2 * Copyright (c) 1985 Sun Microsystems, Inc.
3 * Copyright (c) 1980, 1993
4 * The Regents of the University of California. All rights reserved.
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. All advertising materials mentioning features or use of this software
16 * must display the following acknowledgement:
17 * This product includes software developed by the University of
18 * California, Berkeley and its contributors.
19 * 4. Neither the name of the University nor the names of its contributors
20 * may be used to endorse or promote products derived from this software
21 * without specific prior written permission.
23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35 * @(#)parse.c 8.1 (Berkeley) 6/6/93
36 * $FreeBSD: src/usr.bin/indent/parse.c,v 1.10 2003/06/15 09:28:17 charnier Exp $
40 #include "indent_globs.h"
41 #include "indent_codes.h"
44 static void reduce(void);
47 parse(int tk
) /* tk: the code for the construct scanned */
52 printf("%2d - %s\n", tk
, token
);
55 while (ps
.p_stack
[ps
.tos
] == ifhead
&& tk
!= elselit
) {
56 /* true if we have an if without an else */
57 ps
.p_stack
[ps
.tos
] = stmt
; /* apply the if(..) stmt ::= stmt
59 reduce(); /* see if this allows any reduction */
63 switch (tk
) { /* go on and figure out what to do with the
66 case decl
: /* scanned a declaration word */
67 ps
.search_brace
= btype_2
;
68 /* indicate that following brace should be on same line */
69 if (ps
.p_stack
[ps
.tos
] != decl
) { /* only put one declaration
71 break_comma
= true; /* while in declaration, newline should be
72 * forced after comma */
73 ps
.p_stack
[++ps
.tos
] = decl
;
74 ps
.il
[ps
.tos
] = ps
.i_l_follow
;
76 if (ps
.ljust_decl
) {/* only do if we want left justified
79 for (i
= ps
.tos
- 1; i
> 0; --i
)
80 if (ps
.p_stack
[i
] == decl
)
81 ++ps
.ind_level
; /* indentation is number of
82 * declaration levels deep we are */
83 ps
.i_l_follow
= ps
.ind_level
;
88 case ifstmt
: /* scanned if (...) */
89 if (ps
.p_stack
[ps
.tos
] == elsehead
&& ps
.else_if
) /* "else if ..." */
90 ps
.i_l_follow
= ps
.il
[ps
.tos
];
91 case dolit
: /* 'do' */
92 case forstmt
: /* for (...) */
93 ps
.p_stack
[++ps
.tos
] = tk
;
94 ps
.il
[ps
.tos
] = ps
.ind_level
= ps
.i_l_follow
;
95 ++ps
.i_l_follow
; /* subsequent statements should be indented 1 */
96 ps
.search_brace
= btype_2
;
99 case lbrace
: /* scanned { */
100 break_comma
= false; /* don't break comma in an initial list */
101 if (ps
.p_stack
[ps
.tos
] == stmt
|| ps
.p_stack
[ps
.tos
] == decl
102 || ps
.p_stack
[ps
.tos
] == stmtl
)
103 ++ps
.i_l_follow
; /* it is a random, isolated stmt group or a
106 if (s_code
== e_code
) {
108 * only do this if there is nothing on the line
112 * it is a group as part of a while, for, etc.
114 if (ps
.p_stack
[ps
.tos
] == swstmt
&& ps
.case_indent
>= 1)
117 * for a switch, brace should be two levels out from the code
122 ps
.p_stack
[++ps
.tos
] = lbrace
;
123 ps
.il
[ps
.tos
] = ps
.ind_level
;
124 ps
.p_stack
[++ps
.tos
] = stmt
;
125 /* allow null stmt between braces */
126 ps
.il
[ps
.tos
] = ps
.i_l_follow
;
129 case whilestmt
: /* scanned while (...) */
130 if (ps
.p_stack
[ps
.tos
] == dohead
) {
131 /* it is matched with do stmt */
132 ps
.ind_level
= ps
.i_l_follow
= ps
.il
[ps
.tos
];
133 ps
.p_stack
[++ps
.tos
] = whilestmt
;
134 ps
.il
[ps
.tos
] = ps
.ind_level
= ps
.i_l_follow
;
136 else { /* it is a while loop */
137 ps
.p_stack
[++ps
.tos
] = whilestmt
;
138 ps
.il
[ps
.tos
] = ps
.i_l_follow
;
140 ps
.search_brace
= btype_2
;
145 case elselit
: /* scanned an else */
147 if (ps
.p_stack
[ps
.tos
] != ifhead
)
148 diag2(1, "Unmatched 'else'");
150 ps
.ind_level
= ps
.il
[ps
.tos
]; /* indentation for else should
151 * be same as for if */
152 ps
.i_l_follow
= ps
.ind_level
+ 1; /* everything following should
154 ps
.p_stack
[ps
.tos
] = elsehead
;
155 /* remember if with else */
156 ps
.search_brace
= btype_2
| ps
.else_if
;
160 case rbrace
: /* scanned a } */
161 /* stack should have <lbrace> <stmt> or <lbrace> <stmtl> */
162 if (ps
.p_stack
[ps
.tos
- 1] == lbrace
) {
163 ps
.ind_level
= ps
.i_l_follow
= ps
.il
[--ps
.tos
];
164 ps
.p_stack
[ps
.tos
] = stmt
;
167 diag2(1, "Statement nesting error");
170 case swstmt
: /* had switch (...) */
171 ps
.p_stack
[++ps
.tos
] = swstmt
;
172 ps
.cstk
[ps
.tos
] = case_ind
;
173 /* save current case indent level */
174 ps
.il
[ps
.tos
] = ps
.i_l_follow
;
175 case_ind
= ps
.i_l_follow
+ ps
.case_indent
; /* cases should be one
178 ps
.i_l_follow
+= ps
.case_indent
+ 1; /* statements should be two
180 ps
.search_brace
= btype_2
;
183 case semicolon
: /* this indicates a simple stmt */
184 break_comma
= false; /* turn off flag to break after commas in a
186 ps
.p_stack
[++ps
.tos
] = stmt
;
187 ps
.il
[ps
.tos
] = ps
.ind_level
;
190 default: /* this is an error */
191 diag2(1, "Unknown code to parser");
195 } /* end of switch */
197 reduce(); /* see if any reduction can be done */
200 for (i
= 1; i
<= ps
.tos
; ++i
)
201 printf("(%d %d)", ps
.p_stack
[i
], ps
.il
[i
]);
211 * FUNCTION: Implements the reduce part of the parsing algorithm
213 * ALGORITHM: The following reductions are done. Reductions are repeated
214 * until no more are possible.
217 * <stmt> <stmt> <stmtl>
218 * <stmtl> <stmt> <stmtl>
221 * switch <stmt> <stmt>
223 * "ifelse" <stmt> <stmt>
225 * while <stmt> <stmt>
226 * "dostmt" while <stmt>
228 * On each reduction, ps.i_l_follow (the indentation for the following line)
229 * is set to the indentation level associated with the old TOS.
235 * GLOBALS: ps.cstk ps.i_l_follow = ps.il ps.p_stack = ps.tos =
241 * HISTORY: initial coding November 1976 D A Willcox of CAC
244 /*----------------------------------------------*\
246 \*----------------------------------------------*/
252 for (;;) { /* keep looping until there is nothing left to
255 switch (ps
.p_stack
[ps
.tos
]) {
258 switch (ps
.p_stack
[ps
.tos
- 1]) {
262 /* stmtl stmt or stmt stmt */
263 ps
.p_stack
[--ps
.tos
] = stmtl
;
266 case dolit
: /* <do> <stmt> */
267 ps
.p_stack
[--ps
.tos
] = dohead
;
268 ps
.i_l_follow
= ps
.il
[ps
.tos
];
273 ps
.p_stack
[--ps
.tos
] = ifhead
;
276 ps
.p_stack
[i
] != stmt
278 ps
.p_stack
[i
] != stmtl
280 ps
.p_stack
[i
] != lbrace
283 ps
.i_l_follow
= ps
.il
[i
];
285 * for the time being, we will assume that there is no else on
286 * this if, and set the indentation level accordingly. If an
287 * else is scanned, it will be fixed up later
292 /* <switch> <stmt> */
293 case_ind
= ps
.cstk
[ps
.tos
- 1];
295 case decl
: /* finish of a declaration */
297 /* <<if> <stmt> else> <stmt> */
302 ps
.p_stack
[--ps
.tos
] = stmt
;
303 ps
.i_l_follow
= ps
.il
[ps
.tos
];
306 default: /* <anything else> <stmt> */
309 } /* end of section for <stmt> on top of stack */
312 case whilestmt
: /* while (...) on top */
313 if (ps
.p_stack
[ps
.tos
- 1] == dohead
) {
314 /* it is termination of a do while */
321 default: /* anything else on top */