// ***************************************************************** -*- C++ -*-
// mt-test.cpp
// Sample multi-threading program
// Discussion: http://dev.exiv2.org/issues/1207
// Caution: This code isn't currently exercised by any bash script in the test suite
// This code is here for use in development when multi-threading issues
// are being discussed. For example #1207 and #1187
// It may be brought into use when Exiv2 support C++11 (#1188)
//
// WARNING: Only builds with clang and gcc < 4.9. I've never tried to build with Visual Studio
// requires C++11
// On Mac #define __cplusplus 201103L
// Older compilers #define __cplusplus 199711
// Compiler switches: -std=c++11 (set in samples/Makefile)
// WARNING: auto_ptr is not supported in C++11 implemented by gcc 4.9/C++11 and later
#include <exiv2/exiv2.hpp>
#include <iostream>
#include <iomanip>
#include <cassert>
#include <string>
#include <thread>
#include <mutex>
// mutex to for exclusive reporting
std::mutex m;
void reportExifMetadataCount(int n,const char* argv[])
{
int count = 0 ;
std::string what;
// count the exif metadata in the file
try {
Exiv2::Image::AutoPtr image = Exiv2::ImageFactory::open(argv[n]);
assert(image.get() != 0);
image->readMetadata();
Exiv2::ExifData &exifData = image->exifData();
if (!exifData.empty()) {
Exiv2::ExifData::const_iterator end = exifData.end();
for (Exiv2::ExifData::const_iterator i = exifData.begin(); i != end; ++i)
count++;
}
} catch (Exiv2::Error& e) {
what = e.what() ;
count = -1;
}
// report to the user
m.lock();
std::cout << "file: " << argv[n] << " "
<< "n: " << n << " "
<< "count: " << count << " "
<< (count < 0 ? "exception: " : what)
<< what << std::endl;
m.unlock();
}
int main(int argc,const char* argv[])
{
int result = 0;
if ( argc < 2 ) {
std::cerr << "syntax: " << argv[0] << " [path]+" << std::endl;
result = 1 ;
} else {
// Initialize XmpParser before starting threads
Exiv2::XmpParser::initialize();
// bucket of threads
std::thread* threads = new std::thread[argc+1];
// spin up the treads
for ( int arg = 1 ; arg < argc ; arg++ ) {
threads[arg] = std::thread(reportExifMetadataCount,arg,argv);
}
// wait for them to finish
for ( int arg = 1 ; arg < argc ; arg++ ) {
if ( threads[arg].joinable() )
threads[arg].join();
}
delete [] threads;
}
return result;
}
// That's all Folks!
////