/*
 *  arm signal functions
 *
 *  Copyright (c) 2013 Stacey D. Son
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, see <http://www.gnu.org/licenses/>.
 */

#include "qemu.h"

/*
 * Compare to arm/arm/machdep.c sendsig()
 * Assumes that target stack frame memory is locked.
 */
abi_long set_sigtramp_args(CPUARMState *env, int sig,
                           struct target_sigframe *frame,
                           abi_ulong frame_addr,
                           struct target_sigaction *ka)
{
    /*
     * Arguments to signal handler:
     *  r0 = signal number
     *  r1 = siginfo pointer
     *  r2 = ucontext pointer
     *  r5 = ucontext pointer
     *  pc = signal handler pointer
     *  sp = sigframe struct pointer
     *  lr = sigtramp at base of user stack
     */

    env->regs[0] = sig;
    env->regs[1] = frame_addr +
        offsetof(struct target_sigframe, sf_si);
    env->regs[2] = frame_addr +
        offsetof(struct target_sigframe, sf_uc);

    /* the trampoline uses r5 as the uc address */
    env->regs[5] = frame_addr +
        offsetof(struct target_sigframe, sf_uc);
    env->regs[TARGET_REG_PC] = ka->_sa_handler & ~1;
    env->regs[TARGET_REG_SP] = frame_addr;
    env->regs[TARGET_REG_LR] = TARGET_PS_STRINGS - TARGET_SZSIGCODE;
    /*
     * Low bit indicates whether or not we're entering thumb mode.
     */
    cpsr_write(env, (ka->_sa_handler & 1) * CPSR_T, CPSR_T, CPSRWriteByInstr);

    return 0;
}