factor: support "no-argvs" usage

function                                             old     new   delta
factorize_numstr                                       -      72     +72
packed_usage                                       31562   31566      +4
factor_main                                          109     101      -8
------------------------------------------------------------------------------
(add/remove: 1/0 grow/shrink: 1/1 up/down: 76/-8)              Total: 68 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This commit is contained in:
Denys Vlasenko 2017-04-14 14:23:49 +02:00
parent 44c0ab4102
commit 8352b717ce

View File

@ -14,7 +14,7 @@
//kbuild:lib-$(CONFIG_FACTOR) += factor.o
//usage:#define factor_trivial_usage
//usage: "NUMBER..."
//usage: "[NUMBER]..."
//usage:#define factor_full_usage "\n\n"
//usage: "Print prime factors"
@ -165,6 +165,20 @@ static NOINLINE void factorize(wide_t N)
bb_putchar('\n');
}
static void factorize_numstr(const char *numstr)
{
wide_t N;
/* Leading + is ok (coreutils compat) */
if (*numstr == '+')
numstr++;
N = bb_strtoull(numstr, NULL, 10);
if (errno)
bb_show_usage();
printf("%llu:", N);
factorize(N);
}
int factor_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int factor_main(int argc UNUSED_PARAM, char **argv)
{
@ -173,24 +187,32 @@ int factor_main(int argc UNUSED_PARAM, char **argv)
//argv += optind;
argv++;
if (!*argv)
//TODO: read from stdin
bb_show_usage();
if (!*argv) {
/* Read from stdin, several numbers per line are accepted */
for (;;) {
char *numstr, *line;
line = xmalloc_fgetline(stdin);
if (!line)
return EXIT_SUCCESS;
numstr = line;
for (;;) {
char *end;
numstr = skip_whitespace(numstr);
if (!numstr[0])
break;
end = skip_non_whitespace(numstr);
if (*end != '\0');
*end++ = '\0';
factorize_numstr(numstr);
numstr = end;
}
free(line);
}
}
do {
wide_t N;
const char *numstr;
/* Coreutils compat */
numstr = skip_whitespace(*argv);
if (*numstr == '+')
numstr++;
N = bb_strtoull(numstr, NULL, 10);
if (errno)
bb_show_usage();
printf("%llu:", N);
factorize(N);
/* Leading spaces are ok (coreutils compat) */
factorize_numstr(skip_whitespace(*argv));
} while (*++argv);
return EXIT_SUCCESS;