ls: add support for -H

[oweals/busybox.git] / coreutils / tail.c

diff --git a/coreutils/tail.c b/coreutils/tail.c
index 0be16631509aef0ded97004e9ee64bb3ab526a63..df881a37a19263c94b59800a6a856e7c5766672f 100644 (file)
--- a/coreutils/tail.c
+++ b/coreutils/tail.c
@@ -4,7 +4,7 @@
  *
  * Copyright (C) 2001 by Matt Kraai <kraai@alumni.carnegiemellon.edu>
  *
- * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
+ * Licensed under GPLv2 or later, see file LICENSE in this source tree.
  */
 
 /* BB_AUDIT SUSv3 compliant (need fancy for -c) */
@@ -35,7 +35,7 @@ static const struct suffix_mult tail_suffixes[] = {
 
 struct globals {
        bool status;
-};
+} FIX_ALIASING;
 #define G (*(struct globals*)&bb_common_bufsiz1)
 
 static void tail_xprint_header(const char *fmt, const char *filename)
@@ -66,7 +66,7 @@ static ssize_t tail_read(int fd, char *buf, size_t count)
        return r;
 }
 
-static const char header_fmt[] ALIGN1 = "\n==> %s <==\n";
+#define header_fmt_str "\n==> %s <==\n"
 
 static unsigned eat_num(const char *p)
 {
@@ -166,7 +166,7 @@ int tail_main(int argc, char **argv)
        tailbuf = xmalloc(tailbufsize);
 
        /* tail the files */
-       fmt = header_fmt + 1; /* skip header leading newline on first output */
+       fmt = header_fmt_str + 1; /* skip header leading newline on first output */
        i = 0;
        do {
                char *buf;
@@ -181,7 +181,7 @@ int tail_main(int argc, char **argv)
 
                if (nfiles > header_threshhold) {
                        tail_xprint_header(fmt, argv[i]);
-                       fmt = header_fmt;
+                       fmt = header_fmt_str;
                }
 
                if (!from_top) {
@@ -241,7 +241,8 @@ int tail_main(int argc, char **argv)
                                                } while (nwrite);
                                        }
                                }
-                               xwrite(STDOUT_FILENO, buf + nread - nwrite, nwrite);
+                               if (nwrite > 0)
+                                       xwrite(STDOUT_FILENO, buf + nread - nwrite, nwrite);
                        } else if (count) {
                                if (COUNT_BYTES) {
                                        taillen += nread;
@@ -332,7 +333,7 @@ int tail_main(int argc, char **argv)
                        if (ENABLE_FEATURE_FANCY_TAIL && fd < 0)
                                continue;
                        if (nfiles > header_threshhold) {
-                               fmt = header_fmt;
+                               fmt = header_fmt_str;
                        }
                        while ((nread = tail_read(fd, tailbuf, BUFSIZ)) > 0) {
                                if (fmt) {
@@ -345,6 +346,7 @@ int tail_main(int argc, char **argv)
        }
        if (ENABLE_FEATURE_CLEAN_UP) {
                free(fds);
+               free(tailbuf);
        }
        return G.status;
 }