1/*
2 * b2m - a filter for Babyl -> Unix mail files
3 * The copyright on this file has been disclaimed.
4 *
5 * usage:	b2m < babyl > mailbox
6 *
7 * I find this useful whenever I have to use a
8 * system which - shock horror! - doesn't run
9 * GNU Emacs. At least now I can read all my
10 * GNU Emacs Babyl format mail files!
11 *
12 * it's not much but it's free!
13 *
14 *   Ed Wilkinson
15 *   E.Wilkinson@massey.ac.nz
16 *   Mon Nov 7 15:54:06 PDT 1988
17 */
18
19/* Made conformant to the GNU coding standards January, 1995
20   by Francesco Potorti` <pot@cnuce.cnr.it>. */
21
22#ifdef HAVE_CONFIG_H
23#include <config.h>
24/* On some systems, Emacs defines static as nothing for the sake
25   of unexec.  We don't want that here since we don't use unexec. */
26#undef static
27#endif
28
29#include <stdio.h>
30#include <time.h>
31#include <sys/types.h>
32#include <getopt.h>
33#ifdef MSDOS
34#include <fcntl.h>
35#endif
36
37#undef TRUE
38#define TRUE	1
39#undef FALSE
40#define FALSE	0
41
42#define streq(s,t)	(strcmp (s, t) == 0)
43#define strneq(s,t,n)	(strncmp (s, t, n) == 0)
44
45typedef int logical;
46
47#define TM_YEAR_BASE 1900
48
49/* Nonzero if TM_YEAR is a struct tm's tm_year value that causes
50   asctime to have well-defined behavior.  */
51#ifndef TM_YEAR_IN_ASCTIME_RANGE
52# define TM_YEAR_IN_ASCTIME_RANGE(tm_year) \
53    (1000 - TM_YEAR_BASE <= (tm_year) && (tm_year) <= 9999 - TM_YEAR_BASE)
54#endif
55
56/*
57 * A `struct linebuffer' is a structure which holds a line of text.
58 * `readline' reads a line from a stream into a linebuffer and works
59 * regardless of the length of the line.
60 */
61struct linebuffer
62{
63  long size;
64  char *buffer;
65};
66
67extern char *strtok();
68
69long *xmalloc (), *xrealloc ();
70char *concat ();
71long readline ();
72void fatal ();
73
74/*
75 * xnew -- allocate storage.  SYNOPSIS: Type *xnew (int n, Type);
76 */
77#define xnew(n, Type)	((Type *) xmalloc ((n) * sizeof (Type)))
78
79
80
81char *progname;
82
83struct option longopts[] =
84{
85  { "help",			no_argument,	   NULL,     'h'   },
86  { "version",			no_argument,	   NULL,     'V'   },
87  { 0 }
88};
89
90extern int optind;
91
92int
93main (argc, argv)
94     int argc;
95     char **argv;
96{
97  logical labels_saved, printing, header;
98  time_t ltoday;
99  struct tm *tm;
100  char *labels, *p, *today;
101  struct linebuffer data;
102
103#ifdef MSDOS
104  _fmode = O_BINARY;		/* all of files are treated as binary files */
105#if __DJGPP__ > 1
106  if (!isatty (fileno (stdout)))
107    setmode (fileno (stdout), O_BINARY);
108  if (!isatty (fileno (stdin)))
109    setmode (fileno (stdin), O_BINARY);
110#else /* not __DJGPP__ > 1 */
111  (stdout)->_flag &= ~_IOTEXT;
112  (stdin)->_flag &= ~_IOTEXT;
113#endif /* not __DJGPP__ > 1 */
114#endif
115  progname = argv[0];
116
117  while (1)
118    {
119      int opt = getopt_long (argc, argv, "hV", longopts, 0);
120      if (opt == EOF)
121	break;
122
123      switch (opt)
124	{
125	case 'V':
126	  printf ("%s (GNU Emacs %s)\n", "b2m", VERSION);
127	  puts ("b2m is in the public domain.");
128	  exit (EXIT_SUCCESS);
129
130	case 'h':
131	  fprintf (stderr, "Usage: %s <babylmailbox >unixmailbox\n", progname);
132	  exit (EXIT_SUCCESS);
133	}
134    }
135
136  if (optind != argc)
137    {
138      fprintf (stderr, "Usage: %s <babylmailbox >unixmailbox\n", progname);
139      exit (EXIT_SUCCESS);
140    }
141
142  labels_saved = printing = header = FALSE;
143  ltoday = time (0);
144  /* Convert to a string, checking for out-of-range time stamps.
145     Don't use 'ctime', as that might dump core if the hardware clock
146     is set to a bizarre value.  */
147  tm = localtime (&ltoday);
148  if (! (tm && TM_YEAR_IN_ASCTIME_RANGE (tm->tm_year)
149	 && (today = asctime (tm))))
150    fatal ("current time is out of range");
151  data.size = 200;
152  data.buffer = xnew (200, char);
153
154  if (readline (&data, stdin) == 0
155      || !strneq (data.buffer, "BABYL OPTIONS:", 14))
156    fatal ("standard input is not a Babyl mailfile.");
157
158  while (readline (&data, stdin) > 0)
159    {
160      if (streq (data.buffer, "*** EOOH ***") && !printing)
161	{
162	  printing = header = TRUE;
163	  printf ("From \"Babyl to mail by %s\" %s", progname, today);
164	  continue;
165	}
166
167      if (data.buffer[0] == '\037')
168	{
169	  if (data.buffer[1] == '\0')
170	    continue;
171	  else if (data.buffer[1] == '\f')
172	    {
173	      /* Save labels. */
174	      readline (&data, stdin);
175	      p = strtok (data.buffer, " ,\r\n\t");
176	      labels = "X-Babyl-Labels: ";
177
178	      while ((p = strtok (NULL, " ,\r\n\t")))
179		labels = concat (labels, p, ", ");
180
181	      p = &labels[strlen (labels) - 2];
182	      if (*p == ',')
183		*p = '\0';
184	      printing = header = FALSE;
185	      labels_saved = TRUE;
186	      continue;
187	    }
188	}
189
190      if ((data.buffer[0] == '\0') && header)
191	{
192	  header = FALSE;
193	  if (labels_saved)
194	    puts (labels);
195	}
196
197      if (printing)
198	puts (data.buffer);
199    }
200
201  return EXIT_SUCCESS;
202}
203
204
205
206/*
207 * Return a newly-allocated string whose contents
208 * concatenate those of s1, s2, s3.
209 */
210char *
211concat (s1, s2, s3)
212     char *s1, *s2, *s3;
213{
214  int len1 = strlen (s1), len2 = strlen (s2), len3 = strlen (s3);
215  char *result = xnew (len1 + len2 + len3 + 1, char);
216
217  strcpy (result, s1);
218  strcpy (result + len1, s2);
219  strcpy (result + len1 + len2, s3);
220  result[len1 + len2 + len3] = '\0';
221
222  return result;
223}
224
225/*
226 * Read a line of text from `stream' into `linebuffer'.
227 * Return the number of characters read from `stream',
228 * which is the length of the line including the newline, if any.
229 */
230long
231readline (linebuffer, stream)
232     struct linebuffer *linebuffer;
233     register FILE *stream;
234{
235  char *buffer = linebuffer->buffer;
236  register char *p = linebuffer->buffer;
237  register char *pend;
238  int chars_deleted;
239
240  pend = p + linebuffer->size;	/* Separate to avoid 386/IX compiler bug.  */
241
242  while (1)
243    {
244      register int c = getc (stream);
245      if (p == pend)
246	{
247	  linebuffer->size *= 2;
248	  buffer = (char *) xrealloc (buffer, linebuffer->size);
249	  p += buffer - linebuffer->buffer;
250	  pend = buffer + linebuffer->size;
251	  linebuffer->buffer = buffer;
252	}
253      if (c == EOF)
254	{
255	  *p = '\0';
256	  chars_deleted = 0;
257	  break;
258	}
259      if (c == '\n')
260	{
261	  if (p > buffer && p[-1] == '\r')
262	    {
263	      *--p = '\0';
264	      chars_deleted = 2;
265	    }
266	  else
267	    {
268	      *p = '\0';
269	      chars_deleted = 1;
270	    }
271	  break;
272	}
273      *p++ = c;
274    }
275
276  return (p - buffer + chars_deleted);
277}
278
279/*
280 * Like malloc but get fatal error if memory is exhausted.
281 */
282long *
283xmalloc (size)
284     unsigned int size;
285{
286  long *result = (long *) malloc (size);
287  if (result == NULL)
288    fatal ("virtual memory exhausted");
289  return result;
290}
291
292long *
293xrealloc (ptr, size)
294     char *ptr;
295     unsigned int size;
296{
297  long *result = (long *) realloc (ptr, size);
298  if (result == NULL)
299    fatal ("virtual memory exhausted");
300  return result;
301}
302
303void
304fatal (message)
305     char *message;
306{
307  fprintf (stderr, "%s: %s\n", progname, message);
308  exit (EXIT_FAILURE);
309}
310
311/* arch-tag: 5a3ad2af-a802-408f-83cc-e7cf5e98653e
312   (do not change this comment) */
313
314/* b2m.c ends here */
315