Allow raise to work in standalone mode. NFC (#18283)

Author: sbc100

system/lib/standalone/standalone.c

@@ -5,8 +5,10 @@
  * found in the LICENSE file.
  */
 
+#define _GNU_SOURCE
 #include <assert.h>
 #include <errno.h>
+#include <signal.h>
 #include <stdlib.h>
 #include <string.h>
 #include <sys/mman.h>
@@ -219,3 +221,10 @@ static void wasi_writeln(__wasi_fd_t fd, char* buffer) {
 void _emscripten_out(char* text) { wasi_writeln(1, text); }
 
 void _emscripten_err(char* text) { wasi_writeln(2, text); }
+
+// In the non-standalone build we define this helper function in JS to avoid
+// signture mismatch issues.
+// See: https://github.com/emscripten-core/posixtestsuite/issues/6
+void __call_sighandler(sighandler_t handler, int sig) {
+  handler(sig);
+}

test/other/test_standalone_syscalls.cpp

@@ -2,6 +2,7 @@
 #include <emscripten.h>
 #include <emscripten/html5.h>
 #include <fcntl.h>
+#include <signal.h>
 #include <sys/ioctl.h>
 #include <sys/stat.h>
 #include <sys/types.h>
@@ -15,20 +16,30 @@ int main() {
   assert(fd_out == 1);
   int fd_err = open("/dev/stderr", 0);
   assert(fd_err == 2);
+
   // ioctl and fcntl fail
   int i = ioctl(1, 0);
   assert(i < 0);
   int f = fcntl(1, 0);
   assert(f < 0);
+
   // write to standard streams works.
   write(1, "hello, world!", 5);
   write(1, "\n", 1);
+
   // emscripten_log API works
   emscripten_console_log("log");
   // warnings/errors go to stderr
   emscripten_console_warn("warn");
   emscripten_console_error("error");
   emscripten_console_log("log2");
+
   // check we can call this, but the test doesn't check the output
   emscripten_get_now();
+
+  // This doesn't do anything because we have not handler registered, but it
+  // verifies that `raise` can be included in the build without any non-standard
+  // imports being generated.
+  raise(SIGUSR1);
+  return 0;
 }

test/test_other.py

@@ -7850,12 +7850,12 @@ def run(args, expected):
   def test_wasm_target_and_STANDALONE_WASM(self):
     # STANDALONE_WASM means we never minify imports and exports.
     for opts, potentially_expect_minified_exports_and_imports in (
-      ([],                               False),
+      ([],                           False),
       (['-sSTANDALONE_WASM'],        False),
-      (['-O2'],                          False),
-      (['-O3'],                          True),
+      (['-O2'],                      False),
+      (['-O3'],                      True),
       (['-O3', '-sSTANDALONE_WASM'], False),
-      (['-Os'],                          True),
+      (['-Os'],                      True),
     ):
       # targeting .wasm (without .js) means we enable STANDALONE_WASM automatically, and don't minify imports/exports
       for target in ('out.js', 'out.wasm'):
@@ -7877,11 +7877,11 @@ def test_wasm_target_and_STANDALONE_WASM(self):
         print('  exports', exports)
         print('  imports', imports)
         if expect_minified_exports_and_imports:
-          assert 'a' in exports_and_imports
+          self.assertContained('a', exports_and_imports)
         else:
-          assert 'a' not in exports_and_imports
+          self.assertNotContained('a', exports_and_imports)
         if standalone:
-          assert 'fd_write' in exports_and_imports, 'standalone mode preserves import names for WASI APIs'
+          self.assertContained('fd_write', exports_and_imports, 'standalone mode preserves import names for WASI APIs')
         # verify the wasm runs with the JS
         if target.endswith('.js'):
           self.assertContained('hello, world!', self.run_js('out.js'))