kolibrios/programs/develop/objconv/omf2cof.cpp

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/**************************** omf2cof.cpp *********************************
* Author: Agner Fog
* Date created: 2007-02-08
* Last modified: 2018-08-15
* Project: objconv
* Module: omf2cof.cpp
* Description:
* Module for converting OMF file to PE/COFF file
*
* Copyright 2007-2018 GNU General Public License http://www.gnu.org/licenses
*****************************************************************************/
#include "stdafx.h"
// Alignment value translation table
static const uint32 OMFAlignTranslate[8] = {0,1,2,16,256,4,0,0};
COMF2COF::COMF2COF() {
// Constructor
memset(this, 0, sizeof(*this)); // Reset everything
}
void COMF2COF::Convert() {
// Do the conversion
// Allocate variable size buffers
//NewSectIndex.SetNum(this->NSections);// Allocate section translation table
//NewSectIndex.SetZero(); // Initialize
// Call the subfunctions
ToFile.SetFileType(FILETYPE_COFF); // Set type of to file
MakeFileHeader(); // Make file header
MakeSymbolTable1(); // Make symbol table and string table entries for file and segments
MakeSymbolTable2(); // Make symbol table and string table entries for external symbols
MakeSymbolTable3(); // Make symbol table and string table entries for public symbols
MakeSymbolTable4(); // Make symbol table and string table entries for communal symbols
MakeSymbolTable5(); // Make symbol table and string table entries for local symbols
MakeSections(); // Make sections and relocation tables
CheckUnsupportedRecords(); // Make warnings if file containes unsupported record types
MakeBinaryFile(); // Put sections together
*this << ToFile; // Take over new file buffer
}
void COMF2COF::MakeFileHeader() {
// Convert subfunction: File header
// Make PE file header
NewFileHeader.Machine = PE_MACHINE_I386;
NewFileHeader.TimeDateStamp = (uint32)time(0);
NewFileHeader.SizeOfOptionalHeader = 0;
NewFileHeader.Flags = 0;
// Values inserted later:
NewFileHeader.NumberOfSections = 0;
NewFileHeader.PSymbolTable = 0;
NewFileHeader.NumberOfSymbols = 0;
}
void COMF2COF::MakeSymbolTable1() {
// Make symbol table string table and section table entries for file and segments
SCOFF_SymTableEntry sym; // Symbol table entry
SCOFF_SectionHeader sec; // Section header entry
char * ClassName; // Old segment class name
// Initialize new string table. make space for 4-bytes size
NewStringTable.Push(0, 4);
// Allocate SegmentTranslation buffer
SegmentTranslation.SetNum(SegmentNameOffset.GetNumEntries());
// Make symbol table entry for file name
memset(&sym, 0, SIZE_SCOFF_SymTableEntry);
strcpy(sym.s.Name, ".file");
sym.s.SectionNumber = COFF_SECTION_DEBUG;
sym.s.StorageClass = COFF_CLASS_FILE;
char * ShortFileName = CLibrary::ShortenMemberName(OutputFileName);
sym.s.NumAuxSymbols = 1; // File name is truncated so it will fit into the 18 bytes of SIZE_SCOFF_SymTableEntry
NewSymbolTable.Push(sym); // Store symbol table entry
// Needs auxiliary entry:
memset(&sym, 0, SIZE_SCOFF_SymTableEntry);
if (strlen(ShortFileName) < SIZE_SCOFF_SymTableEntry) {
strcpy(sym.s.Name, ShortFileName);
}
NewSymbolTable.Push(sym); // Store auxiliary symbol table entry
// Define structure of attributes
OMF_SAttrib Attributes;
// Other segment properties
uint32 SegLength, NameIndex, ClassIndex;
//uint32 Offset;
const char * sname; // Segment/section name
uint32 SegNum = 0; // Segment/section number
uint32 StringI; // New sting table index
uint32 i; // Record number
int32 j, n; // Temporary
// Loop through segments of old file
for (i = 0; i < NumRecords; i++) {
if (Records[i].Type2 == OMF_SEGDEF) {
// SEGDEF record
Records[i].Index = 3;
// Loop through entries in record. There should be only 1
while (Records[i].Index < Records[i].End) {
Attributes.b = Records[i].GetByte(); // Read attributes
if (Attributes.u.A == 0) {
// Frame and Offset only included if A = 0
Records[i].GetWord(); // Frame ignored
Records[i].GetByte();
}
//else Offset = 0;
SegLength = Records[i].GetNumeric();
NameIndex = Records[i].GetIndex();
ClassIndex = Records[i].GetIndex(); // Class index
Records[i].GetIndex(); // Overlay index ignored
sname = GetLocalName(NameIndex); // Segment name = new section name
if (Attributes.u.B) {
// Segment is big
if (Attributes.u.P) {
// 32 bit segment. Big means 2^32 bytes!
err.submit(2306);
}
else {
// 16 bit segment. Big means 2^16 bytes
SegLength = 0x10000;
}
}
// make symbol table entry
memset(&sym, 0, SIZE_SCOFF_SymTableEntry);
// Put name into string table
StringI = NewStringTable.PushString(sname);
// Put name into symbol table
//COFF_PutNameInSymbolTable(sym, sname, NewStringTable);
((uint32*)(sym.s.Name))[1] = StringI;
sym.s.SectionNumber = ++SegNum; // Count section number
sym.s.StorageClass = COFF_CLASS_STATIC;
sym.s.NumAuxSymbols = 1; // Needs 1 aux record
// Remember NewSymbolTable index
SegmentTranslation[SegNum] = NewSymbolTable.GetNumEntries();
NewSymbolTable.Push(sym); // Store symbol table entry
// Make auxiliary entry
memset(&sym, 0, SIZE_SCOFF_SymTableEntry);
// Insert section size
sym.section.Length = SegLength;
// Remember to insert NumberOfRelocations here later
// Store auxiliary symbol table entry
NewSymbolTable.Push(sym);
// Make section header
memset(&sec, 0, sizeof(sec)); // Reset section header
// Put name into section header
sprintf(sec.Name, "/%i", StringI);
// Put size into section header
sec.SizeOfRawData = SegLength;
// Alignment
switch (Attributes.u.A) {
case 0: // Absolute segment
err.submit(2307); break;
case 1: // Byte
sec.Flags |= PE_SCN_ALIGN_1; break;
case 2: // Word
sec.Flags |= PE_SCN_ALIGN_2; break;
case 3: // Paragraph
sec.Flags |= PE_SCN_ALIGN_16; break;
case 4: // Page. May be 256 or 4096, depending on system
// If we use 4096 where the source intended 256, we may get
// size and symbol offsets wrong!
sec.Flags |= PE_SCN_ALIGN_256; break;
case 5: // Dword
sec.Flags |= PE_SCN_ALIGN_4; break;
default: // Unknown alignment
err.submit(2308, Attributes.u.A);
sec.Flags |= PE_SCN_ALIGN_16; break;
}
// Get further attributes from class name
ClassName = GetLocalName(ClassIndex);
// Convert class name to upper case
n = (int32)strlen(ClassName);
for (j = 0; j < n; j++) ClassName[j] &= ~0x20;
// Search for known class names.
// Standard names are CODE, DATA, BSS, CONST, STACK
if (strstr(ClassName, "CODE") || strstr(ClassName, "TEXT")) {
// Code segment
sec.Flags |= PE_SCN_CNT_CODE | PE_SCN_MEM_EXECUTE | PE_SCN_MEM_READ;
}
else if (strstr(ClassName, "DATA")) {
// Data segment
sec.Flags |= PE_SCN_CNT_INIT_DATA | PE_SCN_MEM_READ | PE_SCN_MEM_WRITE;
}
else if (strstr(ClassName, "BSS")) {
// Unitialized data segment
sec.Flags |= PE_SCN_CNT_UNINIT_DATA | PE_SCN_MEM_READ | PE_SCN_MEM_WRITE;
}
else if (strstr(ClassName, "CONST")) {
// Constant data segment
sec.Flags |= PE_SCN_CNT_INIT_DATA | PE_SCN_MEM_READ;
}
else if (strstr(ClassName, "STACK")) {
// Stack segment. Ignore
sec.Flags |= PE_SCN_LNK_REMOVE;
err.submit(1206); // Warning: ignored
}
else {
// Unknown/user defined class. Assume data segment
sec.Flags |= PE_SCN_CNT_INIT_DATA | PE_SCN_MEM_READ | PE_SCN_MEM_WRITE;
}
// Insert pointers to relocations and raw data later
// Store section header
NewSectionHeaders.Push(sec);
}
if (Records[i].Index != Records[i].End) err.submit(1203); // Check for consistency
}
if (Records[i].Type2 == OMF_COMDAT || Records[i].Type2 == OMF_COMDEF) {
// Communal sections
err.submit(1055);
}
}
}
void COMF2COF::MakeSymbolTable2() {
// Make symbol table and string table entries for external symbols
uint32 i;
SCOFF_SymTableEntry sym; // new symbol table entry
uint32 NumExtSym = SymbolNameOffset.GetNumEntries(); // Number of external symbols
ExtdefTranslation.SetNum(NumExtSym+1); // Allocate space in translation table
// Loop through external symbol names
for (i = 1; i < NumExtSym; i++) {
// Reset symbol table entry
memset(&sym, 0, SIZE_SCOFF_SymTableEntry);
// Insert name
COFF_PutNameInSymbolTable(sym, GetSymbolName(i), NewStringTable);
// Insert storage class
sym.s.StorageClass = COFF_CLASS_EXTERNAL;
// Store symbol table entry
NewSymbolTable.Push(sym);
// Update table for translating old EXTDEF number (1-based) to new symbol table index (0-based)
ExtdefTranslation[i] = NewSymbolTable.GetNumEntries() - 1;
}
}
void COMF2COF::MakeSymbolTable3() {
// Make symbol table and string table entries for public symbols
SCOFF_SymTableEntry sym; // new symbol table entry
uint32 i; // Record index
char * string; // Symbol name
uint32 Segment; // Segment
uint32 Offset; // Offset
uint32 Namei; // Index into symbol table
SOMFLocalSymbol localsym; // Entry into LocalSymbols
// Search for PUBDEF records
for (i = 0; i < NumRecords; i++) {
if (Records[i].Type2 == OMF_PUBDEF) {
// PUBDEF record
Records[i].Index = 3;
Records[i].GetIndex(); // Group. Ignore
Segment = Records[i].GetIndex(); // Segment
if (Segment == 0) Records[i].GetWord(); // Base frame. Ignore
// Loop through strings in record
while (Records[i].Index < Records[i].End) {
string = Records[i].GetString(); // Symbol name
Offset = Records[i].GetNumeric(); // Offset to segment
Records[i].GetIndex(); // Type index. Ignore
// Reset symbol table entry
memset(&sym, 0, SIZE_SCOFF_SymTableEntry);
// Insert name
Namei = COFF_PutNameInSymbolTable(sym, string, NewStringTable);
// Insert storage class
sym.s.StorageClass = COFF_CLASS_EXTERNAL;
// Store offset
sym.s.Value = Offset;
// Section number = segment number
if (Segment == 0) sym.s.SectionNumber = COFF_SECTION_ABSOLUTE;
else sym.s.SectionNumber = (int16)Segment;
// Store symbol table entry
NewSymbolTable.Push(sym);
// Make entry into LocalSymbols to indicate that this symbol has a name
if (Segment > 0) {
// Make index into NewStringTable if we don't allready have one
if (Namei == 0) Namei = NewStringTable.PushString(string);
localsym.Offset = Offset;
localsym.Segment = Segment;
localsym.Name = Namei;
localsym.NewSymtabIndex = NewSymbolTable.GetNumEntries() - 1; // 0-based index into new symbol table
LocalSymbols.PushUnique(localsym);
}
}
if (Records[i].Index != Records[i].End) err.submit(1203); // Check for consistency
}
}
}
void COMF2COF::MakeSymbolTable4() {
// Make symbol table and string table entries for communal symbols
// Warning: Currently not supported!
}
void COMF2COF::MakeSymbolTable5() {
// Make symbol table and string table entries for local symbols.
// There is no table for local symbols in OMF files. We have to search
// through all FIXUPP records for relocation targets and assign arbitrary
// names to them.
uint32 i; // Loop counter
uint32 Target, TargetDisplacement; // Contents of FIXUPP record
uint8 byte1, byte2; // First two bytes of FIXUPP subrecord
// Bitfields in subrecords
OMF_SLocat Locat; // Structure of first two bytes of FIXUP subrecord swapped = Locat field
OMF_SFixData FixData; // Structure of FixData field in FIXUP subrecord of FIXUPP record
OMF_STrdDat TrdDat; // Structure of Thread Data field in THREAD subrecord of FIXUPP record
int8 * LastDataRecordPointer = 0; // Pointer to data in the data record that relocations refer to
uint32 LastDataRecordSize = 0; // Size of the data record that relocations refer to
SOMFLocalSymbol localsym; // Entry into LocalSymbols
uint32 LocalSymNum = 0; // Number of unnamed local symbols
char NewName[32]; // Buffer for making new name
SCOFF_SymTableEntry sym; // New symbol table entry
// Search for FIXUPP records and data records
for (i = 0; i < NumRecords; i++) {
if (Records[i].Type2 == OMF_LEDATA) {
// LEDATA record. Remember pointer to binary data in order to read inline offset
Records[i].Index = 3; // Initialize record reading
Records[i].GetIndex(); // Read segment and offset
Records[i].GetNumeric();
LastDataRecordSize = Records[i].End - Records[i].Index; // Calculate size of data
LastDataRecordPointer = Records[i].buffer + Records[i].FileOffset + Records[i].Index;
}
if (Records[i].Type2 == OMF_FIXUPP) {
// FIXUPP record
Records[i].Index = 3; // Initialize record reading
// Loop through entries in record
while (Records[i].Index < Records[i].End) {
// Read first byte
byte1 = Records[i].GetByte();
if (byte1 & 0x80) {
// This is a FIXUP subrecord
Target = 0; TargetDisplacement = 0;
// read second byte
byte2 = Records[i].GetByte();
// swap bytes and put into byte12 bitfield
Locat.bytes[1] = byte1;
Locat.bytes[0] = byte2;
// Read FixData
FixData.b = Records[i].GetByte();
// Read conditional fields
if (FixData.s.F == 0) {
if (FixData.s.Frame < 4) {
Records[i].GetIndex(); // Frame. Ignore
}
}
if (FixData.s.T == 0) {
// Target specified
Target = Records[i].GetIndex();
//uint32 TargetMethod = FixData.s.Target + FixData.s.P * 4;
}
if (FixData.s.P == 0) {
TargetDisplacement = Records[i].GetNumeric();
}
// Get inline addend
if (LastDataRecordPointer && Locat.s.Offset < LastDataRecordSize) {
int8 * inlinep = LastDataRecordPointer + Locat.s.Offset;
if (Locat.s.Location == 9 || Locat.s.Location == 13) {
TargetDisplacement += *(int32*)inlinep;
}
}
if (FixData.s.T == 0 && (FixData.s.Target == 0 || FixData.s.Target == 1)) {
// Target is local symbol
// Make entry in LocalSymbols
localsym.Offset = TargetDisplacement; // Offset to segment
localsym.Segment = Target; // Target segment
localsym.Name = 0; // Has no name yet
localsym.NewSymtabIndex = 0; // Not in new symbol table yet
// Make entry in LocalSymbols.
// PushUnique will not make an entry if this target address already
// has an entry in LocalSymbols and possibly a public name
LocalSymbols.PushUnique(localsym);
}
}
else {
// This is a THREAD subrecord. Read and ignore
TrdDat.b = byte1; // Put byte into bitfield
if (TrdDat.s.Method < 4) {
Records[i].GetIndex(); // has index field if method < 4 ?
}
}
} // Finished loop through subrecords
if (Records[i].Index != Records[i].End) err.submit(1203); // Check for consistency
}
} // Finished loop through records
// Now check LocalSymbols for unnamed symbols
for (i = 0; i < LocalSymbols.GetNumEntries(); i++) {
if (LocalSymbols[i].Name == 0) {
// Unnamed symbol. Give it a name
sprintf(NewName, "?NoName%02i", ++LocalSymNum);
// Make index in new symbol table
// Reset symbol table entry
memset(&sym, 0, SIZE_SCOFF_SymTableEntry);
// Insert name
LocalSymbols[i].Name = COFF_PutNameInSymbolTable(sym, NewName, NewStringTable);
// if (LocalSymbols[i].Name == 0) LocalSymbols[i].Name = NewStringTable.PushString(NewName);
// Store offset
sym.s.Value = LocalSymbols[i].Offset;
// Section number = segment number
sym.s.SectionNumber = LocalSymbols[i].Segment;
// Storage class
sym.s.StorageClass = COFF_CLASS_STATIC;
// Store symbol table entry
NewSymbolTable.Push(sym);
// Store index into new symbol table (0 - based)
LocalSymbols[i].NewSymtabIndex = NewSymbolTable.GetNumEntries() - 1;
}
}
}
void COMF2COF::MakeSections() {
// Make sections and relocation tables
uint32 SegNum; // Index into NewSectionHeaders = segment - 1
uint32 DesiredSegment; // Old segment number = new section number
uint32 RecNum; // Old record number
CMemoryBuffer TempBuf; // Temporary buffer for building raw data
CMemoryBuffer RelocationTable; // Temporary buffer for building new relocation table
SCOFF_Relocation rel; // New relocation table record
uint32 LastDataRecord = 0; // Index to the data record that relocations refer to
uint32 LastDataRecordSize = 0; // Size of the data record that relocations refer to
int8 * LastDataRecordPointer = 0; // Pointer to data in the data record that relocations refer to
uint32 Segment = 0; // Segment of last LEDATA, LIDATA or COMDEF record
uint32 Offset; // Offset of LEDATA or LIDATA record to segment
uint32 Size; // Size of data in LEDATA or LIDATA record
uint32 SegmentSize; // Total size of segment
uint32 LastOffset; // Offset after last LEDATA into segment
uint32 FileOffsetData; // File offset of first raw data and relocations in new file
uint32 FileOffset; // File offset of current raw data or relocations
// File offset of first data = size of file header and section headers
FileOffsetData = sizeof(SCOFF_FileHeader) + NewSectionHeaders.GetNumEntries() * sizeof(SCOFF_SectionHeader);
// Loop through segments
for (SegNum = 0; SegNum < NewSectionHeaders.GetNumEntries(); SegNum++) {
DesiredSegment = SegNum + 1; // Search for records referring to this segment
SegmentSize = NewSectionHeaders[SegNum].SizeOfRawData;
if (SegmentSize == 0) continue; // Empty segment
// Allocate temporary data buffer and reset it
TempBuf.SetSize(SegmentSize + 16);
int FillByte = 0; // Byte to fill memory with
if (NewSectionHeaders[SegNum].Flags & PE_SCN_CNT_CODE) {
// Code segment. Fill any unused bytes with NOP opcode = 0x90
FillByte = 0x90;
}
memset(TempBuf.Buf(), FillByte, SegmentSize + 16);// Reset to all 0 or NOP
// Reset relocation table buffer
RelocationTable.SetSize(0);
LastOffset = 0; LastDataRecordSize = 0;
// Search for LEDATA, LIDATA and FIXUPP records for this segment
for (RecNum = 0; RecNum < NumRecords; RecNum++) {
if (Records[RecNum].Type2 == OMF_LEDATA) {
// LEDATA record
Records[RecNum].Index = 3; // Initialize record reading
Segment = Records[RecNum].GetIndex();// Read segment number
if (Segment != DesiredSegment) continue; // Does not refer to this segment
Offset = Records[RecNum].GetNumeric();// Read offset
Size = Records[RecNum].End - Records[RecNum].Index; // Calculate size of data
LastDataRecord = RecNum; // Save for later FIXUPP that refers to this record
// Check if data within segment
if (Offset + Size > SegmentSize) {
err.submit(2309, GetSegmentName(Segment));
return;
}
if (Offset < LastOffset + LastDataRecordSize && LastOffset < Offset + Size) {
// Overlapping data records
if (Offset + 8 < LastOffset + LastDataRecordSize || !(NewSectionHeaders[SegNum].Flags & PE_SCN_CNT_CODE)) {
// Overlapping data by more than 7 bytes or not executable code
err.submit(1207);
}
else {
// Possibly backpatched code
err.submit(1208); // Warning
err.ClearError(1208); // Report only once
}
}
LastDataRecordSize = Size;
LastDataRecordPointer = Records[RecNum].buffer + Records[RecNum].FileOffset + Records[RecNum].Index;
LastOffset = Offset; // Save offset for subsequent FIXUPP records
/*// Check if data within segment
if (Offset + Size > SegmentSize) {
err.submit(2309, GetSegmentName(Segment));
continue;
} */
// Put raw data into temporary buffer
memcpy(TempBuf.Buf() + Offset, LastDataRecordPointer, Size);
} // Finished with LEDATA record
if (Records[RecNum].Type2 == OMF_LIDATA) {
// LIDATA record
Records[RecNum].Index = 3; // Initialize record reading
Segment = Records[RecNum].GetIndex();
if (Segment != DesiredSegment) continue; // Does not refer to this segment
LastDataRecord = RecNum; // Save for later FIXUPP that refers to this record
Offset = Records[RecNum].GetNumeric();// Read offset
if (Offset > SegmentSize) {
err.submit(2310); return; // Error: outside bounds
}
// Unpack LIDATA blocks recursively
Size = Records[RecNum].UnpackLIDATABlock(TempBuf.Buf() + Offset, SegmentSize - Offset);
if (Offset < LastOffset + LastDataRecordSize && LastOffset < Offset + Size) {
// Overlapping data records
err.submit(1207); // Warning
}
LastDataRecordSize = Size; // Save data size
LastOffset = Offset; // Save offset for subsequent FIXUPP records
} // Finished with LIDATA record
if (Records[RecNum].Type2 == OMF_COMDAT) {
// COMDAT record. Currently not supported by objconv
LastDataRecord = RecNum; // Save for later FIXUPP that refers to this record
Segment = 0; // Ignore any relocation referring to this
}
if (Records[RecNum].Type2 == OMF_FIXUPP) {
// FIXUPP record
if (Segment != DesiredSegment) continue; // Does not refer to this segment
uint32 Target, TargetDisplacement; // Contents of FIXUPP record
//uint32 Frame; // Contents of FIXUPP record
uint8 byte1, byte2; // First two bytes of subrecord
// Bitfields in subrecords
OMF_SLocat Locat; // Structure of first two bytes of FIXUP subrecord swapped = Locat field
OMF_SFixData FixData; // Structure of FixData field in FIXUP subrecord of FIXUPP record
OMF_STrdDat TrdDat; // Structure of Thread Data field in THREAD subrecord of FIXUPP record
Records[RecNum].Index = 3;
if (Records[LastDataRecord].Type2 != OMF_LEDATA && Records[RecNum].Index < Records[RecNum].End) {
// Non-empty FIXUPP record does not refer to LEDATA record
if (Records[LastDataRecord].Type2 == OMF_COMDAT) {
// COMDAT currently not supported. Ignore!
}
else if (Records[LastDataRecord].Type2 == OMF_LIDATA) {
err.submit(2311); // Error: Relocation of iterated data not supported
}
else {
err.submit(2312); // Does not refer to data record
}
continue; // Ignore this FIXUPP record
}
// Loop through entries in record
while (Records[RecNum].Index < Records[RecNum].End) {
// Read first byte
byte1 = Records[RecNum].GetByte();
if (byte1 & 0x80) {
// This is a FIXUP subrecord
//Frame = 0;
Target = 0; TargetDisplacement = 0;
// read second byte
byte2 = Records[RecNum].GetByte();
// swap bytes and put into byte12 bitfield
Locat.bytes[1] = byte1;
Locat.bytes[0] = byte2;
// Read FixData
FixData.b = Records[RecNum].GetByte();
// Read conditional fields
if (FixData.s.F == 0) {
if (FixData.s.Frame < 4) {
Records[RecNum].GetIndex();
}
}
if (FixData.s.T == 0) {
// Target specified
Target = Records[RecNum].GetIndex();
//uint32 TargetMethod = FixData.s.Target + FixData.s.P * 4;
}
else {
// Target specified in previous thread
// Does anybody still use compression of repeated fixup targets?
// I don't care to support this if it is never used
err.submit(2313); // Error message: not supported
continue;
}
if (FixData.s.P == 0) {
TargetDisplacement = Records[RecNum].GetNumeric();
}
// Get inline addend and check relocation method
if (LastDataRecordPointer && Locat.s.Offset < LastDataRecordSize) {
// Pointer to relocation source inline in raw data:
int8 * inlinep = LastDataRecordPointer + Locat.s.Offset;
switch (Locat.s.Location) { // Relocation method
case 9: case 13: // 32 bit
// The OMF format may indicate a relocation target by an
// offset stored inline in the relocation source.
// We prefer to store the target address explicitly in a
// symbol table entry.
// Add the inline offset to the explicit offset
TargetDisplacement += *(uint32*)inlinep;
// Remove the inline addend to avoid adding it twice:
// We have to do this in the new buffer TempBuf because
// the data have already been copied to TempBuf
if (*(uint32*)(TempBuf.Buf() + LastOffset + Locat.s.Offset) != *(uint32*)inlinep) {
// Check that the data in Buf() and TempBuf.Buf() are the same
err.submit(9000);
}
// Remove the inline addend to avoid adding it twice
*(uint32*)(TempBuf.Buf() + LastOffset + Locat.s.Offset) = 0;
break;
case 0: case 4: // 8 bit. Not supported
err.submit(2316, "8 bit"); break;
case 1: case 2: case 5: // 16 bit. Not supported
err.submit(2316, "16 bit"); break;
case 3: // 16+16 bit. Not supported
err.submit(2316, "16+16 bit far"); break;
case 6: case 11: // 16+32 bit. Not supported
err.submit(2316, "16+32 bit far"); break;
}
}
// Make relocation record
// Offset of relocation source
rel.VirtualAddress = Locat.s.Offset + LastOffset;
SOMFLocalSymbol locsym; // Symbol record for search in LocalSymbols table
int32 LocalSymbolsIndex; // Index into LocalSymbols table
// Relocation type: direct or EIP-relative
// (The displacement between relocation source and EIP for
// self-relative relocations is implicit in both OMF and COFF
// files. No need for correction)
rel.Type = Locat.s.M ? COFF32_RELOC_DIR32 : COFF32_RELOC_REL32;
switch (FixData.s.Target) { // = Target method modulo 4
case 0: // T0 and T4: Target = segment
// Local or public symbol. Search in LocalSymbols table
locsym.Segment = Target; // Target segment
locsym.Offset = TargetDisplacement; // Target offset including inline displacement
// Find in LocalSymbols table
LocalSymbolsIndex = LocalSymbols.Exists(locsym);
if (LocalSymbolsIndex < 0) {err.submit(9000); continue;} // Not found
// Get index into new symbol table
rel.SymbolTableIndex = LocalSymbols[LocalSymbolsIndex].NewSymtabIndex;
break;
case 1: // T1 and T5: Target = segment group
// Don't know how to handle group-relative relocation. Make error message
err.submit(2315, GetLocalName(Target));
continue;
case 2: // T2 and T6: Target = external symbol
// Translate old EXTDEF index to new symbol table index
if (Target >= ExtdefTranslation.GetNumEntries()) {
Target = 0; err.submit(2312);
continue;
}
rel.SymbolTableIndex = ExtdefTranslation[Target];
// Put addend inline in new file
if (LastOffset + Locat.s.Offset < SegmentSize) {
*(uint32*)(TempBuf.Buf() + LastOffset + Locat.s.Offset) = TargetDisplacement;
}
break;
default: // Unknown method
err.submit(2314, FixData.s.Target + FixData.s.P * 4);
}
// Store in temporary relocation table
RelocationTable.Push(&rel, SIZE_SCOFF_Relocation);
}
else {
// This is a THREAD subrecord.
// I don't think this feature for compressing fixup data is
// used any more, if it ever was. I am not supporting it here.
// Frame threads can be safely ignored. A target thread cannot
// be ignored if there is any reference to it. The error is
// reported above at the reference to a target thread, not here.
TrdDat.b = byte1; // Put byte into bitfield
if (TrdDat.s.Method < 4) { // Make sure we read this correctly, even if ignored
Records[RecNum].GetIndex(); // has index field if method < 4 ?
}
}
} // Finished loop through subrecords
if (Records[RecNum].Index != Records[RecNum].End) err.submit(1203); // Check for consistency
}
} // End of loop to search for LEDATA, LIDATA and FIXUPP records for this segment
// Transfer raw data from TempBuf to NewData buffer
FileOffset = NewData.Push(TempBuf.Buf(), SegmentSize);
// Put file offset of raw data into section header
NewSectionHeaders[SegNum].PRawData = FileOffsetData + FileOffset;
// Align relocation table by 4
NewData.Align(4);
// Transfer relocation table from RelocationTable to NewData buffer
FileOffset = NewData.Push(RelocationTable.Buf(), RelocationTable.GetDataSize());
// Put file offset of relocations into section header
NewSectionHeaders[SegNum].PRelocations = FileOffsetData + FileOffset;
// Put number of relocations into section header
NewSectionHeaders[SegNum].NRelocations = (uint16)(RelocationTable.GetNumEntries());
// Put number of relocations into symbol table auxiliary entry.
// Search for the symbol table entry for this section:
for (uint32 sym = 0; sym < NewSymbolTable.GetNumEntries(); sym++) {
if ((uint32)NewSymbolTable[sym].s.SectionNumber == DesiredSegment
&& NewSymbolTable[sym].s.StorageClass == COFF_CLASS_STATIC
&& NewSymbolTable[sym].s.NumAuxSymbols == 1) {
// Found right symbol table entry. Insert NumberOfRelocations
NewSymbolTable[sym+1].section.NumberOfRelocations = NewSectionHeaders[SegNum].NRelocations;
break; // No need to search further
}
}
} // End of loop through segments
}
void COMF2COF::CheckUnsupportedRecords() {
// Make warnings if file containes unsupported record types
uint32 RecNum; // Record number
uint32 NumComdat = 0; // Number of COMDAT records
uint32 NumComent = 0; // Number of COMENT records
// Loop through all records
for (RecNum = 0; RecNum < NumRecords; RecNum++) {
// Check record type
switch (Records[RecNum].Type2) {
case OMF_THEADR: case OMF_MODEND: case OMF_EXTDEF: case OMF_PUBDEF:
case OMF_LNAMES: case OMF_SEGDEF: case OMF_GRPDEF: case OMF_FIXUPP:
case OMF_LEDATA: case OMF_LIDATA: case OMF_COMDEF: case OMF_VERNUM:
// These record types are supported or can safely be ignored
break;
case OMF_LINNUM: case OMF_LINSYM:
// Debug records
cmd.CountDebugRemoved(); break;
case OMF_COMDAT: case OMF_LCOMDEF: case OMF_CEXTDEF:
NumComdat++; break; // Count COMDAT records
case OMF_COMENT:
NumComent++; break; // Count COMENT records
default: // Warning for unknown record type
err.submit(1212, COMF::GetRecordTypeName(Records[RecNum].Type2));
}
}
// Report number of unsupported sections found
if (NumComdat) err.submit(2305, NumComdat);
if (NumComent) err.submit(1211, NumComent);
}
void COMF2COF::MakeBinaryFile() {
// Putting sections together
uint32 i;
// Get number of symbols and sections into file header
NewFileHeader.NumberOfSymbols = NewSymbolTable.GetNumEntries();
NewFileHeader.NumberOfSections = NewSectionHeaders.GetNumEntries();
// Put file header into new file
ToFile.Push(&NewFileHeader, sizeof(NewFileHeader));
// Put section headers into new file
if (NewSectionHeaders.GetNumEntries()) {
ToFile.Push(&NewSectionHeaders[0], NewSectionHeaders.GetNumEntries() * sizeof(SCOFF_SectionHeader));
}
// Put raw data and relocation tables into new file
ToFile.Push(NewData.Buf(), NewData.GetDataSize());
// Get address of symbol table into file header
ToFile.Get<SCOFF_FileHeader>(0).PSymbolTable = ToFile.GetDataSize();
// Put symbol table into new file
for (i = 0; i < NewSymbolTable.GetNumEntries(); i++) {
ToFile.Push(&NewSymbolTable[i], SIZE_SCOFF_SymTableEntry);
}
// Insert string table size
NewStringTable.Get<uint32>(0) = NewStringTable.GetDataSize();
// Put string table into new file
ToFile.Push(NewStringTable.Buf(), NewStringTable.GetDataSize());
}