ZOOKEEPER-5095: Add MinGW-w64 cross-compilation support for the ZooKeeper C client

zookeeper-client/zookeeper-client-c/CMakeLists.txt

@@ -23,24 +23,24 @@ set(description "zookeeper C client")
 list(APPEND CMAKE_MODULE_PATH "${CMAKE_SOURCE_DIR}/../../tools/cmake/Modules")
 
 # general options
-if(UNIX)
-  add_compile_options(-Wall -fPIC)
-elseif(WIN32)
+if(MSVC)
   add_compile_options(/W3)
+elseif(MINGW)
+  add_compile_options(-Wall)
+else()
+  add_compile_options(-Wall -fPIC)
 endif()
-add_definitions(-DUSE_STATIC_LIB)
+
+option(BUILD_SHARED_LIBS "Build ZooKeeper client shared libraries" OFF)
+option(BUILD_STATIC_LIBS "Also build ZooKeeper client static libraries" OFF)
 
 # TODO: Enable /WX and /W4 on Windows. Currently there are ~1000 warnings.
 # TODO: Add Solaris support.
-# TODO: Add a shared library option.
 # TODO: Specify symbols to export.
 # TODO: Generate doxygen documentation.
 
 # Sync API option
 option(WANT_SYNCAPI "Enables Sync API support" ON)
-if(WANT_SYNCAPI)
-  add_definitions(-DTHREADED)
-endif()
 
 # CppUnit option
 if(WIN32 OR APPLE)
@@ -130,6 +130,11 @@ endforeach()
 
 # function checks
 include(CheckFunctionExists)
+set(ZOOKEEPER_SAVED_REQUIRED_LIBRARIES ${CMAKE_REQUIRED_LIBRARIES})
+if(WIN32)
+  # Winsock functions cannot be detected unless the probe links ws2_32.
+  list(APPEND CMAKE_REQUIRED_LIBRARIES ws2_32)
+endif()
 set(check_functions
   getcwd
   gethostbyname
@@ -147,10 +152,20 @@ set(check_functions
   strerror
   strtol)
 
+# CheckFunctionExists cannot detect 32-bit stdcall Winsock symbols because it
+# does not include their declarations, so record the known Windows APIs.
+if(WIN32)
+  set(HAVE_GETHOSTBYNAME 1)
+  set(HAVE_GETHOSTNAME 1)
+  set(HAVE_SOCKET 1)
+endif()
+
 foreach(fn ${check_functions})
   to_have(${fn} name)
   check_function_exists(${fn} ${name})
 endforeach()
+set(CMAKE_REQUIRED_LIBRARIES ${ZOOKEEPER_SAVED_REQUIRED_LIBRARIES})
+unset(ZOOKEEPER_SAVED_REQUIRED_LIBRARIES)
 
 # library checks
 set(check_libraries rt m pthread)
@@ -161,7 +176,13 @@ endforeach()
 
 # IPv6 check
 include(CheckStructHasMember)
-check_struct_has_member("struct sockaddr_in6" sin6_addr "netinet/in.h" ZOO_IPV6_ENABLED)
+if(WIN32)
+  check_struct_has_member("struct sockaddr_in6" sin6_addr
+    "winsock2.h;ws2tcpip.h" ZOO_IPV6_ENABLED)
+else()
+  check_struct_has_member("struct sockaddr_in6" sin6_addr
+    "netinet/in.h" ZOO_IPV6_ENABLED)
+endif()
 
 # configure
 configure_file(cmake_config.h.in ${CMAKE_CURRENT_BINARY_DIR}/include/config.h)
@@ -172,46 +193,81 @@ add_library(hashtable STATIC ${hashtable_sources})
 target_include_directories(hashtable PUBLIC include)
 target_link_libraries(hashtable PUBLIC $<$<OR:$<PLATFORM_ID:Linux>,$<PLATFORM_ID:FreeBSD>>:m>)
 
-# zookeeper library
-set(zookeeper_sources
+# ZooKeeper client libraries
+set(zookeeper_common_sources
   src/zookeeper.c
   src/recordio.c
   generated/zookeeper.jute.c
   src/zk_log.c
   src/zk_hashtable.c
   src/addrvec.c)
 
-if(WANT_SYNCAPI)
-  list(APPEND zookeeper_sources src/mt_adaptor.c)
-else()
-  list(APPEND zookeeper_sources src/st_adaptor.c)
-endif()
-
 if(CYRUS_SASL_FOUND)
-  list(APPEND zookeeper_sources src/zk_sasl.c)
+  list(APPEND zookeeper_common_sources src/zk_sasl.c)
 endif()
 
 if(WIN32)
-  list(APPEND zookeeper_sources src/winport.c)
+  list(APPEND zookeeper_common_sources src/winport.c)
 endif()
 
-add_library(zookeeper STATIC ${zookeeper_sources})
-target_include_directories(zookeeper PUBLIC include ${CMAKE_CURRENT_BINARY_DIR}/include generated)
-target_link_libraries(zookeeper PUBLIC
-  hashtable
-  $<$<PLATFORM_ID:Linux>:rt> # clock_gettime
-  $<$<PLATFORM_ID:Windows>:ws2_32>) # Winsock 2.0
+function(add_zookeeper_library target variant library_type adaptor)
+  add_library(${target} ${library_type}
+    ${zookeeper_common_sources} ${adaptor})
+  target_include_directories(${target} PUBLIC
+    include ${CMAKE_CURRENT_BINARY_DIR}/include generated)
+  target_link_libraries(${target} PUBLIC
+    hashtable
+    $<$<PLATFORM_ID:Linux>:rt> # clock_gettime
+    $<$<PLATFORM_ID:Windows>:ws2_32>) # Winsock 2.0
+  set_target_properties(${target} PROPERTIES OUTPUT_NAME zookeeper_${variant})
+
+  if("${library_type}" STREQUAL "SHARED")
+    if(WIN32)
+      # ZOOAPI expands to dllexport while compiling the DLL and dllimport for
+      # consumers. Export the remaining public generated/Jute entry points too.
+      target_compile_definitions(${target} PRIVATE DLL_EXPORT)
+      set_target_properties(${target} PROPERTIES WINDOWS_EXPORT_ALL_SYMBOLS ON)
+    endif()
+  else()
+    target_compile_definitions(${target} PUBLIC USE_STATIC_LIB)
+  endif()
+
+  if("${variant}" STREQUAL "mt")
+    target_compile_definitions(${target} PUBLIC THREADED)
+  endif()
+
+  set(zookeeper_library_targets ${zookeeper_library_targets} ${target} PARENT_SCOPE)
+endfunction()
+
+# Keep the historical CMake default (static only).  Turning on both options
+# produces static and shared artifacts in one build tree.
+set(zookeeper_library_targets)
+if(BUILD_SHARED_LIBS)
+  add_zookeeper_library(zookeeper_st_shared st SHARED src/st_adaptor.c)
+  if(WANT_SYNCAPI)
+    add_zookeeper_library(zookeeper_mt_shared mt SHARED src/mt_adaptor.c)
+  endif()
+endif()
+
+if(NOT BUILD_SHARED_LIBS OR BUILD_STATIC_LIBS)
+  add_zookeeper_library(zookeeper_st_static st STATIC src/st_adaptor.c)
+  if(WANT_SYNCAPI)
+    add_zookeeper_library(zookeeper_mt_static mt STATIC src/mt_adaptor.c)
+  endif()
+endif()
 
 option(WITH_OPENSSL "turn ON/OFF SSL support, or define openssl library location (default: ON)" ON)
 message("-- using WITH_OPENSSL=${WITH_OPENSSL}")
 if(NOT WITH_OPENSSL STREQUAL "OFF")
   if(NOT WITH_OPENSSL STREQUAL "ON")
-    set(OPENSSL_ROOT_DIR,${WITH_OPENSSL})
+    set(OPENSSL_ROOT_DIR ${WITH_OPENSSL})
   endif()
   find_package(OpenSSL)
   if(OPENSSL_FOUND)
-    target_compile_definitions(zookeeper PUBLIC HAVE_OPENSSL_H)
-    target_link_libraries(zookeeper PUBLIC OpenSSL::SSL OpenSSL::Crypto)
+    foreach(target ${zookeeper_library_targets})
+      target_compile_definitions(${target} PUBLIC HAVE_OPENSSL_H)
+      target_link_libraries(${target} PUBLIC OpenSSL::SSL OpenSSL::Crypto)
+    endforeach()
     message("-- OpenSSL libraries found! will build with SSL support.")
   else()
     message("-- WARNING: unable to find OpenSSL libraries! will build without SSL support.")
@@ -220,22 +276,47 @@ endif()
 
 if(WANT_SYNCAPI AND NOT WIN32)
   find_package(Threads REQUIRED)
-  target_link_libraries(zookeeper PUBLIC Threads::Threads)
+  foreach(target zookeeper_mt_shared zookeeper_mt_static)
+    if(TARGET ${target})
+      target_link_libraries(${target} PUBLIC Threads::Threads)
+    endif()
+  endforeach()
 endif()
 
 if(CYRUS_SASL_FOUND)
-  target_compile_definitions(zookeeper PUBLIC HAVE_CYRUS_SASL_H)
-  target_link_libraries(zookeeper PUBLIC CyrusSASL)
+  foreach(target ${zookeeper_library_targets})
+    target_compile_definitions(${target} PUBLIC HAVE_CYRUS_SASL_H)
+    target_link_libraries(${target} PUBLIC CyrusSASL)
+  endforeach()
 endif()
 
-# cli executable
-add_executable(cli src/cli.c)
-target_link_libraries(cli zookeeper)
+# Command-line clients follow the Autotools layout.  When both library kinds
+# are requested, link the samples against the shared libraries.
+if(TARGET zookeeper_st_shared)
+  set(zookeeper_st_cli_target zookeeper_st_shared)
+else()
+  set(zookeeper_st_cli_target zookeeper_st_static)
+endif()
+add_executable(cli_st src/cli.c)
+target_link_libraries(cli_st ${zookeeper_st_cli_target})
+
+# Multithreaded client and load generator are only available with Sync API.
+if(WANT_SYNCAPI)
+  if(TARGET zookeeper_mt_shared)
+    set(zookeeper_mt_cli_target zookeeper_mt_shared)
+  else()
+    set(zookeeper_mt_cli_target zookeeper_mt_static)
+  endif()
+  add_executable(cli_mt src/cli.c)
+  target_link_libraries(cli_mt ${zookeeper_mt_cli_target})
 
-# load_gen executable
-if(WANT_SYNCAPI AND NOT WIN32)
   add_executable(load_gen src/load_gen.c)
-  target_link_libraries(load_gen zookeeper)
+  target_link_libraries(load_gen ${zookeeper_mt_cli_target})
+  if(WIN32)
+    # winport is an internal part of the client DLL, while load_gen uses its
+    # pthread compatibility helpers directly.
+    target_sources(load_gen PRIVATE src/winport.c)
+  endif()
 endif()
 
 # tests
@@ -273,7 +354,11 @@ if(WANT_CPPUNIT)
   target_compile_definitions(zktest
     PRIVATE -DZKSERVER_CMD="${CMAKE_CURRENT_SOURCE_DIR}/tests/zkServer.sh")
   # TODO: Use `find_library()` for `cppunit`.
-  target_link_libraries(zktest zookeeper cppunit dl)
+  if(WANT_SYNCAPI)
+    target_link_libraries(zktest ${zookeeper_mt_cli_target} cppunit dl)
+  else()
+    target_link_libraries(zktest ${zookeeper_st_cli_target} cppunit dl)
+  endif()
 
   # This reads the link flags from the file `tests/wrappers.opt` into
   # the variable `symbol_wrappers` for use in `target_link_libraries`.

zookeeper-client/zookeeper-client-c/README

@@ -39,6 +39,29 @@ Please refer to the "Installation" item under "C Binding" in the
 Programmer's Guide:
    https://zookeeper.apache.org/doc/current/developer/programmers-guide/bindings#installation
 
+MINGW-W64
+
+The CMake build supports both 32-bit and 64-bit MinGW-w64 toolchains. Before
+configuring, run `mvn -pl zookeeper-jute generate-sources -DskipTests` from the
+ZooKeeper top-level directory to generate the Jute C sources. A typical 64-bit
+cross-build from Linux is:
+
+  cmake -S . -B build-mingw64 \
+    -DCMAKE_SYSTEM_NAME=Windows \
+    -DCMAKE_C_COMPILER=x86_64-w64-mingw32-gcc \
+    -DCMAKE_CXX_COMPILER=x86_64-w64-mingw32-g++ \
+    -DBUILD_SHARED_LIBS=ON \
+    -DWITH_OPENSSL=OFF -DWITH_CYRUS_SASL=OFF
+  cmake --build build-mingw64
+
+Use i686-w64-mingw32-gcc and i686-w64-mingw32-g++ for a 32-bit build. OpenSSL
+and Cyrus SASL can be enabled when MinGW-built versions of those dependencies
+are available to CMake. CMake always builds the single-threaded zookeeper_st
+library and, unless `-DWANT_SYNCAPI=OFF` is used, also builds the multithreaded
+zookeeper_mt library. Set `-DBUILD_STATIC_LIBS=ON` alongside
+`-DBUILD_SHARED_LIBS=ON` to produce both static and shared libraries in one
+build directory.
+
 EXAMPLE/SAMPLE C CLIENT SHELL
 
 NOTE: the ZooKeeper C client shell (cli_st and cli_mt) is meant as a

zookeeper-client/zookeeper-client-c/include/win_getopt.h

@@ -77,7 +77,9 @@
 
 #ifndef __GETOPT_H__
 
-#pragma warning(disable:4996);
+#ifdef _MSC_VER
+#pragma warning(disable:4996)
+#endif
 
 #define __GETOPT_H__
 
@@ -136,6 +138,7 @@ static char EMSG[] = "";
 #define	EMSG		""
 #endif
 
+struct option;
 static int getopt_internal(int, char * const *, const char *,
 			   const struct option *, int *, int);
 static int parse_long_options(char * const *, const char *,

zookeeper-client/zookeeper-client-c/include/winconfig.h

@@ -1,14 +1,14 @@
 #ifndef WINCONFIG_H_
 #define WINCONFIG_H_
 
-/* Define to `__inline__' or `__inline' if that's what the C compiler
-   calls it, or to nothing if 'inline' is not supported under any name.  */
+/* GCC-compatible attributes and C99 keywords are supported by MinGW. */
+#ifdef _MSC_VER
 #ifndef __cplusplus
 #define inline __inline
 #endif
-
 #define __attribute__(x)
 #define __func__ __FUNCTION__
+#endif
 
 #define ACL ZKACL /* Conflict with windows API */
 

zookeeper-client/zookeeper-client-c/src/addrvec.h

@@ -25,7 +25,7 @@
 #include <netinet/in.h>
 #include <netdb.h>
 #else
-#include <WinSock2.h>
+#include <winsock2.h>
 #include <stdint.h>
 #endif
 
@@ -135,4 +135,3 @@ int addrvec_eq(const addrvec_t *a1, const addrvec_t *a2);
 #endif // ADDRVEC_H
 
 
-

zookeeper-client/zookeeper-client-c/src/cli.c

@@ -1054,13 +1054,21 @@ int main(int argc, char **argv) {
     FD_ZERO(&wfds);
     FD_ZERO(&efds);
     while (!shutdownThisThing) {
+#ifdef WIN32
+        SOCKET fd;
+#else
         int fd;
+#endif
         int interest;
         int events;
         struct timeval tv;
         int rc;
         zookeeper_interest(zh, &fd, &interest, &tv);
+#ifdef WIN32
+        if (fd != INVALID_SOCKET) {
+#else
         if (fd != -1) {
+#endif
             if (interest&ZOOKEEPER_READ) {
                 FD_SET(fd, &rfds);
             } else {

zookeeper-client/zookeeper-client-c/src/load_gen.c

@@ -19,7 +19,9 @@
 #include <zookeeper.h>
 #include "zookeeper_log.h"
 #include <errno.h>
-#ifdef THREADED 
+#ifdef WIN32
+#include "winport.h"
+#else
 #include <pthread.h>
 #endif
 #include <string.h>
@@ -29,11 +31,11 @@ static zhandle_t *zh;
 
 // *****************************************************************************
 //
-static pthread_cond_t cond=PTHREAD_COND_INITIALIZER;
-static pthread_mutex_t lock=PTHREAD_MUTEX_INITIALIZER;
+static pthread_cond_t cond;
+static pthread_mutex_t lock;
 
-static pthread_cond_t counterCond=PTHREAD_COND_INITIALIZER;
-static pthread_mutex_t counterLock=PTHREAD_MUTEX_INITIALIZER;
+static pthread_cond_t counterCond;
+static pthread_mutex_t counterLock;
 static int counter; 
 
 
@@ -230,6 +232,12 @@ void usage(char *argv[]){
 int main(int argc, char **argv) {
     int nodeCount;
     int cleaning=0;
+
+    pthread_mutex_init(&lock, 0);
+    pthread_cond_init(&cond, 0);
+    pthread_mutex_init(&counterLock, 0);
+    pthread_cond_init(&counterCond, 0);
+
     if (argc < 4) {
         usage(argv);
     }