lib-src/b2m.c

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