Files
asterinas/test/apps/mmap/mmap_and_mremap.c
2025-06-21 16:18:09 +08:00

81 lines
2.1 KiB
C

// SPDX-License-Identifier: MPL-2.0
#define _GNU_SOURCE
#include <stdio.h>
#include <stdlib.h>
#include <sys/mman.h>
#include <unistd.h>
#include <string.h>
#include <errno.h>
#include "../network/test.h"
#define PAGE_SIZE 4096
const char *content = "kjfkljk*wigo&h";
void *x_mmap(void *addr, size_t length, int prot, int flags, int fd,
off_t offset)
{
void *result = mmap(addr, length, prot, flags, fd, offset);
if (result == MAP_FAILED) {
perror("mmap");
exit(EXIT_FAILURE);
}
return result;
}
FN_TEST(mmap_and_mremap)
{
char *addr = x_mmap(NULL, 3 * PAGE_SIZE, PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
TEST_SUCC(munmap(addr, 3 * PAGE_SIZE));
addr = x_mmap(addr, PAGE_SIZE, PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS | MAP_FIXED, -1, 0);
strcpy(addr, content);
char *addr2 = x_mmap(addr + 2 * PAGE_SIZE, PAGE_SIZE,
PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS | MAP_FIXED, -1, 0);
char *new_addr = mremap(addr, PAGE_SIZE, 3 * PAGE_SIZE, MREMAP_MAYMOVE);
if (new_addr == MAP_FAILED) {
perror("mremap");
exit(EXIT_FAILURE);
}
// The following operation (if uncommented) would cause a segmentation fault.
// strcpy(addr, "Writing to old address");
TEST_RES(strcmp(new_addr, content), _ret == 0);
strcpy(new_addr + PAGE_SIZE, "Writing to page 2 (new)");
strcpy(new_addr + 2 * PAGE_SIZE, "Writing to page 3 (new)");
TEST_SUCC(munmap(new_addr, 3 * PAGE_SIZE));
TEST_SUCC(munmap(addr2, PAGE_SIZE));
}
END_TEST()
FN_TEST(mmap_and_mremap_fixed)
{
char *addr = x_mmap(NULL, PAGE_SIZE, PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
strcpy(addr, content);
// Map and unmap a target region to ensure we know it's free
char *fixed_addr = x_mmap(NULL, PAGE_SIZE, PROT_NONE,
MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
TEST_SUCC(munmap(fixed_addr, PAGE_SIZE)); // free it for mremap
char *new_addr = mremap(addr, PAGE_SIZE, PAGE_SIZE,
MREMAP_MAYMOVE | MREMAP_FIXED, fixed_addr);
if (new_addr != fixed_addr) {
perror("mremap");
exit(EXIT_FAILURE);
}
TEST_RES(strcmp(new_addr, content), _ret == 0);
TEST_SUCC(munmap(new_addr, PAGE_SIZE));
}
END_TEST()