Files
emacs/lisp/emacsql/emacsql-sqlite-module.el
2025-11-25 19:52:03 +01:00

96 lines
3.5 KiB
EmacsLisp

;;; emacsql-sqlite-module.el --- EmacSQL back-end for SQLite using a module -*- lexical-binding:t -*-
;; This is free and unencumbered software released into the public domain.
;; Author: Jonas Bernoulli <emacs.emacsql@jonas.bernoulli.dev>
;; Maintainer: Jonas Bernoulli <emacs.emacsql@jonas.bernoulli.dev>
;; SPDX-License-Identifier: Unlicense
;;; Commentary:
;; This library provides an EmacSQL back-end for SQLite, which uses
;; the Emacs module provided by the `sqlite3' package.
;;; Code:
(require 'emacsql-sqlite)
(require 'sqlite3 nil t)
(declare-function sqlite3-open "ext:sqlite3-api")
(declare-function sqlite3-exec "ext:sqlite3-api")
(declare-function sqlite3-close "ext:sqlite3-api")
(defvar sqlite-open-readwrite)
(defvar sqlite-open-create)
(emacsql-register-reserved emacsql-sqlite-reserved)
(defclass emacsql-sqlite-module-connection (emacsql--sqlite-base) ()
"A connection to a SQLite database using a module.")
(cl-defmethod initialize-instance :after
((connection emacsql-sqlite-module-connection) &rest _)
(require (quote sqlite3))
(oset connection handle
(sqlite3-open (or (oref connection file) ":memory:")
sqlite-open-readwrite
sqlite-open-create))
(emacsql-sqlite-set-busy-timeout connection)
(emacsql connection [:pragma (= foreign-keys on)])
(emacsql-register connection))
(cl-defun emacsql-sqlite-module (file &key debug)
"Open a connected to database stored in FILE.
If FILE is nil use an in-memory database.
:debug LOG -- When non-nil, log all SQLite commands to a log
buffer. This is for debugging purposes."
(let ((connection (make-instance #'emacsql-sqlite-module-connection
:file file)))
(when debug
(emacsql-enable-debugging connection))
connection))
(cl-defmethod emacsql-live-p ((connection emacsql-sqlite-module-connection))
(and (oref connection handle) t))
(cl-defmethod emacsql-close ((connection emacsql-sqlite-module-connection))
(when (oref connection handle)
(sqlite3-close (oref connection handle))
(oset connection handle nil)))
(cl-defmethod emacsql-send-message
((connection emacsql-sqlite-module-connection) message)
(condition-case err
(let ((include-header emacsql-include-header)
(rows ()))
(sqlite3-exec (oref connection handle)
message
(lambda (_ row header)
(when include-header
(push header rows)
(setq include-header nil))
(push (mapcan (lambda (col)
(cond
((null col) (list nil))
((equal col "") (list ""))
((emacsql-sqlite-read-column col))))
row)
rows)))
(nreverse rows))
((db-error sql-error)
(pcase-let* ((`(,_ ,errmsg ,errcode) err)
(`(,_ ,_ ,signal ,errstr)
(assq errcode emacsql-sqlite-error-codes)))
(signal (or signal 'emacsql-error)
(list errmsg errcode nil errstr))))
(error
(signal 'emacsql-error (cdr err)))))
(cl-defmethod emacsql ((connection emacsql-sqlite-module-connection) sql &rest args)
(emacsql-send-message connection (apply #'emacsql-compile connection sql args)))
(provide 'emacsql-sqlite-module)
;;; emacsql-sqlite-module.el ends here