//test if <file> is an ELF file by reading its magic numbers.
static void isElfFile(ELF file)
{
if (!(file.EI_MAG0 == 127 && file.EI_MAG1 == 69 && file.EI_MAG2 == 76 && file.EI_MAG3 == 70))
{
MessageBox.Show("The file you chose is not in ELF format. The program will now quit.");
Environment.Exit(0);
}
}
//opens an ELF file, <filename>, and then begins reading it. Will load program segments into <ram>, a simulated memory array.
//<test> will silence output to the log if running unit tests. <log> controls logging features.
public static void Read(string filename, Memory ram, bool test, bool log, Memory reg)
{
string elfFilename = filename;
using (FileStream strm = new FileStream(elfFilename, FileMode.Open))
{
ELF elfHeader = new ELF();
byte[] data = new byte[Marshal.SizeOf(elfHeader)];
//ram.log.Text += "\r\nOpening " + elfFilename + "...";
// Read ELF header data
strm.Read(data, 0, data.Length);
// Convert to struct
elfHeader = ByteArrayToStructure <ELF>(data);
Log("Loader.Read: Entry point: " + elfHeader.e_entry.ToString("X4"), test, log);
reg.setRegister(15, 0x0000);
Log("Loader.Read: Number of segments: " + elfHeader.e_phnum, test, log);
// Read first program header entry
int index = 1;
strm.Seek(elfHeader.e_phoff, SeekOrigin.Begin);
data = new byte[elfHeader.e_phentsize];
strm.Read(data, 0, (int)elfHeader.e_phentsize);
//read additional program header entries
ProgHeaderEnt phead = ByteArrayToStructure <ProgHeaderEnt>(data);
uint size = elfHeader.e_phoff + elfHeader.e_phentsize;
uint size2 = phead.p_offset + phead.p_filesz;
try
{
byte[] segment = new byte[phead.p_filesz];
strm.Seek(phead.p_offset, SeekOrigin.Begin);
strm.Read(segment, 0, (int)phead.p_filesz);
uint addr = phead.p_vaddr;
uint end;
ram.begin = addr;
ram.begin2 = (uint)elfHeader.e_entry;
end = writeBytes(ram, segment, addr);
Log("Loader.Read: Segment 1 - Address = " + phead.p_vaddr + ", Offset = " + phead.p_offset + ", Size = " + phead.p_filesz, test, log);
while (index < elfHeader.e_phnum)
{
strm.Seek(size, SeekOrigin.Begin);
data = new byte[elfHeader.e_phentsize];
strm.Read(data, 0, (int)elfHeader.e_phentsize);
phead = ByteArrayToStructure <ProgHeaderEnt>(data);
size = size + elfHeader.e_phentsize;
size2 = phead.p_offset + phead.p_filesz;
segment = new byte[phead.p_filesz];
strm.Seek(phead.p_offset, SeekOrigin.Begin);
strm.Read(segment, 0, (int)phead.p_filesz);
addr = phead.p_vaddr;
end = writeBytes(ram, segment, addr);
Log("Loader.Read: Segment " + (index + 1) + " - Address = " + phead.p_vaddr + ", Offset = " + phead.p_offset + ", Size = " + phead.p_filesz, test, log);
index++;
}
;
ram.end = end;
// ram.log.Text += "\r\nCalculating checksum...";
int y = ram.Checksum();
if (ram.ReadWord(0) == 0)
{
reg.cpsr = Memory.SetBitinInt(reg.cpsr, 0, true);
reg.cpsr = Memory.SetBitinInt(reg.cpsr, 1, true);
reg.cpsr = Memory.SetBitinInt(reg.cpsr, 2, true);
reg.cpsr = Memory.SetBitinInt(reg.cpsr, 3, true);
reg.cpsr = Memory.SetBitinInt(reg.cpsr, 4, true);
reg.setRegister(15, elfHeader.e_entry);
reg.setRegister(13, 0x7000);
reg.modetrack = 0;
}
else
{
reg.cpsr = Memory.SetBitinInt(reg.cpsr, 0, true);
reg.cpsr = Memory.SetBitinInt(reg.cpsr, 1, true);
reg.cpsr = Memory.SetBitinInt(reg.cpsr, 2, false);
reg.cpsr = Memory.SetBitinInt(reg.cpsr, 3, false);
reg.cpsr = Memory.SetBitinInt(reg.cpsr, 4, true);
reg.modetrack = 1;
}
// ram.log.Text += "\r\nChecksum value: " + y;
}
catch (IndexOutOfRangeException e)
{
Trace.WriteLine("RAM Overflowed. Not enough RAM was specified. Quitting.");
MessageBox.Show("RAM Overflowed. Not enough RAM was specified. Quitting.");
Environment.Exit(0);
}
}
}
