/* -*- 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"

using namespace mozilla;

NS_IMPL_ISUPPORTS(nsEnvironment, nsIEnvironment)

nsresult

nsEnvironment::Create(nsISupports* aOuter, REFNSIID aIID, void** aResult)

{

  nsresult rv;

  *aResult = nullptr;

  if (aOuter) {

    return NS_ERROR_NO_AGGREGATION;

  }

  nsEnvironment* obj = new nsEnvironment();

  rv = obj->QueryInterface(aIID, aResult);

  if (NS_FAILED(rv)) {

    delete obj;

  }

  return rv;

}

nsEnvironment::~nsEnvironment()

{

}

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 EnvHashType* gEnvHash = nullptr;

static bool

EnsureEnvHash()

{

  if (gEnvHash) {

    return true;

  }

  gEnvHash = new EnvHashType;

  if (!gEnvHash) {

    return false;

  }

  return true;

}

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;

  }

  MutexAutoLock lock(mLock);

  if (!EnsureEnvHash()) {

    return NS_ERROR_UNEXPECTED;

  }

  EnvEntryType* entry = gEnvHash->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->mData) {

    free(entry->mData);

  }

  entry->mData = newData.release();

  return NS_OK;

}