libbb: use full_write1_str() to shrink busybox_main()

There are two calls to dup2() in busybox_main().  These were
introduced to coerce full_write2_str() into writing to stdout.

The relevant commits were: 21278dff7 (busybox: do not print help
to fd 2, print it to fd 1) and 5a7c72015 (busybox --list option.
+140 bytes. Rob wanted it.)

Later, in commit 729ecb87b (bbconfig: make it independent from
printf functions), the function full_write1_str() was added.

Using this in busybox_main() allows us to drop the dup2() calls.

function                                             old     new   delta
run_applet_and_exit                                  796     760     -36
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-36)             Total: -36 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

1 files changed, 11 insertions, 13 deletions

diff --git a/libbb/appletlib.c b/libbb/appletlib.c
index d9cc48423..ad373ae1c 100644
--- a/libbb/appletlib.c
+++ b/libbb/appletlib.c
@@ -776,10 +776,9 @@ int busybox_main(int argc UNUSED_PARAM, char **argv)
  help:
                 output_width = get_terminal_width(2);
 
-                dup2(1, 2);
-                full_write2_str(bb_banner); /* reuse const string */
-                full_write2_str(" multi-call binary.\n"); /* reuse */
-                full_write2_str(
+                full_write1_str(bb_banner); /* reuse const string */
+                full_write1_str(" multi-call binary.\n"); /* reuse */
+                full_write1_str(
                         "BusyBox is copyrighted by many authors between 1998-2015.\n"
                         "Licensed under GPLv2. See source distribution for detailed\n"
                         "copyright notices.\n"
@@ -817,20 +816,20 @@ int busybox_main(int argc UNUSED_PARAM, char **argv)
                 while (*a) {
                         int len2 = strlen(a) + 2;
                         if (col >= (int)output_width - len2) {
-                                full_write2_str(",\n");
+                                full_write1_str(",\n");
                                 col = 0;
                         }
                         if (col == 0) {
                                 col = 6;
-                                full_write2_str("\t");
+                                full_write1_str("\t");
                         } else {
-                                full_write2_str(", ");
+                                full_write1_str(", ");
                         }
-                        full_write2_str(a);
+                        full_write1_str(a);
                         col += len2;
                         a += len2 - 1;
                 }
-                full_write2_str("\n");
+                full_write1_str("\n");
                 return 0;
         }
 
@@ -850,14 +849,13 @@ int busybox_main(int argc UNUSED_PARAM, char **argv)
         if (is_prefixed_with(argv[1], "--list")) {
                 unsigned i = 0;
                 const char *a = applet_names;
-                dup2(1, 2);
                 while (*a) {
 #  if ENABLE_FEATURE_INSTALLER
                         if (argv[1][6]) /* --list-full? */
-                                full_write2_str(install_dir[APPLET_INSTALL_LOC(i)] + 1);
+                                full_write1_str(install_dir[APPLET_INSTALL_LOC(i)] + 1);
 #  endif
-                        full_write2_str(a);
-                        full_write2_str("\n");
+                        full_write1_str(a);
+                        full_write1_str("\n");
                         i++;
                         while (*a++ != '\0')
                                 continue;