xref: /original-bsd/usr.bin/make/buf.h (revision e59fb703)
1 /*
2  * Copyright (c) 1988, 1989, 1990 The Regents of the University of California.
3  * Copyright (c) 1988, 1989 by Adam de Boor
4  * Copyright (c) 1989 by Berkeley Softworks
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to Berkeley by
8  * Adam de Boor.
9  *
10  * %sccs.include.redist.c%
11  *
12  *	@(#)buf.h	5.4 (Berkeley) 12/28/90
13  */
14 
15 /*-
16  * buf.h --
17  *	Header for users of the buf library.
18  */
19 
20 #ifndef _BUF_H
21 #define _BUF_H
22 
23 #include    "sprite.h"
24 
25 typedef unsigned char Byte;
26 
27 typedef struct Buffer {
28     int	    size; 	/* Current size of the buffer */
29     int     left;	/* Space left (== size - (inPtr - buffer)) */
30     Byte    *buffer;	/* The buffer itself */
31     Byte    *inPtr;	/* Place to write to */
32     Byte    *outPtr;	/* Place to read from */
33 } *Buffer;
34 
35 Buffer	    	  Buf_Init();	    /* Initialize a buffer */
36 void	    	  Buf_Destroy();    /* Destroy a buffer */
37 void	    	  Buf_AddBytes();   /* Add a range of bytes to a buffer */
38 int	    	  Buf_GetByte();    /* Get a byte from a buffer */
39 int	    	  Buf_GetBytes();   /* Get multiple bytes */
40 void		  Buf_UngetByte();  /* Push a byte back into the buffer */
41 void		  Buf_UngetBytes(); /* Push many bytes back into the buf */
42 Byte	    	  *Buf_GetAll();    /* Get them all */
43 void	    	  Buf_Discard();    /* Throw away some of the bytes */
44 int	    	  Buf_Size();	    /* See how many are there */
45 
46 /* Buf_AddByte adds a single byte to a buffer. */
47 #define	Buf_AddByte(bp, byte) \
48 	(--(bp)->left <= 0 ? Buf_OvAddByte(bp, byte) : \
49 		(void)(*(bp)->inPtr++ = (byte), *(bp)->inPtr = 0))
50 
51 void	Buf_OvAddByte();		/* adds a byte when buffer overflows */
52 
53 #define BUF_ERROR 256
54 
55 #endif _BUF_H
56