Android系统--Binder系统具体框架分析（一）补充
补充：对Binder驱动分析一的代码补充，添加saygoobye和saygoodbye_to服务
test_server.h
#ifndef _TEST_SERVER_H
#define _TEST_SERVER_H
#define HELLO_SVR_CMD_SAYHELLO 0
#define HELLO_SVR_CMD_SAYHELLO_TO 1
#define GOODBYE_SVR_CMD_SAYGOODBYE 0
#define GOODBYE_SVR_CMD_SAYGOODBYE_TO 1
#endif // _TEST_SERVER_H
test_server.c
/* Copyright 2008 The Android Open Source Project
*/
#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <linux/types.h>
#include<stdbool.h>
#include <string.h>
#include <private/android_filesystem_config.h>
#include "binder.h"
#include "test_server.h"
int svcmgr_publish(struct binder_state *bs, uint32_t target, const char *name, void *ptr)
{
int status;
unsigned iodata[512/4];
struct binder_io msg, reply;
bio_init(&msg, iodata, sizeof(iodata), 4); //分配binder_io结构体空间
bio_put_uint32(&msg, 0); // strict mode header
bio_put_string16_x(&msg, SVC_MGR_NAME);
bio_put_string16_x(&msg, name);
bio_put_obj(&msg, ptr); //构造结构体
if (binder_call(bs, &msg, &reply, target, SVC_MGR_ADD_SERVICE)) //添加注册Binder服务
return -1;
status = bio_get_uint32(&reply); //获得返回值
binder_done(bs, &msg, &reply); //结束标志
return status;
}
void sayhello(void)
{
static int cnt = 0;
fprintf(stderr, "say hello : %d\n", cnt++);
}
int sayhello_to(char *name)
{
static int cnt = 0;
fprintf(stderr, "say hello to %s : %d\n", name, cnt++);
return cnt;
}
void saygoodbye(void)
{
static int cnt = 0;
fprintf(stderr, "say goodbye : %d\n", cnt++);
}
int saygoodbye_to(char *name)
{
static int cnt = 0;
fprintf(stderr, "say goodbye to %s : %d\n", name, cnt++);
return cnt;
}
int hello_service_handler(struct binder_state *bs,
struct binder_transaction_data *txn,
struct binder_io *msg,
struct binder_io *reply)
{
/* 根据txn->code知道要调用哪一个函数
* 如果需要参数, 可以从msg取出
* 如果要返回结果, 可以把结果放入reply
*/
/* sayhello
* sayhello_to
*/
uint16_t *s;
char name[512];
size_t len;
uint32_t handle;
uint32_t strict_policy;
int i;
// Equivalent to Parcel::enforceInterface(), reading the RPC
// header with the strict mode policy mask and the interface name.
// Note that we ignore the strict_policy and don't propagate it
// further (since we do no outbound RPCs anyway).
strict_policy = bio_get_uint32(msg);
//获得处理函数标志，并调用处理函数
switch(txn->code) {
case HELLO_SVR_CMD_SAYHELLO:
sayhello();
return 0;
case HELLO_SVR_CMD_SAYHELLO_TO:
/* 从msg里取出字符串 */
s = bio_get_string16(msg, &len);
if (s == NULL) {
return -1;
}
for (i = 0; i < len; i++)
name[i] = s[i];
name[i] = '\0';
/* 处理 */
i = sayhello_to(name);
/* 把结果放入reply */
bio_put_uint32(reply, i);
break;
default:
fprintf(stderr, "unknown code %d\n", txn->code);
return -1;
}
return 0;
}
int goodbye_service_handler(struct binder_state *bs,
struct binder_transaction_data *txn,
struct binder_io *msg,
struct binder_io *reply)
{
/* 根据txn->code知道要调用哪一个函数
* 如果需要参数, 可以从msg取出
* 如果要返回结果, 可以把结果放入reply
*/
/* sayhello
* sayhello_to
*/
uint16_t *s;
char name[512];
size_t len;
uint32_t handle;
uint32_t strict_policy;
int i;
// Equivalent to Parcel::enforceInterface(), reading the RPC
// header with the strict mode policy mask and the interface name.
// Note that we ignore the strict_policy and don't propagate it
// further (since we do no outbound RPCs anyway).
strict_policy = bio_get_uint32(msg);
switch(txn->code) {
case GOODBYE_SVR_CMD_SAYGOODBYE:
saygoodbye();
return 0;
case GOODBYE_SVR_CMD_SAYGOODBYE_TO:
/* 从msg里取出字符串 */
s = bio_get_string16(msg, &len);
if (s == NULL) {
return -1;
}
for (i = 0; i < len; i++)
name[i] = s[i];
name[i] = '\0';
/* 处理 */
i = saygoodbye_to(name);
/* 把结果放入reply */
bio_put_uint32(reply, i);
break;
default:
fprintf(stderr, "unknown code %d\n", txn->code);
return -1;
}
return 0;
}
int test_server_handler(struct binder_state *bs,
struct binder_transaction_data *txn,
struct binder_io *msg,
struct binder_io *reply)
{
int (*handler)(struct binder_state *bs,
struct binder_transaction_data *txn,
struct binder_io *msg,
struct binder_io *reply); //构造处理方法
handler = (int (*)(struct binder_state *bs,
struct binder_transaction_data *txn,
struct binder_io *msg,
struct binder_io *reply))txn->target.ptr; //根据txn->target.ptr返回处理相应方法
return handler(bs, txn, msg, reply); //返回所调用的处理方法
}
int main(int argc, char **argv)
{
int fd;
struct binder_state *bs;
uint32_t svcmgr = BINDER_SERVICE_MANAGER;
uint32_t handle;
int ret;
bs = binder_open(128*1024); //打开Binder驱动设备
if (!bs) {
fprintf(stderr, "failed to open binder driver\n");
return -1;
}
/* add service */
ret = svcmgr_publish(bs, svcmgr, "hello", hello_service_handler); //注册
if (ret) {
fprintf(stderr, "failed to publish hello service\n");
return -1;
}
ret = svcmgr_publish(bs, svcmgr, "goodbye", goodbye_service_handler);
if (ret) {
fprintf(stderr, "failed to publish goodbye service\n");
}
#if 0
while (1)
{
/* read data */
/* parse data, and process */
/* reply */
}
#endif
binder_loop(bs, test_server_handler); //从队列中取出响应的处理函数
return 0;
}
server.c
/* Copyright 2008 The Android Open Source Project
*/
#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <linux/types.h>
#include<stdbool.h>
#include <string.h>
#include <private/android_filesystem_config.h>
#include "binder.h"
#include "test_server.h"
uint32_t svcmgr_lookup(struct binder_state *bs, uint32_t target, const char *name)
{
uint32_t handle;
unsigned iodata[512/4];
struct binder_io msg, reply;
bio_init(&msg, iodata, sizeof(iodata), 4);
bio_put_uint32(&msg, 0); // strict mode header
bio_put_string16_x(&msg, SVC_MGR_NAME);
bio_put_string16_x(&msg, name);
if (binder_call(bs, &msg, &reply, target, SVC_MGR_CHECK_SERVICE))
return 0;
handle = bio_get_ref(&reply);
if (handle)
binder_acquire(bs, handle);
binder_done(bs, &msg, &reply);
return handle;
}
struct binder_state *g_bs;
uint32_t g_hello_handle;
uint32_t g_goodbye_handle;
void sayhello(void)
{
unsigned iodata[512/4];
struct binder_io msg, reply;
/* 构造binder_io */
bio_init(&msg, iodata, sizeof(iodata), 4);
bio_put_uint32(&msg, 0); // strict mode header
/* 放入参数 */
/* 调用binder_call */
if (binder_call(g_bs, &msg, &reply, g_hello_handle, HELLO_SVR_CMD_SAYHELLO))
return ;
/* 从reply中解析出返回值 */
binder_done(g_bs, &msg, &reply);
}
int sayhello_to(char *name)
{
unsigned iodata[512/4];
struct binder_io msg, reply;
int ret;
/* 构造binder_io */
bio_init(&msg, iodata, sizeof(iodata), 4);
bio_put_uint32(&msg, 0); // strict mode header
/* 放入参数 */
bio_put_string16_x(&msg, name);
/* 调用binder_call */
if (binder_call(g_bs, &msg, &reply, g_hello_handle, HELLO_SVR_CMD_SAYHELLO_TO))
return 0;
/* 从reply中解析出返回值 */
ret = bio_get_uint32(&reply);
binder_done(g_bs, &msg, &reply);
return ret;
}
void saygoodbye(void)
{
unsigned iodata[512/4];
struct binder_io msg, reply;
/* 构造binder_io */
bio_init(&msg, iodata, sizeof(iodata), 4);
bio_put_uint32(&msg, 0); // strict mode header
/* 放入参数 */
/* 调用binder_call */
if (binder_call(g_bs, &msg, &reply, g_goodbye_handle, GOODBYE_SVR_CMD_SAYGOODBYE))
return ;
/* 从reply中解析出返回值 */
binder_done(g_bs, &msg, &reply);
}
int saygoodbye_to(char *name)
{
unsigned iodata[512/4];
struct binder_io msg, reply;
int ret;
/* 构造binder_io */
bio_init(&msg, iodata, sizeof(iodata), 4);
bio_put_uint32(&msg, 0); // strict mode header
/* 放入参数 */
bio_put_string16_x(&msg, name);
/* 调用binder_call */
if (binder_call(g_bs, &msg, &reply, g_goodbye_handle, GOODBYE_SVR_CMD_SAYGOODBYE_TO))
return 0;
/* 从reply中解析出返回值 */
ret = bio_get_uint32(&reply);
binder_done(g_bs, &msg, &reply);
return ret;
}
/* ./test_client hello
* ./test_client hello <name>
*/
int main(int argc, char **argv)
{
int fd;
struct binder_state *bs;
uint32_t svcmgr = BINDER_SERVICE_MANAGER;
uint32_t handle;
int ret;
if (argc < 2){
fprintf(stderr, "Usage:\n");
fprintf(stderr, "%s <hello|goodbye>\n", argv[0]);
fprintf(stderr, "%s <hello|goodbye> <name>\n", argv[0]);
return -1;
}
bs = binder_open(128*1024); //打开Binder驱动设备
if (!bs) {
fprintf(stderr, "failed to open binder driver\n");
return -1;
}
g_bs = bs;
/* get service */
handle = svcmgr_lookup(bs, svcmgr, "goodbye"); //查找获取服务的引用
if (!handle) {
fprintf(stderr, "failed to get goodbye service\n");
return -1;
}
g_goodbye_handle = handle;
fprintf(stderr, "Handle for goodbye service = %d\n", g_goodbye_handle);
handle = svcmgr_lookup(bs, svcmgr, "hello");
if (!handle) {
fprintf(stderr, "failed to get hello service\n");
return -1;
}
g_hello_handle = handle;
fprintf(stderr, "Handle for hello service = %d\n", g_hello_handle);
/* send data to server */
if (!strcmp(argv[1], "hello"))
{
if (argc == 2) {
sayhello();
} else if (argc == 3) {
ret = sayhello_to(argv[2]);
fprintf(stderr, "get ret of sayhello_to = %d\n", ret);
}
} else if (!strcmp(argv[1], "goodbye"))
{
if (argc == 2) {
saygoodbye();
} else if (argc == 3) {
ret = saygoodbye_to(argv[2]);
fprintf(stderr, "get ret of sayhello_to = %d\n", ret);
}
}
binder_release(bs, handle); //释放binder_acquire(bs, handle);
return 0;
}
