From: Sam Moore <matches@ucc.asn.au>
Date: Fri, 16 Aug 2013 00:28:37 +0000 (+0800)
Subject: Fixed binary file access
X-Git-Url: https://git.ucc.asn.au/?a=commitdiff_plain;h=321bf62fcb0943a140dbc55bff5350e11c0eb946;p=matches%2FMCTX3420.git

Fixed binary file access

Really dumb mistakes.

If we can open the file for reading and writing, and remove the need to open/close
in both threads each time it is accessed, the efficiency might be better.

We'd still have to close the file to save changes to disk though,
might be a problem if the program crashes.
---

diff --git a/server/Makefile b/server/Makefile
index 95cd03e..009128b 100644
--- a/server/Makefile
+++ b/server/Makefile
@@ -2,7 +2,7 @@
 CXX = gcc
 FLAGS = -std=c99 -Wall -Werror -pedantic -g
 LIB = -lpthread
-OBJ = log.o sensor.o test_request.o main.o
+OBJ = log.o sensor.o query.o main.o
 RM = rm -f
 
 BIN = server
diff --git a/server/main.c b/server/main.c
index 524f550..5e2c6c8 100644
--- a/server/main.c
+++ b/server/main.c
@@ -9,7 +9,7 @@
 #include <signal.h> // for signal handling
 
 // --- Custom headers --- //
-
+#include "query.h"
 #include "log.h"
 #include "options.h"
 #include "sensor.h"
@@ -74,7 +74,7 @@ int main(int argc, char ** argv)
 	}
 
 	// run request thread in the main thread
-	Query_Request(NULL); //TODO: Replace with FastCGI code
+	Query_Main(NULL); //TODO: Replace with FastCGI code
 	return 0;
 }
 
diff --git a/server/query.c b/server/query.c
index 7a9ab16..8499e37 100644
--- a/server/query.c
+++ b/server/query.c
@@ -6,7 +6,7 @@
 
 
 
-
+#include "query.h"
 
 #include "sensor.h"
 #include "log.h"
@@ -32,8 +32,7 @@ void QuerySensor(int id) //TODO: This code will form the SensorHandler FastCGI f
 		}
 		else
 		{
-			fseek(file, 0, SEEK_SET);
-			rewind(file);
+			fseek(file, (s->read_offset)*sizeof(DataPoint), SEEK_SET);
 			amount_read = fread(&buffer, sizeof(DataPoint), QUERY_BUFSIZ, file);
 			s->read_offset += amount_read;
 			Log(LOGDEBUG, "Read %d data points; offset now at %d", amount_read, s->read_offset);
diff --git a/server/sensor.c b/server/sensor.c
index f1ec5dc..a3d3f0b 100644
--- a/server/sensor.c
+++ b/server/sensor.c
@@ -105,13 +105,12 @@ void * Sensor_Main(void * arg)
 		// CRITICAL SECTION (no threads should be able to read/write the file at the same time)
 		pthread_mutex_lock(&(s->mutex));
 
-			// Open binary file and dump buffer into it
-			FILE * file = fopen(s->filename, "wb");
+			// Open binary file in append mode and dump buffer into it
+			FILE * file = fopen(s->filename, "ab");
 			if (file == NULL)
 			{
-				Fatal("Couldn't open file \"%s\" mode wb - %s", s->filename, strerror(errno));
+				Fatal("Couldn't open file \"%s\" mode ab - %s", s->filename, strerror(errno));
 			}
-			fseek(file, 0, SEEK_END);
 			int amount_written = fwrite(s->buffer, sizeof(DataPoint), SENSOR_DATABUFSIZ, file);
 			if (amount_written != SENSOR_DATABUFSIZ)
 			{