(in-package :cl-postgres)

​

;; These are used to synthesize reader and writer names for integer

;; reading/writing functions when the amount of bytes and the

;; signedness is known. Both the macro that creates the functions and

;; some macros that use them create names this way.

(eval-when (:compile-toplevel :load-toplevel :execute)

  (defun integer-reader-name (bytes signed)

    (intern (with-standard-io-syntax

              (format nil "~a~a~a~a" '#:read- (if signed "" '#:u) '#:int bytes))))

  (defun integer-writer-name (bytes signed)

    (intern (with-standard-io-syntax

              (format nil "~a~a~a~a" '#:write- (if signed "" '#:u) '#:int bytes)))))

​

(defmacro integer-reader (bytes)

  "Create a function to read integers from a binary stream."

  (let ((bits (* bytes 8)))

    (labels ((return-form (signed)

               (if signed

                   `(if (logbitp ,(1- bits) result)

                        (dpb result (byte ,(1- bits) 0) -1)

                        result)

                   `result))

             (generate-reader (signed)

               `(defun ,(integer-reader-name bytes signed) (socket)

                  (declare (type stream socket)

                           #.*optimize*)

                  ,(if (= bytes 1)

                       `(let ((result (the (unsigned-byte 8) (read-byte socket))))

                          (declare (type (unsigned-byte 8) result))

                          ,(return-form signed))

                       `(let ((result 0))