Sector list (#7)

* added FAT sectors

Author: Beakerboy

tests/test_vbaProjectCompiler.py

@@ -18,3 +18,25 @@ def test_header():
     result = project.header()
     expected = b'\xD0\xCF\x11\xE0\xA1\xB1\x1A\xE1\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x3E\x00\x03\x00\xFE\xFF\x09\x00\x06\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x01\x00\x00\x00\x01\x00\x00\x00\x00\x00\x00\x00\x00\x10\x00\x00\x02\x00\x00\x00\x01\x00\x00\x00\xFE\xFF\xFF\xFF\x00\x00\x00\x00'
     assert result == expected
+
+def test_streamSectors():
+    project = VbaProject('.')
+    list1 = [7]
+    list2 = [4, 5, 6, 8, 16, 9, 10, 11, 12, 13, 14, 15, 17]
+    project.addStreamSectorList(list1)
+    assert project.countStreams() == 1
+    project.addStreamSectorList(list2)
+    assert project.countStreams() == 2
+    result = project.streamSectors
+    assert result == [list1, list2]
+    assert project.getFatChainLength() == 17
+    assert project.countFatChainSectors() == 1
+
+    result = project.writeFatSectorList()
+    empty = b'\xff\xff\xff\xff'
+    emptyLine = empty * 4
+    padding = emptyLine * 27
+    expected = b'\x00\x00\x00\x00' + padding
+    assert result == expected
+   
+    

vbaProjectCompiler/main.py

@@ -22,6 +22,12 @@ class VbaProject:
     #data members of class
     path = "."  #path to the project root
 
+    #Each element is a chain of sector numbers for a particular stream.
+    streamSectors = []
+
+    #A list of sectors that contain FAT chain information.
+    fatSectors = []
+
     #class default constructor
     def __init__(self, path): 
           self.path = path
@@ -96,17 +102,24 @@ def header(self):
         csectDif = LONG_ZERO
         header += csectDif
 
-        #sectFat = getFirst109FatSectors()
+        #sectFat = writeFatSectorList()
         #header += sectFat
         return header
 
+    def addStreamSectorList(self, list):
+        """Add a list of sector numbers to the FAT table."""
+        self.streamSectors.append(list)
+
+    def countStreams(self):
+        """Return the number of streams defined in the FAT table."""
+        return len(self.streamSectors)
+
     def writeFat(i):
         return 1
 
     def countFatChainSectors(self):
         """Calculate the number of sectors needed to express the FAT chain."""
-        #return self.getFatChainLength() / 512 + 1 #intdiv, roundup.
-        return 1
+        return self.getFatChainLength() // 511 + 1
 
     def getFirstDirectoryChainSector(self):
         return 1
@@ -120,22 +133,28 @@ def countMiniFatChainSectors(self):
     def getFirstMiniChainSector(self):
         return 2
 
-    def getFirst109FatSectors(self):
-        #return an array of 109 4-byte numbers 
-        #00000000 followed by FFFFFFFF 108 times
-        return "00000000";
+    def writeFatSectorList(self):
+        """Create a 436 byte stream of the first 109 FAT sectors, padded with \\xFF"""
+        list = bytearray(b'\x00\x00\x00\x00')
+        if self.countFatChainSectors() > 1:
+            #the second FAT sector is number 128.
+            pass
+        list = list.ljust(436, b'\xff')
+        return list
+
+    def getFatSectors(self):
+        sectorList = [0]
+        # add 
+        return sectorList
 
     def writeFatSector(self, i):
         """return a 512 byte sector"""
         return "FE FF FF FF"
         # followed by 511 bytes
 
     def getFatChainLength(self):
-        total = 0
-        #get the length of the fat chain including termination and beginning codes
-        #Total = getDirectoryChainLength() + 1
-        #Total += getMiniFatChainLength() + 1
-        #for stream in streams:
-        #  total += stream.getChainLength() + 1
-        #total += total % 511 #add one double for each sector
+        """Count the number of entries in the complete FAT chain."""
+        total = 1
+        for stream in self.streamSectors:
+            total += len(stream) + 1
         return total