worked on FAT32 stuff

ext/sd/fat32/FS.h

@@ -2,6 +2,7 @@
 
 #include <cstdint>
 #include <functional>
+#include <vector>
 
 #include "Structs.h"
 
@@ -75,33 +76,24 @@ namespace FAT32 {
 			return File(*this, dea.getSize(), dea.getFirstCluster());
 		}
 
-		/** open the given file for reading*/
+		/** open the given file for reading */
 		File2 open2(const DirEntryAt& dea) {
 			return File2(*this, dea);
 		}
 
-		/** create a new file for writing, in the given directory */
-		File2 create2(const char* name) {
+		/** get or create a file with the given name */
+		File2 getOrCreateFile(const char* name) {
 
-			ClusterNr dirStartCluster = 2;	// TODO
+			DirEntryAt dea = getDirEntry(name, true);
 
-			//if (!dea.isValid())			{Log::addError(NAME, "create2(): not a valid DirEntry");}
-			//if (!dea.isDirectory())		{Log::addError(NAME, "create2(): not a directory");}
-			DirIterator di(*this, dirStartCluster);
+			// new file -> allocate the first cluster
+			if (dea.getFirstCluster() == 0) {
+				ClusterNr firstCluster = allocFreeCluster(0);
+				dea.setFirstCluster(firstCluster);
+				write(dea);
+			}
 
-			// allocate a new directory entry for the file
-			DirEntryAt dea2 = di.nextFree();
-			dea2.setName(name);
-			dea2.setSize(0);
-
-			// allocate the file's first cluster
-			ClusterNr firstCluster = allocFreeCluster(0);
-			dea2.setFirstCluster(firstCluster);
-
-			// write the file description
-			write(dea2);
-
-			return File2(*this, dea2);
+			return File2(*this, dea);
 
 		}
 
@@ -132,18 +124,36 @@ namespace FAT32 {
 
 			Log::addInfo(NAME, "Bytes/Sector: %d, Sector/Cluster: %d, FATs: %d, RootDir: %d", desc.bytesPerSector, desc.sectorsPerCluster, desc.numberOfFATs, desc.rootDirFirstCluster);
 
-			/*
-			std::cout << (int)desc.bytesPerSector << std::endl;
-			std::cout << (int)desc.sectorsPerCluster << std::endl;
-			std::cout << (int)desc.numReservedSectors << std::endl;
-			std::cout << (int)desc.numberOfFATs << std::endl;
-			std::cout << (int)desc.sectorsPerFAT << std::endl;
-			std::cout << (int)desc.rootDirFirstCluster << std::endl;
+		}
 
-			std::cout << tmp.startOfFAT << std::endl;
-			std::cout << tmp.startOfFirstDataCluster << std::endl;
-			std::cout << tmp.startOfFirstRootDirCluster << std::endl;
-			*/
+		/** get (or create, if needed) a DirEntry with the given name */
+		DirEntryAt getDirEntry(const char* name, bool createIfNeeded) {
+
+			// TODO: support for sub folders)
+
+			// start at the root folder
+			ClusterNr dirStartCluster = 2;
+
+			{	// search for a matching existing entry
+				DirIterator di(*this, dirStartCluster);
+				while(true) {
+					DirEntryAt dea = di.nextUsable();
+					if (!dea.isValid()) {break;}
+					if (dea.getName() == name) {return dea;}
+				}
+			}
+
+			// no matching entry found
+			if (!createIfNeeded) {return DirEntryAt::invalid();}
+
+			{	// allocate a new DirEntry for the file
+				DirIterator di(*this, dirStartCluster);
+				DirEntryAt dea = di.nextFree();
+				dea.setName(name);
+				dea.setSize(0);
+				dea.setFirstCluster(0);
+				return dea;
+			}
 
 		}