1 files changed, 299 insertions, 0 deletions
diff --git a/Source/cmFileAPI.cxx b/Source/cmFileAPI.cxx
new file mode 100644
index 0000000..23e0ced
--- /dev/null
+++ b/Source/cmFileAPI.cxx
@@ -0,0 +1,299 @@
+/* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
+   file Copyright.txt or https://cmake.org/licensing for details.  */
+#include "cmFileAPI.h"
+
+#include "cmCryptoHash.h"
+#include "cmSystemTools.h"
+#include "cmTimestamp.h"
+#include "cmake.h"
+#include "cmsys/Directory.hxx"
+#include "cmsys/FStream.hxx"
+
+#include <algorithm>
+#include <cassert>
+#include <chrono>
+#include <ctime>
+#include <iomanip>
+#include <sstream>
+#include <utility>
+
+cmFileAPI::cmFileAPI(cmake* cm)
+  : CMakeInstance(cm)
+{
+  this->APIv1 =
+    this->CMakeInstance->GetHomeOutputDirectory() + "/.cmake/api/v1";
+
+  Json::StreamWriterBuilder wbuilder;
+  wbuilder["indentation"] = "\t";
+  this->JsonWriter =
+    std::unique_ptr<Json::StreamWriter>(wbuilder.newStreamWriter());
+}
+
+void cmFileAPI::ReadQueries()
+{
+  std::string const query_dir = this->APIv1 + "/query";
+  this->QueryExists = cmSystemTools::FileIsDirectory(query_dir);
+  if (!this->QueryExists) {
+    return;
+  }
+
+  // Load queries at the top level.
+  std::vector<std::string> queries = cmFileAPI::LoadDir(query_dir);
+
+  // Read the queries and save for later.
+  for (std::string& query : queries) {
+    if (!cmFileAPI::ReadQuery(query, this->TopQuery.Known)) {
+      this->TopQuery.Unknown.push_back(std::move(query));
+    }
+  }
+}
+
+void cmFileAPI::WriteReplies()
+{
+  if (this->QueryExists) {
+    cmSystemTools::MakeDirectory(this->APIv1 + "/reply");
+    this->WriteJsonFile(this->BuildReplyIndex(), "index", ComputeSuffixTime);
+  }
+
+  this->RemoveOldReplyFiles();
+}
+
+std::vector<std::string> cmFileAPI::LoadDir(std::string const& dir)
+{
+  std::vector<std::string> files;
+  cmsys::Directory d;
+  d.Load(dir);
+  for (unsigned long i = 0; i < d.GetNumberOfFiles(); ++i) {
+    std::string f = d.GetFile(i);
+    if (f != "." && f != "..") {
+      files.push_back(std::move(f));
+    }
+  }
+  std::sort(files.begin(), files.end());
+  return files;
+}
+
+void cmFileAPI::RemoveOldReplyFiles()
+{
+  std::string const reply_dir = this->APIv1 + "/reply";
+  std::vector<std::string> files = this->LoadDir(reply_dir);
+  for (std::string const& f : files) {
+    if (this->ReplyFiles.find(f) == this->ReplyFiles.end()) {
+      std::string file = reply_dir + "/" + f;
+      cmSystemTools::RemoveFile(file);
+    }
+  }
+}
+
+std::string cmFileAPI::WriteJsonFile(
+  Json::Value const& value, std::string const& prefix,
+  std::string (*computeSuffix)(std::string const&))
+{
+  std::string fileName;
+
+  // Write the json file with a temporary name.
+  std::string const& tmpFile = this->APIv1 + "/tmp.json";
+  cmsys::ofstream ftmp(tmpFile.c_str());
+  this->JsonWriter->write(value, &ftmp);
+  ftmp << "\n";
+  ftmp.close();
+  if (!ftmp) {
+    cmSystemTools::RemoveFile(tmpFile);
+    return fileName;
+  }
+
+  // Compute the final name for the file.
+  fileName = prefix + "-" + computeSuffix(tmpFile) + ".json";
+
+  // Create the destination.
+  std::string file = this->APIv1 + "/reply";
+  cmSystemTools::MakeDirectory(file);
+  file += "/";
+  file += fileName;
+
+  // If the final name already exists then assume it has proper content.
+  // Otherwise, atomically place the reply file at its final name
+  if (cmSystemTools::FileExists(file, true) ||
+      !cmSystemTools::RenameFile(tmpFile.c_str(), file.c_str())) {
+    cmSystemTools::RemoveFile(tmpFile);
+  }
+
+  // Record this among files we have just written.
+  this->ReplyFiles.insert(fileName);
+
+  return fileName;
+}
+
+std::string cmFileAPI::ComputeSuffixHash(std::string const& file)
+{
+  cmCryptoHash hasher(cmCryptoHash::AlgoSHA3_256);
+  std::string hash = hasher.HashFile(file);
+  hash.resize(20, '0');
+  return hash;
+}
+
+std::string cmFileAPI::ComputeSuffixTime(std::string const&)
+{
+  std::chrono::milliseconds ms =
+    std::chrono::duration_cast<std::chrono::milliseconds>(
+      std::chrono::system_clock::now().time_since_epoch());
+  std::chrono::seconds s =
+    std::chrono::duration_cast<std::chrono::seconds>(ms);
+
+  std::time_t ts = s.count();
+  std::size_t tms = ms.count() % 1000;
+
+  cmTimestamp cmts;
+  std::ostringstream ss;
+  ss << cmts.CreateTimestampFromTimeT(ts, "%Y-%m-%dT%H-%M-%S", true) << '-'
+     << std::setfill('0') << std::setw(4) << tms;
+  return ss.str();
+}
+
+bool cmFileAPI::ReadQuery(std::string const& query,
+                          std::vector<Object>& objects)
+{
+  // Parse the "<kind>-" syntax.
+  std::string::size_type sep_pos = query.find('-');
+  if (sep_pos == std::string::npos) {
+    return false;
+  }
+  std::string kindName = query.substr(0, sep_pos);
+  std::string verStr = query.substr(sep_pos + 1);
+  if (kindName == ObjectKindName(ObjectKind::InternalTest)) {
+    Object o;
+    o.Kind = ObjectKind::InternalTest;
+    if (verStr == "v1") {
+      o.Version = 1;
+    } else if (verStr == "v2") {
+      o.Version = 2;
+    } else {
+      return false;
+    }
+    objects.push_back(o);
+    return true;
+  }
+  return false;
+}
+
+Json::Value cmFileAPI::BuildReplyIndex()
+{
+  Json::Value index(Json::objectValue);
+
+  // Report information about this version of CMake.
+  index["cmake"] = this->BuildCMake();
+
+  // Reply to all queries that we loaded.
+  index["reply"] = this->BuildReply(this->TopQuery);
+
+  // Move our index of generated objects into its field.
+  Json::Value& objects = index["objects"] = Json::arrayValue;
+  for (auto& entry : this->ReplyIndexObjects) {
+    objects.append(std::move(entry.second)); // NOLINT(*)
+  }
+
+  return index;
+}
+
+Json::Value cmFileAPI::BuildCMake()
+{
+  Json::Value cmake = Json::objectValue;
+  cmake["version"] = this->CMakeInstance->ReportVersionJson();
+  Json::Value& cmake_paths = cmake["paths"] = Json::objectValue;
+  cmake_paths["cmake"] = cmSystemTools::GetCMakeCommand();
+  cmake_paths["ctest"] = cmSystemTools::GetCTestCommand();
+  cmake_paths["cpack"] = cmSystemTools::GetCPackCommand();
+  cmake_paths["root"] = cmSystemTools::GetCMakeRoot();
+  return cmake;
+}
+
+Json::Value cmFileAPI::BuildReply(Query const& q)
+{
+  Json::Value reply = Json::objectValue;
+  for (Object const& o : q.Known) {
+    std::string const& name = ObjectName(o);
+    reply[name] = this->AddReplyIndexObject(o);
+  }
+
+  for (std::string const& name : q.Unknown) {
+    reply[name] = cmFileAPI::BuildReplyError("unknown query file");
+  }
+  return reply;
+}
+
+Json::Value cmFileAPI::BuildReplyError(std::string const& error)
+{
+  Json::Value e = Json::objectValue;
+  e["error"] = error;
+  return e;
+}
+
+Json::Value const& cmFileAPI::AddReplyIndexObject(Object const& o)
+{
+  Json::Value& indexEntry = this->ReplyIndexObjects[o];
+  if (!indexEntry.isNull()) {
+    // The reply object has already been generated.
+    return indexEntry;
+  }
+
+  // Generate this reply object.
+  Json::Value const& object = this->BuildObject(o);
+  assert(object.isObject());
+
+  // Populate this index entry.
+  indexEntry = Json::objectValue;
+  indexEntry["kind"] = object["kind"];
+  indexEntry["version"] = object["version"];
+  indexEntry["jsonFile"] = this->WriteJsonFile(object, ObjectName(o));
+  return indexEntry;
+}
+
+const char* cmFileAPI::ObjectKindName(ObjectKind kind)
+{
+  // Keep in sync with ObjectKind enum.
+  static const char* objectKindNames[] = {
+    "__test" //
+  };
+  return objectKindNames[size_t(kind)];
+}
+
+std::string cmFileAPI::ObjectName(Object const& o)
+{
+  std::string name = ObjectKindName(o.Kind);
+  name += "-v";
+  name += std::to_string(o.Version);
+  return name;
+}
+
+Json::Value cmFileAPI::BuildObject(Object const& object)
+{
+  Json::Value value;
+
+  switch (object.Kind) {
+    case ObjectKind::InternalTest:
+      value = this->BuildInternalTest(object);
+      break;
+  }
+
+  return value;
+}
+
+// The "__test" object kind is for internal testing of CMake.
+
+static unsigned int const InternalTestV1Minor = 3;
+static unsigned int const InternalTestV2Minor = 0;
+
+Json::Value cmFileAPI::BuildInternalTest(Object const& object)
+{
+  Json::Value test = Json::objectValue;
+  test["kind"] = this->ObjectKindName(object.Kind);
+  Json::Value& version = test["version"] = Json::objectValue;
+  if (object.Version == 2) {
+    version["major"] = 2;
+    version["minor"] = InternalTestV2Minor;
+  } else {
+    version["major"] = 1;
+    version["minor"] = InternalTestV1Minor;
+  }
+  return test;
+}