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