path: root/src/stdlib/qsort_nr.c
diff options
author√Črico Nogueira <>2021-03-09 18:02:13 -0300
committerRich Felker <>2021-09-23 20:09:22 -0400
commitb76f37fd5625d038141b52184956fb4b7838e9a5 (patch)
tree8375a3587dcf9c921cedb4858f4c6d2400f909cd /src/stdlib/qsort_nr.c
parent7be59733d71ada3a32a98622507399253f1d5e48 (diff)
add qsort_r and make qsort a wrapper around it
we make qsort a wrapper by providing a wrapper_cmp function that uses the extra argument as a function pointer. should be optimized to a tail call on most architectures, as long as it's built with -fomit-frame-pointer, so the performance impact should be minimal. to keep the git history clean, for now qsort_r is implemented in qsort.c and qsort is implemented in qsort_nr.c. qsort.c also received a few trivial cleanups, including replacing (*cmp)() calls with cmp(). qsort_nr.c contains only wrapper_cmp and qsort as a qsort_r wrapper itself.
Diffstat (limited to 'src/stdlib/qsort_nr.c')
1 files changed, 14 insertions, 0 deletions
diff --git a/src/stdlib/qsort_nr.c b/src/stdlib/qsort_nr.c
new file mode 100644
index 00000000..efe7ccec
--- /dev/null
+++ b/src/stdlib/qsort_nr.c
@@ -0,0 +1,14 @@
+#define _BSD_SOURCE
+#include <stdlib.h>
+typedef int (*cmpfun)(const void *, const void *);
+static int wrapper_cmp(const void *v1, const void *v2, void *cmp)
+ return ((cmpfun)cmp)(v1, v2);
+void qsort(void *base, size_t nel, size_t width, cmpfun cmp)
+ __qsort_r(base, nel, width, wrapper_cmp, cmp);