Diff: resources/gas_sensor.cpp

Revision:

0:950566b0e099

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/resources/gas_sensor.cpp	Thu Oct 30 21:44:12 2014 +0000
@@ -0,0 +1,62 @@
+// gas sensor resource implementation
+
+#include "mbed.h"
+#include "nsdl_support.h"
+
+#define GAS_RES_ID    "11102/0/5700"
+#define GAS_RES_RT    "urn:X-mbed:gas-sensor"
+
+extern Serial pc;
+uint8_t gas_max_age = 0; 
+uint8_t gas_content_type = 50;
+
+AnalogIn gasSensor(A0);
+int gas_percent;
+char gasPctString[5];
+
+/* Only GET method allowed */
+static uint8_t gas_sensor_resource_cb(sn_coap_hdr_s *received_coap_ptr, sn_nsdl_addr_s *address, sn_proto_info_s * proto)
+{
+    sn_coap_hdr_s *coap_res_ptr = 0;
+    gas_percent = gasSensor.read() * 100;
+    sprintf(gasPctString,"%d", gas_percent);
+    pc.printf("gas callback\r\n");
+    pc.printf("gas percent %s\r\n", gasPctString);
+
+    if(received_coap_ptr->msg_code == COAP_MSG_CODE_REQUEST_GET)
+    {
+        coap_res_ptr = sn_coap_build_response(received_coap_ptr, COAP_MSG_CODE_RESPONSE_CONTENT);
+
+        coap_res_ptr->payload_len = strlen(gasPctString);
+        coap_res_ptr->payload_ptr = (uint8_t*)gasPctString;
+        
+        coap_res_ptr->content_type_ptr = &gas_content_type;
+        coap_res_ptr->content_type_len = sizeof(gas_content_type);
+        
+        coap_res_ptr->options_list_ptr = (sn_coap_options_list_s*)nsdl_alloc(sizeof(sn_coap_options_list_s));
+        if(!coap_res_ptr->options_list_ptr)
+            {
+            pc.printf("cant alloc option list for max-age\r\n");
+            coap_res_ptr->options_list_ptr = NULL; //FIXME report error and recover
+            }
+        memset(coap_res_ptr->options_list_ptr, 0, sizeof(sn_coap_options_list_s));
+        coap_res_ptr->options_list_ptr->max_age_ptr = &gas_max_age;
+        coap_res_ptr->options_list_ptr->max_age_len = sizeof(gas_max_age);
+
+        sn_nsdl_send_coap_message(address, coap_res_ptr);
+        nsdl_free(coap_res_ptr->options_list_ptr);
+        coap_res_ptr->options_list_ptr = NULL;
+        coap_res_ptr->content_type_ptr = NULL;// parser_release below tries to free this memory
+
+    }
+
+    sn_coap_parser_release_allocated_coap_msg_mem(coap_res_ptr);
+
+    return 0;
+}
+
+int create_gas_sensor_resource(sn_nsdl_resource_info_s *resource_ptr)
+{
+    nsdl_create_dynamic_resource(resource_ptr, sizeof(GAS_RES_ID)-1, (uint8_t*)GAS_RES_ID, sizeof(GAS_RES_RT)-1, (uint8_t*)GAS_RES_RT, 0, &gas_sensor_resource_cb, (SN_GRS_GET_ALLOWED));
+    return 0;
+}
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