(#6884) Build openssl for emscripten

* Build openssl package for Emscripten. Disable things that are not compatible.

* remove disable things; some algorithms work faster with those options;

* remove unused things

* add validate

* remove unnecessary disabled things

* fix typo

recipes/openssl/1.x.x/conanfile.py

@@ -76,6 +76,8 @@ class OpenSSLConan(ConanFile):
                "no_asm": [True, False],
                "enable_weak_ssl_ciphers": [True, False],
                "386": [True, False],
+               "no_stdio": [True, False],
+               "no_tests": [True, False],
                "no_sse2": [True, False],
                "no_bf": [True, False],
                "no_cast": [True, False],
@@ -172,6 +174,12 @@ def config_options(self):
         else:
             del self.options.fPIC
 
+        if self.settings.os == "Emscripten":
+            self.options.no_asm = True
+            self.options.no_threads = True
+            self.options.no_stdio = True
+            self.options.no_tests = True
+
     def build_requirements(self):
         if tools.os_info.is_windows:
             if not self._win_bash:
@@ -848,6 +856,11 @@ def _module_file_rel_path(self):
         return os.path.join(self._module_subfolder,
                             "conan-official-{}-variables.cmake".format(self.name))
 
+    def validate(self):
+        if self.settings.os == "Emscripten":
+            if not all((self.options.no_asm, self.options.no_threads, self.options.no_stdio, self.options.no_tests)):
+                raise ConanInvalidConfiguration("os=Emscripten requires openssl:{no_asm,no_threads,no_stdio,no_tests}=True")
+
     def package_info(self):
         self.cpp_info.names["cmake_find_package"] = "OpenSSL"
         self.cpp_info.names["cmake_find_package_multi"] = "OpenSSL"