xref: /netbsd-src/usr.bin/indent/indent.h (revision 2dd295436a0082eb4f8d294f4aa73c223413d0f2)
1 /*	$NetBSD: indent.h,v 1.204 2023/06/26 20:03:09 rillig Exp $	*/
2 
3 /*-
4  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
5  *
6  * Copyright (c) 2001 Jens Schweikhardt
7  * All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND
19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE
22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  */
30 /*-
31  * SPDX-License-Identifier: BSD-4-Clause
32  *
33  * Copyright (c) 1985 Sun Microsystems, Inc.
34  * Copyright (c) 1980, 1993
35  *	The Regents of the University of California.  All rights reserved.
36  * All rights reserved.
37  *
38  * Redistribution and use in source and binary forms, with or without
39  * modification, are permitted provided that the following conditions
40  * are met:
41  * 1. Redistributions of source code must retain the above copyright
42  *    notice, this list of conditions and the following disclaimer.
43  * 2. Redistributions in binary form must reproduce the above copyright
44  *    notice, this list of conditions and the following disclaimer in the
45  *    documentation and/or other materials provided with the distribution.
46  * 3. All advertising materials mentioning features or use of this software
47  *    must display the following acknowledgement:
48  *	This product includes software developed by the University of
49  *	California, Berkeley and its contributors.
50  * 4. Neither the name of the University nor the names of its contributors
51  *    may be used to endorse or promote products derived from this software
52  *    without specific prior written permission.
53  *
54  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
55  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
56  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
57  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
58  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
59  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
60  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
61  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
62  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
63  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
64  * SUCH DAMAGE.
65  */
66 
67 #include <ctype.h>
68 #include <stdbool.h>
69 #include <stdio.h>
70 
71 typedef enum lexer_symbol {
72 	lsym_eof,
73 	lsym_preprocessing,	/* the initial '#' of a preprocessing line */
74 	lsym_newline,		/* outside block comments */
75 	lsym_comment,		/* the initial '/ *' or '//' of a comment */
76 
77 	lsym_lparen,
78 	lsym_rparen,
79 	lsym_lbracket,
80 	lsym_rbracket,
81 	lsym_lbrace,
82 	lsym_rbrace,
83 
84 	lsym_period,
85 	lsym_unary_op,		/* e.g. '*', '&', '-' or leading '++' */
86 	lsym_sizeof,
87 	lsym_offsetof,
88 	lsym_postfix_op,	/* trailing '++' or '--' */
89 	lsym_binary_op,		/* e.g. '*', '&', '<<', '&&' or '/=' */
90 	lsym_question,		/* the '?' from a '?:' expression */
91 	lsym_question_colon,	/* the ':' from a '?:' expression */
92 	lsym_comma,
93 
94 	lsym_typedef,
95 	lsym_modifier,		/* modifiers for types, functions, variables */
96 	lsym_tag,		/* 'struct', 'union' or 'enum' */
97 	lsym_type,
98 	lsym_word,		/* identifier, constant or string */
99 	lsym_funcname,		/* name of a function being defined */
100 	lsym_label_colon,	/* the ':' after a label */
101 	lsym_other_colon,	/* bit-fields, generic-association (C11),
102 				 * enum-type-specifier (C23),
103 				 * attribute-prefixed-token (C23),
104 				 * pp-prefixed-parameter (C23 6.10) */
105 	lsym_semicolon,
106 
107 	lsym_case,
108 	lsym_default,
109 	lsym_do,
110 	lsym_else,
111 	lsym_for,
112 	lsym_if,
113 	lsym_switch,
114 	lsym_while,
115 	lsym_return,
116 } lexer_symbol;
117 
118 /*
119  * Structure of the source code, in terms of declarations, statements and
120  * braces; used to determine the indentation level of these parts.
121  */
122 typedef enum parser_symbol {
123 	psym_0,			/* a placeholder; not stored on the stack */
124 	psym_lbrace_block,	/* '{' for a block of code */
125 	psym_lbrace_struct,	/* '{' in 'struct ... { ... }' */
126 	psym_lbrace_union,	/* '{' in 'union ... { ... }' */
127 	psym_lbrace_enum,	/* '{' in 'enum ... { ... }' */
128 	psym_rbrace,		/* not stored on the stack */
129 	psym_decl,
130 	psym_stmt,
131 	psym_for_exprs,		/* 'for' '(' ... ')' */
132 	psym_if_expr,		/* 'if' '(' expr ')' */
133 	psym_if_expr_stmt,	/* 'if' '(' expr ')' stmt */
134 	psym_if_expr_stmt_else,	/* 'if' '(' expr ')' stmt 'else' */
135 	psym_else,		/* 'else'; not stored on the stack */
136 	psym_switch_expr,	/* 'switch' '(' expr ')' */
137 	psym_do,		/* 'do' */
138 	psym_do_stmt,		/* 'do' stmt */
139 	psym_while_expr,	/* 'while' '(' expr ')' */
140 } parser_symbol;
141 
142 /* A range of characters, only null-terminated in debug mode. */
143 struct buffer {
144 	char *s;
145 	size_t len;
146 	size_t cap;
147 };
148 
149 extern FILE *input;
150 extern FILE *output;
151 
152 /*
153  * The current line from the input file, used by the lexer to generate tokens.
154  * To read from the line, start at inp_p and continue up to and including the
155  * next '\n'. To read beyond the '\n', call inp_skip or inp_next, which will
156  * make the next line available, invalidating any pointers into the previous
157  * line.
158  */
159 extern struct buffer inp;
160 extern const char *inp_p;
161 
162 extern struct buffer token;	/* the current token to be processed, is
163 				 * typically copied to the buffer 'code', or in
164 				 * some cases to 'lab'. */
165 
166 extern struct buffer lab;	/* the label or preprocessor directive */
167 extern struct buffer code;	/* the main part of the current line of code,
168 				 * containing declarations or statements */
169 extern struct buffer com;	/* the trailing comment of the line, or the
170 				 * start or end of a multi-line comment, or
171 				 * while in process_comment, a single line of a
172 				 * multi-line comment */
173 
174 extern struct options {
175 	bool blank_line_around_conditional_compilation;
176 	bool blank_line_after_decl_at_top;	/* this is vaguely similar to
177 						 * blank_line_after_decl except
178 						 * that it only applies to the
179 						 * first set of declarations in
180 						 * a procedure (just after the
181 						 * first '{') and it causes a
182 						 * blank line to be generated
183 						 * even if there are no
184 						 * declarations */
185 	bool blank_line_after_decl;
186 	bool blank_line_after_proc;
187 	bool blank_line_before_block_comment;
188 	bool break_after_comma;	/* whether to add a line break after each
189 				 * declarator */
190 	bool brace_same_line;	/* whether a brace should be on same line as an
191 				 * if, while, etc. */
192 	bool blank_after_sizeof;
193 	bool comment_delimiter_on_blank_line;
194 	int decl_comment_column;	/* the column in which comments after
195 					 * declarations should be put */
196 	bool cuddle_else;	/* whether 'else' should cuddle up to '}' */
197 	int continuation_indent;	/* the indentation between the edge of
198 					 * code and continuation lines */
199 	float case_indent;	/* the distance (measured in indentation
200 				 * levels) to indent case labels from the
201 				 * switch statement */
202 	int comment_column;	/* the column in which comments to the right of
203 				 * code should start */
204 	int decl_indent;	/* indentation of identifier in declaration */
205 	bool left_justify_decl;
206 	int unindent_displace;	/* comments not to the right of code will be
207 				 * placed this many indentation levels to the
208 				 * left of code */
209 	bool extra_expr_indent;	/* whether continuation lines from the
210 				 * expression part of "if (e)", "while (e)",
211 				 * "for (e; e; e)" should be indented an extra
212 				 * tab stop so that they are not confused with
213 				 * the code that follows */
214 	bool else_if_in_same_line;
215 	bool function_brace_split;	/* split function declaration and brace
216 					 * onto separate lines */
217 	bool format_col1_comments;	/* whether comments that start in
218 					 * column 1 are to be reformatted (just
219 					 * like comments that begin in later
220 					 * columns) */
221 	bool format_block_comments;	/* whether to reformat comments that
222 					 * begin with '/ * \n' */
223 	bool indent_parameters;
224 	int indent_size;	/* the size of one indentation level */
225 	int block_comment_max_line_length;
226 	int local_decl_indent;	/* like decl_indent but for locals */
227 	bool lineup_to_parens_always;	/* whether to not(?) attempt to keep
228 					 * lined-up code within the margin */
229 	bool lineup_to_parens;	/* whether continued code within parens will be
230 				 * lined up to the open paren */
231 	bool proc_calls_space;	/* whether function calls look like 'foo (bar)'
232 				 * rather than 'foo(bar)' */
233 	bool procnames_start_line;	/* whether the names of functions being
234 					 * defined get placed in column 1 (i.e.
235 					 * a newline is placed between the type
236 					 * of the function and its name) */
237 	bool space_after_cast;	/* "b = (int) a" vs. "b = (int)a" */
238 	bool star_comment_cont;	/* whether comment continuation lines should
239 				 * have stars at the beginning of each line */
240 	bool swallow_optional_blank_lines;
241 	bool auto_typedefs;	/* whether to recognize identifiers ending in
242 				 * "_t" like typedefs */
243 	int tabsize;		/* the size of a tab */
244 	int max_line_length;
245 	bool use_tabs;		/* set true to use tabs for spacing, false uses
246 				 * all spaces */
247 	bool verbose;		/* print configuration to stderr */
248 } opt;
249 
250 extern bool found_err;
251 extern bool had_eof;		/* whether input is exhausted */
252 extern int line_no;		/* the current input line number */
253 extern enum indent_enabled {
254 	indent_on,
255 	indent_off,
256 	indent_last_off_line,
257 } indent_enabled;
258 
259 /* Properties of each level of parentheses or brackets. */
260 struct paren_level {
261 	int indent;		/* indentation of the operand/argument,
262 				 * relative to the enclosing statement; if
263 				 * negative, reflected at -1 */
264 	enum paren_level_cast {
265 		cast_unknown,
266 		cast_maybe,
267 		cast_no,
268 	} cast;			/* whether the parentheses form a type cast */
269 };
270 
271 struct psym_stack {
272 	parser_symbol *sym;
273 	int *ind_level;
274 	size_t len;		/* points to one behind the top of the stack; 1
275 				 * at the top level of the file outside a
276 				 * declaration or statement; 2 at the top level
277 				 */
278 	size_t cap;
279 };
280 
281 /*
282  * The parser state determines the layout of the formatted text.
283  *
284  * At each '#if', the parser state is copied so that the corresponding '#else'
285  * lines start in the same state.
286  *
287  * In a function body, the number of block braces determines the indentation
288  * of statements and declarations.
289  *
290  * In a statement, the number of parentheses or brackets determines the
291  * indentation of follow-up lines.
292  *
293  * In an expression, the token type determine whether to put spaces around.
294  *
295  * In a source file, the types of line determine the vertical spacing, such as
296  * around preprocessing directives or function bodies, or above block
297  * comments.
298  */
299 extern struct parser_state {
300 	lexer_symbol prev_lsym;	/* the previous token, but never comment,
301 				 * newline or preprocessing line */
302 
303 	/* Token classification */
304 
305 	bool in_stmt_or_decl;	/* whether in a statement or a struct
306 				 * declaration or a plain declaration */
307 	bool in_decl;		/* XXX: double-check the exact meaning */
308 	bool in_typedef_decl;
309 	bool in_var_decl;	/* starts at a type name or a '){' from a
310 				 * compound literal; ends at the '(' from a
311 				 * function definition or a ';' outside '{}';
312 				 * when active, '{}' form struct or union
313 				 * declarations, ':' marks a bit-field, and '='
314 				 * starts an initializer */
315 	bool in_init;		/* whether inside an initializer */
316 	int init_level;		/* the number of '{}' in an initializer */
317 	bool line_has_func_def;	/* starts either at the 'name(' from a function
318 				 * definition if it occurs at the beginning of
319 				 * a line, or at the first '*' from inside a
320 				 * declaration when the line starts with words
321 				 * followed by a '(' */
322 	bool in_func_def_params;	/* for old-style functions */
323 	bool line_has_decl;	/* whether this line of code has part of a
324 				 * declaration on it; used for indenting
325 				 * comments */
326 	parser_symbol lbrace_kind;	/* the kind of brace to be pushed to
327 					 * the parser symbol stack next */
328 	parser_symbol spaced_expr_psym;	/* the parser symbol to be shifted
329 					 * after the parenthesized expression
330 					 * from a 'for', 'if', 'switch' or
331 					 * 'while'; or psym_0 */
332 	bool seen_case;		/* whether there was a 'case' or 'default', to
333 				 * properly space the following ':' */
334 	bool prev_paren_was_cast;
335 	int quest_level;	/* when this is positive, we have seen a '?'
336 				 * without the matching ':' in a '?:'
337 				 * expression */
338 
339 	/* Indentation of statements and declarations */
340 
341 	int ind_level;		/* the indentation level for the line that is
342 				 * currently prepared for output */
343 	int ind_level_follow;	/* the level to which ind_level should be set
344 				 * after the current line is printed */
345 	bool line_is_stmt_cont;	/* whether the current line should have an
346 				 * extra indentation level because we are in
347 				 * the middle of a statement */
348 	int decl_level;		/* current nesting level for a structure
349 				 * declaration or an initializer */
350 	int di_stack[20];	/* a stack of structure indentation levels */
351 	bool decl_indent_done;	/* whether the indentation for a declaration
352 				 * has been added to the code buffer. */
353 	int decl_ind;		/* current indentation for declarations */
354 	bool tabs_to_var;	/* true if using tabs to indent to var name */
355 
356 	enum {
357 		eei_no,
358 		eei_maybe,
359 		eei_last
360 	} extra_expr_indent;
361 
362 	struct psym_stack psyms;
363 
364 	/* Spacing inside a statement or declaration */
365 
366 	bool next_unary;	/* whether the following operator should be
367 				 * unary; is used in declarations for '*', as
368 				 * well as in expressions */
369 	bool want_blank;	/* whether the following token should be
370 				 * prefixed by a blank. (Said prefixing is
371 				 * ignored in some cases.) */
372 	int ind_paren_level;	/* the number of parentheses or brackets that
373 				 * is used for indenting a continuation line of
374 				 * a declaration, initializer or statement */
375 	struct paren_stack {
376 		struct paren_level *item;
377 		size_t len;
378 		size_t cap;
379 	} paren;		/* the parentheses or brackets that are
380 				 * currently open; used to indent the remaining
381 				 * lines of the statement, initializer or
382 				 * declaration */
383 
384 	/* Indentation of comments */
385 
386 	int comment_ind;	/* total indentation of the current comment */
387 	int comment_shift;	/* all but the first line of a boxed comment
388 				 * are shifted this much to the right */
389 	bool comment_cont;	/* after the first line of a comment */
390 
391 	/* Vertical spacing */
392 
393 	bool break_after_comma;	/* whether to add a newline after the next
394 				 * comma; used in declarations but not in
395 				 * initializer lists */
396 	bool want_newline;	/* whether the next token should go to a new
397 				 * line; used after 'if (expr)' and in similar
398 				 * situations; tokens like '{' or ';' may
399 				 * ignore this */
400 
401 	enum declaration {
402 		decl_no,	/* no declaration anywhere nearby */
403 		decl_begin,	/* collecting tokens of a declaration */
404 		decl_end,	/* finished a declaration */
405 	} declaration;
406 	bool blank_line_after_decl;
407 
408 	enum {
409 		badp_none,
410 		badp_seen_lbrace,
411 		badp_decl,	/* in an unfinished declaration in the first
412 				 * block of declarations in a function body */
413 		badp_seen_decl,	/* seen the semicolon of a declaration; the
414 				 * next line is a candidate for inserting a
415 				 * blank line above */
416 		badp_yes,	/* this line is a candidate for inserting a
417 				 * blank line above, unless the line turns out
418 				 * to start a declaration */
419 	} badp;			/* insert a blank line before the first
420 				 * statement in a function body */
421 } ps;
422 
423 extern struct output_state {
424 	enum line_kind {
425 		lk_other,
426 		lk_blank,
427 		lk_pre_if,	/* #if, #ifdef, #ifndef */
428 		lk_pre_endif,	/* #endif */
429 		lk_pre_other,	/* #else, #elif, #define, #undef */
430 		lk_stmt_head,	/* the ')' of an incomplete statement such as
431 				 * 'if (expr)' or 'for (expr; expr; expr)' */
432 		lk_func_end,	/* the last '}' of a function body */
433 		lk_block_comment,
434 		lk_case_or_default,
435 	} line_kind;		/* kind of the line that is being prepared for
436 				 * output; is reset to lk_other each time after
437 				 * trying to send a line to the output, even if
438 				 * that line was a suppressed blank line; used
439 				 * for inserting or removing blank lines */
440 	enum line_kind prev_line_kind;	/* the kind of line that was actually
441 					 * sent to the output */
442 
443 	struct buffer indent_off_text;	/* text from between 'INDENT OFF' and
444 					 * 'INDENT ON', both inclusive */
445 } out;
446 
447 
448 #define array_length(array) (sizeof(array) / sizeof((array)[0]))
449 
450 #ifdef debug
451 void debug_printf(const char *, ...) __printflike(1, 2);
452 void debug_println(const char *, ...) __printflike(1, 2);
453 void debug_blank_line(void);
454 void debug_vis_range(const char *, size_t);
455 void debug_parser_state(void);
456 void debug_psyms_stack(const char *);
457 void debug_print_buf(const char *, const struct buffer *);
458 void debug_buffers(void);
459 void parser_state_back_up(struct parser_state *);
460 void parser_state_free(struct parser_state *);
461 extern const char *const lsym_name[];
462 extern const char *const psym_name[];
463 extern const char *const paren_level_cast_name[];
464 extern const char *const line_kind_name[];
465 #define static_unless_debug /* nothing */
466 #else
467 #define debug_noop() do { } while (false)
468 #define	debug_printf(fmt, ...) debug_noop()
469 #define	debug_println(fmt, ...) debug_noop()
470 #define debug_blank_line() debug_noop()
471 #define	debug_vis_range(s, len) debug_noop()
472 #define	debug_parser_state() debug_noop()
473 #define	debug_psyms_stack(situation) debug_noop()
474 #define debug_print_buf(name, buf) debug_noop()
475 #define	debug_buffers() debug_noop()
476 #define static_unless_debug static
477 #endif
478 
479 void register_typename(const char *);
480 int compute_code_indent(void);
481 int compute_label_indent(void);
482 int ind_add(int, const char *, size_t);
483 
484 void inp_skip(void);
485 char inp_next(void);
486 void finish_output(void);
487 
488 lexer_symbol lexi(void);
489 void diag(int, const char *, ...) __printflike(2, 3);
490 void output_line(void);
491 void inp_read_line(void);
492 void parse(parser_symbol);
493 void process_comment(void);
494 void set_option(const char *, const char *);
495 void load_profile_files(const char *);
496 void ps_push(parser_symbol, bool);
497 
498 void *nonnull(void *);
499 
500 void buf_add_char(struct buffer *, char);
501 void buf_add_chars(struct buffer *, const char *, size_t);
502 
503 static inline bool
504 ch_isalnum(char ch)
505 {
506 	return isalnum((unsigned char)ch) != 0;
507 }
508 
509 static inline bool
510 ch_isalpha(char ch)
511 {
512 	return isalpha((unsigned char)ch) != 0;
513 }
514 
515 static inline bool
516 ch_isblank(char ch)
517 {
518 	return ch == ' ' || ch == '\t';
519 }
520 
521 static inline bool
522 ch_isdigit(char ch)
523 {
524 	return '0' <= ch && ch <= '9';
525 }
526 
527 static inline bool
528 ch_isspace(char ch)
529 {
530 	return isspace((unsigned char)ch) != 0;
531 }
532 
533 static inline int
534 next_tab(int ind)
535 {
536 	return ind - ind % opt.tabsize + opt.tabsize;
537 }
538 
539 #ifdef debug
540 void buf_terminate(struct buffer *);
541 #else
542 #define buf_terminate(buf) debug_noop()
543 #endif
544 
545 static inline void
546 buf_clear(struct buffer *buf)
547 {
548 	buf->len = 0;
549 	buf_terminate(buf);
550 }
551