1/* sendmail-like interface to /bin/mail for system V,
2   Copyright (C) 1985, 1994, 1999, 2001, 2002, 2003, 2004,
3                 2005, 2006, 2007  Free Software Foundation, Inc.
4
5This file is part of GNU Emacs.
6
7GNU Emacs is free software; you can redistribute it and/or modify
8it under the terms of the GNU General Public License as published by
9the Free Software Foundation; either version 2, or (at your option)
10any later version.
11
12GNU Emacs is distributed in the hope that it will be useful,
13but WITHOUT ANY WARRANTY; without even the implied warranty of
14MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15GNU General Public License for more details.
16
17You should have received a copy of the GNU General Public License
18along with GNU Emacs; see the file COPYING.  If not, write to
19the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
20Boston, 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.  */
31int
32main ()
33{
34  return 0;
35}
36#else /* not BSD 4.2 (or newer) */
37#ifdef MSDOS
38int
39main ()
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
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
84struct line_record
85{
86  char *string;
87  struct line_record *continuation;
88};
89typedef struct line_record *line_list;
90
91struct header_record
92{
93  line_list text;
94  struct header_record *next;
95  struct header_record *previous;
96};
97typedef struct header_record *header;
98
99struct stream_record
100{
101  FILE *handle;
102  int (*action)();
103  struct stream_record *rest_streams;
104};
105typedef 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
112struct linebuffer
113{
114  long size;
115  char *buffer;
116};
117
118struct 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
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
142static char *my_name;
143static char *the_date;
144static char *the_user;
145static line_list file_preface;
146static stream_list the_streams;
147static boolean no_problems = true;
148
149extern FILE *popen ();
150extern int fclose (), pclose ();
151
152#ifdef CURRENT_USER
153extern struct passwd *getpwuid ();
154extern unsigned short geteuid ();
155static struct passwd *my_entry;
156#define cuserid(s)				\
157(my_entry = getpwuid (((int) geteuid ())),	\
158 my_entry->pw_name)
159#endif
160
161/* Utilities */
162
163/* Print error message.  `s1' is printf control string, `s2' is arg for it. */
164
165static void
166error (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
177static void
178fatal (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
187static long *
188xmalloc (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
197static long *
198xrealloc (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
208/* Initialize a linebuffer for use */
209
210void
211init_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
221long
222readline (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
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
258char *
259get_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
285boolean
286has_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
303char *
304add_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
361line_list
362make_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
405void
406write_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
420int
421close_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
433void
434add_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
446int
447my_fclose (the_file)
448     FILE *the_file;
449{
450  putc ('\n', the_file);
451  fflush (the_file);
452  return fclose (the_file);
453}
454
455boolean
456open_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
471void
472put_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
483void
484put_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
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
544void
545setup_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
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
582int
583args_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
614void
615parse_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
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
648header
649read_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
702void
703write_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
720int
721main (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 */
777