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: vsnprintf_s function
12 * Author: lishunda
13 * Create: 2014-02-25
14 */
15
16 #include "secureprintoutput.h"
17
18 #if SECUREC_ENABLE_VSNPRINTF
19 /*
20 * <FUNCTION DESCRIPTION>
21 * The vsnprintf_s function is equivalent to the vsnprintf function
22 * except for the parameter destMax/count and the explicit runtime-constraints violation
23 * The vsnprintf_s function takes a pointer to an argument list, then formats
24 * and writes up to count characters of the given data to the memory pointed
25 * to by strDest and appends a terminating null.
26 *
27 * <INPUT PARAMETERS>
28 * strDest Storage location for the output.
29 * destMax The size of the strDest for output.
30 * count Maximum number of character to write(not including
31 * the terminating NULL)
32 * format Format-control string.
33 * argList pointer to list of arguments.
34 *
35 * <OUTPUT PARAMETERS>
36 * strDest is updated
37 *
38 * <RETURN VALUE>
39 * return the number of characters written, not including the terminating null
40 * return -1 if an error occurs.
41 * return -1 if count < destMax and the output string has been truncated
42 *
43 * If there is a runtime-constraint violation, strDest[0] will be set to the '\0' when strDest and destMax valid
44 */
vsnprintf_s(char * strDest,size_t destMax,size_t count,const char * format,va_list argList)45 int vsnprintf_s(char *strDest, size_t destMax, size_t count, const char *format, va_list argList)
46 {
47 int retVal;
48
49 if (SECUREC_VSNPRINTF_PARAM_ERROR(format, strDest, destMax, count, SECUREC_STRING_MAX_LEN)) {
50 SECUREC_VSPRINTF_CLEAR_DEST(strDest, destMax, SECUREC_STRING_MAX_LEN);
51 SECUREC_ERROR_INVALID_PARAMTER("vsnprintf_s");
52 return -1;
53 }
54
55 if (destMax > count) {
56 retVal = SecVsnprintfImpl(strDest, count + 1, format, argList);
57 if (retVal == SECUREC_PRINTF_TRUNCATE) { /* To keep dest buffer not destroyed 2014.2.18 */
58 /* The string has been truncated, return -1 */
59 return -1; /* To skip error handler, return strlen(strDest) or -1 */
60 }
61 } else {
62 retVal = SecVsnprintfImpl(strDest, destMax, format, argList);
63 #ifdef SECUREC_COMPATIBLE_WIN_FORMAT
64 if (retVal == SECUREC_PRINTF_TRUNCATE && count == (size_t)(-1)) {
65 return -1;
66 }
67 #endif
68 }
69
70 if (retVal < 0) {
71 strDest[0] = '\0'; /* Empty the dest strDest */
72 if (retVal == SECUREC_PRINTF_TRUNCATE) {
73 /* Buffer too small */
74 SECUREC_ERROR_INVALID_RANGE("vsnprintf_s");
75 }
76 SECUREC_ERROR_INVALID_PARAMTER("vsnprintf_s");
77 return -1;
78 }
79
80 return retVal;
81 }
82 #if SECUREC_IN_KERNEL
83 EXPORT_SYMBOL(vsnprintf_s);
84 #endif
85 #endif
86
87 #if SECUREC_SNPRINTF_TRUNCATED
88 /*
89 * <FUNCTION DESCRIPTION>
90 * The vsnprintf_truncated_s function is equivalent to the vsnprintf function
91 * except for the parameter destMax/count and the explicit runtime-constraints violation
92 * The vsnprintf_truncated_s function takes a pointer to an argument list, then formats
93 * and writes up to count characters of the given data to the memory pointed
94 * to by strDest and appends a terminating null.
95 *
96 * <INPUT PARAMETERS>
97 * strDest Storage location for the output.
98 * destMax The size of the strDest for output.
99 * the terminating NULL)
100 * format Format-control string.
101 * argList pointer to list of arguments.
102 *
103 * <OUTPUT PARAMETERS>
104 * strDest is updated
105 *
106 * <RETURN VALUE>
107 * return the number of characters written, not including the terminating null
108 * return -1 if an error occurs.
109 * return destMax-1 if output string has been truncated
110 *
111 * If there is a runtime-constraint violation, strDest[0] will be set to the '\0' when strDest and destMax valid
112 */
vsnprintf_truncated_s(char * strDest,size_t destMax,const char * format,va_list argList)113 int vsnprintf_truncated_s(char *strDest, size_t destMax, const char *format, va_list argList)
114 {
115 int retVal;
116
117 if (SECUREC_VSPRINTF_PARAM_ERROR(format, strDest, destMax, SECUREC_STRING_MAX_LEN)) {
118 SECUREC_VSPRINTF_CLEAR_DEST(strDest, destMax, SECUREC_STRING_MAX_LEN);
119 SECUREC_ERROR_INVALID_PARAMTER("vsnprintf_truncated_s");
120 return -1;
121 }
122
123 retVal = SecVsnprintfImpl(strDest, destMax, format, argList);
124 if (retVal < 0) {
125 if (retVal == SECUREC_PRINTF_TRUNCATE) {
126 return (int)(destMax - 1); /* To skip error handler, return strlen(strDest) */
127 }
128 strDest[0] = '\0'; /* Empty the dest strDest */
129 SECUREC_ERROR_INVALID_PARAMTER("vsnprintf_truncated_s");
130 return -1;
131 }
132
133 return retVal;
134 }
135 #if SECUREC_IN_KERNEL
136 EXPORT_SYMBOL(vsnprintf_truncated_s);
137 #endif
138 #endif
139
140