1 files changed, 122 insertions, 0 deletions
diff --git a/adb/sysdeps/env.cpp b/adb/sysdeps/env.cpp
new file mode 100644
index 000000000..40587280c
--- /dev/null
+++ b/adb/sysdeps/env.cpp
@@ -0,0 +1,122 @@
+/*
+ * Copyright (C) 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "sysdeps/env.h"
+
+#ifdef _WIN32
+#include <lmcons.h>
+#include <windows.h>
+#endif  // _WIN32
+
+#include <android-base/utf8.h>
+
+namespace adb {
+namespace sysdeps {
+
+std::optional<std::string> GetEnvironmentVariable(std::string_view var) {
+    if (var.empty()) {
+        return std::nullopt;
+    }
+
+#ifdef _WIN32
+    constexpr size_t kMaxEnvVarSize = 32767;
+    wchar_t wbuf[kMaxEnvVarSize];
+    std::wstring wvar;
+    if (!android::base::UTF8ToWide(var.data(), &wvar)) {
+        return std::nullopt;
+    }
+
+    auto sz = ::GetEnvironmentVariableW(wvar.data(), wbuf, sizeof(wbuf));
+    if (sz == 0) {
+        return std::nullopt;
+    }
+
+    std::string val;
+    if (!android::base::WideToUTF8(wbuf, &val)) {
+        return std::nullopt;
+    }
+
+    return std::make_optional(val);
+#else  // !_WIN32
+    const char* val = getenv(var.data());
+    if (val == nullptr) {
+        return std::nullopt;
+    }
+
+    return std::make_optional(std::string(val));
+#endif
+}
+
+#ifdef _WIN32
+constexpr char kHostNameEnvVar[] = "COMPUTERNAME";
+constexpr char kUserNameEnvVar[] = "USERNAME";
+#else
+constexpr char kHostNameEnvVar[] = "HOSTNAME";
+constexpr char kUserNameEnvVar[] = "LOGNAME";
+#endif
+
+std::string GetHostNameUTF8() {
+    const auto hostName = GetEnvironmentVariable(kHostNameEnvVar);
+    if (hostName && !hostName->empty()) {
+        return *hostName;
+    }
+
+#ifdef _WIN32
+    wchar_t wbuf[MAX_COMPUTERNAME_LENGTH + 1];
+    DWORD size = sizeof(wbuf);
+    if (!GetComputerNameW(wbuf, &size) || size == 0) {
+        return "";
+    }
+
+    std::string name;
+    if (!android::base::WideToUTF8(wbuf, &name)) {
+        return "";
+    }
+
+    return name;
+#else   // !_WIN32
+    char buf[256];
+    return (gethostname(buf, sizeof(buf)) == -1) ? "" : buf;
+#endif  // _WIN32
+}
+
+std::string GetLoginNameUTF8() {
+    const auto userName = GetEnvironmentVariable(kUserNameEnvVar);
+    if (userName && !userName->empty()) {
+        return *userName;
+    }
+
+#ifdef _WIN32
+    wchar_t wbuf[UNLEN + 1];
+    DWORD size = sizeof(wbuf);
+    if (!GetUserNameW(wbuf, &size) || size == 0) {
+        return "";
+    }
+
+    std::string login;
+    if (!android::base::WideToUTF8(wbuf, &login)) {
+        return "";
+    }
+
+    return login;
+#else   // !_WIN32
+    const char* login = getlogin();
+    return login ? login : "";
+#endif  // _WIN32
+}
+
+}  // namespace sysdeps
+}  // namespace adb