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, Inc., 59 Temple Place - Suite 330,
  19 Boston, MA 02111-1307, USA.  */
  20
  21
  22 /* This is needed to get the declaration of cuserid in GNU libc.  */
  23 #define _XOPEN_SOURCE 1
  24
  25 #define NO_SHORTNAMES
  26 #include <../src/config.h>
  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 read
  52 #undef read
  53 #undef write
  54 #undef open
  55 #undef close
  56 #endif
  57
  58 #ifdef WINDOWSNT
  59 #include "ntlib.h"
  60 #endif
  61
  62 #include <stdio.h>
  63 #include <string.h>
  64 #include <ctype.h>
  65 #include <time.h>
  66 #include <pwd.h>
  67
  68 /* This is to declare cuserid.  */
  69 #ifdef HAVE_UNISTD_H
  70 #include <unistd.h>
  71 #endif
  72
  73 #ifdef STDC_HEADERS
  74 #include <stdlib.h>
  75 #endif
  76 \f
  77 /* Type definitions */
  78
  79 #define boolean int
  80 #define true 1
  81 #define false 0
  82
  83 /* Various lists */
  84
  85 struct line_record
  86 {
  87   char *string;
  88   struct line_record *continuation;
  89 };
  90 typedef struct line_record *line_list;
  91
  92 struct header_record
  93 {
  94   line_list text;
  95   struct header_record *next;
  96   struct header_record *previous;
  97 };
  98 typedef struct header_record *header;
  99
 100 struct stream_record
 101 {
 102   FILE *handle;
 103   int (*action)();
 104   struct stream_record *rest_streams;
 105 };
 106 typedef struct stream_record *stream_list;
 107
 108 /* A `struct linebuffer' is a structure which holds a line of text.
 109  * `readline' reads a line from a stream into a linebuffer
 110  * and works regardless of the length of the line.
 111  */
 112
 113 struct linebuffer
 114 {
 115   long size;
 116   char *buffer;
 117 };
 118
 119 struct linebuffer lb;
 120
 121 #define new_list()                                      \
 122   ((line_list) xmalloc (sizeof (struct line_record)))
 123 #define new_header()                            \
 124   ((header) xmalloc (sizeof (struct header_record)))
 125 #define new_stream()                            \
 126   ((stream_list) xmalloc (sizeof (struct stream_record)))
 127 #define alloc_string(nchars)                            \
 128   ((char *) xmalloc ((nchars) + 1))
 129 \f
 130 /* Global declarations */
 131
 132 #define BUFLEN 1024
 133 #define KEYWORD_SIZE 256
 134 #define FROM_PREFIX "From"
 135 #define MY_NAME "fakemail"
 136 #define NIL ((line_list) NULL)
 137 #define INITIAL_LINE_SIZE 200
 138
 139 #ifndef MAIL_PROGRAM_NAME
 140 #define MAIL_PROGRAM_NAME "/bin/mail"
 141 #endif
 142
 143 static char *my_name;
 144 static char *the_date;
 145 static char *the_user;
 146 static line_list file_preface;
 147 static stream_list the_streams;
 148 static boolean no_problems = true;
 149
 150 extern FILE *popen ();
 151 extern int fclose (), pclose ();
 152
 153 #ifdef CURRENT_USER
 154 extern struct passwd *getpwuid ();
 155 extern unsigned short geteuid ();
 156 static struct passwd *my_entry;
 157 #define cuserid(s)                              \
 158 (my_entry = getpwuid (((int) geteuid ())),      \
 159  my_entry->pw_name)
 160 #endif
 161 \f
 162 /* Utilities */
 163
 164 /* Print error message.  `s1' is printf control string, `s2' is arg for it. */
 165
 166 static void
 167 error (s1, s2)
 168      char *s1, *s2;
 169 {
 170   printf ("%s: ", my_name);
 171   printf (s1, s2);
 172   printf ("\n");
 173   no_problems = false;
 174 }
 175
 176 /* Print error message and exit.  */
 177
 178 static void
 179 fatal (s1, s2)
 180      char *s1, *s2;
 181 {
 182   error (s1, s2);
 183   exit (1);
 184 }
 185
 186 /* Like malloc but get fatal error if memory is exhausted.  */
 187
 188 static long *
 189 xmalloc (size)
 190      int size;
 191 {
 192   long *result = (long *) malloc (((unsigned) size));
 193   if (result == ((long *) NULL))
 194     fatal ("virtual memory exhausted", 0);
 195   return result;
 196 }
 197
 198 static long *
 199 xrealloc (ptr, size)
 200      long *ptr;
 201      int size;
 202 {
 203   long *result = (long *) realloc (ptr, ((unsigned) size));
 204   if (result == ((long *) NULL))
 205     fatal ("virtual memory exhausted");
 206   return result;
 207 }
 208 \f
 209 /* Initialize a linebuffer for use */
 210
 211 void
 212 init_linebuffer (linebuffer)
 213      struct linebuffer *linebuffer;
 214 {
 215   linebuffer->size = INITIAL_LINE_SIZE;
 216   linebuffer->buffer = ((char *) xmalloc (INITIAL_LINE_SIZE));
 217 }
 218
 219 /* Read a line of text from `stream' into `linebuffer'.
 220  * Return the length of the line.
 221  */
 222
 223 long
 224 readline (linebuffer, stream)
 225      struct linebuffer *linebuffer;
 226      FILE *stream;
 227 {
 228   char *buffer = linebuffer->buffer;
 229   char *p = linebuffer->buffer;
 230   char *end = p + linebuffer->size;
 231
 232   while (true)
 233     {
 234       int c = getc (stream);
 235       if (p == end)
 236         {
 237           linebuffer->size *= 2;
 238           buffer = ((char *) xrealloc (buffer, linebuffer->size));
 239           p = buffer + (p - linebuffer->buffer);
 240           end = buffer + linebuffer->size;
 241           linebuffer->buffer = buffer;
 242         }
 243       if (c < 0 || c == '\n')
 244         {
 245           *p = 0;
 246           break;
 247         }
 248       *p++ = c;
 249     }
 250
 251   return p - buffer;
 252 }
 253 \f
 254 /* Extract a colon-terminated keyword from the string FIELD.
 255    Return that keyword as a string stored in a static buffer.
 256    Store the address of the rest of the string into *REST.
 257
 258    If there is no keyword, return NULL and don't alter *REST.  */
 259
 260 char *
 261 get_keyword (field, rest)
 262      register char *field;
 263      char **rest;
 264 {
 265   static char keyword[KEYWORD_SIZE];
 266   register char *ptr;
 267   register char c;
 268
 269   ptr = &keyword[0];
 270   c = *field++;
 271   if (isspace (c) || c == ':')
 272     return ((char *) NULL);
 273   *ptr++ = (islower (c) ? toupper (c) : c);
 274   while (((c = *field++) != ':') && ! isspace (c))
 275     *ptr++ = (islower (c) ? toupper (c) : c);
 276   *ptr++ = '\0';
 277   while (isspace (c))
 278     c = *field++;
 279   if (c != ':')
 280     return ((char *) NULL);
 281   *rest = field;
 282   return &keyword[0];
 283 }
 284
 285 /* Nonzero if the string FIELD starts with a colon-terminated keyword.  */
 286
 287 boolean
 288 has_keyword (field)
 289      char *field;
 290 {
 291   char *ignored;
 292   return (get_keyword (field, &ignored) != ((char *) NULL));
 293 }
 294
 295 /* Store the string FIELD, followed by any lines in THE_LIST,
 296    into the buffer WHERE.
 297    Concatenate lines, putting just a space between them.
 298    Delete everything contained in parentheses.
 299    When a recipient name contains <...>, we discard
 300    everything except what is inside the <...>.
 301
 302    We don't pay attention to overflowing WHERE;
 303    the caller has to make it big enough.  */
 304
 305 char *
 306 add_field (the_list, field, where)
 307      line_list the_list;
 308      register char *field, *where;
 309 {
 310   register char c;
 311   while (true)
 312     {
 313       char *this_recipient_where;
 314       int in_quotes = 0;
 315
 316       *where++ = ' ';
 317       this_recipient_where = where;
 318
 319       while ((c = *field++) != '\0')
 320         {
 321           if (c == '\\')
 322             *where++ = c;
 323           else if (c == '"')
 324             {
 325               in_quotes = ! in_quotes;
 326               *where++ = c;
 327             }
 328           else if (in_quotes)
 329             *where++ = c;
 330           else if (c == '(')
 331             {
 332               while (*field && *field != ')') ++field;
 333               if (! (*field++)) break; /* no close */
 334               continue;
 335             }
 336           else if (c == ',')
 337             {
 338               *where++ = ' ';
 339               /* When we get to the end of one recipient,
 340                  don't discard it if the next one has <...>.  */
 341               this_recipient_where = where;
 342             }
 343           else if (c == '<')
 344             /* Discard everything we got before the `<'.  */
 345             where = this_recipient_where;
 346           else if (c == '>')
 347             /* Discard the rest of this name that follows the `>'.  */
 348             {
 349               while (*field && *field != ',') ++field;
 350               if (! (*field++)) break; /* no comma */
 351               continue;
 352             }
 353           else
 354             *where++ = c;
 355         }
 356       if (the_list == NIL) break;
 357       field = the_list->string;
 358       the_list = the_list->continuation;
 359     }
 360   return where;
 361 }
 362 \f
 363 line_list
 364 make_file_preface ()
 365 {
 366   char *the_string, *temp;
 367   long idiotic_interface;
 368   long prefix_length;
 369   long user_length;
 370   long date_length;
 371   line_list result;
 372
 373   prefix_length = strlen (FROM_PREFIX);
 374   time (&idiotic_interface);
 375   the_date = ctime (&idiotic_interface);
 376   /* the_date has an unwanted newline at the end */
 377   date_length = strlen (the_date) - 1;
 378   the_date[date_length] = '\0';
 379   temp = cuserid ((char *) NULL);
 380   user_length = strlen (temp);
 381   the_user = alloc_string (user_length + 1);
 382   strcpy (the_user, temp);
 383   the_string = alloc_string (3 + prefix_length
 384                              + user_length
 385                              + date_length);
 386   temp = the_string;
 387   strcpy (temp, FROM_PREFIX);
 388   temp = &temp[prefix_length];
 389   *temp++ = ' ';
 390   strcpy (temp, the_user);
 391   temp = &temp[user_length];
 392   *temp++ = ' ';
 393   strcpy (temp, the_date);
 394   result = new_list ();
 395   result->string = the_string;
 396   result->continuation = ((line_list) NULL);
 397   return result;
 398 }
 399
 400 void
 401 write_line_list (the_list, the_stream)
 402      register line_list the_list;
 403      FILE *the_stream;
 404 {
 405   for ( ;
 406       the_list != ((line_list) NULL) ;
 407       the_list = the_list->continuation)
 408     {
 409       fputs (the_list->string, the_stream);
 410       putc ('\n', the_stream);
 411     }
 412   return;
 413 }
 414 \f
 415 int
 416 close_the_streams ()
 417 {
 418   register stream_list rem;
 419   for (rem = the_streams;
 420        rem != ((stream_list) NULL);
 421        rem = rem->rest_streams)
 422     no_problems = (no_problems &&
 423                    ((*rem->action) (rem->handle) == 0));
 424   the_streams = ((stream_list) NULL);
 425   return (no_problems ? 0 : 1);
 426 }
 427
 428 void
 429 add_a_stream (the_stream, closing_action)
 430      FILE *the_stream;
 431      int (*closing_action)();
 432 {
 433   stream_list old = the_streams;
 434   the_streams = new_stream ();
 435   the_streams->handle = the_stream;
 436   the_streams->action = closing_action;
 437   the_streams->rest_streams = old;
 438   return;
 439 }
 440
 441 int
 442 my_fclose (the_file)
 443      FILE *the_file;
 444 {
 445   putc ('\n', the_file);
 446   fflush (the_file);
 447   return fclose (the_file);
 448 }
 449
 450 boolean
 451 open_a_file (name)
 452      char *name;
 453 {
 454   FILE *the_stream = fopen (name, "a");
 455   if (the_stream != ((FILE *) NULL))
 456     {
 457       add_a_stream (the_stream, my_fclose);
 458       if (the_user == ((char *) NULL))
 459         file_preface = make_file_preface ();
 460       write_line_list (file_preface, the_stream);
 461       return true;
 462     }
 463   return false;
 464 }
 465
 466 void
 467 put_string (s)
 468      char *s;
 469 {
 470   register stream_list rem;
 471   for (rem = the_streams;
 472        rem != ((stream_list) NULL);
 473        rem = rem->rest_streams)
 474     fputs (s, rem->handle);
 475   return;
 476 }
 477
 478 void
 479 put_line (string)
 480      char *string;
 481 {
 482   register stream_list rem;
 483   for (rem = the_streams;
 484        rem != ((stream_list) NULL);
 485        rem = rem->rest_streams)
 486     {
 487       char *s = string;
 488       int column = 0;
 489
 490       /* Divide STRING into lines.  */
 491       while (*s != 0)
 492         {
 493           char *breakpos;
 494
 495           /* Find the last char that fits.  */
 496           for (breakpos = s; *breakpos && column < 78; ++breakpos)
 497             {
 498               if (*breakpos == '\t')
 499                 column += 8;
 500               else
 501                 column++;
 502             }
 503           /* If we didn't reach end of line, break the line.  */
 504           if (*breakpos)
 505             {
 506               /* Back up to just after the last comma that fits.  */
 507               while (breakpos != s && breakpos[-1] != ',') --breakpos;
 508
 509               if (breakpos == s)
 510                 {
 511                   /* If no comma fits, move past the first address anyway.  */
 512                   while (*breakpos != 0 && *breakpos != ',') ++breakpos;
 513                   if (*breakpos != 0)
 514                     /* Include the comma after it.  */
 515                     ++breakpos;
 516                 }
 517             }
 518           /* Output that much, then break the line.  */
 519           fwrite (s, 1, breakpos - s, rem->handle);
 520           column = 8;
 521
 522           /* Skip whitespace and prepare to print more addresses.  */
 523           s = breakpos;
 524           while (*s == ' ' || *s == '\t') ++s;
 525           if (*s != 0)
 526             fputs ("\n\t", rem->handle);
 527         }
 528       putc ('\n', rem->handle);
 529     }
 530   return;
 531 }
 532 \f
 533 #define mail_error error
 534
 535 /* Handle an FCC field.  FIELD is the text of the first line (after
 536    the header name), and THE_LIST holds the continuation lines if any.
 537    Call open_a_file for each file.  */
 538
 539 void
 540 setup_files (the_list, field)
 541      register line_list the_list;
 542      register char *field;
 543 {
 544   register char *start;
 545   register char c;
 546   while (true)
 547     {
 548       while (((c = *field) != '\0')
 549              && (c == ' '
 550                  || c == '\t'
 551                  || c == ','))
 552         field += 1;
 553       if (c != '\0')
 554         {
 555           start = field;
 556           while (((c = *field) != '\0')
 557                  && c != ' '
 558                  && c != '\t'
 559                  && c != ',')
 560             field += 1;
 561           *field = '\0';
 562           if (!open_a_file (start))
 563             mail_error ("Could not open file %s", start);
 564           *field = c;
 565           if (c != '\0') continue;
 566         }
 567       if (the_list == ((line_list) NULL))
 568         return;
 569       field = the_list->string;
 570       the_list = the_list->continuation;
 571     }
 572 }
 573 \f
 574 /* Compute the total size of all recipient names stored in THE_HEADER.
 575    The result says how big to make the buffer to pass to parse_header.  */
 576
 577 int
 578 args_size (the_header)
 579      header the_header;
 580 {
 581   register header old = the_header;
 582   register line_list rem;
 583   register int size = 0;
 584   do
 585     {
 586       char *field;
 587       register char *keyword = get_keyword (the_header->text->string, &field);
 588       if ((strcmp (keyword, "TO") == 0)
 589           || (strcmp (keyword, "CC") == 0)
 590           || (strcmp (keyword, "BCC") == 0))
 591         {
 592           size += 1 + strlen (field);
 593           for (rem = the_header->text->continuation;
 594                rem != NIL;
 595                rem = rem->continuation)
 596             size += 1 + strlen (rem->string);
 597         }
 598       the_header = the_header->next;
 599     } while (the_header != old);
 600   return size;
 601 }
 602
 603 /* Scan the header described by the lists THE_HEADER,
 604    and put all recipient names into the buffer WHERE.
 605    Precede each recipient name with a space.
 606
 607    Also, if the header has any FCC fields, call setup_files for each one.  */
 608
 609 void
 610 parse_header (the_header, where)
 611      header the_header;
 612      register char *where;
 613 {
 614   register header old = the_header;
 615   do
 616     {
 617       char *field;
 618       register char *keyword = get_keyword (the_header->text->string, &field);
 619       if (strcmp (keyword, "TO") == 0)
 620         where = add_field (the_header->text->continuation, field, where);
 621       else if (strcmp (keyword, "CC") == 0)
 622         where = add_field (the_header->text->continuation, field, where);
 623       else if (strcmp (keyword, "BCC") == 0)
 624         {
 625           where = add_field (the_header->text->continuation, field, where);
 626           the_header->previous->next = the_header->next;
 627           the_header->next->previous = the_header->previous;
 628         }
 629       else if (strcmp (keyword, "FCC") == 0)
 630         setup_files (the_header->text->continuation, field);
 631       the_header = the_header->next;
 632     } while (the_header != old);
 633   *where = '\0';
 634   return;
 635 }
 636 \f
 637 /* Read lines from the input until we get a blank line.
 638    Create a list of `header' objects, one for each header field,
 639    each of which points to a list of `line_list' objects,
 640    one for each line in that field.
 641    Continuation lines are grouped in the headers they continue.  */
 642
 643 header
 644 read_header ()
 645 {
 646   register header the_header = ((header) NULL);
 647   register line_list *next_line = ((line_list *) NULL);
 648
 649   init_linebuffer (&lb);
 650
 651   do
 652     {
 653       long length;
 654       register char *line;
 655
 656       readline (&lb, stdin);
 657       line = lb.buffer;
 658       length = strlen (line);
 659       if (length == 0) break;
 660
 661       if (has_keyword (line))
 662         {
 663           register header old = the_header;
 664           the_header = new_header ();
 665           if (old == ((header) NULL))
 666             {
 667               the_header->next = the_header;
 668               the_header->previous = the_header;
 669             }
 670           else
 671             {
 672               the_header->previous = old;
 673               the_header->next = old->next;
 674               old->next = the_header;
 675             }
 676           next_line = &(the_header->text);
 677         }
 678
 679       if (next_line == ((line_list *) NULL))
 680         {
 681           /* Not a valid header */
 682           exit (1);
 683         }
 684       *next_line = new_list ();
 685       (*next_line)->string = alloc_string (length);
 686       strcpy (((*next_line)->string), line);
 687       next_line = &((*next_line)->continuation);
 688       *next_line = NIL;
 689
 690     } while (true);
 691
 692   return the_header->next;
 693 }
 694 \f
 695 void
 696 write_header (the_header)
 697      header the_header;
 698 {
 699   register header old = the_header;
 700   do
 701     {
 702       register line_list the_list;
 703       for (the_list = the_header->text;
 704            the_list != NIL;
 705            the_list = the_list->continuation)
 706         put_line (the_list->string);
 707       the_header = the_header->next;
 708     } while (the_header != old);
 709   put_line ("");
 710   return;
 711 }
 712 \f
 713 int
 714 main (argc, argv)
 715      int argc;
 716      char **argv;
 717 {
 718   char *command_line;
 719   header the_header;
 720   long name_length;
 721   char *mail_program_name;
 722   char buf[BUFLEN + 1];
 723   register int size;
 724   FILE *the_pipe;
 725
 726   extern char *getenv ();
 727
 728   mail_program_name = getenv ("FAKEMAILER");
 729   if (!(mail_program_name && *mail_program_name))
 730     mail_program_name = MAIL_PROGRAM_NAME;
 731   name_length = strlen (mail_program_name);
 732
 733   my_name = MY_NAME;
 734   the_streams = ((stream_list) NULL);
 735   the_date = ((char *) NULL);
 736   the_user = ((char *) NULL);
 737
 738   the_header = read_header ();
 739   command_line = alloc_string (name_length + args_size (the_header));
 740   strcpy (command_line, mail_program_name);
 741   parse_header (the_header, &command_line[name_length]);
 742
 743   the_pipe = popen (command_line, "w");
 744   if (the_pipe == ((FILE *) NULL))
 745     fatal ("cannot open pipe to real mailer");
 746
 747   add_a_stream (the_pipe, pclose);
 748
 749   write_header (the_header);
 750
 751   /* Dump the message itself */
 752
 753   while (!feof (stdin))
 754     {
 755       size = fread (buf, 1, BUFLEN, stdin);
 756       buf[size] = '\0';
 757       put_string (buf);
 758     }
 759
 760   exit (close_the_streams ());
 761 }
 762
 763 #endif /* not MSDOS */
 764 #endif /* not BSD 4.2 (or newer) */