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