1 //===-- UUID.cpp ----------------------------------------------------------===//
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 #include "lldb/Utility/UUID.h"
10 
11 #include "lldb/Utility/Stream.h"
12 #include "llvm/ADT/StringRef.h"
13 #include "llvm/Support/Format.h"
14 
15 #include <ctype.h>
16 #include <stdio.h>
17 #include <string.h>
18 
19 using namespace lldb_private;
20 
21 // Whether to put a separator after count uuid bytes.
22 // For the first 16 bytes we follow the traditional UUID format. After that, we
23 // simply put a dash after every 6 bytes.
24 static inline bool separate(size_t count) {
25   if (count >= 10)
26     return (count - 10) % 6 == 0;
27 
28   switch (count) {
29   case 4:
30   case 6:
31   case 8:
32     return true;
33   default:
34     return false;
35   }
36 }
37 
38 UUID UUID::fromCvRecord(UUID::CvRecordPdb70 debug_info) {
39   llvm::sys::swapByteOrder(debug_info.Uuid.Data1);
40   llvm::sys::swapByteOrder(debug_info.Uuid.Data2);
41   llvm::sys::swapByteOrder(debug_info.Uuid.Data3);
42   llvm::sys::swapByteOrder(debug_info.Age);
43   if (debug_info.Age)
44     return UUID::fromOptionalData(&debug_info, sizeof(debug_info));
45   return UUID::fromOptionalData(&debug_info.Uuid, sizeof(debug_info.Uuid));
46 }
47 
48 std::string UUID::GetAsString(llvm::StringRef separator) const {
49   std::string result;
50   llvm::raw_string_ostream os(result);
51 
52   for (auto B : llvm::enumerate(GetBytes())) {
53     if (separate(B.index()))
54       os << separator;
55 
56     os << llvm::format_hex_no_prefix(B.value(), 2, true);
57   }
58   os.flush();
59 
60   return result;
61 }
62 
63 void UUID::Dump(Stream *s) const { s->PutCString(GetAsString()); }
64 
65 static inline int xdigit_to_int(char ch) {
66   ch = tolower(ch);
67   if (ch >= 'a' && ch <= 'f')
68     return 10 + ch - 'a';
69   return ch - '0';
70 }
71 
72 llvm::StringRef
73 UUID::DecodeUUIDBytesFromString(llvm::StringRef p,
74                                 llvm::SmallVectorImpl<uint8_t> &uuid_bytes) {
75   uuid_bytes.clear();
76   while (p.size() >= 2) {
77     if (isxdigit(p[0]) && isxdigit(p[1])) {
78       int hi_nibble = xdigit_to_int(p[0]);
79       int lo_nibble = xdigit_to_int(p[1]);
80       // Translate the two hex nibble characters into a byte
81       uuid_bytes.push_back((hi_nibble << 4) + lo_nibble);
82 
83       // Skip both hex digits
84       p = p.drop_front(2);
85     } else if (p.front() == '-') {
86       // Skip dashes
87       p = p.drop_front();
88     } else {
89       // UUID values can only consist of hex characters and '-' chars
90       break;
91     }
92   }
93   return p;
94 }
95 
96 bool UUID::SetFromStringRef(llvm::StringRef str) {
97   llvm::StringRef p = str;
98 
99   // Skip leading whitespace characters
100   p = p.ltrim();
101 
102   llvm::SmallVector<uint8_t, 20> bytes;
103   llvm::StringRef rest = UUID::DecodeUUIDBytesFromString(p, bytes);
104 
105   // Return false if we could not consume the entire string or if the parsed
106   // UUID is empty.
107   if (!rest.empty() || bytes.empty())
108     return false;
109 
110   *this = fromData(bytes);
111   return true;
112 }
113 
114 bool UUID::SetFromOptionalStringRef(llvm::StringRef str) {
115   bool result = SetFromStringRef(str);
116   if (result) {
117     if (llvm::all_of(m_bytes, [](uint8_t b) { return b == 0; }))
118         Clear();
119   }
120 
121   return result;
122 }
123