[C++] Fix Windows 32 bits compile and runtime failures (#11082)

### Motivation

C++ source code cannot be compiled successfully for Windows 32-bit build. The compile error is:

>  fatal error C1021: invalid preprocessor command 'warning'

It's because `#warning` preprocessor directive is not supported by MSVC compilers.

And even if the related code was remove and the build succeeded, a example producer program would crash. This bug is introduced from #6129. It's because hardware CRC32 implementation on Windows is only provided for 64-bit programs. However, the `__cpuid` check in `crc32_initialize()` still returns true for 32-bit build, so finally it went here:

```c++
uint32_t crc32c(uint32_t init, const void *buf, size_t len, const chunk_config *config) {
    // SSE 4.2 extension for hw implementation are not present
    abort();
}
```

The `abort()` call will terminate the process.

### Modifications

- Use `#pragma message()`  to replace `#warning` if the compiler is MSVC.
- Fallback to software implementation of CRC32 checksum algorithm if the hardware implementation is not supported.
- Add the workflow to build Windows 32-bit C++ library.
- Fix the wrong document about how to build it for Windows 32-bit.

.github/workflows/ci-cpp-build-windows.yaml

@@ -52,6 +52,13 @@ jobs:
             suffix: 'windows-win64'
             generator: 'Visual Studio 16 2019'
             arch: '-A x64'
+          - name: 'Windows x86'
+            os: windows-latest
+            triplet: x86-windows
+            vcpkg_dir: 'C:\vcpkg'
+            suffix: 'windows-win32'
+            generator: 'Visual Studio 16 2019'
+            arch: '-A Win32'
 
     steps:
       - name: checkout

pulsar-client-cpp/README.md

@@ -189,13 +189,13 @@ ${PULSAR_PATH}/pulsar-client-cpp/perf/perfConsumer
 
 It's highly recommended to use `vcpkg` for C++ package management on Windows. It's easy to install and well supported by Visual Studio (2015/2017/2019) and CMake. See [here](https://github.com/microsoft/vcpkg#quick-start-windows) for quick start.
 
-Take 64 bits Windows as an example, you only need to run
+Take Windows 64-bit library as an example, you only need to run
 
 ```bash
 vcpkg install --feature-flags=manifests --triplet x64-windows
 ```
 
-> NOTE: The default triplet is `x86-windows`, see [here](https://github.com/microsoft/vcpkg/blob/master/docs/users/triplets.md) for more details.
+> NOTE: For Windows 32-bit library, change `x64-windows` to `x86-windows`, see [here](https://github.com/microsoft/vcpkg/blob/master/docs/users/triplets.md) for more details about the triplet concept in Vcpkg.
 
 The all dependencies, which are specified by [vcpkg.json](vcpkg.json), will be installed in `vcpkg_installed/` subdirectory,
 
@@ -214,10 +214,8 @@ cmake --build ./build --config Release
 
 Then all artifacts will be built into `build` subdirectory.
 
-> NOTE:
+> NOTE: For Windows 32-bit, you need to use `-A Win32` and `-DVCPKG_TRIPLET=x86-windows`.
 >
-> 1. Change `Release` to `Debug` if you want to build a debug version library.
-> 2. For 32 bits Windows, you need to use `-A Win32` and `-DVCPKG_TRIPLET=x32-windows`.
 
 #### Install dependencies manually
 

pulsar-client-cpp/lib/CMakeLists.txt

@@ -150,7 +150,7 @@ elseif(BUILD_STATIC_LIB)
     # Install regular libpulsar.a
     target_link_libraries(pulsarStatic ${COMMON_LIBS})
     install(TARGETS pulsarStatic DESTINATION lib)
-endif(LINK_STATIC)
+endif()
 
 if (BUILD_STATIC_LIB)
     install(TARGETS pulsarStatic DESTINATION lib)

pulsar-client-cpp/lib/checksum/crc32c_sse42.cc

@@ -19,18 +19,27 @@
 #if BOOST_VERSION >= 105500
 #include <boost/predef.h>
 #else
+#if _MSC_VER
+#pragma message("Boost version is < 1.55, disable CRC32C")
+#else
 #warning "Boost version is < 1.55, disable CRC32C"
 #endif
+#endif
 
 #include <assert.h>
 #include <stdlib.h>
+#include "lib/checksum/crc32c_sw.h"
 
 #if BOOST_ARCH_X86_64
 #include <nmmintrin.h>  // SSE4.2
 #include <wmmintrin.h>  // PCLMUL
 #else
+#ifdef _MSC_VER
+#pragma message("BOOST_ARCH_X86_64 is not defined, CRC32C will be disabled")
+#else
 #warning "BOOST_ARCH_X86_64 is not defined, CRC32C will be disabled"
 #endif
+#endif
 
 #ifdef _MSC_VER
 #include <intrin.h>
@@ -82,6 +91,7 @@ bool crc32c_initialize() {
         DEBUG_PRINTF1("has_pclmulqdq = %d\n", has_pclmulqdq);
         initialized = true;
     }
+
     return has_sse42;
 }
 
@@ -251,7 +261,7 @@ uint32_t crc32c(uint32_t init, const void *buf, size_t len, const chunk_config *
 
 uint32_t crc32c(uint32_t init, const void *buf, size_t len, const chunk_config *config) {
     // SSE 4.2 extension for hw implementation are not present
-    abort();
+    return crc32c_sw(init, buf, len);  // fallback to the software implementation
 }
 
 #endif