34 # find PX4 config
35 # look for in tree board config that matches CONFIG input
36 if(NOT PX4_CONFIG_FILE)
37
38 file(GLOB_RECURSE board_configs
39 RELATIVE "${PX4_SOURCE_DIR}/boards"
40 "boards/*.px4board"
41 )
42
43 set(PX4_CONFIGS ${board_configs} CACHE STRING "PX4 board configs" FORCE)
44
45 foreach(filename ${board_configs})
46 # parse input CONFIG into components to match with existing in tree configs
47 # the platform prefix (eg nuttx_) is historical, and removed if present
48 string(REPLACE ".px4board" "" filename_stripped ${filename})
49 string(REPLACE "/" ";" config ${filename_stripped})
50 list(LENGTH config config_len)
51
52 if(${config_len} EQUAL 3)
53 list(GET config 0 vendor)
54 list(GET config 1 model)
55 list(GET config 2 label)
56
57 set(board "${vendor}${model}")
58
59 # <VENDOR>_<MODEL>_<LABEL> (eg px4_fmu-v2_default)
60 # <VENDOR>_<MODEL>_default (eg px4_fmu-v2) # allow skipping label if "default"
61 if ((${CONFIG} MATCHES "${vendor}_${model}_${label}") OR # match full vendor, model, label
62 ¦ ((${label} STREQUAL "default") AND (${CONFIG} STREQUAL "${vendor}_${model}")) # default label can be omitted
63 )
64 set(PX4_CONFIG_FILE "${PX4_SOURCE_DIR}/boards/${filename}" CACHE FILEPATH "path to PX4 CONFIG file" FORCE)
65 set(PX4_BOARD_DIR "${PX4_SOURCE_DIR}/boards/${vendor}/${model}" CACHE STRING "PX4 board directory" FORCE)
66 ¦ ¦ ¦ set(MODEL "${model}" CACHE STRING "PX4 board model" FORCE)
67 ¦ ¦ ¦ set(VENDOR "${vendor}" CACHE STRING "PX4 board vendor" FORCE)
68 ¦ ¦ ¦ set(LABEL "${label}" CACHE STRING "PX4 board vendor" FORCE)
69 break()
70 endif()
71
72 # <BOARD>_<LABEL> (eg px4_fmu-v2_default)
73 # <BOARD>_default (eg px4_fmu-v2) # allow skipping label if "default"
74 if ((${CONFIG} MATCHES "${board}_${label}") OR # match full board, label
75 ¦ ((${label} STREQUAL "default") AND (${CONFIG} STREQUAL "${board}")) # default label can be omitted
76 )
77 set(PX4_CONFIG_FILE "${PX4_SOURCE_DIR}/boards/${filename}" CACHE FILEPATH "path to PX4 CONFIG file" FORCE)
78 set(PX4_BOARD_DIR "${PX4_SOURCE_DIR}/boards/${vendor}/${model}" CACHE STRING "PX4 board directory" FORCE)
79 ¦ ¦ ¦ set(MODEL "${model}" CACHE STRING "PX4 board model" FORCE)
80 ¦ ¦ ¦ set(VENDOR "${vendor}" CACHE STRING "PX4 board vendor" FORCE)
81 ¦ ¦ ¦ set(LABEL "${label}" CACHE STRING "PX4 board vendor" FORCE)
82 break()
83 endif()
84 endif()
85 endforeach()
86 endif()
如注释所说，就是根据调用CMake时传入的参数-DCONFIG=$(1)，找出需要用到的配置，逻辑分析如下：
PS：cmake file相关语法在这。
- 遍历
${PX4_SOURCE_DIR}/boards目录下的文件，过滤条件为"boards/*.px4board"，见后将结果存储在PX4_CONFIGS中以及临时变量${board_configs}中。 - 分析
${board_configs}中的每个文件，以px4/fmu-v2/default.px4board为例：
A.string(REPLACE ".px4board" "" filename_stripped ${filename})去掉文件后缀存储在filename_stripped中，即filename_stripped = px4/fmu-v2/default
B.string(REPLACE "/" ";" config ${filename_stripped})将'/'替换为';'，即config = px4;fmu-v2;default
C.list(LENGTH config config_len)获取config的长度，看来‘；’是一个分割符，即config_len = 3
D. 获取list(GET config 0 vendor)、list(GET config 1 model)、list(GET config 2 label)，即vender = px4 ; model = fmu-v2; label = default
E. 根传入的参数-DCONFIG=$(1)进行比对，如果${CONFIG}能与vender 、model、label匹配上，则找到了正确的配置文件，然后产出几个全局变量保存一些信息，即PX4_CONFIG_FILE PX4_BOARD_DIR MODEL VENDOR LABEL：
64 set(PX4_CONFIG_FILE "${PX4_SOURCE_DIR}/boards/${filename}" CACHE FILEPATH "path to PX4 CONFIG file" FORCE)
65 set(PX4_BOARD_DIR "${PX4_SOURCE_DIR}/boards/${vendor}/${model}" CACHE STRING "PX4 board directory" FORCE)
66 ¦ ¦ ¦ set(MODEL "${model}" CACHE STRING "PX4 board model" FORCE)
67 ¦ ¦ ¦ set(VENDOR "${vendor}" CACHE STRING "PX4 board vendor" FORCE)
68 ¦ ¦ ¦ set(LABEL "${label}" CACHE STRING "PX4 board vendor" FORCE)
再往下：
88 if(NOT PX4_CONFIG_FILE)
89 message(FATAL_ERROR "PX4 config file not set, try one of ${PX4_CONFIGS}")
90 endif()
这个就是检查，没有找到配置文件就退出。
message(STATUS "PX4 config file: ${PX4_CONFIG_FILE}")
打印找到的配置文件。
94 include_directories(${PX4_BOARD_DIR}/src)
添加板子的特殊代码，这里就是boards/px4/fmu-v2/src
96 set(PX4_BOARD ${VENDOR}_${MODEL} CACHE STRING "PX4 board" FORCE)
设置全局变量PX4_BOARD = px4_fmu-v2
98 # board name is uppercase with no underscores when used as a define
99 string(TOUPPER ${PX4_BOARD} PX4_BOARD_NAME)
100 string(REPLACE "-" "_" PX4_BOARD_NAME ${PX4_BOARD_NAME})
101 set(PX4_BOARD_NAME ${PX4_BOARD_NAME} CACHE STRING "PX4 board define" FORCE)
设置全局变量PX4_BOARD_NAME = PX4_FMU_V2
103 set(PX4_BOARD_VENDOR ${VENDOR} CACHE STRING "PX4 board vendor" FORCE)
104 set(PX4_BOARD_MODEL ${MODEL} CACHE STRING "PX4 board model" FORCE)
105
106 set(PX4_BOARD_LABEL ${LABEL} CACHE STRING "PX4 board label" FORCE)
设置全局变量PX4_BOARD_VENDOR = px4; PX4_BOARD_MODEL = fmu-v2; PX4_BOARD_LABEL = default
108 set(PX4_CONFIG "${PX4_BOARD_VENDOR}_${PX4_BOARD_MODEL}_${PX4_BOARD_LABEL}" CACHE STRING "PX4 config" FORCE)
设置全局变量PX4_CONFIG = px4_fmu-v2_default
总结：
这个cmake文件就是根据用户输入的 make的参数，确定具体的配置文件，然后定义几个全局变量供后续使用！
