CMake获取源文件属性命令get_source_file_pr

可以使用get_source_file_property命令获取指定源文件的属性，源文件属性默认是从当前目录属性中获取。

命令格式

get_source_file_property(<variable> <file>
[DIRECTORY <dir> | TARGET_DIRECTORY <target>]
<property>)

• <variable>：必选参数，源文件属性的存储结果
• <file>：必选参数，源文件名称
• DIRECTORY <dir>：可选参数，从指定的<dir>目录获取属性，前提是该目录是已经通过add_subdirectory()添加或者是CMake构建的顶层目录。如果是相对路径，则是针对当前目录的相对路径。
• TARGET_DIRECTORY <target>：可选参数，从构建目标<target>被创建的目录中获取属性，前提是<target>必须已经存在（通过add_executable或add_libraray创建）
• <property>：必选参数，属性名称

简单示例

下面展示获取源文件LOCATION属性的示例，该属性表示源文件的全路径。更多的源文件属性请参考这里。

假设接下来的目录结构为：

get_source_file_property/
├── CMakeLists.txt
├── main.cpp
└── test
    ├── CMakeLists.txt
    └── test.cpp

其中get_source_file_property/test/test.cpp提供了一个test_print()接口，并被编译成test库，供get_source_file_property/main.cpp调用。

get_source_file_property/test/test.cpp文件内容：

#include <iostream>

void test_print()
{
    std::cout << "In test: say hello!" << std::endl;
}

get_source_file_property/main.cpp文件内容：

extern void test_print();

int main(int argc, char** argv)
{
    test_print();
    return 0;
}

• 不指定目录（使用默认目录）

  get_source_file_property/CMakeLists.txt文件内容：

  cmake_minimum_required(VERSION 3.22.1)
  project(test)
  get_source_file_property(file_full_path test.cpp LOCATION)
  message("# Get source file property LOCATION: ${file_full_path}")
  

  get_source_file_property/test/CMakeLists.txt文件内容：

  get_source_file_property(file_full_path test.cpp LOCATION)
  message("# In subdirectory test, Get source file property LOCATION: ${file_full_path}")
  

  运行cmake .，输出如下：

  # In subdirectory test, Get source file property LOCATION: /XXX/get_source_file_property/test/test.cpp
  # Get source file property LOCATION: /XXX/get_source_file_property/test.cpp
  

  说明，即使是相同的文件，在不同的目录下，使用默认的目录就是源文件当前所在的目录。

• 指定目录

  get_source_file_property/CMakeLists.txt文件内容（指定获取test目录）：

  cmake_minimum_required(VERSION 3.22.1)
  project(test)
  add_subdirectory(test)
  get_source_file_property(file_full_path main.cpp LOCATION)
  message("# Get source file property LOCATION: ${file_full_path}")
  get_source_file_property(file_full_path test/test.cpp DIRECTORY test LOCATION)
  message("# Get source file test/test.cpp from directory test property LOCATION: ${file_full_path}")
  

  运行cmake .结果为：

  # In subdirectory test, Get source file property LOCATION: /XXX/get_source_file_property/test/test.cpp
  # Get source file from directory test property LOCATION: /XXX/get_source_file_property/test.cpp
  # Get source file test/test.cpp from directory test property LOCATION: /XXX/get_source_file_property/test/test.cpp
  

• 指定构建目标所在目录

  get_source_file_property/CMakeLists.txt文件内容（指定获取test库所在的目录）：

  cmake_minimum_required(VERSION 3.22.1)
  project(test)
  add_subdirectory(test)
  get_source_file_property(file_full_path main.cpp LOCATION)
  message("# Get source file property LOCATION: ${file_full_path}")
  get_source_file_property(file_full_path test/test.cpp DIRECTORY test LOCATION)
  message("# Get source file test/test.cpp from directory test property LOCATION: ${file_full_path}")
  get_source_file_property(file_full_path test/test.cpp TARGET_DIRECTORY test LOCATION)
  message("# Get source file test/test.cpp from target test property LOCATION: ${file_full_path}")
  

  get_source_file_property/test/CMakeLists.txt文件内容（指定获取test库所在的目录）：

  get_source_file_property(file_full_path test.cpp LOCATION)
  message("# In subdirectory test, Get source file property LOCATION: ${file_full_path}")
  add_library(test test.cpp)
  

  运行cmake .结果为：

  # In subdirectory test, Get source file property LOCATION: /XXX/get_source_file_property/test/test.cpp
  # Get source file from directory test property LOCATION: /XXX/get_source_file_property/test.cpp
  # Get source file test/test.cpp from directory test property LOCATION: /XXX/get_source_file_property/test/test.cpp
  # Get source file test/test.cpp from target test property LOCATION: /XXX/get_source_file_property/test/test.cpp