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/*
* linux-user semihosting checks
*
* Copyright (c) 2019
* Written by Alex Bennée <alex.bennee@linaro.org>
*
* SPDX-License-Identifier: GPL-3.0-or-later
*/
#define SYS_WRITE0 0x04
#define SYS_HEAPINFO 0x16
#define SYS_REPORTEXC 0x18
#include <stdint.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include "semicall.h"
int main(int argc, char *argv[argc])
{
#if UINTPTR_MAX == UINT32_MAX
uintptr_t exit_code = 0x20026;
#else
uintptr_t exit_block[2] = {0x20026, 0};
uintptr_t exit_code = (uintptr_t) &exit_block;
#endif
struct {
void *heap_base;
void *heap_limit;
void *stack_base;
void *stack_limit;
} info;
void *ptr_to_info = (void *) &info;
__semi_call(SYS_WRITE0, (uintptr_t) "Checking HeapInfo\n");
memset(&info, 0, sizeof(info));
__semi_call(SYS_HEAPINFO, (uintptr_t) &ptr_to_info);
if (info.heap_base == NULL || info.heap_limit == NULL) {
printf("null heap: %p -> %p\n", info.heap_base, info.heap_limit);
exit(1);
}
/* Error if heap base is above limit */
if ((uintptr_t) info.heap_base >= (uintptr_t) info.heap_limit) {
printf("heap base %p >= heap_limit %p\n",
info.heap_base, info.heap_limit);
exit(2);
}
if (info.stack_base == NULL || info.stack_limit) {
printf("null stack: %p -> %p\n", info.stack_base, info.stack_limit);
exit(3);
}
/* check our local variables are indeed inside the reported stack */
if (ptr_to_info > info.stack_base) {
printf("info appears to be above stack: %p > %p\n", ptr_to_info,
info.stack_base);
exit(4);
} else if (ptr_to_info < info.stack_limit) {
printf("info appears to be outside stack: %p < %p\n", ptr_to_info,
info.stack_limit);
exit(5);
}
if (ptr_to_info > info.heap_base && ptr_to_info < info.heap_limit) {
printf("info appears to be inside the heap: %p in %p:%p\n",
ptr_to_info, info.heap_base, info.heap_limit);
exit(6);
}
printf("heap: %p -> %p\n", info.heap_base, info.heap_limit);
printf("stack: %p -> %p\n", info.stack_base, info.stack_limit);
__semi_call(SYS_WRITE0, (uintptr_t) "Passed HeapInfo checks");
__semi_call(SYS_REPORTEXC, exit_code);
/* if we get here we failed */
return -1;
}
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