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Diffstat (limited to 'indra/llcommon/llleap.cpp')
| -rw-r--r-- | indra/llcommon/llleap.cpp | 459 |
1 files changed, 459 insertions, 0 deletions
diff --git a/indra/llcommon/llleap.cpp b/indra/llcommon/llleap.cpp new file mode 100644 index 0000000000..0a57ef1c48 --- /dev/null +++ b/indra/llcommon/llleap.cpp @@ -0,0 +1,459 @@ +/** + * @file llleap.cpp + * @author Nat Goodspeed + * @date 2012-02-20 + * @brief Implementation for llleap. + * + * $LicenseInfo:firstyear=2012&license=viewerlgpl$ + * Copyright (c) 2012, Linden Research, Inc. + * $/LicenseInfo$ + */ + +// Precompiled header +#include "linden_common.h" +// associated header +#include "llleap.h" +// STL headers +#include <sstream> +#include <algorithm> +// std headers +// external library headers +#include <boost/bind.hpp> +#include <boost/scoped_ptr.hpp> +#include <boost/tokenizer.hpp> +// other Linden headers +#include "llerror.h" +#include "llstring.h" +#include "llprocess.h" +#include "llevents.h" +#include "stringize.h" +#include "llsdutil.h" +#include "llsdserialize.h" +#include "llerrorcontrol.h" +#include "lltimer.h" +#include "lluuid.h" +#include "llleaplistener.h" + +#if LL_MSVC +#pragma warning (disable : 4355) // 'this' used in initializer list: yes, intentionally +#endif + +LLLeap::LLLeap() {} +LLLeap::~LLLeap() {} + +class LLLeapImpl: public LLLeap +{ + LOG_CLASS(LLLeap); +public: + // Called only by LLLeap::create() + LLLeapImpl(const std::string& desc, const std::vector<std::string>& plugin): + // We might reassign mDesc in the constructor body if it's empty here. + mDesc(desc), + // We expect multiple LLLeapImpl instances. Definitely tweak + // mDonePump's name for uniqueness. + mDonePump("LLLeap", true), + // Troubling thought: what if one plugin intentionally messes with + // another plugin? LLEventPump names are in a single global namespace. + // Try to make that more difficult by generating a UUID for the reply- + // pump name -- so it should NOT need tweaking for uniqueness. + mReplyPump(LLUUID::generateNewID().asString()), + mExpect(0), + mPrevFatalFunction(LLError::getFatalFunction()), + // Instantiate a distinct LLLeapListener for this plugin. (Every + // plugin will want its own collection of managed listeners, etc.) + // Pass it a callback to our connect() method, so it can send events + // from a particular LLEventPump to the plugin without having to know + // this class or method name. + mListener(new LLLeapListener(boost::bind(&LLLeapImpl::connect, this, _1, _2))) + { + // Rule out empty vector + if (plugin.empty()) + { + throw Error("no plugin command"); + } + + // Don't leave desc empty either, but in this case, if we weren't + // given one, we'll fake one. + if (desc.empty()) + { + mDesc = LLProcess::basename(plugin[0]); + // how about a toLower() variant that returns the transformed string?! + std::string desclower(mDesc); + LLStringUtil::toLower(desclower); + // If we're running a Python script, use the script name for the + // desc instead of just 'python'. Arguably we should check for + // more different interpreters as well, but there's a reason to + // notice Python specially: we provide Python LLSD serialization + // support, so there's a pretty good reason to implement plugins + // in that language. + if (plugin.size() >= 2 && (desclower == "python" || desclower == "python.exe")) + { + mDesc = LLProcess::basename(plugin[1]); + } + } + + // Listen for child "termination" right away to catch launch errors. + mDonePump.listen("LLLeap", boost::bind(&LLLeapImpl::bad_launch, this, _1)); + + // Okay, launch child. + LLProcess::Params params; + params.desc = mDesc; + std::vector<std::string>::const_iterator pi(plugin.begin()), pend(plugin.end()); + params.executable = *pi++; + for ( ; pi != pend; ++pi) + { + params.args.add(*pi); + } + params.files.add(LLProcess::FileParam("pipe")); // stdin + params.files.add(LLProcess::FileParam("pipe")); // stdout + params.files.add(LLProcess::FileParam("pipe")); // stderr + params.postend = mDonePump.getName(); + mChild = LLProcess::create(params); + // If that didn't work, no point in keeping this LLLeap object. + if (! mChild) + { + throw Error(STRINGIZE("failed to run " << mDesc)); + } + + // Okay, launch apparently worked. Change our mDonePump listener. + mDonePump.stopListening("LLLeap"); + mDonePump.listen("LLLeap", boost::bind(&LLLeapImpl::done, this, _1)); + + // Child might pump large volumes of data through either stdout or + // stderr. Don't bother copying all that data into notification event. + LLProcess::ReadPipe + &childout(mChild->getReadPipe(LLProcess::STDOUT)), + &childerr(mChild->getReadPipe(LLProcess::STDERR)); + childout.setLimit(20); + childerr.setLimit(20); + + // Serialize any event received on mReplyPump to our child's stdin. + mStdinConnection = connect(mReplyPump, "LLLeap"); + + // Listening on stdout is stateful. In general, we're either waiting + // for the length prefix or waiting for the specified length of data. + // We address that with two different listener methods -- one of which + // is blocked at any given time. + mStdoutConnection = childout.getPump() + .listen("prefix", boost::bind(&LLLeapImpl::rstdout, this, _1)); + mStdoutDataConnection = childout.getPump() + .listen("data", boost::bind(&LLLeapImpl::rstdoutData, this, _1)); + mBlocker.reset(new LLEventPump::Blocker(mStdoutDataConnection)); + + // Log anything sent up through stderr. When a typical program + // encounters an error, it writes its error message to stderr and + // terminates with nonzero exit code. In particular, the Python + // interpreter behaves that way. More generally, though, a plugin + // author can log whatever s/he wants to the viewer log using stderr. + mStderrConnection = childerr.getPump() + .listen("LLLeap", boost::bind(&LLLeapImpl::rstderr, this, _1)); + + // For our lifespan, intercept any LL_ERRS so we can notify plugin + LLError::setFatalFunction(boost::bind(&LLLeapImpl::fatalFunction, this, _1)); + + // Send child a preliminary event reporting our own reply-pump name -- + // which would otherwise be pretty tricky to guess! + wstdin(mReplyPump.getName(), + LLSDMap + ("command", mListener->getName()) + // Include LLLeap features -- this may be important for child to + // construct (or recognize) current protocol. + ("features", LLLeapListener::getFeatures())); + } + + // Normally we'd expect to arrive here only via done() + virtual ~LLLeapImpl() + { + LL_DEBUGS("LLLeap") << "destroying LLLeap(\"" << mDesc << "\")" << LL_ENDL; + // Restore original FatalFunction + LLError::setFatalFunction(mPrevFatalFunction); + } + + // Listener for failed launch attempt + bool bad_launch(const LLSD& data) + { + LL_WARNS("LLLeap") << data["string"].asString() << LL_ENDL; + return false; + } + + // Listener for child-process termination + bool done(const LLSD& data) + { + // Log the termination + LL_INFOS("LLLeap") << data["string"].asString() << LL_ENDL; + + // Any leftover data at this moment are because protocol was not + // satisfied. Possibly the child was interrupted in the middle of + // sending a message, possibly the child didn't flush stdout before + // terminating, possibly it's just garbage. Log its existence but + // discard it. + LLProcess::ReadPipe& childout(mChild->getReadPipe(LLProcess::STDOUT)); + if (childout.size()) + { + LLProcess::ReadPipe::size_type + peeklen((std::min)(LLProcess::ReadPipe::size_type(50), childout.size())); + LL_WARNS("LLLeap") << "Discarding final " << childout.size() << " bytes: " + << childout.peek(0, peeklen) << "..." << LL_ENDL; + } + + // Kill this instance. MUST BE LAST before return! + delete this; + return false; + } + + // Listener for events on mReplyPump: send to child stdin + bool wstdin(const std::string& pump, const LLSD& data) + { + LLSD packet(LLSDMap("pump", pump)("data", data)); + + std::ostringstream buffer; + buffer << LLSDNotationStreamer(packet); + +/*==========================================================================*| + // DEBUGGING ONLY: don't copy str() if we can avoid it. + std::string strdata(buffer.str()); + if (std::size_t(buffer.tellp()) != strdata.length()) + { + LL_ERRS("LLLeap") << "tellp() -> " << buffer.tellp() << " != " + << "str().length() -> " << strdata.length() << LL_ENDL; + } + // DEBUGGING ONLY: reading back is terribly inefficient. + std::istringstream readback(strdata); + LLSD echo; + LLPointer<LLSDParser> parser(new LLSDNotationParser()); + S32 parse_status(parser->parse(readback, echo, strdata.length())); + if (parse_status == LLSDParser::PARSE_FAILURE) + { + LL_ERRS("LLLeap") << "LLSDNotationParser() cannot parse output of " + << "LLSDNotationStreamer()" << LL_ENDL; + } + if (! llsd_equals(echo, packet)) + { + LL_ERRS("LLLeap") << "LLSDNotationParser() produced different LLSD " + << "than passed to LLSDNotationStreamer()" << LL_ENDL; + } +|*==========================================================================*/ + + LL_DEBUGS("EventHost") << "Sending: " << buffer.tellp() << ':'; + std::string::size_type truncate(80); + if (buffer.tellp() <= truncate) + { + LL_CONT << buffer.str(); + } + else + { + LL_CONT << buffer.str().substr(0, truncate) << "..."; + } + LL_CONT << LL_ENDL; + + LLProcess::WritePipe& childin(mChild->getWritePipe(LLProcess::STDIN)); + childin.get_ostream() << buffer.tellp() << ':' << buffer.str() << std::flush; + return false; + } + + // Initial state of stateful listening on child stdout: wait for a length + // prefix, followed by ':'. + bool rstdout(const LLSD& data) + { + LLProcess::ReadPipe& childout(mChild->getReadPipe(LLProcess::STDOUT)); + // It's possible we got notified of a couple digit characters without + // seeing the ':' -- unlikely, but still. Until we see ':', keep + // waiting. + if (childout.contains(':')) + { + std::istream& childstream(childout.get_istream()); + // Saw ':', read length prefix and store in mExpect. + size_t expect; + childstream >> expect; + int colon(childstream.get()); + if (colon != ':') + { + // Protocol failure. Clear out the rest of the pending data in + // childout (well, up to a max length) to log what was wrong. + LLProcess::ReadPipe::size_type + readlen((std::min)(childout.size(), LLProcess::ReadPipe::size_type(80))); + bad_protocol(STRINGIZE(expect << char(colon) << childout.read(readlen))); + } + else + { + // Saw length prefix, saw colon, life is good. Now wait for + // that length of data to arrive. + mExpect = expect; + LL_DEBUGS("LLLeap") << "got length, waiting for " + << mExpect << " bytes of data" << LL_ENDL; + // Block calls to this method; resetting mBlocker unblocks + // calls to the other method. + mBlocker.reset(new LLEventPump::Blocker(mStdoutConnection)); + // Go check if we've already received all the advertised data. + if (childout.size()) + { + LLSD updata(data); + updata["len"] = LLSD::Integer(childout.size()); + rstdoutData(updata); + } + } + } + else if (childout.contains('\n')) + { + // Since this is the initial listening state, this is where we'd + // arrive if the child isn't following protocol at all -- say + // because the user specified 'ls' or some darn thing. + bad_protocol(childout.getline()); + } + return false; + } + + // State in which we listen on stdout for the specified length of data to + // arrive. + bool rstdoutData(const LLSD& data) + { + LLProcess::ReadPipe& childout(mChild->getReadPipe(LLProcess::STDOUT)); + // Until we've accumulated the promised length of data, keep waiting. + if (childout.size() >= mExpect) + { + // Ready to rock and roll. + LL_DEBUGS("LLLeap") << "needed " << mExpect << " bytes, got " + << childout.size() << ", parsing LLSD" << LL_ENDL; + LLSD data; + LLPointer<LLSDParser> parser(new LLSDNotationParser()); + S32 parse_status(parser->parse(childout.get_istream(), data, mExpect)); + if (parse_status == LLSDParser::PARSE_FAILURE) + { + bad_protocol("unparseable LLSD data"); + } + else if (! (data.isMap() && data["pump"].isString() && data.has("data"))) + { + // we got an LLSD object, but it lacks required keys + bad_protocol("missing 'pump' or 'data'"); + } + else + { + // The LLSD object we got from our stream contains the keys we + // need. + LLEventPumps::instance().obtain(data["pump"]).post(data["data"]); + // Block calls to this method; resetting mBlocker unblocks calls + // to the other method. + mBlocker.reset(new LLEventPump::Blocker(mStdoutDataConnection)); + // Go check for any more pending events in the buffer. + if (childout.size()) + { + LLSD updata(data); + data["len"] = LLSD::Integer(childout.size()); + rstdout(updata); + } + } + } + return false; + } + + void bad_protocol(const std::string& data) + { + LL_WARNS("LLLeap") << mDesc << ": invalid protocol: " << data << LL_ENDL; + // No point in continuing to run this child. + mChild->kill(); + } + + // Listen on child stderr and log everything that arrives + bool rstderr(const LLSD& data) + { + LLProcess::ReadPipe& childerr(mChild->getReadPipe(LLProcess::STDERR)); + // We might have gotten a notification involving only a partial line + // -- or multiple lines. Read all complete lines; stop when there's + // only a partial line left. + while (childerr.contains('\n')) + { + // DO NOT make calls with side effects in a logging statement! If + // that log level is suppressed, your side effects WON'T HAPPEN. + std::string line(childerr.getline()); + // Log the received line. Prefix it with the desc so we know which + // plugin it's from. This method name rstderr() is intentionally + // chosen to further qualify the log output. + LL_INFOS("LLLeap") << mDesc << ": " << line << LL_ENDL; + } + // What if child writes a final partial line to stderr? + if (data["eof"].asBoolean() && childerr.size()) + { + std::string rest(childerr.read(childerr.size())); + // Read all remaining bytes and log. + LL_INFOS("LLLeap") << mDesc << ": " << rest << LL_ENDL; + } + return false; + } + + void fatalFunction(const std::string& error) + { + // Notify plugin + LLSD event; + event["type"] = "error"; + event["error"] = error; + mReplyPump.post(event); + + // All the above really accomplished was to buffer the serialized + // event in our WritePipe. Have to pump mainloop a couple times to + // really write it out there... but time out in case we can't write. + LLProcess::WritePipe& childin(mChild->getWritePipe(LLProcess::STDIN)); + LLEventPump& mainloop(LLEventPumps::instance().obtain("mainloop")); + LLSD nop; + F64 until(LLTimer::getElapsedSeconds() + 2); + while (childin.size() && LLTimer::getElapsedSeconds() < until) + { + mainloop.post(nop); + } + + // forward the call to the previous FatalFunction + mPrevFatalFunction(error); + } + +private: + /// We always want to listen on mReplyPump with wstdin(); under some + /// circumstances we'll also echo other LLEventPumps to the plugin. + LLBoundListener connect(LLEventPump& pump, const std::string& listener) + { + // Serialize any event received on the specified LLEventPump to our + // child's stdin, suitably enriched with the pump name on which it was + // received. + return pump.listen(listener, + boost::bind(&LLLeapImpl::wstdin, this, pump.getName(), _1)); + } + + std::string mDesc; + LLEventStream mDonePump; + LLEventStream mReplyPump; + LLProcessPtr mChild; + LLTempBoundListener + mStdinConnection, mStdoutConnection, mStdoutDataConnection, mStderrConnection; + boost::scoped_ptr<LLEventPump::Blocker> mBlocker; + LLProcess::ReadPipe::size_type mExpect; + LLError::FatalFunction mPrevFatalFunction; + boost::scoped_ptr<LLLeapListener> mListener; +}; + +// This must follow the declaration of LLLeapImpl, so it may as well be last. +LLLeap* LLLeap::create(const std::string& desc, const std::vector<std::string>& plugin, bool exc) +{ + // If caller is willing to permit exceptions, just instantiate. + if (exc) + return new LLLeapImpl(desc, plugin); + + // Caller insists on suppressing LLLeap::Error. Very well, catch it. + try + { + return new LLLeapImpl(desc, plugin); + } + catch (const LLLeap::Error&) + { + return NULL; + } +} + +LLLeap* LLLeap::create(const std::string& desc, const std::string& plugin, bool exc) +{ + // Use LLStringUtil::getTokens() to parse the command line + return create(desc, + LLStringUtil::getTokens(plugin, + " \t\r\n", // drop_delims + "", // no keep_delims + "\"'", // either kind of quotes + "\\"), // backslash escape + exc); +} |