如何通过 CMake 查找特定/本地文件

我对本地安装的库有疑问。在我的项目中有 xmlrpc++0.7-library：

myproject/
 +-- xmlrpc++0.7/
      +-- src/

如果没有找到，我希望 CMake 使用本地 xmlrpc++0.7 目录进行回退。有两个问题，第一个问题，find_path() 或 find_library() 不适用于本地目录。我使用了一种解决方法来测试 find_xxx() 处理的变量是否为空。如果为空，我手动设置它们。 cmake 生成 Makefile 现在没有错误。但如果我想通过 make 编译项目，c++ 编译器将返回“错误：XmlRpc.h：找不到文件”。文件 XmlRpc.h 位于 myproject/xmlrpc++0.7/src 中，如果我手动编译所有文件，它可以正常工作。

这是我的 CMakeLists.txt。如果有人能指出在上述条件下使用 cmake 的正确解决方案，我将非常高兴。

--- CMakeLists.txt ---

project(webservice_tesseract)
cmake_minimum_required(VERSION 2.6)
set(CMAKE_INCLUDE_CURRENT_DIR ON)

# find tesseract
find_path(TESSERACT_INCLUDE_DIR tesseract/tesseractmain.h
        /opt/local/include
 /usr/local/include
 /usr/include
 )
find_library(TESSERACT_LIBRARY_DIR 
 NAMES tesseract_main
 PATHS 
 /opt/local/lib/
 /usr/local/lib/
 /usr/lib
 )
message(STATUS "looked for tesseract library.")
message(STATUS "Include file detected: [${TESSERACT_INCLUDE_DIR}].")
message(STATUS "Lib file detected: [${TESSERACT_LIBRARY_DIR}].")
add_library(tesseract STATIC IMPORTED)
set_property(TARGET tesseract PROPERTY IMPORTED_LOCATION 
 ${TESSERACT_LIBRARY_DIR}/libtesseractmain.a
 )

#find xmlrpc++
message(STATUS "cmake home dir: [${CMAKE_HOME_DIRECTORY}].")
set(LOCAL_XMLRPCPLUSPLUS ${CMAKE_HOME_DIRECTORY}/xmlrpc0.7++/)
message(STATUS "xmlrpc++ local dir: [${LOCAL_XMLRPCPLUSPLUS}].")
find_path(XMLRPCPLUSPLUS_INCLUDE_DIR XmlRpcServer.h
 ${LOCAL_XMLRPCPLUSPLUS}src
 /opt/local/include
 /usr/local/include
 /usr/include
 )
find_library(XMLRPCPLUSPLUS_LIBRARY_DIR 
 NAMES XmlRpc
 PATHS 
 ${LOCAL_XMLRPCPLUSPLUS}
 /opt/local/lib/
 /usr/local/lib/
 /usr/lib/
 )
# next lines are an ugly workaround because cmake find_xxx() does not find local stuff
if (XMLRPCPLUSPLUS_INCLUDE_DIR)
else (XMLRPCPLUSPLUS_INCLUDE_DIR)
 set(XMLRPCPLUSPLUS_INCLUDE_DIR ${LOCAL_XMLRPCPLUSPLUS}src)
endif (XMLRPCPLUSPLUS_INCLUDE_DIR)
if (XMLRPCPLUSPLUS_LIBRARY_DIR)
else (XMLRPCPLUSPLUS_LIBRARY_DIR)
 set(XMLRPCPLUSPLUS_LIBRARY_DIR ${LOCAL_XMLRPCPLUSPLUS})
endif (XMLRPCPLUSPLUS_LIBRARY_DIR)
message(STATUS "looked for xmlrpc++ library.")
message(STATUS "Include file detected: [${XMLRPCPLUSPLUS_INCLUDE_DIR}].")
message(STATUS "Lib file detected: [${XMLRPCPLUSPLUS_LIBRARY_DIR}].")
add_library(xmlrpc STATIC IMPORTED)
set_property(TARGET xmlrpc PROPERTY IMPORTED_LOCATION 
 ${XMLRPCPLUSPLUS_LIBRARY_DIR}/libXmlRpc.a
 )
#### link together
include_directories(${XMLRPCPLUSPLUS_INCLUDE_DIR} ${TESSERACT_INCLUDE_DIR})
link_directories(${XMLRPCPLUSPLUS_LIBRARY_DIR} ${TESSERACT_LIBRARY_DIR})
add_library(simpleocr STATIC simple_ocr.cpp)
add_executable(webservice_tesseract webservice.cpp)
target_link_libraries(webservice_tesseract xmlrpc tesseract simpleocr)
  

问题已经解决了。这是我的新 CMakeLists.txt：

project(webservice_tesseract)
cmake_minimum_required(VERSION 2.6)
set(CMAKE_INCLUDE_CURRENT_DIR ON)
# find tesseract
find_path(TESSERACT_INCLUDE_DIR tesseract/tesseractmain.h
    /opt/local/include
    /usr/local/include
    /usr/include
    )
find_library(TESSERACT_LIBRARY 
    NAMES tesseract_main
    PATHS 
    /opt/local/lib/
    /usr/local/lib/
    /usr/lib
    )
message(STATUS "looked for tesseract library.")
message(STATUS "Include file detected: [${TESSERACT_INCLUDE_DIR}].")
message(STATUS "Lib file detected: [${TESSERACT_LIBRARY}].")
add_library(tesseract STATIC IMPORTED)
set_property(TARGET tesseract PROPERTY IMPORTED_LOCATION 
    ${TESSERACT_LIBRARY}
    )
#find xmlrpc++
message(STATUS "cmake home dir: [${CMAKE_HOME_DIRECTORY}].")
set(LOCAL_XMLRPCPLUSPLUS ${CMAKE_HOME_DIRECTORY}/xmlrpc++0.7/)
message(STATUS "xmlrpc++ local dir: [${LOCAL_XMLRPCPLUSPLUS}].")
find_path(XMLRPCPLUSPLUS_INCLUDE_DIR XmlRpc.h
    ${LOCAL_XMLRPCPLUSPLUS}src
    /opt/local/include
    /usr/local/include
    /usr/include
    )
find_library(XMLRPCPLUSPLUS_LIBRARY 
    NAMES XmlRpc
    PATHS 
    ${LOCAL_XMLRPCPLUSPLUS}
    /opt/local/lib/
    /usr/local/lib/
    /usr/lib/
    )
message(STATUS "looked for xmlrpc++ library.")
message(STATUS "Include file detected: [${XMLRPCPLUSPLUS_INCLUDE_DIR}].")
message(STATUS "Lib file detected: [${XMLRPCPLUSPLUS_LIBRARY}].")
add_library(xmlrpc STATIC IMPORTED)
set_property(TARGET xmlrpc PROPERTY IMPORTED_LOCATION 
    ${XMLRPCPLUSPLUS_LIBRARY}
    )
#### link together
include_directories(${XMLRPCPLUSPLUS_INCLUDE_DIR} ${TESSERACT_INCLUDE_DIR})
link_directories(${XMLRPCPLUSPLUS_LIBRARY} ${TESSERACT_LIBRARY})
add_library(simpleocr STATIC simple_ocr.cpp)
add_executable(webservice_tesseract webservice.cpp)
target_link_libraries(webservice_tesseract xmlrpc tesseract simpleocr)