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#!/run/current-system/profile/bin/guile \
-L ./src -e main -s
!#
(use-modules (ice-9 getopt-long)
(ice-9 popen)
(modules lexer lexer)
(modules parser parser)
(modules generator generator)
(modules emitter emitter))
(define version "v0.1")
(define (error message)
(display (string-concatenate `(,message "
Usage:
gscc [OPTIONS] file
Options:
--version, -v: print version information
--debug, -d: turn on verbose output
--lex, -l: run the lexer, but stop before assembly generation
--parse, -p: run the lexer and parser, but stop before assembly generation
--codegen, -c: perform lexing, parsing, and assembly generation, but stop before code emission\n")))
(exit #f))
(define (c-extension? file)
(let ((extension (string-drop file (- (string-length file) 2))))
(string=? extension ".c")))
(define (process file parse? generate? write? dest)
"Driver for lexing, parsing, and assembly generation."
(let* ((port (preprocess file))
(tokens (begin (set-current-input-port port)
(read-tokens))))
(close-input-port port)
(when parse?
(let ((c-ast (p-program tokens)))
(when generate?
(let ((assembly-ast (g-program c-ast)))
(when write?
(let ((program (e-program assembly-ast))
(a-file (string-append dest ".s")))
(when (file-exists? a-file)
(delete-file a-file))
(let ((port (open-output-file a-file)))
(display program port)
(close-port port))
(when (postprocess a-file dest)
(display (string-concatenate `("Postprocess reported success (wrote " ,dest ").\n"))))))))))))
(define (preprocess file)
"Returns an input port containing FILE processed with gcc."
(open-input-pipe (string-append "gcc -E -P " file)))
(define (postprocess src dest)
"Assembles and links SRC, producing executable DEST.
Returns #f on a failure, #t on a success."
(zero? (system (string-concatenate `("gcc " ,src " -o " ,dest)))))
(define (main args)
"Entry point for the gscc. Handles user args and performs initial validity check."
(let* ((option-spec
'((version (single-char #\v) (value #f))
(debug (single-char #\d) (value #f))
(lex (single-char #\l) (value #f))
(parse (single-char #\p) (value #f))
(codegen (single-char #\c) (value #f))))
(options (getopt-long args option-spec))
(rest (option-ref options '() #f))
(file (if (null? rest) #f (car rest))))
(cond
((option-ref options 'version #f)
(display (string-concatenate `("gscc (the 'Guile Scheme C Compiler', " ,version ")\n"))))
((not (equal? 1 (length rest))) (error "Wrong number of arguments."))
((or (not file)
(not (access? file R_OK))
(not (equal? 'regular (stat:type (stat file))))
(not (c-extension? file))) (error "The file could not be read, or it is not a C source code file."))
(#t
(let ((parse? (not (option-ref options 'lex #f)))
(generate? (not (option-ref options 'parse #f)))
(write? (not (option-ref options 'codegen #f))))
(process file
parse?
generate?
write?
(string-drop-right file 2)))))))
;; Local Variables:
;; mode: scheme
;; End:
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