1/*
2 * Copyright 2010-2019 Amazon.com, Inc. or its affiliates. All Rights Reserved.
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License").
5 * You may not use this file except in compliance with the License.
6 * A copy of the License is located at
7 *
8 * http://aws.amazon.com/apache2.0
9 *
10 * or in the "license" file accompanying this file. This file is distributed
11 * on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
12 * express or implied. See the License for the specific language governing
13 * permissions and limitations under the License.
14 */
15
16#include <aws/common/log_writer.h>
17
18#include <aws/common/string.h>
19
20#include <errno.h>
21#include <stdio.h>
22
23#ifdef _MSC_VER
24# pragma warning(disable : 4996) /* Disable warnings about fopen() being insecure */
25#endif /* _MSC_VER */
26
27/*
28 * Basic log writer implementations - stdout, stderr, arbitrary file
29 */
30
31struct aws_file_writer;
32
33struct aws_file_writer {
34 FILE *log_file;
35 bool close_file_on_cleanup;
36};
37
38static int s_aws_file_writer_write(struct aws_log_writer *writer, const struct aws_string *output) {
39 struct aws_file_writer *impl = (struct aws_file_writer *)writer->impl;
40
41 size_t length = output->len;
42 if (fwrite(output->bytes, 1, length, impl->log_file) < length) {
43 return aws_translate_and_raise_io_error(errno);
44 }
45
46 return AWS_OP_SUCCESS;
47}
48
49static void s_aws_file_writer_clean_up(struct aws_log_writer *writer) {
50 struct aws_file_writer *impl = (struct aws_file_writer *)writer->impl;
51
52 if (impl->close_file_on_cleanup) {
53 fclose(impl->log_file);
54 }
55
56 aws_mem_release(writer->allocator, impl);
57}
58
59static struct aws_log_writer_vtable s_aws_file_writer_vtable = {
60 .write = s_aws_file_writer_write,
61 .clean_up = s_aws_file_writer_clean_up,
62};
63
64/*
65 * Shared internal init implementation
66 */
67static int s_aws_file_writer_init_internal(
68 struct aws_log_writer *writer,
69 struct aws_allocator *allocator,
70 const char *file_name_to_open,
71 FILE *currently_open_file) {
72
73 /* One or the other should be set */
74 if (!((file_name_to_open != NULL) ^ (currently_open_file != NULL))) {
75 return aws_raise_error(AWS_ERROR_INVALID_ARGUMENT);
76 }
77
78 /* Allocate and initialize the file writer */
79 struct aws_file_writer *impl = aws_mem_calloc(allocator, 1, sizeof(struct aws_file_writer));
80 if (impl == NULL) {
81 return AWS_OP_ERR;
82 }
83
84 impl->log_file = NULL;
85 impl->close_file_on_cleanup = false;
86
87 /* Open file if name passed in */
88 if (file_name_to_open != NULL) {
89 impl->log_file = fopen(file_name_to_open, "a+");
90 if (impl->log_file == NULL) {
91 aws_mem_release(allocator, impl);
92 return aws_translate_and_raise_io_error(errno);
93 }
94 impl->close_file_on_cleanup = true;
95 } else {
96 impl->log_file = currently_open_file;
97 }
98
99 writer->vtable = &s_aws_file_writer_vtable;
100 writer->allocator = allocator;
101 writer->impl = impl;
102
103 return AWS_OP_SUCCESS;
104}
105
106/*
107 * Public initialization interface
108 */
109int aws_log_writer_init_stdout(struct aws_log_writer *writer, struct aws_allocator *allocator) {
110 return s_aws_file_writer_init_internal(writer, allocator, NULL, stdout);
111}
112
113int aws_log_writer_init_stderr(struct aws_log_writer *writer, struct aws_allocator *allocator) {
114 return s_aws_file_writer_init_internal(writer, allocator, NULL, stderr);
115}
116
117int aws_log_writer_init_file(
118 struct aws_log_writer *writer,
119 struct aws_allocator *allocator,
120 struct aws_log_writer_file_options *options) {
121 return s_aws_file_writer_init_internal(writer, allocator, options->filename, options->file);
122}
123
124void aws_log_writer_clean_up(struct aws_log_writer *writer) {
125 AWS_ASSERT(writer->vtable->clean_up);
126 (writer->vtable->clean_up)(writer);
127}
128