Fix battery detection for non-Linux systems

Some non-Linux systems do not have a `/sys/` directory. Therefore,
check it only if we are in a Linux system.

Fixes #19

README.org

@@ -9,7 +9,7 @@
 akin to ~fish_greeting~ but for Eshell. But an image is worth a thousand
 words, let’s see how it looks like:
 
-#+caption: Screenshot of the default Eshell information banner
+#+caption: Screenshot of the default Eshell information banner (using the nord theme from ~doom-themes~)
 [[file:img/screenshot.png]]
 
 This will be displayed every time you open a new Eshell instance, or
@@ -22,15 +22,23 @@ macOS. PR are welcome if you want to fix that!
 * Table of Contents                                                :TOC_2_gh:
 - [[#introduction][Introduction]]
 - [[#recent-breaking-changes][Recent Breaking Changes]]
+  - [[#081][~0.8.1~]]
   - [[#070][~0.7.0~]]
 - [[#installation][Installation]]
 - [[#customizing][Customizing]]
+  - [[#custom-variables][Custom Variables]]
+  - [[#faces][Faces]]
 - [[#my-computer-doesnt-have-a-battery-will-this-still-work][My computer doesn’t have a battery, will this still work?]]
 - [[#advice-for-windows-users][Advice for Windows users]]
 - [[#contributing][Contributing]]
 - [[#license][License]]
 
 * Recent Breaking Changes
+** ~0.8.1~
+Version ~0.8.1~ removes the optional argument ~REMOTE~ from
+~eshell-info-banner--executable-find~. It now only acts according to the
+user’s preference set with ~eshell-info-banner-tramp-aware~.
+
 ** ~0.7.0~
 Version ~0.7.0~ renames several functions to conform with the Elisp
 Coding Conventions.
@@ -89,6 +97,7 @@ There is probably a similar way to install it with pure ~straight.el~ or
 a PR to add some more installation instructions!
 
 * Customizing
+** Custom Variables
 A couple of variables can be edited by the user in order to configure
 ~eshell-info-banner.el~:
 - ~eshell-info-banner-partition-prefixes~ :: Filter for which
@@ -143,7 +152,19 @@ A couple of variables can be edited by the user in order to configure
   this custom variable.
 
   Default value: ~duf~
+- ~eshell-info-banner-file-size-flavor~ :: This variable reflects the
+  possible values passed to the function ~file-size-human-readable~. It
+  can hold one of these three values:
+  - ~nil~
+  - ~si~
+  - ~iec~
+  Since the value ~iec~ generates longer file size prefixes, progress
+  bars become slightly shorter. For more details on this option, see
+  the documentation of ~file-size-human-readable~.
 
+  Default value: ~nil~
+
+** Faces
 Don’t like the colors used by the package? They should follow by
 default your theme, but you can customize the following faces:
 - ~eshell-info-banner-background-face~ :: Used for filling the empty

eshell-info-banner.el

@@ -2,7 +2,7 @@
 
 ;; Author: Lucien Cartier-Tilet <lucien@phundrak.com>
 ;; Maintainer: Lucien Cartier-Tilet <lucien@phundrak.com>
-;; Version: 0.7.7
+;; Version: 0.8.3
 ;; Package-Requires: ((emacs "25.1") (f "0.20") (s "1"))
 ;; Homepage: https://github.com/Phundrak/eshell-info-banner.el
 
@@ -65,7 +65,11 @@
 
 (eval-when-compile
   (defconst eshell-info-banner--macos-versions
-    '(("10.4"  . "Mac OS X Tiger")
+    '(("10.0"  . "Mac OS X Cheetah")
+      ("10.1"  . "Mac OS X Puma")
+      ("10.2"  . "Mac OS X Jaguar")
+      ("10.3"  . "Mac OS X Panther")
+      ("10.4"  . "Mac OS X Tiger")
       ("10.5"  . "Mac OS X Leopard")
       ("10.6"  . "Mac OS X Snow Leopard")
       ("10.7"  . "Mac OS X Lion")
@@ -84,31 +88,14 @@
       ("11.3"  . "macOS Big Sur")
       ("11.4"  . "macOS Big Sur")
       ("11.5"  . "macOS Big Sur")
-      ("11.6"  . "macOS Big Sur"))
+      ("11.6"  . "macOS Big Sur")
+      ("12.0"  . "macOS Monterey")
+      ("12.1"  . "macOS Monterey")
+      ("12.2"  . "macOS Monterey"))
     "Versions of OSX and macOS and their name."))
 
-
-;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
-                                        ;                Macros               ;
-;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
-
-(defmacro eshell-info-banner--with-face (str &rest properties)
-  "Helper macro for applying face `PROPERTIES' to `STR'."
-  `(propertize ,str 'face (list ,@properties)))
-
-(defun eshell-info-banner--executable-find (program &optional remote)
-  (if (version< emacs-version "27.1")
-      (let ((default-directory (if (and eshell-info-banner-tramp-aware
-                                        remote)
-                                   default-directory
-                                 "~")))
-        (executable-find program))
-    (executable-find program remote)))
-
-(defun eshell-info-banner--shell-command-to-string (command)
-  "Execute shell command COMMAND and return its output as a string.
-Ensures the command is ran with LANG=C."
-  (shell-command-to-string (format "LANG=C %s" command)))
+(defconst eshell-info-banner--posix-shells '("bash" "zsh" "sh")
+  "List of POSIX-compliant shells to run external commands through.")
 
 
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
@@ -163,6 +150,19 @@ Ensures the command is ran with LANG=C."
   :type 'list
   :version "0.3.0")
 
+(defun eshell-info-banner--executable-find (program)
+  "Find PROGRAM executable, possibly on a remote machine.
+This is a wrapper around `executable-find' in order to avoid
+issues with older versions of the functions only accepting one
+argument. `executable-find'’s remote argument has the value of
+`eshell-info-banner-tramp-aware'."
+  (if (version< emacs-version "27.1")
+      (let ((default-directory (if eshell-info-banner-tramp-aware
+                                   default-directory
+                                 "~")))
+        (executable-find program))
+    (executable-find program eshell-info-banner-tramp-aware)))
+
 (defcustom eshell-info-banner-duf-executable "duf"
   "Path to the `duf' executable."
   :group 'eshell-info-banner
@@ -180,6 +180,14 @@ Ensures the command is ran with LANG=C."
   :safe #'booleanp
   :version "0.5.0")
 
+(defcustom eshell-info-banner-file-size-flavor nil
+  "Display sizes with IEC prefixes."
+  :group 'eshell-info-banner
+  :type '(radio (const :tag "Default" nil)
+                (const :tag "SI" si)
+                (const :tag "IEC" iec))
+  :version "0.8.0")
+
 
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
                                         ;                Faces                ;
@@ -205,6 +213,45 @@ Ensures the command is ran with LANG=C."
   "Face for `eshell-info-banner' progress bars displaying critical levels."
   :group 'eshell-info-banner)
 
+
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+                                        ;         Macros and Utilities        ;
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+
+(defmacro eshell-info-banner--with-face (str &rest properties)
+  "Helper macro for applying face `PROPERTIES' to `STR'."
+  `(propertize ,str 'face (list ,@properties)))
+
+(defun eshell-info-banner--shell-command-to-string (command)
+  "Execute shell command COMMAND and return its output as a string.
+Ensures the command is ran with LANG=C."
+  (let ((shell (or (seq-find (lambda (shell)
+                              (eshell-info-banner--executable-find shell))
+                            eshell-info-banner--posix-shells)
+                  "sh")))
+    (with-temp-buffer
+      (call-process shell nil t nil "-c" (concat "LANG=C " command))
+      (buffer-string))))
+
+(defun eshell-info-banner--progress-bar-without-prefix (bar-length used total &optional newline)
+  "Display a progress bar without its prefix.
+Display a progress bar of BAR-LENGTH length, followed by an
+indication of how full the memory is with a human readable USED
+and TOTAL size."
+  (let ((percentage (if (= used 0)
+                        0
+                      (/ (* 100 used) total))))
+    (concat (eshell-info-banner--progress-bar bar-length percentage)
+            (format (if (equal eshell-info-banner-file-size-flavor 'iec)
+                        " %8s / %-8s (%3s%%)%s"
+                      " %6s / %-6s (%3s%%)%s")
+                    (file-size-human-readable used eshell-info-banner-file-size-flavor)
+                    (file-size-human-readable total eshell-info-banner-file-size-flavor)
+                    (eshell-info-banner--with-face
+                     (number-to-string percentage)
+                     :inherit (eshell-info-banner--get-color-percentage percentage))
+                    (if newline "\n" "")))))
+
 
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
                                         ;          Internal functions         ;
@@ -220,7 +267,7 @@ If the executable `uptime' is not found, return nil."
     (let ((uptime-str (eshell-info-banner--shell-command-to-string "uptime -p")))
       (if (not (seq-some (lambda (keyword)
                            (string-match-p keyword uptime-str))
-                         '("invalid" "illegal")))
+                         '("invalid" "illegal" "unknown")))
           (s-chop-prefix "up " (s-trim uptime-str))
         (let ((uptime-str (eshell-info-banner--shell-command-to-string "uptime")))
           (save-match-data
@@ -300,8 +347,8 @@ chosen. Relies on the `duf' command."
                    :path    (if (> (length mount-point) eshell-info-banner-shorten-path-from)
                                 (eshell-info-banner--abbr-path mount-point t)
                               mount-point)
-                   :size    (file-size-human-readable total)
-                   :used    (file-size-human-readable used)
+                   :size    total
+                   :used    used
                    :percent percent)))
               partitions)))
 
@@ -313,15 +360,15 @@ Common function between
 otherwise differ solely on the position of the mount point in the
 partition list. Its position is given by the argument
 MOUNT-POSITION."
-  (let ((partitions (cdr (split-string (eshell-info-banner--shell-command-to-string "df -lH")
+  (let ((partitions (cdr (split-string (eshell-info-banner--shell-command-to-string "df -l")
                                        (regexp-quote "\n")
                                        t))))
     (cl-remove-if #'null
                   (mapcar (lambda (partition)
                             (let* ((partition  (split-string partition " " t))
                                    (filesystem (nth 0 partition))
-                                   (size       (nth 1 partition))
-                                   (used       (nth 2 partition))
+                                   (size       (string-to-number (nth 1 partition)))
+                                   (used       (string-to-number (nth 2 partition)))
                                    (percent    (nth 4 partition))
                                    (mount      (nth mount-position partition)))
                               (when (seq-some (lambda (prefix)
@@ -386,20 +433,16 @@ Return detected partitions as a list of structs."
 
 For TEXT-PADDING and BAR-LENGTH, see the documentation of
 `eshell-info-banner--display-memory'."
-  (let ((percentage (eshell-info-banner--mounted-partitions-percent partition)))
-    (concat (s-pad-right text-padding
-                         "."
-                         (eshell-info-banner--with-face
-                          (eshell-info-banner--mounted-partitions-path partition)
-                          :weight 'bold))
-            ": "
-            (eshell-info-banner--progress-bar bar-length percentage)
-            (format " %6s / %-6s (%3s%%)"
-                    (eshell-info-banner--mounted-partitions-used partition)
-                    (eshell-info-banner--mounted-partitions-size partition)
-                    (eshell-info-banner--with-face
-                     (number-to-string percentage)
-                     :inherit (eshell-info-banner--get-color-percentage percentage))))))
+  (concat (s-pad-right text-padding
+                       "."
+                       (eshell-info-banner--with-face
+                        (eshell-info-banner--mounted-partitions-path partition)
+                        :weight 'bold))
+          ": "
+          (eshell-info-banner--progress-bar-without-prefix
+           bar-length
+           (eshell-info-banner--mounted-partitions-used partition)
+           (eshell-info-banner--mounted-partitions-size partition))))
 
 (defun eshell-info-banner--display-partitions (text-padding bar-length)
   "Display the detected mounted partitions of the system.
@@ -424,19 +467,78 @@ For TEXT-PADDING and BAR-LENGTH, see the documentation of
                         "\n"
                         t)))
 
-(defun eshell-info-banner--get-memory-unix ()
-  "Get memory usage for UNIX systems.
-Compatible with Darwin and FreeBSD at least."
-  (let* ((command-to-mem (lambda (command)
-                           (string-to-number
+(defun eshell-info-banner--get-memory-unix-command-to-mem (command)
+  (string-to-number
+   (s-trim
+    (car (last
+          (split-string (eshell-info-banner--shell-command-to-string command)
+                        " "
+                        t))))))
+
+(defun eshell-info-banner--get-memory-netbsd ()
+  "Get memory usage for NetBSD systems.
+See `eshell-info-banner--get-memory'."
+  (let* ((total (eshell-info-banner--get-memory-unix-command-to-mem `("sysctl hw.physmem64")))
+         (used  (- total
+                   (* 1024 (string-to-number
                             (s-trim
-                             (cadr
-                              (split-string (eshell-info-banner--shell-command-to-string command)
-                                            " "
-                                            t)))))))
-    `(("RAM"
-       ,(apply command-to-mem '("sysctl hw.physmem"))
-       ,(apply command-to-mem '("sysctl hw.usermem"))))))
+                             (with-temp-buffer
+                               (insert-file-contents-literally "/proc/meminfo")
+                               (save-match-data
+                                 (string-match (rx bol
+                                                   "MemFree:"
+                                                   (* blank)
+                                                   (group (+ digit))
+                                                   (* blank)
+                                                   "kB")
+                                               (buffer-string))
+                                 (substring-no-properties (buffer-string)
+                                                          (match-beginning 1)
+                                                          (match-end 1))))))))))
+    `(("RAM" ,total ,used))))
+
+(defun eshell-info-banner--get-memory-darwin ()
+  "Get memory usage for Darwin systems.
+See `eshell-info-banner--get-memory'."
+  (let* ((total  (eshell-info-banner--get-memory-unix-command-to-mem "sysctl -n hw.memsize"))
+         (vmstat (with-temp-buffer
+                   (call-process "vm_stat" nil t nil)
+                   (buffer-string)))
+         (wired  (save-match-data
+                   (string-match (rx " wired" (* (not digit)) (+ blank) (group (+ digit)) ".")
+                                 vmstat)
+                   (* 1024 4
+                      (string-to-number (substring-no-properties vmstat
+                                                                 (match-beginning 1)
+                                                                 (match-end 1))))))
+         (active (save-match-data
+                   (string-match (rx " active" (* (not digit)) (+ blank) (group (+ digit)) ".")
+                                 vmstat)
+                   (* 1024 4
+                      (string-to-number (substring-no-properties vmstat
+                                                                 (match-beginning 1)
+                                                                 (match-end 1))))))
+         (compressed (save-match-data
+                       (if (string-match (rx " occupied" (* (not digit)) (+ blank) (group (+ digit)) ".")
+                                         vmstat)
+                           (* 1024 4
+                              (string-to-number (substring-no-properties vmstat
+                                                                         (match-beginning 1)
+                                                                         (match-end 1))))
+                         0))))
+    `(("RAM" ,total ,(+ wired active compressed)))))
+
+(defun eshell-info-banner--get-memory-unix ()
+  "Get memory usage for UNIX systems."
+  (cond ((and (equal system-type 'berkeley-unix)
+              (string-match-p "NetBSD" (eshell-info-banner--shell-command-to-string "uname")))
+         (eshell-info-banner--get-memory-netbsd))
+        ((equal system-type 'darwin)
+         (eshell-info-banner--get-memory-darwin))
+        (t
+         (let* ((total (eshell-info-banner--get-memory-unix-command-to-mem "sysctl hw.physmem"))
+                (used  (eshell-info-banner--get-memory-unix-command-to-mem "sysctl hw.usermem")))
+           `(("RAM" ,total ,used))))))
 
 (defun eshell-info-banner--get-memory-windows ()
   "Get memory usage for Window."
@@ -475,18 +577,9 @@ be displayed on the far right.
 
 `BAR-LENGTH' determines the length of the progress bar to be
 displayed."
-  (let ((percentage (if (= used 0)
-                        0
-                      (/ (* 100 used) total))))
-    (concat (s-pad-right text-padding "." type)
-            ": "
-            (eshell-info-banner--progress-bar bar-length percentage)
-            (format " %6s / %-6s (%3s%%)\n"
-                    (file-size-human-readable used)
-                    (file-size-human-readable total)
-                    (eshell-info-banner--with-face
-                     (number-to-string percentage)
-                     :inherit (eshell-info-banner--get-color-percentage percentage))))))
+  (concat (s-pad-right text-padding "." type)
+          ": "
+          (eshell-info-banner--progress-bar-without-prefix bar-length used total t)))
 
 (defun eshell-info-banner--display-memory (text-padding bar-length)
   "Display memories detected on your system.
@@ -562,7 +655,9 @@ The usage of `eshell-info-banner-warning-percentage' and
 thought of as the “percentage of discharge” of the computer.
 Thus, setting the warning at 75% will be translated as showing
 the warning face with a battery level of 25% or less."
-  (let ((battery-level (when (file-readable-p "/sys/") (battery))))
+  (let ((battery-level (unless (and (equal system-type 'gnu/linux)
+                                    (not (file-readable-p "/sys/")))
+                         (battery))))
     (if (or (null battery-level)
             (string= battery-level "Battery status not available")
             (string-match-p (regexp-quote "N/A") battery-level))
@@ -577,7 +672,7 @@ the warning face with a battery level of 25% or less."
                 (eshell-info-banner--progress-bar bar-length
                                                   percentage
                                                   t)
-                (s-repeat 17 " ")
+                (s-repeat (if (equal eshell-info-banner-file-size-flavor 'iec) 21 17) " ")
                 (format "(%3s%%)\n"
                         (eshell-info-banner--with-face
                          (number-to-string percentage)
@@ -644,7 +739,7 @@ If RELEASE-FILE is nil, use '/etc/os-release'."
                    (insert-file-contents (concat prefix "/bedrock/etc/bedrock-release"))
                    (buffer-string))))
         ;; Proxmox
-        ((eshell-info-banner--executable-find "pveversion" eshell-info-banner-tramp-aware)
+        ((eshell-info-banner--executable-find "pveversion")
          (let ((distro (eshell-info-banner--shell-command-to-string "pveversion")))
            (save-match-data
              (string-match "/\\([^/]+\\)/" distro)
@@ -652,9 +747,9 @@ If RELEASE-FILE is nil, use '/etc/os-release'."
                      (substring-no-properties distro
                                               (match-beginning 1)
                                               (match-end 1))))))
-        ((eshell-info-banner--executable-find "hostnamectl" eshell-info-banner-tramp-aware)
+        ((eshell-info-banner--executable-find "hostnamectl")
          (eshell-info-banner--get-os-information-from-hostnamectl))
-        ((eshell-info-banner--executable-find "lsb_release" eshell-info-banner-tramp-aware)
+        ((eshell-info-banner--executable-find "lsb_release")
          (eshell-info-banner--get-os-information-from-lsb-release))
         ((file-exists-p (concat prefix "/etc/os-release"))
          (eshell-info-banner--get-os-information-from-release-file))
@@ -719,26 +814,29 @@ build number)."
 (defun eshell-info-banner ()
   "Banner for Eshell displaying system information."
   (let* ((default-directory (if eshell-info-banner-tramp-aware default-directory "~"))
-         (system-info   (eshell-info-banner--get-os-information))
-         (os            (car system-info))
-         (kernel        (cdr system-info))
-         (hostname      (if  eshell-info-banner-tramp-aware
-                            (or (file-remote-p default-directory 'host) (system-name))
-                          (system-name)))
-         (uptime        (eshell-info-banner--get-uptime))
-         (partitions    (eshell-info-banner--get-mounted-partitions))
-         (left-padding  (eshell-info-banner--get-longest-path partitions))
-         (left-text     (max (length os)
-                             (length hostname)))
-         (left-length   (+ left-padding 2 left-text)) ; + ": "
-         (right-text    (+ (length "Kernel: ")
-                           (max (length uptime)
-                                (length kernel))))
-         (tot-width     (max (+ left-length right-text 3)
-                             eshell-info-banner-width))
-         (middle-padding (- tot-width right-text left-padding 4))
+         (system-info       (eshell-info-banner--get-os-information))
+         (os                (car system-info))
+         (kernel            (cdr system-info))
+         (hostname          (if  eshell-info-banner-tramp-aware
+                                (or (file-remote-p default-directory 'host) (system-name))
+                              (system-name)))
+         (uptime             (eshell-info-banner--get-uptime))
+         (partitions         (eshell-info-banner--get-mounted-partitions))
+         (left-padding       (eshell-info-banner--get-longest-path partitions))
+         (left-text          (max (length os)
+                                  (length hostname)))
+         (left-length        (+ left-padding 2 left-text)) ; + ": "
+         (right-text         (+ (length "Kernel: ")
+                                (max (length uptime)
+                                     (length kernel))))
+         (tot-width          (max (+ left-length right-text 3)
+                                  eshell-info-banner-width))
+         (middle-padding     (- tot-width right-text left-padding 4))
 
-         (bar-length    (- tot-width left-padding 4 23)))
+         (bar-length         (- tot-width left-padding 4 23))
+         (bar-length         (if (equal eshell-info-banner-file-size-flavor 'iec)
+                                 (- bar-length 4)
+                               bar-length)))
     (concat (format "%s\n" (s-repeat tot-width eshell-info-banner-progress-bar-char))
             (format "%s: %s Kernel.: %s\n"
                     (s-pad-right left-padding