lldb: deal with non-portable PTRACE-related constants

[pawelo]

Summary

These PTRACE-related enum values are not present everywhere; their presence is denoted by certain preprocessor definitions in sys/ptrace.h that we can check.

[tfiala]

Missed this one earlier this month. I'll have a look at this now.

[tfiala]

LGTM.

Although missing the support of ReadGPR() and ReadFPR() methods will reduce the functionality available - without these I think the inferior process will lose the ability to execute expressions within the process as full register state cannot be saved.

Note I'll be adding this and the previous cross-compile-related changes to the llgs branch as well - NativeProcessLinux.cpp in that branch operates similar to ProcessMonitor.cpp here.

[tfiala]

svn commit
Sending source/Plugins/Process/Linux/ProcessMonitor.cpp
Transmitting file data .
Committed revision 211503.

source/Plugins/Process/Linux/ProcessMonitor.cpp

if (verbose_log)
                 break;
             }
         case PTRACE_POKEUSER:
             {
                 DisplayBytes(buf, &data, 8);
                 verbose_log->Printf("PTRACE_POKEUSER %s", buf.GetData());
                 break;
             }
+#ifdef PT_SETREGS
         case PTRACE_SETREGS:
             {
                 DisplayBytes(buf, data, data_size);
                 verbose_log->Printf("PTRACE_SETREGS %s", buf.GetData());
                 break;
             }
+#endif
+#ifdef PT_SETFPREGS
         case PTRACE_SETFPREGS:
             {
                 DisplayBytes(buf, data, data_size);
                 verbose_log->Printf("PTRACE_SETFPREGS %s", buf.GetData());
                 break;
             }
+#endif
         case PTRACE_SETSIGINFO:
             {
                 DisplayBytes(buf, data, sizeof(siginfo_t));
                 verbose_log->Printf("PTRACE_SETSIGINFO %s", buf.GetData());
                 break;
             }
         case PTRACE_SETREGSET:
             {
private:
     void *m_buf;
     size_t m_buf_size;
     bool &m_result;
 };
 
 void
 ReadGPROperation::Execute(ProcessMonitor *monitor)
 {
+#ifdef PT_GETREGS
     if (PTRACE(PTRACE_GETREGS, m_tid, NULL, m_buf, m_buf_size) < 0)
         m_result = false;
     else
         m_result = true;
+#else
+    m_result = false;
+#endif
 }
 
 //------------------------------------------------------------------------------
 /// @class ReadFPROperation
 /// @brief Implements ProcessMonitor::ReadFPR.
 class ReadFPROperation : public Operation
 {
 public:
     ReadFPROperation(lldb::tid_t tid, void *buf, size_t buf_size, bool &result)
         : m_tid(tid), m_buf(buf), m_buf_size(buf_size), m_result(result)
         { }
 
     void Execute(ProcessMonitor *monitor);
 
 private:
     lldb::tid_t m_tid;
     void *m_buf;
     size_t m_buf_size;
     bool &m_result;
 };
 
 void
 ReadFPROperation::Execute(ProcessMonitor *monitor)
 {
+#ifdef PT_GETFPREGS
     if (PTRACE(PTRACE_GETFPREGS, m_tid, NULL, m_buf, m_buf_size) < 0)
         m_result = false;
     else
         m_result = true;
+#else
+    m_result = false;
+#endif
 }
 
 //------------------------------------------------------------------------------
 /// @class ReadRegisterSetOperation
 /// @brief Implements ProcessMonitor::ReadRegisterSet.
 class ReadRegisterSetOperation : public Operation
 {
 public:
private:
     void *m_buf;
     size_t m_buf_size;
     bool &m_result;
 };
 
 void
 WriteGPROperation::Execute(ProcessMonitor *monitor)
 {
+#ifdef PT_SETREGS
     if (PTRACE(PTRACE_SETREGS, m_tid, NULL, m_buf, m_buf_size) < 0)
         m_result = false;
     else
         m_result = true;
+#else
+    m_result = false;
+#endif
 }
 
 //------------------------------------------------------------------------------
 /// @class WriteFPROperation
 /// @brief Implements ProcessMonitor::WriteFPR.
 class WriteFPROperation : public Operation
 {
 public:
     WriteFPROperation(lldb::tid_t tid, void *buf, size_t buf_size, bool &result)
         : m_tid(tid), m_buf(buf), m_buf_size(buf_size), m_result(result)
         { }
 
     void Execute(ProcessMonitor *monitor);
 
 private:
     lldb::tid_t m_tid;
     void *m_buf;
     size_t m_buf_size;
     bool &m_result;
 };
 
 void
 WriteFPROperation::Execute(ProcessMonitor *monitor)
 {
+#ifdef PT_SETFPREGS
     if (PTRACE(PTRACE_SETFPREGS, m_tid, NULL, m_buf, m_buf_size) < 0)
         m_result = false;
     else
         m_result = true;
+#else
+    m_result = false;
+#endif
 }
 
 //------------------------------------------------------------------------------
 /// @class WriteRegisterSetOperation
 /// @brief Implements ProcessMonitor::WriteRegisterSet.
 class WriteRegisterSetOperation : public Operation
 {
 public: