appl/popper/pop_updt.c

   1 /*
   2  * Copyright (c) 1989 Regents of the University of California.
   3  * All rights reserved.  The Berkeley software License Agreement
   4  * specifies the terms and conditions for redistribution.
   5  */
   6
   7 #include <popper.h>
   8 RCSID("$Id$");
   9
  10 static char standard_error[] =
  11     "Error error updating primary drop. Mailbox unchanged";
  12
  13 /*
  14  *  updt:   Apply changes to a user's POP maildrop
  15  */
  16
  17 int
  18 pop_updt (POP *p)
  19 {
  20     FILE                *   md;                     /*  Stream pointer for
  21                                                         the user's maildrop */
  22     int                     mfd;                    /*  File descriptor for
  23                                                         above */
  24     char                    buffer[BUFSIZ];         /*  Read buffer */
  25
  26     MsgInfoList         *   mp;                     /*  Pointer to message
  27                                                         info list */
  28     int                     msg_num;                /*  Current message
  29                                                         counter */
  30     int                     status_written;         /*  Status header field
  31                                                         written */
  32     int                     nchar;                  /* Bytes read/written */
  33
  34     long                    offset;                 /* New mail offset */
  35
  36     int                     blank_line;
  37
  38 #ifdef DEBUG
  39     if (p->debug) {
  40         pop_log(p,POP_DEBUG,"Performing maildrop update...");
  41         pop_log(p,POP_DEBUG,"Checking to see if all messages were deleted");
  42     }
  43 #endif /* DEBUG */
  44
  45     if(IS_MAILDIR(p))
  46         return pop_maildir_update(p);
  47
  48     if (p->msgs_deleted == p->msg_count) {
  49         /* Truncate before close, to avoid race condition,  DO NOT UNLINK!
  50            Another process may have opened,  and not yet tried to lock */
  51         ftruncate ((int)fileno(p->drop),0);
  52         fclose(p->drop) ;
  53         return (POP_SUCCESS);
  54     }
  55
  56 #ifdef DEBUG
  57     if (p->debug)
  58         pop_log(p,POP_DEBUG,"Opening mail drop \"%s\"",p->drop_name);
  59 #endif /* DEBUG */
  60
  61     /*  Open the user's real maildrop */
  62     if ((mfd = open(p->drop_name,O_RDWR|O_CREAT,0600)) == -1 ||
  63         (md = fdopen(mfd,"r+")) == NULL) {
  64         return pop_msg(p,POP_FAILURE,standard_error);
  65     }
  66
  67     /*  Lock the user's real mail drop */
  68     if ( flock(mfd, LOCK_EX) == -1 ) {
  69         fclose(md) ;
  70         return pop_msg(p,POP_FAILURE, "flock: '%s': %s", p->temp_drop,
  71                        strerror(errno));
  72     }
  73
  74     /* Go to the right places */
  75     offset = lseek((int)fileno(p->drop),0,SEEK_END) ;
  76
  77     /*  Append any messages that may have arrived during the session
  78         to the temporary maildrop */
  79     while ((nchar=read(mfd,buffer,BUFSIZ)) > 0)
  80         if ( nchar != write((int)fileno(p->drop),buffer,nchar) ) {
  81             nchar = -1;
  82             break ;
  83         }
  84     if ( nchar != 0 ) {
  85         fclose(md) ;
  86         ftruncate((int)fileno(p->drop),(int)offset) ;
  87         fclose(p->drop) ;
  88         return pop_msg(p,POP_FAILURE,standard_error);
  89     }
  90
  91     rewind(md);
  92     lseek(mfd,0,SEEK_SET);
  93     ftruncate(mfd,0) ;
  94
  95     /* Synch stdio and the kernel for the POP drop */
  96     rewind(p->drop);
  97     lseek((int)fileno(p->drop),0,SEEK_SET);
  98
  99     /*  Transfer messages not flagged for deletion from the temporary
 100         maildrop to the new maildrop */
 101 #ifdef DEBUG
 102     if (p->debug)
 103         pop_log(p,POP_DEBUG,"Creating new maildrop \"%s\" from \"%s\"",
 104                 p->drop_name,p->temp_drop);
 105 #endif /* DEBUG */
 106
 107     for (msg_num = 0; msg_num < p->msg_count; ++msg_num) {
 108
 109         int doing_body;
 110
 111         /*  Get a pointer to the message information list */
 112         mp = &p->mlp[msg_num];
 113
 114         if (mp->flags & DEL_FLAG) {
 115 #ifdef DEBUG
 116             if(p->debug)
 117                 pop_log(p,POP_DEBUG,
 118                     "Message %d flagged for deletion.",mp->number);
 119 #endif /* DEBUG */
 120             continue;
 121         }
 122
 123         fseek(p->drop,mp->offset,0);
 124
 125 #ifdef DEBUG
 126         if(p->debug)
 127             pop_log(p,POP_DEBUG,"Copying message %d.",mp->number);
 128 #endif /* DEBUG */
 129         blank_line = 1;
 130         for(status_written = doing_body = 0 ;
 131             fgets(buffer,MAXMSGLINELEN,p->drop);) {
 132
 133             if (doing_body == 0) { /* Header */
 134
 135                 /*  Update the message status */
 136                 if (strncasecmp(buffer,"Status:",7) == 0) {
 137                     if (mp->flags & RETR_FLAG)
 138                         fputs("Status: RO\n",md);
 139                     else
 140                         fputs(buffer, md);
 141                     status_written++;
 142                     continue;
 143                 }
 144                 /*  A blank line signals the end of the header. */
 145                 if (*buffer == '\n') {
 146                     doing_body = 1;
 147                     if (status_written == 0) {
 148                         if (mp->flags & RETR_FLAG)
 149                             fputs("Status: RO\n\n",md);
 150                         else
 151                             fputs("Status: U\n\n",md);
 152                     }
 153                     else fputs ("\n", md);
 154                     continue;
 155                 }
 156                 /*  Save another header line */
 157                 fputs (buffer, md);
 158             }
 159             else { /* Body */
 160                 if (blank_line && strncmp(buffer,"From ",5) == 0) break;
 161                 fputs (buffer, md);
 162                 blank_line = (*buffer == '\n');
 163             }
 164         }
 165     }
 166
 167     /* flush and check for errors now!  The new mail will writen
 168        without stdio,  since we need not separate messages */
 169
 170     fflush(md) ;
 171     if (ferror(md)) {
 172         ftruncate(mfd,0) ;
 173         fclose(md) ;
 174         fclose(p->drop) ;
 175         return pop_msg(p,POP_FAILURE,standard_error);
 176     }
 177
 178     /* Go to start of new mail if any */
 179     lseek((int)fileno(p->drop),offset,SEEK_SET);
 180
 181     while((nchar=read((int)fileno(p->drop),buffer,BUFSIZ)) > 0)
 182         if ( nchar != write(mfd,buffer,nchar) ) {
 183             nchar = -1;
 184             break ;
 185         }
 186     if ( nchar != 0 ) {
 187         ftruncate(mfd,0) ;
 188         fclose(md) ;
 189         fclose(p->drop) ;
 190         return pop_msg(p,POP_FAILURE,standard_error);
 191     }
 192
 193     /*  Close the maildrop and empty temporary maildrop */
 194     fclose(md);
 195     ftruncate((int)fileno(p->drop),0);
 196     fclose(p->drop);
 197
 198     return(pop_quit(p));
 199 }