Class: Resedit::MZHeader

Inherits:
Changeable show all
Defined in:
lib/resedit/mz/mz_header.rb

Constant Summary collapse

MAGIC = 
0x5a4D
BLK = 
0x200
PARA = 
0x10
HSIZE = 
0x1C

Constants inherited from Changeable

Changeable::COL_CHANGED, Changeable::COL_ORIGINAL, Changeable::HOW_CHANGED, Changeable::HOW_ORIGINAL, Changeable::LOG

Instance Attribute Summary collapse

Instance Method Summary collapse

Methods inherited from Changeable

#addData, #bytes, #changed?, #colStr, #colVal, #curcol, #dbgdump, #debug, #getChanges, #getData, #hex, #insert, #loadChanges, #parseHow, #revert, #saveChanges, #saveData, #undo

Constructor Details

#initialize(mz, file, size) ⇒ MZHeader 



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# File 'lib/resedit/mz/mz_header.rb', line 13

def initialize(mz, file, size)
    raise "Not MZ file" if size < HSIZE
    @mz = mz
    super(file, HSIZE)
    @fsize = size
    @_infoOrig = loadInfo()
    @_info = nil
    @info = @_infoOrig
    raise "Not MZ file" if MAGIC != @info[:Magic]
    addData(file, headerSize() - HSIZE)
end

Instance Attribute Details

#info ⇒ Object (readonly)

Returns the value of attribute info.



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# File 'lib/resedit/mz/mz_header.rb', line 11

def info
  @info
end

#mz ⇒ Object (readonly)

Returns the value of attribute mz.



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# File 'lib/resedit/mz/mz_header.rb', line 11

def mz
  @mz
end

Instance Method Details

#addHeaderSize(size) ⇒ Object 



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# File 'lib/resedit/mz/mz_header.rb', line 78

def addHeaderSize(size)
    mode(HOW_CHANGED)
    paras = size/16 + (size%16 == 0 ? 0 : 1)
    append("00" * (paras * PARA))
    changeSize(fileSize() + paras * PARA)
    change(8, [@info[:HeaderParagraphs] + paras].pack('v'))
end

#addReloc(ofs) ⇒ Object 



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# File 'lib/resedit/mz/mz_header.rb', line 117

def addReloc(ofs)
    mode(HOW_CHANGED)
    #check relocation exists
    for i in 0..@info[:NumberOfRelocations]-1
        rel = getRelocation(i)
        if @mz.body.seg2Linear(rel[0], rel[1]) == ofs
            return false
        end
    end
    #add relocation
    if freeSpace()<4
        addHeaderSize(4)
        mode(HOW_CHANGED)
    end
    val = @mz.body.linear2seg(ofs)
    pos = @info[:RelocTableOffset]+@info[:NumberOfRelocations]*4
    cnt = @info[:NumberOfRelocations]
    change(pos, val.pack('vv'))
    change(6, [cnt+1].pack('v'))
    return true
end

#change(ofs, bytes) ⇒ Object 



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# File 'lib/resedit/mz/mz_header.rb', line 37

def change(ofs, bytes)
    super(ofs, bytes)
    @_info = nil if (ofs < HSIZE)
end

#changeSize(size) ⇒ Object 



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# File 'lib/resedit/mz/mz_header.rb', line 53

def changeSize(size)
    mode(HOW_CHANGED)
    mod = size % BLK
    ch = [mod, size / BLK + (mod ? 1 : 0)]
    change(2, ch.pack('vv'))
end

#fileSize ⇒ Object 



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# File 'lib/resedit/mz/mz_header.rb', line 92

def fileSize()
    sz = @info[:BlocksInFile] * BLK
    if @info[:BytesInLastBlock] != 0
        sz -= BLK - @info[:BytesInLastBlock]
    end
    return sz
end

#freeSpace(middle = false) ⇒ Object 



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# File 'lib/resedit/mz/mz_header.rb', line 112

def freeSpace(middle = false)
    return @info[:RelocTableOffset] - HSIZE  if middle
    return headerSize() - HSIZE - @info[:NumberOfRelocations] * 4
end

#getRelocation(idx) ⇒ Object 



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# File 'lib/resedit/mz/mz_header.rb', line 101

def getRelocation(idx)
    raise "Wrong relocation index " if idx<0 || idx>@info[:NumberOfRelocations]
    return getData(@info[:RelocTableOffset] + idx * 4, 4).unpack('vv')
end

#headerSize ⇒ Object 



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# File 'lib/resedit/mz/mz_header.rb', line 87

def headerSize()
    return @info[:HeaderParagraphs] * PARA
end

#loadInfo ⇒ Object 



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# File 'lib/resedit/mz/mz_header.rb', line 43

def loadInfo()
    v = getData(0, HSIZE).unpack('v*')
    return  {:Magic => v[0], :BytesInLastBlock => v[1], :BlocksInFile => v[2], :NumberOfRelocations => v[3],
             :HeaderParagraphs => v[4], :MinExtraParagraphs => v[5], :MaxExtraParagraphs => v[6],
             :SS => v[7], :SP => v[8], :Checksum => v[9], :IP => v[10], :CS => v[11],
             :RelocTableOffset => v[12], :OverlayNumber => v[13]
             }
end

#mode(how) ⇒ Object 



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# File 'lib/resedit/mz/mz_header.rb', line 26

def mode(how)
    super(how)
    if @mode == HOW_ORIGINAL
        @info = @_infoOrig
    else
        @_info = loadInfo() if  !@_info
        @info = @_info
    end
end

#print(what, how) ⇒ Object 



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# File 'lib/resedit/mz/mz_header.rb', line 139

def print(what, how)
    mode(parseHow(how))
    if what == "header"
        ofs=0
        @info.each{|k,v|
            printf("%20s:\t%s\n", k.to_s, colVal(ofs, 2))
            ofs+=2
        }
        puts
        fsz = fileSize()
        hsz = headerSize()
        s = colStr(sprintf("%d (%X)", fsz,fsz), changed?(2, 4))
        printf("mz file size: %s\treal file size: %d (0x%X)\n", s, @fsize, @fsize)
        printf("header size: %s\n", colStr(hsz, changed?(8, 2)))
        printf("code size: %s\n", colStr(fsz - hsz, @mz.body.changed?(0)))
        printf("reloc table size: %s\n", colStr(@info[:NumberOfRelocations] * 4, changed?(6, 2)))
        printf("free space in header: before relocs 0x%X,  after relocs 0x%X\n", freeSpace(true), freeSpace())
        return true
    end
    @mz.body.mode(@mode)
    if what == "reloc"
        ofs = @info[:RelocTableOffset]
        for i in 0..@info[:NumberOfRelocations]-1
            s1 = colVal(ofs,2)
            s2 = colVal(ofs+2,2)
            s3 = @mz.body.segData(getRelocation(i), 2, true)
            printf("%08X\t%s:%s\t= %s\n", ofs, s2, s1, s3)
            ofs += 4
        end
        return true
    end
end

#rebuildHeader(codesize) ⇒ Object 



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# File 'lib/resedit/mz/mz_header.rb', line 60

def rebuildHeader(codesize)
    mode(HOW_ORIGINAL)
    ss = @info[:SS]
    cs = @info[:CS]
    sz = fileSize()-headerSize()
    codesize += PARA - codesize % PARA if codesize % PARA!=0
    changeSize(sz + codesize + headerSize())
    paras = codesize / PARA
    change(14, [ss+paras].pack('v'))
    change(22, [cs+paras].pack('v'))
    for i in 0..@mz.header.info[:NumberOfRelocations]-1
        rel = getRelocation(i)
        rel[1]+=paras
        setRelocation(i, rel)
    end
    return codesize
end

#setRelocation(idx, data) ⇒ Object 



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# File 'lib/resedit/mz/mz_header.rb', line 106

def setRelocation(idx, data)
    raise "Wrong relocation index " if idx<0 || idx>@info[:NumberOfRelocations]
    change(@info[:RelocTableOffset] + idx * 4, data.pack('vv'))
end