Now mingw-w64 C++ compiler defines __USE_MINGW_ANSI_STDIO to 1, we
have to follow it as well. We hope that mingw version of stdio
function behaves like Linux ones. We have not tested them thoroughly
yet. pthread for windows defines its own HAVE_STRUCT_TIMESPEC macro.
To avoid warning, we rename our version of it as
HAVE_A2_STRUCT_TIMESPEC.
IOFile provides the same interface of old BufferedFile. It provides
extension points as pure virtual functions. Those functions are
implemented by 2 concrete subclasses: BufferedFile and GZipFile.
MINGW does not have vasprintf(), so we use _vscprintf() and
vsnprintf(). We want to reuse buffer, so for non-MINGW we use
vsnprintf() with retrying doubling buffer size if output is truncated.
Saved sessions may very large, as in hundreds and even thousands of
megabyte when dealing with large queues.
Add support to save and reload sessions to gzipped files, when libz is
available.
The session serializer will output gzipped contents when the file ends
with .gz, while the input file reader (UriListParser) will accept
whatever is thrown at it.
Tatsuhiro Tsujikawa