Fix LLDB RSP client to decode '$O' packets incorrectly

Character with ASCII code 0 is incorrectly treated by LLDB as the end of RSP packet. The left of the debugger server output is silently ignored. Patch from evgeny.leviant@gmail.com Reviewed by: clayborg Subscribers: lldb-commits Differential Revision: http://reviews.llvm.org/D12523 llvm-svn: 247908
llvm · Sep 17, 2015 · 554a857 · 554a857
1 parent 0537f41
commit 554a857
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Showing 3 changed files with 21 additions and 5 deletions.
diff --git a/lldb/include/lldb/Utility/StringExtractor.h b/lldb/include/lldb/Utility/StringExtractor.h
@@ -114,6 +114,9 @@ class StringExtractor
     uint8_t
     GetHexU8 (uint8_t fail_value = 0, bool set_eof_on_fail = true);
 
+    bool
+    GetHexU8Ex (uint8_t& ch, bool set_eof_on_fail = true);
+
     bool
     GetNameColonValue (std::string &name, std::string &value);
 

diff --git a/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationClient.cpp b/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationClient.cpp
@@ -1262,9 +1262,13 @@ GDBRemoteCommunicationClient::SendContinuePacketAndWaitForResponse
                         got_async_packet = true;
                         std::string inferior_stdout;
                         inferior_stdout.reserve(response.GetBytesLeft () / 2);
-                        char ch;
-                        while ((ch = response.GetHexU8()) != '\0')
-                            inferior_stdout.append(1, ch);
+
+                        uint8_t ch;
+                        while (response.GetHexU8Ex(ch))
+                        {
+                            if (ch != 0)
+                                inferior_stdout.append(1, (char)ch);
+                        }
                         process->AppendSTDOUT (inferior_stdout.c_str(), inferior_stdout.size());
                     }
                     break;

diff --git a/lldb/source/Utility/StringExtractor.cpp b/lldb/source/Utility/StringExtractor.cpp
@@ -124,15 +124,24 @@ StringExtractor::DecodeHexU8()
 //----------------------------------------------------------------------
 uint8_t
 StringExtractor::GetHexU8 (uint8_t fail_value, bool set_eof_on_fail)
+{
+    GetHexU8Ex(fail_value, set_eof_on_fail);
+    return fail_value;
+}
+
+bool
+StringExtractor::GetHexU8Ex (uint8_t& ch, bool set_eof_on_fail)
 {
     int byte = DecodeHexU8();
     if (byte == -1)
     {
         if (set_eof_on_fail || m_index >= m_packet.size())
             m_index = UINT64_MAX;
-        return fail_value;
+        // ch should not be changed in case of failure
+        return false;
     }
-    return (uint8_t)byte;
+    ch = (uint8_t)byte;
+    return true;
 }
 
 uint32_t