Put back inline definitions if using an old API.

All these inlines were turned in to out of line definitions in L.
This brings us a step closer to being able to just use the current
bionic headers for the NDK, rather than having many old versions of
them.

Change-Id: Ie010bc727d78d3742abc577c70f6578db2e68625

libc/include/android/legacy_signal_inlines.h

@@ -0,0 +1,98 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *  * Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  * 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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
+ * COPYRIGHT OWNER 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.
+ */
+
+#ifndef _ANDROID_LEGACY_SIGNAL_INLINES_H_
+#define _ANDROID_LEGACY_SIGNAL_INLINES_H_
+
+#include <string.h>
+#include <sys/cdefs.h>
+
+__BEGIN_DECLS
+
+extern sighandler_t bsd_signal(int signum, sighandler_t handler);
+
+static __inline int sigismember(sigset_t *set, int signum) {
+  /* Signal numbers start at 1, but bit positions start at 0. */
+  int bit = signum - 1;
+  const unsigned long *local_set = (const unsigned long *)set;
+  if (set == NULL || bit < 0 || bit >= (int)(8 * sizeof(sigset_t))) {
+    errno = EINVAL;
+    return -1;
+  }
+  return (int)((local_set[bit / LONG_BIT] >> (bit % LONG_BIT)) & 1);
+}
+
+static __inline int sigaddset(sigset_t *set, int signum) {
+  /* Signal numbers start at 1, but bit positions start at 0. */
+  int bit = signum - 1;
+  unsigned long *local_set = (unsigned long *)set;
+  if (set == NULL || bit < 0 || bit >= (int)(8 * sizeof(sigset_t))) {
+    errno = EINVAL;
+    return -1;
+  }
+  local_set[bit / LONG_BIT] |= 1UL << (bit % LONG_BIT);
+  return 0;
+}
+
+static __inline int sigdelset(sigset_t *set, int signum) {
+  /* Signal numbers start at 1, but bit positions start at 0. */
+  int bit = signum - 1;
+  unsigned long *local_set = (unsigned long *)set;
+  if (set == NULL || bit < 0 || bit >= (int)(8 * sizeof(sigset_t))) {
+    errno = EINVAL;
+    return -1;
+  }
+  local_set[bit / LONG_BIT] &= ~(1UL << (bit % LONG_BIT));
+  return 0;
+}
+
+static __inline int sigemptyset(sigset_t *set) {
+  if (set == NULL) {
+    errno = EINVAL;
+    return -1;
+  }
+  memset(set, 0, sizeof(sigset_t));
+  return 0;
+}
+
+static __inline int sigfillset(sigset_t *set) {
+  if (set == NULL) {
+    errno = EINVAL;
+    return -1;
+  }
+  memset(set, ~0, sizeof(sigset_t));
+  return 0;
+}
+
+static __inline sighandler_t signal(int s, sighandler_t f) {
+  return bsd_signal(s, f);
+}
+
+__END_DECLS
+
+#endif /* _ANDROID_LEGACY_SIGNAL_INLINES_H_ */