libc: Provide ucontext_t/mcontext_t/<sys/ucontext.h>

This patch updates the C library headers to provide ucontext_t
definitions for three architectures.

+ Fix <signal.h> to always define 'struct sigcontext'.

The new declarations are announced with new macros defined in
<sys/cdefs.h> in order to make it easier to adapt client code
that already defines its own, incompatible, versions of the
structures seen here.

http://code.google.com/p/android/issues/detail?id=34784

Change-Id: Ie78c48690a4ce61c50593f6c39639be7fead3596
diff --git a/libc/arch-mips/include/machine/signal.h b/libc/arch-mips/include/machine/signal.h
index 4efb856..6378c61 100644
--- a/libc/arch-mips/include/machine/signal.h
+++ b/libc/arch-mips/include/machine/signal.h
@@ -1,147 +1,58 @@
-/*	$OpenBSD: signal.h,v 1.8 2006/01/09 18:18:37 millert Exp $	*/
-
 /*
- * Copyright (c) 1992, 1993
- *	The Regents of the University of California.  All rights reserved.
- *
- * This code is derived from software contributed to Berkeley by
- * Ralph Campbell.
+ * Copyright (C) 2012 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:
- * 1. Redistributions of source code must retain the above copyright
+ *  * Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
- * 2. 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.
- * 3. Neither the name of the University nor the names of its contributors
- *    may be used to endorse or promote products derived from this software
- *    without specific prior written permission.
+ *  * 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 REGENTS 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 REGENTS 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
+ * 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.
- *
- *	@(#)signal.h	8.1 (Berkeley) 6/10/93
  */
-
-#ifndef _MIPS_SIGNAL_H_
-#define _MIPS_SIGNAL_H_
+#ifndef _ARCH_MIPS_MACHINE_SIGNAL_H_
+#define _ARCH_MIPS_MACHINE_SIGNAL_H_
 
 #include <sys/cdefs.h>
 
-#if !defined(__LANGUAGE_ASSEMBLY)
-#include <sys/types.h>
+__BEGIN_DECLS
 
-/*
- * Machine-dependent signal definitions
- */
-typedef int sig_atomic_t;
+#include <asm/signal.h>
+#include <asm/sigcontext.h>
 
-#if __BSD_VISIBLE || __XPG_VISIBLE >= 420
-
-/*
- * Information pushed on stack when a signal is delivered.
- * This is used by the kernel to restore state following
- * execution of the signal handler.  It is also made available
- * to the handler to allow it to restore state properly if
- * a non-standard exit is performed.
- */
-
-#if defined(__ANDROID__)
-
-/*
- * The Linux and OpenBSD sigcontext structures are slightly different
- * This is the Linux O32 ABI compatible sigcontext
- */
-
-struct sigcontext {
-	unsigned int sc_regmask;
-	unsigned int sc_status;
-	unsigned long long sc_pc;
-	unsigned long long sc_regs[32];
-	unsigned long long sc_fpregs[32];
-	unsigned int sc_acx;
-	unsigned int sc_fpc_csr;
-	unsigned int sc_fpc_eir;
-	unsigned int sc_used_math;
-	unsigned int sc_dsp;
-	unsigned long long sc_mdhi;
-	unsigned long long sc_mdlo;
-	unsigned long sc_hi1;
-	unsigned long sc_lo1;
-	unsigned long sc_hi2;
-	unsigned long sc_lo2;
-	unsigned long sc_hi3;
-	unsigned long sc_lo3;
-};
-
-#else
-
-struct	sigcontext {
-	long	sc_onstack;	/* sigstack state to restore */
-	long	 sc_mask;	/* signal mask to restore */
-	__register_t sc_pc;	/* pc at time of signal */
-	__register_t sc_regs[32]; /* processor regs 0 to 31 */
-	__register_t mullo;	/* mullo and mulhi registers... */
-	__register_t mulhi;	/* mullo and mulhi registers... */
-	f_register_t sc_fpregs[33]; /* fp regs 0 to 31 and csr */
-	long	sc_fpused;	/* fp has been used */
-	long	sc_fpc_eir;	/* floating point exception instruction reg */
-	long	xxx[8];		/* XXX reserved */
-};
+#ifdef _ASM_GENERIC_SIGINFO_H
+#error "You cannot include <asm/siginfo.h> before <signal.h>!"
 #endif
-#endif /* __BSD_VISIBLE || __XPG_VISIBLE >= 420 */
+#define __ARCH_SI_UID_T __kernel_uid32_t
+#include <asm/siginfo.h>
+#undef __ARCH_SI_UID_T
 
-#else /* __LANGUAGE_ASSEMBLY */
+#include <stdint.h>
 
-#ifdef __ANDROID__
+/* See comment in arch-arm/include/machine/signal.h.
+ * The MIPS kernel also uses 128-bit signal masks while defining sigset-t
+ * as a 32-bit type.
+ */
+typedef unsigned long __kernel_sigset_t[4];
 
-#define	SC_REGMASK	(0*REGSZ)
-#define	SC_STATUS	(1*REGSZ)
-#define	SC_PC		(2*REGSZ)
-#define	SC_REGS		(SC_PC+8)
-#define	SC_FPREGS	(SC_REGS+32*8)
-#define	SC_ACX		(SC_FPREGS+32*REGSZ_FP)
-#define	SC_FPC_CSR	(SC_ACX+1*REGSZ)
-#define	SC_FPC_EIR	(SC_ACX+2*REGSZ)
-#define	SC_USED_MATH	(SC_ACX+3*REGSZ)
-#define	SC_DSP		(SC_ACX+4*REGSZ)
-#define	SC_MDHI		(SC_ACX+5*REGSZ)
-#define	SC_MDLO		(SC_MDHI+8)
-#define	SC_HI1		(SC_MDLO+8)
-#define	SC_LO1		(SC_HI1+1*REGSZ)
-#define	SC_HI2		(SC_HI1+2*REGSZ)
-#define	SC_LO2		(SC_HI1+3*REGSZ)
-#define	SC_HI3		(SC_HI1+4*REGSZ)
-#define	SC_LO3		(SC_HI1+5*REGSZ)
-/* OpenBSD compatibility */
-#define	SC_MASK		SC_REGMASK
-#define	SC_FPUSED	SC_USED_MATH
+/* Note: Unlike ARM and x86, the MIPS <asm/signal.h> properly defines _NSIG
+ * and thus SIGRTMAX. */
 
-#else
+__END_DECLS
 
-#define SC_ONSTACK	(0 * REGSZ)
-#define	SC_MASK		(1 * REGSZ)
-#define	SC_PC		(2 * REGSZ)
-#define	SC_REGS		(3 * REGSZ)
-#define	SC_MULLO	(35 * REGSZ)
-#define	SC_MULHI	(36 * REGSZ)
-#define	SC_FPREGS	(37 * REGSZ)
-#define	SC_FPUSED	(70 * REGSZ)
-#define	SC_FPC_EIR	(71 * REGSZ)
-
-#endif /* __ANDROID__ */
-
-#endif /* __LANGUAGE_ASSEMBLY */
-
-#endif	/* !_MIPS_SIGNAL_H_ */
+#endif /* _ARCH_MIPS_MACHINE_SIGNAL_H_ */