Switch to 32-bit floats

Makefile

@@ -2,13 +2,13 @@
 # Single lora testing app
 
 CC=g++
-CFLAGS=-c -Wall `pkg-config --cflags 'libprotobuf-c >= 1.0.0'`
-LIBS=-lwiringPi -lprotobuf-c
+CFLAGS=-c -Wall `pkg-config --cflags sqlite3 'libprotobuf-c >= 1.0.0'`
+LIBS=-lwiringPi -lprotobuf-c -lsqlite3
 
 all: dragino_lora_app
 
-dragino_lora_app: main.o protobuf.o message.pb-c.o
-	$(CC) main.o protobuf.o message.pb-c.o $(LIBS) -o dragino_lora_app
+dragino_lora_app: main.o protobuf.o message.pb-c.o database.o
+	$(CC) main.o protobuf.o database.o message.pb-c.o $(LIBS) -o dragino_lora_app
 
 main.o: main.c protobuf.h
 	$(CC) $(CFLAGS) main.c
@@ -18,6 +18,9 @@ protobuf.o: message.pb-c.h protobuf.c protobuf.h
 
 protobuf.h: message.pb-c.h
 
+database.o: database.c database.h
+	$(CC) $(CFLAGS) database.c -o database.o
+
 message.pb-c.o: message.pb-c.h message.pb-c.c
 	$(CC) $(CFLAGS) message.pb-c.c -o message.pb-c.o
 

database.c

@@ -0,0 +1,53 @@
+#include "database.h"
+#include <assert.h>
+#include <stdio.h>
+#include <stddef.h>
+
+void database_state_init(struct database_state* s, const char* db_path) {
+    int return_code;
+    return_code = sqlite3_open_v2(db_path, &s->vm, SQLITE_OPEN_READWRITE, NULL);
+    assert(return_code == SQLITE_OK);
+}
+
+void database_state_free(struct database_state* s) {
+    sqlite3_close_v2(s->vm);
+}
+
+void database_write_active(struct database_state* s, int collar_id, int active_status) {
+    const char query[] = "UPDATE collar SET active=? WHERE id=?";
+    int return_code;
+
+    sqlite3_stmt* stmt;
+    return_code = sqlite3_prepare_v2(s->vm, query, sizeof(query), &stmt, NULL);
+    assert(return_code == SQLITE_OK);
+    return_code = sqlite3_bind_int(stmt, 1, active_status);
+    assert(return_code == SQLITE_OK);
+    return_code = sqlite3_bind_int(stmt, 2, collar_id);
+    assert(return_code == SQLITE_OK);
+
+    do {
+        return_code = sqlite3_step(stmt);
+    } while(return_code == SQLITE_ROW);
+    assert(return_code == SQLITE_DONE);
+}
+
+void database_write_location(struct database_state* s, int collar_id, double x, double y) {
+    const char query[] = "INSERT INTO data_point(collar_id, longitude, latitude, datetime)"
+        "VALUES (?, ?, ?, datetime('now'))";
+    int return_code;
+
+    sqlite3_stmt* stmt;
+    return_code = sqlite3_prepare_v2(s->vm, query, sizeof(query), &stmt, NULL);
+    assert(return_code == SQLITE_OK);
+    return_code = sqlite3_bind_int(stmt, 1, collar_id);
+    assert(return_code == SQLITE_OK);
+    return_code = sqlite3_bind_double(stmt, 2, x);
+    assert(return_code == SQLITE_OK);
+    return_code = sqlite3_bind_double(stmt, 3, y);
+    assert(return_code == SQLITE_OK);
+
+    do {
+        return_code = sqlite3_step(stmt);
+    } while(return_code == SQLITE_ROW);
+    assert(return_code == SQLITE_DONE);
+}

database.h

@@ -0,0 +1,14 @@
+#include <sqlite3.h>
+
+extern "C" {
+
+struct database_state {
+    sqlite3* vm;
+};
+
+void database_state_init(struct database_state* s, const char* db_path);
+void database_state_free(struct database_state* s);
+void database_write_active(struct database_state* s, int collar_id, int active_status);
+void database_write_location(struct database_state* s, int collar_id, double x, double y);
+
+}

message.proto

@@ -3,8 +3,8 @@ syntax = "proto2";
 package Fenceless;
 
 message Coordinate {
-    required double x = 1;
-    required double y = 2;
+    required float x = 1;
+    required float y = 2;
 }
 
 message CollarResponse {

sample.c

@@ -0,0 +1,9 @@
+#include "database.h"
+
+int main() {
+    struct database_state state;
+    database_state_init(&state, "data.sqlite");
+    database_write_active(&state, 1, 1);
+    database_write_location(&state, 1, 5.0, 5.0);
+    database_state_free(&state);
+}