Modules: optimized memory consumption while streaming in qjs.

This allows to stream long tcp streams or large http response bodies
with low memory consumption.

This works only for qjs engine, because njs has no GC.

This fixes #943 issue on Github.

diff --git a/nginx/ngx_http_js_module.c b/nginx/ngx_http_js_module.c
index 487c8115dcca2fe5b7ba9ba7047eb315abe5a2af..3f38f86f79e3f816982d954c6b9ed9007aa9fd93 100644 (file)
--- a/nginx/ngx_http_js_module.c
+++ b/nginx/ngx_http_js_module.c
@@ -5601,10 +5601,12 @@ static JSValue
 ngx_http_qjs_ext_send_buffer(JSContext *cx, JSValueConst this_val,
     int argc, JSValueConst *argv)
 {
+    size_t               byte_offset, byte_length, len;
     unsigned             last_buf, flush;
-    JSValue              flags, value;
+    JSValue              flags, value, val, buf;
     ngx_str_t            buffer;
     ngx_buf_t           *b;
+    const char          *str;
     ngx_chain_t         *cl;
     ngx_http_js_ctx_t   *ctx;
     ngx_http_request_t  *r;
@@ -5620,10 +5622,6 @@ ngx_http_qjs_ext_send_buffer(JSContext *cx, JSValueConst this_val,
         return JS_ThrowTypeError(cx, "cannot send buffer while not filtering");
     }
 
-    if (ngx_qjs_string(cx, argv[0], &buffer) != NGX_OK) {
-        return JS_ThrowTypeError(cx, "failed get buffer arg");
-    }
-
     flush = ctx->buf->flush;
     last_buf = ctx->buf->last_buf;
 
@@ -5647,29 +5645,106 @@ ngx_http_qjs_ext_send_buffer(JSContext *cx, JSValueConst this_val,
         JS_FreeValue(cx, value);
     }
 
-    cl = ngx_chain_get_free_buf(r->pool, &ctx->free);
-    if (cl == NULL) {
-        return JS_ThrowOutOfMemory(cx);
+    val = argv[0];
+
+    if (JS_IsNullOrUndefined(val)) {
+        buffer.len = 0;
+        buffer.data = NULL;
     }
 
-    b = cl->buf;
+    str = NULL;
+    buf = JS_UNDEFINED;
 
-    b->flush = flush;
-    b->last_buf = last_buf;
+    if (JS_IsString(val)) {
+        goto string;
+    }
 
-    b->memory = (buffer.len ? 1 : 0);
-    b->sync = (buffer.len ? 0 : 1);
-    b->tag = (ngx_buf_tag_t) &ngx_http_js_module;
+    buf = JS_GetTypedArrayBuffer(cx, val, &byte_offset, &byte_length, NULL);
+    if (!JS_IsException(buf)) {
+        buffer.data = JS_GetArrayBuffer(cx, &buffer.len, buf);
+        if (buffer.data == NULL) {
+            JS_FreeValue(cx, buf);
+            return JS_EXCEPTION;
+        }
 
-    b->start = buffer.data;
-    b->end = buffer.data + buffer.len;
-    b->pos = b->start;
-    b->last = b->end;
+        buffer.data += byte_offset;
+        buffer.len = byte_length;
 
-    *ctx->last_out = cl;
-    ctx->last_out = &cl->next;
+    } else {
+string:
+
+        str = JS_ToCStringLen(cx, &buffer.len, val);
+        if (str == NULL) {
+            return JS_EXCEPTION;
+        }
+
+        buffer.data = (u_char *) str;
+    }
+
+    do {
+        cl = ngx_chain_get_free_buf(r->pool, &ctx->free);
+        if (cl == NULL) {
+            goto out_of_memory;
+        }
+
+        b = cl->buf;
+
+        if (b->start == NULL) {
+            b->start = ngx_pnalloc(r->pool, buffer.len);
+            if (b->start == NULL) {
+                goto out_of_memory;
+            }
+
+            len = buffer.len;
+            b->end = b->start + len;
+
+        } else {
+            len = ngx_min(buffer.len, (size_t) (b->end - b->start));
+        }
+
+        memcpy(b->start, buffer.data, len);
+
+        b->pos = b->start;
+        b->last = b->start + len;
+
+        if (buffer.len == len) {
+            b->last_buf = last_buf;
+            b->flush = flush;
+
+        } else {
+            b->last_buf = 0;
+            b->flush = 0;
+        }
+
+        b->memory = (len ? 1 : 0);
+        b->sync = (len ? 0 : 1);
+        b->tag = (ngx_buf_tag_t) &ngx_http_js_module;
+
+        buffer.data += len;
+        buffer.len -= len;
+
+        *ctx->last_out = cl;
+        ctx->last_out = &cl->next;
+
+    } while (buffer.len != 0);
+
+    if (str != NULL) {
+        JS_FreeCString(cx, str);
+    }
+
+    JS_FreeValue(cx, buf);
 
     return JS_UNDEFINED;
+
+out_of_memory:
+
+    if (str != NULL) {
+        JS_FreeCString(cx, str);
+    }
+
+    JS_FreeValue(cx, buf);
+
+    return JS_ThrowOutOfMemory(cx);
 }
 
 

diff --git a/nginx/ngx_stream_js_module.c b/nginx/ngx_stream_js_module.c
index a7446c49b7d684ec3b153e7b3e1e125a2523ead3..13b685e52cc4802eaed98a31c3d070e68e6557a2 100644 (file)
--- a/nginx/ngx_stream_js_module.c
+++ b/nginx/ngx_stream_js_module.c
@@ -2273,10 +2273,12 @@ static JSValue
 ngx_stream_qjs_ext_send(JSContext *cx, JSValueConst this_val, int argc,
     JSValueConst *argv, int from_upstream)
 {
-    JSValue                val;
+    size_t                 byte_offset, byte_length, len;
+    JSValue                val, buf;
     unsigned               last_buf, flush;
     ngx_str_t              buffer;
     ngx_buf_t             *b;
+    const char            *str;
     ngx_chain_t           *cl;
     ngx_connection_t      *c;
     ngx_stream_js_ctx_t   *ctx;
@@ -2295,10 +2297,6 @@ ngx_stream_qjs_ext_send(JSContext *cx, JSValueConst this_val, int argc,
         return JS_ThrowInternalError(cx, "cannot send buffer in this handler");
     }
 
-    if (ngx_qjs_string(cx, argv[0], &buffer) != NGX_OK) {
-        return JS_EXCEPTION;
-    }
-
     /*
      * ctx->buf != NULL when s.send() is called while processing incoming
      * data chunks, otherwise s.send() is called asynchronously
@@ -2353,39 +2351,121 @@ ngx_stream_qjs_ext_send(JSContext *cx, JSValueConst this_val, int argc,
         }
     }
 
-    cl = ngx_chain_get_free_buf(c->pool, &ctx->free);
-    if (cl == NULL) {
-        return JS_ThrowInternalError(cx, "memory error");
+    val = argv[0];
+
+    if (JS_IsNullOrUndefined(val)) {
+        buffer.len = 0;
+        buffer.data = NULL;
     }
 
-    b = cl->buf;
+    str = NULL;
+    buf = JS_UNDEFINED;
 
-    b->flush = flush;
-    b->last_buf = last_buf;
+    if (JS_IsString(val)) {
+        goto string;
+    }
 
-    b->memory = (buffer.len ? 1 : 0);
-    b->sync = (buffer.len ? 0 : 1);
-    b->tag = (ngx_buf_tag_t) &ngx_stream_js_module;
+    buf = JS_GetTypedArrayBuffer(cx, val, &byte_offset, &byte_length, NULL);
+    if (!JS_IsException(buf)) {
+        buffer.data = JS_GetArrayBuffer(cx, &buffer.len, buf);
+        if (buffer.data == NULL) {
+            JS_FreeValue(cx, buf);
+            return JS_EXCEPTION;
+        }
 
-    b->start = buffer.data;
-    b->end = buffer.data + buffer.len;
+        buffer.data += byte_offset;
+        buffer.len = byte_length;
 
-    b->pos = b->start;
-    b->last = b->end;
+    } else {
+string:
 
-    if (from_upstream == NGX_JS_BOOL_UNSET) {
-        *ctx->last_out = cl;
-        ctx->last_out = &cl->next;
+        str = JS_ToCStringLen(cx, &buffer.len, val);
+        if (str == NULL) {
+            return JS_EXCEPTION;
+        }
 
-    } else {
+        buffer.data = (u_char *) str;
+    }
 
-        if (ngx_stream_js_next_filter(s, ctx, cl, from_upstream) == NGX_ERROR) {
-            return JS_ThrowInternalError(cx, "ngx_stream_js_next_filter() "
-                                         "failed");
+    do {
+        cl = ngx_chain_get_free_buf(c->pool, &ctx->free);
+        if (cl == NULL) {
+            goto out_of_memory;
+        }
+
+        b = cl->buf;
+
+        if (b->start == NULL) {
+            b->start = ngx_pnalloc(c->pool, buffer.len);
+            if (b->start == NULL) {
+                goto out_of_memory;
+            }
+
+            len = buffer.len;
+            b->end = b->start + len;
+
+        } else {
+            len = ngx_min(buffer.len, (size_t) (b->end - b->start));
+        }
+
+        memcpy(b->start, buffer.data, len);
+
+        b->pos = b->start;
+        b->last = b->start + len;
+
+        if (buffer.len == len) {
+            b->last_buf = last_buf;
+            b->flush = flush;
+
+        } else {
+            b->last_buf = 0;
+            b->flush = 0;
         }
+
+        b->memory = (len ? 1 : 0);
+        b->sync = (len ? 0 : 1);
+        b->tag = (ngx_buf_tag_t) &ngx_stream_js_module;
+
+        buffer.data += len;
+        buffer.len -= len;
+
+        if (from_upstream == NGX_JS_BOOL_UNSET) {
+            *ctx->last_out = cl;
+            ctx->last_out = &cl->next;
+
+        } else {
+
+            if (ngx_stream_js_next_filter(s, ctx, cl, from_upstream)
+                == NGX_ERROR)
+            {
+                if (str != NULL) {
+                    JS_FreeCString(cx, str);
+                }
+
+                return JS_ThrowInternalError(cx, "ngx_stream_js_next_filter() "
+                                             "failed");
+            }
+        }
+
+    } while (buffer.len != 0);
+
+    if (str != NULL) {
+        JS_FreeCString(cx, str);
     }
 
+    JS_FreeValue(cx, buf);
+
     return JS_UNDEFINED;
+
+out_of_memory:
+
+    if (str != NULL) {
+        JS_FreeCString(cx, str);
+    }
+
+    JS_FreeValue(cx, buf);
+
+    return JS_ThrowInternalError(cx, "memory error");
 }