openfoam/applications/test/OFstream/Test-OFstream.cxx
Mark Olesen ee895577ae ENH: improve OFstream append behaviour (#3160)
- previous support for file appending (largely unused) always
  specified opening with the std::ios_base::app flag.

  Now differentiate between append behaviours:

  APPEND_APP
  ~~~~~~~~~~
  Corresponds to std::ios_base::app behaviour:

  - Existing files will be preserved and a seek-to-end is performed at
    every write. With this mode seeks/repositioning within the file
    will effectively be ignored on output.

  APPEND_ATE
  ~~~~~~~~~~
  Largely approximates std::ios_base::ate behaviour:

  - Existing files will be preserved and a seek-to-end is performed
    immediately after opening, but not subsequently. Can use seekp()
    to overwrite parts of a file.
2024-05-29 14:04:52 +00:00

337 lines
7.7 KiB
C++

/*---------------------------------------------------------------------------*\
========= |
\\ / F ield | OpenFOAM: The Open Source CFD Toolbox
\\ / O peration |
\\ / A nd | www.openfoam.com
\\/ M anipulation |
-------------------------------------------------------------------------------
Copyright (C) 2022-2024 OpenCFD Ltd.
-------------------------------------------------------------------------------
License
This file is part of OpenFOAM.
OpenFOAM is free software: you can redistribute it and/or modify it
under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
OpenFOAM is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
for more details.
You should have received a copy of the GNU General Public License
along with OpenFOAM. If not, see <http://www.gnu.org/licenses/>.
Description
Test OFstream. Primarily atomic operations
\*---------------------------------------------------------------------------*/
#include "Fstream.H"
#include "IOstreams.H"
#include "OSspecific.H"
#include "argList.H"
#include "clock.H"
#include "Switch.H"
#include "ListOps.H"
using namespace Foam;
std::string time_stamp;
void listFiles(const fileName& dir)
{
wordList files = ListOps::create<word>
(
readDir(dir, fileName::FILE),
nameOp<fileName>()
);
Info
<< nl
<< "files:" << nl
<< files << nl
<< "ls" << nl
<< "============" << endl;
Foam::system("ls -al " + dir);
Info<< "============" << endl;
}
OSstream& printInfo(OFstream& os)
{
InfoErr
<< "open: " << os.name() << nl
<< "appending: " << Switch::name(os.is_appending())
<< " tellp: "<< os.stdStream().tellp()
<< " gz: " << Switch::name(os.compression()) << nl;
return InfoErr.stream();
}
void withHeader(OFstream& os)
{
const auto tellp = os.stdStream().tellp();
if (tellp <= 0)
{
InfoErr
<< "Add header" << nl;
os << "HEADER: " << time_stamp.c_str() << nl;
}
}
template<class OSstreamType>
void generateLines(OSstreamType& os, label count = 1)
{
for (label line = 1; line <= count; ++line)
{
os << "[" << line
<< "] =============================================" << nl;
}
}
template<class OSstreamType>
void generateContent
(
OSstreamType& os,
const bool with_seekend,
const bool test_overwrite = false,
const int64_t seek_out = -1
)
{
if (with_seekend)
{
os.stdStream().seekp(0, std::ios_base::end);
// OR? os.seek_end();
}
printInfo(os);
withHeader(os);
if (test_overwrite && seek_out >= 0)
{
InfoErr<< "... seekp(" << seek_out << ")" << nl;
auto& oss = os.stdStream();
// Actually std::streampos, but cannot increment that
int64_t pos(seek_out);
const int64_t tellp_end = oss.tellp();
if (pos >= 0 && pos < tellp_end)
{
InfoErr
<< "... fill from " << label(pos)
<< " to " << label(tellp_end) << nl;
oss.seekp(pos);
while (pos < tellp_end)
{
// Fill with char 'X', rely on streambuf buffering
oss << 'X';
++pos;
}
oss.seekp(seek_out);
os << "More content [at " << seek_out << ']' << endl;
}
}
generateLines(os, 4);
printInfo(os)
<< "... sleep" << endl;
listFiles(os.name().path());
sleep(2);
os << "[new content] +++++++++++++++++++++++++++++++++++" << endl;
}
template<class OSstreamType>
void generateOverwriteContent
(
OSstreamType& os,
const bool with_seekend,
const int64_t seek_out = -1
)
{
generateContent(os, with_seekend, true, seek_out);
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
// Main program:
int main(int argc, char *argv[])
{
argList::addBoolOption("gz", "Use compression");
argList::addBoolOption("append-app", "Use append app mode");
argList::addBoolOption("append-ate", "Use append ate mode");
argList::addBoolOption("seekend", "Seek to end after non-append open");
argList::addOption("seek", "value", "Seek from start (default: 100)");
argList::addBoolOption("atomic", "Use atomic");
argList::addBoolOption("keep", "Do not remove test directory");
argList::addOption("write", "file", "test writing to file");
#include "setRootCase.H"
// Same time-stamp for all generated files
time_stamp = clock::dateTime();
const fileName baseDir("Test-OFstream-directory");
Foam::mkDir(baseDir);
InfoErr<< "mkdir: " << baseDir << endl;
Info<< "start:" << nl;
listFiles(baseDir);
const bool with_seekend = args.found("seekend");
const int seek_out = args.getOrDefault<int>("seek", 100);
IOstreamOption streamOpt;
if (args.found("gz"))
{
streamOpt.compression(IOstreamOption::COMPRESSED);
}
IOstreamOption::appendType append =
(
args.found("append-app") ? IOstreamOption::APPEND_APP
: args.found("append-ate") ? IOstreamOption::APPEND_ATE
: IOstreamOption::NO_APPEND
);
IOstreamOption::atomicType atomic =
(
args.found("atomic")
? IOstreamOption::ATOMIC
: IOstreamOption::NON_ATOMIC
);
{
OFstream(baseDir/"dummy")() << "Some file content" << endl;
Foam::ln("dummy", baseDir/"Test3.txt");
Foam::ln("dummy", baseDir/"Test4.txt");
Foam::ln("dummy", baseDir/"Test4.txt.gz");
Foam::ln("dummy", baseDir/"Test5.txt");
Foam::ln("dummy", baseDir/"Test5.txt.gz");
}
{
OFstream os
(
atomic,
baseDir/"Test1.txt",
streamOpt,
append
);
generateOverwriteContent(os, with_seekend, seek_out);
}
{
OFstream os
(
atomic,
baseDir/"Test1-app.txt",
streamOpt,
IOstreamOption::APPEND_APP
);
generateOverwriteContent(os, with_seekend, seek_out);
}
{
OFstream os
(
atomic,
baseDir/"Test1-ate.txt",
streamOpt,
IOstreamOption::APPEND_ATE
);
generateOverwriteContent(os, with_seekend, seek_out);
}
{
OFstream os
(
atomic,
baseDir/"Test2.txt",
streamOpt
);
generateContent(os, with_seekend);
}
{
OFstream os
(
atomic,
baseDir/"Test3.txt",
streamOpt,
IOstreamOption::APPEND_APP
);
generateContent(os, with_seekend, with_seekend);
}
{
OFstream os
(
baseDir/"Test4.txt",
IOstreamOption::ASCII,
IOstreamOption::COMPRESSED
);
// No seekend with COMPRESSED
generateContent(os, false);
}
{
OFstream os
(
IOstreamOption::ATOMIC,
baseDir/"Test5.txt"
);
generateContent(os, with_seekend);
}
Info<< nl << "done:" << endl;
listFiles(baseDir);
if (args.found("keep"))
{
InfoErr<< "keep: " << baseDir << endl;
}
else
{
InfoErr<< "rmdir: " << baseDir << endl;
Foam::rmDir(baseDir);
}
Info<< "\nEnd\n" << endl;
return 0;
}
// ************************************************************************* //