1 files changed, 136 insertions, 0 deletions
diff --git a/xpcom/threads/nsEnvironment.cpp b/xpcom/threads/nsEnvironment.cpp
new file mode 100644
index 0000000000..54efd9194a
--- /dev/null
+++ b/xpcom/threads/nsEnvironment.cpp
@@ -0,0 +1,136 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "nsEnvironment.h"
+#include "prenv.h"
+#include "nsBaseHashtable.h"
+#include "nsHashKeys.h"
+#include "nsPromiseFlatString.h"
+#include "nsDependentString.h"
+#include "nsNativeCharsetUtils.h"
+#include "mozilla/Printf.h"
+#include "mozilla/StaticMutex.h"
+
+using namespace mozilla;
+
+NS_IMPL_ISUPPORTS(nsEnvironment, nsIEnvironment)
+
+nsresult nsEnvironment::Create(REFNSIID aIID, void** aResult) {
+  nsresult rv;
+  *aResult = nullptr;
+
+  nsEnvironment* obj = new nsEnvironment();
+
+  rv = obj->QueryInterface(aIID, aResult);
+  if (NS_FAILED(rv)) {
+    delete obj;
+  }
+  return rv;
+}
+
+NS_IMETHODIMP
+nsEnvironment::Exists(const nsAString& aName, bool* aOutValue) {
+  nsAutoCString nativeName;
+  nsresult rv = NS_CopyUnicodeToNative(aName, nativeName);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  nsAutoCString nativeVal;
+#if defined(XP_UNIX)
+  /* For Unix/Linux platforms we follow the Unix definition:
+   * An environment variable exists when |getenv()| returns a non-nullptr
+   * value. An environment variable does not exist when |getenv()| returns
+   * nullptr.
+   */
+  const char* value = PR_GetEnv(nativeName.get());
+  *aOutValue = value && *value;
+#else
+  /* For non-Unix/Linux platforms we have to fall back to a
+   * "portable" definition (which is incorrect for Unix/Linux!!!!)
+   * which simply checks whether the string returned by |Get()| is empty
+   * or not.
+   */
+  nsAutoString value;
+  Get(aName, value);
+  *aOutValue = !value.IsEmpty();
+#endif /* XP_UNIX */
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsEnvironment::Get(const nsAString& aName, nsAString& aOutValue) {
+  nsAutoCString nativeName;
+  nsresult rv = NS_CopyUnicodeToNative(aName, nativeName);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  nsAutoCString nativeVal;
+  const char* value = PR_GetEnv(nativeName.get());
+  if (value && *value) {
+    rv = NS_CopyNativeToUnicode(nsDependentCString(value), aOutValue);
+  } else {
+    aOutValue.Truncate();
+    rv = NS_OK;
+  }
+
+  return rv;
+}
+
+/* Environment strings must have static duration; We're gonna leak all of this
+ * at shutdown: this is by design, caused how Unix/Linux implement environment
+ * vars.
+ */
+
+typedef nsBaseHashtableET<nsCharPtrHashKey, char*> EnvEntryType;
+typedef nsTHashtable<EnvEntryType> EnvHashType;
+
+static StaticMutex gEnvHashMutex;
+static EnvHashType* gEnvHash MOZ_GUARDED_BY(gEnvHashMutex) = nullptr;
+
+static EnvHashType* EnsureEnvHash() MOZ_REQUIRES(gEnvHashMutex) {
+  if (!gEnvHash) {
+    gEnvHash = new EnvHashType;
+  }
+  return gEnvHash;
+}
+
+NS_IMETHODIMP
+nsEnvironment::Set(const nsAString& aName, const nsAString& aValue) {
+  nsAutoCString nativeName;
+  nsAutoCString nativeVal;
+
+  nsresult rv = NS_CopyUnicodeToNative(aName, nativeName);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  rv = NS_CopyUnicodeToNative(aValue, nativeVal);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return rv;
+  }
+
+  StaticMutexAutoLock lock(gEnvHashMutex);
+  EnvEntryType* entry = EnsureEnvHash()->PutEntry(nativeName.get());
+  if (!entry) {
+    return NS_ERROR_OUT_OF_MEMORY;
+  }
+
+  SmprintfPointer newData =
+      mozilla::Smprintf("%s=%s", nativeName.get(), nativeVal.get());
+  if (!newData) {
+    return NS_ERROR_OUT_OF_MEMORY;
+  }
+
+  PR_SetEnv(newData.get());
+  if (entry->GetData()) {
+    free(entry->GetData());
+  }
+  entry->SetData(newData.release());
+  return NS_OK;
+}