c++ emacs settings

;;;; C, C++ Development
;; Rtags
(defvar rtags-completions-enabled)
(setq rtags-completions-enabled nil)

(defun my-flycheck-irony-setup ()
  "Setup irony checker."
  (require 'flycheck-irony)
  (flycheck-select-checker 'irony))
(add-hook 'c-mode-hook #'my-flycheck-irony-setup)
(add-hook 'c++-mode-hook #'my-flycheck-irony-setup)
(add-hook 'objc-mode-hook #'my-flycheck-irony-setup)
;; completion
(add-hook 'irony-mode-hook #'irony-cdb-autosetup-compile-options)

(use-package flycheck-clang-analyzer
  :after flycheck-irony
  :config
  (flycheck-clang-analyzer-setup))

;; show docs at point
;; (require 'xah-lookup)
;; Uncomment the below line to use eww (Emacs Web Wowser)
;; (setq xah-lookup-browser-function 'eww)

(autoload 'xah-lookup-word-on-internet "xah-lookup")
(use-package xah-lookup
  :defer t)
(defvar xah-lookup-browser-function)
(defun xah-lookup-cppreference (&optional word)
  "Lookup definition of current WORD or text selection in URL."
  (interactive)
  (xah-lookup-word-on-internet
   word
   ;; Use � as a placeholder in the query URL.
   "http://en.cppreference.com/mwiki/index.php?search=�"
   xah-lookup-browser-function))

;; (require 'cc-mode)

;; Add shortcut for c++-mode
;; Another example with http://www.boost.org
(defun xah-lookup-boost (&optional word)
  "Lookup definition of current WORD or text selection in URL."
  (interactive)
  (xah-lookup-word-on-internet
   word
   "https://cse.google.com/cse?cx=011577717147771266991:jigzgqluebe&q=�"
   xah-lookup-browser-function))

(defvar c++-mode-map)
(defvar c-mode-map)
(defun xah-c++-setup ()
  "Setup xah-lookups for c++-mode."
  (require 'cc-mode)
  (define-key c++-mode-map (kbd "C-c b") #'xah-lookup-boost)
  (define-key c++-mode-map (kbd "C-c d") #'xah-lookup-cppreference))

(add-hook 'c++-mode-hook #'xah-c++-setup)

(declare-function rtags-eldoc "ext:rtags")
(defun my-cc-mode-hook ()
  "My hook for c & c++ modes."
  (require 'cc-mode)
  (local-set-key (kbd "C-c C-t") #'rtags-symbol-type)
  (local-set-key (kbd "C-c C-d") #'rtags-print-symbol-info)
  (local-set-key (kbd "M-.") (lambda ()
                               (interactive)
                               (xref-push-marker-stack)
                               (rtags-find-symbol-at-point)))
  (local-set-key (kbd "M-?") (lambda ()
                               (interactive)
                               (xref-push-marker-stack)
                               (rtags-find-references-at-point)))
  (local-set-key (kbd "C-'") #'company-irony-c-headers)
  (rtags-start-process-unless-running)
  (setq-local eldoc-documentation-function #'rtags-eldoc)
  (eldoc-mode +1)
  (irony-mode)
  (add-to-list 'company-backends '(company-irony company-irony-c-headers)))
(add-hook 'c++-mode-hook #'my-cc-mode-hook)
(add-hook 'c-mode-hook #'my-cc-mode-hook)
;; Semantic
;; (require 'cc-mode)
;; (require 'semantic)
;; (global-semanticdb-minor-mode 1)
;; (global-semantic-idle-scheduler-mode 1)
;; (semantic-mode 1)
;; (global-set-key (kbd "C-c C-j") 'semantic-ia-fast-jump)
;; (global-semantic-idle-summary-mode 1)

(use-package cmake-ide
  :defer 2
  :config
  (cmake-ide-setup))

;; Add cmake listfile names to the mode list.
(setq auto-mode-alist
      (append
       '(("CMakeLists\\.txt\\'" . cmake-mode))
       '(("\\.cmake\\'" . cmake-mode))
       auto-mode-alist))
(defun my-cmake-font-lock ()
  "Activate font lock for cmake."
  (require 'cmake-font-lock)
  (cmake-font-lock-activate))
(add-hook 'cmake-mode-hook #'my-cmake-font-lock)

(defvar company-c-headers-path-user)
(defun company-set-c-headers-user-path ()
  "Set path for selected directory with project headers."
  (interactive)
  (let
      ((dir
        (expand-file-name (read-directory-name
                           "Select project directory:" default-directory))))
    (setq company-c-headers-path-user (list (concat dir "/include")))))