diff options
| -rw-r--r-- | coreutils/tail.c | 21 |
1 files changed, 14 insertions, 7 deletions
diff --git a/coreutils/tail.c b/coreutils/tail.c index 74e1423..8a11234 100644 --- a/coreutils/tail.c +++ b/coreutils/tail.c @@ -47,13 +47,16 @@ static void tail_xprint_header(const char *fmt, const char *filename) static ssize_t tail_read(int fd, char *buf, size_t count) { ssize_t r; - off_t current, end; + off_t current; struct stat sbuf; - end = current = lseek(fd, 0, SEEK_CUR); - if (!fstat(fd, &sbuf)) - end = sbuf.st_size; - lseek(fd, end < current ? 0 : current, SEEK_SET); + /* (A good comment is missing here) */ + current = lseek(fd, 0, SEEK_CUR); + /* /proc files report zero st_size, don't lseek them. */ + if (fstat(fd, &sbuf) == 0 && sbuf.st_size) + if (sbuf.st_size < current) + lseek(fd, 0, SEEK_SET); + r = safe_read(fd, buf, count); if (r < 0) { bb_perror_msg(bb_msg_read_error); @@ -67,8 +70,12 @@ static const char header_fmt[] ALIGN1 = "\n==> %s <==\n"; static unsigned eat_num(const char *p) { - if (*p == '-') p++; - else if (*p == '+') { p++; G.status = EXIT_FAILURE; } + if (*p == '-') + p++; + else if (*p == '+') { + p++; + G.status = EXIT_FAILURE; + } return xatou_sfx(p, tail_suffixes); } |