io.h

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/*
 * I/O and buffering
 */

#ifndef __io_h__
#define __io_h__

#include "headers.h"
#include "types.h"

/** I/O */
struct _io {
        /** Input path, if given on the command line.  This is used when copying a
         * file into a directory, the base filename of the input file is used as the
         * filename in the destination directory, so we need to keep it around. */
        char *in_path;
        /** Input file descriptor. */
        int in;
        /** Output file descriptor. */
        int out;
        /** Flag: Input source is ready to be read. */
        int in_ready;
        /** Flag: Output source is ready to be written to. */
        int out_ready;
        /** Flag: End of input has been reached. */
        int eof_in;
        /** Flag: End of output has been reached. */
        int eof_out;
        /** The size of the I/O buffer. */
        size_t buffer_size;
        /** A pointer to the I/O buffer. */
        char *buffer;
        /** The location of the start of the ring buffer. */
        size_t buffer_head;
        /** The length of the ring buffer. */
        size_t buffer_used;
        /** The number of bytes read the last time I/O was performed. */
        ssize_t last_read;
        /** The number of bytes written the last time I/O was performed. */
        ssize_t last_write;
        /** The total number of bytes read. */
        uint64 total_read;
        /** The total number of bytes written. */
        uint64 total_write;
        /** The total size of the input stream, if known. */
        uint64 total_size;
        /** If continuing from a previously interrupted stream, assume that this
         * many bytes have already been read and written. */
        uint64 continue_size;
        /** Flag: Whether or not the total size of the input stream is known. */
        int total_size_known;
        /** The number of microseconds to wait for a change in I/O state. */
        uint32 timeout;
        /** The current time, used for throttling input. */
        time_t current_time;
        /** The maximum number of bytes per second that we're allowed to read. */
        uint64 throttle;
        /** The number if bytes read so far for this second. */
        uint64 throttle_count;
        /** The size of a block in bytes, used for calculating total_size and
         * buffer_size. */
        uint64 block_size;
        };

typedef struct _io IO;

extern IO io;

int ioInit(void);
int ioBegin(void);
int ioEnd(void);
void ioCheck(void);
int ioRead(void);
int ioWrite(void);
int ioIsDone(void);

#endif

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