Alter the prototype of qsort_r(3) to match POSIX, which adopted the

glibc-based interface.

Unfortunately, the glibc maintainers, despite knowing the existence
of the FreeBSD qsort_r(3) interface in 2004 and refused to add the
same interface to glibc based on grounds of the lack of standardization
and portability concerns, has decided it was a good idea to introduce
their own qsort_r(3) interface in 2007 as a GNU extension with a
slightly different and incompatible interface.

With the adoption of their interface as POSIX standard, let's switch
to the same prototype, there is no need to remain incompatible.

C++ and C applications written for the historical FreeBSD interface
get source level compatibility when building in C++ mode, or when
building with a C compiler with C11 generics support, provided that
the caller passes a fifth parameter of qsort_r() that exactly matches
the historical FreeBSD comparator function pointer type and does not
redefine the historical qsort_r(3) prototype in their source code.

Symbol versioning is used to keep old binaries working.

MFC:			never
Relnotes:		yes
Reviewed by:		cem, imp, hps, pauamma
Differential revision:	https://reviews.freebsd.org/D17083

1 files changed, 4 insertions, 5 deletions

diff --git a/sys/dev/bhnd/nvram/bhnd_nvram_store_subr.c b/sys/dev/bhnd/nvram/bhnd_nvram_store_subr.c
index 730b9d51da45..fd05648147f5 100644
--- a/sys/dev/bhnd/nvram/bhnd_nvram_store_subr.c
+++ b/sys/dev/bhnd/nvram/bhnd_nvram_store_subr.c
@@ -59,8 +59,7 @@ __FBSDID("$FreeBSD$");
 
 #include "bhnd_nvram_storevar.h"
 
-static int			 bhnd_nvstore_idx_cmp(void *ctx,
-				     const void *lhs, const void *rhs);
+static int bhnd_nvstore_idx_cmp(const void *lhs, const void *rhs, void *ctx);
 
 /**
  * Allocate and initialize a new path instance.
@@ -198,7 +197,7 @@ bhnd_nvstore_index_append(struct bhnd_nvram_store *sc,
 
 /* sort function for bhnd_nvstore_index_prepare() */
 static int
-bhnd_nvstore_idx_cmp(void *ctx, const void *lhs, const void *rhs)
+bhnd_nvstore_idx_cmp(const void *lhs, const void *rhs, void *ctx)
 {
 	struct bhnd_nvram_store	*sc;
 	void			*l_cookiep, *r_cookiep;
@@ -259,8 +258,8 @@ bhnd_nvstore_index_prepare(struct bhnd_nvram_store *sc,
 	BHND_NVSTORE_LOCK_ASSERT(sc, MA_OWNED);
 
 	/* Sort the index table */
-	qsort_r(index->cookiep, index->count, sizeof(index->cookiep[0]), sc,
-	    bhnd_nvstore_idx_cmp);
+	qsort_r(index->cookiep, index->count, sizeof(index->cookiep[0]),
+	    bhnd_nvstore_idx_cmp, sc);
 
 	return (0);
 }