CMake – Automatically regenerate a file using an external tool and custom target upon “make”
Hi. I'm working on a project and I use cmake for generating "projects", that is, under Linux, a Makefile.
I also use an external tool (re2c) to generate the scanner, and an included tool to generate the parser (lemon, part of sqlite). The problem is I need to "cmake" every time I change something in the grammar (lemon_parser.y) or in the scanner (scanner.re).
The cmake files are:
./CMakeLists.txt:
1 cmake_minimum_required(VERSION 2.6)
2 project(Calc C)
3 #set(CMAKE_USE_RELATIVE_PATHS ON FORCE)
4 set(CMAKE_BUILD_TYPE Debug)
5 #set(CMAKE_VERBOSE_MAKEFILE true)
6 include_directories(${CMAKE_SOURCE_DIR} ${CMAKE_BINARY_DIR}/parser)
7
8 IF ( ${CMAKE_SOURCE_DIR} EQUAL ${CMAKE_BINARY_DIR} AND NOT ${ACCEPT_SOURCE_DIR} )
9 MESSAGE( FATAL "Please choose a different directory for building" )
10 ENDIF( ${CMAKE_SOURCE_DIR} EQUAL ${CMAKE_BINARY_DIR} AND NOT ${ACCEPT_SOURCE_DIR} )
11
12 add_subdirectory(lemon)
13 add_subdirectory(hash)
14 add_subdirectory(parser)
15 #memory safety
16 #add_subdirectory(memory_safety)
17
18 add_executable(calc main.c)
19 target_link_libraries(calc hash parser)
./parser/CMakeLists.txt
and a file irrelevant to the problem:
./hash/CMakeLists.txt:
1 add_library(hash STATIC hash_table.c hash_functions.c)
Software/Hardware used:
Software/Hardware used:
ASKED:
December 5, 2008 11:01 AM
UPDATED:
December 8, 2008 12:09 PM
Answer Wiki:
Fixed it in the meanwhile:
<pre> 1 set(parser_odir "${CMAKE_CURRENT_BINARY_DIR}/")
2 include_directories(${CMAKE_CURRENT_SOURCE_DIR} ${parser_odir})
3
4 #The right way to me would be to use the commands (2) and (4)
5 #but it seems one needs (1) and (3) instead, if regeneration
6 #of the scanner.re and parser.y is desired with only a "make"
7 #command.
8 #
9 #Why I think that would be the right way? Because commands
10 #have output (in cmake terms) and targets don't.
11
12 add_custom_target(lemon_parser
13 COMMAND ${CMAKE_COMMAND} -E copy "lemon_parser.y" "${parser_odir}lemon_parser.y"
14 #(1):
15 COMMAND ${PROJECT_BINARY_DIR}/lemon/lemon d="${CMAKE_CURRENT_SOURCE_DIR}/lempar.c" "${parser_odir}lemon_parser.y"
16 WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}
17 COMMENT "add_custom_target(lemon_parser)"
18 )
19 add_custom_command(OUTPUT "${parser_odir}lemon_parser.c"
20 #(2):
21 # COMMAND ${PROJECT_BINARY_DIR}/lemon/lemon d="${CMAKE_CURRENT_SOURCE_DIR}/lempar.c" "${parser_odir}lemon_parser.y"
22 COMMENT "add_custom_command(parser)"
23 )
24
25 add_custom_target(re2c_scanner
26 #(3):
27 COMMAND re2c -i "${CMAKE_CURRENT_SOURCE_DIR}/scanner.re" > "${parser_odir}scanner.c"
28 COMMENT "add_custom_target(re2c_scanner)"
29 )
30 add_custom_command(OUTPUT "${parser_odir}scanner.c"
31 #(4):
32 # COMMAND re2c -i "${CMAKE_CURRENT_SOURCE_DIR}/scanner.re" > "${parser_odir}scanner.c"
33 COMMENT "add_custom_command(scanner)"
34 )
35 add_library(parser STATIC parser.c ast.c "${parser_odir}scanner.c" "${parser_odir}lemon_parser.c")
36 add_dependencies(parser lemon_parser re2c_scanner)
37 add_dependencies(lemon_parser lemon)</pre>
Hopefully this will help someone else.
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OOps, I’ve forgot to paste the parser/CMakeLists.txt:
1 set(parser_odir "${CMAKE_CURRENT_BINARY_DIR}/") 2 include_directories(${CMAKE_CURRENT_SOURCE_DIR} ${parser_odir}) 3 4 add_custom_command( 5 OUTPUT "${parser_odir}lemon_parser.c" "${parser_odir}lemon_parser.h" "${parser_odir}lemon_parser.out" 6 #COMMAND ${PROJECT_BINARY_DIR}/lemon/lemon d="${CMAKE_CURRENT_SOURCE_DIR}/lempar.c" "${CMAKE_CURRENT_BINARY_DIR}/lemon_parser.y" 7 COMMAND ${PROJECT_BINARY_DIR}/lemon/lemon d="${CMAKE_CURRENT_SOURCE_DIR}/lempar.c" "${parser_odir}lemon_parser.y" 8 DEPENDS lemon "${CMAKE_CURRENT_SOURCE_DIR}/lemon_parser.y" 9 ) 10 #add_custom_target(lemon_parser) 11 file(READ lemon_parser.y parser_content) 12 file(WRITE "${parser_odir}lemon_parser.y" "${parser_content}") 13 14 add_custom_command( 15 OUTPUT "${parser_odir}scanner.c" 16 COMMAND re2c -i "${CMAKE_CURRENT_SOURCE_DIR}/scanner.re" > "${parser_odir}scanner.c" 17 DEPENDS "${parser_odir}lemon_parser.h" "${CMAKE_CURRENT_SOURCE_DIR}/scanner.re" 18 ) 19 #add_custom_target(re2c_scanner) 20 21 #add_custom_target(lemon_parser ALL DEPENDS "${parser_odir}lemon_parser.c" "${parser_odir}lemon_parser.h") 22 add_library(parser STATIC "${parser_odir}lemon_parser.c" "${parser_odir}scanner.c" parser.c ast.c)Is there any feedback area? The small “ask a question” textarea on the right is hard to use.