esp-idf/tools/cmake/scripts/data_file_embed_asm.cmake
2018-08-23 11:15:23 +10:00

84 lines
2.6 KiB
CMake

#
# Convert a file (text or binary) into an assembler source file suitable
# for gcc. Designed to replicate 'objcopy' with more predictable
# naming, and supports appending a null byte for embedding text as
# a string.
#
# Designed to be run as a script with "cmake -P"
#
# Set variables DATA_FILE, SOURCE_FILE, FILE_TYPE when running this.
#
# If FILE_TYPE is set to TEXT, a null byte is appended to DATA_FILE's contents
# before SOURCE_FILE is created.
#
# If FILE_TYPE is unset (or any other value), DATA_FILE is copied
# verbatim into SOURCE_FILE.
#
#
if(NOT DATA_FILE)
message(FATAL_ERROR "DATA_FILE for converting must be specified")
endif()
if(NOT SOURCE_FILE)
message(FATAL_ERROR "SOURCE_FILE destination must be specified")
endif()
file(READ "${DATA_FILE}" data HEX)
string(LENGTH "${data}" data_len)
math(EXPR data_len "${data_len} / 2") # 2 hex bytes per byte
if(FILE_TYPE STREQUAL "TEXT")
set(data "${data}00") # null-byte termination
endif()
## Convert string of raw hex bytes to lines of hex bytes as gcc .byte expressions
string(REGEX REPLACE "................................" ".byte \\0\n" data "${data}") # 16 bytes per line
string(REGEX REPLACE "[^\n]+$" ".byte \\0\n" data "${data}") # last line
string(REGEX REPLACE "[0-9a-f][0-9a-f]" "0x\\0, " data "${data}") # hex formatted C bytes
string(REGEX REPLACE ", \n" "\n" data "${data}") # trim the last comma
## Come up with C-friendly symbol name based on source file
get_filename_component(source_filename "${DATA_FILE}" NAME)
string(MAKE_C_IDENTIFIER "${source_filename}" varname)
function(append str)
file(APPEND "${SOURCE_FILE}" "${str}")
endfunction()
function(append_line str)
append("${str}\n")
endfunction()
function(append_identifier symbol)
append_line("\n.global ${symbol}")
append("${symbol}:")
if(${ARGC} GREATER 1) # optional comment
append(" /* ${ARGV1} */")
endif()
append("\n")
endfunction()
file(WRITE "${SOURCE_FILE}" "/*")
append_line(" * Data converted from ${DATA_FILE}")
if(FILE_TYPE STREQUAL "TEXT")
append_line(" * (null byte appended)")
endif()
append_line(" */")
append_line(".data")
append_line(".section .rodata.embedded")
append_identifier("${varname}")
append_identifier("_binary_${varname}_start" "for objcopy compatibility")
append("${data}")
append_identifier("_binary_${varname}_end" "for objcopy compatibility")
append_line("")
if(FILE_TYPE STREQUAL "TEXT")
append_identifier("${varname}_length" "not including null byte")
else()
append_identifier("${varname}_length")
endif()
append_line(".word ${data_len}")