1 /*
2  * Copyright (c) 2023 Huawei Device Co., Ltd.
3  * Licensed under the Apache License, Version 2.0 (the "License");
4  * you may not use this file except in compliance with the License.
5  * You may obtain a copy of the License at
6  *
7  * http://www.apache.org/licenses/LICENSE-2.0
8  *
9  * Unless required by applicable law or agreed to in writing, software
10  * distributed under the License is distributed on an "AS IS" BASIS,
11  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12  * See the License for the specific language governing permissions and
13  * limitations under the License.
14  */
15 
16 #ifndef STRING_PRINTF_H
17 #define STRING_PRINTF_H
18 
19 #include <cstdint>
20 #include <cstdio>
21 #include <string>
22 #include <securec.h>
23 
24 namespace OHOS {
25 namespace HiviewDFX {
26 namespace {
27 const int STRING_BUF_LEN = 4096;
28 }
29 
BufferAppendV(char * buf,int size,const char * fmt,va_list ap)30 static int BufferAppendV(char *buf, int size, const char *fmt, va_list ap)
31 {
32     if (buf == nullptr || size <= 0) {
33         return -1;
34     }
35     int ret = vsnprintf_s(buf, size, size - 1, fmt, ap);
36     return ret;
37 }
38 
StringAppendV(std::string & dst,const char * fmt,va_list ap)39 static bool StringAppendV(std::string& dst, const char* fmt, va_list ap)
40 {
41     char buffer[STRING_BUF_LEN] = {0};
42     va_list bakAp;
43     va_copy(bakAp, ap);
44     int ret = BufferAppendV(buffer, sizeof(buffer), fmt, bakAp);
45     va_end(bakAp);
46     if (ret > 0) {
47         dst.append(buffer, ret);
48     }
49     return ret != -1;
50 }
51 
BufferPrintf(char * buf,size_t size,const char * fmt,...)52 inline int BufferPrintf(char *buf, size_t size, const char *fmt, ...)
53 {
54     va_list ap;
55     va_start(ap, fmt);
56     int ret = BufferAppendV(buf, size, fmt, ap);
57     va_end(ap);
58     return ret;
59 }
60 
61 inline std::string StringPrintf(const char *fmt, ...) __attribute__((format(printf, 1, 2)));
62 
StringPrintf(const char * fmt,...)63 inline std::string StringPrintf(const char *fmt, ...)
64 {
65     if (fmt == nullptr) {
66         return "";
67     }
68     std::string dst;
69     va_list ap;
70     va_start(ap, fmt);
71     StringAppendV(dst, fmt, ap);
72     va_end(ap);
73     return dst;
74 }
75 
StringAppendF(std::string & dst,const char * fmt,...)76 inline void StringAppendF(std::string& dst, const char* fmt, ...)
77 {
78     va_list ap;
79     va_start(ap, fmt);
80     StringAppendV(dst, fmt, ap);
81     va_end(ap);
82 }
83 } // namespace HiviewDFX
84 } // namespace OHOS
85 #endif
86