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collect.c revision 1.24
      1 /*	$NetBSD: collect.c,v 1.24 2002/03/04 03:07:25 wiz Exp $	*/
      2 
      3 /*
      4  * Copyright (c) 1980, 1993
      5  *	The Regents of the University of California.  All rights reserved.
      6  *
      7  * Redistribution and use in source and binary forms, with or without
      8  * modification, are permitted provided that the following conditions
      9  * are met:
     10  * 1. Redistributions of source code must retain the above copyright
     11  *    notice, this list of conditions and the following disclaimer.
     12  * 2. Redistributions in binary form must reproduce the above copyright
     13  *    notice, this list of conditions and the following disclaimer in the
     14  *    documentation and/or other materials provided with the distribution.
     15  * 3. All advertising materials mentioning features or use of this software
     16  *    must display the following acknowledgement:
     17  *	This product includes software developed by the University of
     18  *	California, Berkeley and its contributors.
     19  * 4. Neither the name of the University nor the names of its contributors
     20  *    may be used to endorse or promote products derived from this software
     21  *    without specific prior written permission.
     22  *
     23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     33  * SUCH DAMAGE.
     34  */
     35 
     36 #include <sys/cdefs.h>
     37 #ifndef lint
     38 #if 0
     39 static char sccsid[] = "@(#)collect.c	8.2 (Berkeley) 4/19/94";
     40 #else
     41 __RCSID("$NetBSD: collect.c,v 1.24 2002/03/04 03:07:25 wiz Exp $");
     42 #endif
     43 #endif /* not lint */
     44 
     45 /*
     46  * Mail -- a mail program
     47  *
     48  * Collect input from standard input, handling
     49  * ~ escapes.
     50  */
     51 
     52 #include "rcv.h"
     53 #include "extern.h"
     54 
     55 extern char *tempMail;
     56 extern char *tempEdit;
     57 
     58 /*
     59  * Read a message from standard output and return a read file to it
     60  * or NULL on error.
     61  */
     62 
     63 /*
     64  * The following hokiness with global variables is so that on
     65  * receipt of an interrupt signal, the partial message can be salted
     66  * away on dead.letter.
     67  */
     68 
     69 static	sig_t	saveint;		/* Previous SIGINT value */
     70 static	sig_t	savehup;		/* Previous SIGHUP value */
     71 static	sig_t	savetstp;		/* Previous SIGTSTP value */
     72 static	sig_t	savettou;		/* Previous SIGTTOU value */
     73 static	sig_t	savettin;		/* Previous SIGTTIN value */
     74 static	FILE	*collf;			/* File for saving away */
     75 static	int	hadintr;		/* Have seen one SIGINT so far */
     76 
     77 static	jmp_buf	colljmp;		/* To get back to work */
     78 static	int	colljmp_p;		/* whether to long jump */
     79 static	jmp_buf	collabort;		/* To end collection with error */
     80 
     81 FILE *
     82 collect(struct header *hp, int printheaders)
     83 {
     84 	FILE *fbuf;
     85 	int lc, cc, escape, eofcount;
     86 	int c, t;
     87 	char linebuf[LINESIZE], *cp;
     88 	char getsub;
     89 	sigset_t nset;
     90 	int longline, lastlong, rc;	/* So we don't make 2 or more lines
     91 					   out of a long input line. */
     92 #if __GNUC__
     93 	/* Avoid longjmp clobbering */
     94 	(void) &escape;
     95 	(void) &eofcount;
     96 	(void) &getsub;
     97 	(void) &longline;
     98 #endif
     99 
    100 	collf = NULL;
    101 	/*
    102 	 * Start catching signals from here, but we're still die on interrupts
    103 	 * until we're in the main loop.
    104 	 */
    105 	sigemptyset(&nset);
    106 	sigaddset(&nset, SIGINT);
    107 	sigaddset(&nset, SIGHUP);
    108 	sigprocmask(SIG_BLOCK, &nset, NULL);
    109 	if ((saveint = signal(SIGINT, SIG_IGN)) != SIG_IGN)
    110 		signal(SIGINT, collint);
    111 	if ((savehup = signal(SIGHUP, SIG_IGN)) != SIG_IGN)
    112 		signal(SIGHUP, collhup);
    113 	savetstp = signal(SIGTSTP, collstop);
    114 	savettou = signal(SIGTTOU, collstop);
    115 	savettin = signal(SIGTTIN, collstop);
    116 	if (setjmp(collabort) || setjmp(colljmp)) {
    117 		rm(tempMail);
    118 		goto err;
    119 	}
    120 	sigprocmask(SIG_UNBLOCK, &nset, NULL);
    121 
    122 	noreset++;
    123 	if ((collf = Fopen(tempMail, "w+")) == NULL) {
    124 		perror(tempMail);
    125 		goto err;
    126 	}
    127 	unlink(tempMail);
    128 
    129 	/*
    130 	 * If we are going to prompt for a subject,
    131 	 * refrain from printing a newline after
    132 	 * the headers (since some people mind).
    133 	 */
    134 	t = GTO|GSUBJECT|GCC|GNL;
    135 	getsub = 0;
    136 	if (hp->h_subject == NULL && value("interactive") != NULL &&
    137 	    (value("ask") != NULL || value("asksub") != NULL))
    138 		t &= ~GNL, getsub++;
    139 	if (printheaders) {
    140 		puthead(hp, stdout, t);
    141 		fflush(stdout);
    142 	}
    143 	if ((cp = value("escape")) != NULL)
    144 		escape = *cp;
    145 	else
    146 		escape = ESCAPE;
    147 	eofcount = 0;
    148 	hadintr = 0;
    149 	lastlong = 0;
    150 	longline = 0;
    151 
    152 	if (!setjmp(colljmp)) {
    153 		if (getsub)
    154 			grabh(hp, GSUBJECT);
    155 	} else {
    156 		/*
    157 		 * Come here for printing the after-signal message.
    158 		 * Duplicate messages won't be printed because
    159 		 * the write is aborted if we get a SIGTTOU.
    160 		 */
    161 cont:
    162 		if (hadintr) {
    163 			fflush(stdout);
    164 			fprintf(stderr,
    165 			"\n(Interrupt -- one more to kill letter)\n");
    166 		} else {
    167 			printf("(continue)\n");
    168 			fflush(stdout);
    169 		}
    170 	}
    171 	for (;;) {
    172 		colljmp_p = 1;
    173 		c = readline(stdin, linebuf, LINESIZE);
    174 		colljmp_p = 0;
    175 		if (c < 0) {
    176 			if (value("interactive") != NULL &&
    177 			    value("ignoreeof") != NULL && ++eofcount < 25) {
    178 				printf("Use \".\" to terminate letter\n");
    179 				continue;
    180 			}
    181 			break;
    182 		}
    183 		lastlong = longline;
    184 		longline = c == LINESIZE-1;
    185 		eofcount = 0;
    186 		hadintr = 0;
    187 		if (linebuf[0] == '.' && linebuf[1] == '\0' &&
    188 		    value("interactive") != NULL && !lastlong &&
    189 		    (value("dot") != NULL || value("ignoreeof") != NULL))
    190 			break;
    191 		if (linebuf[0] != escape || value("interactive") == NULL ||
    192 		    lastlong) {
    193 			if (putline(collf, linebuf, !longline) < 0)
    194 				goto err;
    195 			continue;
    196 		}
    197 		c = linebuf[1];
    198 		switch (c) {
    199 		default:
    200 			/*
    201 			 * On double escape, just send the single one.
    202 			 * Otherwise, it's an error.
    203 			 */
    204 			if (c == escape) {
    205 				if (putline(collf, &linebuf[1], !longline) < 0)
    206 					goto err;
    207 				else
    208 					break;
    209 			}
    210 			printf("Unknown tilde escape.\n");
    211 			break;
    212 		case 'C':
    213 			/*
    214 			 * Dump core.
    215 			 */
    216 			core(NULL);
    217 			break;
    218 		case '!':
    219 			/*
    220 			 * Shell escape, send the balance of the
    221 			 * line to sh -c.
    222 			 */
    223 			shell(&linebuf[2]);
    224 			break;
    225 		case ':':
    226 		case '_':
    227 			/*
    228 			 * Escape to command mode, but be nice!
    229 			 */
    230 			execute(&linebuf[2], 1);
    231 			goto cont;
    232 		case '.':
    233 			/*
    234 			 * Simulate end of file on input.
    235 			 */
    236 			goto out;
    237 		case 'q':
    238 			/*
    239 			 * Force a quit of sending mail.
    240 			 * Act like an interrupt happened.
    241 			 */
    242 			hadintr++;
    243 			collint(SIGINT);
    244 			exit(1);
    245 
    246 		case 'x':	/* exit, do not save in dead.letter */
    247 			goto err;
    248 
    249 		case 'h':
    250 			/*
    251 			 * Grab a bunch of headers.
    252 			 */
    253 			grabh(hp, GTO|GSUBJECT|GCC|GBCC);
    254 			goto cont;
    255 		case 't':
    256 			/*
    257 			 * Add to the To list.
    258 			 */
    259 			hp->h_to = cat(hp->h_to, extract(&linebuf[2], GTO));
    260 			break;
    261 		case 's':
    262 			/*
    263 			 * Set the Subject list.
    264 			 */
    265 			cp = &linebuf[2];
    266 			while (isspace((unsigned char)*cp))
    267 				cp++;
    268 			hp->h_subject = savestr(cp);
    269 			break;
    270 		case 'c':
    271 			/*
    272 			 * Add to the CC list.
    273 			 */
    274 			hp->h_cc = cat(hp->h_cc, extract(&linebuf[2], GCC));
    275 			break;
    276 		case 'b':
    277 			/*
    278 			 * Add stuff to blind carbon copies list.
    279 			 */
    280 			hp->h_bcc = cat(hp->h_bcc, extract(&linebuf[2], GBCC));
    281 			break;
    282 		case 'i':
    283 		case 'A':
    284 		case 'a':
    285 			/*
    286 			 * Insert named variable in message
    287 			 */
    288 
    289 			switch(c) {
    290 				case 'i':
    291 					cp = &linebuf[2];
    292 					while(isspace((unsigned char) *cp))
    293 						cp++;
    294 
    295 					break;
    296 				case 'a':
    297 					cp = "sign";
    298 					break;
    299 				case 'A':
    300 					cp = "Sign";
    301 					break;
    302 				default:
    303 					goto err;
    304 			}
    305 
    306 			if(*cp && (cp = value(cp)) != NULL) {
    307 				printf("%s\n", cp);
    308 				if(putline(collf, cp, 1) < 0)
    309 					goto err;
    310 			}
    311 
    312 			break;
    313 
    314 		case 'd':
    315 			strcpy(linebuf + 2, getdeadletter());
    316 			/* fall into . . . */
    317 		case 'r':
    318 		case '<':
    319 			/*
    320 			 * Invoke a file:
    321 			 * Search for the file name,
    322 			 * then open it and copy the contents to collf.
    323 			 */
    324 			cp = &linebuf[2];
    325 			while (isspace((unsigned char)*cp))
    326 				cp++;
    327 			if (*cp == '\0') {
    328 				printf("Interpolate what file?\n");
    329 				break;
    330 			}
    331 
    332 			cp = expand(cp);
    333 			if (cp == NULL)
    334 				break;
    335 
    336 			if (*cp == '!') {	/* insert stdout of command */
    337 				char *shellcmd;
    338 				int nullfd;
    339 				int rc2;
    340 
    341 				if((nullfd = open("/dev/null", O_RDONLY, 0)) == -1) {
    342 					perror("/dev/null");
    343 					break;
    344 				}
    345 
    346 				if ((fbuf = Fopen(tempEdit, "w+")) == NULL) {
    347 					perror(tempEdit);
    348 					break;
    349 				}
    350 				(void) unlink(tempEdit);
    351 
    352 				if ((shellcmd = value("SHELL")) == NULL)
    353 					shellcmd = _PATH_CSHELL;
    354 
    355 				rc2 = run_command(shellcmd, 0, nullfd, fileno(fbuf), "-c", cp+1, NULL);
    356 
    357 				close(nullfd);
    358 
    359 				if (rc2 < 0) {
    360 					(void) Fclose(fbuf);
    361 					break;
    362 				}
    363 
    364 				if (fsize(fbuf) == 0) {
    365 					fprintf(stderr, "No bytes from command \"%s\"\n", cp+1);
    366 					(void) Fclose(fbuf);
    367 					break;
    368 				}
    369 
    370 				rewind(fbuf);
    371 			}
    372 			else if (isdir(cp)) {
    373 				printf("%s: Directory\n", cp);
    374 				break;
    375 			}
    376 			else if ((fbuf = Fopen(cp, "r")) == NULL) {
    377 				perror(cp);
    378 				break;
    379 			}
    380 			printf("\"%s\" ", cp);
    381 			fflush(stdout);
    382 			lc = 0;
    383 			cc = 0;
    384 			while ((rc = readline(fbuf, linebuf, LINESIZE)) >= 0) {
    385 				if (rc != LINESIZE-1) lc++;
    386 				if ((t = putline(collf, linebuf,
    387 						 rc != LINESIZE-1)) < 0) {
    388 					Fclose(fbuf);
    389 					goto err;
    390 				}
    391 				cc += t;
    392 			}
    393 			Fclose(fbuf);
    394 			printf("%d/%d\n", lc, cc);
    395 			break;
    396 		case 'w':
    397 			/*
    398 			 * Write the message on a file.
    399 			 */
    400 			cp = &linebuf[2];
    401 			while (*cp == ' ' || *cp == '\t')
    402 				cp++;
    403 			if (*cp == '\0') {
    404 				fprintf(stderr, "Write what file!?\n");
    405 				break;
    406 			}
    407 			if ((cp = expand(cp)) == NULL)
    408 				break;
    409 			rewind(collf);
    410 			exwrite(cp, collf, 1);
    411 			break;
    412 		case 'm':
    413 		case 'M':
    414 		case 'f':
    415 		case 'F':
    416 			/*
    417 			 * Interpolate the named messages, if we
    418 			 * are in receiving mail mode.  Does the
    419 			 * standard list processing garbage.
    420 			 * If ~f is given, we don't shift over.
    421 			 */
    422 			if (forward(linebuf + 2, collf, c) < 0)
    423 				goto err;
    424 			goto cont;
    425 		case '?':
    426 			if ((fbuf = Fopen(_PATH_TILDE, "r")) == NULL) {
    427 				perror(_PATH_TILDE);
    428 				break;
    429 			}
    430 			while ((t = getc(fbuf)) != EOF)
    431 				(void) putchar(t);
    432 			Fclose(fbuf);
    433 			break;
    434 		case 'p':
    435 			/*
    436 			 * Print out the current state of the
    437 			 * message without altering anything.
    438 			 */
    439 			rewind(collf);
    440 			printf("-------\nMessage contains:\n");
    441 			puthead(hp, stdout, GTO|GSUBJECT|GCC|GBCC|GNL);
    442 			while ((t = getc(collf)) != EOF)
    443 				(void) putchar(t);
    444 			goto cont;
    445 		case '|':
    446 			/*
    447 			 * Pipe message through command.
    448 			 * Collect output as new message.
    449 			 */
    450 			rewind(collf);
    451 			mespipe(collf, &linebuf[2]);
    452 			goto cont;
    453 		case 'v':
    454 		case 'e':
    455 			/*
    456 			 * Edit the current message.
    457 			 * 'e' means to use EDITOR
    458 			 * 'v' means to use VISUAL
    459 			 */
    460 			rewind(collf);
    461 			mesedit(collf, c);
    462 			goto cont;
    463 		}
    464 	}
    465 	goto out;
    466 err:
    467 	if (collf != NULL) {
    468 		Fclose(collf);
    469 		collf = NULL;
    470 	}
    471 out:
    472 	if (collf != NULL)
    473 		rewind(collf);
    474 	noreset--;
    475 	sigprocmask(SIG_BLOCK, &nset, NULL);
    476 	signal(SIGINT, saveint);
    477 	signal(SIGHUP, savehup);
    478 	signal(SIGTSTP, savetstp);
    479 	signal(SIGTTOU, savettou);
    480 	signal(SIGTTIN, savettin);
    481 	sigprocmask(SIG_UNBLOCK, &nset, NULL);
    482 	return collf;
    483 }
    484 
    485 /*
    486  * Write a file, ex-like if f set.
    487  */
    488 int
    489 exwrite(char name[], FILE *fp, int f)
    490 {
    491 	FILE *of;
    492 	int c;
    493 	long cc;
    494 	int lc;
    495 	struct stat junk;
    496 
    497 	if (f) {
    498 		printf("\"%s\" ", name);
    499 		fflush(stdout);
    500 	}
    501 	if (stat(name, &junk) >= 0 && S_ISREG(junk.st_mode)) {
    502 		if (!f)
    503 			fprintf(stderr, "%s: ", name);
    504 		fprintf(stderr, "File exists\n");
    505 		return(-1);
    506 	}
    507 	if ((of = Fopen(name, "w")) == NULL) {
    508 		perror(name);
    509 		return(-1);
    510 	}
    511 	lc = 0;
    512 	cc = 0;
    513 	while ((c = getc(fp)) != EOF) {
    514 		cc++;
    515 		if (c == '\n')
    516 			lc++;
    517 		(void) putc(c, of);
    518 		if (ferror(of)) {
    519 			perror(name);
    520 			Fclose(of);
    521 			return(-1);
    522 		}
    523 	}
    524 	Fclose(of);
    525 	printf("%d/%ld\n", lc, cc);
    526 	fflush(stdout);
    527 	return(0);
    528 }
    529 
    530 /*
    531  * Edit the message being collected on fp.
    532  * On return, make the edit file the new temp file.
    533  */
    534 void
    535 mesedit(FILE *fp, int c)
    536 {
    537 	sig_t sigint = signal(SIGINT, SIG_IGN);
    538 	FILE *nf = run_editor(fp, (off_t)-1, c, 0);
    539 
    540 	if (nf != NULL) {
    541 		fseek(nf, 0L, 2);
    542 		collf = nf;
    543 		Fclose(fp);
    544 	}
    545 	(void) signal(SIGINT, sigint);
    546 }
    547 
    548 /*
    549  * Pipe the message through the command.
    550  * Old message is on stdin of command;
    551  * New message collected from stdout.
    552  * Sh -c must return 0 to accept the new message.
    553  */
    554 void
    555 mespipe(FILE *fp, char cmd[])
    556 {
    557 	FILE *nf;
    558 	sig_t sigint = signal(SIGINT, SIG_IGN);
    559 	char *shellcmd;
    560 
    561 	if ((nf = Fopen(tempEdit, "w+")) == NULL) {
    562 		perror(tempEdit);
    563 		goto out;
    564 	}
    565 	(void) unlink(tempEdit);
    566 	/*
    567 	 * stdin = current message.
    568 	 * stdout = new message.
    569 	 */
    570 	if ((shellcmd = value("SHELL")) == NULL)
    571 		shellcmd = _PATH_CSHELL;
    572 	if (run_command(shellcmd,
    573 	    0, fileno(fp), fileno(nf), "-c", cmd, NULL) < 0) {
    574 		(void) Fclose(nf);
    575 		goto out;
    576 	}
    577 	if (fsize(nf) == 0) {
    578 		fprintf(stderr, "No bytes from \"%s\" !?\n", cmd);
    579 		(void) Fclose(nf);
    580 		goto out;
    581 	}
    582 	/*
    583 	 * Take new files.
    584 	 */
    585 	(void) fseek(nf, 0L, 2);
    586 	collf = nf;
    587 	(void) Fclose(fp);
    588 out:
    589 	(void) signal(SIGINT, sigint);
    590 }
    591 
    592 /*
    593  * Interpolate the named messages into the current
    594  * message, preceding each line with a tab.
    595  * Return a count of the number of characters now in
    596  * the message, or -1 if an error is encountered writing
    597  * the message temporary.  The flag argument is 'm' if we
    598  * should shift over and 'f' if not.
    599  */
    600 int
    601 forward(char ms[], FILE *fp, int f)
    602 {
    603 	int *msgvec;
    604 	struct ignoretab *ig;
    605 	char *tabst;
    606 
    607 	msgvec = (int *) salloc((msgCount+1) * sizeof *msgvec);
    608 	if (msgvec == (int *) NULL)
    609 		return(0);
    610 	if (getmsglist(ms, msgvec, 0) < 0)
    611 		return(0);
    612 	if (*msgvec == 0) {
    613 		*msgvec = first(0, MMNORM);
    614 		if (*msgvec == 0) {
    615 			printf("No appropriate messages\n");
    616 			return(0);
    617 		}
    618 		msgvec[1] = 0;
    619 	}
    620 	if (f == 'f' || f == 'F')
    621 		tabst = NULL;
    622 	else if ((tabst = value("indentprefix")) == NULL)
    623 		tabst = "\t";
    624 	ig = isupper(f) ? NULL : ignore;
    625 	printf("Interpolating:");
    626 	for (; *msgvec != 0; msgvec++) {
    627 		struct message *mp = message + *msgvec - 1;
    628 
    629 		touch(mp);
    630 		printf(" %d", *msgvec);
    631 		if (sendmessage(mp, fp, ig, tabst) < 0) {
    632 			perror(tempMail);
    633 			return(-1);
    634 		}
    635 	}
    636 	printf("\n");
    637 	return(0);
    638 }
    639 
    640 /*
    641  * Print (continue) when continued after ^Z.
    642  */
    643 /*ARGSUSED*/
    644 void
    645 collstop(int s)
    646 {
    647 	sig_t old_action = signal(s, SIG_DFL);
    648 	sigset_t nset;
    649 
    650 	sigemptyset(&nset);
    651 	sigaddset(&nset, s);
    652 	sigprocmask(SIG_UNBLOCK, &nset, NULL);
    653 	kill(0, s);
    654 	sigprocmask(SIG_BLOCK, &nset, NULL);
    655 	signal(s, old_action);
    656 	if (colljmp_p) {
    657 		colljmp_p = 0;
    658 		hadintr = 0;
    659 		longjmp(colljmp, 1);
    660 	}
    661 }
    662 
    663 /*
    664  * On interrupt, come here to save the partial message in ~/dead.letter.
    665  * Then jump out of the collection loop.
    666  */
    667 /*ARGSUSED*/
    668 void
    669 collint(int s)
    670 {
    671 	/*
    672 	 * the control flow is subtle, because we can be called from ~q.
    673 	 */
    674 	if (!hadintr) {
    675 		if (value("ignore") != NULL) {
    676 			puts("@");
    677 			fflush(stdout);
    678 			clearerr(stdin);
    679 			return;
    680 		}
    681 		hadintr = 1;
    682 		longjmp(colljmp, 1);
    683 	}
    684 	rewind(collf);
    685 	if (value("nosave") == NULL)
    686 		savedeadletter(collf);
    687 	longjmp(collabort, 1);
    688 }
    689 
    690 /*ARGSUSED*/
    691 void
    692 collhup(int s)
    693 {
    694 	rewind(collf);
    695 	savedeadletter(collf);
    696 	/*
    697 	 * Let's pretend nobody else wants to clean up,
    698 	 * a true statement at this time.
    699 	 */
    700 	exit(1);
    701 }
    702 
    703 void
    704 savedeadletter(FILE *fp)
    705 {
    706 	FILE *dbuf;
    707 	int c;
    708 	char *cp;
    709 
    710 	if (fsize(fp) == 0)
    711 		return;
    712 	cp = getdeadletter();
    713 	c = umask(077);
    714 	dbuf = Fopen(cp, "a");
    715 	(void) umask(c);
    716 	if (dbuf == NULL)
    717 		return;
    718 	while ((c = getc(fp)) != EOF)
    719 		(void) putc(c, dbuf);
    720 	Fclose(dbuf);
    721 	rewind(fp);
    722 }
    723