com32/lib/sys/file.h

   1 /* ----------------------------------------------------------------------- *
   2  *
   3  *   Copyright 2003-2004 H. Peter Anvin - All Rights Reserved
   4  *
   5  *   Permission is hereby granted, free of charge, to any person
   6  *   obtaining a copy of this software and associated documentation
   7  *   files (the "Software"), to deal in the Software without
   8  *   restriction, including without limitation the rights to use,
   9  *   copy, modify, merge, publish, distribute, sublicense, and/or
  10  *   sell copies of the Software, and to permit persons to whom
  11  *   the Software is furnished to do so, subject to the following
  12  *   conditions:
  13  *
  14  *   The above copyright notice and this permission notice shall
  15  *   be included in all copies or substantial portions of the Software.
  16  *
  17  *   THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  18  *   EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
  19  *   OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  20  *   NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
  21  *   HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
  22  *   WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  23  *   FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  24  *   OTHER DEALINGS IN THE SOFTWARE.
  25  *
  26  * ----------------------------------------------------------------------- */
  27
  28 /*
  29  * file.h
  30  *
  31  * Internal implementation of file I/O for COM32
  32  */
  33
  34 #ifndef _COM32_SYS_FILE_H
  35 #define _COM32_SYS_FILE_H
  36
  37 #include <inttypes.h>
  38 #include <stdlib.h>
  39 #include <sys/types.h>
  40 #include <dev.h>
  41 #include <fcntl.h>
  42
  43 /* Device structure; contains the relevant operations */
  44
  45 struct file_info;
  46
  47 #define __DEV_MAGIC     0xf4e7
  48 #define __DEV_TTY       0x0001  /* TTY - must be bit 0 */
  49 #define __DEV_FILE      0x0002  /* Ordinary file */
  50 #define __DEV_OUTPUT    0x0004  /* This is an output device */
  51 #define __DEV_INPUT     0       /* Dummy */
  52 #define __DEV_ERROR     0x0008  /* This is the error device */
  53 #define __DEV_NULL      0x0010  /* This is the null device */
  54
  55 struct input_dev {
  56   uint16_t dev_magic;           /* Magic number */
  57   uint16_t flags;               /* Flags */
  58   int fileflags;                /* Permitted file flags */
  59   ssize_t (*read)(struct file_info *, void *, size_t);
  60   int (*close)(struct file_info *);
  61   int (*open)(struct file_info *);
  62 };
  63
  64 struct output_dev {
  65   uint16_t dev_magic;           /* Magic number */
  66   uint16_t flags;               /* Flags */
  67   int fileflags;
  68   ssize_t (*write)(struct file_info *, const void *, size_t);
  69   int (*close)(struct file_info *);
  70   int (*open)(struct file_info *);
  71   const struct output_dev *fallback; /* Fallback option for certain consoles */
  72 };
  73
  74 /* File structure */
  75
  76 #define NFILES 32               /* Number of files to support */
  77 #define MAXBLOCK 16384          /* Defined by ABI */
  78
  79 struct file_info {
  80   const struct input_dev *iop;  /* Input operations */
  81   const struct output_dev *oop; /* Output operations */
  82
  83   /* Structure used for input blocking */
  84   struct {
  85     int blocklg2;               /* Blocksize log 2 */
  86     size_t offset;              /* Current file offset */
  87     size_t length;              /* Total file length */
  88     uint16_t filedes;           /* File descriptor */
  89     uint16_t _filler;           /* Unused */
  90     size_t nbytes;              /* Number of bytes available in buffer */
  91     char *datap;                /* Current data pointer */
  92     char buf[MAXBLOCK];
  93   } i;
  94
  95   /* Output file data */
  96   struct {
  97     int rows, cols;             /* Rows and columns */
  98   } o;
  99 };
 100
 101 extern struct file_info __file_info[NFILES];
 102
 103 /* Line input discipline */
 104 ssize_t __line_input(struct file_info *fp, char *buf, size_t bufsize,
 105                      ssize_t (*get_char)(struct file_info *, void *, size_t));
 106
 107 #endif /* _COM32_SYS_FILE_H */