<div dir="ltr">Hey Matthew,<div><br></div><div>That 0 parameter to strtoul doesn't quite work like that. The 0 indicates that the input character string determines how the base is interpreted. So a 0x{hex} will get interpreted base 16, a standard non-zero-leading set of decimal numbers is base 10, and a 0{octal} is octal.</div>
<div><br></div><div>See this snippet:</div><div>===</div><div><div>#include <cstdlib></div><div>#include <iostream></div><div><br></div><div>int main(int argc, char **argv)</div><div>{</div><div> const unsigned long val1 = std::strtoul("0x10", nullptr, 0);</div>
<div> const unsigned long val2 = std::strtoul("16", nullptr, 0);</div><div> const unsigned long val3 = std::strtoul("020", nullptr, 0);</div><div><br></div><div> std::cout << "val1: " << val1 << std::endl;</div>
<div> std::cout << "val2: " << val2 << std::endl;</div><div> std::cout << "val3: " << val3 << std::endl;</div><div><br></div><div> if ((val1 == val2) && (val2 == val3) && (val1 == val3))</div>
<div> std::cout << "equal!" << std::endl;</div><div> else</div><div> std::cout << "different!" << std::endl;</div><div>}</div><div>===</div><div><br></div><div>
If you compile and run that with a command line something like this:</div><div><br></div><div><div>tfiala-macbookpro:cpp tfiala$ clang -std=c++11 -lc++ -o strtoul strtoul.cpp</div><div>tfiala-macbookpro:cpp tfiala$ ./strtoul</div>
<div>val1: 16</div><div>val2: 16</div><div>val3: 16</div><div>equal!</div><div>tfiala-macbookpro:cpp tfiala$ </div></div><div><br></div><div>You'll see that 3 different strings with the same call to strtoul all get interpreted as the same integer value - namely decimal 16. The string input is what determines the base.</div>
<div><br></div><div>So, it comes back to how is qHostInfo written in this case. Going back to RNBRemote.cpp, you'll see here in HandlePacket_qHostInfo():</div><div><br></div><div><div> </div><div> strm << "cputype:" << std::dec << cputype << ';';</div>
<div> strm << "cpusubtype:" << std::dec << cpusubtype << ';';<br></div></div></div><div><br></div><div>they're getting written as decimal.</div><div><br></div><div>And in GDBRemoteCommunicationServer.cpp where lldb-platform sends the content, it's also written as decimal (in Handle_qHostInfo()):</div>
<div><br></div><div><div> if (cpu != LLDB_INVALID_CPUTYPE)</div><div> response.Printf ("cputype:%u;", cpu);</div><div> if (sub != LLDB_INVALID_CPUTYPE)</div><div> response.Printf ("cpusubtype:%u;", sub);</div>
<div><br></div></div><div>Since they are written as decimal numbers, that's how the client code will interpret it. And so I believe the docs are correct in that regard for qHostInfo.</div><div><br></div><div>-Todd</div>
</div><div class="gmail_extra"><br><br><div class="gmail_quote">On Wed, Jun 11, 2014 at 10:10 PM, Matthew Gardiner <span dir="ltr"><<a href="mailto:mg11@csr.com" target="_blank">mg11@csr.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div class="">Todd Fiala wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
Hey Matthew,<br>
<br>
> 1. I've changed the base of cputype and cpusubtype to reflect the fact that the code assumes base-16, and furthermore to be consistent with qProcessInfo.<br>
<br>
I'm looking at the debugserver code (RNBRemote.cpp) and lldb-platform/llgs code (GDBRemoteCommunicationServer.<u></u>cpp) that produce those values. The cputype and cpusubtype all are being written decimal as far as a I read it. What context are you seeing hexadecimal?<br>
<br>
Thanks!<br>
<br>
-Todd<br>
</blockquote>
<br></div>
Hi Todd,<br>
<br>
I'm seeing the context as being assumed as hex in the parsing of the *inbound* qHostInfo in lldb.<br>
<br>
Check out: GDBRemoteCommunicationClient::<u></u>GetHostInfo in GDBRemoteCommunicationClient.<u></u>cpp<br>
<br>
see this code:<br>
<br>
if (name.compare("cputype") == 0)<br>
{<br>
// exception type in big endian hex<br>
cpu = Args::StringToUInt32 (value.c_str(), LLDB_INVALID_CPUTYPE, 0);<br>
...<br>
}<br>
else if (name.compare("cpusubtype") == 0)<br>
{<br>
// exception count in big endian hex<br>
sub = Args::StringToUInt32 (value.c_str(), 0, 0);<br>
..<br>
}<br>
<br>
the third argument to StringToUInt32 is 0, which is passed to strtoul, which is interpreted as base-16. Thus the parsing side in lldb assumes these are base-16.<br>
<br>
A side issue is that the documentation to qProcessInfo in lldb-gdb-remote.txt which says base-16 for these same datas.<br>
<br>
So we have inconsistency in the docs between qProcessInfo and qHostInfo, and a bug between the sender and receiver of qHostInfo.<br>
<br>
thanks<br>
Matt<div class="HOEnZb"><div class="h5"><br>
<br>
<br>
<br>
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<td nowrap style="border-top-style:solid;border-top-color:rgb(213,15,37);border-top-width:2px">Todd Fiala |</td><td nowrap style="border-top-style:solid;border-top-color:rgb(51,105,232);border-top-width:2px"> Software Engineer |</td>
<td nowrap style="border-top-style:solid;border-top-color:rgb(0,153,57);border-top-width:2px"> <a href="mailto:tfiala@google.com" style="color:rgb(17,85,204)" target="_blank"><span style="background-color:rgb(255,255,204);color:rgb(34,34,34);background-repeat:initial initial">tfiala@google.com</span></a> |</td>
<td nowrap style="border-top-style:solid;border-top-color:rgb(238,178,17);border-top-width:2px"><font color="#1155cc"> <a>650-943-3180</a></font></td></tr></tbody></table><br></div>
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