Add modules, open port for reading

5 files changed, 53 insertions, 11 deletions

diff --git a/.dir-locals.el b/.dir-locals.el
new file mode 100644
index 0000000..cb836da
--- /dev/null
+++ b/.dir-locals.el
@@ -0,0 +1,4 @@
+;;; Directory Local Variables            -*- no-byte-compile: t -*-
+;;; For more information see (info "(emacs) Directory Variables")
+
+((scheme-mode . ((compile-command . "guix shell -m manifest.scm -- ./writing-a-c-compiler-tests/test_compiler ./src/gscc --chapter 1 --stage lex"))))
diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..a231d4b
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1 @@
+/writing-a-c-compiler-tests/
diff --git a/manifest.scm b/manifest.scm
new file mode 100644
index 0000000..be6c84e
--- /dev/null
+++ b/manifest.scm
@@ -0,0 +1,5 @@
+(specifications->manifest
+ '(
+   "gcc-toolchain"
+   "python"
+   ))
diff --git a/src/gscc b/src/gscc
index 801bdfe..7ee1bf1 100755
--- a/src/gscc
+++ b/src/gscc
@@ -1,9 +1,10 @@
 #!/run/current-system/profile/bin/guile \
--e main -s
+-L ./src -e main -s
 !#
 
 
-(use-modules (ice-9 getopt-long))
+(use-modules (ice-9 getopt-long)
+	     (modules lexer lexer))
 
 
 (define version "v0.1")
@@ -30,8 +31,11 @@ file on a success."
      (zero? (system (string-concatenate `("gcc -E -P " ,file " -o " ,preprocessed-file-name))))
      preprocessed-file-name)))
 
-(define (process file lex? parse? codegen?)
-  "")
+(define (process file parse? assemble?)
+  "Driver for lexing, parsing, and assembly generation."
+  (let ((port (open-input-file file)))
+    (read-tokens-from-port port)
+    (close-input-port port)))
 
 (define (postprocess file dest)
   "Assembles and links file, producing an executable.
@@ -50,7 +54,7 @@ Returns #f on a failure, #t on a success."
 	 (file (if (null? rest) #f (car rest))))
     (cond
      ((option-ref options 'version #f)
-      (display (string-concatenate `("gscc (the 'Guile Scheme C Compiler', " ,version ")"))))
+      (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))
@@ -58,13 +62,10 @@ Returns #f on a failure, #t on a success."
      (#t
       (let ((source (preprocess file)))
 	(when source
-	  (display (string-concatenate `("Preprocess reported success (wrote " ,source ").")))
+	  (display (string-concatenate `("Preprocess reported success (wrote " ,source ").\n")))
 	  (process source
-		   (option-ref options 'lex #f)
-		   (option-ref options 'parse #f)
-		   (option-ref options 'codegen #f))
-	  (newline)
-	  (display "Done!")))))))
+		   (not (option-ref options 'lex #f))
+		   (not (option-ref options 'parse #f)))))))))
 
 
 ;; Local Variables:
diff --git a/src/modules/lexer/lexer.scm b/src/modules/lexer/lexer.scm
new file mode 100644
index 0000000..0661fa6
--- /dev/null
+++ b/src/modules/lexer/lexer.scm
@@ -0,0 +1,31 @@
+(define-module (modules lexer lexer)
+  #:export (read-tokens-from-port))
+
+(define (read-tokens-from-port port)
+  ""
+  (display (read-char port)))
+
+(define (read-token)
+
+  (define (read-token-loop first-char)
+    (cond
+
+     ((or (char-whitespace? first-char))
+      (read-token)
+
+      ((eq? first-char #\()
+       (cons 'left-paren #\())
+      ((eq? first-char #\))
+       (cons 'right-paren #\)))
+      ((eq? first-char #\{)
+       (cons 'right-bracket #\{))
+      ((eq? first-char #\})
+       (cons 'right-bracket #\}))
+
+      (#t
+       (error "illegal lexical syntax")))))
+
+  (let ((first-char (read-char)))
+    (if (eof-object? first-char)
+        '()
+        (cons (read-token-loop first-char) '()))))