ucontext_t support for Android x86.

sandbox/linux/services/android_x86_ucontext.h

+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef SANDBOX_LINUX_SERVICES_ANDROID_X86_UCONTEXT_H_
+#define SANDBOX_LINUX_SERVICES_ANDROID_X86_UCONTEXT_H_
+
+#include <asm/sigcontext.h>
+#include <signal.h>
+
+#if !defined(__BIONIC_HAVE_UCONTEXT_T)

[jln (very slow on Chromium), 2013/01/08 22:26:09]

That's lovely! Do you mind patching it on the arm version as well ?

Even better: have it in a global android_ucontext.h that includes the other
files.

+/* Old versions of the Android <signal.h> didn't define ucontext_t. */
+
+/* Type for general register. */
+typedef int greg_t;
+
+/* asm/sigcontext.h has same structure definition based on Linux kernel header.
+ * But it's not compatible with glibc definition (no gregs).
+ */
+typedef struct {
+  greg_t    gregs[19];
+  void*     fpregs;
+  unsigned long int oldmask;
+  unsigned long int cr2;
+} mcontext_t;
+
+enum {
+  REG_GS = 0, REG_FS, REG_ES, REG_DS,
+  REG_EDI, REG_ESI, REG_EBP, REG_ESP,
+  REG_EBX, REG_EDX, REG_ECX, REG_EAX,
+  REG_TRAPNO, REG_ERR, REG_EIP, REG_CS,
+  REG_EFL, REG_UESP, REG_SS
+};
+
+/* Machine context at the time a signal was raised. */
+typedef struct ucontext {
+  unsigned long int uc_flags;
+  struct ucontext* uc_link;
+  stack_t uc_stack;
+  mcontext_t uc_mcontext;
+  sigset_t uc_sigmask;
+} ucontext_t;

[digit1, 2013/01/09 09:47:18]

that looks good to me too :)

+#endif /* !__BIONIC_HAVE_UCONTEXT_T */
+
+#endif  // SANDBOX_LINUX_SERVICES_ANDROID_ARM_UCONTEXT_H_