Merge pull request #9745 from github/alexdenisov/put-traps-into-a-temp-folder

Swift: store TRAP files in a temporary folder until the extraction is complete

Author: AlexDenisov

swift/extractor/SwiftExtractor.cpp

@@ -62,13 +62,13 @@ static void extractDeclarations(const SwiftExtractorConfiguration& config,
   // TODO: find a more robust approach to avoid collisions?
   llvm::StringRef filename = primaryFile ? primaryFile->getFilename() : module.getModuleFilename();
   std::string tempTrapName = filename.str() + '.' + std::to_string(getpid()) + ".trap";
-  llvm::SmallString<PATH_MAX> tempTrapPath(config.trapDir);
+  llvm::SmallString<PATH_MAX> tempTrapPath(config.tempTrapDir);
   llvm::sys::path::append(tempTrapPath, tempTrapName);
 
-  llvm::StringRef trapParent = llvm::sys::path::parent_path(tempTrapPath);
-  if (std::error_code ec = llvm::sys::fs::create_directories(trapParent)) {
-    std::cerr << "Cannot create trap directory '" << trapParent.str() << "': " << ec.message()
-              << "\n";
+  llvm::StringRef tempTrapParent = llvm::sys::path::parent_path(tempTrapPath);
+  if (std::error_code ec = llvm::sys::fs::create_directories(tempTrapParent)) {
+    std::cerr << "Cannot create temp trap directory '" << tempTrapParent.str()
+              << "': " << ec.message() << "\n";
     return;
   }
 
@@ -117,6 +117,13 @@ static void extractDeclarations(const SwiftExtractorConfiguration& config,
   llvm::SmallString<PATH_MAX> trapPath(config.trapDir);
   llvm::sys::path::append(trapPath, trapName);
 
+  llvm::StringRef trapParent = llvm::sys::path::parent_path(trapPath);
+  if (std::error_code ec = llvm::sys::fs::create_directories(trapParent)) {
+    std::cerr << "Cannot create trap directory '" << trapParent.str() << "': " << ec.message()
+              << "\n";
+    return;
+  }
+
   // TODO: The last process wins. Should we do better than that?
   if (std::error_code ec = llvm::sys::fs::rename(tempTrapPath, trapPath)) {
     std::cerr << "Cannot rename temp trap file '" << tempTrapPath.str().str() << "' -> '"

swift/extractor/SwiftExtractorConfiguration.h

@@ -9,7 +9,14 @@ struct SwiftExtractorConfiguration {
   std::string trapDir;
   // The location for storing extracted source files.
   std::string sourceArchiveDir;
-  // The arguments passed to the extractor. Used for debugging.
+  // A temporary directory that exists during database creation, but is deleted once the DB is
+  // finalized.
+  std::string scratchDir;
+  // A temporary directory that contains TRAP files before they are moved into their final destination.
+  // Subdirectory of the scratchDir.
+  std::string tempTrapDir;
+
+  // The original arguments passed to the extractor. Used for debugging.
   std::vector<std::string> frontendOptions;
 };
 }  // namespace codeql

swift/extractor/main.cpp

@@ -51,6 +51,10 @@ int main(int argc, char** argv) {
   codeql::SwiftExtractorConfiguration configuration{};
   configuration.trapDir = getenv_or("CODEQL_EXTRACTOR_SWIFT_TRAP_DIR", ".");
   configuration.sourceArchiveDir = getenv_or("CODEQL_EXTRACTOR_SWIFT_SOURCE_ARCHIVE_DIR", ".");
+  configuration.scratchDir = getenv_or("CODEQL_EXTRACTOR_SWIFT_SCRATCH_DIR", ".");
+
+  configuration.tempTrapDir = configuration.scratchDir + "/swift-trap-temp";
+
   std::vector<const char*> args;
   for (int i = 1; i < argc; i++) {
     args.push_back(argv[i]);