Move files to prepare for assimilation into core

[libs/core.git] / source / io / pipe.cpp

diff --git a/source/io/pipe.cpp b/source/io/pipe.cpp
new file mode 100644 (file)
index 0000000..b3735aa
--- /dev/null
+++ b/source/io/pipe.cpp
@@ -0,0 +1,182 @@
+#ifndef WIN32
+#include <fcntl.h>
+#include <errno.h>
+#endif
+#include <msp/strings/formatter.h>
+#include "pipe.h"
+
+using namespace std;
+
+namespace Msp {
+namespace IO {
+
+Pipe::Pipe()
+{
+#ifdef WIN32
+       string name = format("\\\\.\\pipe\\%u.%p", GetCurrentProcessId(), this);
+       handle[0] = CreateNamedPipe(name.c_str(), PIPE_ACCESS_INBOUND|FILE_FLAG_OVERLAPPED, PIPE_TYPE_BYTE, 1, 1024, 1024, 0, 0);
+       if(handle[0]==INVALID_HANDLE_VALUE)
+               throw SystemError("Unable to create pipe", GetLastError());
+
+       handle[1] = CreateFile(name.c_str(), GENERIC_WRITE, 0, 0, OPEN_EXISTING, 0, 0);
+       if(handle[1]==INVALID_HANDLE_VALUE)
+       {
+               unsigned err = GetLastError();
+               CloseHandle(handle[0]);
+               throw SystemError("Unable to create pipe", err);
+       }
+
+       overlapped = 0;
+       event = CreateEvent(0, true, false, 0);
+       buf_size = 1024;
+       buffer = new char[buf_size];
+       buf_avail = 0;
+       buf_next = buffer;
+#else
+       if(pipe(handle)==-1)
+               throw SystemError("Unable to create pipe", errno);
+#endif
+
+       set_events(P_INPUT);
+}
+
+Pipe::~Pipe()
+{
+       close();
+}
+
+void Pipe::close()
+{
+       set_events(P_NONE);
+
+       signal_flush_required.emit();
+#ifdef WIN32
+       CloseHandle(handle[0]);
+       CloseHandle(handle[1]);
+#else
+       ::close(handle[0]);
+       ::close(handle[1]);
+       signal_closed.emit();
+#endif
+}
+
+void Pipe::set_block(bool b)
+{
+       mode = (mode&~M_NONBLOCK);
+       if(b)
+               mode = (mode|M_NONBLOCK);
+
+#ifndef WIN32
+       int flags = fcntl(handle[0], F_GETFD);
+       fcntl(handle[0], F_SETFL, (flags&O_NONBLOCK)|(b?0:O_NONBLOCK));
+       flags = fcntl(handle[1], F_GETFD);
+       fcntl(handle[1], F_SETFL, (flags&O_NONBLOCK)|(b?0:O_NONBLOCK));
+#endif
+}
+
+unsigned Pipe::do_write(const char *buf, unsigned size)
+{
+       if(size==0)
+               return 0;
+
+#ifdef WIN32
+       DWORD ret;
+       if(!WriteFile(handle[1], buf, size, &ret, 0))
+               throw SystemError("Writing to pipe failed", GetLastError());
+#else
+       int ret = ::write(handle[1], buf, size);
+       if(ret==-1)
+       {
+               if(errno==EAGAIN)
+                       return 0;
+               else
+                       throw SystemError("Writing to pipe failed", errno);
+       }
+#endif
+
+       return ret;
+}
+
+unsigned Pipe::do_read(char *buf, unsigned size)
+{
+       if(size==0)
+               return 0;
+
+#ifdef WIN32
+       // Initiate overlapped read if needed
+       get_event_handle();
+
+       if(overlapped)
+       {
+               DWORD ret;
+               if(!GetOverlappedResult(handle[0], overlapped, &ret, !buf_avail))
+                       throw SystemError("Reading from pipe failed", GetLastError());
+               else
+               {
+                       buf_avail += ret;
+                       delete overlapped;
+                       overlapped = 0;
+               }
+       }
+
+       unsigned ret = min(buf_avail, size);
+       memcpy(buf, buf_next, ret);
+       buf_next += ret;
+       buf_avail -= ret;
+
+       // Initiate another overlapped read in case someone is polling us
+       get_event_handle();
+#else
+       int ret = ::read(handle[0], buf, size);
+       if(ret==-1)
+       {
+               if(errno==EAGAIN)
+                       return 0;
+               else
+                       throw SystemError("Reading from pipe failed", errno);
+       }
+#endif
+
+       if(ret==0)
+       {
+               eof_flag = true;
+               signal_end_of_file.emit();
+       }
+
+       return ret;
+}
+
+Handle Pipe::get_event_handle()
+{
+#ifdef WIN32
+       if(!overlapped && !buf_avail)
+       {
+               overlapped = new OVERLAPPED;
+               memset(overlapped, 0, sizeof(OVERLAPPED));
+               overlapped->hEvent = event;
+
+               DWORD ret;
+               buf_next = buffer;
+               if(!ReadFile(handle[0], buffer, buf_size, &ret, overlapped))
+               {
+                       unsigned err = GetLastError();
+                       if(err!=ERROR_IO_PENDING)
+                               throw SystemError("Failed to start an overlapped read", err);
+               }
+               else
+               {
+                       buf_avail = ret;
+                       delete overlapped;
+                       overlapped = 0;
+                       SetEvent(event);
+               }
+       }
+
+       return event;
+#else
+       return handle[0];
+#endif
+}
+
+} // namespace IO
+} // namespace Msp