Initial commit

lang/go/src/sum.sld

@@ -0,0 +1,60 @@
+(define-library (zilch lang go sum)
+  (import
+    (scheme base) (scheme write) (scheme read) (scheme file) (scheme process-context) (scheme lazy) (scheme case-lambda)
+    (chicken file)
+    (zilch magic) (zilch file) (zilch zexpr)
+    (zilch nix drv) (zilch nix path) (zilch nixpkgs)
+    (json)
+    (chicken base) (chicken format) (chicken foreign)
+    (scheme char)
+    (srfi 4) (srfi 128) (srfi 146) (srfi 207)
+    (chicken foreign))
+ 
+  (export
+    parse-go-sum-line parse-go-sum-file go-sum-line? go-sum-module go-sum-version go-sum-path go-sum-hash)
+
+  (begin
+    (define-record-type <go-sum-line>
+      (make-go-sum-line module version path hash)
+      go-sum-line?
+      (module go-sum-module)
+      (version go-sum-version)
+      (path go-sum-path)
+      (hash go-sum-hash))
+
+    (define-record-printer (<go-sum-line> sum out)
+      (fprintf out "#<go-sum ~A ~A~A h1:~A>"
+        (go-sum-module sum)
+        (go-sum-version sum)
+        (if (go-sum-path sum) (go-sum-path sum) "")
+        (bytevector->base64 (go-sum-hash sum))))
+  
+    (define (string-find str index char)
+      (cond
+        ((= index (string-length str)) #f)
+        ((char=? (string-ref str index) char) index)
+        (else (string-find str (+ index 1) char))))
+
+    (define (parse-go-sum-line line)
+      (define version-space-index (string-find line 0 #\space))
+      (unless version-space-index (error "go.sum line contains no space characters"))
+      (define hash-space-index (string-find line (+ version-space-index 1) #\space))
+      (unless hash-space-index (error "go.sum line contains only one space character"))
+      (when (string-find line (+ hash-space-index 1) #\space) (error "go.sum line contains too many space characters"))
+      (define module-path (string-copy line 0 version-space-index))
+      (define version (string-copy line (+ version-space-index 1) hash-space-index))
+      (define hash (string-copy line (+ hash-space-index 1)))
+      (unless (string=? (string-copy hash 0 3) "h1:") (error "go.sum line has invalid algorithm for hash" hash))
+      (define path #f)
+      (define path-index (string-find version 0 #\/))
+      (when path-index
+        (set! path (string-copy version path-index))
+        (set! version (string-copy version 0 path-index)))
+      (make-go-sum-line module-path version path (base64->bytevector (string-copy hash 3))))
+
+    (define (parse-go-sum-file port)
+      (do ((parsed '())
+           (line "" (read-line port)))
+          ((eof-object? line) (list->vector (reverse parsed)))
+          (unless (string=? line "") (set! parsed (cons (parse-go-sum-line line) parsed)))))))
+