gnucash/bindings/guile/c-interface.scm
John Ralls f4c27d4494 Move gnc_ui_account_get_tax_info_string to gnc-locale-tax.c
To prevent a circular dependency between libgnc-app-utils and
libgnucash-guile.
2022-07-17 10:00:23 -07:00

82 lines
3.6 KiB
Scheme

;; This program is free software; you can redistribute it and/or
;; modify it under the terms of the GNU General Public License as
;; published by the Free Software Foundation; either version 2 of
;; the License, or (at your option) any later version.
;;
;; This program is distributed in the hope that it will be useful,
;; but WITHOUT ANY WARRANTY; without even the implied warranty of
;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
;; GNU General Public License for more details.
;;
;; You should have received a copy of the GNU General Public License
;; along with this program; if not, contact:
;;
;; Free Software Foundation Voice: +1-617-542-5942
;; 51 Franklin Street, Fifth Floor Fax: +1-617-542-2652
;; Boston, MA 02110-1301, USA gnu@gnu.org
(define-module (gnucash app-utils c-interface))
(use-modules (ice-9 match))
(use-modules (gnucash core-utils)
(gnucash utilities))
(export gnc:make-string-database)
(export gnc:call-with-error-handling)
(export gnc:apply-with-error-handling)
(export gnc:eval-string-with-error-handling)
(export gnc:backtrace-if-exception)
(define (gnc:call-with-error-handling cmd args)
(let ((captured-stack #f)
(captured-error #f)
(result #f))
(catch #t
(lambda ()
;; Execute the code in which you want to catch errors here.
(cond
((procedure? cmd) (set! result (apply cmd args)))
((string? cmd) (set! result (eval-string cmd)))))
(lambda (key . parameters)
;; Put the code which you want to handle an error after the
;; stack has been unwound here.
(set! captured-error
(call-with-output-string
(lambda (port)
(display-backtrace captured-stack port)
(newline port)
(print-exception port #f key parameters)))))
(lambda (key . parameters)
;; Capture the stack here, cut the last 3 frames which are
;; make-stack, this one, and the throw handler.
(set! captured-stack (make-stack #t 3))))
(list result captured-error)))
;; gnc:eval-string-with-error-handling will evaluate the input string (cmd)
;; an captures any exception that would be generated. It returns
;; a list with 2 elements: the output of the evaluation and a backtrace.
;; The first may be set if string evaluation did generate
;; output, the latter is set when an exception was caught.
;; We'll use this to wrap guile calls in C(++), allowing
;; the C(++) code to decide how to handle the errors.
(define (gnc:eval-string-with-error-handling cmd)
(gnc:call-with-error-handling cmd '()))
;; gnc:apply-with-error-handling will call guile's apply to run func with args
;; an captures any exception that would be generated. It returns
;; a list with 2 elements: the output of the evaluation and a backtrace.
;; The first may be set if the result of the apply did generate
;; output, the latter is set when an exception was caught.
;; We'll use this to wrap guile calls in C(++), allowing
;; the C(++) code to decide how to handle the errors.
(define (gnc:apply-with-error-handling func args)
(gnc:call-with-error-handling func args))
(define (gnc:backtrace-if-exception proc . args)
(match (gnc:apply-with-error-handling proc args)
((result #f) result)
((_ captured-error)
(display captured-error (current-error-port))
(when (defined? 'gnc:warn) (gnc:warn captured-error))
#f)))