libc: Fix alphasort() signature (and implementation).

The declaration for alphasort() in <dirent.h> used the deprecated:

  int alphasort(const void*, const void*);

while both Posix and GLibc use instead:

  int alphasort(const struct dirent** a, const struct dirent** b);

See: http://pubs.opengroup.org/onlinepubs/9699919799/functions/alphasort.html

This patch does the following:

- Update the declaration to match Posix/GLibc
- Get rid of the upstream BSD code which isn't compatible with the new
  signature.
- Implement a new trivial alphasort() with the right signature, and
  ensure that it uses strcoll() instead of strcmp().
- Remove Bionic-specific #ifdef .. #else .. #endif block in
  dirent_test.cpp which uses alphasort().

Even through strcoll() currently uses strcmp(), this does the right
thing in the case where we decide to update strcoll() to properly
implement locale-specific ordered comparison.

Change-Id: I4fd45604d8a940aaf2eb0ecd7d73e2f11c9bca96

4 files changed, 6 insertions, 62 deletions

diff --git a/libc/Android.mk b/libc/Android.mk
index b0220c187..bb3fd00f3 100644
--- a/libc/Android.mk
+++ b/libc/Android.mk
@@ -279,13 +279,13 @@ libc_common_src_files := \
 
 libc_bionic_src_files := \
     bionic/assert.cpp \
+    bionic/dirent.cpp \
     bionic/eventfd.cpp \
     bionic/__fgets_chk.cpp \
     bionic/getcwd.cpp \
     bionic/__memcpy_chk.cpp \
     bionic/__memmove_chk.cpp \
     bionic/__memset_chk.cpp \
-    bionic/opendir.cpp \
     bionic/setlocale.cpp \
     bionic/__strcat_chk.cpp \
     bionic/__strcpy_chk.cpp \
@@ -309,7 +309,6 @@ libc_upstream_netbsd_src_files := \
     upstream-netbsd/common/lib/libc/hash/sha1/sha1.c \
     upstream-netbsd/common/lib/libc/inet/inet_addr.c \
     upstream-netbsd/libc/compat-43/creat.c \
-    upstream-netbsd/libc/gen/alphasort.c \
     upstream-netbsd/libc/gen/ftw.c \
     upstream-netbsd/libc/gen/nftw.c \
     upstream-netbsd/libc/gen/nice.c \
diff --git a/libc/bionic/opendir.cpp b/libc/bionic/dirent.cpp
index cd5b2211c..3a7b5b414 100644
--- a/libc/bionic/opendir.cpp
+++ b/libc/bionic/dirent.cpp
@@ -190,3 +190,7 @@ int scandir(const char* path, dirent*** namelist,
   *namelist = de_list;
   return n_elem;
 }
+
+int alphasort(const struct dirent** a, const struct dirent** b) {
+  return strcoll((*a)->d_name, (*b)->d_name);
+}
diff --git a/libc/include/dirent.h b/libc/include/dirent.h
index 78c3a5a7e..3bd7a0fae 100644
--- a/libc/include/dirent.h
+++ b/libc/include/dirent.h
@@ -62,7 +62,7 @@ extern  int              readdir_r(DIR*  dirp, struct dirent* entry, struct dire
 extern  int              closedir(DIR* dirp);
 extern  void             rewinddir(DIR* dirp);
 extern  int              dirfd(DIR* dirp);
-extern  int              alphasort(const void* a, const void* b);
+extern  int              alphasort(const struct dirent** a, const struct dirent** b);
 extern  int              scandir(const char* dir, struct dirent*** namelist,
                                  int(*filter)(const struct dirent*),
                                  int(*compar)(const struct dirent**,
diff --git a/libc/upstream-netbsd/libc/gen/alphasort.c b/libc/upstream-netbsd/libc/gen/alphasort.c
deleted file mode 100644
index c8310d425..000000000
--- a/libc/upstream-netbsd/libc/gen/alphasort.c
+++ /dev/null
@@ -1,59 +0,0 @@
-/*	$NetBSD: alphasort.c,v 1.2 2009/03/01 19:59:55 christos Exp $	*/
-
-/*
- * Copyright (c) 1983, 1993
- *	The Regents of the University of California.  All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- *    notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- *    notice, this list of conditions and the following disclaimer in the
- *    documentation and/or other materials provided with the distribution.
- * 3. Neither the name of the University nor the names of its contributors
- *    may be used to endorse or promote products derived from this software
- *    without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
- * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
- * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
- * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
- * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
- * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
- * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
- * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
- * SUCH DAMAGE.
- */
-
-#include <sys/cdefs.h>
-#if defined(LIBC_SCCS) && !defined(lint)
-#if 0
-static char sccsid[] = "@(#)scandir.c	8.3 (Berkeley) 1/2/94";
-#else
-__RCSID("$NetBSD: alphasort.c,v 1.2 2009/03/01 19:59:55 christos Exp $");
-#endif
-#endif /* LIBC_SCCS and not lint */
-
-#include "namespace.h"
-
-#include <assert.h>
-#include <dirent.h>
-#include <string.h>
-
-/*
- * Alphabetic order comparison routine for those who want it.
- */
-int
-alphasort(const void *d1, const void *d2)
-{
-
-	_DIAGASSERT(d1 != NULL);
-	_DIAGASSERT(d2 != NULL);
-
-	return (strcmp((*(const struct dirent *const *)d1)->d_name,
-	    (*(const struct dirent *const *)d2)->d_name));
-}