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@schmittsfn
Last active August 19, 2019 13:51
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Generates an array of strings containing info on the loaded binary images at runtime. Useful for symbolicating stack traces using the atos command for example.
// Copyright (c) 2019 sts2055
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
// The above copyright notice and this permission notice shall be included in all
// copies or substantial portions of the Software.
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
// SOFTWARE.
import Foundation
import MachO
/// Helpful links
///
/// https://stackoverflow.com/questions/5567215/how-to-determine-binary-image-architecture-at-runtime
///
/// https://github.com/apple/swift/blob/master/stdlib/private/SwiftReflectionTest/SwiftReflectionTest.swift
///
/// https://lowlevelbits.org/parsing-mach-o-files/
///
/// https://developer.apple.com/library/archive/technotes/tn2151/_index.html
struct BinaryImagesInspector {
#if arch(x86_64) || arch(arm64)
typealias MachHeader = mach_header_64
#else
typealias MachHeader = mach_header
#endif
private static let imageNamesToLog: [String]?
/// Retrieves binary infos that provide infos to be used with the atos command to symbolicate stack traces
///
/// e.g. atos -arch arm64 -o TheElements.app.dSYM/Contents/Resources/DWARF/TheElements -l 0x1000e4000 0x00000001000effdc
///
/// - Returns: An array of strings containing info on loaded binary name, its load address, architecture
static func getBinaryImagesInfo() -> [String] {
let count = _dyld_image_count()
var stringsToLog = [String]()
for i in 0..<count {
guard let dyld = _dyld_get_image_name(i) else { continue }
let dyldStr = String(cString: dyld)
let subStrings = dyldStr.split(separator: "/")
guard let imageName = subStrings.last else { continue }
if let imageNamesToLog = self.imageNamesToLog {
guard imageNamesToLog.contains(String(imageName)) else { continue }
}
guard let uncastHeader = _dyld_get_image_header(i) else { continue }
let machHeader = uncastHeader.withMemoryRebound(to: MachHeader.self, capacity: MemoryLayout<MachHeader>.size) { $0 }
guard let info = NXGetArchInfoFromCpuType(machHeader.pointee.cputype, machHeader.pointee.cpusubtype) else { continue }
guard let archName = info.pointee.name else { continue }
let uuid = getBinaryImageUUID(machHeader: machHeader)
let logStr = "\(imageName) \(machHeader.debugDescription) - \(String(cString: archName)) - \(uuid ?? "uuid not found")"
stringsToLog.append(logStr)
}
return stringsToLog
}
private static func getBinaryImageUUID(machHeader: UnsafePointer<MachHeader>) -> String? {
guard var header_ptr = UnsafePointer<UInt8>.init(bitPattern: UInt(bitPattern: machHeader)) else {
return nil
}
header_ptr += MemoryLayout<MachHeader>.size
guard var command = UnsafePointer<load_command>.init(bitPattern: UInt(bitPattern: header_ptr)) else {
return nil
}
for _ in 0..<machHeader.pointee.ncmds {
if command.pointee.cmd == LC_UUID {
guard let ucmd_ptr = UnsafePointer<uuid_command>.init(bitPattern: UInt(bitPattern: header_ptr)) else { continue }
let ucmd = ucmd_ptr.pointee
let cuuidBytes = CFUUIDBytes(byte0: ucmd.uuid.0,
byte1: ucmd.uuid.1,
byte2: ucmd.uuid.2,
byte3: ucmd.uuid.3,
byte4: ucmd.uuid.4,
byte5: ucmd.uuid.5,
byte6: ucmd.uuid.6,
byte7: ucmd.uuid.7,
byte8: ucmd.uuid.8,
byte9: ucmd.uuid.9,
byte10: ucmd.uuid.10,
byte11: ucmd.uuid.11,
byte12: ucmd.uuid.12,
byte13: ucmd.uuid.13,
byte14: ucmd.uuid.14,
byte15: ucmd.uuid.15)
guard let cuuid = CFUUIDCreateFromUUIDBytes(kCFAllocatorDefault, cuuidBytes) else {
return nil
}
let suuid = CFUUIDCreateString(kCFAllocatorDefault, cuuid)
let encoding = CFStringGetFastestEncoding(suuid)
guard let cstr = CFStringGetCStringPtr(suuid, encoding) else {
return nil
}
let str = String(cString: cstr)
return str
}
header_ptr += Int(command.pointee.cmdsize)
guard let newCommand = UnsafePointer<load_command>.init(bitPattern: UInt(bitPattern: header_ptr)) else { continue }
command = newCommand
}
return nil
}
}
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