1 /*
2 * Copyright (c) Huawei Technologies Co., Ltd. 2014-2020. All rights reserved.
3 * Licensed under Mulan PSL v2.
4 * You can use this software according to the terms and conditions of the Mulan PSL v2.
5 * You may obtain a copy of Mulan PSL v2 at:
6 * http://license.coscl.org.cn/MulanPSL2
7 * THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OF ANY KIND,
8 * EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO NON-INFRINGEMENT,
9 * MERCHANTABILITY OR FIT FOR A PARTICULAR PURPOSE.
10 * See the Mulan PSL v2 for more details.
11 * Description: gets_s function
12 * Author: lishunda
13 * Create: 2014-02-25
14 */
15
16 #include "securecutil.h"
17
18 /*
19 * The parameter size is buffer size in byte
20 */
SecTrimCRLF(char * buffer,size_t size)21 SECUREC_INLINE void SecTrimCRLF(char *buffer, size_t size)
22 {
23 size_t len = strlen(buffer);
24 --len; /* Unsigned integer wrapping is accepted and is checked afterwards */
25 while (len < size && (buffer[len] == '\r' || buffer[len] == '\n')) {
26 buffer[len] = '\0';
27 --len; /* Unsigned integer wrapping is accepted and is checked next loop */
28 }
29 }
30
31 /*
32 * <FUNCTION DESCRIPTION>
33 * The gets_s function reads at most one less than the number of characters
34 * specified by destMax from the std input stream, into the array pointed to by buffer
35 * The line consists of all characters up to and including
36 * the first newline character ('\n'). gets_s then replaces the newline
37 * character with a null character ('\0') before returning the line.
38 * If the first character read is the end-of-file character, a null character
39 * is stored at the beginning of buffer and NULL is returned.
40 *
41 * <INPUT PARAMETERS>
42 * buffer Storage location for input string.
43 * destMax The size of the buffer.
44 *
45 * <OUTPUT PARAMETERS>
46 * buffer is updated
47 *
48 * <RETURN VALUE>
49 * buffer Successful operation
50 * NULL Improper parameter or read fail
51 */
gets_s(char * buffer,size_t destMax)52 char *gets_s(char *buffer, size_t destMax)
53 {
54 #ifdef SECUREC_COMPATIBLE_WIN_FORMAT
55 size_t bufferSize = ((destMax == (size_t)(-1)) ? SECUREC_STRING_MAX_LEN : destMax);
56 #else
57 size_t bufferSize = destMax;
58 #endif
59
60 if (buffer == NULL || bufferSize == 0 || bufferSize > SECUREC_STRING_MAX_LEN) {
61 SECUREC_ERROR_INVALID_PARAMTER("gets_s");
62 return NULL;
63 }
64
65 if (fgets(buffer, (int)bufferSize, SECUREC_STREAM_STDIN) != NULL) {
66 SecTrimCRLF(buffer, bufferSize);
67 return buffer;
68 }
69
70 return NULL;
71 }
72
73