
||||
template <class U> bool operator==(scoped_ptr<U> const& p2) const;
|
||||
template <class U> bool operator!=(scoped_ptr<U> const& p2) const;
|
||||
};
|
||||
|
||||
template <class T, class D>
|
||||
void swap(rtc::scoped_ptr<T, D>& p1, rtc::scoped_ptr<T, D>& p2) {
|
||||
p1.swap(p2);
|
||||
}
|
||||
|
||||
} // namespace rtc
|
||||
|
||||
template <class T, class D>
|
||||
bool operator==(T* p1, const rtc::scoped_ptr<T, D>& p2) {
|
||||
return p1 == p2.get();
|
||||
}
|
||||
|
||||
template <class T, class D>
|
||||
bool operator!=(T* p1, const rtc::scoped_ptr<T, D>& p2) {
|
||||
return p1 != p2.get();
|
||||
}
|
||||
|
||||
// A function to convert T* into scoped_ptr<T>
|
||||
// Doing e.g. make_scoped_ptr(new FooBarBaz<type>(arg)) is a shorter notation
|
||||
// for scoped_ptr<FooBarBaz<type> >(new FooBarBaz<type>(arg))
|
||||
template <typename T>
|
||||
rtc::scoped_ptr<T> rtc_make_scoped_ptr(T* ptr) {
|
||||
return rtc::scoped_ptr<T>(ptr);
|
||||
}
|
||||
|
||||
#endif // #ifndef WEBRTC_BASE_SCOPED_PTR_H__
|
114
webrtc/base/template_util.h
Normal file
114
webrtc/base/template_util.h
Normal file
@ -0,0 +1,114 @@
|
||||
/*
|
||||
* Copyright (c) 2013 The WebRTC project authors. All Rights Reserved.
|
||||
*
|
||||
* Use of this source code is governed by a BSD-style license
|
||||
* that can be found in the LICENSE file in the root of the source
|
||||
* tree. An additional intellectual property rights grant can be found
|
||||
* in the file PATENTS. All contributing project authors may
|
||||
* be found in the AUTHORS file in the root of the source tree.
|
||||
*/
|
||||
|
||||
// Borrowed from Chromium's src/base/template_util.h.
|
||||
|
||||
#ifndef WEBRTC_BASE_TEMPLATE_UTIL_H_
|
||||
#define WEBRTC_BASE_TEMPLATE_UTIL_H_
|
||||
|
||||
#include <stddef.h> // For size_t.
|
||||
|
||||
namespace rtc {
|
||||
|
||||
// Template definitions from tr1.
|
||||
|
||||
template<class T, T v>
|
||||
struct integral_constant {
|
||||
static const T value = v;
|
||||
typedef T value_type;
|
||||
typedef integral_constant<T, v> type;
|
||||
};
|
||||
|
||||
template <class T, T v> const T integral_constant<T, v>::value;
|
||||
|
||||
typedef integral_constant<bool, true> true_type;
|
||||
typedef integral_constant<bool, false> false_type;
|
||||
|
||||
template <class T> struct is_pointer : false_type {};
|
||||
template <class T> struct is_pointer<T*> : true_type {};
|
||||
|
||||
template <class T, class U> struct is_same : public false_type {};
|
||||
template <class T> struct is_same<T, T> : true_type {};
|
||||
|
||||
template<class> struct is_array : public false_type {};
|
||||
template<class T, size_t n> struct is_array<T[n]> : public true_type {};
|
||||
template<class T> struct is_array<T[]> : public true_type {};
|
||||
|
||||
template <class T> struct is_non_const_reference : false_type {};
|
||||
template <class T> struct is_non_const_reference<T&> : true_type {};
|
||||
template <class T> struct is_non_const_reference<const T&> : false_type {};
|
||||
|
||||
template <class T> struct is_void : false_type {};
|
||||
template <> struct is_void<void> : true_type {};
|
||||
|
||||
namespace internal {
|
||||
|
||||
// Types YesType and NoType are guaranteed such that sizeof(YesType) <
|
||||
// sizeof(NoType).
|
||||
typedef char YesType;
|
||||
|
||||
struct NoType {
|
||||
YesType dummy[2];
|
||||
};
|
||||
|
||||
// This class is an implementation detail for is_convertible, and you
|
||||
// don't need to know how it works to use is_convertible. For those
|
||||
// who care: we declare two different functions, one whose argument is
|
||||
// of type To and one with a variadic argument list. We give them
|
||||
// return types of different size, so we can use sizeof to trick the
|
||||
// compiler into telling us which function it would have chosen if we
|
||||
// had called it with an argument of type From. See Alexandrescu's
|
||||
// _Modern C++ Design_ for more details on this sort of trick.
|
||||
|
||||
struct ConvertHelper {
|
||||
template <typename To>
|
||||
static YesType Test(To);
|
||||
|
||||
template <typename To>
|
||||
static NoType Test(...);
|
||||
|
||||
template <typename From>
|
||||
static From& Create();
|
||||
};
|
||||
|
||||
// Used to determine if a type is a struct/union/class. Inspired by Boost's
|
||||
// is_class type_trait implementation.
|
||||
struct IsClassHelper {
|
||||
template <typename C>
|
||||
static YesType Test(void(C::*)(void));
|
||||
|
||||
template <typename C>
|
||||
static NoType Test(...);
|
||||
};
|
||||
|
||||
} // namespace internal
|
||||
|
||||
// Inherits from true_type if From is convertible to To, false_type otherwise.
|
||||
//
|
||||
// Note that if the type is convertible, this will be a true_type REGARDLESS
|
||||
// of whether or not the conversion would emit a warning.
|
||||
template <typename From, typename To>
|
||||
struct is_convertible
|
||||
: integral_constant<bool,
|
||||
sizeof(internal::ConvertHelper::Test<To>(
|
||||
internal::ConvertHelper::Create<From>())) ==
|
||||
sizeof(internal::YesType)> {
|
||||
};
|
||||
|
||||
template <typename T>
|
||||
struct is_class
|
||||
: integral_constant<bool,
|
||||
sizeof(internal::IsClassHelper::Test<T>(0)) ==
|
||||
sizeof(internal::YesType)> {
|
||||
};
|
||||
|
||||
} // namespace rtc
|
||||
|
||||
#endif // WEBRTC_BASE_TEMPLATE_UTIL_H_
|
Reference in New Issue
Block a user