Source/cmFilePathChecksum.cxx

   1 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
   2    file Copyright.txt or https://cmake.org/licensing for details.  */
   3 #include "cmFilePathChecksum.h"
   4
   5 #include <vector>
   6
   7 #include "cmBase32.h"
   8 #include "cmCryptoHash.h"
   9 #include "cmMakefile.h"
  10 #include "cmSystemTools.h"
  11
  12 cmFilePathChecksum::cmFilePathChecksum() = default;
  13
  14 cmFilePathChecksum::cmFilePathChecksum(std::string const& currentSrcDir,
  15                                        std::string const& currentBinDir,
  16                                        std::string const& projectSrcDir,
  17                                        std::string const& projectBinDir)
  18 {
  19   this->setupParentDirs(currentSrcDir, currentBinDir, projectSrcDir,
  20                         projectBinDir);
  21 }
  22
  23 cmFilePathChecksum::cmFilePathChecksum(cmMakefile* makefile)
  24 {
  25   this->setupParentDirs(makefile->GetCurrentSourceDirectory(),
  26                         makefile->GetCurrentBinaryDirectory(),
  27                         makefile->GetHomeDirectory(),
  28                         makefile->GetHomeOutputDirectory());
  29 }
  30
  31 void cmFilePathChecksum::setupParentDirs(std::string const& currentSrcDir,
  32                                          std::string const& currentBinDir,
  33                                          std::string const& projectSrcDir,
  34                                          std::string const& projectBinDir)
  35 {
  36   this->parentDirs[0].first = cmSystemTools::GetRealPath(currentSrcDir);
  37   this->parentDirs[1].first = cmSystemTools::GetRealPath(currentBinDir);
  38   this->parentDirs[2].first = cmSystemTools::GetRealPath(projectSrcDir);
  39   this->parentDirs[3].first = cmSystemTools::GetRealPath(projectBinDir);
  40
  41   this->parentDirs[0].second = "CurrentSource";
  42   this->parentDirs[1].second = "CurrentBinary";
  43   this->parentDirs[2].second = "ProjectSource";
  44   this->parentDirs[3].second = "ProjectBinary";
  45 }
  46
  47 std::string cmFilePathChecksum::get(std::string const& filePath) const
  48 {
  49   std::string relPath;
  50   std::string relSeed;
  51   {
  52     std::string const fileReal = cmSystemTools::GetRealPath(filePath);
  53     std::string parentDir;
  54     // Find closest project parent directory
  55     for (auto const& pDir : this->parentDirs) {
  56       if (!pDir.first.empty() &&
  57           cmsys::SystemTools::IsSubDirectory(fileReal, pDir.first)) {
  58         parentDir = pDir.first;
  59         relSeed = pDir.second;
  60         break;
  61       }
  62     }
  63     // Use file system root as fallback parent directory
  64     if (parentDir.empty()) {
  65       relSeed = "FileSystemRoot";
  66       cmsys::SystemTools::SplitPathRootComponent(fileReal, &parentDir);
  67     }
  68     // Calculate relative path from project parent directory
  69     relPath = cmsys::SystemTools::RelativePath(
  70       parentDir, cmsys::SystemTools::GetParentDirectory(fileReal));
  71   }
  72
  73   // Calculate the file ( seed + relative path ) binary checksum
  74   std::vector<unsigned char> hashBytes =
  75     cmCryptoHash(cmCryptoHash::AlgoSHA256).ByteHashString(relSeed + relPath);
  76
  77   // Convert binary checksum to string
  78   return cmBase32Encoder().encodeString(hashBytes.data(), hashBytes.size(),
  79                                         false);
  80 }
  81
  82 std::string cmFilePathChecksum::getPart(std::string const& filePath,
  83                                         size_t length) const
  84 {
  85   return this->get(filePath).substr(0, length);
  86 }