private void WriteProgramHeaders(EndianAwareBinaryWriter writer)
{
writer.Position = elfheader.ProgramHeaderOffset;
foreach (var section in Sections)
{
if (section.Size == 0 && section.SectionKind != SectionKind.BSS)
continue;
var pheader = new ProgramHeader
{
Alignment = section.SectionAlignment,
FileSize = section.AlignedSize,
MemorySize = section.AlignedSize,
Offset = section.FileOffset,
VirtualAddress = (uint)section.VirtualAddress,
PhysicalAddress = (uint)section.VirtualAddress,
Type = ProgramHeaderType.Load,
Flags =
(section.SectionKind == SectionKind.Text) ? ProgramHeaderFlags.Read | ProgramHeaderFlags.Execute :
(section.SectionKind == SectionKind.ROData) ? ProgramHeaderFlags.Read : ProgramHeaderFlags.Read | ProgramHeaderFlags.Write
};
pheader.Write(writer);
}
}
/// <summary>
/// Creates the elf32 file.
/// </summary>
/// <param name="compiler">The compiler.</param>
private void CreateElf32File()
{
using (FileStream fs = new FileStream(OutputFile, FileMode.Create, FileAccess.Write, FileShare.None))
{
Header header = new Header();
header.Type = FileType.Executable;
header.Machine = Machine;
header.SectionHeaderNumber = (ushort)(Sections.Count + 2);
header.SectionHeaderOffset = header.ElfHeaderSize;
header.CreateIdent(IdentClass.Class32, IsLittleEndian ? IdentData.Data2LSB : IdentData.Data2MSB, null);
// Calculate the concatenated size of all section's data
uint offset = 0;
foreach (Section section in Sections)
{
offset += (uint)section.Length;
}
offset += (uint)nullSection.Length;
offset += (uint)stringTableSection.Length;
// Calculate offsets
header.ProgramHeaderOffset = header.ElfHeaderSize + header.SectionHeaderEntrySize * (uint)header.SectionHeaderNumber + offset;
header.ProgramHeaderNumber = 1;
header.SectionHeaderStringIndex = 1;
EndianAwareBinaryWriter writer = new EndianAwareBinaryWriter(fs, IsLittleEndian);
// Write the ELF Header
header.Write(writer);
// Overjump the Section Header Table and write the section's data first
long tmp = fs.Position;
writer.Seek((int)(tmp + header.SectionHeaderNumber * header.SectionHeaderEntrySize), SeekOrigin.Begin);
nullSection.Write(writer);
stringTableSection.Write(writer);
// Write the _sections
foreach (Section section in Sections)
section.Write(writer);
// Jump back to the Section Header Table
writer.Seek((int)tmp, SeekOrigin.Begin);
nullSection.WriteHeader(writer);
stringTableSection.WriteHeader(writer);
// Write the section headers
foreach (Section section in Sections)
section.WriteHeader(writer);
ProgramHeader pheader = new ProgramHeader
{
Alignment = 0,
FileSize = (uint)GetSection(SectionKind.Text).Length
};
pheader.MemorySize = pheader.FileSize;
pheader.VirtualAddress = 0xFF0000;
pheader.Flags = ProgramHeaderFlags.Execute | ProgramHeaderFlags.Read | ProgramHeaderFlags.Write;
pheader.Offset = ((Section)GetSection(SectionKind.Text)).Header.Offset;
pheader.Type = ProgramHeaderType.Load;
writer.Seek((int)header.ProgramHeaderOffset, SeekOrigin.Begin);
pheader.Write(writer);
}
}
/// <summary>
/// Creates the final linked file.
/// </summary>
protected override void CreateFile()
{
using (FileStream fs = new FileStream(OutputFile, FileMode.Create, FileAccess.Write, FileShare.None))
{
Header header = new Header();
header.Type = FileType.Executable;
header.Machine = (MachineType)MachineID;
header.SectionHeaderNumber = (ushort)(Sections.Length + 2);
header.SectionHeaderOffset = header.ElfHeaderSize;
header.EntryAddress = (uint)EntryPoint.VirtualAddress;
header.CreateIdent(IdentClass.Class32, Endianness == Endianness.Little ? IdentData.Data2LSB : IdentData.Data2MSB, null);
// Calculate the concatenated size of all section's data
uint offset = 0;
ushort programHeaderNumber = 0;
foreach (Elf32LinkerSection section in Sections)
{
offset += (uint)section.Length;
if (section.SectionKind != SectionKind.BSS && section.Length > 0)
programHeaderNumber++;
}
offset += (uint)nullSection.Length;
offset += (uint)stringTableSection.Length;
// Calculate offsets
header.ProgramHeaderOffset = header.ElfHeaderSize + header.SectionHeaderEntrySize * (uint)header.SectionHeaderNumber + offset;
header.ProgramHeaderNumber = programHeaderNumber;
header.SectionHeaderStringIndex = 1;
EndianAwareBinaryWriter writer = new EndianAwareBinaryWriter(fs, Endianness);
// Write the ELF Header
header.Write(writer);
// Overjump the Section Header Table and write the section's data first
long tmp = fs.Position;
writer.Seek((int)(tmp + header.SectionHeaderNumber * header.SectionHeaderEntrySize), SeekOrigin.Begin);
nullSection.Write(writer);
stringTableSection.Write(writer);
// Write the _sections
foreach (Elf32LinkerSection section in Sections)
section.Write(writer);
// Jump back to the Section Header Table
writer.Seek((int)tmp, SeekOrigin.Begin);
nullSection.WriteHeader(writer);
stringTableSection.WriteHeader(writer);
// Write the section headers
foreach (Elf32LinkerSection section in Sections)
section.WriteHeader(writer);
writer.Seek((int)header.ProgramHeaderOffset, SeekOrigin.Begin);
foreach (Elf32LinkerSection section in Sections)
{
if (section.SectionKind == SectionKind.BSS || section.Length == 0)
continue;
ProgramHeader pheader = new ProgramHeader
{
Alignment = 0,
FileSize = (uint)section.Length,
MemorySize = (uint)section.Length,
Offset = section.Header.Offset,
VirtualAddress = (uint)section.VirtualAddress,
PhysicalAddress = (uint)section.VirtualAddress,
Type = ProgramHeaderType.Load,
Flags =
(section.SectionKind == SectionKind.Text) ? ProgramHeaderFlags.Read | ProgramHeaderFlags.Execute :
(section.SectionKind == SectionKind.ROData) ? ProgramHeaderFlags.Read :
ProgramHeaderFlags.Read | ProgramHeaderFlags.Write
};
pheader.Write(writer);
}
}
}