[Dependency Scanning] Refactor string implementation to always malloc and tie lifetime to owning object.

Author: artemcm

include/swift-c/DependencyScan/DSString.h

@@ -18,7 +18,6 @@
 #ifndef SWIFT_C_DEPENDENCY_SCAN_H
 #define SWIFT_C_DEPENDENCY_SCAN_H
 
-#include "DSString.h"
 #include "DependencyScanMacros.h"
 #include <stdbool.h>
 #include <stddef.h>
@@ -34,6 +33,22 @@ SWIFTSCAN_BEGIN_DECLS
 
 //=== Public Scanner Data Types -------------------------------------------===//
 
+/**
+ * A character string used to pass around dependency scan result metadata.
+ * Lifetime of the string is strictly tied to the object whose field it represents.
+ * When the owning object is released, string memory is freed. Use \c
+ * swiftscan_get_C_string() to retrieve the string data.
+ */
+typedef struct {
+  const void *data;
+  unsigned length;
+} swiftscan_string_ref_t;
+
+typedef struct {
+  swiftscan_string_ref_t *strings;
+  unsigned count;
+} swiftscan_string_set_t;
+
 typedef enum {
   SWIFTSCAN_DEPENDENCY_INFO_SWIFT_TEXTUAL = 0,
   SWIFTSCAN_DEPENDENCY_INFO_SWIFT_BINARY = 1,
@@ -80,9 +95,15 @@ typedef struct {
 /// scan (command line arguments, working directory, etc.)
 typedef struct swiftscan_scan_invocation_s *swiftscan_scan_invocation_t;
 
+//=== String Functions ----------------------------------------------------===//
+
+/// Retrieve the character data associated with the given string.
+SWIFTSCAN_PUBLIC const char *
+swiftscan_get_C_string(swiftscan_string_ref_t string);
+
 //=== Dependency Result Functions -----------------------------------------===//
 
-SWIFTSCAN_PUBLIC swiftscan_string_t
+SWIFTSCAN_PUBLIC swiftscan_string_ref_t
 swiftscan_dependency_result_get_main_module_name(
     swiftscan_dependency_result_t result);
 
@@ -92,10 +113,10 @@ swiftscan_dependency_result_get_module_set(
 
 //=== Dependency Module Info Functions ------------------------------------===//
 
-SWIFTSCAN_PUBLIC swiftscan_string_t
+SWIFTSCAN_PUBLIC swiftscan_string_ref_t
 swiftscan_module_info_get_module_name(swiftscan_dependency_info_t info);
 
-SWIFTSCAN_PUBLIC swiftscan_string_t
+SWIFTSCAN_PUBLIC swiftscan_string_ref_t
 swiftscan_module_info_get_module_path(swiftscan_dependency_info_t info);
 
 SWIFTSCAN_PUBLIC swiftscan_string_set_t *
@@ -113,15 +134,15 @@ SWIFTSCAN_PUBLIC swiftscan_dependency_info_kind_t
 swiftscan_module_detail_get_kind(swiftscan_module_details_t details);
 
 //=== Swift Textual Module Details query APIs -----------------------------===//
-SWIFTSCAN_PUBLIC swiftscan_string_t
+SWIFTSCAN_PUBLIC swiftscan_string_ref_t
 swiftscan_swift_textual_detail_get_module_interface_path(
     swiftscan_module_details_t details);
 
 SWIFTSCAN_PUBLIC swiftscan_string_set_t *
 swiftscan_swift_textual_detail_get_compiled_module_candidates(
     swiftscan_module_details_t details);
 
-SWIFTSCAN_PUBLIC swiftscan_string_t
+SWIFTSCAN_PUBLIC swiftscan_string_ref_t
 swiftscan_swift_textual_detail_get_bridging_header_path(
     swiftscan_module_details_t details);
 
@@ -141,7 +162,7 @@ SWIFTSCAN_PUBLIC swiftscan_string_set_t *
 swiftscan_swift_textual_detail_get_extra_pcm_args(
     swiftscan_module_details_t details);
 
-SWIFTSCAN_PUBLIC swiftscan_string_t
+SWIFTSCAN_PUBLIC swiftscan_string_ref_t
 swiftscan_swift_textual_detail_get_context_hash(
     swiftscan_module_details_t details);
 
@@ -150,49 +171,49 @@ SWIFTSCAN_PUBLIC bool swiftscan_swift_textual_detail_get_is_framework(
 
 //=== Swift Binary Module Details query APIs ------------------------------===//
 
-SWIFTSCAN_PUBLIC swiftscan_string_t
+SWIFTSCAN_PUBLIC swiftscan_string_ref_t
 swiftscan_swift_binary_detail_get_compiled_module_path(
     swiftscan_module_details_t details);
 
-SWIFTSCAN_PUBLIC swiftscan_string_t
+SWIFTSCAN_PUBLIC swiftscan_string_ref_t
 swiftscan_swift_binary_detail_get_module_doc_path(
     swiftscan_module_details_t details);
 
-SWIFTSCAN_PUBLIC swiftscan_string_t
+SWIFTSCAN_PUBLIC swiftscan_string_ref_t
 swiftscan_swift_binary_detail_get_module_source_info_path(
     swiftscan_module_details_t details);
 
 //=== Swift Placeholder Module Details query APIs -------------------------===//
 
-SWIFTSCAN_PUBLIC swiftscan_string_t
+SWIFTSCAN_PUBLIC swiftscan_string_ref_t
 swiftscan_swift_placeholder_detail_get_compiled_module_path(
     swiftscan_module_details_t details);
 
-SWIFTSCAN_PUBLIC swiftscan_string_t
+SWIFTSCAN_PUBLIC swiftscan_string_ref_t
 swiftscan_swift_placeholder_detail_get_module_doc_path(
     swiftscan_module_details_t details);
 
-SWIFTSCAN_PUBLIC swiftscan_string_t
+SWIFTSCAN_PUBLIC swiftscan_string_ref_t
 swiftscan_swift_placeholder_detail_get_module_source_info_path(
     swiftscan_module_details_t details);
 
 //=== Clang Module Details query APIs -------------------------------------===//
 
-SWIFTSCAN_PUBLIC swiftscan_string_t
+SWIFTSCAN_PUBLIC swiftscan_string_ref_t
 swiftscan_clang_detail_get_module_map_path(swiftscan_module_details_t details);
 
-SWIFTSCAN_PUBLIC swiftscan_string_t
+SWIFTSCAN_PUBLIC swiftscan_string_ref_t
 swiftscan_clang_detail_get_context_hash(swiftscan_module_details_t details);
 
 SWIFTSCAN_PUBLIC swiftscan_string_set_t *
 swiftscan_clang_detail_get_command_line(swiftscan_module_details_t details);
 
 //=== Batch Scan Entry Functions ------------------------------------------===//
 
-SWIFTSCAN_PUBLIC swiftscan_string_t
+SWIFTSCAN_PUBLIC swiftscan_string_ref_t
 swiftscan_batch_scan_entry_get_module_name(swiftscan_batch_scan_entry_t entry);
 
-SWIFTSCAN_PUBLIC swiftscan_string_t
+SWIFTSCAN_PUBLIC swiftscan_string_ref_t
 swiftscan_batch_scan_entry_get_arguments(swiftscan_batch_scan_entry_t entry);
 
 SWIFTSCAN_PUBLIC bool
@@ -209,13 +230,13 @@ SWIFTSCAN_PUBLIC swiftscan_scan_invocation_t swiftscan_scan_invocation_create();
 
 SWIFTSCAN_PUBLIC void swiftscan_scan_invocation_set_working_directory(
     swiftscan_scan_invocation_t invocation,
-    swiftscan_string_t working_directory);
+    swiftscan_string_ref_t working_directory);
 
 SWIFTSCAN_PUBLIC void
 swiftscan_scan_invocation_set_argv(swiftscan_scan_invocation_t invocation,
                                    swiftscan_string_set_t *argv);
 
-SWIFTSCAN_PUBLIC swiftscan_string_t
+SWIFTSCAN_PUBLIC swiftscan_string_ref_t
 swiftscan_scan_invocation_get_working_directory(
     swiftscan_scan_invocation_t invocation);
 

include/swift-c/DependencyScan/DependencyScan.h

@@ -22,11 +22,11 @@ namespace swift {
 namespace dependencies {
 class DependencyScanningTool;
 }
-}
+} // namespace swift
 
 struct swiftscan_dependency_result_s {
   /// The name of the main module for this dependency graph (root node)
-  swiftscan_string_t main_module_name;
+  swiftscan_string_ref_t main_module_name;
 
   /// The complete list of modules discovered
   swiftscan_dependency_set_t *module_set;
@@ -41,10 +41,10 @@ struct swiftscan_dependency_info_s {
   /// "swiftBinary"
   /// "swiftPlaceholder"
   /// "clang""
-  swiftscan_string_t module_name;
+  swiftscan_string_ref_t module_name;
 
   /// The path for the module.
-  swiftscan_string_t module_path;
+  swiftscan_string_ref_t module_path;
 
   /// The source files used to build this module.
   swiftscan_string_set_t *source_files;
@@ -64,13 +64,13 @@ struct swiftscan_dependency_info_s {
 /// header.
 typedef struct {
   /// The module interface from which this module was built, if any.
-  swiftscan_string_t module_interface_path;
+  swiftscan_string_ref_t module_interface_path;
 
   /// The paths of potentially ready-to-use compiled modules for the interface.
   swiftscan_string_set_t *compiled_module_candidates;
 
   /// The bridging header, if any.
-  swiftscan_string_t bridging_header_path;
+  swiftscan_string_ref_t bridging_header_path;
 
   /// The source files referenced by the bridging header.
   swiftscan_string_set_t *bridging_source_files;
@@ -87,7 +87,7 @@ typedef struct {
   swiftscan_string_set_t *extra_pcm_args;
 
   /// The hash value that will be used for the generated module
-  swiftscan_string_t context_hash;
+  swiftscan_string_ref_t context_hash;
 
   /// A flag to indicate whether or not this module is a framework.
   bool is_framework;
@@ -96,35 +96,35 @@ typedef struct {
 /// Swift modules with only a binary module file.
 typedef struct {
   /// The path to the pre-compiled binary module
-  swiftscan_string_t compiled_module_path;
+  swiftscan_string_ref_t compiled_module_path;
 
   /// The path to the .swiftModuleDoc file.
-  swiftscan_string_t module_doc_path;
+  swiftscan_string_ref_t module_doc_path;
 
   /// The path to the .swiftSourceInfo file.
-  swiftscan_string_t module_source_info_path;
+  swiftscan_string_ref_t module_source_info_path;
 } swiftscan_swift_binary_details_t;
 
 /// Swift placeholder modules carry additional details that specify their
 /// module doc path and source info paths.
 typedef struct {
   /// The path to the pre-compiled binary module
-  swiftscan_string_t compiled_module_path;
+  swiftscan_string_ref_t compiled_module_path;
 
   /// The path to the .swiftModuleDoc file.
-  swiftscan_string_t module_doc_path;
+  swiftscan_string_ref_t module_doc_path;
 
   /// The path to the .swiftSourceInfo file.
-  swiftscan_string_t module_source_info_path;
+  swiftscan_string_ref_t module_source_info_path;
 } swiftscan_swift_placeholder_details_t;
 
 /// Clang modules are built from a module map file.
 typedef struct {
   /// The path to the module map used to build this module.
-  swiftscan_string_t module_map_path;
+  swiftscan_string_ref_t module_map_path;
 
   /// clang-generated context hash
-  swiftscan_string_t context_hash;
+  swiftscan_string_ref_t context_hash;
 
   /// Options to the compile command required to build this clang modulemap
   swiftscan_string_set_t *command_line;
@@ -138,11 +138,11 @@ struct swiftscan_module_details_s {
     swiftscan_swift_placeholder_details_t swift_placeholder_details;
     swiftscan_clang_details_t clang_details;
   };
-} ;
+};
 
 struct swiftscan_batch_scan_entry_s {
-  swiftscan_string_t module_name;
-  swiftscan_string_t arguments;
+  swiftscan_string_ref_t module_name;
+  swiftscan_string_ref_t arguments;
   bool is_swift;
 };
 
@@ -152,7 +152,7 @@ struct swiftscan_prescan_result_s {
 };
 
 struct swiftscan_scan_invocation_s {
-  swiftscan_string_t working_directory;
+  swiftscan_string_ref_t working_directory;
   swiftscan_string_set_t *argv;
 };
 

include/swift/DependencyScan/DSStringImpl.h

@@ -15,8 +15,8 @@
 
 #include "swift-c/DependencyScan/DependencyScan.h"
 #include "swift/AST/ModuleDependencies.h"
-#include "swift/Frontend/PrintingDiagnosticConsumer.h"
 #include "swift/DependencyScan/ScanDependencies.h"
+#include "swift/Frontend/PrintingDiagnosticConsumer.h"
 #include "llvm/ADT/StringSet.h"
 #include "llvm/Support/Error.h"
 #include "llvm/Support/StringSaver.h"