usr/src/cmd/mail/copyback.c

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License, Version 1.0 only
   6  * (the "License").  You may not use this file except in compliance
   7  * with the License.
   8  *
   9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
  10  * or http://www.opensolaris.org/os/licensing.
  11  * See the License for the specific language governing permissions
  12  * and limitations under the License.
  13  *
  14  * When distributing Covered Code, include this CDDL HEADER in each
  15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  16  * If applicable, add the following below this CDDL HEADER, with the
  17  * fields enclosed by brackets "[]" replaced with your own identifying
  18  * information: Portions Copyright [yyyy] [name of copyright owner]
  19  *
  20  * CDDL HEADER END
  21  */
  22 /*      Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
  23 /*        All Rights Reserved   */
  24
  25 #pragma ident   "%Z%%M% %I%     %E% SMI"
  26
  27 /*
  28  *  NAME
  29  *      copyback - copy temp or whatever back to /var/mail
  30  *
  31  *  SYNOPSIS
  32  *      void copyback()
  33  *
  34  *  DESCRIPTION
  35  *      Copy the reduced contents of lettmp back to
  36  *      the mail file. First copy any new mail from
  37  *      the mail file to the end of lettmp.
  38  */
  39
  40 #include "mail.h"
  41 void
  42 copyback()
  43 {
  44         register int    i, n;
  45         int             new = 0;
  46         mode_t          mailmode, omask;
  47         struct stat     stbuf;
  48         void (*hstat)(), (*istat)(), (*qstat)();
  49
  50         istat = signal(SIGINT, SIG_IGN);
  51         qstat = signal(SIGQUIT, SIG_IGN);
  52         hstat = signal(SIGHUP, SIG_IGN);
  53         lock(my_name);
  54         stat(mailfile, &stbuf);
  55         mailmode = stbuf.st_mode;
  56
  57         /*
  58          *      Has new mail arrived?
  59          */
  60         if (stbuf.st_size != let[nlet].adr) {
  61                 malf = doopen(mailfile, "r", E_FILE);
  62                 fseek(malf, let[nlet].adr, 0);
  63                 fclose(tmpf);
  64                 tmpf = doopen(lettmp, "a", E_TMP);
  65                 /*
  66                  *      Append new mail assume only one new letter
  67                  */
  68                 if (!copystream(malf, tmpf)) {
  69                         fclose(malf);
  70                         tmperr();
  71                         done(0);
  72                 }
  73                 fclose(malf);
  74                 fclose(tmpf);
  75                 tmpf = doopen(lettmp, "r+", E_TMP);
  76                 if (nlet == (MAXLET-2)) {
  77                         errmsg(E_SPACE, "");
  78                         done(0);
  79                 }
  80                 let[++nlet].adr = stbuf.st_size;
  81                 new = 1;
  82         }
  83
  84         /*
  85          *      Copy mail back to mail file
  86          */
  87         omask = umask(0117);
  88
  89         /*
  90          *      The invoker must own the mailfile being copied to
  91          */
  92         if ((stbuf.st_uid != my_euid) && (stbuf.st_uid != my_uid)) {
  93                 errmsg(E_OWNR, "");
  94                 done(0);
  95         }
  96
  97         /*
  98          *      If user specified the '-f' option we dont do
  99          *      the routines to handle :saved files.
 100          *      As we would(incorrectly) restore to the user's
 101          *      mailfile upon next execution!
 102          */
 103         if (flgf) {
 104                 (void) strlcpy(savefile, mailfile, sizeof (savefile));
 105         } else {
 106                 cat(savefile, mailsave, my_name);
 107         }
 108
 109         if ((malf = fopen(savefile, "w")) == NULL) {
 110                 if (!flgf) {
 111                         errmsg(E_FILE, "Cannot open savefile");
 112                 } else {
 113                         errmsg(E_FILE, "Cannot re-write the alternate file");
 114                 }
 115                 done(0);
 116         }
 117
 118         if (chown(savefile, mf_uid, mf_gid) == -1) {
 119                 errmsg(E_FILE, "Cannot chown savefile");
 120                 done(0);
 121         }
 122         umask(omask);
 123         n = 0;
 124
 125         for (i = 0; i < nlet; i++) {
 126                 /*
 127                  *      Note: any action other than an undelete, or a
 128                  *      plain read causes the letter acted upon to be
 129                  *      deleted
 130                  */
 131                 if (let[i].change == ' ') {
 132                         if (copylet(i, malf, ORDINARY) == FALSE) {
 133                                 errmsg(E_FILE, "Cannot copy mail to savefile");
 134                                 (void) fprintf(stderr, "%s: A copy of your "
 135                                     "mailfile is in '%s'\n", program, lettmp);
 136                                 done(1);        /* keep temp file */
 137                         }
 138                         n++;
 139                 }
 140         }
 141         fclose(malf);
 142
 143         if (!flgf) {
 144                 if (unlink(mailfile) != 0) {
 145                         errmsg(E_FILE, "Cannot unlink mailfile");
 146                         done(0);
 147                 }
 148                 chmod(savefile, mailmode);
 149 #ifdef SVR4
 150                 if (rename(savefile, mailfile) != 0) {
 151                         errmsg(E_FILE, "Cannot rename savefile to mailfile");
 152                         done(0);
 153                 }
 154 #else
 155                 if (link(savefile, mailfile) != 0) {
 156                         errmsg(E_FILE, "Cannot link savefile to mailfile");
 157                         done(0);
 158                 }
 159                 if (unlink(savefile) != 0) {
 160                         errmsg(E_FILE, "Cannot unlink save file");
 161                         done(0);
 162                 }
 163 #endif
 164         }
 165
 166         /*
 167          *      Empty mailbox?
 168          */
 169         if (n == 0) {
 170                 delempty(stbuf.st_mode, mailfile);
 171         }
 172
 173         if (new && !flgf) {
 174                 printf("New mail arrived\n");
 175         }
 176
 177         unlock();
 178         (void) signal(SIGINT, istat);
 179         (void) signal(SIGQUIT, qstat);
 180         (void) signal(SIGHUP, hstat);
 181 }