lldb/source/Utility/UUID.cpp

   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 <cctype>
  16 #include <cstdio>
  17 #include <cstring>
  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(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     *this = UUID(&debug_info, sizeof(debug_info));
  45   else
  46     *this = UUID(&debug_info.Uuid, sizeof(debug_info.Uuid));
  47 }
  48
  49 std::string UUID::GetAsString(llvm::StringRef separator) const {
  50   std::string result;
  51   llvm::raw_string_ostream os(result);
  52
  53   for (auto B : llvm::enumerate(GetBytes())) {
  54     if (separate(B.index()))
  55       os << separator;
  56
  57     os << llvm::format_hex_no_prefix(B.value(), 2, true);
  58   }
  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 = UUID(bytes);
 111   return true;
 112 }