Rev 4921 | Go to most recent revision | Details | Compare with Previous | Last modification | View Log | RSS feed
Rev | Author | Line No. | Line |
---|---|---|---|
4921 | Serge | 1 | /* read.c -- read bytes from a input device. |
2 | * |
||
3 | * Copyright (c) 1995 Cygnus Support |
||
4 | * |
||
5 | * The authors hereby grant permission to use, copy, modify, distribute, |
||
6 | * and license this software and its documentation for any purpose, provided |
||
7 | * that existing copyright notices are retained in all copies and that this |
||
8 | * notice is included verbatim in any distributions. No written agreement, |
||
9 | * license, or royalty fee is required for any of the authorized uses. |
||
10 | * Modifications to this software may be copyrighted by their authors |
||
11 | * and need not follow the licensing terms described here, provided that |
||
12 | * the new terms are clearly indicated on the first page of each file where |
||
13 | * they apply. |
||
14 | */ |
||
15 | #include |
||
6536 | serge | 16 | #include |
4921 | Serge | 17 | #include "io.h" |
18 | |||
19 | #undef erro |
||
20 | extern int errno; |
||
21 | |||
22 | ssize_t read(int fd, void *buf, size_t cnt) |
||
23 | { |
||
24 | _ssize_t ret; |
||
25 | |||
26 | _ssize_t read_len, total_len; |
||
27 | unsigned reduce_idx, finish_idx; |
||
28 | unsigned iomode_flags; |
||
29 | char *buffer = buf; |
||
30 | int rc; |
||
31 | int h; |
||
32 | unsigned amount_read; |
||
33 | int err; |
||
34 | |||
35 | __io_handle *ioh; |
||
36 | |||
37 | if( (fd < 0) || (fd >=64) ) |
||
38 | { |
||
39 | errno = EBADF; |
||
40 | return -1; |
||
41 | }; |
||
42 | |||
43 | ioh = &__io_tab[fd]; |
||
44 | |||
45 | iomode_flags = ioh->mode; |
||
46 | |||
47 | if( iomode_flags == 0 ) |
||
48 | { |
||
49 | errno = EBADF; |
||
50 | return( -1 ); |
||
51 | } |
||
52 | |||
53 | if( !(iomode_flags & _READ) ) |
||
54 | { |
||
55 | errno = EACCES; |
||
56 | return( -1 ); |
||
57 | } |
||
58 | |||
59 | if( iomode_flags & _BINARY ) /* if binary mode */ |
||
60 | { |
||
6536 | serge | 61 | err = ioh->read(ioh->name, buffer, ioh->offset, cnt, &amount_read); |
4921 | Serge | 62 | ioh->offset+= amount_read; |
63 | total_len = amount_read; |
||
64 | |||
65 | if(err) |
||
66 | if ( amount_read == 0) |
||
67 | return (-1); |
||
68 | } |
||
69 | else |
||
70 | { |
||
71 | total_len = 0; |
||
72 | read_len = cnt; |
||
73 | do |
||
74 | { |
||
6536 | serge | 75 | err=ioh->read(ioh->name,buffer, ioh->offset, cnt, &amount_read); |
4921 | Serge | 76 | ioh->offset+=amount_read; |
77 | |||
78 | if( amount_read == 0 ) |
||
79 | break; /* EOF */ |
||
80 | |||
81 | reduce_idx = 0; |
||
82 | finish_idx = reduce_idx; |
||
83 | for( ; reduce_idx < amount_read; ++reduce_idx ) |
||
84 | { |
||
85 | if( buffer[ reduce_idx ] == 0x1a ) /* EOF */ |
||
86 | { |
||
87 | lseek(fd, ((long)reduce_idx - (long)amount_read)+1L, SEEK_CUR ); |
||
88 | total_len += finish_idx; |
||
89 | return( total_len ); |
||
90 | } |
||
91 | if( buffer[ reduce_idx ] != '\r' ) |
||
92 | { |
||
93 | buffer[ finish_idx++ ] = buffer[ reduce_idx ]; |
||
94 | }; |
||
95 | } |
||
96 | |||
97 | total_len += finish_idx; |
||
98 | buffer += finish_idx; |
||
99 | read_len -= finish_idx; |
||
100 | if( iomode_flags & _ISTTY ) |
||
101 | { |
||
102 | break; |
||
103 | } |
||
104 | } while( read_len != 0 ); |
||
105 | } |
||
106 | return( total_len ); |
||
107 | }>> |