1 | /*****************************************************************************/ |
2 | /* */ |
3 | /* repeat.c */ |
4 | /* */ |
5 | /* Handle the .REPEAT pseudo instruction */ |
6 | /* */ |
7 | /* */ |
8 | /* */ |
9 | /* (C) 2000-2011, Ullrich von Bassewitz */ |
10 | /* Roemerstrasse 52 */ |
11 | /* D-70794 Filderstadt */ |
12 | /* EMail: uz@cc65.org */ |
13 | /* */ |
14 | /* */ |
15 | /* This software is provided 'as-is', without any expressed or implied */ |
16 | /* warranty. In no event will the authors be held liable for any damages */ |
17 | /* arising from the use of this software. */ |
18 | /* */ |
19 | /* Permission is granted to anyone to use this software for any purpose, */ |
20 | /* including commercial applications, and to alter it and redistribute it */ |
21 | /* freely, subject to the following restrictions: */ |
22 | /* */ |
23 | /* 1. The origin of this software must not be misrepresented; you must not */ |
24 | /* claim that you wrote the original software. If you use this software */ |
25 | /* in a product, an acknowledgment in the product documentation would be */ |
26 | /* appreciated but is not required. */ |
27 | /* 2. Altered source versions must be plainly marked as such, and must not */ |
28 | /* be misrepresented as being the original software. */ |
29 | /* 3. This notice may not be removed or altered from any source */ |
30 | /* distribution. */ |
31 | /* */ |
32 | /*****************************************************************************/ |
33 | |
34 | |
35 | |
36 | #include <string.h> |
37 | |
38 | /* common */ |
39 | #include "xmalloc.h" |
40 | |
41 | /* ca65 */ |
42 | #include "error.h" |
43 | #include "expr.h" |
44 | #include "nexttok.h" |
45 | #include "toklist.h" |
46 | #include "repeat.h" |
47 | |
48 | |
49 | |
50 | /*****************************************************************************/ |
51 | /* Code */ |
52 | /*****************************************************************************/ |
53 | |
54 | |
55 | |
56 | static TokList* CollectRepeatTokens (void) |
57 | /* Collect all tokens inside the .REPEAT body in a token list and return |
58 | ** this list. In case of errors, NULL is returned. |
59 | */ |
60 | { |
61 | /* Create the token list */ |
62 | TokList* List = NewTokList (); |
63 | |
64 | /* Read the token list */ |
65 | unsigned Repeats = 0; |
66 | while (Repeats != 0 || CurTok.Tok != TOK_ENDREP) { |
67 | |
68 | /* Check for end of input */ |
69 | if (CurTok.Tok == TOK_EOF) { |
70 | Error ("Unexpected end of file" ); |
71 | FreeTokList (List); |
72 | return 0; |
73 | } |
74 | |
75 | /* Collect all tokens in the list */ |
76 | AddCurTok (List); |
77 | |
78 | /* Check for and count nested .REPEATs */ |
79 | if (CurTok.Tok == TOK_REPEAT) { |
80 | ++Repeats; |
81 | } else if (CurTok.Tok == TOK_ENDREP) { |
82 | --Repeats; |
83 | } |
84 | |
85 | /* Get the next token */ |
86 | NextTok (); |
87 | } |
88 | |
89 | /* Eat the closing .ENDREP */ |
90 | NextTok (); |
91 | |
92 | /* Return the list of collected tokens */ |
93 | return List; |
94 | } |
95 | |
96 | |
97 | |
98 | static void RepeatTokenCheck (TokList* L) |
99 | /* Called each time a token from a repeat token list is set. Is used to check |
100 | ** for and replace identifiers that are the repeat counter. |
101 | */ |
102 | { |
103 | if (CurTok.Tok == TOK_IDENT && |
104 | L->Data != 0 && |
105 | SB_CompareStr (&CurTok.SVal, L->Data) == 0) { |
106 | /* Must replace by the repeat counter */ |
107 | CurTok.Tok = TOK_INTCON; |
108 | CurTok.IVal = L->RepCount; |
109 | } |
110 | } |
111 | |
112 | |
113 | |
114 | void ParseRepeat (void) |
115 | /* Parse and handle the .REPEAT statement */ |
116 | { |
117 | char* Name; |
118 | TokList* List; |
119 | |
120 | /* Repeat count follows */ |
121 | long RepCount = ConstExpression (); |
122 | if (RepCount < 0) { |
123 | Error ("Range error" ); |
124 | RepCount = 0; |
125 | } |
126 | |
127 | /* Optional there is a comma and a counter variable */ |
128 | Name = 0; |
129 | if (CurTok.Tok == TOK_COMMA) { |
130 | |
131 | /* Skip the comma */ |
132 | NextTok (); |
133 | |
134 | /* Check for an identifier */ |
135 | if (CurTok.Tok != TOK_IDENT) { |
136 | ErrorSkip ("Identifier expected" ); |
137 | } else { |
138 | /* Remember the name and skip it */ |
139 | SB_Terminate (&CurTok.SVal); |
140 | Name = xstrdup (SB_GetConstBuf (&CurTok.SVal)); |
141 | NextTok (); |
142 | } |
143 | } |
144 | |
145 | /* Switch to raw token mode, then skip the separator */ |
146 | EnterRawTokenMode (); |
147 | ConsumeSep (); |
148 | |
149 | /* Read the token list */ |
150 | List = CollectRepeatTokens (); |
151 | |
152 | /* If we had an error, bail out */ |
153 | if (List == 0) { |
154 | xfree (Name); |
155 | goto Done; |
156 | } |
157 | |
158 | /* Update the token list for replay */ |
159 | List->RepMax = (unsigned) RepCount; |
160 | List->Data = Name; |
161 | List->Check = RepeatTokenCheck; |
162 | |
163 | /* If the list is empty, or repeat count zero, there is nothing |
164 | ** to repeat. |
165 | */ |
166 | if (List->Count == 0 || RepCount == 0) { |
167 | FreeTokList (List); |
168 | goto Done; |
169 | } |
170 | |
171 | /* Read input from the repeat descriptor */ |
172 | PushTokList (List, ".REPEAT" ); |
173 | |
174 | Done: |
175 | /* Switch out of raw token mode */ |
176 | LeaveRawTokenMode (); |
177 | } |
178 | |