usr.bin/mail/collect.c

   1 /*
   2  * Copyright (c) 1980, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. Neither the name of the University nor the names of its contributors
  14  *    may be used to endorse or promote products derived from this software
  15  *    without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  *
  29  * @(#)collect.c        8.2 (Berkeley) 4/19/94
  30  * $FreeBSD: src/usr.bin/mail/collect.c,v 1.4.6.3 2003/01/06 05:46:03 mikeh Exp $
  31  * $DragonFly: src/usr.bin/mail/collect.c,v 1.4 2004/09/08 03:01:11 joerg Exp $
  32  */
  33
  34 /*
  35  * Mail -- a mail program
  36  *
  37  * Collect input from standard input, handling
  38  * ~ escapes.
  39  */
  40
  41 #include "rcv.h"
  42 #include <fcntl.h>
  43 #include "extern.h"
  44
  45 /*
  46  * Read a message from standard output and return a read file to it
  47  * or NULL on error.
  48  */
  49
  50 /*
  51  * The following hokiness with global variables is so that on
  52  * receipt of an interrupt signal, the partial message can be salted
  53  * away on dead.letter.
  54  */
  55
  56 static  sig_t   saveint;                /* Previous SIGINT value */
  57 static  sig_t   savehup;                /* Previous SIGHUP value */
  58 static  sig_t   savetstp;               /* Previous SIGTSTP value */
  59 static  sig_t   savettou;               /* Previous SIGTTOU value */
  60 static  sig_t   savettin;               /* Previous SIGTTIN value */
  61 static  FILE    *collf;                 /* File for saving away */
  62 static  int     hadintr;                /* Have seen one SIGINT so far */
  63
  64 static  jmp_buf colljmp;                /* To get back to work */
  65 static  int     colljmp_p;              /* whether to long jump */
  66 static  jmp_buf collabort;              /* To end collection with error */
  67
  68 FILE *
  69 collect(struct header *hp, int printheaders)
  70 {
  71         FILE *fbuf;
  72         int lc, cc, escape, eofcount, fd, c, t;
  73         char linebuf[LINESIZE], tempname[PATHSIZE], *cp, getsub;
  74         sigset_t nset;
  75         int longline, lastlong, rc;     /* So we don't make 2 or more lines
  76                                            out of a long input line. */
  77
  78         collf = NULL;
  79         /*
  80          * Start catching signals from here, but we're still die on interrupts
  81          * until we're in the main loop.
  82          */
  83         sigemptyset(&nset);
  84         sigaddset(&nset, SIGINT);
  85         sigaddset(&nset, SIGHUP);
  86         sigprocmask(SIG_BLOCK, &nset, NULL);
  87         if ((saveint = signal(SIGINT, SIG_IGN)) != SIG_IGN)
  88                 signal(SIGINT, collint);
  89         if ((savehup = signal(SIGHUP, SIG_IGN)) != SIG_IGN)
  90                 signal(SIGHUP, collhup);
  91         savetstp = signal(SIGTSTP, collstop);
  92         savettou = signal(SIGTTOU, collstop);
  93         savettin = signal(SIGTTIN, collstop);
  94         if (setjmp(collabort) || setjmp(colljmp)) {
  95                 rm(tempname);
  96                 goto err;
  97         }
  98         sigprocmask(SIG_UNBLOCK, &nset, NULL);
  99
 100         noreset++;
 101         snprintf(tempname, sizeof(tempname), "%s/mail.RsXXXXXXXXXX", tmpdir);
 102         if ((fd = mkstemp(tempname)) == -1 ||
 103             (collf = Fdopen(fd, "w+")) == NULL) {
 104                 warn("%s", tempname);
 105                 goto err;
 106         }
 107         rm(tempname);
 108
 109         /*
 110          * If we are going to prompt for a subject,
 111          * refrain from printing a newline after
 112          * the headers (since some people mind).
 113          */
 114         t = GTO|GSUBJECT|GCC|GNL;
 115         getsub = 0;
 116         if (hp->h_subject == NULL && value("interactive") != NULL &&
 117             (value("ask") != NULL || value("asksub") != NULL))
 118                 t &= ~GNL, getsub++;
 119         if (printheaders) {
 120                 puthead(hp, stdout, t);
 121                 fflush(stdout);
 122         }
 123         if ((cp = value("escape")) != NULL)
 124                 escape = *cp;
 125         else
 126                 escape = ESCAPE;
 127         eofcount = 0;
 128         hadintr = 0;
 129         lastlong = 0;
 130         longline = 0;
 131
 132         if (!setjmp(colljmp)) {
 133                 if (getsub)
 134                         grabh(hp, GSUBJECT);
 135         } else {
 136                 /*
 137                  * Come here for printing the after-signal message.
 138                  * Duplicate messages won't be printed because
 139                  * the write is aborted if we get a SIGTTOU.
 140                  */
 141 cont:
 142                 if (hadintr) {
 143                         fflush(stdout);
 144                         fprintf(stderr,
 145                         "\n(Interrupt -- one more to kill letter)\n");
 146                 } else {
 147                         printf("(continue)\n");
 148                         fflush(stdout);
 149                 }
 150         }
 151         for (;;) {
 152                 colljmp_p = 1;
 153                 c = readline(stdin, linebuf, LINESIZE);
 154                 colljmp_p = 0;
 155                 if (c < 0) {
 156                         if (value("interactive") != NULL &&
 157                             value("ignoreeof") != NULL && ++eofcount < 25) {
 158                                 printf("Use \".\" to terminate letter\n");
 159                                 continue;
 160                         }
 161                         break;
 162                 }
 163                 lastlong = longline;
 164                 longline = c == LINESIZE - 1;
 165                 eofcount = 0;
 166                 hadintr = 0;
 167                 if (linebuf[0] == '.' && linebuf[1] == '\0' &&
 168                     value("interactive") != NULL && !lastlong &&
 169                     (value("dot") != NULL || value("ignoreeof") != NULL))
 170                         break;
 171                 if (linebuf[0] != escape || value("interactive") == NULL ||
 172                     lastlong) {
 173                         if (putline(collf, linebuf, !longline) < 0)
 174                                 goto err;
 175                         continue;
 176                 }
 177                 c = linebuf[1];
 178                 switch (c) {
 179                 default:
 180                         /*
 181                          * On double escape, just send the single one.
 182                          * Otherwise, it's an error.
 183                          */
 184                         if (c == escape) {
 185                                 if (putline(collf, &linebuf[1], !longline) < 0)
 186                                         goto err;
 187                                 else
 188                                         break;
 189                         }
 190                         printf("Unknown tilde escape.\n");
 191                         break;
 192                 case 'C':
 193                         /*
 194                          * Dump core.
 195                          */
 196                         core();
 197                         break;
 198                 case '!':
 199                         /*
 200                          * Shell escape, send the balance of the
 201                          * line to sh -c.
 202                          */
 203                         shell(&linebuf[2]);
 204                         break;
 205                 case ':':
 206                 case '_':
 207                         /*
 208                          * Escape to command mode, but be nice!
 209                          */
 210                         execute(&linebuf[2], 1);
 211                         goto cont;
 212                 case '.':
 213                         /*
 214                          * Simulate end of file on input.
 215                          */
 216                         goto out;
 217                 case 'q':
 218                         /*
 219                          * Force a quit of sending mail.
 220                          * Act like an interrupt happened.
 221                          */
 222                         hadintr++;
 223                         collint(SIGINT);
 224                         exit(1);
 225                 case 'x':
 226                         /*
 227                          * Exit, do not save in dead.letter.
 228                          */
 229                         goto err;
 230                 case 'h':
 231                         /*
 232                          * Grab a bunch of headers.
 233                          */
 234                         grabh(hp, GTO|GSUBJECT|GCC|GBCC);
 235                         goto cont;
 236                 case 't':
 237                         /*
 238                          * Add to the To list.
 239                          */
 240                         hp->h_to = cat(hp->h_to, extract(&linebuf[2], GTO));
 241                         break;
 242                 case 's':
 243                         /*
 244                          * Set the Subject line.
 245                          */
 246                         cp = &linebuf[2];
 247                         while (isspace((unsigned char)*cp))
 248                                 cp++;
 249                         hp->h_subject = savestr(cp);
 250                         break;
 251                 case 'R':
 252                         /*
 253                          * Set the Reply-To line.
 254                          */
 255                         cp = &linebuf[2];
 256                         while (isspace((unsigned char)*cp))
 257                                 cp++;
 258                         hp->h_replyto = savestr(cp);
 259                         break;
 260                 case 'c':
 261                         /*
 262                          * Add to the CC list.
 263                          */
 264                         hp->h_cc = cat(hp->h_cc, extract(&linebuf[2], GCC));
 265                         break;
 266                 case 'b':
 267                         /*
 268                          * Add to the BCC list.
 269                          */
 270                         hp->h_bcc = cat(hp->h_bcc, extract(&linebuf[2], GBCC));
 271                         break;
 272                 case 'i':
 273                 case 'A':
 274                 case 'a':
 275                         /*
 276                          * Insert named variable in message.
 277                          */
 278                         switch(c) {
 279                                 case 'i':
 280                                         cp = &linebuf[2];
 281                                         while(isspace((unsigned char)*cp))
 282                                                 cp++;
 283                                         break;
 284                                 case 'a':
 285                                         cp = "sign";
 286                                         break;
 287                                 case 'A':
 288                                         cp = "Sign";
 289                                         break;
 290                                 default:
 291                                         goto err;
 292                         }
 293
 294                         if(*cp != '\0' && (cp = value(cp)) != NULL) {
 295                                 printf("%s\n", cp);
 296                                 if(putline(collf, cp, 1) < 0)
 297                                         goto err;
 298                         }
 299
 300                         break;
 301                 case 'd':
 302                         /*
 303                          * Read in the dead letter file.
 304                          */
 305                         if (strlcpy(linebuf + 2, getdeadletter(),
 306                                 sizeof(linebuf) - 2)
 307                             >= sizeof(linebuf) - 2) {
 308                                 printf("Line buffer overflow\n");
 309                                 break;
 310                         }
 311                         /* FALLTHROUGH */
 312                 case 'r':
 313                 case '<':
 314                         /*
 315                          * Invoke a file:
 316                          * Search for the file name,
 317                          * then open it and copy the contents to collf.
 318                          */
 319                         cp = &linebuf[2];
 320                         while (isspace((unsigned char)*cp))
 321                                 cp++;
 322                         if (*cp == '\0') {
 323                                 printf("Interpolate what file?\n");
 324                                 break;
 325                         }
 326                         cp = expand(cp);
 327                         if (cp == NULL)
 328                                 break;
 329                         if (*cp == '!') {
 330                                 /*
 331                                  * Insert stdout of command.
 332                                  */
 333                                 char *sh;
 334                                 int nullfd, tempfd, rc;
 335                                 char tempname2[PATHSIZE];
 336
 337                                 if ((nullfd = open("/dev/null", O_RDONLY, 0))
 338                                     == -1) {
 339                                         warn("/dev/null");
 340                                         break;
 341                                 }
 342
 343                                 snprintf(tempname2, sizeof(tempname2),
 344                                          "%s/mail.ReXXXXXXXXXX", tmpdir);
 345                                 if ((tempfd = mkstemp(tempname2)) == -1 ||
 346                                     (fbuf = Fdopen(tempfd, "w+")) == NULL) {
 347                                         warn("%s", tempname2);
 348                                         break;
 349                                 }
 350                                 unlink(tempname2);
 351
 352                                 if ((sh = value("SHELL")) == NULL)
 353                                         sh = _PATH_CSHELL;
 354
 355                                 rc = run_command(sh, 0, nullfd, fileno(fbuf),
 356                                     "-c", cp+1, NULL);
 357
 358                                 close(nullfd);
 359
 360                                 if (rc < 0) {
 361                                         Fclose(fbuf);
 362                                         break;
 363                                 }
 364
 365                                 if (fsize(fbuf) == 0) {
 366                                         fprintf(stderr,
 367                                             "No bytes from command \"%s\"\n",
 368                                             cp+1);
 369                                         Fclose(fbuf);
 370                                         break;
 371                                 }
 372
 373                                 rewind(fbuf);
 374                         } else if (isdir(cp)) {
 375                                 printf("%s: Directory\n", cp);
 376                                 break;
 377                         } else if ((fbuf = Fopen(cp, "r")) == NULL) {
 378                                 warn("%s", cp);
 379                                 break;
 380                         }
 381                         printf("\"%s\" ", cp);
 382                         fflush(stdout);
 383                         lc = 0;
 384                         cc = 0;
 385                         while ((rc = readline(fbuf, linebuf, LINESIZE)) >= 0) {
 386                                 if (rc != LINESIZE - 1)
 387                                         lc++;
 388                                 if ((t = putline(collf, linebuf,
 389                                          rc != LINESIZE - 1)) < 0) {
 390                                         Fclose(fbuf);
 391                                         goto err;
 392                                 }
 393                                 cc += t;
 394                         }
 395                         Fclose(fbuf);
 396                         printf("%d/%d\n", lc, cc);
 397                         break;
 398                 case 'w':
 399                         /*
 400                          * Write the message on a file.
 401                          */
 402                         cp = &linebuf[2];
 403                         while (*cp == ' ' || *cp == '\t')
 404                                 cp++;
 405                         if (*cp == '\0') {
 406                                 fprintf(stderr, "Write what file!?\n");
 407                                 break;
 408                         }
 409                         if ((cp = expand(cp)) == NULL)
 410                                 break;
 411                         rewind(collf);
 412                         exwrite(cp, collf, 1);
 413                         break;
 414                 case 'm':
 415                 case 'M':
 416                 case 'f':
 417                 case 'F':
 418                         /*
 419                          * Interpolate the named messages, if we
 420                          * are in receiving mail mode.  Does the
 421                          * standard list processing garbage.
 422                          * If ~f is given, we don't shift over.
 423                          */
 424                         if (forward(linebuf + 2, collf, tempname, c) < 0)
 425                                 goto err;
 426                         goto cont;
 427                 case '?':
 428                         if ((fbuf = Fopen(_PATH_TILDE, "r")) == NULL) {
 429                                 warn("%s", _PATH_TILDE);
 430                                 break;
 431                         }
 432                         while ((t = getc(fbuf)) != EOF)
 433                                 putchar(t);
 434                         Fclose(fbuf);
 435                         break;
 436                 case 'p':
 437                         /*
 438                          * Print out the current state of the
 439                          * message without altering anything.
 440                          */
 441                         rewind(collf);
 442                         printf("-------\nMessage contains:\n");
 443                         puthead(hp, stdout, GTO|GSUBJECT|GCC|GBCC|GNL);
 444                         while ((t = getc(collf)) != EOF)
 445                                 putchar(t);
 446                         goto cont;
 447                 case '|':
 448                         /*
 449                          * Pipe message through command.
 450                          * Collect output as new message.
 451                          */
 452                         rewind(collf);
 453                         mespipe(collf, &linebuf[2]);
 454                         goto cont;
 455                 case 'v':
 456                 case 'e':
 457                         /*
 458                          * Edit the current message.
 459                          * 'e' means to use EDITOR
 460                          * 'v' means to use VISUAL
 461                          */
 462                         rewind(collf);
 463                         mesedit(collf, c);
 464                         goto cont;
 465                 }
 466         }
 467         goto out;
 468 err:
 469         if (collf != NULL) {
 470                 Fclose(collf);
 471                 collf = NULL;
 472         }
 473 out:
 474         if (collf != NULL)
 475                 rewind(collf);
 476         noreset--;
 477         sigprocmask(SIG_BLOCK, &nset, NULL);
 478         signal(SIGINT, saveint);
 479         signal(SIGHUP, savehup);
 480         signal(SIGTSTP, savetstp);
 481         signal(SIGTTOU, savettou);
 482         signal(SIGTTIN, savettin);
 483         sigprocmask(SIG_UNBLOCK, &nset, NULL);
 484         return (collf);
 485 }
 486
 487 /*
 488  * Write a file, ex-like if f set.
 489  */
 490 int
 491 exwrite(char *name, FILE *fp, int f)
 492 {
 493         FILE *of;
 494         int c, lc;
 495         long cc;
 496         struct stat junk;
 497
 498         if (f) {
 499                 printf("\"%s\" ", name);
 500                 fflush(stdout);
 501         }
 502         if (stat(name, &junk) >= 0 && S_ISREG(junk.st_mode)) {
 503                 if (!f)
 504                         fprintf(stderr, "%s: ", name);
 505                 fprintf(stderr, "File exists\n");
 506                 return (-1);
 507         }
 508         if ((of = Fopen(name, "w")) == NULL) {
 509                 warn(NULL);
 510                 return (-1);
 511         }
 512         lc = 0;
 513         cc = 0;
 514         while ((c = getc(fp)) != EOF) {
 515                 cc++;
 516                 if (c == '\n')
 517                         lc++;
 518                 putc(c, of);
 519                 if (ferror(of)) {
 520                         warnx("%s", name);
 521                         Fclose(of);
 522                         return (-1);
 523                 }
 524         }
 525         Fclose(of);
 526         printf("%d/%ld\n", lc, cc);
 527         fflush(stdout);
 528         return (0);
 529 }
 530
 531 /*
 532  * Edit the message being collected on fp.
 533  * On return, make the edit file the new temp file.
 534  */
 535 void
 536 mesedit(FILE *fp, int c)
 537 {
 538         sig_t sigint = signal(SIGINT, SIG_IGN);
 539         FILE *nf = run_editor(fp, (off_t)-1, c, 0);
 540
 541         if (nf != NULL) {
 542                 fseeko(nf, (off_t)0, SEEK_END);
 543                 collf = nf;
 544                 Fclose(fp);
 545         }
 546         signal(SIGINT, sigint);
 547 }
 548
 549 /*
 550  * Pipe the message through the command.
 551  * Old message is on stdin of command;
 552  * New message collected from stdout.
 553  * Sh -c must return 0 to accept the new message.
 554  */
 555 void
 556 mespipe(FILE *fp, char *cmd)
 557 {
 558         FILE *nf;
 559         int fd;
 560         sig_t sigint = signal(SIGINT, SIG_IGN);
 561         char *sh, tempname[PATHSIZE];
 562
 563         snprintf(tempname, sizeof(tempname), "%s/mail.ReXXXXXXXXXX", tmpdir);
 564         if ((fd = mkstemp(tempname)) == -1 ||
 565             (nf = Fdopen(fd, "w+")) == NULL) {
 566                 warn("%s", tempname);
 567                 goto out;
 568         }
 569         rm(tempname);
 570         /*
 571          * stdin = current message.
 572          * stdout = new message.
 573          */
 574         if ((sh = value("SHELL")) == NULL)
 575                 sh = _PATH_CSHELL;
 576         if (run_command(sh, 0, fileno(fp), fileno(nf), "-c", cmd, NULL) < 0) {
 577                 Fclose(nf);
 578                 goto out;
 579         }
 580         if (fsize(nf) == 0) {
 581                 fprintf(stderr, "No bytes from \"%s\" !?\n", cmd);
 582                 Fclose(nf);
 583                 goto out;
 584         }
 585         /*
 586          * Take new files.
 587          */
 588         fseeko(nf, (off_t)0, SEEK_END);
 589         collf = nf;
 590         Fclose(fp);
 591 out:
 592         signal(SIGINT, sigint);
 593 }
 594
 595 /*
 596  * Interpolate the named messages into the current
 597  * message, preceding each line with a tab.
 598  * Return a count of the number of characters now in
 599  * the message, or -1 if an error is encountered writing
 600  * the message temporary.  The flag argument is 'm' if we
 601  * should shift over and 'f' if not.
 602  */
 603 int
 604 forward(char *ms, FILE *fp, char *fn, int f)
 605 {
 606         int *msgvec;
 607         struct ignoretab *ig;
 608         char *tabst;
 609
 610         msgvec = (int *)salloc((msgCount+1) * sizeof(*msgvec));
 611         if (msgvec == NULL)
 612                 return (0);
 613         if (getmsglist(ms, msgvec, 0) < 0)
 614                 return (0);
 615         if (*msgvec == 0) {
 616                 *msgvec = first(0, MMNORM);
 617                 if (*msgvec == 0) {
 618                         printf("No appropriate messages\n");
 619                         return (0);
 620                 }
 621                 msgvec[1] = 0;
 622         }
 623         if (f == 'f' || f == 'F')
 624                 tabst = NULL;
 625         else if ((tabst = value("indentprefix")) == NULL)
 626                 tabst = "\t";
 627         ig = isupper((unsigned char)f) ? NULL : ignore;
 628         printf("Interpolating:");
 629         for (; *msgvec != 0; msgvec++) {
 630                 struct message *mp = message + *msgvec - 1;
 631
 632                 touch(mp);
 633                 printf(" %d", *msgvec);
 634                 if (sendmessage(mp, fp, ig, tabst) < 0) {
 635                         warnx("%s", fn);
 636                         return (-1);
 637                 }
 638         }
 639         printf("\n");
 640         return (0);
 641 }
 642
 643 /*
 644  * Print (continue) when continued after ^Z.
 645  */
 646 /*ARGSUSED*/
 647 void
 648 collstop(int s)
 649 {
 650         sig_t old_action = signal(s, SIG_DFL);
 651         sigset_t nset;
 652
 653         sigemptyset(&nset);
 654         sigaddset(&nset, s);
 655         sigprocmask(SIG_UNBLOCK, &nset, NULL);
 656         kill(0, s);
 657         sigprocmask(SIG_BLOCK, &nset, NULL);
 658         signal(s, old_action);
 659         if (colljmp_p) {
 660                 colljmp_p = 0;
 661                 hadintr = 0;
 662                 longjmp(colljmp, 1);
 663         }
 664 }
 665
 666 /*
 667  * On interrupt, come here to save the partial message in ~/dead.letter.
 668  * Then jump out of the collection loop.
 669  */
 670 /*ARGSUSED*/
 671 void
 672 collint(int s)
 673 {
 674         /*
 675          * the control flow is subtle, because we can be called from ~q.
 676          */
 677         if (!hadintr) {
 678                 if (value("ignore") != NULL) {
 679                         printf("@");
 680                         fflush(stdout);
 681                         clearerr(stdin);
 682                         return;
 683                 }
 684                 hadintr = 1;
 685                 longjmp(colljmp, 1);
 686         }
 687         rewind(collf);
 688         if (value("nosave") == NULL)
 689                 savedeadletter(collf);
 690         longjmp(collabort, 1);
 691 }
 692
 693 /*ARGSUSED*/
 694 void
 695 collhup(int s)
 696 {
 697         rewind(collf);
 698         savedeadletter(collf);
 699         /*
 700          * Let's pretend nobody else wants to clean up,
 701          * a true statement at this time.
 702          */
 703         exit(1);
 704 }
 705
 706 void
 707 savedeadletter(FILE *fp)
 708 {
 709         FILE *dbuf;
 710         int c;
 711         char *cp;
 712
 713         if (fsize(fp) == 0)
 714                 return;
 715         cp = getdeadletter();
 716         c = umask(077);
 717         dbuf = Fopen(cp, "a");
 718         umask(c);
 719         if (dbuf == NULL)
 720                 return;
 721         while ((c = getc(fp)) != EOF)
 722                 putc(c, dbuf);
 723         Fclose(dbuf);
 724         rewind(fp);
 725 }