summaryrefslogtreecommitdiff
path: root/lisp/env.el
diff options
context:
space:
mode:
Diffstat (limited to 'lisp/env.el')
-rw-r--r--lisp/env.el154
1 files changed, 115 insertions, 39 deletions
diff --git a/lisp/env.el b/lisp/env.el
index b0235754906..4538e2dd715 100644
--- a/lisp/env.el
+++ b/lisp/env.el
@@ -36,6 +36,8 @@
;;; Code:
+(eval-when-compile (require 'cl))
+
;; History list for environment variable names.
(defvar read-envvar-name-history nil)
@@ -45,14 +47,15 @@ Optional second arg MUSTMATCH, if non-nil, means require existing envvar name.
If it is also not t, RET does not exit if it does non-null completion."
(completing-read prompt
(mapcar (lambda (enventry)
- (list (if enable-multibyte-characters
- (decode-coding-string
- (substring enventry 0
- (string-match "=" enventry))
- locale-coding-system t)
- (substring enventry 0
- (string-match "=" enventry)))))
- process-environment)
+ (let ((str (substring enventry 0
+ (string-match "=" enventry))))
+ (if (multibyte-string-p str)
+ (decode-coding-string
+ str locale-coding-system t)
+ str)))
+ (append process-environment
+ ;;(frame-environment)
+ ))
nil mustmatch nil 'read-envvar-name-history))
;; History list for VALUE argument to setenv.
@@ -88,17 +91,52 @@ Use `$$' to insert a single dollar sign."
start (+ (match-beginning 0) 1)))))
string))
-;; Fixme: Should `process-environment' be recoded if LC_CTYPE &c is set?
+
+(defun setenv-internal (env variable value keep-empty)
+ "Set VARIABLE to VALUE in ENV, adding empty entries if KEEP-EMPTY.
+Changes ENV by side-effect, and returns its new value."
+ (let ((pattern (concat "\\`" (regexp-quote variable) "\\(=\\|\\'\\)"))
+ (case-fold-search nil)
+ (scan env)
+ prev found)
+ ;; Handle deletions from the beginning of the list specially.
+ (if (and (null value)
+ (not keep-empty)
+ env
+ (stringp (car env))
+ (string-match pattern (car env)))
+ (cdr env)
+ ;; Try to find existing entry for VARIABLE in ENV.
+ (while (and scan (stringp (car scan)))
+ (when (string-match pattern (car scan))
+ (if value
+ (setcar scan (concat variable "=" value))
+ (if keep-empty
+ (setcar scan variable)
+ (setcdr prev (cdr scan))))
+ (setq found t
+ scan nil))
+ (setq prev scan
+ scan (cdr scan)))
+ (if (and (not found) (or value keep-empty))
+ (cons (if value
+ (concat variable "=" value)
+ variable)
+ env)
+ env))))
+
+;; Fixme: Should the environment be recoded if LC_CTYPE &c is set?
(defun setenv (variable &optional value substitute-env-vars)
"Set the value of the environment variable named VARIABLE to VALUE.
VARIABLE should be a string. VALUE is optional; if not provided or
nil, the environment variable VARIABLE will be removed.
-Interactively, a prefix argument means to unset the variable.
-Interactively, the current value (if any) of the variable
-appears at the front of the history list when you type in the new value.
-Interactively, always replace environment variables in the new value.
+Interactively, a prefix argument means to unset the variable, and
+otherwise the current value (if any) of the variable appears at
+the front of the history list when you type in the new value.
+This function always replaces environment variables in the new
+value when called interactively.
SUBSTITUTE-ENV-VARS, if non-nil, means to substitute environment
variables in VALUE with `substitute-env-vars', which see.
@@ -138,48 +176,86 @@ a side-effect."
(if (and value (multibyte-string-p value))
(setq value (encode-coding-string value locale-coding-system)))
(if (string-match "=" variable)
- (error "Environment variable name `%s' contains `='" variable)
- (let ((pattern (concat "\\`" (regexp-quote (concat variable "="))))
- (case-fold-search nil)
- (scan process-environment)
- found)
- (if (string-equal "TZ" variable)
- (set-time-zone-rule value))
- (while scan
- (cond ((string-match pattern (car scan))
- (setq found t)
- (if (eq nil value)
- (setq process-environment (delq (car scan)
- process-environment))
- (setcar scan (concat variable "=" value)))
- (setq scan nil)))
- (setq scan (cdr scan)))
- (or found
- (if value
- (setq process-environment
- (cons (concat variable "=" value)
- process-environment))))))
+ (error "Environment variable name `%s' contains `='" variable))
+ (if (string-equal "TZ" variable)
+ (set-time-zone-rule value))
+ (setq process-environment (setenv-internal process-environment
+ variable value t))
value)
-(defun getenv (variable)
+(defun getenv (variable &optional frame)
"Get the value of environment variable VARIABLE.
VARIABLE should be a string. Value is nil if VARIABLE is undefined in
the environment. Otherwise, value is a string.
-This function consults the variable `process-environment'
-for its value."
+If optional parameter FRAME is non-nil, then it should be a
+frame. This function will look up VARIABLE in its 'environment
+parameter.
+
+Otherwise, this function searches `process-environment' for
+VARIABLE. If it is not found there, then it continues the search
+in the environment list of the selected frame."
(interactive (list (read-envvar-name "Get environment variable: " t)))
(let ((value (getenv-internal (if (multibyte-string-p variable)
(encode-coding-string
variable locale-coding-system)
- variable))))
+ variable)
+ frame)))
(if (and enable-multibyte-characters value)
(setq value (decode-coding-string value locale-coding-system)))
(when (interactive-p)
(message "%s" (if value value "Not set")))
value))
+(defun environment (&optional frame)
+ "Return a list of environment variables with their values.
+Each entry in the list is a string of the form NAME=VALUE.
+
+The returned list can not be used to change environment
+variables, only read them. See `setenv' to do that.
+
+If optional parameter FRAME is non-nil, then it should be a
+frame. The function returns the environment of that frame.
+
+The list is constructed by concatenating the elements of
+`process-environment' and the 'environment parameter of the
+selected frame, and removing duplicated and empty values.
+
+Non-ASCII characters are encoded according to the initial value of
+`locale-coding-system', i.e. the elements must normally be decoded for use.
+See `setenv' and `getenv'."
+ (let* ((env (append process-environment
+ ;; (frame-environment frame)
+ nil))
+ (scan env)
+ prev seen)
+ ;; Remove unset variables from the beginning of the list.
+ (while (and env
+ (or (not (stringp (car env)))
+ (not (string-match "=" (car env)))))
+ (or (member (car env) seen)
+ (setq seen (cons (car env) seen)))
+ (setq env (cdr env)
+ scan env))
+ (let (name)
+ (while scan
+ (cond ((or (not (stringp (car scan)))
+ (not (string-match "=" (car scan))))
+ ;; Unset variable.
+ (or (member (car scan) seen)
+ (setq seen (cons (car scan) seen)))
+ (setcdr prev (cdr scan)))
+ ((member (setq name (substring (car scan) 0 (string-match "=" (car scan)))) seen)
+ ;; Duplicated variable.
+ (setcdr prev (cdr scan)))
+ (t
+ ;; New variable.
+ (setq seen (cons name seen))))
+ (setq prev scan
+ scan (cdr scan))))
+ env))
+
(provide 'env)
-;;; arch-tag: b7d6a8f7-bc81-46db-8e39-8d721d4ed0b8
+;; arch-tag: b7d6a8f7-bc81-46db-8e39-8d721d4ed0b8
;;; env.el ends here