Commit | Line | Data |
---|---|---|
593eb738 HE |
1 | \ READ-LINE and WRITE-LINE |
2 | \ | |
3 | \ This file is in the public domain. | |
4 | \ | |
5 | ||
6 | private{ | |
7 | ||
8 | 10 constant \n | |
9 | 13 constant \r | |
10 | ||
11 | \ Unread one char from file FILEID. | |
12 | : UNREAD ( fileid -- ior ) | |
13 | { f } | |
14 | f file-position ( ud ior ) | |
15 | ?dup | |
16 | IF nip nip \ IO error | |
17 | ELSE 1 s>d d- f reposition-file | |
18 | THEN | |
19 | ; | |
20 | ||
21 | \ Read the next available char from file FILEID and if it is a \n then | |
22 | \ skip it; otherwise unread it. IOR is non-zero if an error occured. | |
23 | \ C-ADDR is a buffer that can hold at least on char. | |
24 | : SKIP-\n ( c-addr fileid -- ior ) | |
aad4537d HE |
25 | { a f } |
26 | a 1 f read-file ( u ior ) | |
27 | ?dup | |
28 | IF \ Read error? | |
29 | nip | |
30 | ELSE ( u ) | |
31 | 0= | |
32 | IF \ End of file? | |
33 | 0 | |
34 | ELSE | |
35 | a c@ \n = ( is-it-a-\n? ) | |
36 | IF 0 | |
37 | ELSE f unread | |
38 | THEN | |
39 | THEN | |
40 | THEN | |
593eb738 HE |
41 | ; |
42 | ||
43 | \ This is just s\" \n" but s\" isn't yet available. | |
44 | create (LINE-TERMINATOR) \n c, | |
45 | : LINE-TERMINATOR ( -- c-addr u ) (line-terminator) 1 ; | |
46 | ||
47 | }private | |
48 | ||
49 | ||
50 | \ This treats \n, \r\n, and \r as line terminator. Reading is done | |
51 | \ one char at a time with READ-FILE hence READ-FILE should probably do | |
52 | \ some form of buffering for good efficiency. | |
53 | : READ-LINE ( c-addr u1 fileid -- u2 flag ior ) | |
aad4537d HE |
54 | { a u f } |
55 | u 0 ?DO | |
56 | a i chars + 1 f read-file ( u ior' ) | |
57 | ?dup IF nip i false rot UNLOOP EXIT THEN \ Read error? ( u ) | |
58 | 0= IF i i 0> 0 UNLOOP EXIT THEN \ End of file? ( ) | |
59 | a i chars + c@ | |
60 | CASE | |
61 | \n OF i true 0 UNLOOP EXIT ENDOF | |
62 | \r OF | |
63 | \ Detect \r\n | |
64 | a i 1+ chars + f skip-\n ( ior ) | |
65 | ?dup IF i false rot UNLOOP EXIT THEN \ IO Error? ( ) | |
66 | i true 0 UNLOOP EXIT | |
67 | ENDOF | |
68 | ENDCASE | |
69 | LOOP | |
70 | \ Line doesn't fit in buffer | |
71 | u true 0 | |
593eb738 HE |
72 | ; |
73 | ||
74 | : WRITE-LINE ( c-addr u fileid -- ior ) | |
aad4537d HE |
75 | { f } |
76 | f write-file ( ior ) | |
77 | ?dup | |
78 | IF \ IO error | |
79 | ELSE line-terminator f write-file | |
80 | THEN | |
593eb738 HE |
81 | ; |
82 | ||
83 | privatize |