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indent.c revision 1.13
      1 /*	$NetBSD: indent.c,v 1.13 2002/05/26 22:53:38 wiz Exp $	*/
      2 
      3 /*
      4  * Copyright (c) 1980, 1993
      5  *	The Regents of the University of California.  All rights reserved.
      6  * Copyright (c) 1976 Board of Trustees of the University of Illinois.
      7  * Copyright (c) 1985 Sun Microsystems, Inc.
      8  * All rights reserved.
      9  *
     10  * Redistribution and use in source and binary forms, with or without
     11  * modification, are permitted provided that the following conditions
     12  * are met:
     13  * 1. Redistributions of source code must retain the above copyright
     14  *    notice, this list of conditions and the following disclaimer.
     15  * 2. Redistributions in binary form must reproduce the above copyright
     16  *    notice, this list of conditions and the following disclaimer in the
     17  *    documentation and/or other materials provided with the distribution.
     18  * 3. All advertising materials mentioning features or use of this software
     19  *    must display the following acknowledgement:
     20  *	This product includes software developed by the University of
     21  *	California, Berkeley and its contributors.
     22  * 4. Neither the name of the University nor the names of its contributors
     23  *    may be used to endorse or promote products derived from this software
     24  *    without specific prior written permission.
     25  *
     26  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     27  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     28  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     29  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     30  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     31  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     32  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     33  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     34  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     35  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     36  * SUCH DAMAGE.
     37  */
     38 
     39 #include <sys/cdefs.h>
     40 #ifndef lint
     41 __COPYRIGHT("@(#) Copyright (c) 1985 Sun Microsystems, Inc.\n\
     42 @(#) Copyright (c) 1976 Board of Trustees of the University of Illinois.\n\
     43 @(#) Copyright (c) 1980, 1993\n\
     44 	The Regents of the University of California.  All rights reserved.\n");
     45 #endif				/* not lint */
     46 
     47 #ifndef lint
     48 #if 0
     49 static char sccsid[] = "@(#)indent.c	5.17 (Berkeley) 6/7/93";
     50 #else
     51 __RCSID("$NetBSD: indent.c,v 1.13 2002/05/26 22:53:38 wiz Exp $");
     52 #endif
     53 #endif				/* not lint */
     54 
     55 #include <sys/param.h>
     56 #include <ctype.h>
     57 #include <err.h>
     58 #include <errno.h>
     59 #include <fcntl.h>
     60 #include <stdio.h>
     61 #include <stdlib.h>
     62 #include <string.h>
     63 #include <unistd.h>
     64 #define EXTERN
     65 #include "indent_globs.h"
     66 #undef  EXTERN
     67 #include "indent_codes.h"
     68 
     69 char   *in_name = "Standard Input";	/* will always point to name of input
     70 					 * file */
     71 char   *out_name = "Standard Output";	/* will always point to name of output
     72 					 * file */
     73 char    bakfile[MAXPATHLEN] = "";
     74 
     75 int main(int, char **);
     76 
     77 int
     78 main(int argc, char **argv)
     79 {
     80 
     81 	extern int found_err;	/* flag set in diag() on error */
     82 	int     dec_ind;	/* current indentation for declarations */
     83 	int     di_stack[20];	/* a stack of structure indentation levels */
     84 	int     flushed_nl;	/* used when buffering up comments to remember
     85 				 * that a newline was passed over */
     86 	int     force_nl;	/* when true, code must be broken */
     87 	int     hd_type;	/* used to store type of stmt for if (...),
     88 				 * for (...), etc */
     89 	int     i;		/* local loop counter */
     90 	int     scase;		/* set to true when we see a case, so we will
     91 				 * know what to do with the following colon */
     92 	int     sp_sw;		/* when true, we are in the expressin of
     93 				 * if(...), while(...), etc. */
     94 	int     squest;		/* when this is positive, we have seen a ?
     95 				 * without the matching : in a <c>?<s>:<s>
     96 				 * construct */
     97 	char   *t_ptr;		/* used for copying tokens */
     98 	int     type_code;	/* the type of token, returned by lexi */
     99 
    100 	int     last_else = 0;	/* true iff last keyword was an else */
    101 
    102 
    103 	/*-----------------------------------------------*\
    104         |		      INITIALIZATION		      |
    105         \*-----------------------------------------------*/
    106 
    107 
    108 	hd_type = 0;
    109 	ps.p_stack[0] = stmt;	/* this is the parser's stack */
    110 	ps.last_nl = true;	/* this is true if the last thing scanned was
    111 				 * a newline */
    112 	ps.last_token = semicolon;
    113 	combuf = (char *) malloc(bufsize);
    114 	labbuf = (char *) malloc(bufsize);
    115 	codebuf = (char *) malloc(bufsize);
    116 	tokenbuf = (char *) malloc(bufsize);
    117 	l_com = combuf + bufsize - 5;
    118 	l_lab = labbuf + bufsize - 5;
    119 	l_code = codebuf + bufsize - 5;
    120 	l_token = tokenbuf + bufsize - 5;
    121 	combuf[0] = codebuf[0] = labbuf[0] = ' ';	/* set up code, label,
    122 							 * and comment buffers */
    123 	combuf[1] = codebuf[1] = labbuf[1] = '\0';
    124 	ps.else_if = 1;		/* Default else-if special processing to on */
    125 	s_lab = e_lab = labbuf + 1;
    126 	s_code = e_code = codebuf + 1;
    127 	s_com = e_com = combuf + 1;
    128 	s_token = e_token = tokenbuf + 1;
    129 
    130 	in_buffer = (char *) malloc(10);
    131 	in_buffer_limit = in_buffer + 8;
    132 	buf_ptr = buf_end = in_buffer;
    133 	line_no = 1;
    134 	had_eof = ps.in_decl = ps.decl_on_line = break_comma = false;
    135 	sp_sw = force_nl = false;
    136 	ps.in_or_st = false;
    137 	ps.bl_line = true;
    138 	dec_ind = 0;
    139 	di_stack[ps.dec_nest = 0] = 0;
    140 	ps.want_blank = ps.in_stmt = ps.ind_stmt = false;
    141 
    142 
    143 	scase = ps.pcase = false;
    144 	squest = 0;
    145 	sc_end = 0;
    146 	bp_save = 0;
    147 	be_save = 0;
    148 
    149 	output = 0;
    150 
    151 
    152 
    153 	/*--------------------------------------------------*\
    154         |   		COMMAND LINE SCAN		 |
    155         \*--------------------------------------------------*/
    156 
    157 #ifdef undef
    158 	max_col = 78;		/* -l78 */
    159 	lineup_to_parens = 1;	/* -lp */
    160 	ps.ljust_decl = 0;	/* -ndj */
    161 	ps.com_ind = 33;	/* -c33 */
    162 	star_comment_cont = 1;	/* -sc */
    163 	ps.ind_size = 8;	/* -i8 */
    164 	verbose = 0;
    165 	ps.decl_indent = 16;	/* -di16 */
    166 	ps.indent_parameters = 1;	/* -ip */
    167 	ps.decl_com_ind = 0;	/* if this is not set to some positive value
    168 				 * by an arg, we will set this equal to
    169 				 * ps.com_ind */
    170 	btype_2 = 1;		/* -br */
    171 	cuddle_else = 1;	/* -ce */
    172 	ps.unindent_displace = 0;	/* -d0 */
    173 	ps.case_indent = 0;	/* -cli0 */
    174 	format_col1_comments = 1;	/* -fc1 */
    175 	procnames_start_line = 1;	/* -psl */
    176 	proc_calls_space = 0;	/* -npcs */
    177 	comment_delimiter_on_blankline = 1;	/* -cdb */
    178 	ps.leave_comma = 1;	/* -nbc */
    179 #endif
    180 
    181 	for (i = 1; i < argc; ++i)
    182 		if (strcmp(argv[i], "-npro") == 0)
    183 			break;
    184 	set_defaults();
    185 	if (i >= argc)
    186 		set_profile();
    187 
    188 	for (i = 1; i < argc; ++i) {
    189 
    190 		/*
    191 		 * look thru args (if any) for changes to defaults
    192 		 */
    193 		if (argv[i][0] != '-') {	/* no flag on parameter */
    194 			if (input == 0) {	/* we must have the input file */
    195 				in_name = argv[i];	/* remember name of
    196 							 * input file */
    197 				input = fopen(in_name, "r");
    198 				if (input == 0)	/* check for open error */
    199 					err(1, "%s", in_name);
    200 				continue;
    201 			} else
    202 				if (output == 0) {	/* we have the output
    203 							 * file */
    204 					out_name = argv[i];	/* remember name of
    205 								 * output file */
    206 					if (strcmp(in_name, out_name) == 0) {	/* attempt to overwrite
    207 										 * the file */
    208 						fprintf(stderr, "indent: input and output files must be different\n");
    209 						exit(1);
    210 					}
    211 					output = fopen(out_name, "w");
    212 					if (output == 0)	/* check for create
    213 								 * error */
    214 						err(1, "%s", out_name);
    215 					continue;
    216 				}
    217 			fprintf(stderr, "indent: unknown parameter: %s\n", argv[i]);
    218 			exit(1);
    219 		} else
    220 			set_option(argv[i]);
    221 	}			/* end of for */
    222 	if (input == 0) {
    223 		input = stdin;
    224 	}
    225 	if (output == 0) {
    226 		if (troff || input == stdin)
    227 			output = stdout;
    228 		else {
    229 			out_name = in_name;
    230 			bakcopy();
    231 		}
    232 	}
    233 	if (ps.com_ind <= 1)
    234 		ps.com_ind = 2;	/* dont put normal comments before column 2 */
    235 	if (troff) {
    236 		if (bodyf.font[0] == 0)
    237 			parsefont(&bodyf, "R");
    238 		if (scomf.font[0] == 0)
    239 			parsefont(&scomf, "I");
    240 		if (blkcomf.font[0] == 0)
    241 			blkcomf = scomf, blkcomf.size += 2;
    242 		if (boxcomf.font[0] == 0)
    243 			boxcomf = blkcomf;
    244 		if (stringf.font[0] == 0)
    245 			parsefont(&stringf, "L");
    246 		if (keywordf.font[0] == 0)
    247 			parsefont(&keywordf, "B");
    248 		writefdef(&bodyf, 'B');
    249 		writefdef(&scomf, 'C');
    250 		writefdef(&blkcomf, 'L');
    251 		writefdef(&boxcomf, 'X');
    252 		writefdef(&stringf, 'S');
    253 		writefdef(&keywordf, 'K');
    254 	}
    255 	if (block_comment_max_col <= 0)
    256 		block_comment_max_col = max_col;
    257 	if (ps.decl_com_ind <= 0)	/* if not specified by user, set this */
    258 		ps.decl_com_ind = ps.ljust_decl ? (ps.com_ind <= 10 ? 2 : ps.com_ind - 8) : ps.com_ind;
    259 	if (continuation_indent == 0)
    260 		continuation_indent = ps.ind_size;
    261 	fill_buffer();		/* get first batch of stuff into input buffer */
    262 
    263 	parse(semicolon);
    264 	{
    265 		char   *p = buf_ptr;
    266 		int     col = 1;
    267 
    268 		while (1) {
    269 			if (*p == ' ')
    270 				col++;
    271 			else
    272 				if (*p == '\t')
    273 					col = ((col - 1) & ~7) + 9;
    274 				else
    275 					break;
    276 			p++;
    277 		}
    278 		if (col > ps.ind_size)
    279 			ps.ind_level = ps.i_l_follow = col / ps.ind_size;
    280 	}
    281 	if (troff) {
    282 		char   *p = in_name, *beg = in_name;
    283 
    284 		while (*p)
    285 			if (*p++ == '/')
    286 				beg = p;
    287 		fprintf(output, ".Fn \"%s\"\n", beg);
    288 	}
    289 	/*
    290          * START OF MAIN LOOP
    291          */
    292 
    293 	while (1) {		/* this is the main loop.  it will go until we
    294 				 * reach eof */
    295 		int     is_procname;
    296 
    297 		type_code = lexi();	/* lexi reads one token.  The actual
    298 					 * characters read are stored in
    299 					 * "token". lexi returns a code
    300 					 * indicating the type of token */
    301 		is_procname = ps.procname[0];
    302 
    303 		/*
    304 		 * The following code moves everything following an if (), while (),
    305 		 * else, etc. up to the start of the following stmt to a buffer. This
    306 		 * allows proper handling of both kinds of brace placement.
    307 		 */
    308 
    309 		flushed_nl = false;
    310 		while (ps.search_brace) {	/* if we scanned an if(),
    311 						 * while(), etc., we might
    312 						 * need to copy stuff into a
    313 						 * buffer we must loop,
    314 						 * copying stuff into
    315 						 * save_com, until we find the
    316 						 * start of the stmt which
    317 						 * follows the if, or whatever */
    318 			switch (type_code) {
    319 			case newline:
    320 				++line_no;
    321 				flushed_nl = true;
    322 			case form_feed:
    323 				break;	/* form feeds and newlines found here
    324 					 * will be ignored */
    325 
    326 			case lbrace:	/* this is a brace that starts the
    327 					 * compound stmt */
    328 				if (sc_end == 0) {	/* ignore buffering if a
    329 							 * comment wasnt stored
    330 							 * up */
    331 					ps.search_brace = false;
    332 					goto check_type;
    333 				}
    334 				if (btype_2) {
    335 					save_com[0] = '{';	/* we either want to put
    336 								 * the brace right after
    337 								 * the if */
    338 					goto sw_buffer;	/* go to common code to
    339 							 * get out of this loop */
    340 				}
    341 			case comment:	/* we have a comment, so we must copy
    342 					 * it into the buffer */
    343 				if (!flushed_nl || sc_end != 0) {
    344 					if (sc_end == 0) {	/* if this is the first
    345 								 * comment, we must set
    346 								 * up the buffer */
    347 						save_com[0] = save_com[1] = ' ';
    348 						sc_end = &(save_com[2]);
    349 					} else {
    350 						*sc_end++ = '\n';	/* add newline between
    351 									 * comments */
    352 						*sc_end++ = ' ';
    353 						--line_no;
    354 					}
    355 					*sc_end++ = '/';	/* copy in start of
    356 								 * comment */
    357 					*sc_end++ = '*';
    358 
    359 					for (;;) {	/* loop until we get to
    360 							 * the end of the
    361 							 * comment */
    362 						*sc_end = *buf_ptr++;
    363 						if (buf_ptr >= buf_end)
    364 							fill_buffer();
    365 
    366 						if (*sc_end++ == '*' && *buf_ptr == '/')
    367 							break;	/* we are at end of
    368 								 * comment */
    369 
    370 						if (sc_end >= &(save_com[sc_size])) {	/* check for temp buffer
    371 											 * overflow */
    372 							diag(1, "Internal buffer overflow - Move big comment from right after if, while, or whatever.");
    373 							fflush(output);
    374 							exit(1);
    375 						}
    376 					}
    377 					*sc_end++ = '/';	/* add ending slash */
    378 					if (++buf_ptr >= buf_end)	/* get past / in buffer */
    379 						fill_buffer();
    380 					break;
    381 				}
    382 			default:	/* it is the start of a normal
    383 					 * statment */
    384 				if (flushed_nl)	/* if we flushed a newline,
    385 						 * make sure it is put back */
    386 					force_nl = true;
    387 				if ((type_code == sp_paren && *token == 'i'
    388 					&& last_else && ps.else_if) ||
    389 				    (type_code == sp_nparen && *token == 'e'
    390 					&& e_code != s_code && e_code[-1] == '}'))
    391 					force_nl = false;
    392 
    393 				if (sc_end == 0) {	/* ignore buffering if
    394 							 * comment wasnt saved
    395 							 * up */
    396 					ps.search_brace = false;
    397 					goto check_type;
    398 				}
    399 				if (force_nl) {	/* if we should insert a nl
    400 						 * here, put it into the
    401 						 * buffer */
    402 					force_nl = false;
    403 					--line_no;	/* this will be
    404 							 * re-increased when the
    405 							 * nl is read from the
    406 							 * buffer */
    407 					*sc_end++ = '\n';
    408 					*sc_end++ = ' ';
    409 					if (verbose && !flushed_nl)	/* print error msg if
    410 									 * the line was not
    411 									 * already broken */
    412 						diag(0, "Line broken");
    413 					flushed_nl = false;
    414 				}
    415 				for (t_ptr = token; *t_ptr; ++t_ptr)
    416 					*sc_end++ = *t_ptr;	/* copy token into temp
    417 								 * buffer */
    418 				ps.procname[0] = 0;
    419 
    420 		sw_buffer:
    421 				ps.search_brace = false;	/* stop looking for
    422 								 * start of stmt */
    423 				bp_save = buf_ptr;	/* save current input
    424 							 * buffer */
    425 				be_save = buf_end;
    426 				buf_ptr = save_com;	/* fix so that
    427 							 * subsequent calls to
    428 							 * lexi will take tokens
    429 							 * out of save_com */
    430 				*sc_end++ = ' ';	/* add trailing blank,
    431 							 * just in case */
    432 				buf_end = sc_end;
    433 				sc_end = 0;
    434 				break;
    435 			}	/* end of switch */
    436 			if (type_code != 0)	/* we must make this check,
    437 						 * just in case there was an
    438 						 * unexpected EOF */
    439 				type_code = lexi();	/* read another token */
    440 			/* if (ps.search_brace) ps.procname[0] = 0; */
    441 			if ((is_procname = ps.procname[0]) && flushed_nl
    442 			    && !procnames_start_line && ps.in_decl
    443 			    && type_code == ident)
    444 				flushed_nl = 0;
    445 		}		/* end of while (search_brace) */
    446 		last_else = 0;
    447 check_type:
    448 		if (type_code == 0) {	/* we got eof */
    449 			if (s_lab != e_lab || s_code != e_code
    450 			    || s_com != e_com)	/* must dump end of line */
    451 				dump_line();
    452 			if (ps.tos > 1)	/* check for balanced braces */
    453 				diag(1, "Stuff missing from end of file.");
    454 
    455 			if (verbose) {
    456 				printf("There were %d output lines and %d comments\n",
    457 				    ps.out_lines, ps.out_coms);
    458 				printf("(Lines with comments)/(Lines with code): %6.3f\n",
    459 				    (1.0 * ps.com_lines) / code_lines);
    460 			}
    461 			fflush(output);
    462 			exit(found_err);
    463 		}
    464 		if (
    465 		    (type_code != comment) &&
    466 		    (type_code != newline) &&
    467 		    (type_code != preesc) &&
    468 		    (type_code != form_feed)) {
    469 			if (force_nl &&
    470 			    (type_code != semicolon) &&
    471 			    (type_code != lbrace || !btype_2)) {
    472 				/* we should force a broken line here */
    473 				if (verbose && !flushed_nl)
    474 					diag(0, "Line broken");
    475 				flushed_nl = false;
    476 				dump_line();
    477 				ps.want_blank = false;	/* dont insert blank at
    478 							 * line start */
    479 				force_nl = false;
    480 			}
    481 			ps.in_stmt = true;	/* turn on flag which causes
    482 						 * an extra level of
    483 						 * indentation. this is turned
    484 						 * off by a ; or '}' */
    485 			if (s_com != e_com) {	/* the turkey has embedded a
    486 						 * comment in a line. fix it */
    487 				*e_code++ = ' ';
    488 				for (t_ptr = s_com; *t_ptr; ++t_ptr) {
    489 					CHECK_SIZE_CODE;
    490 					*e_code++ = *t_ptr;
    491 				}
    492 				*e_code++ = ' ';
    493 				*e_code = '\0';	/* null terminate code sect */
    494 				ps.want_blank = false;
    495 				e_com = s_com;
    496 			}
    497 		} else
    498 			if (type_code != comment)	/* preserve force_nl
    499 							 * thru a comment */
    500 				force_nl = false;	/* cancel forced newline
    501 							 * after newline, form
    502 							 * feed, etc */
    503 
    504 
    505 
    506 		/*-----------------------------------------------------*\
    507 		|	   do switch on type of token scanned		|
    508 		\*-----------------------------------------------------*/
    509 		CHECK_SIZE_CODE;
    510 		switch (type_code) {	/* now, decide what to do with the
    511 					 * token */
    512 
    513 		case form_feed:/* found a form feed in line */
    514 			ps.use_ff = true;	/* a form feed is treated much
    515 						 * like a newline */
    516 			dump_line();
    517 			ps.want_blank = false;
    518 			break;
    519 
    520 		case newline:
    521 			if (ps.last_token != comma || ps.p_l_follow > 0
    522 			    || !ps.leave_comma || ps.block_init || !break_comma || s_com != e_com) {
    523 				dump_line();
    524 				ps.want_blank = false;
    525 			}
    526 			++line_no;	/* keep track of input line number */
    527 			break;
    528 
    529 		case lparen:	/* got a '(' or '[' */
    530 			++ps.p_l_follow;	/* count parens to make Healy
    531 						 * happy */
    532 			if (ps.want_blank && *token != '[' &&
    533 			    (ps.last_token != ident || proc_calls_space
    534 				|| (ps.its_a_keyword && (!ps.sizeof_keyword || Bill_Shannon))))
    535 				*e_code++ = ' ';
    536 			if (ps.in_decl && !ps.block_init) {
    537 				if (troff && !ps.dumped_decl_indent && !is_procname && ps.last_token == decl) {
    538 					ps.dumped_decl_indent = 1;
    539 					sprintf(e_code, "\n.Du %dp+\200p \"%s\"\n", dec_ind * 7, token);
    540 					e_code += strlen(e_code);
    541 				} else {
    542 					while ((e_code - s_code) < dec_ind) {
    543 						CHECK_SIZE_CODE;
    544 						*e_code++ = ' ';
    545 					}
    546 					*e_code++ = token[0];
    547 				}
    548 			} else
    549 				*e_code++ = token[0];
    550 			ps.paren_indents[ps.p_l_follow - 1] = e_code - s_code;
    551 			if (sp_sw && ps.p_l_follow == 1 && extra_expression_indent
    552 			    && ps.paren_indents[0] < 2 * ps.ind_size)
    553 				ps.paren_indents[0] = 2 * ps.ind_size;
    554 			ps.want_blank = false;
    555 			if (ps.in_or_st && *token == '(' && ps.tos <= 2) {
    556 				/*
    557 				 * this is a kluge to make sure that declarations will be
    558 				 * aligned right if proc decl has an explicit type on it, i.e.
    559 				 * "int a(x) {..."
    560 				 */
    561 				parse(semicolon);	/* I said this was a
    562 							 * kluge... */
    563 				ps.in_or_st = false;	/* turn off flag for
    564 							 * structure decl or
    565 							 * initialization */
    566 			}
    567 			if (ps.sizeof_keyword)
    568 				ps.sizeof_mask |= 1 << ps.p_l_follow;
    569 			break;
    570 
    571 		case rparen:	/* got a ')' or ']' */
    572 			rparen_count--;
    573 			if (ps.cast_mask & (1 << ps.p_l_follow) & ~ps.sizeof_mask) {
    574 				ps.last_u_d = true;
    575 				ps.cast_mask &= (1 << ps.p_l_follow) - 1;
    576 			}
    577 			ps.sizeof_mask &= (1 << ps.p_l_follow) - 1;
    578 			if (--ps.p_l_follow < 0) {
    579 				ps.p_l_follow = 0;
    580 				diag(0, "Extra %c", *token);
    581 			}
    582 			if (e_code == s_code)	/* if the paren starts the
    583 						 * line */
    584 				ps.paren_level = ps.p_l_follow;	/* then indent it */
    585 
    586 			*e_code++ = token[0];
    587 			ps.want_blank = true;
    588 
    589 			if (sp_sw && (ps.p_l_follow == 0)) {	/* check for end of if
    590 								 * (...), or some such */
    591 				sp_sw = false;
    592 				force_nl = true;	/* must force newline
    593 							 * after if */
    594 				ps.last_u_d = true;	/* inform lexi that a
    595 							 * following operator is
    596 							 * unary */
    597 				ps.in_stmt = false;	/* dont use stmt
    598 							 * continuation
    599 							 * indentation */
    600 
    601 				parse(hd_type);	/* let parser worry about if,
    602 						 * or whatever */
    603 			}
    604 			ps.search_brace = btype_2;	/* this should insure
    605 							 * that constructs such
    606 							 * as main(){...} and
    607 							 * int[]{...} have their
    608 							 * braces put in the
    609 							 * right place */
    610 			break;
    611 
    612 		case unary_op:	/* this could be any unary operation */
    613 			if (ps.want_blank)
    614 				*e_code++ = ' ';
    615 
    616 			if (troff && !ps.dumped_decl_indent && ps.in_decl && !is_procname) {
    617 				sprintf(e_code, "\n.Du %dp+\200p \"%s\"\n", dec_ind * 7, token);
    618 				ps.dumped_decl_indent = 1;
    619 				e_code += strlen(e_code);
    620 			} else {
    621 				char   *res = token;
    622 
    623 				if (ps.in_decl && !ps.block_init) {	/* if this is a unary op
    624 									 * in a declaration, we
    625 									 * should indent this
    626 									 * token */
    627 					for (i = 0; token[i]; ++i);	/* find length of token */
    628 					while ((e_code - s_code) < (dec_ind - i)) {
    629 						CHECK_SIZE_CODE;
    630 						*e_code++ = ' ';	/* pad it */
    631 					}
    632 				}
    633 				if (troff && token[0] == '-' && token[1] == '>')
    634 					res = "\\(->";
    635 				for (t_ptr = res; *t_ptr; ++t_ptr) {
    636 					CHECK_SIZE_CODE;
    637 					*e_code++ = *t_ptr;
    638 				}
    639 			}
    640 			ps.want_blank = false;
    641 			break;
    642 
    643 		case binary_op:/* any binary operation */
    644 			if (ps.want_blank)
    645 				*e_code++ = ' ';
    646 			{
    647 				char   *res = token;
    648 
    649 				if (troff)
    650 					switch (token[0]) {
    651 					case '<':
    652 						if (token[1] == '=')
    653 							res = "\\(<=";
    654 						break;
    655 					case '>':
    656 						if (token[1] == '=')
    657 							res = "\\(>=";
    658 						break;
    659 					case '!':
    660 						if (token[1] == '=')
    661 							res = "\\(!=";
    662 						break;
    663 					case '|':
    664 						if (token[1] == '|')
    665 							res = "\\(br\\(br";
    666 						else
    667 							if (token[1] == 0)
    668 								res = "\\(br";
    669 						break;
    670 					}
    671 				for (t_ptr = res; *t_ptr; ++t_ptr) {
    672 					CHECK_SIZE_CODE;
    673 					*e_code++ = *t_ptr;	/* move the operator */
    674 				}
    675 			}
    676 			ps.want_blank = true;
    677 			break;
    678 
    679 		case postop:	/* got a trailing ++ or -- */
    680 			*e_code++ = token[0];
    681 			*e_code++ = token[1];
    682 			ps.want_blank = true;
    683 			break;
    684 
    685 		case question:	/* got a ? */
    686 			squest++;	/* this will be used when a later
    687 					 * colon appears so we can distinguish
    688 					 * the <c>?<n>:<n> construct */
    689 			if (ps.want_blank)
    690 				*e_code++ = ' ';
    691 			*e_code++ = '?';
    692 			ps.want_blank = true;
    693 			break;
    694 
    695 		case casestmt:	/* got word 'case' or 'default' */
    696 			scase = true;	/* so we can process the later colon
    697 					 * properly */
    698 			goto copy_id;
    699 
    700 		case colon:	/* got a ':' */
    701 			if (squest > 0) {	/* it is part of the <c>?<n>:
    702 						 * <n> construct */
    703 				--squest;
    704 				if (ps.want_blank)
    705 					*e_code++ = ' ';
    706 				*e_code++ = ':';
    707 				ps.want_blank = true;
    708 				break;
    709 			}
    710 			if (ps.in_or_st) {
    711 				*e_code++ = ':';
    712 				ps.want_blank = false;
    713 				break;
    714 			}
    715 			ps.in_stmt = false;	/* seeing a label does not
    716 						 * imply we are in a stmt */
    717 			for (t_ptr = s_code; *t_ptr; ++t_ptr)
    718 				*e_lab++ = *t_ptr;	/* turn everything so
    719 							 * far into a label */
    720 			e_code = s_code;
    721 			*e_lab++ = ':';
    722 			*e_lab++ = ' ';
    723 			*e_lab = '\0';
    724 
    725 			force_nl = ps.pcase = scase;	/* ps.pcase will be used
    726 							 * by dump_line to
    727 							 * decide how to indent
    728 							 * the label. force_nl
    729 							 * will force a case n:
    730 							 * to be on a line by
    731 							 * itself */
    732 			scase = false;
    733 			ps.want_blank = false;
    734 			break;
    735 
    736 		case semicolon:/* got a ';' */
    737 			ps.in_or_st = false;	/* we are not in an
    738 						 * initialization or structure
    739 						 * declaration */
    740 			scase = false;	/* these will only need resetting in a
    741 					 * error */
    742 			squest = 0;
    743 			if (ps.last_token == rparen && rparen_count == 0)
    744 				ps.in_parameter_declaration = 0;
    745 			ps.cast_mask = 0;
    746 			ps.sizeof_mask = 0;
    747 			ps.block_init = 0;
    748 			ps.block_init_level = 0;
    749 			ps.just_saw_decl--;
    750 
    751 			if (ps.in_decl && s_code == e_code && !ps.block_init)
    752 				while ((e_code - s_code) < (dec_ind - 1)) {
    753 					CHECK_SIZE_CODE;
    754 					*e_code++ = ' ';
    755 				}
    756 
    757 			ps.in_decl = (ps.dec_nest > 0);	/* if we were in a first
    758 							 * level structure
    759 							 * declaration, we arent
    760 							 * any more */
    761 
    762 			if ((!sp_sw || hd_type != forstmt) && ps.p_l_follow > 0) {
    763 
    764 				/*
    765 				 * This should be true iff there were unbalanced parens in the
    766 				 * stmt.  It is a bit complicated, because the semicolon might
    767 				 * be in a for stmt
    768 				 */
    769 				diag(1, "Unbalanced parens");
    770 				ps.p_l_follow = 0;
    771 				if (sp_sw) {	/* this is a check for a if,
    772 						 * while, etc. with unbalanced
    773 						 * parens */
    774 					sp_sw = false;
    775 					parse(hd_type);	/* dont lose the if, or
    776 							 * whatever */
    777 				}
    778 			}
    779 			*e_code++ = ';';
    780 			ps.want_blank = true;
    781 			ps.in_stmt = (ps.p_l_follow > 0);	/* we are no longer in
    782 								 * the middle of a stmt */
    783 
    784 			if (!sp_sw) {	/* if not if for (;;) */
    785 				parse(semicolon);	/* let parser know about
    786 							 * end of stmt */
    787 				force_nl = true;	/* force newline after a
    788 							 * end of stmt */
    789 			}
    790 			break;
    791 
    792 		case lbrace:	/* got a '{' */
    793 			ps.in_stmt = false;	/* dont indent the {} */
    794 			if (!ps.block_init)
    795 				force_nl = true;	/* force other stuff on
    796 							 * same line as '{' onto
    797 							 * new line */
    798 			else
    799 				if (ps.block_init_level <= 0)
    800 					ps.block_init_level = 1;
    801 				else
    802 					ps.block_init_level++;
    803 
    804 			if (s_code != e_code && !ps.block_init) {
    805 				if (!btype_2) {
    806 					dump_line();
    807 					ps.want_blank = false;
    808 				} else
    809 					if (ps.in_parameter_declaration && !ps.in_or_st) {
    810 						ps.i_l_follow = 0;
    811 						dump_line();
    812 						ps.want_blank = false;
    813 					}
    814 			}
    815 			if (ps.in_parameter_declaration)
    816 				prefix_blankline_requested = 0;
    817 
    818 			if (ps.p_l_follow > 0) {	/* check for preceding
    819 							 * unbalanced parens */
    820 				diag(1, "Unbalanced parens");
    821 				ps.p_l_follow = 0;
    822 				if (sp_sw) {	/* check for unclosed if, for,
    823 						 * etc. */
    824 					sp_sw = false;
    825 					parse(hd_type);
    826 					ps.ind_level = ps.i_l_follow;
    827 				}
    828 			}
    829 			if (s_code == e_code)
    830 				ps.ind_stmt = false;	/* dont put extra
    831 							 * indentation on line
    832 							 * with '{' */
    833 			if (ps.in_decl && ps.in_or_st) {	/* this is either a
    834 								 * structure declaration
    835 								 * or an init */
    836 				di_stack[ps.dec_nest++] = dec_ind;
    837 				/* ?		dec_ind = 0; */
    838 			} else {
    839 				ps.decl_on_line = false;	/* we cant be in the
    840 								 * middle of a
    841 								 * declaration, so dont
    842 								 * do special
    843 								 * indentation of
    844 								 * comments */
    845 				if (blanklines_after_declarations_at_proctop
    846 				    && ps.in_parameter_declaration)
    847 					postfix_blankline_requested = 1;
    848 				ps.in_parameter_declaration = 0;
    849 			}
    850 			dec_ind = 0;
    851 			parse(lbrace);	/* let parser know about this */
    852 			if (ps.want_blank)	/* put a blank before '{' if
    853 						 * '{' is not at start of line */
    854 				*e_code++ = ' ';
    855 			ps.want_blank = false;
    856 			*e_code++ = '{';
    857 			ps.just_saw_decl = 0;
    858 			break;
    859 
    860 		case rbrace:	/* got a '}' */
    861 			if (ps.p_stack[ps.tos] == decl && !ps.block_init)	/* semicolons can be
    862 										 * omitted in
    863 										 * declarations */
    864 				parse(semicolon);
    865 			if (ps.p_l_follow) {	/* check for unclosed if, for,
    866 						 * else. */
    867 				diag(1, "Unbalanced parens");
    868 				ps.p_l_follow = 0;
    869 				sp_sw = false;
    870 			}
    871 			ps.just_saw_decl = 0;
    872 			ps.block_init_level--;
    873 			if (s_code != e_code && !ps.block_init) {	/* '}' must be first on
    874 									 * line */
    875 				if (verbose)
    876 					diag(0, "Line broken");
    877 				dump_line();
    878 			}
    879 			*e_code++ = '}';
    880 			ps.want_blank = true;
    881 			ps.in_stmt = ps.ind_stmt = false;
    882 			if (ps.dec_nest > 0) {	/* we are in multi-level
    883 						 * structure declaration */
    884 				dec_ind = di_stack[--ps.dec_nest];
    885 				if (ps.dec_nest == 0 && !ps.in_parameter_declaration)
    886 					ps.just_saw_decl = 2;
    887 				ps.in_decl = true;
    888 			}
    889 			prefix_blankline_requested = 0;
    890 			parse(rbrace);	/* let parser know about this */
    891 			ps.search_brace = cuddle_else && ps.p_stack[ps.tos] == ifhead
    892 			    && ps.il[ps.tos] >= ps.ind_level;
    893 			if (ps.tos <= 1 && blanklines_after_procs && ps.dec_nest <= 0)
    894 				postfix_blankline_requested = 1;
    895 			break;
    896 
    897 		case swstmt:	/* got keyword "switch" */
    898 			sp_sw = true;
    899 			hd_type = swstmt;	/* keep this for when we have
    900 						 * seen the expression */
    901 			goto copy_id;	/* go move the token into buffer */
    902 
    903 		case sp_paren:	/* token is if, while, for */
    904 			sp_sw = true;	/* the interesting stuff is done after
    905 					 * the expression is scanned */
    906 			hd_type = (*token == 'i' ? ifstmt :
    907 			    (*token == 'w' ? whilestmt : forstmt));
    908 
    909 			/*
    910 		         * remember the type of header for later use by parser
    911 		         */
    912 			goto copy_id;	/* copy the token into line */
    913 
    914 		case sp_nparen:/* got else, do */
    915 			ps.in_stmt = false;
    916 			if (*token == 'e') {
    917 				if (e_code != s_code && (!cuddle_else || e_code[-1] != '}')) {
    918 					if (verbose)
    919 						diag(0, "Line broken");
    920 					dump_line();	/* make sure this starts
    921 							 * a line */
    922 					ps.want_blank = false;
    923 				}
    924 				force_nl = true;	/* also, following stuff
    925 							 * must go onto new line */
    926 				last_else = 1;
    927 				parse(elselit);
    928 			} else {
    929 				if (e_code != s_code) {	/* make sure this starts
    930 							 * a line */
    931 					if (verbose)
    932 						diag(0, "Line broken");
    933 					dump_line();
    934 					ps.want_blank = false;
    935 				}
    936 				force_nl = true;	/* also, following stuff
    937 							 * must go onto new line */
    938 				last_else = 0;
    939 				parse(dolit);
    940 			}
    941 			goto copy_id;	/* move the token into line */
    942 
    943 		case decl:	/* we have a declaration type (int, register,
    944 				 * etc.) */
    945 			parse(decl);	/* let parser worry about indentation */
    946 			if (ps.last_token == rparen && ps.tos <= 1) {
    947 				ps.in_parameter_declaration = 1;
    948 				if (s_code != e_code) {
    949 					dump_line();
    950 					ps.want_blank = 0;
    951 				}
    952 			}
    953 			if (ps.in_parameter_declaration && ps.indent_parameters && ps.dec_nest == 0) {
    954 				ps.ind_level = ps.i_l_follow = 1;
    955 				ps.ind_stmt = 0;
    956 			}
    957 			ps.in_or_st = true;	/* this might be a structure
    958 						 * or initialization
    959 						 * declaration */
    960 			ps.in_decl = ps.decl_on_line = true;
    961 			if ( /* !ps.in_or_st && */ ps.dec_nest <= 0)
    962 				ps.just_saw_decl = 2;
    963 			prefix_blankline_requested = 0;
    964 			for (i = 0; token[i++];);	/* get length of token */
    965 
    966 			/*
    967 		         * dec_ind = e_code - s_code + (ps.decl_indent>i ? ps.decl_indent
    968 		         * : i);
    969 		         */
    970 			dec_ind = ps.decl_indent > 0 ? ps.decl_indent : i;
    971 			goto copy_id;
    972 
    973 		case ident:	/* got an identifier or constant */
    974 			if (ps.in_decl) {	/* if we are in a declaration,
    975 						 * we must indent identifier */
    976 				if (ps.want_blank)
    977 					*e_code++ = ' ';
    978 				ps.want_blank = false;
    979 				if (is_procname == 0 || !procnames_start_line) {
    980 					if (!ps.block_init) {
    981 						if (troff && !ps.dumped_decl_indent) {
    982 							sprintf(e_code, "\n.De %dp+\200p\n", dec_ind * 7);
    983 							ps.dumped_decl_indent = 1;
    984 							e_code += strlen(e_code);
    985 						} else
    986 							while ((e_code - s_code) < dec_ind) {
    987 								CHECK_SIZE_CODE;
    988 								*e_code++ = ' ';
    989 							}
    990 					}
    991 				} else {
    992 					if (dec_ind && s_code != e_code)
    993 						dump_line();
    994 					dec_ind = 0;
    995 					ps.want_blank = false;
    996 				}
    997 			} else
    998 				if (sp_sw && ps.p_l_follow == 0) {
    999 					sp_sw = false;
   1000 					force_nl = true;
   1001 					ps.last_u_d = true;
   1002 					ps.in_stmt = false;
   1003 					parse(hd_type);
   1004 				}
   1005 	copy_id:
   1006 			if (ps.want_blank)
   1007 				*e_code++ = ' ';
   1008 			if (troff && ps.its_a_keyword) {
   1009 				e_code = chfont(&bodyf, &keywordf, e_code);
   1010 				for (t_ptr = token; *t_ptr; ++t_ptr) {
   1011 					CHECK_SIZE_CODE;
   1012 					*e_code++ = keywordf.allcaps && islower((unsigned char)*t_ptr)
   1013 					    ? toupper(*t_ptr) : *t_ptr;
   1014 				}
   1015 				e_code = chfont(&keywordf, &bodyf, e_code);
   1016 			} else
   1017 				for (t_ptr = token; *t_ptr; ++t_ptr) {
   1018 					CHECK_SIZE_CODE;
   1019 					*e_code++ = *t_ptr;
   1020 				}
   1021 			ps.want_blank = true;
   1022 			break;
   1023 
   1024 		case period:	/* treat a period kind of like a binary
   1025 				 * operation */
   1026 			*e_code++ = '.';	/* move the period into line */
   1027 			ps.want_blank = false;	/* dont put a blank after a
   1028 						 * period */
   1029 			break;
   1030 
   1031 		case comma:
   1032 			ps.want_blank = (s_code != e_code);	/* only put blank after
   1033 								 * comma if comma does
   1034 								 * not start the line */
   1035 			if (ps.in_decl && is_procname == 0 && !ps.block_init)
   1036 				while ((e_code - s_code) < (dec_ind - 1)) {
   1037 					CHECK_SIZE_CODE;
   1038 					*e_code++ = ' ';
   1039 				}
   1040 
   1041 			*e_code++ = ',';
   1042 			if (ps.p_l_follow == 0) {
   1043 				if (ps.block_init_level <= 0)
   1044 					ps.block_init = 0;
   1045 				if (break_comma && (!ps.leave_comma || compute_code_target() + (e_code - s_code) > max_col - 8))
   1046 					force_nl = true;
   1047 			}
   1048 			break;
   1049 
   1050 		case preesc:	/* got the character '#' */
   1051 			if ((s_com != e_com) ||
   1052 			    (s_lab != e_lab) ||
   1053 			    (s_code != e_code))
   1054 				dump_line();
   1055 			*e_lab++ = '#';	/* move whole line to 'label' buffer */
   1056 			{
   1057 				int     in_comment = 0;
   1058 				int     com_start = 0;
   1059 				char    quote = 0;
   1060 				int     com_end = 0;
   1061 
   1062 				while (*buf_ptr == ' ' || *buf_ptr == '\t') {
   1063 					buf_ptr++;
   1064 					if (buf_ptr >= buf_end)
   1065 						fill_buffer();
   1066 				}
   1067 				while (*buf_ptr != '\n' || in_comment) {
   1068 					CHECK_SIZE_LAB;
   1069 					*e_lab = *buf_ptr++;
   1070 					if (buf_ptr >= buf_end)
   1071 						fill_buffer();
   1072 					switch (*e_lab++) {
   1073 					case BACKSLASH:
   1074 						if (troff)
   1075 							*e_lab++ = BACKSLASH;
   1076 						if (!in_comment) {
   1077 							*e_lab++ = *buf_ptr++;
   1078 							if (buf_ptr >= buf_end)
   1079 								fill_buffer();
   1080 						}
   1081 						break;
   1082 					case '/':
   1083 						if (*buf_ptr == '*' && !in_comment && !quote) {
   1084 							in_comment = 1;
   1085 							*e_lab++ = *buf_ptr++;
   1086 							com_start = e_lab - s_lab - 2;
   1087 						}
   1088 						break;
   1089 					case '"':
   1090 						if (quote == '"')
   1091 							quote = 0;
   1092 						break;
   1093 					case '\'':
   1094 						if (quote == '\'')
   1095 							quote = 0;
   1096 						break;
   1097 					case '*':
   1098 						if (*buf_ptr == '/' && in_comment) {
   1099 							in_comment = 0;
   1100 							*e_lab++ = *buf_ptr++;
   1101 							com_end = e_lab - s_lab;
   1102 						}
   1103 						break;
   1104 					}
   1105 				}
   1106 
   1107 				while (e_lab > s_lab && (e_lab[-1] == ' ' || e_lab[-1] == '\t'))
   1108 					e_lab--;
   1109 				if (e_lab - s_lab == com_end && bp_save == 0) {	/* comment on
   1110 										 * preprocessor line */
   1111 					if (sc_end == 0)	/* if this is the first
   1112 								 * comment, we must set
   1113 								 * up the buffer */
   1114 						sc_end = &(save_com[0]);
   1115 					else {
   1116 						*sc_end++ = '\n';	/* add newline between
   1117 									 * comments */
   1118 						*sc_end++ = ' ';
   1119 						--line_no;
   1120 					}
   1121 					memmove(sc_end, s_lab + com_start, com_end - com_start);
   1122 					sc_end += com_end - com_start;
   1123 					if (sc_end >= &save_com[sc_size])
   1124 						abort();
   1125 					e_lab = s_lab + com_start;
   1126 					while (e_lab > s_lab && (e_lab[-1] == ' ' || e_lab[-1] == '\t'))
   1127 						e_lab--;
   1128 					bp_save = buf_ptr;	/* save current input
   1129 								 * buffer */
   1130 					be_save = buf_end;
   1131 					buf_ptr = save_com;	/* fix so that
   1132 								 * subsequent calls to
   1133 								 * lexi will take tokens
   1134 								 * out of save_com */
   1135 					*sc_end++ = ' ';	/* add trailing blank,
   1136 								 * just in case */
   1137 					buf_end = sc_end;
   1138 					sc_end = 0;
   1139 				}
   1140 				*e_lab = '\0';	/* null terminate line */
   1141 				ps.pcase = false;
   1142 			}
   1143 
   1144 			if (strncmp(s_lab, "#if", 3) == 0) {
   1145 				if (blanklines_around_conditional_compilation) {
   1146 					int     c;
   1147 					prefix_blankline_requested++;
   1148 					while ((c = getc(input)) == '\n');
   1149 					ungetc(c, input);
   1150 				}
   1151 				if (ifdef_level < sizeof state_stack / sizeof state_stack[0]) {
   1152 					match_state[ifdef_level].tos = -1;
   1153 					state_stack[ifdef_level++] = ps;
   1154 				} else
   1155 					diag(1, "#if stack overflow");
   1156 			} else
   1157 				if (strncmp(s_lab, "#else", 5) == 0) {
   1158 					if (ifdef_level <= 0)
   1159 						diag(1, "Unmatched #else");
   1160 					else {
   1161 						match_state[ifdef_level - 1] = ps;
   1162 						ps = state_stack[ifdef_level - 1];
   1163 					}
   1164 				} else
   1165 					if (strncmp(s_lab, "#endif", 6) == 0) {
   1166 						if (ifdef_level <= 0)
   1167 							diag(1, "Unmatched #endif");
   1168 						else {
   1169 							ifdef_level--;
   1170 
   1171 #ifdef undef
   1172 							/*
   1173 						         * This match needs to be more intelligent before the
   1174 						         * message is useful
   1175 						         */
   1176 							if (match_state[ifdef_level].tos >= 0
   1177 							    && memcmp(&ps, &match_state[ifdef_level], sizeof ps))
   1178 								diag(0, "Syntactically inconsistant #ifdef alternatives.");
   1179 #endif
   1180 						}
   1181 						if (blanklines_around_conditional_compilation) {
   1182 							postfix_blankline_requested++;
   1183 							n_real_blanklines = 0;
   1184 						}
   1185 					}
   1186 			break;	/* subsequent processing of the newline
   1187 				 * character will cause the line to be printed */
   1188 
   1189 		case comment:	/* we have gotten a start comment */
   1190 			/* this is a biggie */
   1191 			if (flushed_nl) {	/* we should force a broken
   1192 						 * line here */
   1193 				flushed_nl = false;
   1194 				dump_line();
   1195 				ps.want_blank = false;	/* dont insert blank at
   1196 							 * line start */
   1197 				force_nl = false;
   1198 			}
   1199 			pr_comment();
   1200 			break;
   1201 		}		/* end of big switch stmt */
   1202 
   1203 		*e_code = '\0';	/* make sure code section is null terminated */
   1204 		if (type_code != comment && type_code != newline && type_code != preesc)
   1205 			ps.last_token = type_code;
   1206 	}			/* end of main while (1) loop */
   1207 }
   1208 /*
   1209  * copy input file to backup file if in_name is /blah/blah/blah/file, then
   1210  * backup file will be ".Bfile" then make the backup file the input and
   1211  * original input file the output
   1212  */
   1213 void
   1214 bakcopy(void)
   1215 {
   1216 	int     n, bakchn;
   1217 	char    buff[8 * 1024];
   1218 	char   *p;
   1219 
   1220 	/* construct file name .Bfile */
   1221 	for (p = in_name; *p; p++);	/* skip to end of string */
   1222 	while (p > in_name && *p != '/')	/* find last '/' */
   1223 		p--;
   1224 	if (*p == '/')
   1225 		p++;
   1226 	sprintf(bakfile, "%s.BAK", p);
   1227 
   1228 	/* copy in_name to backup file */
   1229 	bakchn = creat(bakfile, 0600);
   1230 	if (bakchn < 0)
   1231 		err(1, "%s", bakfile);
   1232 	while ((n = read(fileno(input), buff, sizeof buff)) > 0)
   1233 		if (write(bakchn, buff, n) != n)
   1234 			err(1, "%s", bakfile);
   1235 	if (n < 0)
   1236 		err(1, "%s", in_name);
   1237 	close(bakchn);
   1238 	fclose(input);
   1239 
   1240 	/* re-open backup file as the input file */
   1241 	input = fopen(bakfile, "r");
   1242 	if (input == 0)
   1243 		err(1, "%s", bakfile);
   1244 	/* now the original input file will be the output */
   1245 	output = fopen(in_name, "w");
   1246 	if (output == 0) {
   1247 		unlink(bakfile);
   1248 		err(1, "%s", in_name);
   1249 	}
   1250 }
   1251