1 /* vi: set sw=4 ts=4: */
3 * seq implementation for busybox
5 * Copyright (C) 2004, Glenn McGrath
7 * Licensed under GPLv2, see file LICENSE in this source tree.
10 //config: bool "seq (3.6 kb)"
13 //config: print a sequence of numbers
15 //applet:IF_SEQ(APPLET_NOFORK(seq, seq, BB_DIR_USR_BIN, BB_SUID_DROP, seq))
17 //kbuild:lib-$(CONFIG_SEQ) += seq.o
19 //usage:#define seq_trivial_usage
20 //usage: "[-w] [-s SEP] [FIRST [INC]] LAST"
21 //usage:#define seq_full_usage "\n\n"
22 //usage: "Print numbers from FIRST to LAST, in steps of INC.\n"
23 //usage: "FIRST, INC default to 1.\n"
24 //usage: "\n -w Pad to last with leading zeros"
25 //usage: "\n -s SEP String separator"
29 /* This is a NOFORK applet. Be very careful! */
31 int seq_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
32 int seq_main(int argc, char **argv)
38 double first, last, increment, v;
42 const char *sep, *opt_s = "\n";
45 #if ENABLE_LOCALE_SUPPORT
46 /* Undo busybox.c: on input, we want to use dot
47 * as fractional separator, regardless of current locale */
48 setlocale(LC_NUMERIC, "C");
51 opt = getopt32(argv, "+ws:", &opt_s);
54 first = increment = 1;
59 increment = strtod(argv[1], &pp);
62 first = strtod(argv[0], &pp);
65 last = strtod(argv[argc-1], &pp);
66 if (!errno && *pp == '\0')
72 #if ENABLE_LOCALE_SUPPORT
73 setlocale(LC_NUMERIC, "");
76 /* Last checked to be compatible with: coreutils-6.10 */
80 char *dot = strchrnul(*argv, '.');
81 int w = (dot - *argv);
88 /* Why do the above _before_ frac check below?
89 * Try "seq 1 2.0" and "seq 1.0 2.0":
90 * coreutils never pay attention to the number
91 * of fractional digits in last arg. */
98 width += frac_part + 1;
106 while (increment >= 0 ? v <= last : v >= last) {
107 if (printf("%s%0*.*f", sep, width, frac_part, v) < 0)
108 break; /* I/O error, bail out (yes, this really happens) */
110 /* v += increment; - would accumulate floating point errors */
112 v = first + n * increment;
114 if (n) /* if while loop executed at least once */