Chris@2: /* -*- c-basic-offset: 4 indent-tabs-mode: nil -*-  vi:set ts=8 sts=4 sw=4: */
Chris@5: /*
Chris@5:     Copyright (c) 2016 Queen Mary, University of London
Chris@5: 
Chris@5:     Permission is hereby granted, free of charge, to any person
Chris@5:     obtaining a copy of this software and associated documentation
Chris@5:     files (the "Software"), to deal in the Software without
Chris@5:     restriction, including without limitation the rights to use, copy,
Chris@5:     modify, merge, publish, distribute, sublicense, and/or sell copies
Chris@5:     of the Software, and to permit persons to whom the Software is
Chris@5:     furnished to do so, subject to the following conditions:
Chris@5: 
Chris@5:     The above copyright notice and this permission notice shall be
Chris@5:     included in all copies or substantial portions of the Software.
Chris@5: 
Chris@5:     THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
Chris@5:     EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
Chris@5:     MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
Chris@5:     NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
Chris@5:     CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
Chris@5:     CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
Chris@5:     WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
Chris@5: 
Chris@5:     Except as contained in this notice, the names of the Centre for
Chris@5:     Digital Music and Queen Mary, University of London shall not be
Chris@5:     used in advertising or otherwise to promote the sale, use or other
Chris@5:     dealings in this Software without prior written authorization.
Chris@5: */
Chris@2: 
Chris@2: #include "plugincandidates.h"
Chris@2: 
Chris@2: #include <set>
Chris@2: #include <stdexcept>
Chris@2: #include <iostream>
Chris@2: 
Chris@2: #include <QProcess>
Chris@2: #include <QDir>
Chris@6: #include <QTime>
Chris@2: 
Chris@4: #if defined(_WIN32)
Chris@2: #define PLUGIN_GLOB "*.dll"
Chris@4: #elif defined(__APPLE__)
Chris@2: #define PLUGIN_GLOB "*.dylib *.so"
Chris@2: #else
Chris@2: #define PLUGIN_GLOB "*.so"
Chris@2: #endif
Chris@2: 
Chris@2: using namespace std;
Chris@2: 
Chris@2: PluginCandidates::PluginCandidates(string helperExecutableName) :
Chris@6:     m_helper(helperExecutableName),
Chris@6:     m_logCallback(0)
Chris@2: {
Chris@2: }
Chris@2: 
Chris@6: void
Chris@6: PluginCandidates::setLogCallback(LogCallback *cb)
Chris@6: {
Chris@6:     m_logCallback = cb;
Chris@6: }
Chris@6: 
Chris@2: vector<string>
Chris@4: PluginCandidates::getCandidateLibrariesFor(string tag) const
Chris@2: {
Chris@4:     if (m_candidates.find(tag) == m_candidates.end()) return {};
Chris@4:     else return m_candidates.at(tag);
Chris@2: }
Chris@2: 
Chris@2: vector<PluginCandidates::FailureRec>
Chris@4: PluginCandidates::getFailedLibrariesFor(string tag) const
Chris@2: {
Chris@4:     if (m_failures.find(tag) == m_failures.end()) return {};
Chris@4:     else return m_failures.at(tag);
Chris@2: }
Chris@2: 
Chris@6: void
Chris@6: PluginCandidates::log(string message)
Chris@6: {
Chris@6:     if (m_logCallback) m_logCallback->log("PluginCandidates: " + message);
Chris@6: }
Chris@6: 
Chris@2: vector<string>
Chris@2: PluginCandidates::getLibrariesInPath(vector<string> path)
Chris@2: {
Chris@2:     vector<string> candidates;
Chris@2: 
Chris@2:     for (string dirname: path) {
Chris@2: 
Chris@6:         log("scanning directory " + dirname + "\n");
Chris@2: 
Chris@2:         QDir dir(dirname.c_str(), PLUGIN_GLOB,
Chris@2: 		 QDir::Name | QDir::IgnoreCase,
Chris@2: 		 QDir::Files | QDir::Readable);
Chris@2: 
Chris@2: 	for (unsigned int i = 0; i < dir.count(); ++i) {
Chris@2:             QString soname = dir.filePath(dir[i]);
Chris@2:             candidates.push_back(soname.toStdString());
Chris@2:         }
Chris@2:     }
Chris@2: 
Chris@2:     return candidates;
Chris@2: }
Chris@2: 
Chris@2: void
Chris@2: PluginCandidates::scan(string tag,
Chris@2: 		       vector<string> pluginPath,
Chris@4: 		       string descriptorSymbolName)
Chris@2: {
Chris@2:     vector<string> libraries = getLibrariesInPath(pluginPath);
Chris@2:     vector<string> remaining = libraries;
Chris@2: 
Chris@2:     int runlimit = 20;
Chris@2:     int runcount = 0;
Chris@2:     
Chris@2:     vector<string> result;
Chris@2:     
Chris@2:     while (result.size() < libraries.size() && runcount < runlimit) {
Chris@4: 	vector<string> output = runHelper(remaining, descriptorSymbolName);
Chris@2: 	result.insert(result.end(), output.begin(), output.end());
Chris@2: 	int shortfall = int(remaining.size()) - int(output.size());
Chris@2: 	if (shortfall > 0) {
Chris@2: 	    // Helper bailed out for some reason presumably associated
Chris@2: 	    // with the plugin following the last one it reported
Chris@4: 	    // on. Add a failure entry for that one and continue with
Chris@4: 	    // the following ones.
Chris@6:             string failed = *(remaining.rbegin() + shortfall - 1);
Chris@6:             log("helper output ended before result for plugin " + failed + "\n");
Chris@6: 	    result.push_back("FAILURE|" + failed + "|Plugin load check failed or timed out");
Chris@4:             remaining = vector<string>
Chris@4:                 (remaining.rbegin(), remaining.rbegin() + shortfall - 1);
Chris@2: 	}
Chris@2: 	++runcount;
Chris@2:     }
Chris@2: 
Chris@2:     recordResult(tag, result);
Chris@2: }
Chris@2: 
Chris@2: vector<string>
Chris@2: PluginCandidates::runHelper(vector<string> libraries, string descriptor)
Chris@2: {
Chris@2:     vector<string> output;
Chris@6: 
Chris@6:     log("running helper with following library list:\n");
Chris@6:     for (auto &lib: libraries) log(lib + "\n");
Chris@2: 
Chris@2:     QProcess process;
Chris@2:     process.setReadChannel(QProcess::StandardOutput);
Chris@4:     process.setProcessChannelMode(QProcess::ForwardedErrorChannel);
Chris@2:     process.start(m_helper.c_str(), { descriptor.c_str() });
Chris@2:     if (!process.waitForStarted()) {
Chris@2: 	cerr << "helper failed to start" << endl;
Chris@2: 	throw runtime_error("plugin load helper failed to start");
Chris@2:     }
Chris@2:     for (auto &lib: libraries) {
Chris@2: 	process.write(lib.c_str(), lib.size());
Chris@2: 	process.write("\n", 1);
Chris@2:     }
Chris@2: 
Chris@6:     QTime t;
Chris@6:     t.start();
Chris@6:     int timeout = 3000; // ms
Chris@6: 
Chris@2:     int buflen = 4096;
Chris@4:     bool done = false;
Chris@4:     
Chris@4:     while (!done) {
Chris@2: 	char buf[buflen];
Chris@2: 	qint64 linelen = process.readLine(buf, buflen);
Chris@4:         if (linelen > 0) {
Chris@4:             output.push_back(buf);
Chris@4:             done = (output.size() == libraries.size());
Chris@4:         } else if (linelen < 0) {
Chris@4:             // error case
Chris@6:             log("received error code while reading from helper\n");
Chris@4:             done = true;
Chris@4: 	} else {
Chris@4:             // no error, but no line read (could just be between
Chris@4:             // lines, or could be eof)
Chris@4:             done = (process.state() == QProcess::NotRunning);
Chris@6:             if (!done) {
Chris@6:                 if (t.elapsed() > timeout) {
Chris@6:                     // this is purely an emergency measure
Chris@6:                     log("timeout: helper took too long, killing it\n");
Chris@6:                     process.kill();
Chris@6:                     done = true;
Chris@6:                 } else {
Chris@6:                     process.waitForReadyRead(200);
Chris@6:                 }
Chris@6:             }
Chris@2:         }
Chris@4:     }
Chris@4: 
Chris@4:     if (process.state() != QProcess::NotRunning) {
Chris@4:         process.close();
Chris@4:         process.waitForFinished();
Chris@4:     }
Chris@2: 	
Chris@2:     return output;
Chris@2: }
Chris@2: 
Chris@2: void
Chris@2: PluginCandidates::recordResult(string tag, vector<string> result)
Chris@2: {
Chris@4:     for (auto &r: result) {
Chris@4: 
Chris@4:         QString s(r.c_str());
Chris@4:         QStringList bits = s.split("|");
Chris@6: 
Chris@6:         log("read output line from helper: " + r);
Chris@6:         
Chris@4:         if (bits.size() < 2 || bits.size() > 3) {
Chris@6:             log("invalid output line (wrong number of |-separated fields)\n");
Chris@4:             continue;
Chris@4:         }
Chris@4: 
Chris@4:         string status = bits[0].toStdString();
Chris@4:         
Chris@4:         string library = bits[1].toStdString();
Chris@4:         if (bits.size() == 2) library = bits[1].trimmed().toStdString();
Chris@4: 
Chris@4:         string message = "";
Chris@4:         if (bits.size() > 2) message = bits[2].trimmed().toStdString();
Chris@4:         
Chris@4:         if (status == "SUCCESS") {
Chris@4:             m_candidates[tag].push_back(library);
Chris@4: 
Chris@4:         } else if (status == "FAILURE") {
Chris@4:             m_failures[tag].push_back({ library, message });
Chris@4: 
Chris@4:         } else {
Chris@6:             log("unexpected status \"" + status + "\" in output line\n");
Chris@4:         }
Chris@4:     }
Chris@2: }
Chris@2: