lib-src/fakemail.c

   1 /* sendmail-like interface to /bin/mail for system V,
   2    Copyright (C) 1985, 1994, 1999, 2001, 2002, 2003, 2004,
   3                  2005, 2006, 2007, 2008  Free Software Foundation, Inc.
   4
   5 This file is part of GNU Emacs.
   6
   7 GNU Emacs is free software; you can redistribute it and/or modify
   8 it under the terms of the GNU General Public License as published by
   9 the Free Software Foundation; either version 3, or (at your option)
  10 any later version.
  11
  12 GNU Emacs is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 GNU General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GNU Emacs; see the file COPYING.  If not, write to
  19 the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  20 Boston, MA 02110-1301, USA.  */
  21
  22 #define _XOPEN_SOURCE 500       /* for cuserid */
  23
  24 #ifdef HAVE_CONFIG_H
  25 #include <config.h>
  26 #endif
  27
  28 #if defined (BSD_SYSTEM) && !defined (BSD4_1) && !defined (USE_FAKEMAIL)
  29 /* This program isnot used in BSD, so just avoid loader complaints.  */
  30 int
  31 main ()
  32 {
  33   return 0;
  34 }
  35 #else /* not BSD 4.2 (or newer) */
  36 #ifdef MSDOS
  37 int
  38 main ()
  39 {
  40   return 0;
  41 }
  42 #else /* not MSDOS */
  43 /* This conditional contains all the rest of the file.  */
  44
  45 /* These are defined in config in some versions. */
  46
  47 #ifdef static
  48 #undef static
  49 #endif
  50
  51 #ifdef WINDOWSNT
  52 #include "ntlib.h"
  53 #endif
  54
  55 #include <stdio.h>
  56 #include <string.h>
  57 #include <ctype.h>
  58 #include <time.h>
  59 #include <pwd.h>
  60
  61 /* This is to declare cuserid.  */
  62 #ifdef HAVE_UNISTD_H
  63 #include <unistd.h>
  64 #endif
  65 \f
  66 /* Type definitions */
  67
  68 #define boolean int
  69 #define true 1
  70 #define false 0
  71
  72 #define TM_YEAR_BASE 1900
  73
  74 /* Nonzero if TM_YEAR is a struct tm's tm_year value that causes
  75    asctime to have well-defined behavior.  */
  76 #ifndef TM_YEAR_IN_ASCTIME_RANGE
  77 # define TM_YEAR_IN_ASCTIME_RANGE(tm_year) \
  78     (1000 - TM_YEAR_BASE <= (tm_year) && (tm_year) <= 9999 - TM_YEAR_BASE)
  79 #endif
  80
  81 /* Various lists */
  82
  83 struct line_record
  84 {
  85   char *string;
  86   struct line_record *continuation;
  87 };
  88 typedef struct line_record *line_list;
  89
  90 struct header_record
  91 {
  92   line_list text;
  93   struct header_record *next;
  94   struct header_record *previous;
  95 };
  96 typedef struct header_record *header;
  97
  98 struct stream_record
  99 {
 100   FILE *handle;
 101   int (*action)();
 102   struct stream_record *rest_streams;
 103 };
 104 typedef struct stream_record *stream_list;
 105
 106 /* A `struct linebuffer' is a structure which holds a line of text.
 107  * `readline' reads a line from a stream into a linebuffer
 108  * and works regardless of the length of the line.
 109  */
 110
 111 struct linebuffer
 112 {
 113   long size;
 114   char *buffer;
 115 };
 116
 117 struct linebuffer lb;
 118
 119 #define new_list()                                      \
 120   ((line_list) xmalloc (sizeof (struct line_record)))
 121 #define new_header()                            \
 122   ((header) xmalloc (sizeof (struct header_record)))
 123 #define new_stream()                            \
 124   ((stream_list) xmalloc (sizeof (struct stream_record)))
 125 #define alloc_string(nchars)                            \
 126   ((char *) xmalloc ((nchars) + 1))
 127 \f
 128 /* Global declarations */
 129
 130 #define BUFLEN 1024
 131 #define KEYWORD_SIZE 256
 132 #define FROM_PREFIX "From"
 133 #define MY_NAME "fakemail"
 134 #define NIL ((line_list) NULL)
 135 #define INITIAL_LINE_SIZE 200
 136
 137 #ifndef MAIL_PROGRAM_NAME
 138 #define MAIL_PROGRAM_NAME "/bin/mail"
 139 #endif
 140
 141 static char *my_name;
 142 static char *the_date;
 143 static char *the_user;
 144 static line_list file_preface;
 145 static stream_list the_streams;
 146 static boolean no_problems = true;
 147
 148 extern FILE *popen ();
 149 extern int fclose (), pclose ();
 150
 151 #ifdef CURRENT_USER
 152 extern struct passwd *getpwuid ();
 153 extern unsigned short geteuid ();
 154 static struct passwd *my_entry;
 155 #define cuserid(s)                              \
 156 (my_entry = getpwuid (((int) geteuid ())),      \
 157  my_entry->pw_name)
 158 #endif
 159 \f
 160 /* Utilities */
 161
 162 /* Print error message.  `s1' is printf control string, `s2' is arg for it. */
 163
 164 static void
 165 error (s1, s2)
 166      char *s1, *s2;
 167 {
 168   printf ("%s: ", my_name);
 169   printf (s1, s2);
 170   printf ("\n");
 171   no_problems = false;
 172 }
 173
 174 /* Print error message and exit.  */
 175
 176 static void
 177 fatal (s1)
 178      char *s1;
 179 {
 180   error ("%s", s1);
 181   exit (EXIT_FAILURE);
 182 }
 183
 184 /* Like malloc but get fatal error if memory is exhausted.  */
 185
 186 static long *
 187 xmalloc (size)
 188      int size;
 189 {
 190   long *result = (long *) malloc (((unsigned) size));
 191   if (result == ((long *) NULL))
 192     fatal ("virtual memory exhausted");
 193   return result;
 194 }
 195
 196 static long *
 197 xrealloc (ptr, size)
 198      long *ptr;
 199      int size;
 200 {
 201   long *result = (long *) realloc (ptr, ((unsigned) size));
 202   if (result == ((long *) NULL))
 203     fatal ("virtual memory exhausted");
 204   return result;
 205 }
 206 \f
 207 /* Initialize a linebuffer for use */
 208
 209 void
 210 init_linebuffer (linebuffer)
 211      struct linebuffer *linebuffer;
 212 {
 213   linebuffer->size = INITIAL_LINE_SIZE;
 214   linebuffer->buffer = ((char *) xmalloc (INITIAL_LINE_SIZE));
 215 }
 216
 217 /* Read a line of text from `stream' into `linebuffer'.
 218    Return the length of the line.  */
 219
 220 long
 221 readline (linebuffer, stream)
 222      struct linebuffer *linebuffer;
 223      FILE *stream;
 224 {
 225   char *buffer = linebuffer->buffer;
 226   char *p = linebuffer->buffer;
 227   char *end = p + linebuffer->size;
 228
 229   while (true)
 230     {
 231       int c = getc (stream);
 232       if (p == end)
 233         {
 234           linebuffer->size *= 2;
 235           buffer = ((char *) xrealloc ((long *)buffer, linebuffer->size));
 236           p = buffer + (p - linebuffer->buffer);
 237           end = buffer + linebuffer->size;
 238           linebuffer->buffer = buffer;
 239         }
 240       if (c < 0 || c == '\n')
 241         {
 242           *p = 0;
 243           break;
 244         }
 245       *p++ = c;
 246     }
 247
 248   return p - buffer;
 249 }
 250 \f
 251 /* Extract a colon-terminated keyword from the string FIELD.
 252    Return that keyword as a string stored in a static buffer.
 253    Store the address of the rest of the string into *REST.
 254
 255    If there is no keyword, return NULL and don't alter *REST.  */
 256
 257 char *
 258 get_keyword (field, rest)
 259      register char *field;
 260      char **rest;
 261 {
 262   static char keyword[KEYWORD_SIZE];
 263   register char *ptr;
 264   register int c;
 265
 266   ptr = &keyword[0];
 267   c = (unsigned char) *field++;
 268   if (isspace (c) || c == ':')
 269     return ((char *) NULL);
 270   *ptr++ = (islower (c) ? toupper (c) : c);
 271   while (((c = (unsigned char) *field++) != ':') && ! isspace (c))
 272     *ptr++ = (islower (c) ? toupper (c) : c);
 273   *ptr++ = '\0';
 274   while (isspace (c))
 275     c = (unsigned char) *field++;
 276   if (c != ':')
 277     return ((char *) NULL);
 278   *rest = field;
 279   return &keyword[0];
 280 }
 281
 282 /* Nonzero if the string FIELD starts with a colon-terminated keyword.  */
 283
 284 boolean
 285 has_keyword (field)
 286      char *field;
 287 {
 288   char *ignored;
 289   return (get_keyword (field, &ignored) != ((char *) NULL));
 290 }
 291
 292 /* Store the string FIELD, followed by any lines in THE_LIST,
 293    into the buffer WHERE.
 294    Concatenate lines, putting just a space between them.
 295    Delete everything contained in parentheses.
 296    When a recipient name contains <...>, we discard
 297    everything except what is inside the <...>.
 298
 299    We don't pay attention to overflowing WHERE;
 300    the caller has to make it big enough.  */
 301
 302 char *
 303 add_field (the_list, field, where)
 304      line_list the_list;
 305      register char *field, *where;
 306 {
 307   register char c;
 308   while (true)
 309     {
 310       char *this_recipient_where;
 311       int in_quotes = 0;
 312
 313       *where++ = ' ';
 314       this_recipient_where = where;
 315
 316       while ((c = *field++) != '\0')
 317         {
 318           if (c == '\\')
 319             *where++ = c;
 320           else if (c == '"')
 321             {
 322               in_quotes = ! in_quotes;
 323               *where++ = c;
 324             }
 325           else if (in_quotes)
 326             *where++ = c;
 327           else if (c == '(')
 328             {
 329               while (*field && *field != ')') ++field;
 330               if (! (*field++)) break; /* no close */
 331               continue;
 332             }
 333           else if (c == ',')
 334             {
 335               *where++ = ' ';
 336               /* When we get to the end of one recipient,
 337                  don't discard it if the next one has <...>.  */
 338               this_recipient_where = where;
 339             }
 340           else if (c == '<')
 341             /* Discard everything we got before the `<'.  */
 342             where = this_recipient_where;
 343           else if (c == '>')
 344             /* Discard the rest of this name that follows the `>'.  */
 345             {
 346               while (*field && *field != ',') ++field;
 347               if (! (*field++)) break; /* no comma */
 348               continue;
 349             }
 350           else
 351             *where++ = c;
 352         }
 353       if (the_list == NIL) break;
 354       field = the_list->string;
 355       the_list = the_list->continuation;
 356     }
 357   return where;
 358 }
 359 \f
 360 line_list
 361 make_file_preface ()
 362 {
 363   char *the_string, *temp;
 364   long idiotic_interface;
 365   struct tm *tm;
 366   long prefix_length;
 367   long user_length;
 368   long date_length;
 369   line_list result;
 370
 371   prefix_length = strlen (FROM_PREFIX);
 372   time (&idiotic_interface);
 373   /* Convert to a string, checking for out-of-range time stamps.
 374      Don't use 'ctime', as that might dump core if the hardware clock
 375      is set to a bizarre value.  */
 376   tm = localtime (&idiotic_interface);
 377   if (! (tm && TM_YEAR_IN_ASCTIME_RANGE (tm->tm_year)
 378          && (the_date = asctime (tm))))
 379     fatal ("current time is out of range");
 380   /* the_date has an unwanted newline at the end */
 381   date_length = strlen (the_date) - 1;
 382   the_date[date_length] = '\0';
 383   temp = cuserid ((char *) NULL);
 384   user_length = strlen (temp);
 385   the_user = alloc_string (user_length + 1);
 386   strcpy (the_user, temp);
 387   the_string = alloc_string (3 + prefix_length
 388                              + user_length
 389                              + date_length);
 390   temp = the_string;
 391   strcpy (temp, FROM_PREFIX);
 392   temp = &temp[prefix_length];
 393   *temp++ = ' ';
 394   strcpy (temp, the_user);
 395   temp = &temp[user_length];
 396   *temp++ = ' ';
 397   strcpy (temp, the_date);
 398   result = new_list ();
 399   result->string = the_string;
 400   result->continuation = ((line_list) NULL);
 401   return result;
 402 }
 403
 404 void
 405 write_line_list (the_list, the_stream)
 406      register line_list the_list;
 407      FILE *the_stream;
 408 {
 409   for ( ;
 410       the_list != ((line_list) NULL) ;
 411       the_list = the_list->continuation)
 412     {
 413       fputs (the_list->string, the_stream);
 414       putc ('\n', the_stream);
 415     }
 416   return;
 417 }
 418 \f
 419 int
 420 close_the_streams ()
 421 {
 422   register stream_list rem;
 423   for (rem = the_streams;
 424        rem != ((stream_list) NULL);
 425        rem = rem->rest_streams)
 426     no_problems = (no_problems &&
 427                    ((*rem->action) (rem->handle) == 0));
 428   the_streams = ((stream_list) NULL);
 429   return (no_problems ? EXIT_SUCCESS : EXIT_FAILURE);
 430 }
 431
 432 void
 433 add_a_stream (the_stream, closing_action)
 434      FILE *the_stream;
 435      int (*closing_action)();
 436 {
 437   stream_list old = the_streams;
 438   the_streams = new_stream ();
 439   the_streams->handle = the_stream;
 440   the_streams->action = closing_action;
 441   the_streams->rest_streams = old;
 442   return;
 443 }
 444
 445 int
 446 my_fclose (the_file)
 447      FILE *the_file;
 448 {
 449   putc ('\n', the_file);
 450   fflush (the_file);
 451   return fclose (the_file);
 452 }
 453
 454 boolean
 455 open_a_file (name)
 456      char *name;
 457 {
 458   FILE *the_stream = fopen (name, "a");
 459   if (the_stream != ((FILE *) NULL))
 460     {
 461       add_a_stream (the_stream, my_fclose);
 462       if (the_user == ((char *) NULL))
 463         file_preface = make_file_preface ();
 464       write_line_list (file_preface, the_stream);
 465       return true;
 466     }
 467   return false;
 468 }
 469
 470 void
 471 put_string (s)
 472      char *s;
 473 {
 474   register stream_list rem;
 475   for (rem = the_streams;
 476        rem != ((stream_list) NULL);
 477        rem = rem->rest_streams)
 478     fputs (s, rem->handle);
 479   return;
 480 }
 481
 482 void
 483 put_line (string)
 484      char *string;
 485 {
 486   register stream_list rem;
 487   for (rem = the_streams;
 488        rem != ((stream_list) NULL);
 489        rem = rem->rest_streams)
 490     {
 491       char *s = string;
 492       int column = 0;
 493
 494       /* Divide STRING into lines.  */
 495       while (*s != 0)
 496         {
 497           char *breakpos;
 498
 499           /* Find the last char that fits.  */
 500           for (breakpos = s; *breakpos && column < 78; ++breakpos)
 501             {
 502               if (*breakpos == '\t')
 503                 column += 8;
 504               else
 505                 column++;
 506             }
 507           /* If we didn't reach end of line, break the line.  */
 508           if (*breakpos)
 509             {
 510               /* Back up to just after the last comma that fits.  */
 511               while (breakpos != s && breakpos[-1] != ',') --breakpos;
 512
 513               if (breakpos == s)
 514                 {
 515                   /* If no comma fits, move past the first address anyway.  */
 516                   while (*breakpos != 0 && *breakpos != ',') ++breakpos;
 517                   if (*breakpos != 0)
 518                     /* Include the comma after it.  */
 519                     ++breakpos;
 520                 }
 521             }
 522           /* Output that much, then break the line.  */
 523           fwrite (s, 1, breakpos - s, rem->handle);
 524           column = 8;
 525
 526           /* Skip whitespace and prepare to print more addresses.  */
 527           s = breakpos;
 528           while (*s == ' ' || *s == '\t') ++s;
 529           if (*s != 0)
 530             fputs ("\n\t", rem->handle);
 531         }
 532       putc ('\n', rem->handle);
 533     }
 534   return;
 535 }
 536 \f
 537 #define mail_error error
 538
 539 /* Handle an FCC field.  FIELD is the text of the first line (after
 540    the header name), and THE_LIST holds the continuation lines if any.
 541    Call open_a_file for each file.  */
 542
 543 void
 544 setup_files (the_list, field)
 545      register line_list the_list;
 546      register char *field;
 547 {
 548   register char *start;
 549   register char c;
 550   while (true)
 551     {
 552       while (((c = *field) != '\0')
 553              && (c == ' '
 554                  || c == '\t'
 555                  || c == ','))
 556         field += 1;
 557       if (c != '\0')
 558         {
 559           start = field;
 560           while (((c = *field) != '\0')
 561                  && c != ' '
 562                  && c != '\t'
 563                  && c != ',')
 564             field += 1;
 565           *field = '\0';
 566           if (!open_a_file (start))
 567             mail_error ("Could not open file %s", start);
 568           *field = c;
 569           if (c != '\0') continue;
 570         }
 571       if (the_list == ((line_list) NULL))
 572         return;
 573       field = the_list->string;
 574       the_list = the_list->continuation;
 575     }
 576 }
 577 \f
 578 /* Compute the total size of all recipient names stored in THE_HEADER.
 579    The result says how big to make the buffer to pass to parse_header.  */
 580
 581 int
 582 args_size (the_header)
 583      header the_header;
 584 {
 585   register header old = the_header;
 586   register line_list rem;
 587   register int size = 0;
 588   do
 589     {
 590       char *field;
 591       register char *keyword = get_keyword (the_header->text->string, &field);
 592       if ((strcmp (keyword, "TO") == 0)
 593           || (strcmp (keyword, "CC") == 0)
 594           || (strcmp (keyword, "BCC") == 0))
 595         {
 596           size += 1 + strlen (field);
 597           for (rem = the_header->text->continuation;
 598                rem != NIL;
 599                rem = rem->continuation)
 600             size += 1 + strlen (rem->string);
 601         }
 602       the_header = the_header->next;
 603     } while (the_header != old);
 604   return size;
 605 }
 606
 607 /* Scan the header described by the lists THE_HEADER,
 608    and put all recipient names into the buffer WHERE.
 609    Precede each recipient name with a space.
 610
 611    Also, if the header has any FCC fields, call setup_files for each one.  */
 612
 613 void
 614 parse_header (the_header, where)
 615      header the_header;
 616      register char *where;
 617 {
 618   register header old = the_header;
 619   do
 620     {
 621       char *field;
 622       register char *keyword = get_keyword (the_header->text->string, &field);
 623       if (strcmp (keyword, "TO") == 0)
 624         where = add_field (the_header->text->continuation, field, where);
 625       else if (strcmp (keyword, "CC") == 0)
 626         where = add_field (the_header->text->continuation, field, where);
 627       else if (strcmp (keyword, "BCC") == 0)
 628         {
 629           where = add_field (the_header->text->continuation, field, where);
 630           the_header->previous->next = the_header->next;
 631           the_header->next->previous = the_header->previous;
 632         }
 633       else if (strcmp (keyword, "FCC") == 0)
 634         setup_files (the_header->text->continuation, field);
 635       the_header = the_header->next;
 636     } while (the_header != old);
 637   *where = '\0';
 638   return;
 639 }
 640 \f
 641 /* Read lines from the input until we get a blank line.
 642    Create a list of `header' objects, one for each header field,
 643    each of which points to a list of `line_list' objects,
 644    one for each line in that field.
 645    Continuation lines are grouped in the headers they continue.  */
 646
 647 header
 648 read_header ()
 649 {
 650   register header the_header = ((header) NULL);
 651   register line_list *next_line = ((line_list *) NULL);
 652
 653   init_linebuffer (&lb);
 654
 655   do
 656     {
 657       long length;
 658       register char *line;
 659
 660       readline (&lb, stdin);
 661       line = lb.buffer;
 662       length = strlen (line);
 663       if (length == 0) break;
 664
 665       if (has_keyword (line))
 666         {
 667           register header old = the_header;
 668           the_header = new_header ();
 669           if (old == ((header) NULL))
 670             {
 671               the_header->next = the_header;
 672               the_header->previous = the_header;
 673             }
 674           else
 675             {
 676               the_header->previous = old;
 677               the_header->next = old->next;
 678               old->next = the_header;
 679             }
 680           next_line = &(the_header->text);
 681         }
 682
 683       if (next_line == ((line_list *) NULL))
 684         {
 685           /* Not a valid header */
 686           exit (EXIT_FAILURE);
 687         }
 688       *next_line = new_list ();
 689       (*next_line)->string = alloc_string (length);
 690       strcpy (((*next_line)->string), line);
 691       next_line = &((*next_line)->continuation);
 692       *next_line = NIL;
 693
 694     } while (true);
 695
 696   if (! the_header)
 697     fatal ("input message has no header");
 698   return the_header->next;
 699 }
 700 \f
 701 void
 702 write_header (the_header)
 703      header the_header;
 704 {
 705   register header old = the_header;
 706   do
 707     {
 708       register line_list the_list;
 709       for (the_list = the_header->text;
 710            the_list != NIL;
 711            the_list = the_list->continuation)
 712         put_line (the_list->string);
 713       the_header = the_header->next;
 714     } while (the_header != old);
 715   put_line ("");
 716   return;
 717 }
 718 \f
 719 int
 720 main (argc, argv)
 721      int argc;
 722      char **argv;
 723 {
 724   char *command_line;
 725   header the_header;
 726   long name_length;
 727   char *mail_program_name;
 728   char buf[BUFLEN + 1];
 729   register int size;
 730   FILE *the_pipe;
 731
 732   extern char *getenv ();
 733
 734   mail_program_name = getenv ("FAKEMAILER");
 735   if (!(mail_program_name && *mail_program_name))
 736     mail_program_name = MAIL_PROGRAM_NAME;
 737   name_length = strlen (mail_program_name);
 738
 739   my_name = MY_NAME;
 740   the_streams = ((stream_list) NULL);
 741   the_date = ((char *) NULL);
 742   the_user = ((char *) NULL);
 743
 744   the_header = read_header ();
 745   command_line = alloc_string (name_length + args_size (the_header));
 746   strcpy (command_line, mail_program_name);
 747   parse_header (the_header, &command_line[name_length]);
 748
 749   the_pipe = popen (command_line, "w");
 750   if (the_pipe == ((FILE *) NULL))
 751     fatal ("cannot open pipe to real mailer");
 752
 753   add_a_stream (the_pipe, pclose);
 754
 755   write_header (the_header);
 756
 757   /* Dump the message itself */
 758
 759   while (!feof (stdin))
 760     {
 761       size = fread (buf, 1, BUFLEN, stdin);
 762       buf[size] = '\0';
 763       put_string (buf);
 764     }
 765
 766   exit (close_the_streams ());
 767 }
 768
 769 #endif /* not MSDOS */
 770 #endif /* not BSD 4.2 (or newer) */
 771
 772 /* arch-tag: acb0afa6-315a-4c5b-b9e3-def5725c8783
 773    (do not change this comment) */
 774
 775 /* fakemail.c ends here */