Repo created

TMessagesProj/jni/voip/webrtc/rtc_base/string_utils.h

@@ -0,0 +1,138 @@
+/*
+ *  Copyright 2004 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.
+ */
+
+#ifndef RTC_BASE_STRING_UTILS_H_
+#define RTC_BASE_STRING_UTILS_H_
+
+#include <stdio.h>
+#include <string.h>
+
+#include "absl/strings/string_view.h"
+
+#if defined(WEBRTC_WIN)
+#include <malloc.h>
+#include <wchar.h>
+#include <windows.h>
+
+#endif  // WEBRTC_WIN
+
+#if defined(WEBRTC_POSIX)
+#include <stdlib.h>
+#include <strings.h>
+#endif  // WEBRTC_POSIX
+
+#include <string>
+
+#include "absl/strings/string_view.h"
+
+namespace rtc {
+
+const size_t SIZE_UNKNOWN = static_cast<size_t>(-1);
+
+// An absl::string_view comparator functor for use with container types such as
+// std::map that support heterogenous lookup.
+//
+// Example usage:
+// std::map<std::string, int, rtc::AbslStringViewCmp> my_map;
+struct AbslStringViewCmp {
+  using is_transparent = void;
+  bool operator()(absl::string_view a, absl::string_view b) const {
+    return a < b;
+  }
+};
+
+// Safe version of strncpy that always nul-terminate.
+size_t strcpyn(char* buffer, size_t buflen, absl::string_view source);
+
+///////////////////////////////////////////////////////////////////////////////
+// UTF helpers (Windows only)
+///////////////////////////////////////////////////////////////////////////////
+
+#if defined(WEBRTC_WIN)
+
+inline std::wstring ToUtf16(const char* utf8, size_t len) {
+  if (len == 0)
+    return std::wstring();
+  int len16 = ::MultiByteToWideChar(CP_UTF8, 0, utf8, static_cast<int>(len),
+                                    nullptr, 0);
+  std::wstring ws(len16, 0);
+  ::MultiByteToWideChar(CP_UTF8, 0, utf8, static_cast<int>(len), &*ws.begin(),
+                        len16);
+  return ws;
+}
+
+inline std::wstring ToUtf16(absl::string_view str) {
+  return ToUtf16(str.data(), str.length());
+}
+
+inline std::string ToUtf8(const wchar_t* wide, size_t len) {
+  if (len == 0)
+    return std::string();
+  int len8 = ::WideCharToMultiByte(CP_UTF8, 0, wide, static_cast<int>(len),
+                                   nullptr, 0, nullptr, nullptr);
+  std::string ns(len8, 0);
+  ::WideCharToMultiByte(CP_UTF8, 0, wide, static_cast<int>(len), &*ns.begin(),
+                        len8, nullptr, nullptr);
+  return ns;
+}
+
+inline std::string ToUtf8(const wchar_t* wide) {
+  return ToUtf8(wide, wcslen(wide));
+}
+
+inline std::string ToUtf8(const std::wstring& wstr) {
+  return ToUtf8(wstr.data(), wstr.length());
+}
+
+#endif  // WEBRTC_WIN
+
+// TODO(jonasolsson): replace with absl::Hex when that becomes available.
+std::string ToHex(int i);
+
+// CompileTimeString comprises of a string-like object which can be used as a
+// regular const char* in compile time and supports concatenation. Useful for
+// concatenating constexpr strings in for example macro declarations.
+namespace rtc_base_string_utils_internal {
+template <int NPlus1>
+struct CompileTimeString {
+  char string[NPlus1] = {0};
+  constexpr CompileTimeString() = default;
+  template <int MPlus1>
+  explicit constexpr CompileTimeString(const char (&chars)[MPlus1]) {
+    char* chars_pointer = string;
+    for (auto c : chars)
+      *chars_pointer++ = c;
+  }
+  template <int MPlus1>
+  constexpr auto Concat(CompileTimeString<MPlus1> b) {
+    CompileTimeString<NPlus1 + MPlus1 - 1> result;
+    char* chars_pointer = result.string;
+    for (auto c : string)
+      *chars_pointer++ = c;
+    chars_pointer = result.string + NPlus1 - 1;
+    for (auto c : b.string)
+      *chars_pointer++ = c;
+    result.string[NPlus1 + MPlus1 - 2] = 0;
+    return result;
+  }
+  constexpr operator const char*() { return string; }
+};
+}  // namespace rtc_base_string_utils_internal
+
+// Makes a constexpr CompileTimeString<X> without having to specify X
+// explicitly.
+template <int N>
+constexpr auto MakeCompileTimeString(const char (&a)[N]) {
+  return rtc_base_string_utils_internal::CompileTimeString<N>(a);
+}
+
+}  // namespace rtc
+
+#endif  // RTC_BASE_STRING_UTILS_H_