From 72aac552ef0e87d71ac14e1f324b3916cea5ddba Mon Sep 17 00:00:00 2001
From: Mattias Buelens <mattias@buelens.com>
Date: Wed, 9 Sep 2015 22:56:25 +0200
Subject: [PATCH] Cooja: Track CFS file size

Previously, the Cooja mote assumed that its file was always initially empty (file.endptr == 0). Therefore, a file uploaded to a mote's CFS could never be read by the mote, as the mote would prevent reads from going past the EOF (indicated by endptr).

By tracking the file size and making it accessible to Cooja, the correct size of the uploaded file can be reported to the mote and allow it to read the uploaded file.
---
 platform/cooja/cfs/cfs-cooja.c                 | 18 +++++++++++++-----
 .../contikimote/interfaces/ContikiCFS.java     |  4 +++-
 2 files changed, 16 insertions(+), 6 deletions(-)

diff --git a/platform/cooja/cfs/cfs-cooja.c b/platform/cooja/cfs/cfs-cooja.c
index 0119ea5a0..40d1c3ceb 100644
--- a/platform/cooja/cfs/cfs-cooja.c
+++ b/platform/cooja/cfs/cfs-cooja.c
@@ -50,6 +50,7 @@ const struct simInterface cfs_interface;
 // COOJA variables
 #define CFS_BUF_SIZE 4000 /* Configure CFS size here and in ContikiCFS.java */
 char simCFSData[CFS_BUF_SIZE] = { 0 };
+int simCFSSize = 0;
 char simCFSChanged = 0;
 int simCFSRead = 0;
 int simCFSWritten = 0;
@@ -61,11 +62,15 @@ cfs_open(const char *n, int f)
   if(file.flag == FLAG_FILE_CLOSED) {
     file.flag = FLAG_FILE_OPEN;
     file.access = f;
-		if(f & CFS_APPEND) {
-			file.fileptr = file.endptr;
-		} else {
-	    file.fileptr = 0;
-		}
+    file.fileptr = 0;
+    file.endptr = simCFSSize;
+    if(f & CFS_WRITE) {
+      if(f & CFS_APPEND) {
+        file.fileptr = file.endptr;
+      } else {
+        file.endptr = 0;
+      }
+    }
     return 0;
   } else {
     return -1;
@@ -110,6 +115,9 @@ cfs_write(int f, const void *buf, unsigned int len)
 		if(file.fileptr > file.endptr) {
 			file.endptr = file.fileptr;
 		}
+		if(file.fileptr > simCFSSize) {
+			simCFSSize = file.fileptr;
+		}
     return len;
   } else {
     return -1;
diff --git a/tools/cooja/java/org/contikios/cooja/contikimote/interfaces/ContikiCFS.java b/tools/cooja/java/org/contikios/cooja/contikimote/interfaces/ContikiCFS.java
index 5a8dbb41e..f1985b6cc 100644
--- a/tools/cooja/java/org/contikios/cooja/contikimote/interfaces/ContikiCFS.java
+++ b/tools/cooja/java/org/contikios/cooja/contikimote/interfaces/ContikiCFS.java
@@ -120,6 +120,7 @@ public class ContikiCFS extends MoteInterface implements ContikiMoteInterface, P
     }
 
     moteMem.setByteArray("simCFSData", data);
+    moteMem.setIntValueOf("simCFSSize", data.length);
     return true;
   }
 
@@ -129,7 +130,8 @@ public class ContikiCFS extends MoteInterface implements ContikiMoteInterface, P
    * @return Filesystem data
    */
   public byte[] getFilesystemData() {
-    return moteMem.getByteArray("simCFSData", FILESYSTEM_SIZE);
+    int size = moteMem.getIntValueOf("simCFSSize");
+    return moteMem.getByteArray("simCFSData", size);
   }
 
   /**