Implement qsort_s() as a wrapper to the GNU version of qsort_r(1) and
use it on Linux. Performance increases slightly:
Test HEAD^ HEAD
--------------------------------------------------------------------
0071.2: sort(1) 0.10(0.20+0.02) 0.10(0.21+0.01) +0.0%
0071.3: string_list_sort() 0.17(0.15+0.01) 0.16(0.15+0.01) -5.9%
Additionally the unstripped size of compat/qsort_s.o falls from 24576
to 16544 bytes in my build.
IMHO these savings aren't worth the increased complexity of having to
support two implementations.
---
Makefile | 6 ++++++
compat/qsort_s.c | 18 ++++++++++++++++++
config.mak.uname | 1 +
3 files changed, 25 insertions(+)
diff --git a/Makefile b/Makefile
index 53ecc84e28..46db1c773f 100644
--- a/Makefile
+++ b/Makefile
@@ -282,6 +282,9 @@ all::
# Define HAVE_ISO_QSORT_S if your platform provides a qsort_s() that's
# compatible with the one described in C11 Annex K.
#
+# Define HAVE_GNU_QSORT_R if your platform provides a qsort_r() that's
+# compatible with the one introduced with glibc 2.8.
+#
# Define UNRELIABLE_FSTAT if your system's fstat does not return the same
# information on a not yet closed file that lstat would return for the same
# file after it was closed.
@@ -1426,6 +1429,9 @@ ifdef HAVE_ISO_QSORT_S
else
COMPAT_OBJS += compat/qsort_s.o
endif
+ifdef HAVE_GNU_QSORT_R
+ COMPAT_CFLAGS += -DHAVE_GNU_QSORT_R
+endif
ifdef RUNTIME_PREFIX
COMPAT_CFLAGS += -DRUNTIME_PREFIX
endif
diff --git a/compat/qsort_s.c b/compat/qsort_s.c
index 52d1f0a73d..763ee1faae 100644
--- a/compat/qsort_s.c
+++ b/compat/qsort_s.c
@@ -1,5 +1,21 @@
#include "../git-compat-util.h"
+#if defined HAVE_GNU_QSORT_R
+
+int git_qsort_s(void *b, size_t n, size_t s,
+ int (*cmp)(const void *, const void *, void *), void *ctx)
+{
+ if (!n)
+ return 0;
+ if (!b || !cmp)
+ return -1;
+
+ qsort_r(b, n, s, cmp, ctx);
+ return 0;
+}
+
+#else
+
/*
* A merge sort implementation, simplified from the qsort implementation
* by Mike Haertel, which is a part of the GNU C Library.
@@ -67,3 +83,5 @@ int git_qsort_s(void *b, size_t n, size_t s,
}
return 0;
}
+
+#endif
diff --git a/config.mak.uname b/config.mak.uname
index 447f36ac2e..a1858f54ff 100644
--- a/config.mak.uname
+++ b/config.mak.uname
@@ -37,6 +37,7 @@ ifeq ($(uname_S),Linux)
NEEDS_LIBRT = YesPlease
HAVE_GETDELIM = YesPlease
SANE_TEXT_GREP=-a
+ HAVE_GNU_QSORT_R = YesPlease
endif
ifeq ($(uname_S),GNU/kFreeBSD)
HAVE_ALLOCA_H = YesPlease
--
2.11.0