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
|
/**
* Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
* SPDX-License-Identifier: Apache-2.0.
*/
#include <aws/io/shared_library.h>
#include <aws/io/logging.h>
#include <dlfcn.h>
static const char *s_null = "<NULL>";
static const char *s_unknown_error = "<Unknown>";
int aws_shared_library_init(struct aws_shared_library *library, const char *library_path) {
AWS_ZERO_STRUCT(*library);
library->library_handle = dlopen(library_path, RTLD_LAZY);
if (library->library_handle == NULL) {
const char *error = dlerror();
AWS_LOGF_ERROR(
AWS_LS_IO_SHARED_LIBRARY,
"id=%p: Failed to load shared library at path \"%s\" with error: %s",
(void *)library,
library_path ? library_path : s_null,
error ? error : s_unknown_error);
return aws_raise_error(AWS_IO_SHARED_LIBRARY_LOAD_FAILURE);
}
return AWS_OP_SUCCESS;
}
void aws_shared_library_clean_up(struct aws_shared_library *library) {
if (library && library->library_handle) {
dlclose(library->library_handle);
library->library_handle = NULL;
}
}
int aws_shared_library_find_function(
struct aws_shared_library *library,
const char *symbol_name,
aws_generic_function *function_address) {
if (library == NULL || library->library_handle == NULL) {
return aws_raise_error(AWS_IO_SHARED_LIBRARY_FIND_SYMBOL_FAILURE);
}
/*
* Suggested work around for (undefined behavior) cast from void * to function pointer
* in POSIX.1-2003 standard, at least according to dlsym man page code sample.
*/
*(void **)(function_address) = dlsym(library->library_handle, symbol_name);
if (*function_address == NULL) {
const char *error = dlerror();
AWS_LOGF_ERROR(
AWS_LS_IO_SHARED_LIBRARY,
"id=%p: Failed to find shared library symbol \"%s\" with error: %s",
(void *)library,
symbol_name ? symbol_name : s_null,
error ? error : s_unknown_error);
return aws_raise_error(AWS_IO_SHARED_LIBRARY_FIND_SYMBOL_FAILURE);
}
return AWS_OP_SUCCESS;
}
|