学习目标

  • 能够调用AP模式的API实现网络连接
  • 能够调用STA模式的API实现网络连接
  • 能够自定义子系统

    学习内容

    子系统服务构建

    开发中，我们需要构建一些功能执行的底座，提供给其他的调用者使用。
    例如，wifi功能在我们的开发板中是一个功能服务，只要想上网的都需要使用他。
    我们可以把wifi功能加入到自己开发板中来。

    开发流程

  1. 在开发板目录下新建一个文件夹services。我的开发板目录为device/board/itcast/genkipi。
  2. 在services目录下新建BUILD.gn文件，并且配置这个BUILD.gn文件。
  3. 在services目录下新建wifi目录，并且在wifi目录新建BUILD.gn文件。
  4. 修改vendor/itcast/genkipi目录下的BUILD.gn。

    代码部分

    1. static_library("genkipi_wifi") {
    2. sources = [ 
    3.  "src/wifi_ap.c",
    4.  "src/wifi_sta.c"
    5. ]
    6. include_dirs = [
    7.  "include",
    8.   "//foundation/communication/wifi_lite/interfaces/wifiservice",
    9. ]
    10. }
    ```c

    ifndef WIFI_AP_H

    define WIFI_AP_H

include

/**

  • start wifi ap
  • @param ssid
  • @param password
  • @return 0 success / int wifi_ap_start(const char ssid, const char* password);

/**

  • stop wifi ap
  • @return 0 success */ int wifi_ap_stop(void);

endif //WIFI_AP_H

  1. ```c
  2. #ifndef __WIFI_STA_H__
  3. #define __WIFI_STA_H__
  5. /**
  6.  * link wifi
  7.  * @param ssid
  8.  * @param password
  9.  * @param hostname
  10.  * @return 0 success
  11.  */
  12. int wifi_sta_connect(const char* ssid, const char* password, const char* hostname);
  13. /**
  14.  * disconnect wifi
  15.  * @return 0 success
  16.  */
  17. int wifi_sta_disconnect(void);
  19. #endif //__WIFI_STA_H__
  1. #include "wifi_ap.h"
  3. #include "wifi_hotspot.h"
  4. #include "cmsis_os2.h"
  5. #include "lwip/netifapi.h"
  6. #include <string.h>
  8. static struct netif *g_iface = NULL;
  9. static volatile int g_hotspotStarted = 0;
  10. static volatile int g_joinedStations = 0;
  12. static char *wifi_ssid = NULL;
  14. static void OnHotspotStateChanged(int state) {
  15.     printf("[Debug]OnHotspotStateChanged: %d.\r\n", state);
  16.     if (state == WIFI_HOTSPOT_ACTIVE) {
  17.         g_hotspotStarted = 1;
  18.     } else {
  19.         g_hotspotStarted = 0;
  20.     }
  21. }
  23. static void OnHotspotStaJoin(StationInfo *info) {
  24.     g_joinedStations++;
  25.     printf("[Debug]+OnHotspotStaJoin: active stations = %d.\r\n", g_joinedStations);
  26. }
  28. static void OnHotspotStaLeave(StationInfo *info) {
  29.     g_joinedStations--;
  30.     printf("[Debug]-OnHotspotStaLeave: active stations = %d.\r\n", g_joinedStations);
  31. }
  33. WifiEvent g_defaultWifiEventListener = {
  34.         .OnHotspotStaJoin = OnHotspotStaJoin,
  35.         .OnHotspotStaLeave = OnHotspotStaLeave,
  36.         .OnHotspotStateChanged = OnHotspotStateChanged,
  37. };
  39. int wifi_ap_start(const char *ssid, const char *password) {
  40.     WifiErrorCode err_code = WIFI_SUCCESS;
  42.     err_code = RegisterWifiEvent(&g_defaultWifiEventListener);
  43.     printf("[Debug]RegisterWifiEvent:%d\r\n", err_code);
  45.     int len = strlen(ssid);
  46.     wifi_ssid = (char *) calloc(len + 1, sizeof(char));
  47.     memcpy(wifi_ssid, ssid, len);
  48.     wifi_ssid[len] = '\0';
  50.     HotspotConfig config = {0};
  51.     strcpy(config.ssid, ssid);
  52.     strcpy(config.preSharedKey, password);
  53.     config.securityType = WIFI_SEC_TYPE_PSK;
  54.     config.band = HOTSPOT_BAND_TYPE_2G;
  55.     config.channelNum = 7;
  57.     err_code = SetHotspotConfig(&config);
  58.     printf("[Debug]SetHotspotConfig:%d\r\n", err_code);
  60.     g_hotspotStarted = 0;
  61.     err_code = EnableHotspot();
  62.     printf("[Debug]EnableHotspot: %d\r\n", err_code);
  64.     while (!g_hotspotStarted) {
  65.         osDelay(10);
  66.     }
  68.     printf("[Debug]g_hotspotStarted = %d.\r\n", g_hotspotStarted);
  70.     g_iface = netifapi_netif_find("ap0");
  71.     if (g_iface) {
  72.         ip4_addr_t ipaddr, gateway, netmask;
  74.         IP4_ADDR(&ipaddr, 192, 168, 10, 1);
  75.         IP4_ADDR(&gateway, 192, 168, 10, 1);
  76.         IP4_ADDR(&netmask, 255, 255, 255, 0);
  77.         err_t ret = netifapi_netif_set_addr(g_iface, &ipaddr, &netmask, &gateway);
  78.         printf("[Debug]netifapi_netif_set_addr: %d\r\n", ret);
  80.         netifapi_dhcps_start(g_iface, 0, 0);
  81.     }
  82.     return err_code;
  83. }
  85. int wifi_ap_stop(void) {
  86.     if (g_iface) {
  87.         err_t ret = netifapi_dhcps_stop(g_iface);
  88.         printf("[Debug]netifapi_dhcps_stop: %d\r\n", ret);
  89.     }
  91.     WifiErrorCode err_code = UnRegisterWifiEvent(&g_defaultWifiEventListener);
  92.     printf("[Debug]UnRegisterWifiEvent: %d\r\n", err_code);
  94.     err_code = DisableHotspot();
  95.     printf("DisableHotspot: %d\r\n", err_code);
  96.     return err_code;
  97. }
  1. #include "wifi_sta.h"
  3. #include "ohos_init.h"
  4. #include "ohos_types.h"
  5. #include <stdio.h>
  6. #include <unistd.h>
  7. #include <string.h>
  8. #include "cmsis_os2.h"
  10. #include "wifi_device.h"
  11. #include "wifi_event.h"
  12. #include "wifi_error_code.h"
  14. #include "lwip/netif.h"
  15. #include "lwip/netifapi.h"
  16. #include "lwip/ip4_addr.h"
  17. #include "lwip/api_shell.h"
  20. #define DEF_TIMEOUT 15
  21. #define ONE_SECOND 1
  23. #define SELECT_WLAN_PORT "wlan0"
  25. static WifiEvent wifi_event_handler = {0};
  26. static int g_staScanSuccess = 0;
  27. static int g_ConnectSuccess = 0;
  28. static int ssid_count = 0;
  30. static struct netif *g_lwip_netif = NULL;
  31. static char *wifi_ssid = NULL;
  34. static unsigned char is_connected = 0;
  37. static void OnWifiConnectionChanged(int state, WifiLinkedInfo *info) {
  38.     (void) info;
  40.     if (state > 0) {
  41.         g_ConnectSuccess = 1;
  42.         printf("[wifi_sta]cb for wifi connect, success\r\n");
  43.     } else {
  44.         printf("[wifi_sta]cb for wifi connect, failed, please check password\r\n");
  45.     }
  46.     return;
  47. }
  49. static void OnWifiScanStateChanged(int state, int size) {
  50.     (void) state;
  51.     if (size > 0) {
  52.         ssid_count = size;
  53.         g_staScanSuccess = 1;
  54.     }
  55.     return;
  56. }
  58. static void OnHotspotStateChanged(int state) {
  59.     printf("[wifi_sta]cb for HotspotStateChanged:state is %d.\n", state);
  60.     return;
  61. }
  63. static void OnHotspotStaJoin(StationInfo *info) {
  64.     (void) info;
  65.     printf("[wifi_sta]STA join AP\r\n");
  66.     return;
  67. }
  69. static void OnHotspotStaLeave(StationInfo *info) {
  70.     (void) info;
  71.     printf("[wifi_sta]cb for HotspotStaLeave:mac is %s.\r\n", info->macAddress);
  72.     return;
  73. }
  75. static WifiErrorCode wifi_init(void) {
  76.     WifiErrorCode error;
  77.     wifi_event_handler.OnWifiConnectionChanged = OnWifiConnectionChanged;
  78.     wifi_event_handler.OnWifiScanStateChanged = OnWifiScanStateChanged;
  79.     wifi_event_handler.OnHotspotStateChanged = OnHotspotStateChanged;
  80.     wifi_event_handler.OnHotspotStaJoin = OnHotspotStaJoin;
  81.     wifi_event_handler.OnHotspotStaLeave = OnHotspotStaLeave;
  82.     error = RegisterWifiEvent(&wifi_event_handler);
  83.     return error;
  84. }
  86. static void wait_scan_result(void) {
  87.     int scanTimeout = DEF_TIMEOUT;
  88.     while (scanTimeout > 0) {
  89.         sleep(ONE_SECOND);
  90.         scanTimeout--;
  91.         if (g_staScanSuccess == 1) {
  92.             printf("[wifi_sta]wait scan result: wait success[%d]s\n", (DEF_TIMEOUT - scanTimeout));
  93.             break;
  94.         }
  95.     }
  96.     if (scanTimeout <= 0) {
  97.         printf("[wifi_sta]wait scan result:timeout!\n");
  98.     }
  99. }
  101. static int wait_connect_result(void) {
  102.     int ConnectTimeout = DEF_TIMEOUT;
  103.     while (ConnectTimeout > 0) {
  104.         sleep(1);
  105.         ConnectTimeout--;
  106.         if (g_ConnectSuccess == 1) {
  107.             printf("[wifi_sta]wait connect result:wait success[%d]s\n", (DEF_TIMEOUT - ConnectTimeout));
  108.             break;
  109.         }
  110.     }
  111.     if (ConnectTimeout <= 0) {
  112.         printf("[wifi_sta]wait connect result:timeout!\n");
  113.         return 0;
  114.     }
  115.     return 1;
  116. }
  118. int wifi_sta_connect(const char *ssid, const char *password, const char *hostname) {
  120.     // wifi init
  121.     WifiErrorCode error = wifi_init();
  122.     if (WIFI_SUCCESS != error) {
  123.         printf("[wifi_sta]register wifi event failed, error=%d\r\n", error);
  124.         return error;
  125.     }
  126.     printf("[wifi_sta]register wifi event success\r\n");
  128.     // wifi enable
  129.     error = EnableWifi();
  130.     if (WIFI_SUCCESS != error) {
  131.         printf("[wifi_sta]enable wifi  failed, error=%d\r\n", error);
  132.         return error;
  133.     }
  134.     printf("[wifi_sta]enable wifi success\r\n");
  136.     // check wifi active
  137.     if (IsWifiActive() == 0) {
  138.         printf("[wifi_sta] wifi station is not active\r\n");
  139.         return error;
  140.     }
  142.     int len = strlen(ssid);
  143.     wifi_ssid = (char *) calloc(len + 1, sizeof(char));
  144.     memcpy(wifi_ssid, ssid, len);
  145.     wifi_ssid[len] = '\0';
  147.     WifiDeviceConfig ap_config = {0};
  148.     strcpy(ap_config.ssid, ssid);
  149.     strcpy(ap_config.preSharedKey, password);
  150.     ap_config.securityType = WIFI_SEC_TYPE_PSK;
  152.     int result;
  153.     if (AddDeviceConfig(&ap_config, &result) == WIFI_SUCCESS) {
  155.         // connect to wifi
  156.         if (ConnectTo(result) == WIFI_SUCCESS && wait_connect_result() == 1) {
  157.             printf("[wifi_sta]wifi connect success!\r\n");
  158.             g_lwip_netif = netifapi_netif_find(SELECT_WLAN_PORT);
  159.         }
  160.     }
  162.     if (!g_lwip_netif) {
  163.         printf("[wifi_sta]netif error \r\n");
  164.         return -1;
  165.     }
  167.     // start dhcp
  168.     netifapi_set_hostname(g_lwip_netif, hostname, strlen(hostname));
  169.     netifapi_dhcp_start(g_lwip_netif);
  171.     // wait dhcp
  172.     while (1) {
  173.         if (dhcp_is_bound(g_lwip_netif) == ERR_OK) {
  174.             printf("[wifi_sta]dhcp bound success\r\n");
  176.             netifapi_netif_common(g_lwip_netif, dhcp_clients_info_show, NULL);
  177.             break;
  178.         }
  180.         osDelay(100);
  181.     }
  182.     is_connected = 1;
  183.     return WIFI_SUCCESS;
  184. }
  186. int wifi_sta_disconnect(void) {
  187.     if (!g_lwip_netif) {
  188.         printf("[wifi_sta]netif error \r\n");
  189.         return -1;
  190.     }
  192.     WifiErrorCode error = Disconnect();
  193.     if (WIFI_SUCCESS != error) {
  194.         printf("[wifi_sta]disconnect wifi failed, error=%d\r\n", error);
  195.         return error;
  196.     }
  198.     error = DisableWifi();
  199.     if (WIFI_SUCCESS != error) {
  200.         printf("[wifi_sta]disable wifi failed, error=%d\r\n", error);
  201.         return error;
  202.     }
  204.     error = UnRegisterWifiEvent(&wifi_event_handler);
  205.     if (WIFI_SUCCESS != error) {
  206.         printf("[wifi_sta]unregister wifi event failed, error=%d\r\n", error);
  207.         return error;
  208.     }
  209.     printf("[wifi_sta]disconnect wifi success\r\n");
  210.     is_connected = 0;
  211.     return WIFI_SUCCESS;
  212. }
  214. static int get_wifi_local_ip() {
  215.     if (!g_lwip_netif) {
  216.         printf("[wifi_sta]netif error \r\n");
  217.         return -1;
  218.     }
  220.     ip4_addr_t ip_addr;
  221.     ip4_addr_t netmask_addr;
  222.     ip4_addr_t gw_addr;
  223.     if (netifapi_netif_get_addr(g_lwip_netif, &ip_addr, &netmask_addr, &gw_addr) == ERR_OK) {
  224.         u32_t ip = ip_addr.addr;
  225.         u32_t netmask = netmask_addr.addr;
  226.         u32_t gw = gw_addr.addr;
  228.         printf("ip %d.%d.%d.%d\n\r", (ip & 0xff), ((ip >> 8) & 0xff), ((ip >> 16) & 0xff), (ip >> 24));
  229.         printf("netmask %d.%d.%d.%d\n\r", (netmask & 0xff), ((netmask >> 8) & 0xff), ((netmask >> 16) & 0xff),
  230.                (netmask >> 24));
  231.         printf("gw %d.%d.%d.%d\n\r", (gw & 0xff), ((gw >> 8) & 0xff), ((gw >> 16) & 0xff), (gw >> 24));
  232.     } else {
  233.         printf("netif get addr failed\r\n");
  234.     }
  236.     return 1;
  237. }
  1. group("genkipi_services") {
  2.     deps = [
  3.         "wifi:genkipi_wifi"
  4.     ]
  5. }
  1. # Copyright (C) 2020 Itcast Co., Ltd. All rights reserved.
  3. group("genkipi") {
  4.     deps = [
  5.        "//device/board/itcast/genkipi:run_genkipi_scons",
  6.        "//device/board/itcast/genkipi/app",
  7.        "//device/board/itcast/genkipi/iot_hardware_hals",
  8.        "//device/board/itcast/genkipi/services:genkipi_services"
  9.     ]
  10. }

配置说明

  1. vendor/itcast/genkipi/BUILD.gn描述了开发板提供的服务。deps表示编译依赖。 ```bash

    Copyright (C) 2020 Itcast Co., Ltd. All rights reserved.

group(“genkipi”) { deps = [ “//device/board/itcast/genkipi:run_genkipi_scons”, “//device/board/itcast/genkipi/app”, “//device/board/itcast/genkipi/iot_hardware_hals”, “//device/board/itcast/genkipi/services:genkipi_services” ] }

  2.    - `//device/board/itcast/genkipi/services:genkipi_services`指向了我们刚刚新建的文件夹`services`文件夹下的`BUILD.gn`文件。
  3. 2. `services/BUILD.gn`描述的是当前子系统服务的一些配置。
  4. ```bash
  5. group("genkipi_services") {
  6.     deps = [
  7.         "wifi:genkipi_wifi"
  8.     ]
  9. }
  • genkipi_services表示当前子服务名称。group表示是一个服务集合。
  • deps表示依赖。

  • wifi:genkipi_wifi表示当前services目录下的wifi目录中BUILD.gn配置

    1. services/wifi/BUILD.gn为wifi部分的配置。
      1. static_library("genkipi_wifi") {
      2. sources = [ 
      3. "src/wifi_ap.c",
      4. "src/wifi_sta.c"
      5. ]
      6. include_dirs = [
      7. "include",
      8. "//foundation/communication/wifi_lite/interfaces/wifiservice",
      9. ]
      10. }

  • sources表示源码部分

  • include_dirs表示需要引入的头

    AP逻辑说明

    AP就是扮演路由器角色，我们开启路由器，需要给路由器配置名称和密码，供其他设备扫描连接用。
    AP提供了wifi_ap_start函数，就是为这个服务的。
    1. int wifi_ap_start(const char *ssid, const char *password);
  • ssid: 路由器的名称
  • password：路由器密码

STA逻辑说明

STA就是扮演类似于手机这种角色，可以连接路由器。
STA提供了wifi_sta_connect函数，来实现连接路由器的功能。

  1. int wifi_sta_connect(const char *ssid, const char *password, const char *hostname)
  • ssid: 要连接的路由器名称
  • password：要连接的路由器密码
  • hostname: 当前设备在路由器中显示的名称

    AP模式调试

    开发流程

    来到应用开发的根目录。
    我们编写代码的根目录为device/board/itcast/genkipi/app。
  1. 根目录下新建ap文件夹，此为项目目录。
  2. 此项目目录下新建main.c文件
  3. 此项目目录下新建BUILD.gn文件
  4. 修改根目录下的BUILD.gn文件

    代码部分

    ```c

    include

    include

    include

include “cmsis_os2.h”

include “ohos_init.h”

include “wifi_ap.h”

static void startAP(void) { wifi_ap_start(“helloworld”, “12345678”); }

static void main(void) { osThreadAttr_t attr;

  1. attr.name = "ap";
  2. attr.attr_bits = 0U;
  3. attr.cb_mem = NULL;
  4. attr.cb_size = 0U;
  5. attr.stack_mem = NULL;
  6. attr.stack_size = 1024 * 2;
  7. attr.priority = 25;
  9. // Create the Thread1 task
  10. if (osThreadNew((osThreadFunc_t)startAP, NULL, &attr) == NULL) {
  11.     printf("Failed to create say hello Thread!\n");
  12. }

}

APP_FEATURE_INIT(main);

  1. ```c
  2. static_library("ap") {
  3.   sources = [ "main.c" ]
  5.   include_dirs = [
  6.     "//base/iothardware/peripheral/interfaces/inner_api",
  7.     "../../services/wifi/include",
  8.   ]
  9.   deps = [
  10.     "../../services:genkipi_services",
  11.   ]
  12. }
  1. import("//build/lite/config/component/lite_component.gni")
  3. lite_component("app") {
  4.   features = [
  5.     "ap"
  6.   ]
  7. }

校验

114.png

STA模式调试

开发流程

来到应用开发的根目录。
我们编写代码的根目录为device/board/itcast/genkipi/app。

  1. 根目录下新建sta文件夹，此为项目目录。
  2. 此项目目录下新建main.c文件
  3. 此项目目录下新建BUILD.gn文件
  4. 修改根目录下的BUILD.gn文件

    代码部分

    ```c

    include

    include

    include

include “cmsis_os2.h”

include “ohos_init.h”

include “wifi_sta.h”

static void startSta(void) { wifi_sta_connect(“xq”, “qwer1234”, “itcast”); }

static void main(void) { osThreadAttr_t attr;

  1. attr.name = "sta";
  2. attr.attr_bits = 0U;
  3. attr.cb_mem = NULL;
  4. attr.cb_size = 0U;
  5. attr.stack_mem = NULL;
  6. attr.stack_size = 1024 * 4;
  7. attr.priority = 25;
  9. // Create the Thread1 task
  10. if (osThreadNew((osThreadFunc_t)startSta, NULL, &attr) == NULL) {
  11.     printf("Failed to create say hello Thread!\n");
  12. }

}

APP_FEATURE_INIT(main);

  1. ```c
  2. static_library("sta") {
  3.   sources = [ "main.c" ]
  5.   include_dirs = [
  6.     "//base/iothardware/peripheral/interfaces/inner_api",
  7.     "../../services/wifi/include",
  8.   ]
  9.   deps = [
  10.     "../../services:genkipi_services",
  11.   ]
  12. }
  1. import("//build/lite/config/component/lite_component.gni")
  3. lite_component("app") {
  4.   features = [
  5.     "sta"
  6.   ]
  7. }

校验

114.jpg

练习题

  • 通过代码实现AP
  • 通过代码实现STA