Add support for multi-line ( comments
[pforth] / fth / file.fth
... / ...
CommitLineData
1\ READ-LINE and WRITE-LINE
2\
3\ This code is part of pForth.
4\
5\ The pForth software code is dedicated to the public domain,
6\ and any third party may reproduce, distribute and modify
7\ the pForth software code or any derivative works thereof
8\ without any compensation or license. The pForth software
9\ code is provided on an "as is" basis without any warranty
10\ of any kind, including, without limitation, the implied
11\ warranties of merchantability and fitness for a particular
12\ purpose and their equivalents under the laws of any jurisdiction.
13
14private{
15
1610 constant \N
1713 constant \R
18
19\ Unread one char from file FILEID.
20: UNREAD { fileid -- ior }
21 fileid file-position ( ud ior )
22 ?dup
23 IF nip nip \ IO error
24 ELSE 1 s>d d- fileid reposition-file
25 THEN
26;
27
28\ Read the next available char from file FILEID and if it is a \n then
29\ skip it; otherwise unread it. IOR is non-zero if an error occured.
30\ C-ADDR is a buffer that can hold at least one char.
31: SKIP-\N { c-addr fileid -- ior }
32 c-addr 1 fileid read-file ( u ior )
33 ?dup
34 IF \ Read error?
35 nip
36 ELSE ( u )
37 0=
38 IF \ End of file?
39 0
40 ELSE
41 c-addr c@ \n = ( is-it-a-\n? )
42 IF 0
43 ELSE fileid unread
44 THEN
45 THEN
46 THEN
47;
48
49\ This is just s\" \n" but s\" isn't yet available.
50create (LINE-TERMINATOR) \n c,
51: LINE-TERMINATOR ( -- c-addr u ) (line-terminator) 1 ;
52
53\ Standard throw code
54\ See: http://lars.nocrew.org/forth2012/exception.html#table:throw
55-72 constant THROW_RENAME_FILE
56
57\ Copy the string C-ADDR/U1 to C-ADDR2 and append a NUL.
58: PLACE-CSTR ( c-addr1 u1 c-addr2 -- )
59 2dup 2>r ( c-addr1 u1 c-addr2 ) ( r: u1 c-addr2 )
60 swap cmove ( ) ( r: u1 c-addr2 )
61 0 2r> + c! ( )
62;
63
64: MULTI-LINE-COMMENT ( "comment<rparen>" -- )
65 BEGIN
66 >in @ ')' parse ( >in c-addr len )
67 nip + >in @ = ( delimiter-not-found? )
68 WHILE ( )
69 refill 0= IF EXIT THEN ( )
70 REPEAT
71
72;
73
74}private
75
76\ This treats \n, \r\n, and \r as line terminator. Reading is done
77\ one char at a time with READ-FILE hence READ-FILE should probably do
78\ some form of buffering for good efficiency.
79: READ-LINE ( c-addr u1 fileid -- u2 flag ior )
80 { a u f }
81 u 0 ?DO
82 a i chars + 1 f read-file ( u ior' )
83 ?dup IF nip i false rot UNLOOP EXIT THEN \ Read error? ( u )
84 0= IF i i 0<> 0 UNLOOP EXIT THEN \ End of file? ( )
85 a i chars + c@
86 CASE
87 \n OF i true 0 UNLOOP EXIT ENDOF
88 \r OF
89 \ Detect \r\n
90 a i chars + f skip-\n ( ior )
91 ?dup IF i false rot UNLOOP EXIT THEN \ IO Error? ( )
92 i true 0 UNLOOP EXIT
93 ENDOF
94 ENDCASE
95 LOOP
96 \ Line doesn't fit in buffer
97 u true 0
98;
99
100: WRITE-LINE ( c-addr u fileid -- ior )
101 { f }
102 f write-file ( ior )
103 ?dup
104 IF \ IO error
105 ELSE line-terminator f write-file
106 THEN
107;
108
109: RENAME-FILE ( c-addr1 u1 c-addr2 u2 -- ior )
110 { a1 u1 a2 u2 | new }
111 \ Convert the file-names to C-strings by copying them after HERE.
112 a1 u1 here place-cstr
113 here u1 1+ chars + to new
114 a2 u2 new place-cstr
115 here new (rename-file) 0=
116 IF 0
117 ELSE throw_rename_file
118 THEN
119;
120
121: ( ( "comment<rparen>" -- )
122 source-id
123 CASE
124 -1 OF postpone ( ENDOF
125 0 OF postpone ( ENDOF
126 multi-line-comment
127 ENDCASE
128; immediate
129
130privatize