Share blocking code between Call.c and Variadic.c

ffi · Jun 4, 2016 · a00e9ce · a00e9ce
1 parent 61b7833
commit a00e9ce
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Showing 3 changed files with 53 additions and 25 deletions.
diff --git a/ext/ffi_c/Call.c b/ext/ffi_c/Call.c
@@ -338,40 +338,27 @@ rbffi_SetupCallParams(int argc, VALUE* argv, int paramCount, Type** paramTypes,
     }
 }
 
-
-typedef struct BlockingCall_ {
-    rbffi_frame_t* frame;
-    void* function;
-    FunctionType* info;
-    void **ffiValues;
-    void* retval;
-    void* params;
-#if !(defined(HAVE_RB_THREAD_BLOCKING_REGION) || defined(HAVE_RB_THREAD_CALL_WITHOUT_GVL))
-    void* stkretval;
-#endif
-} BlockingCall;
-
 static VALUE
 call_blocking_function(void* data)
 {
-    BlockingCall* b = (BlockingCall *) data;
+    rbffi_blocking_call_t* b = (rbffi_blocking_call_t *) data;
     b->frame->has_gvl = false;
-    ffi_call(&b->info->ffi_cif, FFI_FN(b->function), b->retval, b->ffiValues);
+    ffi_call(&b->cif, FFI_FN(b->function), b->retval, b->ffiValues);
     b->frame->has_gvl = true;
 
     return Qnil;
 }
 
-static VALUE
-do_blocking_call(void *data)
+VALUE
+rbffi_do_blocking_call(void *data)
 {
     rbffi_thread_blocking_region(call_blocking_function, data, (void *) -1, NULL);
 
     return Qnil;
 }
 
-static VALUE
-save_frame_exception(void *data, VALUE exc)
+VALUE
+rbffi_save_frame_exception(void *data, VALUE exc)
 {
     rbffi_frame_t* frame = (rbffi_frame_t *) data;
     frame->exc = exc;
@@ -390,7 +377,7 @@ rbffi_CallFunction(int argc, VALUE* argv, void* function, FunctionType* fnInfo)
     retval = alloca(MAX(fnInfo->ffi_cif.rtype->size, FFI_SIZEOF_ARG));
 
     if (unlikely(fnInfo->blocking)) {
-        BlockingCall* bc;
+        rbffi_blocking_call_t* bc;
 
         /*
          * due to the way thread switching works on older ruby variants, we
@@ -399,16 +386,16 @@ rbffi_CallFunction(int argc, VALUE* argv, void* function, FunctionType* fnInfo)
 #if defined(HAVE_RB_THREAD_BLOCKING_REGION) || defined(HAVE_RB_THREAD_CALL_WITHOUT_GVL)
         ffiValues = ALLOCA_N(void *, fnInfo->parameterCount);
         params = ALLOCA_N(FFIStorage, fnInfo->parameterCount);
-        bc = ALLOCA_N(BlockingCall, 1);
+        bc = ALLOCA_N(rbffi_blocking_call_t, 1);
         bc->retval = retval;
 #else
         ffiValues = ALLOC_N(void *, fnInfo->parameterCount);
         params = ALLOC_N(FFIStorage, fnInfo->parameterCount);
-        bc = ALLOC_N(BlockingCall, 1);
+        bc = ALLOC_N(rbffi_blocking_call_t, 1);
         bc->retval = xmalloc(MAX(fnInfo->ffi_cif.rtype->size, FFI_SIZEOF_ARG));
         bc->stkretval = retval;
 #endif
-        bc->info = fnInfo;
+        bc->cif = fnInfo->ffi_cif;
         bc->function = function;
         bc->ffiValues = ffiValues;
         bc->params = params;
@@ -419,11 +406,11 @@ rbffi_CallFunction(int argc, VALUE* argv, void* function, FunctionType* fnInfo)
             fnInfo->callbackParameters, fnInfo->callbackCount, fnInfo->rbEnums);
 
         rbffi_frame_push(&frame); 
-        rb_rescue2(do_blocking_call, (VALUE) bc, save_frame_exception, (VALUE) &frame, rb_eException, (VALUE) 0);
+        rb_rescue2(rbffi_do_blocking_call, (VALUE) bc, rbffi_save_frame_exception, (VALUE) &frame, rb_eException, (VALUE) 0);
         rbffi_frame_pop(&frame);
 
 #if !(defined(HAVE_RB_THREAD_BLOCKING_REGION) || defined(HAVE_RB_THREAD_CALL_WITHOUT_GVL))
-        memcpy(bc->stkretval, bc->retval, MAX(bc->info->ffi_cif.rtype->size, FFI_SIZEOF_ARG));
+        memcpy(bc->stkretval, bc->retval, MAX(bc->cif.rtype->size, FFI_SIZEOF_ARG));
         xfree(bc->params);
         xfree(bc->ffiValues);
         xfree(bc->retval);

diff --git a/ext/ffi_c/Call.h b/ext/ffi_c/Call.h
@@ -33,6 +33,8 @@
 #ifndef RBFFI_CALL_H
 #define	RBFFI_CALL_H
 
+#include "Thread.h"
+
 #ifdef	__cplusplus
 extern "C" {
 #endif
@@ -85,6 +87,21 @@ Invoker rbffi_GetInvoker(struct FunctionType_* fnInfo);
 extern VALUE rbffi_GetEnumValue(VALUE enums, VALUE value);
 extern int rbffi_GetSignedIntValue(VALUE value, int type, int minValue, int maxValue, const char* typeName, VALUE enums);
 
+typedef struct rbffi_blocking_call {
+    rbffi_frame_t* frame;
+    void* function;
+    ffi_cif cif;
+    void **ffiValues;
+    void* retval;
+    void* params;
+#if !(defined(HAVE_RB_THREAD_BLOCKING_REGION) || defined(HAVE_RB_THREAD_CALL_WITHOUT_GVL))
+    void* stkretval;
+#endif
+} rbffi_blocking_call_t;
+
+VALUE rbffi_do_blocking_call(void* data);
+VALUE rbffi_save_frame_exception(void *data, VALUE exc);
+
 #ifdef	__cplusplus
 }
 #endif

diff --git a/ext/ffi_c/Variadic.c b/ext/ffi_c/Variadic.c
@@ -64,6 +64,7 @@ typedef struct VariadicInvoker_ {
     ffi_abi abi;
     void* function;
     int paramCount;
+    bool blocking;
 } VariadicInvoker;
 
 
@@ -84,6 +85,7 @@ variadic_allocate(VALUE klass)
     invoker->rbAddress = Qnil;
     invoker->rbEnums = Qnil;
     invoker->rbReturnType = Qnil;
+    invoker->blocking = false;
 
     return obj;
 }
@@ -115,6 +117,7 @@ variadic_initialize(VALUE self, VALUE rbFunction, VALUE rbParameterTypes, VALUE
     invoker->rbEnums = rb_hash_aref(options, ID2SYM(rb_intern("enums")));
     invoker->rbAddress = rbFunction;
     invoker->function = rbffi_AbstractMemory_Cast(rbFunction, rbffi_PointerClass)->address;
+    invoker->blocking = RTEST(rb_hash_aref(options, ID2SYM(rb_intern("blocking"))));
 
 #if defined(X86_WIN32)
     rbConventionStr = rb_funcall2(convention, rb_intern("to_s"), 0, NULL);
@@ -253,7 +256,28 @@ variadic_invoke(VALUE self, VALUE parameterTypes, VALUE parameterValues)
         ffiValues, NULL, 0, invoker->rbEnums);
 
     rbffi_frame_push(&frame);
+#ifdef HAVE_RB_THREAD_CALL_WITHOUT_GVL
+    /* In Call.c, blocking: true is supported on older ruby variants
+     * without rb_thread_call_without_gvl by allocating on the heap instead
+     * of the stack. Since this functionality is being added later,
+     * we’re skipping support for old rubies here. */
+    if(unlikely(invoker->blocking)) {
+        rbffi_blocking_call_t* bc;
+        bc = ALLOCA_N(rbffi_blocking_call_t, 1);
+        bc->retval = retval;
+        bc->function = invoker->function;
+        bc->ffiValues = ffiValues;
+        bc->params = params;
+        bc->frame = &frame;
+        bc->cif = cif;
+
+        rb_rescue2(rbffi_do_blocking_call, (VALUE) bc, rbffi_save_frame_exception, (VALUE) &frame, rb_eException, (VALUE) 0);
+    } else {
+        ffi_call(&cif, FFI_FN(invoker->function), retval, ffiValues);
+    }
+#else
     ffi_call(&cif, FFI_FN(invoker->function), retval, ffiValues);
+#endif
     rbffi_frame_pop(&frame);
 
     rbffi_save_errno();