Rearrange the file tree.

[u/mdw/catacomb] / progs / fibonacci.c

diff --git a/progs/fibonacci.c b/progs/fibonacci.c
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+/* -*-c-*-
+ *
+ * Example Fibonacci number computation
+ *
+ * (c) 2013 Straylight/Edgeware
+ */
+
+/*----- Licensing notice --------------------------------------------------*
+ *
+ * This file is part of Catacomb.
+ *
+ * Catacomb is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Library General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * Catacomb is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with Catacomb; if not, write to the Free
+ * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
+ * MA 02111-1307, USA.
+ */
+
+/*----- Header files ------------------------------------------------------*/
+
+#include "config.h"
+
+#include <ctype.h>
+#include <limits.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+#include <mLib/mdwopt.h>
+#include <mLib/quis.h>
+#include <mLib/report.h>
+
+#include "mpint.h"
+#include "mptext.h"
+
+#include "mp-fibonacci.h"
+
+/*----- Main code ---------------------------------------------------------*/
+
+static void usage(FILE *fp)
+  { pquis(fp, "Usage: $ [-r RADIX] INTEGER\n"); }
+
+static void version(FILE *fp)
+  { pquis(fp, "$, Catacomb version " VERSION "\n"); }
+
+static void help(FILE *fp)
+{
+  version(fp);
+  putc('\n', fp);
+  usage(fp);
+  fputs("\n\
+Prints the Nth Fibonacci number for a given inteer N.  Input may be in\n\
+decimal (the default), octal with preceding zero, hex with preceding `0x',\n\
+or any base N between 2 and 62 inclusive with preceding `N_'.  Output\n\
+may be in any base between 2 and 62; the default is base 10.  For bases\n\
+between 11 and 36 inclusive, lowercase letters of either case are used as\n\
+additional digits with values 10 upwards; lowercase is always used for\n\
+output.  For bases between 37 and 62 inclusive, lowercase letters have\n\
+lower value than uppercase; hence `a' has the value 10, while `A' has the\n\
+value 36.\n\
+\n\
+Options provided:\n\
+\n\
+-h, --help             Display this help message.\n\
+-v, --version          Display the version number.\n\
+-u, --usage            Display a usage message.\n\
+\n\
+-r, --radix=N          Write output in base N.\n\
+", fp);
+}
+
+int main(int argc, char *argv[])
+{
+  long n;
+  int r = 10;
+  char *p;
+  mp *f, *lmin, *lmax, *nn;
+  unsigned fl = 0;
+
+#define f_bogus 1u
+
+  ego(argv[0]);
+
+  for (;;) {
+    static const struct option opt[] = {
+      { "help",                0,              0,      'h' },
+      { "version",     0,              0,      'v' },
+      { "usage",       0,              0,      'u' },
+      { "radix",       OPTF_ARGREQ,    0,      'r' },
+      { 0,             0,              0,      0 }
+    };
+    int i = mdwopt(argc, argv, "hvur:", opt, 0, 0, 0);
+    if (i < 0)
+      break;
+    switch (i) {
+      case 'h':
+       help(stdout);
+       exit(0);
+      case 'v':
+       version(stdout);
+       exit(0);
+      case 'u':
+       usage(stdout);
+       exit(0);
+      case 'r':
+       r = atoi(optarg);
+       if (r < 2 || r > 62)
+         die(EXIT_FAILURE, "bad radix `%s'", optarg);
+       break;
+      default:
+       fl |= f_bogus;
+       break;
+    }
+  }
+
+  if (optind + 1 != argc || (fl & f_bogus)) {
+    usage(stderr);
+    exit(EXIT_FAILURE);
+  }
+  lmin = mp_fromlong(MP_NEW, LONG_MIN);
+  lmax = mp_fromlong(MP_NEW, LONG_MAX);
+  p = argv[optind];
+  while (isspace((unsigned char)*p)) p++;
+  nn = mp_readstring(MP_NEW, argv[optind], &p, 0);
+  while (isspace((unsigned char)*p)) p++;
+  if (!nn || *p || MP_CMP(lmin, >, nn) || MP_CMP(nn, >, lmax))
+    die(EXIT_FAILURE, "bad integer `%s'", argv[optind]);
+  n = mp_tolong(nn);
+  mp_drop(nn); mp_drop(lmin); mp_drop(lmax);
+  f = mp_fibonacci(n);
+  mp_writefile(f, stdout, r);
+  fputc('\n', stdout);
+  mp_drop(f);
+  return (0);
+}
+
+/*----- That's all, folks -------------------------------------------------*/