added emscripten support (#846)

.github/workflows/emscripten.yml

@@ -0,0 +1,60 @@
+name: Emscripten
+
+on: [push, pull_request]
+
+jobs:
+  build-linux:
+    defaults:
+      run:
+        shell: bash
+    name: Emscripten-C++${{matrix.std}}-${{matrix.build_type}}-${{matrix.lib}}-${{matrix.extra}}
+    runs-on: ubuntu-latest
+    container: emscripten/emsdk
+    strategy:
+      fail-fast: true
+      matrix:
+        build_type: [Release, Debug]
+        extra: [no-custom-prefix, custom-prefix]
+        lib: [static]
+        std: [98, 11, 14, 17, 20]
+
+    steps:
+      - uses: actions/checkout@v2
+
+      - name: Setup Dependencies
+        run: |
+          apt-get update
+          DEBIAN_FRONTEND=noninteractive sudo apt-get install -y \
+            cmake \
+            ninja-build
+
+      - name: Setup C++98 Environment
+        if: matrix.std == '98'
+        run: |
+          echo 'CXXFLAGS=-Wno-error=variadic-macros -Wno-error=long-long ${{env.CXXFLAGS}}' >> $GITHUB_ENV
+
+      - name: Configure
+        env:
+          CXXFLAGS: -Wall -Wextra -Wsign-conversion -Wtautological-compare -Wformat-nonliteral -Wundef -Werror -Wno-error=wasm-exception-spec ${{env.CXXFLAGS}}
+        run: |
+          cmake -S . -B build_${{matrix.build_type}} \
+            -DBUILD_SHARED_LIBS=${{matrix.lib == 'shared'}} \
+            -DCMAKE_AR=$(which emar) \
+            -DCMAKE_C_COMPILER=$(which emcc) \
+            -DCMAKE_CXX_COMPILER=$(which em++) \
+            -DCMAKE_CXX_STANDARD=${{matrix.std}} \
+            -DCMAKE_CXX_STANDARD_REQUIRED=ON \
+            -DCMAKE_FIND_ROOT_PATH_MODE_INCLUDE=ONLY \
+            -DCMAKE_FIND_ROOT_PATH_MODE_LIBRARY=ONLY \
+            -DCMAKE_FIND_ROOT_PATH_MODE_PACKAGE=ONLY \
+            -DCMAKE_FIND_ROOT_PATH_MODE_PROGRAM=NEVER \
+            -DCMAKE_INSTALL_PREFIX=${{github.workspace}}/install \
+            -DCMAKE_RANLIB=$(which emranlib) \
+            -DWITH_CUSTOM_PREFIX=${{matrix.extra == 'custom-prefix'}} \
+            -G Ninja \
+            -Werror
+
+      - name: Build
+        run: |
+          cmake --build build_${{matrix.build_type}} \
+                --config ${{matrix.build_type}}

CMakeLists.txt

@@ -93,11 +93,11 @@ find_package (Unwind)
 if (Unwind_FOUND)
   set (HAVE_LIB_UNWIND 1)
 else (Unwind_FOUND)
-  check_include_file_cxx (unwind.h HAVE_UNWIND_H)
   # Check whether linking actually succeeds. ARM toolchains of LLVM unwind
   # implementation do not necessarily provide the _Unwind_Backtrace function
   # which causes the previous check to succeed but the linking to fail.
   check_cxx_symbol_exists (_Unwind_Backtrace unwind.h HAVE__UNWIND_BACKTRACE)
+  check_cxx_symbol_exists (_Unwind_GetIP unwind.h HAVE__UNWIND_GETIP)
 endif (Unwind_FOUND)
 
 check_include_file_cxx (dlfcn.h HAVE_DLFCN_H)
@@ -197,6 +197,7 @@ int main(void)
 }
 " HAVE___SYNC_VAL_COMPARE_AND_SWAP)
 
+if (Threads_FOUND)
   cmake_push_check_state (RESET)
   set (CMAKE_REQUIRED_LIBRARIES Threads::Threads)
   check_cxx_source_compiles ("
@@ -211,6 +212,7 @@ int main(void)
 }
   " HAVE_RWLOCK)
   cmake_pop_check_state ()
+endif (Threads_FOUND)
 
 check_cxx_source_compiles ("
 __declspec(selectany) int a;

src/config.h.cmake.in

@@ -118,12 +118,12 @@
 /* Define to 1 if you have the <unistd.h> header file. */
 #cmakedefine HAVE_UNISTD_H ${HAVE_UNISTD_H}
 
-/* Define if you have the <unwind.h> header file. */
-#cmakedefine HAVE_UNWIND_H
-
 /* Define if you linking to _Unwind_Backtrace is possible. */
 #cmakedefine HAVE__UNWIND_BACKTRACE
 
+/* Define if you linking to _Unwind_GetIP is possible. */
+#cmakedefine HAVE__UNWIND_GETIP
+
 /* define if the compiler supports using expression for operator */
 #cmakedefine HAVE_USING_OPERATOR
 

src/glog/logging.h.in

@@ -97,7 +97,7 @@
 
 @ac_google_start_namespace@
 
-#if @ac_cv_have_uint16_t@      // the C99 format
+#if @ac_cv_have_stdint_h@      // the C99 format
 typedef int32_t int32;
 typedef uint32_t uint32;
 typedef int64_t int64;
@@ -1822,8 +1822,8 @@ GLOG_EXPORT void SetEmailLogging(LogSeverity min_severity,
 
 // A simple function that sends email. dest is a commma-separated
 // list of addressess.  Thread-safe.
-GLOG_EXPORT bool SendEmail(const char *dest,
-                                    const char *subject, const char *body);
+GLOG_EXPORT bool SendEmail(const char* dest, const char* subject,
+                           const char* body);
 
 GLOG_EXPORT const std::vector<std::string>& GetLoggingDirectories();
 

src/glog/platform.h

@@ -50,6 +50,8 @@
 #define GLOG_OS_NETBSD
 #elif defined(__OpenBSD__)
 #define GLOG_OS_OPENBSD
+#elif defined(__EMSCRIPTEN__)
+#define GLOG_OS_EMSCRIPTEN
 #else
 // TODO(hamaji): Add other platforms.
 #error Platform not supported by glog. Please consider to contribute platform information by submitting a pull request on Github.

src/logging.cc

@@ -2188,6 +2188,7 @@ void SetExitOnDFatal(bool value) {
 }  // namespace internal
 }  // namespace base
 
+#ifndef GLOG_OS_EMSCRIPTEN
 // Shell-escaping as we need to shell out ot /bin/mail.
 static const char kDontNeedShellEscapeChars[] =
             "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
@@ -2222,14 +2223,14 @@ static string ShellEscape(const string& src) {
   }
   return result;
 }
-
+#endif
 
 // use_logging controls whether the logging functions LOG/VLOG are used
 // to log errors.  It should be set to false when the caller holds the
 // log_mutex.
 static bool SendEmailInternal(const char*dest, const char *subject,
                               const char*body, bool use_logging) {
-#ifndef __EMSCRIPTEN__
+#ifndef GLOG_OS_EMSCRIPTEN
   if (dest && *dest) {
     if ( use_logging ) {
       VLOG(1) << "Trying to send TITLE:" << subject
@@ -2275,6 +2276,12 @@ static bool SendEmailInternal(const char*dest, const char *subject,
       }
     }
   }
+#else
+  (void)dest;
+  (void)subject;
+  (void)body;
+  (void)use_logging;
+  LOG(WARNING) << "Email support not available; not sending message";
 #endif
   return false;
 }

src/raw_logging.cc

@@ -59,7 +59,8 @@
 # include <unistd.h>
 #endif
 
-#if (defined(HAVE_SYSCALL_H) || defined(HAVE_SYS_SYSCALL_H)) && (!(defined(GLOG_OS_MACOSX)))
+#if (defined(HAVE_SYSCALL_H) || defined(HAVE_SYS_SYSCALL_H)) && \
+    (!(defined(GLOG_OS_MACOSX))) && !defined(GLOG_OS_EMSCRIPTEN)
 #define safe_write(fd, s, len) syscall(SYS_write, fd, s, len)
 #else
 // Not so safe, but what can you do?

src/stacktrace_unwind-inl.h

@@ -73,7 +73,7 @@ static _Unwind_Reason_Code GetOneFrame(struct _Unwind_Context *uc, void *opq) {
   if (targ->skip_count > 0) {
     targ->skip_count--;
   } else {
-    targ->result[targ->count++] = (void *) _Unwind_GetIP(uc);
+    targ->result[targ->count++] = reinterpret_cast<void *>(_Unwind_GetIP(uc));
   }
 
   if (targ->count == targ->max_depth) {

src/symbolize.cc

@@ -834,7 +834,7 @@ static ATTRIBUTE_NOINLINE bool SymbolizeAndDemangle(void *pc, char *out,
 
 _END_GOOGLE_NAMESPACE_
 
-#elif defined(GLOG_OS_MACOSX) && defined(HAVE_DLADDR)
+#elif (defined(GLOG_OS_MACOSX) || defined(GLOG_OS_EMSCRIPTEN)) && defined(HAVE_DLADDR)
 
 #include <dlfcn.h>
 #include <cstring>

src/utilities.h

@@ -88,7 +88,7 @@
 
 #if defined(HAVE_LIB_UNWIND)
 # define STACKTRACE_H "stacktrace_libunwind-inl.h"
-#elif defined(HAVE__UNWIND_BACKTRACE)
+#elif defined(HAVE__UNWIND_BACKTRACE) && defined(HAVE__UNWIND_GETIP)
 # define STACKTRACE_H "stacktrace_unwind-inl.h"
 #elif !defined(NO_FRAME_POINTER)
 # if defined(__i386__) && __GNUC__ >= 2