numtools

commit 258495d0a32a728ba75d8569df12b7989d731646
parent 76946865659abbf6fb22ab476a2c6075aed14a99
Author: Anders Damsgaard <anders@adamsgaard.dk>
Date:   Wed, 11 May 2022 11:58:44 +0200

randnum(1): use getopt(2) and safe formatting specs

Diffstat:
M
randnum.1
 | 
43
+++++++++++++++++++++----------------------
M
randnum.c
 | 
78
+++++++++++++++++++++++++++++++++++++++++++++++-------------------------------

2 files changed, 68 insertions(+), 53 deletions(-)
diff --git a/randnum.1 b/randnum.1
@@ -6,9 +6,10 @@
 .Nd produces random numbers in a range
 .Sh SYNOPSIS
 .Nm
-.Op Fl f Ar fmtstr
-.Op Fl h
-.Op Fl n Ar num
+.Op Fl d Ar delimstr
+.Op Fl n
+.Op Fl N Ar num
+.Op Fl p Ar prec
 .Op Fl s Ar seed
 .Oo
 .Op Ar min_val
@@ -40,19 +41,20 @@ within the same microsecond will produce the same result.
 .Pp
 The options are as follows:
 .Bl -tag -width Ds
-.It Fl f Ar fmtstr
-Formatting string to use as documented in
-.Xr printf 3 .
-When including a format specifier (%..), only use forms that are
-compatible with
-.Vt double
-types.
-The default format string is '%.17g'.
-.It Fl h
-Show usage information.
-.It Fl n Ar num
+.It Fl d Ar delimstr
+Separate output values by
+.Ar delimstr .
+The default delimiter is newlines.
+.It Fl n
+Do not print a newline after the final value.
+.It Fl N num
 Number of random points to generate.
-The default is 1.
+.It Fl p prec
+Print the output values with
+.Ar prec
+digits of precision.
+By default, the output is printed with 17 digits of precision, which is
+full double precision on 64-bit systems.
 .It Fl s Ar seed
 Seed the pseudo-random number generator with this value, which is used
 to generate reproducable binning.
@@ -63,13 +65,10 @@ Due to the randomness, your output may differ:
 .Dl $ randnum
 .Dl 0.38385568287140259
 .Pp
-Generate five points in the range [-10;10[ and print with three significant digits:
-.Dl $ randnum -n 5 -f '%.3g' -- -10 10
-.Dl -4.16
-.Dl -3.36
-.Dl -5.8
-.Dl -2.31
-.Dl 4.4
+Generate five points in the range [-10;10[ and print with three
+significant digits seperated by spaces:
+.Dl $ randnum -N 5 -p 3 -d ' ' -- -10 10
+.Dl -5.52 -5.5 -3.88 3.49 -3.11
 .Sh SEE ALSO
 .Xr randcounts 1 ,
 .Xr range 1 ,
diff --git a/randnum.c b/randnum.c
@@ -4,59 +4,72 @@
 #include <limits.h>
 #include <string.h>
 #include <math.h>
+#include <unistd.h>
 #include <sys/time.h>
 
-#include "arg.h"
 #include "util.h"
 
-char *argv0;
-
 static void
 usage(void)
 {
-	errx(1, "usage: %s [-f fmtstr] [-h] [-n num] [-s seed] "
-	        "[[min_val] max_val]\n", argv0);
+	errx(1, "usage: randnum [-d delimstr] [-n] [-N num] "
+	        "[-p prec] [-s seed] "
+	        "[[min_val] max_val]\n");
 }
 
 int
 main(int argc, char *argv[])
 {
-	int i, ret, s = 0;
+	int i, ret, ch, s = 0, prec = 17, finalnl = 1;
 	long j, seed, n = 1;
 	double val, minv = 0.0, maxv = 1.0;
-	char fmtstr[PATH_MAX] = "%.17g";
+	char *delimstr = "\n";
+	const char *errstr;
 	struct timeval t1;
 
 	if (pledge("stdio", NULL) == -1)
 		err(2, "pledge");
 
-	ARGBEGIN {
-	case 'f':
-		ret = snprintf(fmtstr, sizeof(fmtstr), "%s", EARGF(usage()));
-		if (ret < 0 || (size_t)ret >= sizeof(fmtstr))
-			errx(1, "%s: could not write fmtstr", __func__);
-		break;
-	case 'h':
-		usage();
-		break;
-	case 'n':
-		n = atoi(EARGF(usage()));
-		break;
-	case 's':
-		s = 1;
-		seed = atol(EARGF(usage()));
-		break;
-	default:
-		usage();
-	} ARGEND;
+	while ((ch = getopt(argc, argv, "d:nN:p:s:")) != -1) {
+		switch (ch) {
+		case 'd':
+			delimstr = optarg;
+			break;
+		case 'n':
+			finalnl = 0;
+			break;
+		case 'N':
+			n = strtonum(optarg, 0, LONG_MAX, &errstr);
+			if (errstr != NULL)
+				errx(1, "bad num value, %s: %s", errstr, optarg);
+			break;
+		case 'p':
+			prec = strtonum(optarg, -10, INT_MAX, &errstr);
+			if (errstr != NULL)
+				errx(1, "bad precision value, %s: %s", errstr, optarg);
+			break;
+		case 's':
+			seed = strtonum(optarg, 0, INT_MAX, &errstr);
+			if (errstr != NULL)
+				errx(1, "bad seed value, %s: %s", errstr, optarg);
+			break;
+		default:
+			usage();
+		}
+	}
+	argc -= optind;
+	argv += optind;
 
 	if (argc > 2)
 		usage();
 	else if (argc == 2) {
-		minv = atof(argv[0]);
-		maxv = atof(argv[1]);
+		if (!sscanf(argv[0], "%lf", &minv))
+			errx(1, "bad minv value: %s", argv[0]);
+		if (!sscanf(argv[1], "%lf", &maxv))
+			errx(1, "bad maxv value: %s", argv[1]);
 	} else if (argc == 1)
-		maxv = atof(argv[0]);
+		if (!sscanf(argv[0], "%lf", &maxv))
+			errx(1, "bad maxv value: %s", argv[0]);
 
 	if (s)
 #ifdef __OpenBSD__
@@ -70,9 +83,12 @@ main(int argc, char *argv[])
 #endif
 
 	for (i = 0; i < n; i++) {
-		printf(fmtstr, drand48() * (maxv - minv) + minv);
-		putchar('\n');
+		printf("%.*g", prec, drand48() * (maxv - minv) + minv);
+		if (i < n - 1)
+			fputs(delimstr, stdout);
 	}
+	if (finalnl)
+		putchar('\n');
 
 	return 0;
 }