[Caching] Add new CacheReplay APIs to libSwiftScan

Add new APIs libSwiftScan that can be used for cache query and cache
replay. This enables swift-driver or build system to query the cache and
replay the compilation results without invocation swift-frontend for
better scheduling.

Author: cachemeifyoucan

include/swift-c/DependencyScan/DependencyScan.h

@@ -25,7 +25,7 @@
 /// SWIFTSCAN_VERSION_MINOR should increase when there are API additions.
 /// SWIFTSCAN_VERSION_MAJOR is intended for "major" source/ABI breaking changes.
 #define SWIFTSCAN_VERSION_MAJOR 0
-#define SWIFTSCAN_VERSION_MINOR 5
+#define SWIFTSCAN_VERSION_MINOR 6
 
 SWIFTSCAN_BEGIN_DECLS
 
@@ -441,6 +441,53 @@ typedef struct swiftscan_cas_options_s *swiftscan_cas_options_t;
 /// ActionCache.
 typedef struct swiftscan_cas_s *swiftscan_cas_t;
 
+/// Opaque container for a cached compilation.
+typedef struct swiftscan_cached_compilation_s *swiftscan_cached_compilation_t;
+
+/// Opaque type for a cache replay instance.
+typedef struct swiftscan_cache_replay_instance_s
+    *swiftscan_cache_replay_instance_t;
+
+/// Opaque type for a cancellation token for async cache operations.
+typedef struct swiftscan_cache_cancellation_token_s
+    *swiftscan_cache_cancellation_token_t;
+
+/// Enum types for output types for cache key computation.
+/// List should contain all the output file types, including supplemententary
+/// outputs, except diagnostics outputs, which are covered by cached diagnostic
+/// entry.
+typedef enum {
+  SWIFTSCAN_OUTPUT_TYPE_OBJECT = 0,
+  SWIFTSCAN_OUTPUT_TYPE_SWIFTMODULE = 1,
+  SWIFTSCAN_OUTPUT_TYPE_SWIFTINTERFACE = 2,
+  SWIFTSCAN_OUTPUT_TYPE_SWIFTPRIVATEINTERFACE = 3,
+  SWIFTSCAN_OUTPUT_TYPE_CLANG_MODULE = 4,
+  SWIFTSCAN_OUTPUT_TYPE_CLANG_PCH = 5,
+  SWIFTSCAN_OUTPUT_TYPE_CLANG_HEADER = 6,
+  SWIFTSCAN_OUTPUT_TYPE_SWIFT_SOURCE_INFO = 7,
+  SWIFTSCAN_OUTPUT_TYPE_SWIFT_MODULE_DOC = 8,
+  SWIFTSCAN_OUTPUT_TYPE_DEPENDENCIES = 9,
+  SWIFTSCAN_OUTPUT_TYPE_SWIFT_DEPS = 10,
+  SWIFTSCAN_OUTPUT_TYPE_MODULE_TRACE = 11,
+  SWIFTSCAN_OUTPUT_TYPE_TBD = 12,
+  SWIFTSCAN_OUTPUT_TYPE_SWIFT_MODULE_SUMMARY = 13,
+  SWIFTSCAN_OUTPUT_TYPE_SWIFT_ABI_DESCRIPTOR = 14,
+  SWIFTSCAN_OUTPUT_TYPE_SWIFT_API_DESCRIPTOR = 15,
+  SWIFTSCAN_OUTPUT_TYPE_CONST_VALUE = 16,
+  SWIFTSCAN_OUTPUT_TYPE_MODULE_SEMANTIC_INFO = 17,
+  SWIFTSCAN_OUTPUT_TYPE_YAML_OPT_RECORD = 18,
+  SWIFTSCAN_OUTPUT_TYPE_BITSTREAM_OPT_RECORD = 19,
+  SWIFTSCAN_OUTPUT_TYPE_CACHED_DIAGNOSTICS = 20,
+  SWIFTSCAN_OUTPUT_TYPE_LAST = SWIFTSCAN_OUTPUT_TYPE_CACHED_DIAGNOSTICS
+} swiftscan_output_kind_t;
+
+/// Enum types for cache result lookup or replay.
+typedef enum {
+  SWIFTSCAN_CACHE_RESULT_SUCCESS = 0,
+  SWIFTSCAN_CACHE_RESULT_NOT_FOUND = 1,
+  SWIFTSCAN_CACHE_RESULT_ERROR = 2,
+} swiftscan_cache_result_t;
+
 /// Create a \c CASOptions for creating CAS inside scanner specified.
 SWIFTSCAN_PUBLIC swiftscan_cas_options_t swiftscan_cas_options_create(void);
 
@@ -492,6 +539,130 @@ SWIFTSCAN_PUBLIC swiftscan_string_ref_t
 swiftscan_cache_compute_key(swiftscan_cas_t cas, int argc, const char **argv,
                             const char *input, swiftscan_string_ref_t *error);
 
+/// Query the result of the compilation using the output cache key. \c globally
+/// suggests if the lookup should check remote cache if such operation exists.
+/// Returns the CachedCompilation of the result if found, or nullptr if output
+/// is not found or an error occurs. When an error occurs, the error message is
+/// returned via \c error parameter and its caller needs to free the message
+/// using `swiftscan_string_dispose`. The returned CachedCompilation needs to be
+/// freed via `swiftscan_cached_compilation_dispose`.
+SWIFTSCAN_PUBLIC swiftscan_cached_compilation_t
+swiftscan_cache_query(swiftscan_cas_t cas, const char *key, bool globally,
+                      swiftscan_string_ref_t *error);
+
+/// Async version of `swiftscan_cache_query` where result is returned via
+/// callback. Both cache_result enum and CachedCompilation will be provided to
+/// callback. \c ctx is an opaque value that passed to the callback and \c
+/// swiftscan_cache_cancellation_token_t will return an token that can be used
+/// to cancel the async operation. The token needs to be freed by caller using
+/// `swiftscan_cache_cancellation_token_dispose`.
+SWIFTSCAN_PUBLIC void swiftscan_cache_query_async(
+    swiftscan_cas_t cas, const char *key, bool globally, void *ctx,
+    void (*callback)(void *ctx, swiftscan_cache_result_t,
+                     swiftscan_cached_compilation_t,
+                     swiftscan_string_ref_t error),
+    swiftscan_cache_cancellation_token_t *);
+
+/// Dispose a CachedCompilation.
+SWIFTSCAN_PUBLIC void
+    swiftscan_cached_compilation_dispose(swiftscan_cached_compilation_t);
+
+/// Download and materialized the CASObject referenced by the CASID in the local
+/// CAS if needed from a remote CAS.
+/// If the return value is SWIFTSCAN_CACHE_RESULT_ERROR, the error message is
+/// returned via \c error parameter and its caller needs to free the message
+/// using `swiftscan_string_dispose`.
+SWIFTSCAN_PUBLIC swiftscan_cache_result_t
+swiftscan_cache_load_cached_compilation(swiftscan_cas_t cas,
+                                        swiftscan_cached_compilation_t,
+                                        swiftscan_string_ref_t *error);
+
+/// Async version of `swiftscan_cache_load_cached_compilation` where result is
+/// returned via callback. \c ctx is an opaque value that passed to the callback
+/// and \c swiftscan_cache_cancellation_token_t will return an token that can be
+/// used to cancel the async operation. The token needs to be freed by caller
+/// using `swiftscan_cache_cancellation_token_dispose`.
+SWIFTSCAN_PUBLIC void swiftscan_cache_load_cached_compilation_async(
+    swiftscan_cas_t cas, swiftscan_cached_compilation_t, void *ctx,
+    void (*callback)(void *ctx, swiftscan_cache_result_t,
+                     swiftscan_string_ref_t error),
+    swiftscan_cache_cancellation_token_t *);
+
+/// Check if CachedCompilation is materialized locally and can be accessed
+/// without downloading.
+SWIFTSCAN_PUBLIC bool
+    swiftscan_cache_compilation_is_loaded(swiftscan_cached_compilation_t);
+
+/// Query the number of outputs from a cached compilation. The cached
+/// compilation needs to be loaded, otherwise will return error. The error
+/// message is returned via \c error parameter and its caller needs to free the
+/// message using `swiftscan_string_dispose`.
+SWIFTSCAN_PUBLIC unsigned
+swiftscan_cache_get_num_cached_outputs(swiftscan_cached_compilation_t,
+                                       swiftscan_string_ref_t *error);
+
+/// Query if the kind of otuput exists in a cached compilation. The cached
+/// compilation needs to be loaded, otherwise will return error. The error
+/// message is returned via \c error parameter and its caller needs to free the
+/// message using `swiftscan_string_dispose`.
+SWIFTSCAN_PUBLIC bool
+swiftscan_cache_compilation_has_output_kind(swiftscan_cached_compilation_t,
+                                            swiftscan_output_kind_t,
+                                            swiftscan_string_ref_t *error);
+
+/// Make the cache compilation available globally. \c callback will be called
+/// on completion.
+/// \c swiftscan_cache_cancellation_token_t will return an token that can be
+/// used to cancel the async operation. The token needs to be freed by caller
+/// using `swiftscan_cache_cancellation_token_dispose`.
+SWIFTSCAN_PUBLIC void swiftscan_cache_make_global_async(
+    swiftscan_cas_t cas, const char *key, void *ctx,
+    void (*callback)(void *ctx, swiftscan_string_ref_t error),
+    swiftscan_cache_cancellation_token_t *);
+
+/// Cancel the async cache action that is associated with token.
+SWIFTSCAN_PUBLIC void
+    swiftscan_cache_action_cancel(swiftscan_cache_cancellation_token_t);
+
+/// Dispose the cancellation token.
+SWIFTSCAN_PUBLIC void swiftscan_cache_cancellation_token_dispose(
+    swiftscan_cache_cancellation_token_t);
+
+/// Create a swift cached compilation replay instance with its command-line
+/// invocation. Return nullptr when errors occurs and the error message is
+/// returned via \c error parameter and its caller needs to free the message
+/// using `swiftscan_string_dispose`.
+SWIFTSCAN_PUBLIC swiftscan_cache_replay_instance_t
+swiftscan_cache_replay_instance_create(int argc, const char **argv,
+                                       swiftscan_string_ref_t *error);
+
+/// Dispose swift cached compilation replay instance.
+SWIFTSCAN_PUBLIC void
+    swiftscan_cache_replay_instance_dispose(swiftscan_cache_replay_instance_t);
+
+/// Replay the cached compilation using cached compliation replay instance.
+/// If the return value is SWIFTSCAN_CACHE_RESULT_ERROR, the error message is
+/// returned via \c error parameter and its caller needs to free the message
+/// using `swiftscan_string_dispose`.
+SWIFTSCAN_PUBLIC swiftscan_cache_result_t swiftscan_cache_replay_compilation(
+    swiftscan_cas_t cas, swiftscan_cache_replay_instance_t,
+    swiftscan_cached_compilation_t, swiftscan_string_ref_t *error);
+
+/// Async replay the cached compilation. Callback function will be provided
+/// by the cache replay result, and its stdout, stderr, and any error message.
+/// \c ctx is an opaque value that passed to the callback and
+/// \c swiftscan_cache_cancellation_token_t will return an token that can be
+/// used to cancel the async operation. The token needs to be freed by caller
+/// using `swiftscan_cache_cancellation_token_dispose`.
+SWIFTSCAN_PUBLIC void swiftscan_cache_replay_compilation_async(
+    swiftscan_cas_t cas, swiftscan_cache_replay_instance_t,
+    swiftscan_cached_compilation_t, void *ctx,
+    void (*callback)(void *ctx, swiftscan_cache_result_t,
+                     swiftscan_string_ref_t std_out,
+                     swiftscan_string_ref_t std_err,
+                     swiftscan_string_ref_t error),
+    swiftscan_cache_cancellation_token_t *);
+
 //===----------------------------------------------------------------------===//
 
 SWIFTSCAN_END_DECLS