Sync upstream FreeBSD (qsort).
This gives us C11 Annex K's qsort_s(), which -- despite being Annex K --
is potentially useful in that it resolves the long-standing argument
about what the signature of qsort_r() is supposed to be. I'll import
it here first, and worry about actually using it separately (given that
glibc/musl and macOS/iOS don't have it; only Windows and [now] FreeBSD,
but not even the other BSDs).
For now, though, this change is a no-op.
Bug: http://b/17203231
Bug: http://b/31807750
Test: treehugger
Change-Id: Id8d2916b608ba8251df8643694da542e9b11eaae
diff --git a/libc/upstream-freebsd/android/include/libc_private.h b/libc/upstream-freebsd/android/include/libc_private.h
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/libc/upstream-freebsd/android/include/libc_private.h
diff --git a/libc/upstream-freebsd/lib/libc/stdlib/qsort.c b/libc/upstream-freebsd/lib/libc/stdlib/qsort.c
index e0db4f3..0d65cd1 100644
--- a/libc/upstream-freebsd/lib/libc/stdlib/qsort.c
+++ b/libc/upstream-freebsd/lib/libc/stdlib/qsort.c
@@ -33,12 +33,20 @@
static char sccsid[] = "@(#)qsort.c 8.1 (Berkeley) 6/4/93";
#endif /* LIBC_SCCS and not lint */
#include <sys/cdefs.h>
-__FBSDID("$FreeBSD: head/lib/libc/stdlib/qsort.c 334928 2018-06-10 17:54:44Z kib $");
+__FBSDID("$FreeBSD$");
+#include <errno.h>
+#include <stdint.h>
#include <stdlib.h>
+#include <string.h>
+#include "libc_private.h"
-#ifdef I_AM_QSORT_R
+#if defined(I_AM_QSORT_R)
+typedef int cmp_t(const void *, const void *, void *);
+#elif defined(I_AM_QSORT_R_COMPAT)
typedef int cmp_t(void *, const void *, const void *);
+#elif defined(I_AM_QSORT_S)
+typedef int cmp_t(const void *, const void *, void *);
#else
typedef int cmp_t(const void *, const void *);
#endif
@@ -65,15 +73,19 @@
#define vecswap(a, b, n) \
if ((n) > 0) swapfunc(a, b, n)
-#ifdef I_AM_QSORT_R
+#if defined(I_AM_QSORT_R)
+#define CMP(t, x, y) (cmp((x), (y), (t)))
+#elif defined(I_AM_QSORT_R_COMPAT)
#define CMP(t, x, y) (cmp((t), (x), (y)))
+#elif defined(I_AM_QSORT_S)
+#define CMP(t, x, y) (cmp((x), (y), (t)))
#else
#define CMP(t, x, y) (cmp((x), (y)))
#endif
static inline char *
med3(char *a, char *b, char *c, cmp_t *cmp, void *thunk
-#ifndef I_AM_QSORT_R
+#if !defined(I_AM_QSORT_R) && !defined(I_AM_QSORT_R_COMPAT) && !defined(I_AM_QSORT_S)
__unused
#endif
)
@@ -83,20 +95,28 @@
:(CMP(thunk, b, c) > 0 ? b : (CMP(thunk, a, c) < 0 ? a : c ));
}
-#ifdef I_AM_QSORT_R
-void
-qsort_r(void *a, size_t n, size_t es, void *thunk, cmp_t *cmp)
-#else
-#define thunk NULL
-void
-qsort(void *a, size_t n, size_t es, cmp_t *cmp)
+/*
+ * The actual qsort() implementation is static to avoid preemptible calls when
+ * recursing. Also give them different names for improved debugging.
+ */
+#if defined(I_AM_QSORT_R)
+#define local_qsort local_qsort_r
+#elif defined(I_AM_QSORT_R_COMPAT)
+#define local_qsort local_qsort_r_compat
+#elif defined(I_AM_QSORT_S)
+#define local_qsort local_qsort_s
#endif
+static void
+local_qsort(void *a, size_t n, size_t es, cmp_t *cmp, void *thunk)
{
char *pa, *pb, *pc, *pd, *pl, *pm, *pn;
size_t d1, d2;
int cmp_result;
int swap_cnt;
+ /* if there are less than 2 elements, then sorting is not needed */
+ if (__predict_false(n < 2))
+ return;
loop:
swap_cnt = 0;
if (n < 7) {
@@ -160,7 +180,12 @@
pn = (char *)a + n * es;
d1 = MIN(pa - (char *)a, pb - pa);
vecswap(a, pb - d1, d1);
- d1 = MIN(pd - pc, pn - pd - es);
+ /*
+ * Cast es to preserve signedness of right-hand side of MIN()
+ * expression, to avoid sign ambiguity in the implied comparison. es
+ * is safely within [0, SSIZE_MAX].
+ */
+ d1 = MIN(pd - pc, pn - pd - (ssize_t)es);
vecswap(pb, pn - d1, d1);
d1 = pb - pa;
@@ -168,11 +193,7 @@
if (d1 <= d2) {
/* Recurse on left partition, then iterate on right partition */
if (d1 > es) {
-#ifdef I_AM_QSORT_R
- qsort_r(a, d1 / es, es, thunk, cmp);
-#else
- qsort(a, d1 / es, es, cmp);
-#endif
+ local_qsort(a, d1 / es, es, cmp, thunk);
}
if (d2 > es) {
/* Iterate rather than recurse to save stack space */
@@ -184,11 +205,7 @@
} else {
/* Recurse on right partition, then iterate on left partition */
if (d2 > es) {
-#ifdef I_AM_QSORT_R
- qsort_r(pn - d2, d2 / es, es, thunk, cmp);
-#else
- qsort(pn - d2, d2 / es, es, cmp);
-#endif
+ local_qsort(pn - d2, d2 / es, es, cmp, thunk);
}
if (d1 > es) {
/* Iterate rather than recurse to save stack space */
@@ -198,3 +215,53 @@
}
}
}
+
+#if defined(I_AM_QSORT_R)
+void
+(qsort_r)(void *a, size_t n, size_t es, cmp_t *cmp, void *thunk)
+{
+ local_qsort_r(a, n, es, cmp, thunk);
+}
+#elif defined(I_AM_QSORT_R_COMPAT)
+void
+__qsort_r_compat(void *a, size_t n, size_t es, void *thunk, cmp_t *cmp)
+{
+ local_qsort_r_compat(a, n, es, cmp, thunk);
+}
+#elif defined(I_AM_QSORT_S)
+errno_t
+qsort_s(void *a, rsize_t n, rsize_t es, cmp_t *cmp, void *thunk)
+{
+ if (n > RSIZE_MAX) {
+ __throw_constraint_handler_s("qsort_s : n > RSIZE_MAX", EINVAL);
+ return (EINVAL);
+ } else if (es > RSIZE_MAX) {
+ __throw_constraint_handler_s("qsort_s : es > RSIZE_MAX",
+ EINVAL);
+ return (EINVAL);
+ } else if (n != 0) {
+ if (a == NULL) {
+ __throw_constraint_handler_s("qsort_s : a == NULL",
+ EINVAL);
+ return (EINVAL);
+ } else if (cmp == NULL) {
+ __throw_constraint_handler_s("qsort_s : cmp == NULL",
+ EINVAL);
+ return (EINVAL);
+ } else if (es <= 0) {
+ __throw_constraint_handler_s("qsort_s : es <= 0",
+ EINVAL);
+ return (EINVAL);
+ }
+ }
+
+ local_qsort_s(a, n, es, cmp, thunk);
+ return (0);
+}
+#else
+void
+qsort(void *a, size_t n, size_t es, cmp_t *cmp)
+{
+ local_qsort(a, n, es, cmp, NULL);
+}
+#endif