/*
* Copyright (C) 2006 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.
*/
#define LOG_TAG "properties"
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <cutils/sockets.h>
#include <errno.h>
#include <assert.h>
#include <cutils/properties.h>
#include "loghack.h"
#ifdef HAVE_LIBC_SYSTEM_PROPERTIES
#define _REALLY_INCLUDE_SYS__SYSTEM_PROPERTIES_H_
#include <sys/_system_properties.h>
int property_set(const char *key, const char *value)
{
return __system_property_set(key, value);
}
int property_get(const char *key, char *value, const char *default_value)
{
int len;
len = __system_property_get(key, value);
if(len > 0) {
return len;
}
if(default_value) {
len = strlen(default_value);
memcpy(value, default_value, len + 1);
}
return len;
}
int property_list(void (*propfn)(const char *key, const char *value, void *cookie),
void *cookie)
{
char name[PROP_NAME_MAX];
char value[PROP_VALUE_MAX];
const prop_info *pi;
unsigned n;
for(n = 0; (pi = __system_property_find_nth(n)); n++) {
__system_property_read(pi, name, value);
propfn(name, value, cookie);
}
return 0;
}
#elif defined(HAVE_SYSTEM_PROPERTY_SERVER)
/*
* The Linux simulator provides a "system property server" that uses IPC
* to set/get/list properties. The file descriptor is shared by all
* threads in the process, so we use a mutex to ensure that requests
* from multiple threads don't get interleaved.
*/
#include <stdio.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <pthread.h>
static pthread_once_t gInitOnce = PTHREAD_ONCE_INIT;
static pthread_mutex_t gPropertyFdLock = PTHREAD_MUTEX_INITIALIZER;
static int gPropFd = -1;
/*
* Connect to the properties server.
*
* Returns the socket descriptor on success.
*/
static int connectToServer(const char* fileName)
{
int sock = -1;
int cc;
struct sockaddr_un addr;
sock = socket(AF_UNIX, SOCK_STREAM, 0);
if (sock < 0) {
ALOGW("UNIX domain socket create failed (errno=%d)\n", errno);
return -1;
}
/* connect to socket; fails if file doesn't exist */
strcpy(addr.sun_path, fileName); // max 108 bytes
addr.sun_family = AF_UNIX;
cc = connect(sock, (struct sockaddr*) &addr, SUN_LEN(&addr));
if (cc < 0) {
// ENOENT means socket file doesn't exist
// ECONNREFUSED means socket exists but nobody is listening
//ALOGW("AF_UNIX connect failed for '%s': %s\n",
// fileName, strerror(errno));
close(sock);
return -1;
}
return sock;
}
/*
* Perform one-time initialization.
*/
static void init(void)
{
assert(gPropFd == -1);
gPropFd = connectToServer(SYSTEM_PROPERTY_PIPE_NAME);
if (gPropFd < 0) {
//ALOGW("not connected to system property server\n");
} else {
//ALOGV("Connected to system property server\n");
}
}
int property_get(const char *key, char *value, const char *default_value)
{
char sendBuf[1+PROPERTY_KEY_MAX];
char recvBuf[1+PROPERTY_VALUE_MAX];
int len = -1;
//ALOGV("PROPERTY GET [%s]\n", key);
pthread_once(&gInitOnce, init);
if (gPropFd < 0) {
/* this mimics the behavior of the device implementation */
if (default_value != NULL) {
strcpy(value, default_value);
len = strlen(value);
}
return len;
}
if (strlen(key) >= PROPERTY_KEY_MAX) return -1;
memset(sendBuf, 0xdd, sizeof(sendBuf)); // placate valgrind
sendBuf[0] = (char) kSystemPropertyGet;
strcpy(sendBuf+1, key);
pthread_mutex_lock(&gPropertyFdLock);
if (write(gPropFd, sendBuf, sizeof(sendBuf)) != sizeof(sendBuf)) {
pthread_mutex_unlock(&gPropertyFdLock);
return -1;
}
if (read(gPropFd, recvBuf, sizeof(recvBuf)) != sizeof(recvBuf)) {
pthread_mutex_unlock(&gPropertyFdLock);
return -1;
}
pthread_mutex_unlock(&gPropertyFdLock);
/* first byte is 0 if value not defined, 1 if found */
if (recvBuf[0] == 0) {
if (default_value != NULL) {
strcpy(value, default_value);
len = strlen(value);
} else {
/*
* If the value isn't defined, hand back an empty string and
* a zero length, rather than a failure. This seems wrong,
* since you can't tell the difference between "undefined" and
* "defined but empty", but it's what the device does.
*/
value[0] = '\0';
len = 0;
}
} else if (recvBuf[0] == 1) {
strcpy(value, recvBuf+1);
len = strlen(value);
} else {
ALOGE("Got strange response to property_get request (%d)\n",
recvBuf[0]);
assert(0);
return -1;
}
//ALOGV("PROP [found=%d def='%s'] (%d) [%s]: [%s]\n",
// recvBuf[0], default_value, len, key, value);
return len;
}
int property_set(const char *key, const char *value)
{
char sendBuf[1+PROPERTY_KEY_MAX+PROPERTY_VALUE_MAX];
char recvBuf[1];
int result = -1;
//ALOGV("PROPERTY SET [%s]: [%s]\n", key, value);
pthread_once(&gInitOnce, init);
if (gPropFd < 0)
return -1;
if (strlen(key) >= PROPERTY_KEY_MAX) return -1;
if (strlen(value) >= PROPERTY_VALUE_MAX) return -1;
memset(sendBuf, 0xdd, sizeof(sendBuf)); // placate valgrind
sendBuf[0] = (char) kSystemPropertySet;
strcpy(sendBuf+1, key);
strcpy(sendBuf+1+PROPERTY_KEY_MAX, value);
pthread_mutex_lock(&gPropertyFdLock);
if (write(gPropFd, sendBuf, sizeof(sendBuf)) != sizeof(sendBuf)) {
pthread_mutex_unlock(&gPropertyFdLock);
return -1;
}
if (read(gPropFd, recvBuf, sizeof(recvBuf)) != sizeof(recvBuf)) {
pthread_mutex_unlock(&gPropertyFdLock);
return -1;
}
pthread_mutex_unlock(&gPropertyFdLock);
if (recvBuf[0] != 1)
return -1;
return 0;
}
int property_list(void (*propfn)(const char *key, const char *value, void *cookie),
void *cookie)
{
//ALOGV("PROPERTY LIST\n");
pthread_once(&gInitOnce, init);
if (gPropFd < 0)
return -1;
return 0;
}
#else
/* SUPER-cheesy place-holder implementation for Win32 */
#include <cutils/threads.h>
static mutex_t env_lock = MUTEX_INITIALIZER;
int property_get(const char *key, char *value, const char *default_value)
{
char ename[PROPERTY_KEY_MAX + 6];
char *p;
int len;
len = strlen(key);
if(len >= PROPERTY_KEY_MAX) return -1;
memcpy(ename, "PROP_", 5);
memcpy(ename + 5, key, len + 1);
mutex_lock(&env_lock);
p = getenv(ename);
if(p == 0) p = "";
len = strlen(p);
if(len >= PROPERTY_VALUE_MAX) {
len = PROPERTY_VALUE_MAX - 1;
}
if((len == 0) && default_value) {
len = strlen(default_value);
memcpy(value, default_value, len + 1);
} else {
memcpy(value, p, len);
value[len] = 0;
}
mutex_unlock(&env_lock);
return len;
}
int property_set(const char *key, const char *value)
{
char ename[PROPERTY_KEY_MAX + 6];
char *p;
int len;
int r;
if(strlen(value) >= PROPERTY_VALUE_MAX) return -1;
len = strlen(key);
if(len >= PROPERTY_KEY_MAX) return -1;
memcpy(ename, "PROP_", 5);
memcpy(ename + 5, key, len + 1);
mutex_lock(&env_lock);
#ifdef HAVE_MS_C_RUNTIME
{
char temp[256];
snprintf( temp, sizeof(temp), "%s=%s", ename, value);
putenv(temp);
r = 0;
}
#else
r = setenv(ename, value, 1);
#endif
mutex_unlock(&env_lock);
return r;
}
int property_list(void (*propfn)(const char *key, const char *value, void *cookie),
void *cookie)
{
return 0;
}
#endif