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/* -*- 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 "SystemProperty.h"
#include <dlfcn.h>
#include <string.h>
#include "nsDebug.h"
#include "prinit.h"
namespace mozilla {
namespace system {
namespace {
typedef int (*PropertyGet)(const char*, char*, const char*);
typedef int (*PropertySet)(const char*, const char*);
static void *sLibcUtils;
static PRCallOnceType sInitLibcUtils;
static int
FakePropertyGet(const char* key, char* value, const char* default_value)
{
if(!default_value) {
value[0] = '\0';
return 0;
}
int len = strlen(default_value);
if (len >= Property::VALUE_MAX_LENGTH) {
len = Property::VALUE_MAX_LENGTH - 1;
}
memcpy(value, default_value, len);
value[len] = '\0';
return len;
}
static int
FakePropertySet(const char* key, const char* value)
{
return 0;
}
static PRStatus
InitLibcUtils()
{
sLibcUtils = dlopen("/system/lib/libcutils.so", RTLD_LAZY);
// We will fallback to the fake getter/setter when sLibcUtils is not valid.
return PR_SUCCESS;
}
static void*
GetLibcUtils()
{
PR_CallOnce(&sInitLibcUtils, InitLibcUtils);
return sLibcUtils;
}
} // anonymous namespace
/*static*/ int
Property::Get(const char* key, char* value, const char* default_value)
{
void *libcutils = GetLibcUtils();
if (libcutils) {
PropertyGet getter = (PropertyGet) dlsym(libcutils, "property_get");
if (getter) {
return getter(key, value, default_value);
}
NS_WARNING("Failed to get property_get() from libcutils!");
}
NS_WARNING("Fallback to the FakePropertyGet()");
return FakePropertyGet(key, value, default_value);
}
/*static*/ int
Property::Set(const char* key, const char* value)
{
void *libcutils = GetLibcUtils();
if (libcutils) {
PropertySet setter = (PropertySet) dlsym(libcutils, "property_set");
if (setter) {
return setter(key, value);
}
NS_WARNING("Failed to get property_set() from libcutils!");
}
NS_WARNING("Fallback to the FakePropertySet()");
return FakePropertySet(key, value);
}
} // namespace system
} // namespace mozilla
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