#!/bin/bash
#
# blob-to-object
# Author:  Leandro A. F. Pereira
# Version: 1.0
#
# Converts a binary blob to a ELF object; useful to include data inside
# programs (and not require external files).
#
# Usage: blob-to-object filename.ext
#
# The script will then create a header file (filename_ext.h) and a object
# file (filename_ext.o). The binary blob will have filename_ext as its
# name, and the header file will include the file size on its extern
# declaration -- so sizeof(filename_ext) will give the blob size.
#
# Additionally, the script also appends a NUL character after the blob, so
# functions that expects a C-style string will work.
#
# Script based on comment by Zack Weinberg at:
# http://www.burtonini.com/blog/computers/ld-blobs-2007-07-13-15-50
#
#

INPUT=$1

if [ "x$INPUT" == "x" ]; then
       echo "Usage: $0 filename"
       exit 1
fi

INPUT_ID=$(echo $INPUT | sed 's/[\.\-]/_/g')
OUTPUT_OBJ=${INPUT_ID}.o
OUTPUT_HDR=${INPUT_ID}.h
TEMP=$(mktemp embedXXXXXXXXX)
TEMP_S=${TEMP}.s
SIZE=$(wc -c ${INPUT}|cut -d" " -f1)

cat << EOF > $TEMP_S
       .section ".rodata"
       .globl ${INPUT_ID}
       .type ${INPUT_ID}, @object
${INPUT_ID}:
       .incbin "${INPUT}"
       .byte 0
       .size ${INPUT_ID},.-${INPUT_ID}
EOF

cat << EOF > $OUTPUT_HDR
#ifndef __${INPUT_ID}_h__
#define __${INPUT_ID}_h__

extern char ${INPUT_ID}[${SIZE}];

#endif /* __${INPUT_ID}_h__ */
EOF

as $TEMP_S -o $OUTPUT_OBJ
rm -f $TEMP $TEMP_S