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
