Remove db as a global variable

There's no need for it to be a global variable.

linkwave.scm

@@ -15,11 +15,11 @@
   (format #t "~a~%  ~a~%  ~a~%  ~a~%~%" (string-no-null name) (string-no-null description)
           (string-no-null url) (seconds->string seconds)))
 
-(define (add-tag name)
+(define (add-tag db name)
   (execute db "INSERT INTO tag VALUES (?)" name)
   (last-insert-rowid db))
 
-(define (add-bookmark url name description tags)
+(define (add-bookmark db url name description tags)
   (execute db "INSERT INTO bookmark VALUES (?, STRFTIME('%s'), ?, ?)"
            url name description)
   (let ((bookmark-id (last-insert-rowid db)))
@@ -29,7 +29,7 @@
                    (set! tag-id (first-result db "SELECT rowid FROM tag WHERE name = ?" tag))
                    (exn (exn sqlite3)
                         (if (eq? (get-condition-property exn 'sqlite3 'status) 'done)
-                            (set! tag-id (add-tag tag))
+                            (set! tag-id (add-tag db tag))
                             (signal exn))))
                   (execute db "INSERT INTO bookmark_tag VALUES (?, ?)"
                            bookmark-id tag-id)))
@@ -41,17 +41,16 @@
            (string= (substring str 0 8) "https://"))))
 
 (define (main args)
-  (if (null? args)
-      (for-each-row print-row db "select * from bookmark")
-      (cond
-       ((url-string? (car args))
-        (with-transaction
-         db (lambda () (add-bookmark (car args) (cadr args) (caddr args) (cdddr args)) #t)))
-       (else
-        (format #t "Unrecognized option: ~a~%" (car args))))))
+  (let ((db (open-database (data-file "linkwave.db"))))
+    (if (null? args)
+        (for-each-row print-row db "select * from bookmark")
+        (cond
+         ((url-string? (car args))
+          (with-transaction
+           db (lambda () (add-bookmark db (car args) (cadr args) (caddr args) (cdddr args)) #t)))
+         (else
+          (format #t "Unrecognized option: ~a~%" (car args)))))
 
-(define db (open-database (data-file "linkwave.db")))
+    (finalize! db #t)))
 
 (main (command-line-arguments))
-
-(finalize! db #t)