Add auto-generated sigs for the fetch API. NFC

Followup to #19028 which laid the groundwork for auto-generated sigs.

Author: sbc100

src/library_sigs.js

@@ -271,6 +271,9 @@ sigs = {
   _emscripten_dbg__sig: 'vp',
   _emscripten_dlopen_js__sig: 'vpppp',
   _emscripten_err__sig: 'vp',
+  _emscripten_fetch_free__sig: 'vi',
+  _emscripten_fetch_get_response_headers__sig: 'pipp',
+  _emscripten_fetch_get_response_headers_length__sig: 'pi',
   _emscripten_fs_load_embedded_files__sig: 'vp',
   _emscripten_get_now_is_monotonic__sig: 'i',
   _emscripten_get_progname__sig: 'vpi',
@@ -601,6 +604,7 @@ sigs = {
   emscripten_sleep__sig: 'vi',
   emscripten_stack_snapshot__sig: 'p',
   emscripten_stack_unwind_buffer__sig: 'ippi',
+  emscripten_start_fetch__sig: 'vp',
   emscripten_supports_offscreencanvas__sig: 'i',
   emscripten_throw_number__sig: 'vd',
   emscripten_throw_string__sig: 'vp',

src/utility.js

@@ -145,9 +145,7 @@ function mergeInto(obj, other, options = null) {
       if (obj.hasOwnProperty(key)) {
         const oldsig = obj[key];
         const newsig = other[key];
-        if (oldsig != newsig) {
-          error(`Signature redefinition for: ${key}. (old=${oldsig} vs new=${newsig})`);
-        }
+        error(`Signature redefinition for : ${key}. (old=${oldsig} vs new=${newsig})`);
       }
     }
 

system/lib/fetch/emscripten_fetch.c

@@ -17,6 +17,8 @@
 #include <emscripten/threading.h>
 #include <emscripten/console.h>
 
+#include "emscripten_internal.h"
+
 // From https://developer.mozilla.org/en-US/docs/Web/API/XMLHttpRequest/readyState
 #define STATE_UNSENT           0 // Client has been created. open() not called yet.
 #define STATE_OPENED           1 // open() has been called.
@@ -31,12 +33,6 @@
 
 static void fetch_free(emscripten_fetch_t* fetch);
 
-// APIs defined in JS
-void emscripten_start_fetch(emscripten_fetch_t* fetch);
-size_t _emscripten_fetch_get_response_headers_length(int32_t fetchID);
-size_t _emscripten_fetch_get_response_headers(int32_t fetchID, char *dst, size_t dstSizeBytes);
-void _emscripten_fetch_free(unsigned int);
-
 typedef struct emscripten_fetch_queue {
   emscripten_fetch_t** queuedOperations;
   int numQueuedItems;

system/lib/libc/emscripten_internal.h

@@ -107,6 +107,12 @@ void _emscripten_throw_longjmp(void);
 
 void __handle_stack_overflow(void* addr);
 
+// Internal fetch API
+void emscripten_start_fetch(emscripten_fetch_t* fetch);
+size_t _emscripten_fetch_get_response_headers_length(int32_t fetchID);
+size_t _emscripten_fetch_get_response_headers(int32_t fetchID, char *dst, size_t dstSizeBytes);
+void _emscripten_fetch_free(unsigned int);
+
 #ifdef __cplusplus
 }
 #endif

tools/gen_sig_info.py

@@ -37,6 +37,7 @@
 #include <emscripten/html5.h>
 #include <emscripten/fiber.h>
 #include <emscripten/websocket.h>
+#include <emscripten/fetch.h>
 #include <emscripten/webaudio.h>
 #include <wasi/api.h>
 
@@ -228,12 +229,16 @@ def extract_sig_info(sig_info, extra_settings=None, extra_cflags=None):
     'STACK_OVERFLOW_CHECK': 1,
     'FULL_ES3': 1,
     'USE_SDL': 1,
+    'FETCH': 1,
     # Currently GLFW symbols have different sigs for the same symbol because the
     # signatures changed between v2 and v3, so for now we continue to maintain
     # them by hand.
     'USE_GLFW': 0,
-    'JS_LIBRARIES': ['src/library_websocket.js',
-                     'src/library_webaudio.js'],
+    'JS_LIBRARIES': [
+      'src/library_websocket.js',
+      'src/library_webaudio.js',
+      'src/library_fetch.js'
+    ],
     'SUPPORT_LONGJMP': 'emscripten'
   }
   if extra_settings: