1 //===-- StringExtractor.h ---------------------------------------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #ifndef LLDB_UTILITY_STRINGEXTRACTOR_H
10 #define LLDB_UTILITY_STRINGEXTRACTOR_H
11 
12 #include "llvm/ADT/ArrayRef.h"
13 #include "llvm/ADT/StringRef.h"
14 
15 #include <stddef.h>
16 #include <stdint.h>
17 #include <string>
18 
19 class StringExtractor {
20 public:
21   enum { BigEndian = 0, LittleEndian = 1 };
22   // Constructors and Destructors
23   StringExtractor();
24   StringExtractor(llvm::StringRef packet_str);
25   StringExtractor(const char *packet_cstr);
26   virtual ~StringExtractor();
27 
28   void Reset(llvm::StringRef str) {
29     m_packet = std::string(str);
30     m_index = 0;
31   }
32 
33   // Returns true if the file position is still valid for the data contained in
34   // this string extractor object.
35   bool IsGood() const { return m_index != UINT64_MAX; }
36 
37   uint64_t GetFilePos() const { return m_index; }
38 
39   void SetFilePos(uint32_t idx) { m_index = idx; }
40 
41   void Clear() {
42     m_packet.clear();
43     m_index = 0;
44   }
45 
46   void SkipSpaces();
47 
48   llvm::StringRef GetStringRef() const { return m_packet; }
49 
50   bool Empty() { return m_packet.empty(); }
51 
52   size_t GetBytesLeft() {
53     if (m_index < m_packet.size())
54       return m_packet.size() - m_index;
55     return 0;
56   }
57 
58   char GetChar(char fail_value = '\0');
59 
60   char PeekChar(char fail_value = '\0') {
61     const char *cstr = Peek();
62     if (cstr)
63       return cstr[0];
64     return fail_value;
65   }
66 
67   int DecodeHexU8();
68 
69   uint8_t GetHexU8(uint8_t fail_value = 0, bool set_eof_on_fail = true);
70 
71   bool GetHexU8Ex(uint8_t &ch, bool set_eof_on_fail = true);
72 
73   bool GetNameColonValue(llvm::StringRef &name, llvm::StringRef &value);
74 
75   int32_t GetS32(int32_t fail_value, int base = 0);
76 
77   uint32_t GetU32(uint32_t fail_value, int base = 0);
78 
79   int64_t GetS64(int64_t fail_value, int base = 0);
80 
81   uint64_t GetU64(uint64_t fail_value, int base = 0);
82 
83   uint32_t GetHexMaxU32(bool little_endian, uint32_t fail_value);
84 
85   uint64_t GetHexMaxU64(bool little_endian, uint64_t fail_value);
86 
87   size_t GetHexBytes(llvm::MutableArrayRef<uint8_t> dest,
88                      uint8_t fail_fill_value);
89 
90   size_t GetHexBytesAvail(llvm::MutableArrayRef<uint8_t> dest);
91 
92   size_t GetHexByteString(std::string &str);
93 
94   size_t GetHexByteStringFixedLength(std::string &str, uint32_t nibble_length);
95 
96   size_t GetHexByteStringTerminatedBy(std::string &str, char terminator);
97 
98   bool ConsumeFront(const llvm::StringRef &str);
99 
100   const char *Peek() {
101     if (m_index < m_packet.size())
102       return m_packet.c_str() + m_index;
103     return nullptr;
104   }
105 
106 protected:
107   bool fail() {
108     m_index = UINT64_MAX;
109     return false;
110   }
111 
112   /// The string in which to extract data.
113   std::string m_packet;
114 
115   /// When extracting data from a packet, this index will march along as things
116   /// get extracted. If set to UINT64_MAX the end of the packet data was
117   /// reached when decoding information.
118   uint64_t m_index;
119 };
120 
121 #endif // LLDB_UTILITY_STRINGEXTRACTOR_H
122