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, 2009  Free Software Foundation, Inc.
   4
   5 Author: Bill Rozas <jinx@martigny.ai.mit.edu>
   6 (according to ack.texi)
   7
   8 This file is part of GNU Emacs.
   9
  10 GNU Emacs is free software: you can redistribute it and/or modify
  11 it under the terms of the GNU General Public License as published by
  12 the Free Software Foundation, either version 3 of the License, or
  13 (at your option) any later version.
  14
  15 GNU Emacs is distributed in the hope that it will be useful,
  16 but WITHOUT ANY WARRANTY; without even the implied warranty of
  17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18 GNU General Public License for more details.
  19
  20 You should have received a copy of the GNU General Public License
  21 along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
  22
  23
  24 #define _XOPEN_SOURCE 500       /* for cuserid */
  25
  26 #ifdef HAVE_CONFIG_H
  27 #include <config.h>
  28 #endif
  29
  30 #if defined (BSD_SYSTEM) && !defined (USE_FAKEMAIL)
  31 /* This program isnot used in BSD, so just avoid loader complaints.  */
  32 int
  33 main ()
  34 {
  35   return 0;
  36 }
  37 #else /* not BSD 4.2 (or newer) */
  38 #ifdef MSDOS
  39 int
  40 main ()
  41 {
  42   return 0;
  43 }
  44 #else /* not MSDOS */
  45 /* This conditional contains all the rest of the file.  */
  46
  47 /* These are defined in config in some versions. */
  48
  49 #ifdef static
  50 #undef static
  51 #endif
  52
  53 #ifdef WINDOWSNT
  54 #include "ntlib.h"
  55 #endif
  56
  57 #include <stdio.h>
  58 #include <string.h>
  59 #include <ctype.h>
  60 #include <time.h>
  61 #include <pwd.h>
  62
  63 /* This is to declare cuserid.  */
  64 #ifdef HAVE_UNISTD_H
  65 #include <unistd.h>
  66 #endif
  67 \f
  68 /* Type definitions */
  69
  70 #define boolean int
  71 #define true 1
  72 #define false 0
  73
  74 #define TM_YEAR_BASE 1900
  75
  76 /* Nonzero if TM_YEAR is a struct tm's tm_year value that causes
  77    asctime to have well-defined behavior.  */
  78 #ifndef TM_YEAR_IN_ASCTIME_RANGE
  79 # define TM_YEAR_IN_ASCTIME_RANGE(tm_year) \
  80     (1000 - TM_YEAR_BASE <= (tm_year) && (tm_year) <= 9999 - TM_YEAR_BASE)
  81 #endif
  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)
 180      char *s1;
 181 {
 182   error ("%s", s1);
 183   exit (EXIT_FAILURE);
 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");
 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 long
 223 readline (linebuffer, stream)
 224      struct linebuffer *linebuffer;
 225      FILE *stream;
 226 {
 227   char *buffer = linebuffer->buffer;
 228   char *p = linebuffer->buffer;
 229   char *end = p + linebuffer->size;
 230
 231   while (true)
 232     {
 233       int c = getc (stream);
 234       if (p == end)
 235         {
 236           linebuffer->size *= 2;
 237           buffer = ((char *) xrealloc ((long *)buffer, linebuffer->size));
 238           p = buffer + (p - linebuffer->buffer);
 239           end = buffer + linebuffer->size;
 240           linebuffer->buffer = buffer;
 241         }
 242       if (c < 0 || c == '\n')
 243         {
 244           *p = 0;
 245           break;
 246         }
 247       *p++ = c;
 248     }
 249
 250   return p - buffer;
 251 }
 252 \f
 253 /* Extract a colon-terminated keyword from the string FIELD.
 254    Return that keyword as a string stored in a static buffer.
 255    Store the address of the rest of the string into *REST.
 256
 257    If there is no keyword, return NULL and don't alter *REST.  */
 258
 259 char *
 260 get_keyword (field, rest)
 261      register char *field;
 262      char **rest;
 263 {
 264   static char keyword[KEYWORD_SIZE];
 265   register char *ptr;
 266   register int c;
 267
 268   ptr = &keyword[0];
 269   c = (unsigned char) *field++;
 270   if (isspace (c) || c == ':')
 271     return ((char *) NULL);
 272   *ptr++ = (islower (c) ? toupper (c) : c);
 273   while (((c = (unsigned char) *field++) != ':') && ! isspace (c))
 274     *ptr++ = (islower (c) ? toupper (c) : c);
 275   *ptr++ = '\0';
 276   while (isspace (c))
 277     c = (unsigned char) *field++;
 278   if (c != ':')
 279     return ((char *) NULL);
 280   *rest = field;
 281   return &keyword[0];
 282 }
 283
 284 /* Nonzero if the string FIELD starts with a colon-terminated keyword.  */
 285
 286 boolean
 287 has_keyword (field)
 288      char *field;
 289 {
 290   char *ignored;
 291   return (get_keyword (field, &ignored) != ((char *) NULL));
 292 }
 293
 294 /* Store the string FIELD, followed by any lines in THE_LIST,
 295    into the buffer WHERE.
 296    Concatenate lines, putting just a space between them.
 297    Delete everything contained in parentheses.
 298    When a recipient name contains <...>, we discard
 299    everything except what is inside the <...>.
 300
 301    We don't pay attention to overflowing WHERE;
 302    the caller has to make it big enough.  */
 303
 304 char *
 305 add_field (the_list, field, where)
 306      line_list the_list;
 307      register char *field, *where;
 308 {
 309   register char c;
 310   while (true)
 311     {
 312       char *this_recipient_where;
 313       int in_quotes = 0;
 314
 315       *where++ = ' ';
 316       this_recipient_where = where;
 317
 318       while ((c = *field++) != '\0')
 319         {
 320           if (c == '\\')
 321             *where++ = c;
 322           else if (c == '"')
 323             {
 324               in_quotes = ! in_quotes;
 325               *where++ = c;
 326             }
 327           else if (in_quotes)
 328             *where++ = c;
 329           else if (c == '(')
 330             {
 331               while (*field && *field != ')') ++field;
 332               if (! (*field++)) break; /* no close */
 333               continue;
 334             }
 335           else if (c == ',')
 336             {
 337               *where++ = ' ';
 338               /* When we get to the end of one recipient,
 339                  don't discard it if the next one has <...>.  */
 340               this_recipient_where = where;
 341             }
 342           else if (c == '<')
 343             /* Discard everything we got before the `<'.  */
 344             where = this_recipient_where;
 345           else if (c == '>')
 346             /* Discard the rest of this name that follows the `>'.  */
 347             {
 348               while (*field && *field != ',') ++field;
 349               if (! (*field++)) break; /* no comma */
 350               continue;
 351             }
 352           else
 353             *where++ = c;
 354         }
 355       if (the_list == NIL) break;
 356       field = the_list->string;
 357       the_list = the_list->continuation;
 358     }
 359   return where;
 360 }
 361 \f
 362 line_list
 363 make_file_preface ()
 364 {
 365   char *the_string, *temp;
 366   long idiotic_interface;
 367   struct tm *tm;
 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   /* Convert to a string, checking for out-of-range time stamps.
 376      Don't use 'ctime', as that might dump core if the hardware clock
 377      is set to a bizarre value.  */
 378   tm = localtime (&idiotic_interface);
 379   if (! (tm && TM_YEAR_IN_ASCTIME_RANGE (tm->tm_year)
 380          && (the_date = asctime (tm))))
 381     fatal ("current time is out of range");
 382   /* the_date has an unwanted newline at the end */
 383   date_length = strlen (the_date) - 1;
 384   the_date[date_length] = '\0';
 385   temp = cuserid ((char *) NULL);
 386   user_length = strlen (temp);
 387   the_user = alloc_string (user_length + 1);
 388   strcpy (the_user, temp);
 389   the_string = alloc_string (3 + prefix_length
 390                              + user_length
 391                              + date_length);
 392   temp = the_string;
 393   strcpy (temp, FROM_PREFIX);
 394   temp = &temp[prefix_length];
 395   *temp++ = ' ';
 396   strcpy (temp, the_user);
 397   temp = &temp[user_length];
 398   *temp++ = ' ';
 399   strcpy (temp, the_date);
 400   result = new_list ();
 401   result->string = the_string;
 402   result->continuation = ((line_list) NULL);
 403   return result;
 404 }
 405
 406 void
 407 write_line_list (the_list, the_stream)
 408      register line_list the_list;
 409      FILE *the_stream;
 410 {
 411   for ( ;
 412       the_list != ((line_list) NULL) ;
 413       the_list = the_list->continuation)
 414     {
 415       fputs (the_list->string, the_stream);
 416       putc ('\n', the_stream);
 417     }
 418   return;
 419 }
 420 \f
 421 int
 422 close_the_streams ()
 423 {
 424   register stream_list rem;
 425   for (rem = the_streams;
 426        rem != ((stream_list) NULL);
 427        rem = rem->rest_streams)
 428     no_problems = (no_problems &&
 429                    ((*rem->action) (rem->handle) == 0));
 430   the_streams = ((stream_list) NULL);
 431   return (no_problems ? EXIT_SUCCESS : EXIT_FAILURE);
 432 }
 433
 434 void
 435 add_a_stream (the_stream, closing_action)
 436      FILE *the_stream;
 437      int (*closing_action)();
 438 {
 439   stream_list old = the_streams;
 440   the_streams = new_stream ();
 441   the_streams->handle = the_stream;
 442   the_streams->action = closing_action;
 443   the_streams->rest_streams = old;
 444   return;
 445 }
 446
 447 int
 448 my_fclose (the_file)
 449      FILE *the_file;
 450 {
 451   putc ('\n', the_file);
 452   fflush (the_file);
 453   return fclose (the_file);
 454 }
 455
 456 boolean
 457 open_a_file (name)
 458      char *name;
 459 {
 460   FILE *the_stream = fopen (name, "a");
 461   if (the_stream != ((FILE *) NULL))
 462     {
 463       add_a_stream (the_stream, my_fclose);
 464       if (the_user == ((char *) NULL))
 465         file_preface = make_file_preface ();
 466       write_line_list (file_preface, the_stream);
 467       return true;
 468     }
 469   return false;
 470 }
 471
 472 void
 473 put_string (s)
 474      char *s;
 475 {
 476   register stream_list rem;
 477   for (rem = the_streams;
 478        rem != ((stream_list) NULL);
 479        rem = rem->rest_streams)
 480     fputs (s, rem->handle);
 481   return;
 482 }
 483
 484 void
 485 put_line (string)
 486      char *string;
 487 {
 488   register stream_list rem;
 489   for (rem = the_streams;
 490        rem != ((stream_list) NULL);
 491        rem = rem->rest_streams)
 492     {
 493       char *s = string;
 494       int column = 0;
 495
 496       /* Divide STRING into lines.  */
 497       while (*s != 0)
 498         {
 499           char *breakpos;
 500
 501           /* Find the last char that fits.  */
 502           for (breakpos = s; *breakpos && column < 78; ++breakpos)
 503             {
 504               if (*breakpos == '\t')
 505                 column += 8;
 506               else
 507                 column++;
 508             }
 509           /* If we didn't reach end of line, break the line.  */
 510           if (*breakpos)
 511             {
 512               /* Back up to just after the last comma that fits.  */
 513               while (breakpos != s && breakpos[-1] != ',') --breakpos;
 514
 515               if (breakpos == s)
 516                 {
 517                   /* If no comma fits, move past the first address anyway.  */
 518                   while (*breakpos != 0 && *breakpos != ',') ++breakpos;
 519                   if (*breakpos != 0)
 520                     /* Include the comma after it.  */
 521                     ++breakpos;
 522                 }
 523             }
 524           /* Output that much, then break the line.  */
 525           fwrite (s, 1, breakpos - s, rem->handle);
 526           column = 8;
 527
 528           /* Skip whitespace and prepare to print more addresses.  */
 529           s = breakpos;
 530           while (*s == ' ' || *s == '\t') ++s;
 531           if (*s != 0)
 532             fputs ("\n\t", rem->handle);
 533         }
 534       putc ('\n', rem->handle);
 535     }
 536   return;
 537 }
 538 \f
 539 #define mail_error error
 540
 541 /* Handle an FCC field.  FIELD is the text of the first line (after
 542    the header name), and THE_LIST holds the continuation lines if any.
 543    Call open_a_file for each file.  */
 544
 545 void
 546 setup_files (the_list, field)
 547      register line_list the_list;
 548      register char *field;
 549 {
 550   register char *start;
 551   register char c;
 552   while (true)
 553     {
 554       while (((c = *field) != '\0')
 555              && (c == ' '
 556                  || c == '\t'
 557                  || c == ','))
 558         field += 1;
 559       if (c != '\0')
 560         {
 561           start = field;
 562           while (((c = *field) != '\0')
 563                  && c != ' '
 564                  && c != '\t'
 565                  && c != ',')
 566             field += 1;
 567           *field = '\0';
 568           if (!open_a_file (start))
 569             mail_error ("Could not open file %s", start);
 570           *field = c;
 571           if (c != '\0') continue;
 572         }
 573       if (the_list == ((line_list) NULL))
 574         return;
 575       field = the_list->string;
 576       the_list = the_list->continuation;
 577     }
 578 }
 579 \f
 580 /* Compute the total size of all recipient names stored in THE_HEADER.
 581    The result says how big to make the buffer to pass to parse_header.  */
 582
 583 int
 584 args_size (the_header)
 585      header the_header;
 586 {
 587   register header old = the_header;
 588   register line_list rem;
 589   register int size = 0;
 590   do
 591     {
 592       char *field;
 593       register char *keyword = get_keyword (the_header->text->string, &field);
 594       if ((strcmp (keyword, "TO") == 0)
 595           || (strcmp (keyword, "CC") == 0)
 596           || (strcmp (keyword, "BCC") == 0))
 597         {
 598           size += 1 + strlen (field);
 599           for (rem = the_header->text->continuation;
 600                rem != NIL;
 601                rem = rem->continuation)
 602             size += 1 + strlen (rem->string);
 603         }
 604       the_header = the_header->next;
 605     } while (the_header != old);
 606   return size;
 607 }
 608
 609 /* Scan the header described by the lists THE_HEADER,
 610    and put all recipient names into the buffer WHERE.
 611    Precede each recipient name with a space.
 612
 613    Also, if the header has any FCC fields, call setup_files for each one.  */
 614
 615 void
 616 parse_header (the_header, where)
 617      header the_header;
 618      register char *where;
 619 {
 620   register header old = the_header;
 621   do
 622     {
 623       char *field;
 624       register char *keyword = get_keyword (the_header->text->string, &field);
 625       if (strcmp (keyword, "TO") == 0)
 626         where = add_field (the_header->text->continuation, field, where);
 627       else if (strcmp (keyword, "CC") == 0)
 628         where = add_field (the_header->text->continuation, field, where);
 629       else if (strcmp (keyword, "BCC") == 0)
 630         {
 631           where = add_field (the_header->text->continuation, field, where);
 632           the_header->previous->next = the_header->next;
 633           the_header->next->previous = the_header->previous;
 634         }
 635       else if (strcmp (keyword, "FCC") == 0)
 636         setup_files (the_header->text->continuation, field);
 637       the_header = the_header->next;
 638     } while (the_header != old);
 639   *where = '\0';
 640   return;
 641 }
 642 \f
 643 /* Read lines from the input until we get a blank line.
 644    Create a list of `header' objects, one for each header field,
 645    each of which points to a list of `line_list' objects,
 646    one for each line in that field.
 647    Continuation lines are grouped in the headers they continue.  */
 648
 649 header
 650 read_header ()
 651 {
 652   register header the_header = ((header) NULL);
 653   register line_list *next_line = ((line_list *) NULL);
 654
 655   init_linebuffer (&lb);
 656
 657   do
 658     {
 659       long length;
 660       register char *line;
 661
 662       readline (&lb, stdin);
 663       line = lb.buffer;
 664       length = strlen (line);
 665       if (length == 0) break;
 666
 667       if (has_keyword (line))
 668         {
 669           register header old = the_header;
 670           the_header = new_header ();
 671           if (old == ((header) NULL))
 672             {
 673               the_header->next = the_header;
 674               the_header->previous = the_header;
 675             }
 676           else
 677             {
 678               the_header->previous = old;
 679               the_header->next = old->next;
 680               old->next = the_header;
 681             }
 682           next_line = &(the_header->text);
 683         }
 684
 685       if (next_line == ((line_list *) NULL))
 686         {
 687           /* Not a valid header */
 688           exit (EXIT_FAILURE);
 689         }
 690       *next_line = new_list ();
 691       (*next_line)->string = alloc_string (length);
 692       strcpy (((*next_line)->string), line);
 693       next_line = &((*next_line)->continuation);
 694       *next_line = NIL;
 695
 696     } while (true);
 697
 698   if (! the_header)
 699     fatal ("input message has no header");
 700   return the_header->next;
 701 }
 702 \f
 703 void
 704 write_header (the_header)
 705      header the_header;
 706 {
 707   register header old = the_header;
 708   do
 709     {
 710       register line_list the_list;
 711       for (the_list = the_header->text;
 712            the_list != NIL;
 713            the_list = the_list->continuation)
 714         put_line (the_list->string);
 715       the_header = the_header->next;
 716     } while (the_header != old);
 717   put_line ("");
 718   return;
 719 }
 720 \f
 721 int
 722 main (argc, argv)
 723      int argc;
 724      char **argv;
 725 {
 726   char *command_line;
 727   header the_header;
 728   long name_length;
 729   char *mail_program_name;
 730   char buf[BUFLEN + 1];
 731   register int size;
 732   FILE *the_pipe;
 733
 734   extern char *getenv ();
 735
 736   mail_program_name = getenv ("FAKEMAILER");
 737   if (!(mail_program_name && *mail_program_name))
 738     mail_program_name = MAIL_PROGRAM_NAME;
 739   name_length = strlen (mail_program_name);
 740
 741   my_name = MY_NAME;
 742   the_streams = ((stream_list) NULL);
 743   the_date = ((char *) NULL);
 744   the_user = ((char *) NULL);
 745
 746   the_header = read_header ();
 747   command_line = alloc_string (name_length + args_size (the_header));
 748   strcpy (command_line, mail_program_name);
 749   parse_header (the_header, &command_line[name_length]);
 750
 751   the_pipe = popen (command_line, "w");
 752   if (the_pipe == ((FILE *) NULL))
 753     fatal ("cannot open pipe to real mailer");
 754
 755   add_a_stream (the_pipe, pclose);
 756
 757   write_header (the_header);
 758
 759   /* Dump the message itself */
 760
 761   while (!feof (stdin))
 762     {
 763       size = fread (buf, 1, BUFLEN, stdin);
 764       buf[size] = '\0';
 765       put_string (buf);
 766     }
 767
 768   exit (close_the_streams ());
 769 }
 770
 771 #endif /* not MSDOS */
 772 #endif /* not BSD 4.2 (or newer) */
 773
 774 /* arch-tag: acb0afa6-315a-4c5b-b9e3-def5725c8783
 775    (do not change this comment) */
 776
 777 /* fakemail.c ends here */