core: refactor how libuv companion objects are allocated

All native bindings are allocated and attached to the JS object in an opaque. When what we attach is a native binding to a libuv handle there is a tricky situation: uv_close() is not synchronous, which means that we need to delay freeing the native object until the close callback was called. This is a problem when objects are freed as part of freeing the JS engine, since by the time the close callback is called the JS context and runtime have been freed. In order to avoid this problem, allocate the memory for these "companion" objects with the tjs__ family of functions, which don't depend on the JS context. This also allows us to refactor TJSFreeRuntime to a much more obvious flow. There is no need to walk and close all libuv handles, since they'll all be closed when the JS engine is terminated.
saghul · Jun 20, 2024 · 8daf2b8 · 8daf2b8
1 parent 07b1873
commit 8daf2b8
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Showing 10 changed files with 62 additions and 81 deletions.
diff --git a/src/curl-utils.c b/src/curl-utils.c
@@ -24,6 +24,7 @@
 
 #include "curl-utils.h"
 
+#include "mem.h"
 #include "utils.h"
 #include "version.h"
 
@@ -150,7 +151,7 @@ typedef struct {
 static void uv__poll_close_cb(uv_handle_t *handle) {
     tjs_curl_poll_ctx_t *poll_ctx = handle->data;
     CHECK_NOT_NULL(poll_ctx);
-    free(poll_ctx);
+    tjs__free(poll_ctx);
 }
 
 static void uv__poll_cb(uv_poll_t *handle, int status, int events) {
@@ -182,7 +183,7 @@ static int curl__handle_socket(CURL *easy, curl_socket_t s, int action, void *us
             tjs_curl_poll_ctx_t *poll_ctx;
             if (!socketp) {
                 // Initialize poll handle.
-                poll_ctx = malloc(sizeof(*poll_ctx));
+                poll_ctx = tjs__malloc(sizeof(*poll_ctx));
                 if (!poll_ctx)
                     return -1;
                 CHECK_EQ(uv_poll_init_socket(&qrt->loop, &poll_ctx->poll, s), 0);

diff --git a/src/fswatch.c b/src/fswatch.c
@@ -22,12 +22,12 @@
  * THE SOFTWARE.
  */
 
+#include "mem.h"
 #include "private.h"
 #include "utils.h"
 
 typedef struct {
     JSContext *ctx;
-    JSRuntime *rt;
     uv_fs_event_t handle;
     JSValue callback;
     int closed;
@@ -45,7 +45,7 @@ static void uv__fsevent_close_cb(uv_handle_t *handle) {
     if (fw) {
         fw->closed = 1;
         if (fw->finalized)
-            js_free_rt(fw->rt, fw);
+            tjs__free(fw);
     }
 }
 
@@ -60,7 +60,7 @@ static void tjs_fswatch_finalizer(JSRuntime *rt, JSValue val) {
         JS_FreeValueRT(rt, fw->callback);
         fw->finalized = 1;
         if (fw->closed)
-            js_free_rt(rt, fw);
+            tjs__free(fw);
         else
             maybe_close(fw);
     }
@@ -128,7 +128,7 @@ static void uv__fs_event_cb(uv_fs_event_t *handle, const char *filename, int eve
     if (status != 0)
         return;
 
-    // libuv could set both, if we get rename, ignroe change.
+    // libuv could set both, if we get rename, ignore change.
 
     JSValue event;
     if (events & UV_RENAME) {
@@ -168,33 +168,32 @@ static JSValue tjs_fs_watch(JSContext *ctx, JSValue this_val, int argc, JSValue
         return JS_EXCEPTION;
     }
 
-    TJSFsWatch *fw = js_mallocz(ctx, sizeof(*fw));
+    TJSFsWatch *fw = tjs__mallocz(sizeof(*fw));
     if (!fw) {
         JS_FreeCString(ctx, path);
         JS_FreeValue(ctx, obj);
-        return JS_EXCEPTION;
+        return JS_ThrowOutOfMemory(ctx);
     }
 
     int r = uv_fs_event_init(tjs_get_loop(ctx), &fw->handle);
     if (r != 0) {
         JS_FreeCString(ctx, path);
         JS_FreeValue(ctx, obj);
-        js_free(ctx, fw);
+        tjs__free(fw);
         return JS_ThrowInternalError(ctx, "couldn't initialize handle");
     }
 
     r = uv_fs_event_start(&fw->handle, uv__fs_event_cb, path, UV_FS_EVENT_RECURSIVE);
     if (r != 0) {
         JS_FreeCString(ctx, path);
         JS_FreeValue(ctx, obj);
-        js_free(ctx, fw);
+        tjs__free(fw);
         return tjs_throw_errno(ctx, r);
     }
 
     JS_FreeCString(ctx, path);
 
     fw->ctx = ctx;
-    fw->rt = JS_GetRuntime(ctx);
     fw->handle.data = fw;
     fw->callback = JS_DupValue(ctx, argv[1]);
 

diff --git a/src/mem.c b/src/mem.c
@@ -48,6 +48,14 @@ void *tjs__malloc(size_t size) {
 #endif
 }
 
+void *tjs__mallocz(size_t size) {
+#ifdef TJS__HAS_MIMALLOC
+    return mi_calloc(1, size);
+#else
+    return calloc(1, size);
+#endif
+}
+
 void *tjs__calloc(size_t count, size_t size) {
 #ifdef TJS__HAS_MIMALLOC
     return mi_calloc(count, size);

diff --git a/src/mem.h b/src/mem.h
@@ -29,6 +29,7 @@
 
 size_t tjs__malloc_usable_size(const void *ptr);
 void *tjs__malloc(size_t size);
+void *tjs__mallocz(size_t size);
 void *tjs__calloc(size_t count, size_t size);
 void tjs__free(void *ptr);
 void *tjs__realloc(void *ptr, size_t size);

diff --git a/src/process.c b/src/process.c
@@ -22,6 +22,7 @@
  * THE SOFTWARE.
  */
 
+#include "mem.h"
 #include "private.h"
 #include "utils.h"
 
@@ -33,7 +34,6 @@ static JSClassID tjs_process_class_id;
 
 typedef struct {
     JSContext *ctx;
-    JSRuntime *rt;
     JSValue obj;
     bool closed;
     bool finalized;
@@ -52,7 +52,7 @@ static void uv__close_cb(uv_handle_t *handle) {
     CHECK_NOT_NULL(p);
     p->closed = true;
     if (p->finalized)
-        js_free_rt(p->rt, p);
+        tjs__free(p);
 }
 
 static void maybe_close(TJSProcess *p) {
@@ -69,7 +69,7 @@ static void tjs_process_finalizer(JSRuntime *rt, JSValue val) {
         JS_FreeValueRT(rt, p->stdio[2]);
         p->finalized = true;
         if (p->closed)
-            js_free_rt(rt, p);
+            tjs__free(p);
         else
             maybe_close(p);
     }
@@ -184,14 +184,13 @@ static JSValue tjs_spawn(JSContext *ctx, JSValue this_val, int argc, JSValue *ar
     if (JS_IsException(obj))
         return obj;
 
-    TJSProcess *p = js_mallocz(ctx, sizeof(*p));
+    TJSProcess *p = tjs__mallocz(sizeof(*p));
     if (!p) {
         JS_FreeValue(ctx, obj);
-        return JS_EXCEPTION;
+        return JS_ThrowOutOfMemory(ctx);
     }
 
     p->ctx = ctx;
-    p->rt = JS_GetRuntime(ctx);
     p->process.data = p;
 
     TJS_ClearPromise(ctx, &p->status.result);
@@ -451,7 +450,7 @@ static JSValue tjs_spawn(JSContext *ctx, JSValue this_val, int argc, JSValue *ar
     JS_FreeValue(ctx, p->stdio[0]);
     JS_FreeValue(ctx, p->stdio[1]);
     JS_FreeValue(ctx, p->stdio[2]);
-    js_free(ctx, p);
+    tjs__free(p);
     JS_FreeValue(ctx, obj);
     ret = JS_EXCEPTION;
 cleanup:

diff --git a/src/signals.c b/src/signals.c
@@ -22,13 +22,13 @@
  * THE SOFTWARE.
  */
 
+#include "mem.h"
 #include "private.h"
 #include "utils.h"
 
 
 typedef struct {
     JSContext *ctx;
-    JSRuntime *rt;
     int closed;
     int finalized;
     uv_signal_t handle;
@@ -44,7 +44,7 @@ static void uv__signal_close_cb(uv_handle_t *handle) {
     if (sh) {
         sh->closed = 1;
         if (sh->finalized)
-            js_free_rt(sh->rt, sh);
+            tjs__free(sh);
     }
 }
 
@@ -59,7 +59,7 @@ static void tjs_signal_handler_finalizer(JSRuntime *rt, JSValue val) {
         JS_FreeValueRT(rt, sh->func);
         sh->finalized = 1;
         if (sh->closed)
-            js_free_rt(rt, sh);
+            tjs__free(sh);
         else
             maybe_close(sh);
     }
@@ -97,29 +97,28 @@ static JSValue tjs_signal(JSContext *ctx, JSValue this_val, int argc, JSValue *a
     if (JS_IsException(obj))
         return obj;
 
-    TJSSignalHandler *sh = js_mallocz(ctx, sizeof(*sh));
+    TJSSignalHandler *sh = tjs__mallocz(sizeof(*sh));
     if (!sh) {
         JS_FreeValue(ctx, obj);
-        return JS_EXCEPTION;
+        return JS_ThrowOutOfMemory(ctx);
     }
 
     int r = uv_signal_init(tjs_get_loop(ctx), &sh->handle);
     if (r != 0) {
         JS_FreeValue(ctx, obj);
-        js_free(ctx, sh);
+        tjs__free(sh);
         return JS_ThrowInternalError(ctx, "couldn't initialize Signal handle");
     }
 
     r = uv_signal_start(&sh->handle, uv__signal_cb, sig_num);
     if (r != 0) {
         JS_FreeValue(ctx, obj);
-        js_free(ctx, sh);
+        tjs__free(sh);
         return tjs_throw_errno(ctx, r);
     }
     uv_unref((uv_handle_t *) &sh->handle);
 
     sh->ctx = ctx;
-    sh->rt = JS_GetRuntime(ctx);
     sh->sig_num = sig_num;
     sh->handle.data = sh;
     sh->func = JS_DupValue(ctx, func);

diff --git a/src/streams.c b/src/streams.c
@@ -22,6 +22,7 @@
  * THE SOFTWARE.
  */
 
+#include "mem.h"
 #include "private.h"
 #include "utils.h"
 
@@ -36,7 +37,6 @@ static JSValue tjs_new_tcp(JSContext *ctx, int af);
 
 typedef struct {
     JSContext *ctx;
-    JSRuntime *rt;
     int closed;
     int finalized;
     union {
@@ -83,7 +83,7 @@ static void uv__stream_close_cb(uv_handle_t *handle) {
     CHECK_NOT_NULL(s);
     s->closed = 1;
     if (s->finalized)
-        js_free_rt(s->rt, s);
+        tjs__free(s);
 }
 
 static void maybe_close(TJSStream *s) {
@@ -400,12 +400,7 @@ static JSValue tjs_stream_set_blocking(JSContext *ctx, TJSStream *s, int argc, J
 
 static JSValue tjs_init_stream(JSContext *ctx, JSValue obj, TJSStream *s) {
     s->ctx = ctx;
-    s->rt = JS_GetRuntime(ctx);
-    s->closed = 0;
-    s->finalized = 0;
-
     s->h.handle.data = s;
-
     s->read.b.tarray = JS_UNDEFINED;
     s->read.b.data = NULL;
     s->read.b.len = 0;
@@ -468,16 +463,16 @@ static JSValue tjs_new_tcp(JSContext *ctx, int af) {
     if (JS_IsException(obj))
         return obj;
 
-    s = js_mallocz(ctx, sizeof(*s));
+    s = tjs__mallocz(sizeof(*s));
     if (!s) {
         JS_FreeValue(ctx, obj);
-        return JS_EXCEPTION;
+        return JS_ThrowOutOfMemory(ctx);
     }
 
     r = uv_tcp_init_ex(tjs_get_loop(ctx), &s->h.tcp, af);
     if (r != 0) {
         JS_FreeValue(ctx, obj);
-        js_free(ctx, s);
+        tjs__free(s);
         return JS_ThrowInternalError(ctx, "couldn't initialize TCP handle");
     }
 
@@ -651,16 +646,16 @@ static JSValue tjs_tty_constructor(JSContext *ctx, JSValue new_target, int argc,
     if (JS_IsException(obj))
         return obj;
 
-    s = js_mallocz(ctx, sizeof(*s));
+    s = tjs__mallocz(sizeof(*s));
     if (!s) {
         JS_FreeValue(ctx, obj);
-        return JS_EXCEPTION;
+        return JS_ThrowOutOfMemory(ctx);
     }
 
     r = uv_tty_init(tjs_get_loop(ctx), &s->h.tty, fd, readable);
     if (r != 0) {
         JS_FreeValue(ctx, obj);
-        js_free(ctx, s);
+        tjs__free(s);
         return JS_ThrowInternalError(ctx, "couldn't initialize TTY handle");
     }
 
@@ -733,16 +728,16 @@ JSValue tjs_new_pipe(JSContext *ctx) {
     if (JS_IsException(obj))
         return obj;
 
-    s = js_mallocz(ctx, sizeof(*s));
+    s = tjs__mallocz(sizeof(*s));
     if (!s) {
         JS_FreeValue(ctx, obj);
-        return JS_EXCEPTION;
+        return JS_ThrowOutOfMemory(ctx);
     }
 
     r = uv_pipe_init(tjs_get_loop(ctx), &s->h.pipe, 0);
     if (r != 0) {
         JS_FreeValue(ctx, obj);
-        js_free(ctx, s);
+        tjs__free(s);
         return JS_ThrowInternalError(ctx, "couldn't initialize Pipe handle");
     }