ericonr
/
util-linux
mirror of https://github.com/ericonr/util-linux.git
1
0
Fork 0
Code Issues Projects Releases Wiki Activity

rev: use string printing rather than character output 

Fliping a string in memory, and printing it with multibyte output
function makes the command about 1/3 quicker.

Signed-off-by: Sami Kerola <kerolasa@iki.fi>
This commit is contained in:
Sami Kerola 2013-07-28 22:11:21 +01:00 committed by Karel Zak
parent c8498f2fad
commit 4b4eb34004
1 changed files with 13 additions and 8 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

21
text-utils/rev.c
View File

@ -86,10 +86,20 @@ static void __attribute__ ((__noreturn__)) usage(FILE * out)
exit(out == stderr ? EXIT_FAILURE : EXIT_SUCCESS);
}
static void reverse_str(wchar_t *str, size_t n)
{
size_t i;
for (i = 0; i < n / 2; ++i) {
wchar_t tmp = str[i];
str[i] = str[n - 1 - i];
str[n - 1 - i] = tmp;
}
}
int main(int argc, char *argv[])
{
char *filename = "stdin";
wchar_t *t;
size_t len, bufsiz = BUFSIZ;
FILE *fp = stdin;
int ch, rval = EXIT_SUCCESS;
@ -153,13 +163,8 @@ int main(int argc, char *argv[])
len = wcslen(buf);
}
if (*(t = buf + len - 1) == '\n')
--t;
for ( ; buf <= t; --t)
putwchar(*t);
if (!feof(fp))
putwchar('\n');
reverse_str(buf, len - 1);
fputws(buf, stdout);
}
if (ferror(fp)) {
warn("%s", filename);