private void BuildSymbolLookup()
{
var sw = System.Diagnostics.Stopwatch.StartNew();
uint totalSymbols = 0;
// build information on all loaded images
mImages = new ImageSymbolInfo[_dyld_image_count()];
for (uint i = 0; i < mImages.Length; i++)
{
GetImageSymbolInfo(i, ref mImages[i]);
totalSymbols += mImages[i].SymbolTable.nsyms + (uint)SpecialSymbol.Total;
}
// create symbol lookup table
mSymbolCount = 0;
mSymbolAddressTable = new Address[totalSymbols];
mSymbolIdTable = new int[totalSymbols];
// add symbol info from all images
for (uint i = 0; i < mImages.Length; i++)
{
// int count = mSymbolCount;
AddImageSymbols(ref mImages[i]);
AddImageSectionsAsSymbols(ref mImages[i]);
// Console.WriteLine("Telemetry: Image[{0,3}] Symbols:{1,6} Name:{2}", i, mSymbolCount - count, mImages[i].Name);
}
// sort symbols by address
Array.Sort(mSymbolAddressTable, mSymbolIdTable, 0, mSymbolCount);
Console.WriteLine("Telemetry: Built symbol table (SymbolCount:{0} Time:{1})", mSymbolCount, sw.Elapsed);
}
private unsafe void AddImageSectionsAsSymbols(ref ImageSymbolInfo image)
{
// get image header
IntPtr ptr = _dyld_get_image_header(image.Index);
var hdr = (mach_header)Marshal.PtrToStructure(ptr, typeof(mach_header));
// check header magic number
if (hdr.magic != MH_MAGIC)
{
// unsupported header type
return;
}
// get pointer to first load command
ptr += sizeof(mach_header);
// parse image load commands
for (int j = 0; j < hdr.ncmds; j++)
{
// get load_command
var lc = (load_command)Marshal.PtrToStructure(ptr, typeof(load_command));
if (lc.cmd == LC_SEGMENT)
{
var segment = (segment_command)Marshal.PtrToStructure(ptr, typeof(segment_command));
// get segment start and end
Address segmentStart = (Address)(image.Slide + (int)segment.vmaddr);
Address segmentEnd = segmentStart + segment.filesize;
// mark the start and end of this image using special symbols
AddSymbol(segmentStart, image.Index, image.SymbolTable.nsyms + (uint)SpecialSymbol.SegmentStart);
AddSymbol(segmentEnd, image.Index, image.SymbolTable.nsyms + (uint)SpecialSymbol.SegmentEnd);
}
// next command
ptr += (int)lc.cmdsize;
}
}
private unsafe void GetImageSymbolInfo(uint imageIndex, ref ImageSymbolInfo image)
{
// get image index
image.Index = imageIndex;
// get image name
image.FullName = Marshal.PtrToStringAnsi(_dyld_get_image_name(imageIndex));
/// get short name
image.Name = System.IO.Path.GetFileNameWithoutExtension(image.FullName);
// get image 'slide'
image.Slide = _dyld_get_image_vmaddr_slide(imageIndex);
// get image header
IntPtr ptr = _dyld_get_image_header(imageIndex);
var hdr = (mach_header)Marshal.PtrToStructure(ptr, typeof(mach_header));
// check header magic number
if (hdr.magic != MH_MAGIC)
{
// unsupported header type
return;
}
// get pointer to first load command
ptr += sizeof(mach_header);
// parse image load commands
for (int j = 0; j < hdr.ncmds; j++)
{
// get load_command
var lc = (load_command)Marshal.PtrToStructure(ptr, typeof(load_command));
if (lc.cmd == LC_SEGMENT)
{
var segment = (segment_command)Marshal.PtrToStructure(ptr, typeof(segment_command));
// find linkedit segment
if (segment.segname.Contains("LINKEDIT"))
{
image.LinkEdit = segment;
}
}
else if (lc.cmd == LC_SYMTAB)
{
// symtab command
image.SymbolTable = (symtab_command)Marshal.PtrToStructure(ptr, typeof(symtab_command));
}
// next command
ptr += (int)lc.cmdsize;
}
}
private unsafe void AddImageSymbols(ref ImageSymbolInfo image)
{
IntPtr baseaddr = image.Slide + (int)(image.LinkEdit.vmaddr - image.LinkEdit.fileoff);
IntPtr symaddr = baseaddr + (int)image.SymbolTable.symoff;
for (int symbolIndex = 0; symbolIndex < image.SymbolTable.nsyms; symbolIndex++)
{
nlist n = (nlist)Marshal.PtrToStructure(symaddr + symbolIndex * sizeof(nlist), typeof(nlist));
// see if this is a valid named symbol using magic flags
if ((n.n_value != 0) && (n.n_type & 0xE0) == 0 && (n.n_type & 0xE) == 0xE)
{
// get address of symbol
IntPtr address = image.Slide + (int)n.n_value;
AddSymbol((Address)address, image.Index, (uint)symbolIndex);
}
}
}
private void BuildSymbolLookup()
{
var sw = System.Diagnostics.Stopwatch.StartNew();
uint totalSymbols = 0;
// build information on all loaded images
mImages = new ImageSymbolInfo[_dyld_image_count ()];
for (uint i=0; i < mImages.Length; i++) {
GetImageSymbolInfo(i, ref mImages[i]);
totalSymbols += mImages[i].SymbolTable.nsyms + (uint)SpecialSymbol.Total;
}
// create symbol lookup table
mSymbolCount = 0;
mSymbolAddressTable = new Address[totalSymbols];
mSymbolIdTable = new int[totalSymbols];
// add symbol info from all images
for (uint i=0; i < mImages.Length; i++) {
// int count = mSymbolCount;
AddImageSymbols(ref mImages[i]);
AddImageSectionsAsSymbols(ref mImages[i]);
// Console.WriteLine("Telemetry: Image[{0,3}] Symbols:{1,6} Name:{2}", i, mSymbolCount - count, mImages[i].Name);
}
// sort symbols by address
Array.Sort (mSymbolAddressTable, mSymbolIdTable, 0, mSymbolCount);
Console.WriteLine("Telemetry: Built symbol table (SymbolCount:{0} Time:{1})", mSymbolCount, sw.Elapsed);
}
private unsafe void GetImageSymbolInfo(uint imageIndex, ref ImageSymbolInfo image)
{
// get image index
image.Index = imageIndex;
// get image name
image.FullName = Marshal.PtrToStringAnsi (_dyld_get_image_name(imageIndex));
/// get short name
image.Name = System.IO.Path.GetFileNameWithoutExtension(image.FullName);
// get image 'slide'
image.Slide = _dyld_get_image_vmaddr_slide (imageIndex);
// get image header
IntPtr ptr = _dyld_get_image_header (imageIndex);
var hdr = (mach_header)Marshal.PtrToStructure (ptr, typeof(mach_header));
// check header magic number
if (hdr.magic != MH_MAGIC) {
// unsupported header type
return;
}
// get pointer to first load command
ptr += sizeof(mach_header);
// parse image load commands
for (int j=0; j < hdr.ncmds; j++) {
// get load_command
var lc = (load_command)Marshal.PtrToStructure (ptr, typeof(load_command));
if (lc.cmd == LC_SEGMENT) {
var segment = (segment_command)Marshal.PtrToStructure (ptr, typeof(segment_command));
// find linkedit segment
if (segment.segname.Contains ("LINKEDIT")) {
image.LinkEdit = segment;
}
} else if (lc.cmd == LC_SYMTAB) {
// symtab command
image.SymbolTable = (symtab_command)Marshal.PtrToStructure (ptr, typeof(symtab_command));
}
// next command
ptr += (int)lc.cmdsize;
}
}
private unsafe void AddImageSectionsAsSymbols(ref ImageSymbolInfo image)
{
// get image header
IntPtr ptr = _dyld_get_image_header (image.Index);
var hdr = (mach_header)Marshal.PtrToStructure (ptr, typeof(mach_header));
// check header magic number
if (hdr.magic != MH_MAGIC) {
// unsupported header type
return;
}
// get pointer to first load command
ptr += sizeof(mach_header);
// parse image load commands
for (int j=0; j < hdr.ncmds; j++) {
// get load_command
var lc = (load_command)Marshal.PtrToStructure (ptr, typeof(load_command));
if (lc.cmd == LC_SEGMENT) {
var segment = (segment_command)Marshal.PtrToStructure (ptr, typeof(segment_command));
// get segment start and end
Address segmentStart = (Address)(image.Slide + (int)segment.vmaddr);
Address segmentEnd = segmentStart + segment.filesize;
// mark the start and end of this image using special symbols
AddSymbol(segmentStart, image.Index, image.SymbolTable.nsyms + (uint)SpecialSymbol.SegmentStart);
AddSymbol(segmentEnd, image.Index, image.SymbolTable.nsyms + (uint)SpecialSymbol.SegmentEnd);
}
// next command
ptr += (int)lc.cmdsize;
}
}
private unsafe void AddImageSymbols(ref ImageSymbolInfo image)
{
IntPtr baseaddr = image.Slide + (int)(image.LinkEdit.vmaddr - image.LinkEdit.fileoff);
IntPtr symaddr = baseaddr + (int)image.SymbolTable.symoff;
for (int symbolIndex=0; symbolIndex < image.SymbolTable.nsyms; symbolIndex++) {
nlist n = (nlist)Marshal.PtrToStructure (symaddr + symbolIndex * sizeof(nlist), typeof(nlist));
// see if this is a valid named symbol using magic flags
if ((n.n_value != 0) && (n.n_type&0xE0) == 0 && (n.n_type&0xE) == 0xE) {
// get address of symbol
IntPtr address = image.Slide + (int)n.n_value;
AddSymbol((Address)address, image.Index, (uint)symbolIndex);
}
}
}
