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/*
* Copyright (c) 2018, ARM Limited and Contributors. All rights reserved.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
#ifndef SETJMP_H
#define SETJMP_H
#define JMP_CTX_X19 0x0
#define JMP_CTX_X21 0x10
#define JMP_CTX_X23 0x20
#define JMP_CTX_X25 0x30
#define JMP_CTX_X27 0x40
#define JMP_CTX_X29 0x50
#define JMP_CTX_SP 0x60
#define JMP_CTX_END 0x70
#define JMP_SIZE (JMP_CTX_END >> 3)
#ifndef __ASSEMBLY__
#include <stdint.h>
/* Jump buffer hosting x18 - x30 and sp_el0 registers */
struct jmpbuf {
uint64_t buf[JMP_SIZE];
} __aligned(16);
/*
* Set a jump point, and populate the jump buffer with context information so
* that longjmp() can jump later. The caller must adhere to the following
* conditions:
*
* - After calling this function, the stack must not be shrunk. The contents of
* the stack must not be changed either.
*
* - If the caller were to 'return', the buffer must be considered invalid, and
* must not be used with longjmp().
*
* The caller will observe this function returning at two distinct
* circumstances, each with different return values:
*
* - Zero, when the buffer is setup;
*
* - Non-zero, when a call to longjmp() is made (presumably by one of the
* callee functions) with the same jump buffer.
*/
int setjmp(struct jmpbuf *buf);
/*
* Reset execution to a jump point, and restore context information according to
* the jump buffer populated by setjmp().
*/
void longjmp(struct jmpbuf *buf);
#endif /* __ASSEMBLY__ */
#endif /* SETJMP_H */