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-rw-r--r--libcutils/properties.c368
1 files changed, 368 insertions, 0 deletions
diff --git a/libcutils/properties.c b/libcutils/properties.c
new file mode 100644
index 000000000..547cc6dc5
--- /dev/null
+++ b/libcutils/properties.c
@@ -0,0 +1,368 @@
+/*
+ * 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>
+
+static int send_prop_msg(prop_msg *msg)
+{
+ int s;
+ int r;
+
+ s = socket_local_client(PROP_SERVICE_NAME,
+ ANDROID_SOCKET_NAMESPACE_RESERVED,
+ SOCK_STREAM);
+ if(s < 0) return -1;
+
+ while((r = send(s, msg, sizeof(prop_msg), 0)) < 0) {
+ if((errno == EINTR) || (errno == EAGAIN)) continue;
+ break;
+ }
+
+ if(r == sizeof(prop_msg)) {
+ r = 0;
+ } else {
+ r = -1;
+ }
+
+ close(s);
+ return r;
+}
+
+int property_set(const char *key, const char *value)
+{
+ prop_msg msg;
+ unsigned resp;
+
+ if(key == 0) return -1;
+ if(value == 0) value = "";
+
+ if(strlen(key) >= PROP_NAME_MAX) return -1;
+ if(strlen(value) >= PROP_VALUE_MAX) return -1;
+
+ msg.cmd = PROP_MSG_SETPROP;
+ strcpy((char*) msg.name, key);
+ strcpy((char*) msg.value, value);
+
+ return send_prop_msg(&msg);
+}
+
+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) {
+ LOGW("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
+ //LOGW("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) {
+ //LOGW("not connected to system property server\n");
+ } else {
+ //LOGV("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;
+
+ //LOGV("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 {
+ LOGE("Got strange response to property_get request (%d)\n",
+ recvBuf[0]);
+ assert(0);
+ return -1;
+ }
+ //LOGV("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;
+
+ //LOGV("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)
+{
+ //LOGV("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
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