#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include <io/pipe.h>
#include <sys/atomic.h>
#include <hwo/threads.h>

FILE* pipe(int size)
{
	fdPIPE* stream;
	stream = (fdPIPE*)fdev_create(sizeof(PIPE),(fdevput)pipe_put,(fdevget)pipe_get,NULL,NULL);
	if (!stream)
	{
		return NULL;
	};
			
	stream->pipe.size = size;
	stream->pipe.buffer = malloc(size);
	if (!stream->pipe.buffer)
	{
		free(stream);
		return NULL;
	};
	
	return (FILE*)stream;
};

int pipe_get(FILE* stream)
{
	ATOMIC
	int c;
	
	if (pipe_empty( stream ) )
	{
		if (fdPIPE(stream)->pipe.options & IO_BLOCK_RD)
		{
			fdPIPE(stream)->pipe.wait_get = current_thread();
			thread_sleep(current_thread());
			fdPIPE(stream)->pipe.wait_get = NULL;
		} else
			return -1;
	};
		
	c = fdPIPE(stream)->pipe.buffer[ fdPIPE(stream)->pipe.read++ ];
	
	if (fdPIPE(stream)->pipe.read == fdPIPE(stream)->pipe.size)
		fdPIPE(stream)->pipe.read = 0;

	if (fdPIPE(stream)->pipe.wait_put)
		thread_wake( fdPIPE(stream)->pipe.wait_put );

	return c;
};

int pipe_put(char c,FILE* stream)
{
	ATOMIC
	
	if (pipe_full( stream ) )
	{
		if (fdPIPE(stream)->pipe.options & IO_BLOCK_WR)
		{
			fdPIPE(stream)->pipe.wait_put = current_thread();
			thread_sleep(current_thread());
			fdPIPE(stream)->pipe.wait_put = NULL;
		} else
			return -1;
	};

	fdPIPE(stream)->pipe.buffer[ fdPIPE(stream)->pipe.write++ ] = c;
	if (fdPIPE(stream)->pipe.write == fdPIPE(stream)->pipe.size)
		fdPIPE(stream)->pipe.write = 0;

	if (fdPIPE(stream)->pipe.wait_get)
		thread_wake( fdPIPE(stream)->pipe.wait_get );

	return 0;
};