hcid 分析

hcid分析实际上就是蓝牙启动流程的分析。

 

先看用法：hcid [-n] [-d] [-m mtu] [-f config file]

进入main()函数：

    1.hcid的一些默认设置，例如安全方式，名字等

init_defaults();

static inline void init_device_defaults(struct device_opts *device_opts)

{

memset(device_opts, 0, sizeof(*device_opts));

device_opts->scan = SCAN_PAGE;

device_opts->mode = MODE_CONNECTABLE;

device_opts->name = g_strdup("BlueZ");

device_opts->discovto = HCID_DEFAULT_DISCOVERABLE_TIMEOUT;

}

    2.分析命令行

while ((opt = getopt(argc, argv, "ndsm:xf:")) != EOF)

    3.运行于后台，设置权限，并设置信号

if (daemonize && daemon(0, 0)) 

umask(0077);

    4.创建并绑定hci socket

if ((hcid.sock = socket(AF_BLUETOOTH, SOCK_RAW, BTPROTO_HCI)) < 0) {

error("Can't open HCI socket: %s (%d)",

strerror(errno), errno);

exit(1);

}

if (bind(hcid.sock, (struct sockaddr *) &addr, sizeof(addr)) < 0) {

error("Can't bind HCI socket: %s (%d)",

strerror(errno), errno);

exit(1);

}

    5.设置过滤

hci_filter_clear(&flt);

hci_filter_set_ptype(HCI_EVENT_PKT, &flt);

hci_filter_set_event(EVT_STACK_INTERNAL, &flt);

if (setsockopt(hcid.sock, SOL_HCI, HCI_FILTER, &flt, sizeof(flt)) < 0) {

error("Can't set filter: %s (%d)",

strerror(errno), errno);

exit(1);

}

    6.下载main.conf

config = load_config(CONFIGDIR "/main.conf");

if (read_config(hcid.config_file) < 0)

error("Config load failed");

    7.添加IO通道

g_io_add_watch(child_io,

G_IO_IN | G_IO_ERR | G_IO_HUP | G_IO_NVAL,

child_exit, NULL);

    8.初始化适配器

init_adapters();

    9.初始化agent

agent_init();

    10.初始化dbus

if (hcid_dbus_init() < 0) {

error("Unable to get on D-Bus");

exit(1);

}

    11.开始sdp服务

start_sdp_server(mtu, hcid.deviceid, SDP_SERVER_COMPAT);

    12.初始化插件

plugin_init(config);

    13.初始化安全数据

init_security_data();

    14.初始化已连接的设备

init_all_devices(hcid.sock);

    15.恢复，清理

hcid_dbus_unregister();

plugin_cleanup();

stop_sdp_server();

free_device_opts();

agent_exit();

hcid_dbus_exit();