gecko-dev/xpcom/threads/nsEnvironment.cpp

164 строки
3.7 KiB
C++

/* -*- 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;
}
char* newData = mozilla::Smprintf("%s=%s",
nativeName.get(),
nativeVal.get());
if (!newData) {
return NS_ERROR_OUT_OF_MEMORY;
}
PR_SetEnv(newData);
if (entry->mData) {
mozilla::SmprintfFree(entry->mData);
}
entry->mData = newData;
return NS_OK;
}