mruby: generating readable c code - c
I am beginning with mruby, and I need a little in generating readable .c code using mrbc. I was following this article :
Here it is mentioned :
$ mruby/bin/mrbc -Cinit_tester test_program.rb
will produce test_program.c with some content.
but on my machine when I run this command it says :
mrbc: output file should be specified to compile multiple files
Then I tried
$ mruby/bin/mrbc -Binit_tester test_program.rb
which works , generates c files but its contents are only bytecode:
#include <stdint.h>
const uint8_t init_tester[] = {0x45,0x54,0x49,0x52,0x30,0x30,0x30,0x33,0x73,0x0d,0x00,0x00,0x00,0x65,0x4d,0x41,0x54,0x5a,0x30,0x30,0x30,0x30,0x49,0x52,0x45,0x50,0x00,0x00,0x00,0x47,0x30,0x30,0x30,0x30,0x00,0x00,0x00,0x3f,0x00,0x01,0x00,0x04,0x00,0x00,0x00,0x00,0x00,0x04,0x06,0x00,0x80,0x00,0x3d,0x00,0x00,0x01,0xa0,0x00,0x80,0x00,0x4a,0x00,0x00,0x00,0x00,0x00,0x00,0x01,0x00,0x00,0x0b,0x68,0x65,0x6c,0x6c,0x6f,0x20,0x77,0x6f,0x72,0x6c,0x64,0x00,0x00,0x00,0x01,0x00,0x04,0x70,0x75,0x74,0x73,0x00,0x45,0x4e,0x44,0x00,0x00,0x00,0x00,0x08, };
Which is basically byte code of the mruby code that we have put in c code.
If you look at the blog m under section Readable C Code (.c), this should have actually generated c code.
why is the mrbc not generating readable c code ?
why is the mrbc not generating readable c code?
Well, mrbc is a compiler to generate the binary format of ruby code with RiteVM understands so there is no way of generating a readable C code.
Instead with -v option you can see AST and VM codes of your code
(I prefer to pass -c option too since mrbc will generate *.mrb files without it) .
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So if you want to use this from a C program, you will need to execute it through a function like system or exec. However, since its output is a line of C code, you'd be better off running it from within your build script to create a C script, that you'd then link in to the rest of your program.
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Here's the algorithm:
Open the source code file as text output.
Open the font file as binary input.
Write the array declaration to the output file, something like:
static const unsigned char font[] =
{
While the font file is not empty do:
Read unsigned char from font file, using binary read methods.
Output the unsigned char, in text format, to the source file.
end-while
Write the ending brace and semicolon to the source file.
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