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indent.c revision 1.10
      1 /*	$NetBSD: indent.c,v 1.10 1998/12/19 17:00:08 christos 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 1.10 1998/12/19 17:00:08 christos 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 __P((int, char **));
     76 
     77 int
     78 main(argc, argv)
     79 	int     argc;
     80 	char  **argv;
     81 {
     82 
     83 	extern int found_err;	/* flag set in diag() on error */
     84 	int     dec_ind;	/* current indentation for declarations */
     85 	int     di_stack[20];	/* a stack of structure indentation levels */
     86 	int     flushed_nl;	/* used when buffering up comments to remember
     87 				 * that a newline was passed over */
     88 	int     force_nl;	/* when true, code must be broken */
     89 	int     hd_type;	/* used to store type of stmt for if (...),
     90 				 * for (...), etc */
     91 	int     i;		/* local loop counter */
     92 	int     scase;		/* set to true when we see a case, so we will
     93 				 * know what to do with the following colon */
     94 	int     sp_sw;		/* when true, we are in the expressin of
     95 				 * if(...), while(...), etc. */
     96 	int     squest;		/* when this is positive, we have seen a ?
     97 				 * without the matching : in a <c>?<s>:<s>
     98 				 * construct */
     99 	char   *t_ptr;		/* used for copying tokens */
    100 	int     type_code;	/* the type of token, returned by lexi */
    101 
    102 	int     last_else = 0;	/* true iff last keyword was an else */
    103 
    104 
    105 	/*-----------------------------------------------*\
    106         |		      INITIALIZATION		      |
    107         \*-----------------------------------------------*/
    108 
    109 
    110 	hd_type = 0;
    111 	ps.p_stack[0] = stmt;	/* this is the parser's stack */
    112 	ps.last_nl = true;	/* this is true if the last thing scanned was
    113 				 * a newline */
    114 	ps.last_token = semicolon;
    115 	combuf = (char *) malloc(bufsize);
    116 	labbuf = (char *) malloc(bufsize);
    117 	codebuf = (char *) malloc(bufsize);
    118 	tokenbuf = (char *) malloc(bufsize);
    119 	l_com = combuf + bufsize - 5;
    120 	l_lab = labbuf + bufsize - 5;
    121 	l_code = codebuf + bufsize - 5;
    122 	l_token = tokenbuf + bufsize - 5;
    123 	combuf[0] = codebuf[0] = labbuf[0] = ' ';	/* set up code, label,
    124 							 * and comment buffers */
    125 	combuf[1] = codebuf[1] = labbuf[1] = '\0';
    126 	ps.else_if = 1;		/* Default else-if special processing to on */
    127 	s_lab = e_lab = labbuf + 1;
    128 	s_code = e_code = codebuf + 1;
    129 	s_com = e_com = combuf + 1;
    130 	s_token = e_token = tokenbuf + 1;
    131 
    132 	in_buffer = (char *) malloc(10);
    133 	in_buffer_limit = in_buffer + 8;
    134 	buf_ptr = buf_end = in_buffer;
    135 	line_no = 1;
    136 	had_eof = ps.in_decl = ps.decl_on_line = break_comma = false;
    137 	sp_sw = force_nl = false;
    138 	ps.in_or_st = false;
    139 	ps.bl_line = true;
    140 	dec_ind = 0;
    141 	di_stack[ps.dec_nest = 0] = 0;
    142 	ps.want_blank = ps.in_stmt = ps.ind_stmt = false;
    143 
    144 
    145 	scase = ps.pcase = false;
    146 	squest = 0;
    147 	sc_end = 0;
    148 	bp_save = 0;
    149 	be_save = 0;
    150 
    151 	output = 0;
    152 
    153 
    154 
    155 	/*--------------------------------------------------*\
    156         |   		COMMAND LINE SCAN		 |
    157         \*--------------------------------------------------*/
    158 
    159 #ifdef undef
    160 	max_col = 78;		/* -l78 */
    161 	lineup_to_parens = 1;	/* -lp */
    162 	ps.ljust_decl = 0;	/* -ndj */
    163 	ps.com_ind = 33;	/* -c33 */
    164 	star_comment_cont = 1;	/* -sc */
    165 	ps.ind_size = 8;	/* -i8 */
    166 	verbose = 0;
    167 	ps.decl_indent = 16;	/* -di16 */
    168 	ps.indent_parameters = 1;	/* -ip */
    169 	ps.decl_com_ind = 0;	/* if this is not set to some positive value
    170 				 * by an arg, we will set this equal to
    171 				 * ps.com_ind */
    172 	btype_2 = 1;		/* -br */
    173 	cuddle_else = 1;	/* -ce */
    174 	ps.unindent_displace = 0;	/* -d0 */
    175 	ps.case_indent = 0;	/* -cli0 */
    176 	format_col1_comments = 1;	/* -fc1 */
    177 	procnames_start_line = 1;	/* -psl */
    178 	proc_calls_space = 0;	/* -npcs */
    179 	comment_delimiter_on_blankline = 1;	/* -cdb */
    180 	ps.leave_comma = 1;	/* -nbc */
    181 #endif
    182 
    183 	for (i = 1; i < argc; ++i)
    184 		if (strcmp(argv[i], "-npro") == 0)
    185 			break;
    186 	set_defaults();
    187 	if (i >= argc)
    188 		set_profile();
    189 
    190 	for (i = 1; i < argc; ++i) {
    191 
    192 		/*
    193 		 * look thru args (if any) for changes to defaults
    194 		 */
    195 		if (argv[i][0] != '-') {	/* no flag on parameter */
    196 			if (input == 0) {	/* we must have the input file */
    197 				in_name = argv[i];	/* remember name of
    198 							 * input file */
    199 				input = fopen(in_name, "r");
    200 				if (input == 0)	/* check for open error */
    201 					err(1, "%s", in_name);
    202 				continue;
    203 			} else
    204 				if (output == 0) {	/* we have the output
    205 							 * file */
    206 					out_name = argv[i];	/* remember name of
    207 								 * output file */
    208 					if (strcmp(in_name, out_name) == 0) {	/* attempt to overwrite
    209 										 * the file */
    210 						fprintf(stderr, "indent: input and output files must be different\n");
    211 						exit(1);
    212 					}
    213 					output = fopen(out_name, "w");
    214 					if (output == 0)	/* check for create
    215 								 * error */
    216 						err(1, "%s", out_name);
    217 					continue;
    218 				}
    219 			fprintf(stderr, "indent: unknown parameter: %s\n", argv[i]);
    220 			exit(1);
    221 		} else
    222 			set_option(argv[i]);
    223 	}			/* end of for */
    224 	if (input == 0) {
    225 		input = stdin;
    226 	}
    227 	if (output == 0) {
    228 		if (troff || input == stdin)
    229 			output = stdout;
    230 		else {
    231 			out_name = in_name;
    232 			bakcopy();
    233 		}
    234 	}
    235 	if (ps.com_ind <= 1)
    236 		ps.com_ind = 2;	/* dont put normal comments before column 2 */
    237 	if (troff) {
    238 		if (bodyf.font[0] == 0)
    239 			parsefont(&bodyf, "R");
    240 		if (scomf.font[0] == 0)
    241 			parsefont(&scomf, "I");
    242 		if (blkcomf.font[0] == 0)
    243 			blkcomf = scomf, blkcomf.size += 2;
    244 		if (boxcomf.font[0] == 0)
    245 			boxcomf = blkcomf;
    246 		if (stringf.font[0] == 0)
    247 			parsefont(&stringf, "L");
    248 		if (keywordf.font[0] == 0)
    249 			parsefont(&keywordf, "B");
    250 		writefdef(&bodyf, 'B');
    251 		writefdef(&scomf, 'C');
    252 		writefdef(&blkcomf, 'L');
    253 		writefdef(&boxcomf, 'X');
    254 		writefdef(&stringf, 'S');
    255 		writefdef(&keywordf, 'K');
    256 	}
    257 	if (block_comment_max_col <= 0)
    258 		block_comment_max_col = max_col;
    259 	if (ps.decl_com_ind <= 0)	/* if not specified by user, set this */
    260 		ps.decl_com_ind = ps.ljust_decl ? (ps.com_ind <= 10 ? 2 : ps.com_ind - 8) : ps.com_ind;
    261 	if (continuation_indent == 0)
    262 		continuation_indent = ps.ind_size;
    263 	fill_buffer();		/* get first batch of stuff into input buffer */
    264 
    265 	parse(semicolon);
    266 	{
    267 		char   *p = buf_ptr;
    268 		int     col = 1;
    269 
    270 		while (1) {
    271 			if (*p == ' ')
    272 				col++;
    273 			else
    274 				if (*p == '\t')
    275 					col = ((col - 1) & ~7) + 9;
    276 				else
    277 					break;
    278 			p++;
    279 		}
    280 		if (col > ps.ind_size)
    281 			ps.ind_level = ps.i_l_follow = col / ps.ind_size;
    282 	}
    283 	if (troff) {
    284 		char   *p = in_name, *beg = in_name;
    285 
    286 		while (*p)
    287 			if (*p++ == '/')
    288 				beg = p;
    289 		fprintf(output, ".Fn \"%s\"\n", beg);
    290 	}
    291 	/*
    292          * START OF MAIN LOOP
    293          */
    294 
    295 	while (1) {		/* this is the main loop.  it will go until we
    296 				 * reach eof */
    297 		int     is_procname;
    298 
    299 		type_code = lexi();	/* lexi reads one token.  The actual
    300 					 * characters read are stored in
    301 					 * "token". lexi returns a code
    302 					 * indicating the type of token */
    303 		is_procname = ps.procname[0];
    304 
    305 		/*
    306 		 * The following code moves everything following an if (), while (),
    307 		 * else, etc. up to the start of the following stmt to a buffer. This
    308 		 * allows proper handling of both kinds of brace placement.
    309 		 */
    310 
    311 		flushed_nl = false;
    312 		while (ps.search_brace) {	/* if we scanned an if(),
    313 						 * while(), etc., we might
    314 						 * need to copy stuff into a
    315 						 * buffer we must loop,
    316 						 * copying stuff into
    317 						 * save_com, until we find the
    318 						 * start of the stmt which
    319 						 * follows the if, or whatever */
    320 			switch (type_code) {
    321 			case newline:
    322 				++line_no;
    323 				flushed_nl = true;
    324 			case form_feed:
    325 				break;	/* form feeds and newlines found here
    326 					 * will be ignored */
    327 
    328 			case lbrace:	/* this is a brace that starts the
    329 					 * compound stmt */
    330 				if (sc_end == 0) {	/* ignore buffering if a
    331 							 * comment wasnt stored
    332 							 * up */
    333 					ps.search_brace = false;
    334 					goto check_type;
    335 				}
    336 				if (btype_2) {
    337 					save_com[0] = '{';	/* we either want to put
    338 								 * the brace right after
    339 								 * the if */
    340 					goto sw_buffer;	/* go to common code to
    341 							 * get out of this loop */
    342 				}
    343 			case comment:	/* we have a comment, so we must copy
    344 					 * it into the buffer */
    345 				if (!flushed_nl || sc_end != 0) {
    346 					if (sc_end == 0) {	/* if this is the first
    347 								 * comment, we must set
    348 								 * up the buffer */
    349 						save_com[0] = save_com[1] = ' ';
    350 						sc_end = &(save_com[2]);
    351 					} else {
    352 						*sc_end++ = '\n';	/* add newline between
    353 									 * comments */
    354 						*sc_end++ = ' ';
    355 						--line_no;
    356 					}
    357 					*sc_end++ = '/';	/* copy in start of
    358 								 * comment */
    359 					*sc_end++ = '*';
    360 
    361 					for (;;) {	/* loop until we get to
    362 							 * the end of the
    363 							 * comment */
    364 						*sc_end = *buf_ptr++;
    365 						if (buf_ptr >= buf_end)
    366 							fill_buffer();
    367 
    368 						if (*sc_end++ == '*' && *buf_ptr == '/')
    369 							break;	/* we are at end of
    370 								 * comment */
    371 
    372 						if (sc_end >= &(save_com[sc_size])) {	/* check for temp buffer
    373 											 * overflow */
    374 							diag(1, "Internal buffer overflow - Move big comment from right after if, while, or whatever.");
    375 							fflush(output);
    376 							exit(1);
    377 						}
    378 					}
    379 					*sc_end++ = '/';	/* add ending slash */
    380 					if (++buf_ptr >= buf_end)	/* get past / in buffer */
    381 						fill_buffer();
    382 					break;
    383 				}
    384 			default:	/* it is the start of a normal
    385 					 * statment */
    386 				if (flushed_nl)	/* if we flushed a newline,
    387 						 * make sure it is put back */
    388 					force_nl = true;
    389 				if ((type_code == sp_paren && *token == 'i'
    390 					&& last_else && ps.else_if) ||
    391 				    (type_code == sp_nparen && *token == 'e'
    392 					&& e_code != s_code && e_code[-1] == '}'))
    393 					force_nl = false;
    394 
    395 				if (sc_end == 0) {	/* ignore buffering if
    396 							 * comment wasnt saved
    397 							 * up */
    398 					ps.search_brace = false;
    399 					goto check_type;
    400 				}
    401 				if (force_nl) {	/* if we should insert a nl
    402 						 * here, put it into the
    403 						 * buffer */
    404 					force_nl = false;
    405 					--line_no;	/* this will be
    406 							 * re-increased when the
    407 							 * nl is read from the
    408 							 * buffer */
    409 					*sc_end++ = '\n';
    410 					*sc_end++ = ' ';
    411 					if (verbose && !flushed_nl)	/* print error msg if
    412 									 * the line was not
    413 									 * already broken */
    414 						diag(0, "Line broken");
    415 					flushed_nl = false;
    416 				}
    417 				for (t_ptr = token; *t_ptr; ++t_ptr)
    418 					*sc_end++ = *t_ptr;	/* copy token into temp
    419 								 * buffer */
    420 				ps.procname[0] = 0;
    421 
    422 		sw_buffer:
    423 				ps.search_brace = false;	/* stop looking for
    424 								 * start of stmt */
    425 				bp_save = buf_ptr;	/* save current input
    426 							 * buffer */
    427 				be_save = buf_end;
    428 				buf_ptr = save_com;	/* fix so that
    429 							 * subsequent calls to
    430 							 * lexi will take tokens
    431 							 * out of save_com */
    432 				*sc_end++ = ' ';	/* add trailing blank,
    433 							 * just in case */
    434 				buf_end = sc_end;
    435 				sc_end = 0;
    436 				break;
    437 			}	/* end of switch */
    438 			if (type_code != 0)	/* we must make this check,
    439 						 * just in case there was an
    440 						 * unexpected EOF */
    441 				type_code = lexi();	/* read another token */
    442 			/* if (ps.search_brace) ps.procname[0] = 0; */
    443 			if ((is_procname = ps.procname[0]) && flushed_nl
    444 			    && !procnames_start_line && ps.in_decl
    445 			    && type_code == ident)
    446 				flushed_nl = 0;
    447 		}		/* end of while (search_brace) */
    448 		last_else = 0;
    449 check_type:
    450 		if (type_code == 0) {	/* we got eof */
    451 			if (s_lab != e_lab || s_code != e_code
    452 			    || s_com != e_com)	/* must dump end of line */
    453 				dump_line();
    454 			if (ps.tos > 1)	/* check for balanced braces */
    455 				diag(1, "Stuff missing from end of file.");
    456 
    457 			if (verbose) {
    458 				printf("There were %d output lines and %d comments\n",
    459 				    ps.out_lines, ps.out_coms);
    460 				printf("(Lines with comments)/(Lines with code): %6.3f\n",
    461 				    (1.0 * ps.com_lines) / code_lines);
    462 			}
    463 			fflush(output);
    464 			exit(found_err);
    465 		}
    466 		if (
    467 		    (type_code != comment) &&
    468 		    (type_code != newline) &&
    469 		    (type_code != preesc) &&
    470 		    (type_code != form_feed)) {
    471 			if (force_nl &&
    472 			    (type_code != semicolon) &&
    473 			    (type_code != lbrace || !btype_2)) {
    474 				/* we should force a broken line here */
    475 				if (verbose && !flushed_nl)
    476 					diag(0, "Line broken");
    477 				flushed_nl = false;
    478 				dump_line();
    479 				ps.want_blank = false;	/* dont insert blank at
    480 							 * line start */
    481 				force_nl = false;
    482 			}
    483 			ps.in_stmt = true;	/* turn on flag which causes
    484 						 * an extra level of
    485 						 * indentation. this is turned
    486 						 * off by a ; or '}' */
    487 			if (s_com != e_com) {	/* the turkey has embedded a
    488 						 * comment in a line. fix it */
    489 				*e_code++ = ' ';
    490 				for (t_ptr = s_com; *t_ptr; ++t_ptr) {
    491 					CHECK_SIZE_CODE;
    492 					*e_code++ = *t_ptr;
    493 				}
    494 				*e_code++ = ' ';
    495 				*e_code = '\0';	/* null terminate code sect */
    496 				ps.want_blank = false;
    497 				e_com = s_com;
    498 			}
    499 		} else
    500 			if (type_code != comment)	/* preserve force_nl
    501 							 * thru a comment */
    502 				force_nl = false;	/* cancel forced newline
    503 							 * after newline, form
    504 							 * feed, etc */
    505 
    506 
    507 
    508 		/*-----------------------------------------------------*\
    509 		|	   do switch on type of token scanned		|
    510 		\*-----------------------------------------------------*/
    511 		CHECK_SIZE_CODE;
    512 		switch (type_code) {	/* now, decide what to do with the
    513 					 * token */
    514 
    515 		case form_feed:/* found a form feed in line */
    516 			ps.use_ff = true;	/* a form feed is treated much
    517 						 * like a newline */
    518 			dump_line();
    519 			ps.want_blank = false;
    520 			break;
    521 
    522 		case newline:
    523 			if (ps.last_token != comma || ps.p_l_follow > 0
    524 			    || !ps.leave_comma || ps.block_init || !break_comma || s_com != e_com) {
    525 				dump_line();
    526 				ps.want_blank = false;
    527 			}
    528 			++line_no;	/* keep track of input line number */
    529 			break;
    530 
    531 		case lparen:	/* got a '(' or '[' */
    532 			++ps.p_l_follow;	/* count parens to make Healy
    533 						 * happy */
    534 			if (ps.want_blank && *token != '[' &&
    535 			    (ps.last_token != ident || proc_calls_space
    536 				|| (ps.its_a_keyword && (!ps.sizeof_keyword || Bill_Shannon))))
    537 				*e_code++ = ' ';
    538 			if (ps.in_decl && !ps.block_init) {
    539 				if (troff && !ps.dumped_decl_indent && !is_procname && ps.last_token == decl) {
    540 					ps.dumped_decl_indent = 1;
    541 					sprintf(e_code, "\n.Du %dp+\200p \"%s\"\n", dec_ind * 7, token);
    542 					e_code += strlen(e_code);
    543 				} else {
    544 					while ((e_code - s_code) < dec_ind) {
    545 						CHECK_SIZE_CODE;
    546 						*e_code++ = ' ';
    547 					}
    548 					*e_code++ = token[0];
    549 				}
    550 			} else
    551 				*e_code++ = token[0];
    552 			ps.paren_indents[ps.p_l_follow - 1] = e_code - s_code;
    553 			if (sp_sw && ps.p_l_follow == 1 && extra_expression_indent
    554 			    && ps.paren_indents[0] < 2 * ps.ind_size)
    555 				ps.paren_indents[0] = 2 * ps.ind_size;
    556 			ps.want_blank = false;
    557 			if (ps.in_or_st && *token == '(' && ps.tos <= 2) {
    558 				/*
    559 				 * this is a kluge to make sure that declarations will be
    560 				 * aligned right if proc decl has an explicit type on it, i.e.
    561 				 * "int a(x) {..."
    562 				 */
    563 				parse(semicolon);	/* I said this was a
    564 							 * kluge... */
    565 				ps.in_or_st = false;	/* turn off flag for
    566 							 * structure decl or
    567 							 * initialization */
    568 			}
    569 			if (ps.sizeof_keyword)
    570 				ps.sizeof_mask |= 1 << ps.p_l_follow;
    571 			break;
    572 
    573 		case rparen:	/* got a ')' or ']' */
    574 			rparen_count--;
    575 			if (ps.cast_mask & (1 << ps.p_l_follow) & ~ps.sizeof_mask) {
    576 				ps.last_u_d = true;
    577 				ps.cast_mask &= (1 << ps.p_l_follow) - 1;
    578 			}
    579 			ps.sizeof_mask &= (1 << ps.p_l_follow) - 1;
    580 			if (--ps.p_l_follow < 0) {
    581 				ps.p_l_follow = 0;
    582 				diag(0, "Extra %c", *token);
    583 			}
    584 			if (e_code == s_code)	/* if the paren starts the
    585 						 * line */
    586 				ps.paren_level = ps.p_l_follow;	/* then indent it */
    587 
    588 			*e_code++ = token[0];
    589 			ps.want_blank = true;
    590 
    591 			if (sp_sw && (ps.p_l_follow == 0)) {	/* check for end of if
    592 								 * (...), or some such */
    593 				sp_sw = false;
    594 				force_nl = true;	/* must force newline
    595 							 * after if */
    596 				ps.last_u_d = true;	/* inform lexi that a
    597 							 * following operator is
    598 							 * unary */
    599 				ps.in_stmt = false;	/* dont use stmt
    600 							 * continuation
    601 							 * indentation */
    602 
    603 				parse(hd_type);	/* let parser worry about if,
    604 						 * or whatever */
    605 			}
    606 			ps.search_brace = btype_2;	/* this should insure
    607 							 * that constructs such
    608 							 * as main(){...} and
    609 							 * int[]{...} have their
    610 							 * braces put in the
    611 							 * right place */
    612 			break;
    613 
    614 		case unary_op:	/* this could be any unary operation */
    615 			if (ps.want_blank)
    616 				*e_code++ = ' ';
    617 
    618 			if (troff && !ps.dumped_decl_indent && ps.in_decl && !is_procname) {
    619 				sprintf(e_code, "\n.Du %dp+\200p \"%s\"\n", dec_ind * 7, token);
    620 				ps.dumped_decl_indent = 1;
    621 				e_code += strlen(e_code);
    622 			} else {
    623 				char   *res = token;
    624 
    625 				if (ps.in_decl && !ps.block_init) {	/* if this is a unary op
    626 									 * in a declaration, we
    627 									 * should indent this
    628 									 * token */
    629 					for (i = 0; token[i]; ++i);	/* find length of token */
    630 					while ((e_code - s_code) < (dec_ind - i)) {
    631 						CHECK_SIZE_CODE;
    632 						*e_code++ = ' ';	/* pad it */
    633 					}
    634 				}
    635 				if (troff && token[0] == '-' && token[1] == '>')
    636 					res = "\\(->";
    637 				for (t_ptr = res; *t_ptr; ++t_ptr) {
    638 					CHECK_SIZE_CODE;
    639 					*e_code++ = *t_ptr;
    640 				}
    641 			}
    642 			ps.want_blank = false;
    643 			break;
    644 
    645 		case binary_op:/* any binary operation */
    646 			if (ps.want_blank)
    647 				*e_code++ = ' ';
    648 			{
    649 				char   *res = token;
    650 
    651 				if (troff)
    652 					switch (token[0]) {
    653 					case '<':
    654 						if (token[1] == '=')
    655 							res = "\\(<=";
    656 						break;
    657 					case '>':
    658 						if (token[1] == '=')
    659 							res = "\\(>=";
    660 						break;
    661 					case '!':
    662 						if (token[1] == '=')
    663 							res = "\\(!=";
    664 						break;
    665 					case '|':
    666 						if (token[1] == '|')
    667 							res = "\\(br\\(br";
    668 						else
    669 							if (token[1] == 0)
    670 								res = "\\(br";
    671 						break;
    672 					}
    673 				for (t_ptr = res; *t_ptr; ++t_ptr) {
    674 					CHECK_SIZE_CODE;
    675 					*e_code++ = *t_ptr;	/* move the operator */
    676 				}
    677 			}
    678 			ps.want_blank = true;
    679 			break;
    680 
    681 		case postop:	/* got a trailing ++ or -- */
    682 			*e_code++ = token[0];
    683 			*e_code++ = token[1];
    684 			ps.want_blank = true;
    685 			break;
    686 
    687 		case question:	/* got a ? */
    688 			squest++;	/* this will be used when a later
    689 					 * colon appears so we can distinguish
    690 					 * the <c>?<n>:<n> construct */
    691 			if (ps.want_blank)
    692 				*e_code++ = ' ';
    693 			*e_code++ = '?';
    694 			ps.want_blank = true;
    695 			break;
    696 
    697 		case casestmt:	/* got word 'case' or 'default' */
    698 			scase = true;	/* so we can process the later colon
    699 					 * properly */
    700 			goto copy_id;
    701 
    702 		case colon:	/* got a ':' */
    703 			if (squest > 0) {	/* it is part of the <c>?<n>:
    704 						 * <n> construct */
    705 				--squest;
    706 				if (ps.want_blank)
    707 					*e_code++ = ' ';
    708 				*e_code++ = ':';
    709 				ps.want_blank = true;
    710 				break;
    711 			}
    712 			if (ps.in_decl) {
    713 				*e_code++ = ':';
    714 				ps.want_blank = false;
    715 				break;
    716 			}
    717 			ps.in_stmt = false;	/* seeing a label does not
    718 						 * imply we are in a stmt */
    719 			for (t_ptr = s_code; *t_ptr; ++t_ptr)
    720 				*e_lab++ = *t_ptr;	/* turn everything so
    721 							 * far into a label */
    722 			e_code = s_code;
    723 			*e_lab++ = ':';
    724 			*e_lab++ = ' ';
    725 			*e_lab = '\0';
    726 
    727 			force_nl = ps.pcase = scase;	/* ps.pcase will be used
    728 							 * by dump_line to
    729 							 * decide how to indent
    730 							 * the label. force_nl
    731 							 * will force a case n:
    732 							 * to be on a line by
    733 							 * itself */
    734 			scase = false;
    735 			ps.want_blank = false;
    736 			break;
    737 
    738 		case semicolon:/* got a ';' */
    739 			ps.in_or_st = false;	/* we are not in an
    740 						 * initialization or structure
    741 						 * declaration */
    742 			scase = false;	/* these will only need resetting in a
    743 					 * error */
    744 			squest = 0;
    745 			if (ps.last_token == rparen && rparen_count == 0)
    746 				ps.in_parameter_declaration = 0;
    747 			ps.cast_mask = 0;
    748 			ps.sizeof_mask = 0;
    749 			ps.block_init = 0;
    750 			ps.block_init_level = 0;
    751 			ps.just_saw_decl--;
    752 
    753 			if (ps.in_decl && s_code == e_code && !ps.block_init)
    754 				while ((e_code - s_code) < (dec_ind - 1)) {
    755 					CHECK_SIZE_CODE;
    756 					*e_code++ = ' ';
    757 				}
    758 
    759 			ps.in_decl = (ps.dec_nest > 0);	/* if we were in a first
    760 							 * level structure
    761 							 * declaration, we arent
    762 							 * any more */
    763 
    764 			if ((!sp_sw || hd_type != forstmt) && ps.p_l_follow > 0) {
    765 
    766 				/*
    767 				 * This should be true iff there were unbalanced parens in the
    768 				 * stmt.  It is a bit complicated, because the semicolon might
    769 				 * be in a for stmt
    770 				 */
    771 				diag(1, "Unbalanced parens");
    772 				ps.p_l_follow = 0;
    773 				if (sp_sw) {	/* this is a check for a if,
    774 						 * while, etc. with unbalanced
    775 						 * parens */
    776 					sp_sw = false;
    777 					parse(hd_type);	/* dont lose the if, or
    778 							 * whatever */
    779 				}
    780 			}
    781 			*e_code++ = ';';
    782 			ps.want_blank = true;
    783 			ps.in_stmt = (ps.p_l_follow > 0);	/* we are no longer in
    784 								 * the middle of a stmt */
    785 
    786 			if (!sp_sw) {	/* if not if for (;;) */
    787 				parse(semicolon);	/* let parser know about
    788 							 * end of stmt */
    789 				force_nl = true;	/* force newline after a
    790 							 * end of stmt */
    791 			}
    792 			break;
    793 
    794 		case lbrace:	/* got a '{' */
    795 			ps.in_stmt = false;	/* dont indent the {} */
    796 			if (!ps.block_init)
    797 				force_nl = true;	/* force other stuff on
    798 							 * same line as '{' onto
    799 							 * new line */
    800 			else
    801 				if (ps.block_init_level <= 0)
    802 					ps.block_init_level = 1;
    803 				else
    804 					ps.block_init_level++;
    805 
    806 			if (s_code != e_code && !ps.block_init) {
    807 				if (!btype_2) {
    808 					dump_line();
    809 					ps.want_blank = false;
    810 				} else
    811 					if (ps.in_parameter_declaration && !ps.in_or_st) {
    812 						ps.i_l_follow = 0;
    813 						dump_line();
    814 						ps.want_blank = false;
    815 					}
    816 			}
    817 			if (ps.in_parameter_declaration)
    818 				prefix_blankline_requested = 0;
    819 
    820 			if (ps.p_l_follow > 0) {	/* check for preceeding
    821 							 * unbalanced parens */
    822 				diag(1, "Unbalanced parens");
    823 				ps.p_l_follow = 0;
    824 				if (sp_sw) {	/* check for unclosed if, for,
    825 						 * etc. */
    826 					sp_sw = false;
    827 					parse(hd_type);
    828 					ps.ind_level = ps.i_l_follow;
    829 				}
    830 			}
    831 			if (s_code == e_code)
    832 				ps.ind_stmt = false;	/* dont put extra
    833 							 * indentation on line
    834 							 * with '{' */
    835 			if (ps.in_decl && ps.in_or_st) {	/* this is either a
    836 								 * structure declaration
    837 								 * or an init */
    838 				di_stack[ps.dec_nest++] = dec_ind;
    839 				/* ?		dec_ind = 0; */
    840 			} else {
    841 				ps.decl_on_line = false;	/* we cant be in the
    842 								 * middle of a
    843 								 * declaration, so dont
    844 								 * do special
    845 								 * indentation of
    846 								 * comments */
    847 				if (blanklines_after_declarations_at_proctop
    848 				    && ps.in_parameter_declaration)
    849 					postfix_blankline_requested = 1;
    850 				ps.in_parameter_declaration = 0;
    851 			}
    852 			dec_ind = 0;
    853 			parse(lbrace);	/* let parser know about this */
    854 			if (ps.want_blank)	/* put a blank before '{' if
    855 						 * '{' is not at start of line */
    856 				*e_code++ = ' ';
    857 			ps.want_blank = false;
    858 			*e_code++ = '{';
    859 			ps.just_saw_decl = 0;
    860 			break;
    861 
    862 		case rbrace:	/* got a '}' */
    863 			if (ps.p_stack[ps.tos] == decl && !ps.block_init)	/* semicolons can be
    864 										 * omitted in
    865 										 * declarations */
    866 				parse(semicolon);
    867 			if (ps.p_l_follow) {	/* check for unclosed if, for,
    868 						 * else. */
    869 				diag(1, "Unbalanced parens");
    870 				ps.p_l_follow = 0;
    871 				sp_sw = false;
    872 			}
    873 			ps.just_saw_decl = 0;
    874 			ps.block_init_level--;
    875 			if (s_code != e_code && !ps.block_init) {	/* '}' must be first on
    876 									 * line */
    877 				if (verbose)
    878 					diag(0, "Line broken");
    879 				dump_line();
    880 			}
    881 			*e_code++ = '}';
    882 			ps.want_blank = true;
    883 			ps.in_stmt = ps.ind_stmt = false;
    884 			if (ps.dec_nest > 0) {	/* we are in multi-level
    885 						 * structure declaration */
    886 				dec_ind = di_stack[--ps.dec_nest];
    887 				if (ps.dec_nest == 0 && !ps.in_parameter_declaration)
    888 					ps.just_saw_decl = 2;
    889 				ps.in_decl = true;
    890 			}
    891 			prefix_blankline_requested = 0;
    892 			parse(rbrace);	/* let parser know about this */
    893 			ps.search_brace = cuddle_else && ps.p_stack[ps.tos] == ifhead
    894 			    && ps.il[ps.tos] >= ps.ind_level;
    895 			if (ps.tos <= 1 && blanklines_after_procs && ps.dec_nest <= 0)
    896 				postfix_blankline_requested = 1;
    897 			break;
    898 
    899 		case swstmt:	/* got keyword "switch" */
    900 			sp_sw = true;
    901 			hd_type = swstmt;	/* keep this for when we have
    902 						 * seen the expression */
    903 			goto copy_id;	/* go move the token into buffer */
    904 
    905 		case sp_paren:	/* token is if, while, for */
    906 			sp_sw = true;	/* the interesting stuff is done after
    907 					 * the expression is scanned */
    908 			hd_type = (*token == 'i' ? ifstmt :
    909 			    (*token == 'w' ? whilestmt : forstmt));
    910 
    911 			/*
    912 		         * remember the type of header for later use by parser
    913 		         */
    914 			goto copy_id;	/* copy the token into line */
    915 
    916 		case sp_nparen:/* got else, do */
    917 			ps.in_stmt = false;
    918 			if (*token == 'e') {
    919 				if (e_code != s_code && (!cuddle_else || e_code[-1] != '}')) {
    920 					if (verbose)
    921 						diag(0, "Line broken");
    922 					dump_line();	/* make sure this starts
    923 							 * a line */
    924 					ps.want_blank = false;
    925 				}
    926 				force_nl = true;	/* also, following stuff
    927 							 * must go onto new line */
    928 				last_else = 1;
    929 				parse(elselit);
    930 			} else {
    931 				if (e_code != s_code) {	/* make sure this starts
    932 							 * a line */
    933 					if (verbose)
    934 						diag(0, "Line broken");
    935 					dump_line();
    936 					ps.want_blank = false;
    937 				}
    938 				force_nl = true;	/* also, following stuff
    939 							 * must go onto new line */
    940 				last_else = 0;
    941 				parse(dolit);
    942 			}
    943 			goto copy_id;	/* move the token into line */
    944 
    945 		case decl:	/* we have a declaration type (int, register,
    946 				 * etc.) */
    947 			parse(decl);	/* let parser worry about indentation */
    948 			if (ps.last_token == rparen && ps.tos <= 1) {
    949 				ps.in_parameter_declaration = 1;
    950 				if (s_code != e_code) {
    951 					dump_line();
    952 					ps.want_blank = 0;
    953 				}
    954 			}
    955 			if (ps.in_parameter_declaration && ps.indent_parameters && ps.dec_nest == 0) {
    956 				ps.ind_level = ps.i_l_follow = 1;
    957 				ps.ind_stmt = 0;
    958 			}
    959 			ps.in_or_st = true;	/* this might be a structure
    960 						 * or initialization
    961 						 * declaration */
    962 			ps.in_decl = ps.decl_on_line = true;
    963 			if ( /* !ps.in_or_st && */ ps.dec_nest <= 0)
    964 				ps.just_saw_decl = 2;
    965 			prefix_blankline_requested = 0;
    966 			for (i = 0; token[i++];);	/* get length of token */
    967 
    968 			/*
    969 		         * dec_ind = e_code - s_code + (ps.decl_indent>i ? ps.decl_indent
    970 		         * : i);
    971 		         */
    972 			dec_ind = ps.decl_indent > 0 ? ps.decl_indent : i;
    973 			goto copy_id;
    974 
    975 		case ident:	/* got an identifier or constant */
    976 			if (ps.in_decl) {	/* if we are in a declaration,
    977 						 * we must indent identifier */
    978 				if (ps.want_blank)
    979 					*e_code++ = ' ';
    980 				ps.want_blank = false;
    981 				if (is_procname == 0 || !procnames_start_line) {
    982 					if (!ps.block_init) {
    983 						if (troff && !ps.dumped_decl_indent) {
    984 							sprintf(e_code, "\n.De %dp+\200p\n", dec_ind * 7);
    985 							ps.dumped_decl_indent = 1;
    986 							e_code += strlen(e_code);
    987 						} else
    988 							while ((e_code - s_code) < dec_ind) {
    989 								CHECK_SIZE_CODE;
    990 								*e_code++ = ' ';
    991 							}
    992 					}
    993 				} else {
    994 					if (dec_ind && s_code != e_code)
    995 						dump_line();
    996 					dec_ind = 0;
    997 					ps.want_blank = false;
    998 				}
    999 			} else
   1000 				if (sp_sw && ps.p_l_follow == 0) {
   1001 					sp_sw = false;
   1002 					force_nl = true;
   1003 					ps.last_u_d = true;
   1004 					ps.in_stmt = false;
   1005 					parse(hd_type);
   1006 				}
   1007 	copy_id:
   1008 			if (ps.want_blank)
   1009 				*e_code++ = ' ';
   1010 			if (troff && ps.its_a_keyword) {
   1011 				e_code = chfont(&bodyf, &keywordf, e_code);
   1012 				for (t_ptr = token; *t_ptr; ++t_ptr) {
   1013 					CHECK_SIZE_CODE;
   1014 					*e_code++ = keywordf.allcaps && islower((unsigned char)*t_ptr)
   1015 					    ? toupper(*t_ptr) : *t_ptr;
   1016 				}
   1017 				e_code = chfont(&keywordf, &bodyf, e_code);
   1018 			} else
   1019 				for (t_ptr = token; *t_ptr; ++t_ptr) {
   1020 					CHECK_SIZE_CODE;
   1021 					*e_code++ = *t_ptr;
   1022 				}
   1023 			ps.want_blank = true;
   1024 			break;
   1025 
   1026 		case period:	/* treat a period kind of like a binary
   1027 				 * operation */
   1028 			*e_code++ = '.';	/* move the period into line */
   1029 			ps.want_blank = false;	/* dont put a blank after a
   1030 						 * period */
   1031 			break;
   1032 
   1033 		case comma:
   1034 			ps.want_blank = (s_code != e_code);	/* only put blank after
   1035 								 * comma if comma does
   1036 								 * not start the line */
   1037 			if (ps.in_decl && is_procname == 0 && !ps.block_init)
   1038 				while ((e_code - s_code) < (dec_ind - 1)) {
   1039 					CHECK_SIZE_CODE;
   1040 					*e_code++ = ' ';
   1041 				}
   1042 
   1043 			*e_code++ = ',';
   1044 			if (ps.p_l_follow == 0) {
   1045 				if (ps.block_init_level <= 0)
   1046 					ps.block_init = 0;
   1047 				if (break_comma && (!ps.leave_comma || compute_code_target() + (e_code - s_code) > max_col - 8))
   1048 					force_nl = true;
   1049 			}
   1050 			break;
   1051 
   1052 		case preesc:	/* got the character '#' */
   1053 			if ((s_com != e_com) ||
   1054 			    (s_lab != e_lab) ||
   1055 			    (s_code != e_code))
   1056 				dump_line();
   1057 			*e_lab++ = '#';	/* move whole line to 'label' buffer */
   1058 			{
   1059 				int     in_comment = 0;
   1060 				int     com_start = 0;
   1061 				char    quote = 0;
   1062 				int     com_end = 0;
   1063 
   1064 				while (*buf_ptr == ' ' || *buf_ptr == '\t') {
   1065 					buf_ptr++;
   1066 					if (buf_ptr >= buf_end)
   1067 						fill_buffer();
   1068 				}
   1069 				while (*buf_ptr != '\n' || in_comment) {
   1070 					CHECK_SIZE_LAB;
   1071 					*e_lab = *buf_ptr++;
   1072 					if (buf_ptr >= buf_end)
   1073 						fill_buffer();
   1074 					switch (*e_lab++) {
   1075 					case BACKSLASH:
   1076 						if (troff)
   1077 							*e_lab++ = BACKSLASH;
   1078 						if (!in_comment) {
   1079 							*e_lab++ = *buf_ptr++;
   1080 							if (buf_ptr >= buf_end)
   1081 								fill_buffer();
   1082 						}
   1083 						break;
   1084 					case '/':
   1085 						if (*buf_ptr == '*' && !in_comment && !quote) {
   1086 							in_comment = 1;
   1087 							*e_lab++ = *buf_ptr++;
   1088 							com_start = e_lab - s_lab - 2;
   1089 						}
   1090 						break;
   1091 					case '"':
   1092 						if (quote == '"')
   1093 							quote = 0;
   1094 						break;
   1095 					case '\'':
   1096 						if (quote == '\'')
   1097 							quote = 0;
   1098 						break;
   1099 					case '*':
   1100 						if (*buf_ptr == '/' && in_comment) {
   1101 							in_comment = 0;
   1102 							*e_lab++ = *buf_ptr++;
   1103 							com_end = e_lab - s_lab;
   1104 						}
   1105 						break;
   1106 					}
   1107 				}
   1108 
   1109 				while (e_lab > s_lab && (e_lab[-1] == ' ' || e_lab[-1] == '\t'))
   1110 					e_lab--;
   1111 				if (e_lab - s_lab == com_end && bp_save == 0) {	/* comment on
   1112 										 * preprocessor line */
   1113 					if (sc_end == 0)	/* if this is the first
   1114 								 * comment, we must set
   1115 								 * up the buffer */
   1116 						sc_end = &(save_com[0]);
   1117 					else {
   1118 						*sc_end++ = '\n';	/* add newline between
   1119 									 * comments */
   1120 						*sc_end++ = ' ';
   1121 						--line_no;
   1122 					}
   1123 					memmove(sc_end, s_lab + com_start, com_end - com_start);
   1124 					sc_end += com_end - com_start;
   1125 					if (sc_end >= &save_com[sc_size])
   1126 						abort();
   1127 					e_lab = s_lab + com_start;
   1128 					while (e_lab > s_lab && (e_lab[-1] == ' ' || e_lab[-1] == '\t'))
   1129 						e_lab--;
   1130 					bp_save = buf_ptr;	/* save current input
   1131 								 * buffer */
   1132 					be_save = buf_end;
   1133 					buf_ptr = save_com;	/* fix so that
   1134 								 * subsequent calls to
   1135 								 * lexi will take tokens
   1136 								 * out of save_com */
   1137 					*sc_end++ = ' ';	/* add trailing blank,
   1138 								 * just in case */
   1139 					buf_end = sc_end;
   1140 					sc_end = 0;
   1141 				}
   1142 				*e_lab = '\0';	/* null terminate line */
   1143 				ps.pcase = false;
   1144 			}
   1145 
   1146 			if (strncmp(s_lab, "#if", 3) == 0) {
   1147 				if (blanklines_around_conditional_compilation) {
   1148 					int     c;
   1149 					prefix_blankline_requested++;
   1150 					while ((c = getc(input)) == '\n');
   1151 					ungetc(c, input);
   1152 				}
   1153 				if (ifdef_level < sizeof state_stack / sizeof state_stack[0]) {
   1154 					match_state[ifdef_level].tos = -1;
   1155 					state_stack[ifdef_level++] = ps;
   1156 				} else
   1157 					diag(1, "#if stack overflow");
   1158 			} else
   1159 				if (strncmp(s_lab, "#else", 5) == 0) {
   1160 					if (ifdef_level <= 0)
   1161 						diag(1, "Unmatched #else");
   1162 					else {
   1163 						match_state[ifdef_level - 1] = ps;
   1164 						ps = state_stack[ifdef_level - 1];
   1165 					}
   1166 				} else
   1167 					if (strncmp(s_lab, "#endif", 6) == 0) {
   1168 						if (ifdef_level <= 0)
   1169 							diag(1, "Unmatched #endif");
   1170 						else {
   1171 							ifdef_level--;
   1172 
   1173 #ifdef undef
   1174 							/*
   1175 						         * This match needs to be more intelligent before the
   1176 						         * message is useful
   1177 						         */
   1178 							if (match_state[ifdef_level].tos >= 0
   1179 							    && memcmp(&ps, &match_state[ifdef_level], sizeof ps))
   1180 								diag(0, "Syntactically inconsistant #ifdef alternatives.");
   1181 #endif
   1182 						}
   1183 						if (blanklines_around_conditional_compilation) {
   1184 							postfix_blankline_requested++;
   1185 							n_real_blanklines = 0;
   1186 						}
   1187 					}
   1188 			break;	/* subsequent processing of the newline
   1189 				 * character will cause the line to be printed */
   1190 
   1191 		case comment:	/* we have gotten a start comment */
   1192 			/* this is a biggie */
   1193 			if (flushed_nl) {	/* we should force a broken
   1194 						 * line here */
   1195 				flushed_nl = false;
   1196 				dump_line();
   1197 				ps.want_blank = false;	/* dont insert blank at
   1198 							 * line start */
   1199 				force_nl = false;
   1200 			}
   1201 			pr_comment();
   1202 			break;
   1203 		}		/* end of big switch stmt */
   1204 
   1205 		*e_code = '\0';	/* make sure code section is null terminated */
   1206 		if (type_code != comment && type_code != newline && type_code != preesc)
   1207 			ps.last_token = type_code;
   1208 	}			/* end of main while (1) loop */
   1209 }
   1210 /*
   1211  * copy input file to backup file if in_name is /blah/blah/blah/file, then
   1212  * backup file will be ".Bfile" then make the backup file the input and
   1213  * original input file the output
   1214  */
   1215 void
   1216 bakcopy()
   1217 {
   1218 	int     n, bakchn;
   1219 	char    buff[8 * 1024];
   1220 	char   *p;
   1221 
   1222 	/* construct file name .Bfile */
   1223 	for (p = in_name; *p; p++);	/* skip to end of string */
   1224 	while (p > in_name && *p != '/')	/* find last '/' */
   1225 		p--;
   1226 	if (*p == '/')
   1227 		p++;
   1228 	sprintf(bakfile, "%s.BAK", p);
   1229 
   1230 	/* copy in_name to backup file */
   1231 	bakchn = creat(bakfile, 0600);
   1232 	if (bakchn < 0)
   1233 		err(1, "%s", bakfile);
   1234 	while ((n = read(fileno(input), buff, sizeof buff)) > 0)
   1235 		if (write(bakchn, buff, n) != n)
   1236 			err(1, "%s", bakfile);
   1237 	if (n < 0)
   1238 		err(1, "%s", in_name);
   1239 	close(bakchn);
   1240 	fclose(input);
   1241 
   1242 	/* re-open backup file as the input file */
   1243 	input = fopen(bakfile, "r");
   1244 	if (input == 0)
   1245 		err(1, "%s", bakfile);
   1246 	/* now the original input file will be the output */
   1247 	output = fopen(in_name, "w");
   1248 	if (output == 0) {
   1249 		unlink(bakfile);
   1250 		err(1, "%s", in_name);
   1251 	}
   1252 }
   1253