lib-src/fakemail.c

   1 /* sendmail-like interface to /bin/mail for system V,
   2    Copyright (C) 1985, 1994 Free Software Foundation, Inc.
   3
   4 This file is part of GNU Emacs.
   5
   6 GNU Emacs is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2, or (at your option)
   9 any later version.
  10
  11 GNU Emacs is distributed in the hope that it will be useful,
  12 but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 GNU General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GNU Emacs; see the file COPYING.  If not, write to
  18 the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.  */
  19
  20
  21 #define NO_SHORTNAMES
  22 #include <../src/config.h>
  23
  24 #if defined (BSD) && !defined (BSD4_1) && !defined (USE_FAKEMAIL)
  25 /* This program isnot used in BSD, so just avoid loader complaints.  */
  26 void
  27 main ()
  28 {
  29 }
  30 #else /* not BSD 4.2 (or newer) */
  31 #ifdef MSDOS
  32 void
  33 main ()
  34 {
  35 }
  36 #else /* not MSDOS */
  37 /* This conditional contains all the rest of the file.  */
  38
  39 /* These are defined in config in some versions. */
  40
  41 #ifdef static
  42 #undef static
  43 #endif
  44
  45 #ifdef read
  46 #undef read
  47 #undef write
  48 #undef open
  49 #undef close
  50 #endif
  51
  52 #include <stdio.h>
  53 #include <string.h>
  54 #include <ctype.h>
  55 #include <time.h>
  56 #include <pwd.h>
  57 \f
  58 /* Type definitions */
  59
  60 #define boolean int
  61 #define true 1
  62 #define false 0
  63
  64 /* Various lists */
  65
  66 struct line_record
  67 {
  68   char *string;
  69   struct line_record *continuation;
  70 };
  71 typedef struct line_record *line_list;
  72
  73 struct header_record
  74 {
  75   line_list text;
  76   struct header_record *next;
  77   struct header_record *previous;
  78 };
  79 typedef struct header_record *header;
  80
  81 struct stream_record
  82 {
  83   FILE *handle;
  84   int (*action)();
  85   struct stream_record *rest_streams;
  86 };
  87 typedef struct stream_record *stream_list;
  88
  89 /* A `struct linebuffer' is a structure which holds a line of text.
  90  * `readline' reads a line from a stream into a linebuffer
  91  * and works regardless of the length of the line.
  92  */
  93
  94 struct linebuffer
  95 {
  96   long size;
  97   char *buffer;
  98 };
  99
 100 struct linebuffer lb;
 101
 102 #define new_list()                                      \
 103   ((line_list) xmalloc (sizeof (struct line_record)))
 104 #define new_header()                            \
 105   ((header) xmalloc (sizeof (struct header_record)))
 106 #define new_stream()                            \
 107   ((stream_list) xmalloc (sizeof (struct stream_record)))
 108 #define alloc_string(nchars)                            \
 109   ((char *) xmalloc ((nchars) + 1))
 110 \f
 111 /* Global declarations */
 112
 113 #define BUFLEN 1024
 114 #define KEYWORD_SIZE 256
 115 #define FROM_PREFIX "From"
 116 #define MY_NAME "fakemail"
 117 #define NIL ((line_list) NULL)
 118 #define INITIAL_LINE_SIZE 200
 119
 120 #ifndef MAIL_PROGRAM_NAME
 121 #define MAIL_PROGRAM_NAME "/bin/mail"
 122 #endif
 123
 124 static char *my_name;
 125 static char *the_date;
 126 static char *the_user;
 127 static line_list file_preface;
 128 static stream_list the_streams;
 129 static boolean no_problems = true;
 130
 131 extern FILE *popen ();
 132 extern int fclose (), pclose ();
 133
 134 #ifdef CURRENT_USER
 135 extern struct passwd *getpwuid ();
 136 extern unsigned short geteuid ();
 137 static struct passwd *my_entry;
 138 #define cuserid(s)                              \
 139 (my_entry = getpwuid (((int) geteuid ())),      \
 140  my_entry->pw_name)
 141 #endif
 142 \f
 143 /* Utilities */
 144
 145 /* Print error message.  `s1' is printf control string, `s2' is arg for it. */
 146
 147 static void
 148 error (s1, s2)
 149      char *s1, *s2;
 150 {
 151   printf ("%s: ", my_name);
 152   printf (s1, s2);
 153   printf ("\n");
 154   no_problems = false;
 155 }
 156
 157 /* Print error message and exit.  */
 158
 159 static void
 160 fatal (s1, s2)
 161      char *s1, *s2;
 162 {
 163   error (s1, s2);
 164   exit (1);
 165 }
 166
 167 /* Like malloc but get fatal error if memory is exhausted.  */
 168
 169 static long *
 170 xmalloc (size)
 171      int size;
 172 {
 173   long *result = (long *) malloc (((unsigned) size));
 174   if (result == ((long *) NULL))
 175     fatal ("virtual memory exhausted", 0);
 176   return result;
 177 }
 178
 179 static long *
 180 xrealloc (ptr, size)
 181      long *ptr;
 182      int size;
 183 {
 184   long *result = (long *) realloc (ptr, ((unsigned) size));
 185   if (result == ((long *) NULL))
 186     fatal ("virtual memory exhausted");
 187   return result;
 188 }
 189 \f
 190 /* Initialize a linebuffer for use */
 191
 192 void
 193 init_linebuffer (linebuffer)
 194      struct linebuffer *linebuffer;
 195 {
 196   linebuffer->size = INITIAL_LINE_SIZE;
 197   linebuffer->buffer = ((char *) xmalloc (INITIAL_LINE_SIZE));
 198 }
 199
 200 /* Read a line of text from `stream' into `linebuffer'.
 201  * Return the length of the line.
 202  */
 203
 204 long
 205 readline (linebuffer, stream)
 206      struct linebuffer *linebuffer;
 207      FILE *stream;
 208 {
 209   char *buffer = linebuffer->buffer;
 210   char *p = linebuffer->buffer;
 211   char *end = p + linebuffer->size;
 212
 213   while (true)
 214     {
 215       int c = getc (stream);
 216       if (p == end)
 217         {
 218           linebuffer->size *= 2;
 219           buffer = ((char *) xrealloc (buffer, linebuffer->size));
 220           p = buffer + (p - linebuffer->buffer);
 221           end = buffer + linebuffer->size;
 222           linebuffer->buffer = buffer;
 223         }
 224       if (c < 0 || c == '\n')
 225         {
 226           *p = 0;
 227           break;
 228         }
 229       *p++ = c;
 230     }
 231
 232   return p - buffer;
 233 }
 234 \f
 235 /* Extract a colon-terminated keyword from the string FIELD.
 236    Return that keyword as a string stored in a static buffer.
 237    Store the address of the rest of the string into *REST.
 238
 239    If there is no keyword, return NULL and don't alter *REST.  */
 240
 241 char *
 242 get_keyword (field, rest)
 243      register char *field;
 244      char **rest;
 245 {
 246   static char keyword[KEYWORD_SIZE];
 247   register char *ptr;
 248   register char c;
 249
 250   ptr = &keyword[0];
 251   c = *field++;
 252   if (isspace (c) || c == ':')
 253     return ((char *) NULL);
 254   *ptr++ = (islower (c) ? toupper (c) : c);
 255   while (((c = *field++) != ':') && ! isspace (c))
 256     *ptr++ = (islower (c) ? toupper (c) : c);
 257   *ptr++ = '\0';
 258   while (isspace (c))
 259     c = *field++;
 260   if (c != ':')
 261     return ((char *) NULL);
 262   *rest = field;
 263   return &keyword[0];
 264 }
 265
 266 /* Nonzero if the string FIELD starts with a colon-terminated keyword.  */
 267
 268 boolean
 269 has_keyword (field)
 270      char *field;
 271 {
 272   char *ignored;
 273   return (get_keyword (field, &ignored) != ((char *) NULL));
 274 }
 275
 276 /* Store the string FIELD, followed by any lines in THE_LIST,
 277    into the buffer WHERE.
 278    Concatenate lines, putting just a space between them.
 279    Delete everything contained in parentheses.
 280    When a recipient name contains <...>, we discard
 281    everything except what is inside the <...>.
 282
 283    We don't pay attention to overflowing WHERE;
 284    the caller has to make it big enough.  */
 285
 286 char *
 287 add_field (the_list, field, where)
 288      line_list the_list;
 289      register char *field, *where;
 290 {
 291   register char c;
 292   while (true)
 293     {
 294       char *this_recipient_where;
 295       int in_quotes = 0;
 296
 297       *where++ = ' ';
 298       this_recipient_where = where;
 299
 300       while ((c = *field++) != '\0')
 301         {
 302           if (c == '\\')
 303             *where++ = c;
 304           else if (c == '"')
 305             {
 306               in_quotes = ! in_quotes;
 307               *where++ = c;
 308             }
 309           else if (in_quotes)
 310             *where++ = c;
 311           else if (c == '(')
 312             {
 313               while (*field && *field != ')') ++field;
 314               if (! (*field++)) break; /* no close */
 315               continue;
 316             }
 317           else if (c == ',')
 318             {
 319               *where++ = ' ';
 320               /* When we get to the end of one recipient,
 321                  don't discard it if the next one has <...>.  */
 322               this_recipient_where = where;
 323             }
 324           else if (c == '<')
 325             /* Discard everything we got before the `<'.  */
 326             where = this_recipient_where;
 327           else if (c == '>')
 328             /* Discard the rest of this name that follows the `>'.  */
 329             {
 330               while (*field && *field != ',') ++field;
 331               if (! (*field++)) break; /* no comma */
 332               continue;
 333             }
 334           else
 335             *where++ = c;
 336         }
 337       if (the_list == NIL) break;
 338       field = the_list->string;
 339       the_list = the_list->continuation;
 340     }
 341   return where;
 342 }
 343 \f
 344 line_list
 345 make_file_preface ()
 346 {
 347   char *the_string, *temp;
 348   long idiotic_interface;
 349   long prefix_length;
 350   long user_length;
 351   long date_length;
 352   line_list result;
 353
 354   prefix_length = strlen (FROM_PREFIX);
 355   time (&idiotic_interface);
 356   the_date = ctime (&idiotic_interface);
 357   /* the_date has an unwanted newline at the end */
 358   date_length = strlen (the_date) - 1;
 359   the_date[date_length] = '\0';
 360   temp = cuserid ((char *) NULL);
 361   user_length = strlen (temp);
 362   the_user = alloc_string (user_length + 1);
 363   strcpy (the_user, temp);
 364   the_string = alloc_string (3 + prefix_length +
 365                              user_length +
 366                              date_length);
 367   temp = the_string;
 368   strcpy (temp, FROM_PREFIX);
 369   temp = &temp[prefix_length];
 370   *temp++ = ' ';
 371   strcpy (temp, the_user);
 372   temp = &temp[user_length];
 373   *temp++ = ' ';
 374   strcpy (temp, the_date);
 375   result = new_list ();
 376   result->string = the_string;
 377   result->continuation = ((line_list) NULL);
 378   return result;
 379 }
 380
 381 void
 382 write_line_list (the_list, the_stream)
 383      register line_list the_list;
 384      FILE *the_stream;
 385 {
 386   for ( ;
 387       the_list != ((line_list) NULL) ;
 388       the_list = the_list->continuation)
 389     {
 390       fputs (the_list->string, the_stream);
 391       putc ('\n', the_stream);
 392     }
 393   return;
 394 }
 395 \f
 396 int
 397 close_the_streams ()
 398 {
 399   register stream_list rem;
 400   for (rem = the_streams;
 401        rem != ((stream_list) NULL);
 402        rem = rem->rest_streams)
 403     no_problems = (no_problems &&
 404                    ((*rem->action) (rem->handle) == 0));
 405   the_streams = ((stream_list) NULL);
 406   return (no_problems ? 0 : 1);
 407 }
 408
 409 void
 410 add_a_stream (the_stream, closing_action)
 411      FILE *the_stream;
 412      int (*closing_action)();
 413 {
 414   stream_list old = the_streams;
 415   the_streams = new_stream ();
 416   the_streams->handle = the_stream;
 417   the_streams->action = closing_action;
 418   the_streams->rest_streams = old;
 419   return;
 420 }
 421
 422 int
 423 my_fclose (the_file)
 424      FILE *the_file;
 425 {
 426   putc ('\n', the_file);
 427   fflush (the_file);
 428   return fclose (the_file);
 429 }
 430
 431 boolean
 432 open_a_file (name)
 433      char *name;
 434 {
 435   FILE *the_stream = fopen (name, "a");
 436   if (the_stream != ((FILE *) NULL))
 437     {
 438       add_a_stream (the_stream, my_fclose);
 439       if (the_user == ((char *) NULL))
 440         file_preface = make_file_preface ();
 441       write_line_list (file_preface, the_stream);
 442       return true;
 443     }
 444   return false;
 445 }
 446
 447 void
 448 put_string (s)
 449      char *s;
 450 {
 451   register stream_list rem;
 452   for (rem = the_streams;
 453        rem != ((stream_list) NULL);
 454        rem = rem->rest_streams)
 455     fputs (s, rem->handle);
 456   return;
 457 }
 458
 459 void
 460 put_line (string)
 461      char *string;
 462 {
 463   register stream_list rem;
 464   for (rem = the_streams;
 465        rem != ((stream_list) NULL);
 466        rem = rem->rest_streams)
 467     {
 468       char *s = string;
 469       int column = 0;
 470
 471       /* Divide STRING into lines.  */
 472       while (*s != 0)
 473         {
 474           char *breakpos;
 475
 476           /* Find the last char that fits.  */
 477           for (breakpos = s; *breakpos && column < 78; ++breakpos)
 478             {
 479               if (*breakpos == '\t')
 480                 column += 8;
 481               else
 482                 column++;
 483             }
 484           /* If we didn't reach end of line, break the line.  */
 485           if (*breakpos)
 486             {
 487               /* Back up to just after the last comma that fits.  */
 488               while (breakpos != s && breakpos[-1] != ',') --breakpos;
 489
 490               if (breakpos == s)
 491                 {
 492                   /* If no comma fits, move past the first address anyway.  */
 493                   while (*breakpos != 0 && *breakpos != ',') ++breakpos;
 494                   if (*breakpos != 0)
 495                     /* Include the comma after it.  */
 496                     ++breakpos;
 497                 }
 498             }
 499           /* Output that much, then break the line.  */
 500           fwrite (s, 1, breakpos - s, rem->handle);
 501           column = 8;
 502
 503           /* Skip whitespace and prepare to print more addresses.  */
 504           s = breakpos;
 505           while (*s == ' ' || *s == '\t') ++s;
 506           if (*s != 0)
 507             fputs ("\n\t", rem->handle);
 508         }
 509       putc ('\n', rem->handle);
 510     }
 511   return;
 512 }
 513 \f
 514 #define mail_error error
 515
 516 /* Handle an FCC field.  FIELD is the text of the first line (after
 517    the header name), and THE_LIST holds the continuation lines if any.
 518    Call open_a_file for each file.  */
 519
 520 void
 521 setup_files (the_list, field)
 522      register line_list the_list;
 523      register char *field;
 524 {
 525   register char *start;
 526   register char c;
 527   while (true)
 528     {
 529       while (((c = *field) != '\0')
 530              && (c == ' '
 531                  || c == '\t'
 532                  || c == ','))
 533         field += 1;
 534       if (c != '\0')
 535         {
 536           start = field;
 537           while (((c = *field) != '\0')
 538                  && c != ' '
 539                  && c != '\t'
 540                  && c != ',')
 541             field += 1;
 542           *field = '\0';
 543           if (!open_a_file (start))
 544             mail_error ("Could not open file %s", start);
 545           *field = c;
 546           if (c != '\0') continue;
 547         }
 548       if (the_list == ((line_list) NULL))
 549         return;
 550       field = the_list->string;
 551       the_list = the_list->continuation;
 552     }
 553 }
 554 \f
 555 /* Compute the total size of all recipient names stored in THE_HEADER.
 556    The result says how big to make the buffer to pass to parse_header.  */
 557
 558 int
 559 args_size (the_header)
 560      header the_header;
 561 {
 562   register header old = the_header;
 563   register line_list rem;
 564   register int size = 0;
 565   do
 566     {
 567       char *field;
 568       register char *keyword = get_keyword (the_header->text->string, &field);
 569       if ((strcmp (keyword, "TO") == 0)
 570           || (strcmp (keyword, "CC") == 0)
 571           || (strcmp (keyword, "BCC") == 0))
 572         {
 573           size += 1 + strlen (field);
 574           for (rem = the_header->text->continuation;
 575                rem != NIL;
 576                rem = rem->continuation)
 577             size += 1 + strlen (rem->string);
 578         }
 579       the_header = the_header->next;
 580     } while (the_header != old);
 581   return size;
 582 }
 583
 584 /* Scan the header described by the lists THE_HEADER,
 585    and put all recipient names into the buffer WHERE.
 586    Precede each recipient name with a space.
 587
 588    Also, if the header has any FCC fields, call setup_files for each one.  */
 589
 590 parse_header (the_header, where)
 591      header the_header;
 592      register char *where;
 593 {
 594   register header old = the_header;
 595   do
 596     {
 597       char *field;
 598       register char *keyword = get_keyword (the_header->text->string, &field);
 599       if (strcmp (keyword, "TO") == 0)
 600         where = add_field (the_header->text->continuation, field, where);
 601       else if (strcmp (keyword, "CC") == 0)
 602         where = add_field (the_header->text->continuation, field, where);
 603       else if (strcmp (keyword, "BCC") == 0)
 604         {
 605           where = add_field (the_header->text->continuation, field, where);
 606           the_header->previous->next = the_header->next;
 607           the_header->next->previous = the_header->previous;
 608         }
 609       else if (strcmp (keyword, "FCC") == 0)
 610         setup_files (the_header->text->continuation, field);
 611       the_header = the_header->next;
 612     } while (the_header != old);
 613   *where = '\0';
 614   return;
 615 }
 616 \f
 617 /* Read lines from the input until we get a blank line.
 618    Create a list of `header' objects, one for each header field,
 619    each of which points to a list of `line_list' objects,
 620    one for each line in that field.
 621    Continuation lines are grouped in the headers they continue.  */
 622
 623 header
 624 read_header ()
 625 {
 626   register header the_header = ((header) NULL);
 627   register line_list *next_line = ((line_list *) NULL);
 628
 629   init_linebuffer (&lb);
 630
 631   do
 632     {
 633       long length;
 634       register char *line;
 635
 636       readline (&lb, stdin);
 637       line = lb.buffer;
 638       length = strlen (line);
 639       if (length == 0) break;
 640
 641       if (has_keyword (line))
 642         {
 643           register header old = the_header;
 644           the_header = new_header ();
 645           if (old == ((header) NULL))
 646             {
 647               the_header->next = the_header;
 648               the_header->previous = the_header;
 649             }
 650           else
 651             {
 652               the_header->previous = old;
 653               the_header->next = old->next;
 654               old->next = the_header;
 655             }
 656           next_line = &(the_header->text);
 657         }
 658
 659       if (next_line == ((line_list *) NULL))
 660         {
 661           /* Not a valid header */
 662           exit (1);
 663         }
 664       *next_line = new_list ();
 665       (*next_line)->string = alloc_string (length);
 666       strcpy (((*next_line)->string), line);
 667       next_line = &((*next_line)->continuation);
 668       *next_line = NIL;
 669
 670     } while (true);
 671
 672   return the_header->next;
 673 }
 674 \f
 675 void
 676 write_header (the_header)
 677      header the_header;
 678 {
 679   register header old = the_header;
 680   do
 681     {
 682       register line_list the_list;
 683       for (the_list = the_header->text;
 684            the_list != NIL;
 685            the_list = the_list->continuation)
 686         put_line (the_list->string);
 687       the_header = the_header->next;
 688     } while (the_header != old);
 689   put_line ("");
 690   return;
 691 }
 692 \f
 693 void
 694 main (argc, argv)
 695      int argc;
 696      char **argv;
 697 {
 698   char *command_line;
 699   header the_header;
 700   long name_length;
 701   char *mail_program_name;
 702   char buf[BUFLEN + 1];
 703   register int size;
 704   FILE *the_pipe;
 705
 706   extern char *getenv ();
 707
 708   mail_program_name = getenv ("FAKEMAILER");
 709   if (!(mail_program_name && *mail_program_name))
 710     mail_program_name = MAIL_PROGRAM_NAME;
 711   name_length = strlen (mail_program_name);
 712
 713   my_name = MY_NAME;
 714   the_streams = ((stream_list) NULL);
 715   the_date = ((char *) NULL);
 716   the_user = ((char *) NULL);
 717
 718   the_header = read_header ();
 719   command_line = alloc_string (name_length + args_size (the_header));
 720   strcpy (command_line, mail_program_name);
 721   parse_header (the_header, &command_line[name_length]);
 722
 723   the_pipe = popen (command_line, "w");
 724   if (the_pipe == ((FILE *) NULL))
 725     fatal ("cannot open pipe to real mailer");
 726
 727   add_a_stream (the_pipe, pclose);
 728
 729   write_header (the_header);
 730
 731   /* Dump the message itself */
 732
 733   while (!feof (stdin))
 734     {
 735       size = fread (buf, 1, BUFLEN, stdin);
 736       buf[size] = '\0';
 737       put_string (buf);
 738     }
 739
 740   exit (close_the_streams ());
 741 }
 742
 743 #endif /* not MSDOS */
 744 #endif /* not BSD 4.2 (or newer) */