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, 2010  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)(FILE *);
 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 (const char *, const char *);
 151 extern int fclose (FILE *), pclose (FILE *);
 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 (char *s1, char *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 (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 (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 (long int *ptr, int size)
 197 {
 198   long *result = (long *) realloc (ptr, ((unsigned) size));
 199   if (result == ((long *) NULL))
 200     fatal ("virtual memory exhausted");
 201   return result;
 202 }
 203 \f
 204 /* Initialize a linebuffer for use */
 205
 206 void
 207 init_linebuffer (struct linebuffer *linebuffer)
 208 {
 209   linebuffer->size = INITIAL_LINE_SIZE;
 210   linebuffer->buffer = ((char *) xmalloc (INITIAL_LINE_SIZE));
 211 }
 212
 213 /* Read a line of text from `stream' into `linebuffer'.
 214    Return the length of the line.  */
 215
 216 long
 217 readline (struct linebuffer *linebuffer, FILE *stream)
 218 {
 219   char *buffer = linebuffer->buffer;
 220   char *p = linebuffer->buffer;
 221   char *end = p + linebuffer->size;
 222
 223   while (true)
 224     {
 225       int c = getc (stream);
 226       if (p == end)
 227         {
 228           linebuffer->size *= 2;
 229           buffer = ((char *) xrealloc ((long *)buffer, linebuffer->size));
 230           p = buffer + (p - linebuffer->buffer);
 231           end = buffer + linebuffer->size;
 232           linebuffer->buffer = buffer;
 233         }
 234       if (c < 0 || c == '\n')
 235         {
 236           *p = 0;
 237           break;
 238         }
 239       *p++ = c;
 240     }
 241
 242   return p - buffer;
 243 }
 244 \f
 245 /* Extract a colon-terminated keyword from the string FIELD.
 246    Return that keyword as a string stored in a static buffer.
 247    Store the address of the rest of the string into *REST.
 248
 249    If there is no keyword, return NULL and don't alter *REST.  */
 250
 251 char *
 252 get_keyword (register char *field, char **rest)
 253 {
 254   static char keyword[KEYWORD_SIZE];
 255   register char *ptr;
 256   register int c;
 257
 258   ptr = &keyword[0];
 259   c = (unsigned char) *field++;
 260   if (isspace (c) || c == ':')
 261     return ((char *) NULL);
 262   *ptr++ = (islower (c) ? toupper (c) : c);
 263   while (((c = (unsigned char) *field++) != ':') && ! isspace (c))
 264     *ptr++ = (islower (c) ? toupper (c) : c);
 265   *ptr++ = '\0';
 266   while (isspace (c))
 267     c = (unsigned char) *field++;
 268   if (c != ':')
 269     return ((char *) NULL);
 270   *rest = field;
 271   return &keyword[0];
 272 }
 273
 274 /* Nonzero if the string FIELD starts with a colon-terminated keyword.  */
 275
 276 boolean
 277 has_keyword (char *field)
 278 {
 279   char *ignored;
 280   return (get_keyword (field, &ignored) != ((char *) NULL));
 281 }
 282
 283 /* Store the string FIELD, followed by any lines in THE_LIST,
 284    into the buffer WHERE.
 285    Concatenate lines, putting just a space between them.
 286    Delete everything contained in parentheses.
 287    When a recipient name contains <...>, we discard
 288    everything except what is inside the <...>.
 289
 290    We don't pay attention to overflowing WHERE;
 291    the caller has to make it big enough.  */
 292
 293 char *
 294 add_field (line_list the_list, register char *field, register char *where)
 295 {
 296   register char c;
 297   while (true)
 298     {
 299       char *this_recipient_where;
 300       int in_quotes = 0;
 301
 302       *where++ = ' ';
 303       this_recipient_where = where;
 304
 305       while ((c = *field++) != '\0')
 306         {
 307           if (c == '\\')
 308             *where++ = c;
 309           else if (c == '"')
 310             {
 311               in_quotes = ! in_quotes;
 312               *where++ = c;
 313             }
 314           else if (in_quotes)
 315             *where++ = c;
 316           else if (c == '(')
 317             {
 318               while (*field && *field != ')') ++field;
 319               if (! (*field++)) break; /* no close */
 320               continue;
 321             }
 322           else if (c == ',')
 323             {
 324               *where++ = ' ';
 325               /* When we get to the end of one recipient,
 326                  don't discard it if the next one has <...>.  */
 327               this_recipient_where = where;
 328             }
 329           else if (c == '<')
 330             /* Discard everything we got before the `<'.  */
 331             where = this_recipient_where;
 332           else if (c == '>')
 333             /* Discard the rest of this name that follows the `>'.  */
 334             {
 335               while (*field && *field != ',') ++field;
 336               if (! (*field++)) break; /* no comma */
 337               continue;
 338             }
 339           else
 340             *where++ = c;
 341         }
 342       if (the_list == NIL) break;
 343       field = the_list->string;
 344       the_list = the_list->continuation;
 345     }
 346   return where;
 347 }
 348 \f
 349 line_list
 350 make_file_preface (void)
 351 {
 352   char *the_string, *temp;
 353   long idiotic_interface;
 354   struct tm *tm;
 355   long prefix_length;
 356   long user_length;
 357   long date_length;
 358   line_list result;
 359
 360   prefix_length = strlen (FROM_PREFIX);
 361   time (&idiotic_interface);
 362   /* Convert to a string, checking for out-of-range time stamps.
 363      Don't use 'ctime', as that might dump core if the hardware clock
 364      is set to a bizarre value.  */
 365   tm = localtime (&idiotic_interface);
 366   if (! (tm && TM_YEAR_IN_ASCTIME_RANGE (tm->tm_year)
 367          && (the_date = asctime (tm))))
 368     fatal ("current time is out of range");
 369   /* the_date has an unwanted newline at the end */
 370   date_length = strlen (the_date) - 1;
 371   the_date[date_length] = '\0';
 372   temp = cuserid ((char *) NULL);
 373   user_length = strlen (temp);
 374   the_user = alloc_string (user_length + 1);
 375   strcpy (the_user, temp);
 376   the_string = alloc_string (3 + prefix_length
 377                              + user_length
 378                              + date_length);
 379   temp = the_string;
 380   strcpy (temp, FROM_PREFIX);
 381   temp = &temp[prefix_length];
 382   *temp++ = ' ';
 383   strcpy (temp, the_user);
 384   temp = &temp[user_length];
 385   *temp++ = ' ';
 386   strcpy (temp, the_date);
 387   result = new_list ();
 388   result->string = the_string;
 389   result->continuation = ((line_list) NULL);
 390   return result;
 391 }
 392
 393 void
 394 write_line_list (register line_list the_list, FILE *the_stream)
 395 {
 396   for ( ;
 397       the_list != ((line_list) NULL) ;
 398       the_list = the_list->continuation)
 399     {
 400       fputs (the_list->string, the_stream);
 401       putc ('\n', the_stream);
 402     }
 403   return;
 404 }
 405 \f
 406 int
 407 close_the_streams (void)
 408 {
 409   register stream_list rem;
 410   for (rem = the_streams;
 411        rem != ((stream_list) NULL);
 412        rem = rem->rest_streams)
 413     no_problems = (no_problems &&
 414                    ((*rem->action) (rem->handle) == 0));
 415   the_streams = ((stream_list) NULL);
 416   return (no_problems ? EXIT_SUCCESS : EXIT_FAILURE);
 417 }
 418
 419 void
 420 add_a_stream (FILE *the_stream, int (*closing_action) (FILE *))
 421 {
 422   stream_list old = the_streams;
 423   the_streams = new_stream ();
 424   the_streams->handle = the_stream;
 425   the_streams->action = closing_action;
 426   the_streams->rest_streams = old;
 427   return;
 428 }
 429
 430 int
 431 my_fclose (FILE *the_file)
 432 {
 433   putc ('\n', the_file);
 434   fflush (the_file);
 435   return fclose (the_file);
 436 }
 437
 438 boolean
 439 open_a_file (char *name)
 440 {
 441   FILE *the_stream = fopen (name, "a");
 442   if (the_stream != ((FILE *) NULL))
 443     {
 444       add_a_stream (the_stream, my_fclose);
 445       if (the_user == ((char *) NULL))
 446         file_preface = make_file_preface ();
 447       write_line_list (file_preface, the_stream);
 448       return true;
 449     }
 450   return false;
 451 }
 452
 453 void
 454 put_string (char *s)
 455 {
 456   register stream_list rem;
 457   for (rem = the_streams;
 458        rem != ((stream_list) NULL);
 459        rem = rem->rest_streams)
 460     fputs (s, rem->handle);
 461   return;
 462 }
 463
 464 void
 465 put_line (char *string)
 466 {
 467   register stream_list rem;
 468   for (rem = the_streams;
 469        rem != ((stream_list) NULL);
 470        rem = rem->rest_streams)
 471     {
 472       char *s = string;
 473       int column = 0;
 474
 475       /* Divide STRING into lines.  */
 476       while (*s != 0)
 477         {
 478           char *breakpos;
 479
 480           /* Find the last char that fits.  */
 481           for (breakpos = s; *breakpos && column < 78; ++breakpos)
 482             {
 483               if (*breakpos == '\t')
 484                 column += 8;
 485               else
 486                 column++;
 487             }
 488           /* If we didn't reach end of line, break the line.  */
 489           if (*breakpos)
 490             {
 491               /* Back up to just after the last comma that fits.  */
 492               while (breakpos != s && breakpos[-1] != ',') --breakpos;
 493
 494               if (breakpos == s)
 495                 {
 496                   /* If no comma fits, move past the first address anyway.  */
 497                   while (*breakpos != 0 && *breakpos != ',') ++breakpos;
 498                   if (*breakpos != 0)
 499                     /* Include the comma after it.  */
 500                     ++breakpos;
 501                 }
 502             }
 503           /* Output that much, then break the line.  */
 504           fwrite (s, 1, breakpos - s, rem->handle);
 505           column = 8;
 506
 507           /* Skip whitespace and prepare to print more addresses.  */
 508           s = breakpos;
 509           while (*s == ' ' || *s == '\t') ++s;
 510           if (*s != 0)
 511             fputs ("\n\t", rem->handle);
 512         }
 513       putc ('\n', rem->handle);
 514     }
 515   return;
 516 }
 517 \f
 518 #define mail_error error
 519
 520 /* Handle an FCC field.  FIELD is the text of the first line (after
 521    the header name), and THE_LIST holds the continuation lines if any.
 522    Call open_a_file for each file.  */
 523
 524 void
 525 setup_files (register line_list the_list, register char *field)
 526 {
 527   register char *start;
 528   register char c;
 529   while (true)
 530     {
 531       while (((c = *field) != '\0')
 532              && (c == ' '
 533                  || c == '\t'
 534                  || c == ','))
 535         field += 1;
 536       if (c != '\0')
 537         {
 538           start = field;
 539           while (((c = *field) != '\0')
 540                  && c != ' '
 541                  && c != '\t'
 542                  && c != ',')
 543             field += 1;
 544           *field = '\0';
 545           if (!open_a_file (start))
 546             mail_error ("Could not open file %s", start);
 547           *field = c;
 548           if (c != '\0') continue;
 549         }
 550       if (the_list == ((line_list) NULL))
 551         return;
 552       field = the_list->string;
 553       the_list = the_list->continuation;
 554     }
 555 }
 556 \f
 557 /* Compute the total size of all recipient names stored in THE_HEADER.
 558    The result says how big to make the buffer to pass to parse_header.  */
 559
 560 int
 561 args_size (header the_header)
 562 {
 563   register header old = the_header;
 564   register line_list rem;
 565   register int size = 0;
 566   do
 567     {
 568       char *field;
 569       register char *keyword = get_keyword (the_header->text->string, &field);
 570       if ((strcmp (keyword, "TO") == 0)
 571           || (strcmp (keyword, "CC") == 0)
 572           || (strcmp (keyword, "BCC") == 0))
 573         {
 574           size += 1 + strlen (field);
 575           for (rem = the_header->text->continuation;
 576                rem != NIL;
 577                rem = rem->continuation)
 578             size += 1 + strlen (rem->string);
 579         }
 580       the_header = the_header->next;
 581     } while (the_header != old);
 582   return size;
 583 }
 584
 585 /* Scan the header described by the lists THE_HEADER,
 586    and put all recipient names into the buffer WHERE.
 587    Precede each recipient name with a space.
 588
 589    Also, if the header has any FCC fields, call setup_files for each one.  */
 590
 591 void
 592 parse_header (header the_header, register char *where)
 593 {
 594   register header old = the_header;
 595   do
 596     {
 597       char *field;
 598       register char *keyword = get_keyword (the_header->text->string, &field);
 599       if (strcmp (keyword, "TO") == 0)
 600         where = add_field (the_header->text->continuation, field, where);
 601       else if (strcmp (keyword, "CC") == 0)
 602         where = add_field (the_header->text->continuation, field, where);
 603       else if (strcmp (keyword, "BCC") == 0)
 604         {
 605           where = add_field (the_header->text->continuation, field, where);
 606           the_header->previous->next = the_header->next;
 607           the_header->next->previous = the_header->previous;
 608         }
 609       else if (strcmp (keyword, "FCC") == 0)
 610         setup_files (the_header->text->continuation, field);
 611       the_header = the_header->next;
 612     } while (the_header != old);
 613   *where = '\0';
 614   return;
 615 }
 616 \f
 617 /* Read lines from the input until we get a blank line.
 618    Create a list of `header' objects, one for each header field,
 619    each of which points to a list of `line_list' objects,
 620    one for each line in that field.
 621    Continuation lines are grouped in the headers they continue.  */
 622
 623 header
 624 read_header (void)
 625 {
 626   register header the_header = ((header) NULL);
 627   register line_list *next_line = ((line_list *) NULL);
 628
 629   init_linebuffer (&lb);
 630
 631   do
 632     {
 633       long length;
 634       register char *line;
 635
 636       readline (&lb, stdin);
 637       line = lb.buffer;
 638       length = strlen (line);
 639       if (length == 0) break;
 640
 641       if (has_keyword (line))
 642         {
 643           register header old = the_header;
 644           the_header = new_header ();
 645           if (old == ((header) NULL))
 646             {
 647               the_header->next = the_header;
 648               the_header->previous = the_header;
 649             }
 650           else
 651             {
 652               the_header->previous = old;
 653               the_header->next = old->next;
 654               old->next = the_header;
 655             }
 656           next_line = &(the_header->text);
 657         }
 658
 659       if (next_line == ((line_list *) NULL))
 660         {
 661           /* Not a valid header */
 662           exit (EXIT_FAILURE);
 663         }
 664       *next_line = new_list ();
 665       (*next_line)->string = alloc_string (length);
 666       strcpy (((*next_line)->string), line);
 667       next_line = &((*next_line)->continuation);
 668       *next_line = NIL;
 669
 670     } while (true);
 671
 672   if (! the_header)
 673     fatal ("input message has no header");
 674   return the_header->next;
 675 }
 676 \f
 677 void
 678 write_header (header the_header)
 679 {
 680   register header old = the_header;
 681   do
 682     {
 683       register line_list the_list;
 684       for (the_list = the_header->text;
 685            the_list != NIL;
 686            the_list = the_list->continuation)
 687         put_line (the_list->string);
 688       the_header = the_header->next;
 689     } while (the_header != old);
 690   put_line ("");
 691   return;
 692 }
 693 \f
 694 int
 695 main (int argc, char **argv)
 696 {
 697   char *command_line;
 698   header the_header;
 699   long name_length;
 700   char *mail_program_name;
 701   char buf[BUFLEN + 1];
 702   register int size;
 703   FILE *the_pipe;
 704
 705   extern char *getenv (const char *);
 706
 707   mail_program_name = getenv ("FAKEMAILER");
 708   if (!(mail_program_name && *mail_program_name))
 709     mail_program_name = MAIL_PROGRAM_NAME;
 710   name_length = strlen (mail_program_name);
 711
 712   my_name = MY_NAME;
 713   the_streams = ((stream_list) NULL);
 714   the_date = ((char *) NULL);
 715   the_user = ((char *) NULL);
 716
 717   the_header = read_header ();
 718   command_line = alloc_string (name_length + args_size (the_header));
 719   strcpy (command_line, mail_program_name);
 720   parse_header (the_header, &command_line[name_length]);
 721
 722   the_pipe = popen (command_line, "w");
 723   if (the_pipe == ((FILE *) NULL))
 724     fatal ("cannot open pipe to real mailer");
 725
 726   add_a_stream (the_pipe, pclose);
 727
 728   write_header (the_header);
 729
 730   /* Dump the message itself */
 731
 732   while (!feof (stdin))
 733     {
 734       size = fread (buf, 1, BUFLEN, stdin);
 735       buf[size] = '\0';
 736       put_string (buf);
 737     }
 738
 739   exit (close_the_streams ());
 740 }
 741
 742 #endif /* not MSDOS */
 743 #endif /* not BSD 4.2 (or newer) */
 744
 745 /* arch-tag: acb0afa6-315a-4c5b-b9e3-def5725c8783
 746    (do not change this comment) */
 747
 748 /* fakemail.c ends here */