Add multi-compiler support and cross-platform build automation

.clang-format

@@ -0,0 +1,51 @@
+---
+# Generated from piper.cpp and piper.h
+Language: Cpp
+BasedOnStyle: Google
+
+# Basic Indentation
+IndentWidth: 4
+TabWidth: 4
+UseTab: Never
+ContinuationIndentWidth: 4
+
+# Braces (Attached as seen in piper.cpp)
+BreakBeforeBraces: Attach
+AllowShortBlocksOnASingleLine: Never
+AllowShortFunctionsOnASingleLine: Empty
+AllowShortIfStatementsOnASingleLine: Never
+AllowShortLoopsOnASingleLine: false
+
+# Pointer Alignment (Right aligned as per 'piper_synthesizer *synth')
+PointerAlignment: Right
+DerivePointerAlignment: false
+
+# Spacing
+SpaceAfterCStyleCast: false
+SpaceBeforeParens: ControlStatements
+SpaceInEmptyParentheses: false
+SpacesInAngles: false
+SpacesInContainerLiterals: true
+SpacesInCStyleCastParentheses: false
+SpacesInParentheses: false
+SpacesInSquareBrackets: false
+
+# Layout
+ColumnLimit: 80
+BinPackArguments: false
+BinPackParameters: false
+
+# Include Management
+SortIncludes: true
+IncludeBlocks: Regroup
+IncludeCategories:
+  - Regex:           '^<.*\.h>'
+    Priority:        1
+  - Regex:           '^<.*'
+    Priority:        2
+  - Regex:           '.*'
+    Priority:        3
+
+# Ensure access modifiers in structs don't over-indent
+AccessModifierOffset: -4
+...

.gitignore

@@ -20,3 +20,12 @@ src/piper/train/vits/monotonic_align/core.c
 *.so
 
 lightning_logs/
+
+# Application location
+/bin
+
+lib/
+download/
+cmake-build/
+
+/CMakeUserPresets.json

CMakeLists.txt

@@ -1,19 +1,32 @@
+cmake_minimum_required(VERSION 3.26)
 # Builds Python module for Piper using espeak-ng and cmake.
 #
 # This is called automatically by scikit-build from setup.py.
-cmake_minimum_required(VERSION 3.26)
 project(piper LANGUAGES C CXX)
 
+# Get the required variable 'GIT_EXECUTABLE'.
+find_package(Git REQUIRED)
+
+option(BUILD_TESTING "Enable project tests" ON)
+if(BUILD_TESTING)
+    enable_testing()
+endif()
+
 include(ExternalProject)
 
+if (NOT PIPER_BUILD_LIB_ONLY)
 # scikit-build-core will forward Python_* variables
-find_package(Python COMPONENTS Development.Module Development.SABIModule REQUIRED)
+    find_package(Python COMPONENTS Development.Module Development.SABIModule REQUIRED)
+#    include(CMakePrintHelpers)
+#    cmake_print_variables(Python_VERSION Python_INCLUDE_DIRS Python_LIBRARIES)
+endif ()
+
 
 # Install location for espeak-ng
 set(ESPEAKNG_BUILD_DIR ${CMAKE_BINARY_DIR}/espeak_ng)
 set(ESPEAKNG_INSTALL_DIR ${CMAKE_BINARY_DIR}/espeak_ng-install)
 
-if(WIN32)
+if(WIN32 AND MSVC)
     # Special handling for Windows
     set(ESPEAKNG_STATIC_LIB ${ESPEAKNG_INSTALL_DIR}/lib/espeak-ng.lib)
     set(UCD_STATIC_LIB ${ESPEAKNG_BUILD_DIR}/src/espeak_ng_external-build/src/ucd-tools/ucd.lib)
@@ -22,13 +35,25 @@ else()
     set(UCD_STATIC_LIB ${ESPEAKNG_BUILD_DIR}/src/espeak_ng_external-build/src/ucd-tools/libucd.a)
 endif()
 
+# Add the external 'espeak' project and apply the patch to use it as a static library only.
 ExternalProject_Add(espeak_ng_external
     GIT_REPOSITORY https://github.com/espeak-ng/espeak-ng.git
     GIT_TAG 212928b394a96e8fd2096616bfd54e17845c48f6  # 2025-Mar-22
     PREFIX ${ESPEAKNG_BUILD_DIR}
     CMAKE_ARGS
+        -DCMAKE_CROSSCOMPILING:BOOL=${CMAKE_CROSSCOMPILING}
+        # To allow this to work the minimum cmake version is also patched.
+        # By linking the VCRT static libs it will prevent MSVC linker errors in dependent projects.
+        -DCMAKE_MSVC_RUNTIME_LIBRARY=MultiThreaded$<$<CONFIG:Debug>:Debug>
+        # Forward the current toolchain file.
+        -DCMAKE_TOOLCHAIN_FILE=${CMAKE_TOOLCHAIN_FILE}
+        -DCMAKE_SYSTEM_NAME=${CMAKE_SYSTEM_NAME}
         -DCMAKE_INSTALL_PREFIX=${ESPEAKNG_INSTALL_DIR}
         -DBUILD_SHARED_LIBS:BOOL=OFF
+        # Do not compile intonation files when Piper used as a module in another project.
+        -DCOMPILE_INTONATIONS:BOOL=${PROJECT_IS_TOP_LEVEL}
+        # When not disabling tests when not the top level project, the build fails.
+        -DENABLE_TESTS:BOOL=${PROJECT_IS_TOP_LEVEL}
         -DCMAKE_POSITION_INDEPENDENT_CODE:BOOL=ON
         -DUSE_ASYNC:BOOL=OFF
         -DUSE_MBROLA:BOOL=OFF
@@ -45,12 +70,18 @@ ExternalProject_Add(espeak_ng_external
         ${ESPEAKNG_STATIC_LIB}
         ${UCD_STATIC_LIB}
     UPDATE_DISCONNECTED TRUE
+    # Headers are only importing or exporting functions but no consideration when only as a private static library.
+    # Does not make cmake abort when the patch has already been performed by first checking it.
+    PATCH_COMMAND "${GIT_EXECUTABLE}" apply --check --reverse "${CMAKE_CURRENT_LIST_DIR}/libpiper/src/espeak.patch" ||
+        "${GIT_EXECUTABLE}" apply "${CMAKE_CURRENT_LIST_DIR}/libpiper/src/espeak.patch"
 )
 
 include_directories(
     ${ESPEAKNG_INSTALL_DIR}/include
 )
 
+if (NOT PIPER_BUILD_LIB_ONLY)
+
 # espeak bridge
 add_library(espeakbridge MODULE
     src/piper/espeakbridge.c
@@ -86,12 +117,32 @@ install(TARGETS espeakbridge
     RUNTIME DESTINATION .
 )
 
-# Copy espeak-ng-data
-set(DATA_SRC ${CMAKE_BINARY_DIR}/espeak_ng-install/share/espeak-ng-data)
-set(DATA_DST ${CMAKE_CURRENT_SOURCE_DIR}/src/piper/espeak-ng-data)
+endif()
 
-add_custom_target(copy_espeak_ng_data ALL
-    COMMAND ${CMAKE_COMMAND} -E copy_directory ${DATA_SRC} ${DATA_DST}
-    DEPENDS espeak_ng_external
-    COMMENT "Copying espeak-ng-data after espeak-ng external project builds"
-)
+# Projects using this repository as submodule need to deal with 'espeak-ng-data' directory themself.
+if (PROJECT_IS_TOP_LEVEL)
+
+    # Copy espeak-ng-data
+    set(DATA_SRC ${CMAKE_BINARY_DIR}/espeak_ng-install/share/espeak-ng-data)
+    set(DATA_DST ${CMAKE_CURRENT_SOURCE_DIR}/src/piper/espeak-ng-data)
+
+    # The native compiled should have done the copy first.
+    if (NOT CMAKE_CROSSCOMPILING)
+    add_custom_target(copy_espeak_ng_data ALL
+        COMMAND ${CMAKE_COMMAND} -E copy_directory "${DATA_SRC}" "${DATA_DST}"
+        DEPENDS espeak_ng_external
+        COMMENT "Copying espeak-ng-data after espeak-ng external project builds"
+    )
+    else ()
+        if (NOT EXISTS "${DATA_DST}")
+            message(FATAL_ERROR "Compile native first to create directory: ${DATA_DST}")
+        else ()
+            message(VERBOSE "Found required directory: ${DATA_DST}")
+        endif ()
+    endif ()
+
+endif ()
+
+message(STATUS "Compiling from ${CMAKE_HOST_SYSTEM_PROCESSOR} for ${CMAKE_SYSTEM_PROCESSOR}")
+
+add_subdirectory(libpiper)