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