//----------------------------------------------------------------------------//
//                           GNU GPL OS/K                                     //
//                                                                            //
//  Desc:       Buffer library                                                //
//                                                                            //
//                                                                            //
//  Copyright © 2018-2019 The OS/K Team                                       //
//                                                                            //
//  This file is part of OS/K.                                                //
//                                                                            //
//  OS/K 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         //
//  any later version.                                                        //
//                                                                            //
//  OS/K 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 OS/K.  If not, see <https://www.gnu.org/licenses/>.            //
//----------------------------------------------------------------------------//

#ifndef _KALKERN_BASE_H
#include <kernel/base.h>
#endif

#ifndef _KALKERN_BUF_H
#define _KALKERN_BUF_H

typedef struct Buffer_t     Buffer_t;

//
// Buffer flags
//
enum
{
    BF_LINE = 1,        // Line-buffered
    BF_FILE = 2,        // Linked to a file
    BF_ALLOC = 4,       // Buffer was malloc'd
    BF_FONCLOSE = 8,    // Don't flush on close
};

//
// Buffer states
//
enum
{
    BS_CLOSED = 0,      // Buffer closed (need allocation)
    BS_EOF,             // Buffer closed, or end of file reached
    BS_ERR,             // Buffer not ready, an error happened

    // Buffer ready for...
    BS_RDWR,            // Both reading and writing
    BS_RDONLY,          // Only for reading
    BS_WRONLY,          // Only for writing
};

typedef error_t (*BFlusher_t)(Buffer_t *);

struct Buffer_t
{
    uint        initDone;
    Lock_t      lock;

    int         flags;      // Buffer flags
    int         state;      // Buffer state

    size_t      size;       // Current size

    char       *buf;        // Beginning of buffer
    char       *rp;         // Read pointer
    char       *wp;         // Write pointer

    BFlusher_t  flusher;    // Called for flushing

    // The following parameters are only used in line buf mode

    int         lastLF;     // Characters since beginning of line
    int         lineLen;    // Line length (for line buffers)
    int         nLines;     // Number of lines in "true" buffer
                            // size/(lineLen*nLines) - 1 playback buffers
};

extern Buffer_t BStdOut, BStdErr;

error_t     BCloseBuf(Buffer_t *buf);
void        BFlushOnClose(Buffer_t *buf);

Buffer_t   *BOpenPureBuf(char *source, size_t size);

// Creates a lined buffer of pbCount*nLines lines each
// of lineLen length (pb = playback buffer, for scrolling up)
// If source==NULL, malloc the buffer
Buffer_t   *BOpenLineBuf(char *source, int mode, int lineLen,
                         int nLines, int pbCount, BFlusher_t flusher);

int         BGetFlags(Buffer_t *buf);
int         BGetState(Buffer_t *buf);
int         BGetLineLen(Buffer_t *buf);
void        BSetLineLen(Buffer_t *buf, int len);

void        BLockBuf(Buffer_t *buf);
void        BUnlockBuf(Buffer_t *buf);
bool        BTrylockBuf(Buffer_t *buf);

error_t     BFlushBuf(Buffer_t *buf);
error_t     BPutOnBuf(Buffer_t *buf, uchar ch);
error_t     BPrintOnBuf(Buffer_t *buf, size_t n, const char *fmt, ...);
error_t     BPrintOnBufV(Buffer_t *buf, size_t n, const char *fmt, va_list ap);

#endif