logs to database now

Makefile

@@ -1,4 +1,4 @@
 GCC = gcc -l sqlite3 -Wall -Wextra 
 
 main: main.c
-	$(GCC) main.c -o main
+	$(GCC) -g main.c -o main

README.md

@@ -5,8 +5,9 @@ temperature and relative humidity values using a DHT11 sensor.
 
 `main.c` is the PC program that does the logging (printing to stdout). 
 
-I was working on getting it to write to an SQLite3 database, but didn't get 
+It just reads printed messages from the serial port `USB0`, and writes them back 
-further than initialising the databases. 
+into a SQLite3 database. It automatically creates the database and tables
+if they don't exist (making it do that was 90% of the work).
 
 `arduino.ino` is the Arduino IDE project that reads from the hardware using the 
 Adafruit sensors library. 
@@ -15,3 +16,8 @@ The arduino code is very arduino which isn't too nice since sine its such a tiny
 project pulling a lot of dependencies but I guess that's fine. Re-writing the 
 DHT11 library would probably be interesting to do.
 
+### Compiling
+
+For `main.c` run `make`
+
+For the `arduino.ino` track down the Adafruit DHT11/DHT22 library, import it and build the project in the Arduino IDE. 

arduino.ino

@@ -7,8 +7,7 @@
 #define DIO 3
 TM1637Display display(CLK, DIO);
 
-//THERMOMETER
+// THERMOMETER
-
 #include <Adafruit_Sensor.h>
 #include <DHT.h>
 #include <DHT_U.h>
@@ -36,7 +35,7 @@ void setup() {
   display.setBrightness(brightness);
   display.showNumberDec(8888);
 	
-	dht.begin();
+  dht.begin();
   //sensor_t sensor;
   //dht.temperature().getSensor(&sensor);
 
@@ -44,7 +43,8 @@ void setup() {
   int count = 0;
   while (!Serial) {
     if (count > 8000 * 5000) {
-      serial = false;// wait for serial port to connect. Needed for native USB port only
+      serial = false;
+      // wait for serial port to connect. Needed for native USB port only
       return;    
     }
   }

main.c

@@ -5,10 +5,18 @@
 #include <termios.h>
 #include <stdlib.h>
 #include <signal.h>
+#include <time.h>
 
 #include <sqlite3.h>
 #include <stdbool.h>
 
+#define WTHR_STATION_ID 0
+#define TIMESTAMP_FIELD 1
+#define DATA_VAL_FIELD 2
+#define STATION_ID_FIELD 3
+#define INSERT_HUM_TEMPL "INSERT INTO humidity(timestamp, value, station) VALUES(?, ?, ?)"
+#define INSERT_TEMP_TEMPL "INSERT INTO temperature(timestamp, value, station) VALUES(?, ?, ?)"
+
 sqlite3* get_db(void) {
    sqlite3 *db;
    char *zErrMsg = 0;
@@ -52,6 +60,7 @@ void ccleanup(sqlite3 *db) {
         sqlite3_close(db);
         printf("Closed DB.\n");
     }
+
 }
 
 static void call_cleanup(int signo) {
@@ -88,10 +97,10 @@ static int callback(void *retval, int argc, char **argv, char **azColName) {
 
 void initialise_db(sqlite3* db) {
     char *query = "SELECT name from sqlite_master WHERE name = 'temperature'";
-
     char *zErrMsg = 0;
     int rc;
     struct query_result r;
+
     rc = sqlite3_exec(db, query, save_qry, &r, &zErrMsg);
 
     if (rc != SQLITE_OK) {
@@ -113,15 +122,18 @@ void initialise_db(sqlite3* db) {
             call_cleanup(1);
         }
     }
-
     query = "SELECT name from sqlite_master WHERE name = 'humidity'";
-    rc = sqlite3_exec(db, query, save_qry, &r, &zErrMsg);
+
+    struct query_result re;
+    rc = sqlite3_exec(db, query, save_qry, &re, &zErrMsg);
+
     if (rc != SQLITE_OK) {
         fprintf(stderr, "SQL: %s\n", zErrMsg);
         sqlite3_free(zErrMsg);
         call_cleanup(1);
     }
-    if (r.argc == 0) {
+
+    if (re.argc == 0) {
         query = "CREATE TABLE humidity(" \
             "timestamp INT PRIMARY KEY NOT NULL," \
             "value INT NOT NULL," \
@@ -137,6 +149,34 @@ void initialise_db(sqlite3* db) {
     }
 }
 
+int check_error(int rc) {
+    if (rc != SQLITE_OK) {
+        fprintf(stderr, "SQL Error: %d\n", rc);
+        call_cleanup(1);
+    }
+    return 0;
+}
+
+int insert_rec(sqlite3 *db, char* sqlt, int value, int station, int timestamp) {
+    sqlite3_stmt * statement;
+    const char *tail = 0;
+    int rc = sqlite3_prepare_v2(db, sqlt, -1, &statement,  &tail); 
+    check_error(rc);
+    rc = sqlite3_bind_int(statement, DATA_VAL_FIELD, value);
+    check_error(rc);
+    rc = sqlite3_bind_int(statement, STATION_ID_FIELD, station);
+    check_error(rc);
+    rc = sqlite3_bind_int(statement, TIMESTAMP_FIELD, timestamp);
+    check_error(rc);
+    rc = sqlite3_step(statement);
+    if (rc != SQLITE_DONE) {
+        check_error(rc);
+    }
+    rc = sqlite3_finalize(statement);
+    check_error(rc);
+    return 0;
+}
+
 int main (int argc, char **arv) {
     sqlite3 *db = get_db();
     ccleanup(db);
@@ -149,14 +189,24 @@ int main (int argc, char **arv) {
     char string[200];
     int val;
 
+    int time_now = 0;
+    int last_time = 0;
     while(1) {
+        last_time = time_now;
+        time_now = time(NULL);
         memset(string, 0, sizeof(char) * 200);
         fscanf(serial, "%s%d", string, &val);
         if (!strcmp(string, "temp:")) {
             printf("Temperature: %d\n", val);
         }
+        if (last_time != time_now) {
+            insert_rec(db, INSERT_TEMP_TEMPL, val, WTHR_STATION_ID, time_now);
+        }
         if (!strcmp(string, "humi:")) {
             printf("Relative Humidity: %d\n", val);
+            if (last_time != time_now) {
+                insert_rec(db, INSERT_HUM_TEMPL, val, WTHR_STATION_ID, time_now);
+            }
         }
     }