123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138 |
- /* seq.c - Count from first to last, by increment.
- *
- * Copyright 2006 Rob Landley <rob@landley.net>
- *
- * http://refspecs.linuxfoundation.org/LSB_4.1.0/LSB-Core-generic/LSB-Core-generic/seq.html
- USE_SEQ(NEWTOY(seq, "<1>3?f:s:w[!fw]", TOYFLAG_USR|TOYFLAG_BIN))
- config SEQ
- bool "seq"
- depends on TOYBOX_FLOAT
- default y
- help
- usage: seq [-w|-f fmt_str] [-s sep_str] [first] [increment] last
- Count from first to last, by increment. Omitted arguments default
- to 1. Two arguments are used as first and last. Arguments can be
- negative or floating point.
- -f Use fmt_str as a printf-style floating point format string
- -s Use sep_str as separator, default is a newline character
- -w Pad to equal width with leading zeroes
- */
- #define FOR_seq
- #include "toys.h"
- GLOBALS(
- char *s, *f;
- int precision, buflen;
- )
- // Ensure there's one %f escape with correct attributes
- static void insanitize(char *f)
- {
- char *s = next_printf(f, 0);
- if (!s) error_exit("bad -f no %%f");
- if (-1 == stridx("aAeEfFgG", *s) || (s = next_printf(s, 0)))
- error_exit("bad -f '%s'@%d", f, (int)(s-f+1));
- }
- // Parse a numeric argument setting *prec to the precision of this argument.
- // This reproduces the "1.234e5" precision bug from upstream.
- static double parsef(char *s)
- {
- char *dp = strchr(s, '.');
- if (dp++) TT.precision = maxof(TT.precision, strcspn(dp, "eE"));
- return xstrtod(s);
- }
- // fast integer conversion to decimal string
- // TODO move to lib?
- static char *itoa(char *s, int i)
- {
- char buf[16], *ff = buf;
- unsigned n = i;
- if (i<0) {
- *s++ = '-';
- n = -i;
- }
- do *ff++ = '0'+n%10; while ((n /= 10));
- do *s++ = *--ff; while (ff>buf);
- *s++ = '\n';
- return s;
- }
- static char *flush_toybuf(char *ss)
- {
- if (ss-toybuf<TT.buflen) return ss;
- xwrite(1, toybuf, ss-toybuf);
- return toybuf;
- }
- void seq_main(void)
- {
- char fbuf[32], *ss;
- double first = 1, increment = 1, last, dd;
- int ii, inc = 1, len, slen;
- // parse arguments
- if (!TT.s) TT.s = "\n";
- switch (toys.optc) {
- case 3: increment = parsef(toys.optargs[1]);
- case 2: first = parsef(*toys.optargs);
- default: last = parsef(toys.optargs[toys.optc-1]);
- }
- // measure arguments
- if (FLAG(f)) insanitize(TT.f);
- for (ii = len = 0; ii<3; ii++) {
- dd = (double []){first, increment, last}[ii];
- len = maxof(len, snprintf(0, 0, "%.*f", TT.precision, fabs(dd)));
- if (ii == 2) dd += increment;
- slen = dd;
- if (dd != slen) inc = 0;
- }
- if (!FLAG(f)) sprintf(TT.f = fbuf, "%%0%d.%df", len, TT.precision);
- TT.buflen = sizeof(toybuf) - 32 - len - TT.precision - strlen(TT.s);
- if (TT.buflen<0) error_exit("bad -s");
- // fast path: when everything fits in an int with no flags.
- if (!toys.optflags && inc) {
- ii = first;
- len = last;
- inc = increment;
- ss = toybuf;
- if (inc>0) for (; ii<=len; ii += inc)
- ss = flush_toybuf(itoa(ss, ii));
- else if (inc<0) for (; ii>=len; ii += inc)
- ss = flush_toybuf(itoa(ss, ii));
- if (ss != toybuf) xwrite(1, toybuf, ss-toybuf);
- return;
- }
- // Other implementations output nothing if increment is 0 and first > last,
- // but loop forever if first < last or even first == last. We output
- // nothing for all three, if you want endless output use "yes".
- if (!increment) return;
- // Slow path, floating point and fancy sprintf() patterns
- for (ii = 0, ss = toybuf;; ii++) {
- // Multiply to avoid accumulating rounding errors from increment.
- dd = first+ii*increment;
- if ((increment<0 && dd<last) || (increment>0 && dd>last)) break;
- if (ii) ss = flush_toybuf(stpcpy(ss, TT.s));
- ss += sprintf(ss, TT.f, dd);
- }
- *ss++ = '\n';
- xwrite(1, toybuf, ss-toybuf);
- }
|