From: Denys Vlasenko <vda.linux@googlemail.com>
Date: Mon, 8 Jul 2013 00:39:51 +0000 (+0200)
Subject: tail: code shrink
X-Git-Tag: 1_22_0~155
X-Git-Url: https://git.librecmc.org/?a=commitdiff_plain;h=d87fcd48886f26373ca12bcfcff9cea44ce9fae4;p=oweals%2Fbusybox.git
tail: code shrink
function old new delta
tail_main 1548 1613 +65
tail_read 136 34 -102
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 1/1 up/down: 65/-102) Total: -37 bytes
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
---
diff --git a/coreutils/tail.c b/coreutils/tail.c
index fb07ca27b..c9f9d00f6 100644
--- a/coreutils/tail.c
+++ b/coreutils/tail.c
@@ -66,23 +66,10 @@ static void tail_xprint_header(const char *fmt, const char *filename)
bb_perror_nomsg_and_die();
}
-static ssize_t tail_read(int fd, char *buf, size_t count, int follow)
+static ssize_t tail_read(int fd, char *buf, size_t count)
{
ssize_t r;
- if (follow) {
- /* tail -f keeps following files even if they are truncated */
- off_t current;
- struct stat sbuf;
-
- /* /proc files report zero st_size, don't lseek them */
- if (fstat(fd, &sbuf) == 0 && sbuf.st_size > 0) {
- current = lseek(fd, 0, SEEK_CUR);
- if (sbuf.st_size < current)
- xlseek(fd, 0, SEEK_SET);
- }
- }
-
r = full_read(fd, buf, count);
if (r < 0) {
bb_perror_msg(bb_msg_read_error);
@@ -255,7 +242,7 @@ int tail_main(int argc, char **argv)
* Used only by +N code ("start from Nth", 1-based): */
seen = 1;
newlines_seen = 0;
- while ((nread = tail_read(fd, buf, tailbufsize - taillen, /*follow:*/ 0)) > 0) {
+ while ((nread = tail_read(fd, buf, tailbufsize - taillen)) > 0) {
if (G.from_top) {
int nwrite = nread;
if (seen < count) {
@@ -367,7 +354,19 @@ int tail_main(int argc, char **argv)
if (nfiles > header_threshhold) {
fmt = header_fmt_str;
}
- while ((nread = tail_read(fd, tailbuf, BUFSIZ, /*follow:*/ 1)) > 0) {
+ for (;;) {
+ /* tail -f keeps following files even if they are truncated */
+ struct stat sbuf;
+ /* /proc files report zero st_size, don't lseek them */
+ if (fstat(fd, &sbuf) == 0 && sbuf.st_size > 0) {
+ off_t current = lseek(fd, 0, SEEK_CUR);
+ if (sbuf.st_size < current)
+ xlseek(fd, 0, SEEK_SET);
+ }
+
+ nread = tail_read(fd, tailbuf, BUFSIZ);
+ if (nread <= 0)
+ break;
if (fmt) {
tail_xprint_header(fmt, filename);
fmt = NULL;