linux variant of nbl::system::isDebuggerAttached

Author: YasInvolved

include/nbl/system/CSystemLinux.h

@@ -16,6 +16,9 @@ class CSystemLinux final : public ISystemPOSIX
 
 		NBL_API2 SystemInfo getSystemInfo() const override;
 };
+
+bool isDebuggerAttached();
+
 #endif
 }
 

src/nbl/system/CSystemLinux.cpp

@@ -6,6 +6,9 @@ using namespace nbl::system;
 #ifdef _NBL_PLATFORM_LINUX_
 
 #include <sys/sysinfo.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <unistd.h>
 ISystem::SystemInfo CSystemLinux::getSystemInfo() const
 {
     SystemInfo info;
@@ -26,4 +29,37 @@ ISystem::SystemInfo CSystemLinux::getSystemInfo() const
 
     return info;
 }
+
+bool isDebuggerAttached()
+{
+   constexpr char tracerPidStr[] = "TracerPid:";
+   char buf[4096];
+
+   const int status = open("/proc/self/status");
+   if (status == -1)
+      return false;
+
+   const size_t numRead = read(status, static_cast<void*>(buf), sizeof(buf) - 1);
+   close(status);
+
+   buf[numRead] = '\0';
+   const auto offset = strstr(buf, tracerPidStr);
+   if (not offset)
+      return false;
+
+   // few helper lambdas
+   auto isSpace = [](char c) { return c == ' '; };
+   auto isDigit = [](char c) { return c >= '0' && c <= '9'; };
+
+   for (const char* cPtr = offset + sizeof(tracerPidStr) - 1; cPtr <= buf + numRead; cPtr++)
+   {
+      if (isSpace(*cPtr))
+         continue;
+      else
+         return isDigit(*cPtr) && *cPtr != '0';
+   }
+
+   return false;
+}
+
 #endif