Test mDns

Add modifications needed to the httpd freertos example Fixes raspberrypi#272
peterharperuk · Oct 3, 2022 · 42d24ce · 42d24ce
1 parent adc509b
commit 42d24ce
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Showing 4 changed files with 67 additions and 3 deletions.
diff --git a/pico_w/freertos/httpd/CMakeLists.txt b/pico_w/freertos/httpd/CMakeLists.txt
@@ -13,6 +13,7 @@ target_include_directories(picow_freertos_httpd_nosys PRIVATE
 target_link_libraries(picow_freertos_httpd_nosys
         pico_cyw43_arch_lwip_threadsafe_background
         pico_lwip_http
+        pico_lwip_mdns
         pico_stdlib
         FreeRTOS-Kernel-Heap4 # FreeRTOS kernel and dynamic heap
         )
@@ -35,6 +36,7 @@ target_include_directories(picow_freertos_httpd_sys PRIVATE
 target_link_libraries(picow_freertos_httpd_sys
         pico_cyw43_arch_lwip_sys_freertos
         pico_lwip_http
+        pico_lwip_mdns
         pico_stdlib
         FreeRTOS-Kernel-Heap4 # FreeRTOS kernel and dynamic heap
         )

diff --git a/pico_w/freertos/httpd/FreeRTOSConfig.h b/pico_w/freertos/httpd/FreeRTOSConfig.h
@@ -47,7 +47,7 @@
 #define configUSE_TICK_HOOK                     0
 #define configTICK_RATE_HZ                      ( ( TickType_t ) 1000 )
 #define configMAX_PRIORITIES                    32
-#define configMINIMAL_STACK_SIZE                ( configSTACK_DEPTH_TYPE ) 256
+#define configMINIMAL_STACK_SIZE                ( configSTACK_DEPTH_TYPE ) 1024
 #define configUSE_16_BIT_TICKS                  0
 
 #define configIDLE_SHOULD_YIELD                 1

diff --git a/pico_w/freertos/httpd/lwipopts.h b/pico_w/freertos/httpd/lwipopts.h
@@ -7,8 +7,14 @@
 // This example uses a common include to avoid repetition
 #include "lwipopts_examples_common.h"
 
+// The following is needed to test mDns
+#define LWIP_MDNS_RESPONDER 1
+#define LWIP_IGMP 1
+#define LWIP_NUM_NETIF_CLIENT_DATA 1
+#define MDNS_RESP_USENETIF_EXTCALLBACK  1
+
 #if !NO_SYS
-#define TCPIP_THREAD_STACKSIZE 1024
+#define TCPIP_THREAD_STACKSIZE 2048 // mDNS needs more stack
 #define DEFAULT_THREAD_STACKSIZE 1024
 #define DEFAULT_RAW_RECVMBOX_SIZE 8
 #define TCPIP_MBOX_SIZE 8

diff --git a/pico_w/freertos/httpd/picow_freertos_httpd.c b/pico_w/freertos/httpd/picow_freertos_httpd.c
@@ -8,6 +8,8 @@
 #include "pico/stdlib.h"
 
 #include "lwip/ip4_addr.h"
+#include "lwip/apps/mdns.h"
+#include "lwip/init.h"
 
 #include "FreeRTOS.h"
 #include "task.h"
@@ -20,12 +22,51 @@ void httpd_init(void);
 
 #define TEST_TASK_PRIORITY				( tskIDLE_PRIORITY + 1UL )
 
+#if LWIP_MDNS_RESPONDER
+static void srv_txt(struct mdns_service *service, void *txt_userdata)
+{
+  err_t res;
+  LWIP_UNUSED_ARG(txt_userdata);
+
+  res = mdns_resp_add_service_txtitem(service, "path=/", 6);
+  LWIP_ERROR("mdns add service txt failed\n", (res == ERR_OK), return);
+}
+#endif
+
+#if LWIP_MDNS_RESPONDER
+// Return some characters from the ascii representation of the mac address
+// e.g. 112233445566
+// chr_off is index of character in mac to start
+// chr_len is length of result
+// chr_off=8 and chr_len=4 would return "5566"
+// Return number of characters put into destination
+static size_t get_mac_ascii(int idx, size_t chr_off, size_t chr_len, char *dest_in) {
+    static const char hexchr[16] = "0123456789ABCDEF";
+    uint8_t mac[6];
+    char *dest = dest_in;
+    assert(chr_off + chr_len <= (2 * sizeof(mac)));
+    cyw43_hal_get_mac(idx, mac);
+    for (; chr_len && (chr_off >> 1) < sizeof(mac); ++chr_off, --chr_len) {
+        *dest++ = hexchr[mac[chr_off >> 1] >> (4 * (1 - (chr_off & 1))) & 0xf];
+    }
+    return dest - dest_in;
+}
+#endif
+
 void main_task(__unused void *params) {
     if (cyw43_arch_init()) {
         printf("failed to initialise\n");
         return;
     }
+
     cyw43_arch_enable_sta_mode();
+
+    char hostname[sizeof(CYW43_HOST_NAME) + 4];
+    memcpy(&hostname[0], CYW43_HOST_NAME, sizeof(CYW43_HOST_NAME) - 1);
+    get_mac_ascii(CYW43_HAL_MAC_WLAN0, 8, 4, &hostname[sizeof(CYW43_HOST_NAME) - 1]);
+    hostname[sizeof(hostname) - 1] = '\0';
+    netif_set_hostname(&cyw43_state.netif[CYW43_ITF_STA], hostname);
+
     printf("Connecting to WiFi...\n");
     if (cyw43_arch_wifi_connect_timeout_ms(WIFI_SSID, WIFI_PASSWORD, CYW43_AUTH_WPA2_AES_PSK, 30000)) {
         printf("failed to connect.\n");
@@ -34,14 +75,29 @@ void main_task(__unused void *params) {
         printf("Connected.\n");
     }
 
+#if LWIP_MDNS_RESPONDER
+    mdns_resp_init();
+    printf("mdns host name %s.local\n", hostname);
+#if LWIP_VERSION_MAJOR >= 2 && LWIP_VERSION_MINOR >= 2
+    mdns_resp_add_netif(&cyw43_state.netif[CYW43_ITF_STA], hostname);
+    mdns_resp_add_service(&cyw43_state.netif[CYW43_ITF_STA], "picow_freertos_httpd", "_http", DNSSD_PROTO_TCP, 80, srv_txt, NULL);
+#else
+    mdns_resp_add_netif(&cyw43_state.netif[CYW43_ITF_STA], hostname, 60);
+    mdns_resp_add_service(&cyw43_state.netif[CYW43_ITF_STA], "picow_freertos_httpd", "_http", DNSSD_PROTO_TCP, 80, 60, srv_txt, NULL);
+#endif
+#endif
+
     printf("\nReady, running httpd at %s\n", ip4addr_ntoa(netif_ip4_addr(netif_list)));
     httpd_init();
 
     while(true) {
-        // not much to do as LED is in another task, and we're using RAW (callback) lwIP API
         vTaskDelay(100);
     }
 
+#if LWIP_MDNS_RESPONDER
+    mdns_resp_remove_netif(&cyw43_state.netif[CYW43_ITF_STA]);
+#endif
+
     cyw43_arch_deinit();
 }