1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
|
/*
* Copyright 2021 The Emscripten Authors. All rights reserved.
* Emscripten is available under two separate licenses, the MIT license and the
* University of Illinois/NCSA Open Source License. Both these licenses can be
* found in the LICENSE file.
*/
#include <assert.h>
#include <emscripten/emscripten.h>
#include <emscripten/wasmfs.h>
#include <errno.h>
#include <fcntl.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#include <unistd.h>
void write_and_read(const char* msg, int fd, const char* expected) {
char buf[200] = {};
errno = 0;
write(fd, msg, strlen(msg));
assert(errno == 0);
errno = 0;
lseek(fd, 0, SEEK_SET);
assert(errno == 0);
read(fd, buf, sizeof(buf));
assert(errno == 0);
printf("%s\n", buf);
assert(strcmp(buf, expected) == 0);
}
static backend_t make_js_file_backend(void* arg) {
return wasmfs_create_js_file_backend();
}
int main() {
backend_t backend = make_js_file_backend(NULL);
// Create a new backend file under root.
int fd = wasmfs_create_file("/testfile", 0777, backend);
// Ensure that the size of the backend file is zero.
struct stat file;
assert(fstat(fd, &file) != -1);
assert(file.st_size == 0);
// Try writing to and reading from the file.
const char* msg = "Test with a new backend file\n";
write_and_read(msg, fd, msg);
// Verify that the size of the backend File is the same as the written buffer.
assert(fstat(fd, &file) != -1);
assert(file.st_size == strlen(msg));
// Try seeking to the beginning of the file and overwriting its contents.
assert(lseek(fd, 0, SEEK_SET) != -1);
write_and_read(msg, fd, msg);
// Try appending to the end of the backend File.
write_and_read(
msg, fd, "Test with a new backend file\nTest with a new backend file\n");
// Verify that the size of the backend File has increased.
assert(fstat(fd, &file) != -1);
assert(file.st_size == strlen(msg) * 2);
close(fd);
assert(unlink("/testfile") != -1);
// Try creating a new backend directory under root.
assert(wasmfs_create_directory("/test-dir", 0777, backend) != -1);
// Try to create a new backend file under this new directory.
int fd2 = open("/test-dir/backendfile", O_RDWR | O_CREAT, 0777);
// Try writing to and reading from the file.
const char* msg2 =
"Test with a backend file created under a backend directory\n";
write_and_read(msg2, fd2, msg2);
// Check that the backend file has the correct backend type.
assert(wasmfs_get_backend_by_fd(fd2) == backend);
// Try creating an in-memory file under a backend directory.
backend_t memoryBackend = wasmfs_get_backend_by_path("/");
int fd3 = wasmfs_create_file("/test-dir/inmemoryfile", 0777, memoryBackend);
const char* msg3 =
"Test with an in-memory file created under a backend directory\n";
write_and_read(msg3, fd3, msg3);
// Create a new backend file under root.
int fd4 = wasmfs_create_file("/testfile2", 0777, backend);
const char* msg4 = "Test with a backend file created under root\n";
// Try setting the file offset to an arbitrary value.
assert(lseek(fd4, 10, SEEK_SET) != -1);
char buf[200] = {};
errno = 0;
write(fd4, msg4, strlen(msg4));
assert(errno == 0);
errno = 0;
lseek(fd4, 0, SEEK_SET);
assert(errno == 0);
int bytesRead = read(fd4, buf, sizeof(buf));
for (ssize_t i = 0; i < bytesRead; i++) {
if (buf[i] == 0) {
printf("\\0");
} else {
printf("%c", buf[i]);
}
}
printf("\n");
// Check the size.
int result = lseek(fd4, 0, SEEK_END);
assert(result != -1);
printf("size: %lld\n", lseek(fd4, 0, SEEK_CUR));
// Resize.
result = ftruncate(fd4, 42);
assert(!result);
result = lseek(fd4, 0, SEEK_END);
assert(result != -1);
printf("resize: %lld\n", lseek(fd4, 0, SEEK_CUR));
// Check the contents remain after the resize (but are a tad shorter).
lseek(fd4, 0, SEEK_SET);
assert(errno == 0);
bytesRead = read(fd4, buf, sizeof(buf));
for (ssize_t i = 0; i < bytesRead; i++) {
if (buf[i] == 0) {
printf("\\0");
} else {
printf("%c", buf[i]);
}
}
printf("\n");
puts("\ndone.");
return 0;
}
|
