feat: replace deprecated http-parser with llhttp (#331)

Node's http-parser (vendored at v2.9.4) is deprecated and frozen. Its
maintained successor is llhttp, which is ~2x faster and keeps the same
incremental, callback-based parsing model.

To avoid pulling Node/npm/llparse into the build, we vendor llhttp's
*pre-generated* C release artifacts (the `release` branch of nodejs/llhttp,
tag release/v9.4.2): include/llhttp.h plus src/{llhttp,api,http}.c. These
compile with the normal C toolchain, so the build toolchain is unchanged.

- thirdparty: drop the http-parser git submodule, vendor llhttp sources,
  and compile the three release .c files into dist/ (see VENDOR.md).
- http_parser_settings: port callbacks to the llhttp_t / llhttp_settings_t
  API (llhttp_settings_init, settings bound at init). The signatures are
  otherwise identical.
- on_headers_complete: http-parser's "return 2" (skip body) maps to llhttp's
  "return 1"; on_message_complete now returns HPE_PAUSED so the parser stops
  cleanly after one message instead of parsing trailing bytes as a pipelined
  request (which would re-enter on_message_begin and trip its asserts). This
  matches http-parser, which returned immediately after firing
  on_message_complete for our requests.
- http_session: llhttp_execute returns an errno rather than a byte count;
  derive bytes-consumed from the buffer length (HPE_OK) or llhttp_get_error_pos
  (HPE_PAUSED / HPE_PAUSED_UPGRADE).
- .vscode: repoint include paths/associations at the new llhttp sources.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: bushidocodes

.gitmodules

@@ -3,9 +3,6 @@
 	url = https://github.com/gwsystems/aWsm
 	ignore = dirty
 	branch = master
-[submodule "http-parser"]
-	path = runtime/thirdparty/http-parser
-	url = https://github.com/gwsystems/http-parser.git
 [submodule "ck"]
 	path = runtime/thirdparty/ck
 	url = https://github.com/gwsystems/ck.git

.vscode/c_cpp_properties.json

@@ -7,7 +7,7 @@
                 "/usr/include/",
                 "${workspaceFolder}/runtime/include/",
                 "${workspaceFolder}/runtime/thirdparty/ck/include/",
-                "${workspaceFolder}/runtime/thirdparty/http-parser/",
+                "${workspaceFolder}/runtime/thirdparty/llhttp/include/",
                 "${workspaceFolder}/runtime/thirdparty/jsmn/",
                 "${workspaceFolder}/awsm/runtime/libc/wasi/include/",
                 "${workspaceFolder}/libsledge/include"

.vscode/settings.json

@@ -66,7 +66,7 @@
 		"http_total.h": "c",
 		"http_request.h": "c",
 		"http.h": "c",
-		"http_parser.h": "c",
+		"llhttp.h": "c",
 		"http_parser_settings.h": "c",
 		"client_socket.h": "c",
 		"context.h": "c",
@@ -205,7 +205,7 @@
 		"**/awsm/target/**": true,
 		"**/runtime/thirdparty/**": true,
 		"**/runtime/thirdparty/ck/**": true,
-		"**/runtime/thirdparty/http-parser/**": true,
+		"**/runtime/thirdparty/llhttp/**": true,
 		"**/runtime/thirdparty/jsmn/**": true,
 		"**/runtime/thirdparty/dist/**": true,
 		"*.o": true,

runtime/Makefile

@@ -127,7 +127,9 @@ INCLUDES += -Iinclude/ -Ithirdparty/dist/include/ -I../libsledge/include/
 CFILES += src/*.c
 CFILES += src/arch/${ARCH}/*.c
 CFILES += src/libc/*.c
-CFILES += thirdparty/dist/lib/http_parser.o
+CFILES += thirdparty/dist/lib/llhttp.o
+CFILES += thirdparty/dist/lib/llhttp_api.o
+CFILES += thirdparty/dist/lib/llhttp_http.o
 
 # Configuring Jasmine
 JSMNCFLAGS += -DJSMN_STATIC
@@ -157,7 +159,9 @@ runtime.clean:
 	@rm -f bin/${BINARY_NAME}
 
 # Thirdparty Dependency Rules
-thirdparty/dist/lib/http_parser.o: thirdparty
+thirdparty/dist/lib/llhttp.o: thirdparty
+thirdparty/dist/lib/llhttp_api.o: thirdparty
+thirdparty/dist/lib/llhttp_http.o: thirdparty
 thirdparty/dist/include/*.h: thirdparty
 
 .PHONY: thirdparty

runtime/include/http_parser_settings.h

@@ -1,12 +1,12 @@
 #pragma once
 
-#include "http_parser.h"
+#include "llhttp.h"
 
-extern http_parser_settings runtime_http_parser_settings;
+extern llhttp_settings_t runtime_http_parser_settings;
 
 void http_parser_settings_initialize(void);
 
-static inline http_parser_settings *
+static inline llhttp_settings_t *
 http_parser_settings_get()
 {
 	return &runtime_http_parser_settings;

runtime/include/http_session.h

@@ -12,7 +12,7 @@
 #include "auto_buf.h"
 #include "debuglog.h"
 #include "epoll_tag.h"
-#include "http_parser.h"
+#include "llhttp.h"
 #include "http_parser_settings.h"
 #include "http_request.h"
 #include "http_route_total.h"
@@ -44,7 +44,7 @@ struct http_session {
 	enum http_session_state state;
 	struct sockaddr         client_address; /* client requesting connection! */
 	int                     socket;
-	struct http_parser      http_parser;
+	llhttp_t                http_parser;
 	struct http_request     http_request;
 	struct auto_buf         request_buffer;
 	struct auto_buf         response_header;
@@ -73,8 +73,9 @@ static inline void
 http_session_parser_init(struct http_session *session)
 {
 	memset(&session->http_request, 0, sizeof(struct http_request));
-	http_parser_init(&session->http_parser, HTTP_REQUEST);
-	/* Set the session as the data the http-parser has access to */
+	/* llhttp binds the callback settings at init time (unlike http-parser, which took them at execute) */
+	llhttp_init(&session->http_parser, HTTP_REQUEST, http_parser_settings_get());
+	/* Set the session as the data the parser has access to */
 	session->http_parser.data = &session->http_request;
 }
 
@@ -293,22 +294,27 @@ http_session_parse(struct http_session *session, ssize_t bytes_received)
 	assert(session != 0);
 	assert(bytes_received > 0);
 
-	const http_parser_settings *settings = http_parser_settings_get();
+	const char *parse_start  = (const char *)&session->request_buffer.data[session->http_request.length_parsed];
+	size_t      parse_length = (size_t)session->request_buffer.size - session->http_request.length_parsed;
 
 #ifdef LOG_HTTP_PARSER
-	debuglog("http_parser_execute(%p, %p, %p, %zu\n)", &session->http_parser, settings,
-	         &session->request_buffer.buffer[session->request_buffer.length], bytes_received);
+	debuglog("llhttp_execute(%p, %p, %zu)\n", &session->http_parser, parse_start, parse_length);
 #endif
-	size_t bytes_parsed =
-	  http_parser_execute(&session->http_parser, settings,
-	                      (const char *)&session->request_buffer.data[session->http_request.length_parsed],
-	                      (size_t)session->request_buffer.size - session->http_request.length_parsed);
-
-	if (session->http_parser.http_errno != HPE_OK) {
-		debuglog("Error: %s, Description: %s\n",
-		         http_errno_name((enum http_errno)session->http_parser.http_errno),
-		         http_errno_description((enum http_errno)session->http_parser.http_errno));
-		debuglog("Length Parsed %zu, Length Read %zu\n", bytes_parsed, (size_t)bytes_received);
+
+	/* Unlike http_parser_execute (which returned a byte count), llhttp_execute returns an error code and
+	 * binds its callback settings at init time. On HPE_OK the whole buffer was consumed. */
+	enum llhttp_errno err = llhttp_execute(&session->http_parser, parse_start, parse_length);
+
+	size_t bytes_parsed;
+	if (likely(err == HPE_OK)) {
+		bytes_parsed = parse_length;
+	} else if (err == HPE_PAUSED || err == HPE_PAUSED_UPGRADE) {
+		/* Parser stopped early (e.g. on an upgrade); count only the bytes it consumed. */
+		bytes_parsed = (size_t)(llhttp_get_error_pos(&session->http_parser) - parse_start);
+	} else {
+		debuglog("Error: %s, Description: %s\n", llhttp_errno_name(err),
+		         llhttp_get_error_reason(&session->http_parser));
+		debuglog("Length Read %zu\n", (size_t)bytes_received);
 		debuglog("Error parsing socket %d\n", session->socket);
 		return -1;
 	}

runtime/src/http_parser_settings.c

@@ -7,7 +7,7 @@
 #include "http_request.h"
 #include "likely.h"
 
-http_parser_settings runtime_http_parser_settings;
+llhttp_settings_t runtime_http_parser_settings;
 
 /***********************************************************************
  * http-parser Callbacks in lifecycle order                            *
@@ -22,7 +22,7 @@ http_parser_settings runtime_http_parser_settings;
  * @returns 0
  */
 int
-http_parser_settings_on_url(http_parser *parser, const char *at, size_t length)
+http_parser_settings_on_url(llhttp_t *parser, const char *at, size_t length)
 {
 	struct http_request *http_request = (struct http_request *)parser->data;
 
@@ -84,7 +84,7 @@ http_parser_settings_on_url(http_parser *parser, const char *at, size_t length)
  * @param parser
  */
 int
-http_parser_settings_on_message_begin(http_parser *parser)
+http_parser_settings_on_message_begin(llhttp_t *parser)
 {
 	struct http_request *http_request = (struct http_request *)parser->data;
 
@@ -111,7 +111,7 @@ http_parser_settings_on_message_begin(http_parser *parser)
  * @returns 0
  */
 int
-http_parser_settings_on_header_field(http_parser *parser, const char *at, size_t length)
+http_parser_settings_on_header_field(llhttp_t *parser, const char *at, size_t length)
 {
 	struct http_request *http_request = (struct http_request *)parser->data;
 
@@ -153,7 +153,7 @@ http_parser_settings_on_header_field(http_parser *parser, const char *at, size_t
  * @returns 0
  */
 int
-http_parser_settings_on_header_value(http_parser *parser, const char *at, size_t length)
+http_parser_settings_on_header_value(llhttp_t *parser, const char *at, size_t length)
 {
 	struct http_request *http_request = (struct http_request *)parser->data;
 
@@ -187,7 +187,7 @@ http_parser_settings_on_header_value(http_parser *parser, const char *at, size_t
  * @param parser
  */
 int
-http_parser_settings_on_header_end(http_parser *parser)
+http_parser_settings_on_header_end(llhttp_t *parser)
 {
 	struct http_request *http_request = (struct http_request *)parser->data;
 
@@ -207,7 +207,9 @@ http_parser_settings_on_header_end(http_parser *parser)
 		return 0;
 	} else {
 		http_request->body_length = 0;
-		return 2;
+		/* Returning 1 tells llhttp to assume no body and proceed straight to
+		 * on_message_complete (http-parser used 2 for the same intent). */
+		return 1;
 	}
 }
 
@@ -223,7 +225,7 @@ const char *http_methods[] = {"OPTIONS", "GET", "HEAD", "POST", "PUT", "DELETE",
  * @returns 0
  */
 int
-http_parser_settings_on_body(http_parser *parser, const char *at, size_t length)
+http_parser_settings_on_body(llhttp_t *parser, const char *at, size_t length)
 {
 	struct http_request *http_request = (struct http_request *)parser->data;
 
@@ -260,7 +262,7 @@ http_parser_settings_on_body(http_parser *parser, const char *at, size_t length)
  * @returns 0
  */
 int
-http_parser_settings_on_msg_end(http_parser *parser)
+http_parser_settings_on_msg_end(llhttp_t *parser)
 {
 	struct http_request *http_request = (struct http_request *)parser->data;
 
@@ -273,7 +275,11 @@ http_parser_settings_on_msg_end(http_parser *parser)
 
 	http_request->message_end = true;
 
-	return 0;
+	/* Pause once a full message is parsed so llhttp stops cleanly instead of trying to parse any trailing
+	 * bytes as a pipelined next message (which would re-enter on_message_begin and trip its asserts). This
+	 * mirrors http-parser, which returned immediately after firing on_message_complete for our requests.
+	 * http_session_parse treats HPE_PAUSED as a normal stop. */
+	return HPE_PAUSED;
 }
 
 /***********************************************************************
@@ -284,7 +290,7 @@ http_parser_settings_on_msg_end(http_parser *parser)
  * The settings global with the Callback Functions for HTTP Events
  */
 static inline void
-http_parser_settings_register_callbacks(http_parser_settings *settings)
+http_parser_settings_register_callbacks(llhttp_settings_t *settings)
 {
 	settings->on_url              = http_parser_settings_on_url;
 	settings->on_message_begin    = http_parser_settings_on_message_begin;
@@ -301,6 +307,6 @@ http_parser_settings_register_callbacks(http_parser_settings *settings)
 void
 http_parser_settings_initialize()
 {
-	http_parser_settings_init(&runtime_http_parser_settings);
+	llhttp_settings_init(&runtime_http_parser_settings);
 	http_parser_settings_register_callbacks(&runtime_http_parser_settings);
 }

runtime/thirdparty/Makefile

@@ -5,7 +5,7 @@ DIST_PREFIX=${CURR_DIR}/dist/
 all: clean build
 
 .PHONY: build
-build: ck jsmn http-parser
+build: ck jsmn llhttp
 
 # Concurrency Kit
 ck/Makefile: ck/Makefile.in ck/configure
@@ -17,20 +17,28 @@ ${DIST_PREFIX}/lib/libck.so: ck/Makefile
 .PHONY: ck
 ck: ${DIST_PREFIX}/lib/libck.so
 
-# HTTP Parser
-${DIST_PREFIX}/include/http_parser.h: http-parser/http_parser.h
-	mkdir -p ${DIST_PREFIX}
+# llhttp HTTP Parser (pre-generated C release of nodejs/llhttp, vendored in llhttp/)
+# We compile the release's three C sources directly so the build needs no Node/npm/llparse toolchain.
+LLHTTP_CFLAGS = -O3 -Illhttp/include
+
+${DIST_PREFIX}/include/llhttp.h: llhttp/include/llhttp.h
 	mkdir -p ${DIST_PREFIX}/include/
-	cp http-parser/http_parser.h ${DIST_PREFIX}/include/
+	cp llhttp/include/llhttp.h ${DIST_PREFIX}/include/
 
-${DIST_PREFIX}/lib/http_parser.o: http-parser/http_parser.c http-parser/http_parser.h
-	mkdir -p ${DIST_PREFIX}
+${DIST_PREFIX}/lib/llhttp.o: llhttp/src/llhttp.c llhttp/include/llhttp.h
+	mkdir -p ${DIST_PREFIX}/lib/
+	$(CC) $(CFLAGS) $(LLHTTP_CFLAGS) -c llhttp/src/llhttp.c -o $@
+
+${DIST_PREFIX}/lib/llhttp_api.o: llhttp/src/api.c llhttp/include/llhttp.h
+	mkdir -p ${DIST_PREFIX}/lib/
+	$(CC) $(CFLAGS) $(LLHTTP_CFLAGS) -c llhttp/src/api.c -o $@
+
+${DIST_PREFIX}/lib/llhttp_http.o: llhttp/src/http.c llhttp/include/llhttp.h
 	mkdir -p ${DIST_PREFIX}/lib/
-	cd http-parser;	$(CC) $(CFLAGS) -I. -c http_parser.c
-	mv http-parser/http_parser.o ${DIST_PREFIX}/lib/
+	$(CC) $(CFLAGS) $(LLHTTP_CFLAGS) -c llhttp/src/http.c -o $@
 
-.PHONY: http-parser
-http-parser: ${DIST_PREFIX}/lib/http_parser.o ${DIST_PREFIX}/include/http_parser.h
+.PHONY: llhttp
+llhttp: ${DIST_PREFIX}/lib/llhttp.o ${DIST_PREFIX}/lib/llhttp_api.o ${DIST_PREFIX}/lib/llhttp_http.o ${DIST_PREFIX}/include/llhttp.h
 
 # Jasmine JSON Parser
 ${DIST_PREFIX}/include/jsmn.h: jsmn/jsmn.h

runtime/thirdparty/http-parser

@@ -0,0 +1,22 @@
+This software is licensed under the MIT License.
+
+Copyright Fedor Indutny, 2018.
+
+Permission is hereby granted, free of charge, to any person obtaining a
+copy of this software and associated documentation files (the
+"Software"), to deal in the Software without restriction, including
+without limitation the rights to use, copy, modify, merge, publish,
+distribute, sublicense, and/or sell copies of the Software, and to permit
+persons to whom the Software is furnished to do so, subject to the
+following conditions:
+
+The above copyright notice and this permission notice shall be included
+in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
+NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
+DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
+OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
+USE OR OTHER DEALINGS IN THE SOFTWARE.