emacs-framebuffer

commit 07ff446574552a2fac29d344766178712b8e3aa9
parent f34d745890917c9e2184a67f16c20c497a8dc151
Author: Tomas Hlavaty <tom@logand.com>
Date:   Sun, 24 May 2020 07:03:43 +0200

improve framebuffer-image-size

Diffstat:
M
emacs-framebuffer.el
 | 
118
++++++++++++++++++++++++++++++-------------------------------------------------

1 file changed, 45 insertions(+), 73 deletions(-)
diff --git a/emacs-framebuffer.el b/emacs-framebuffer.el
@@ -84,83 +84,55 @@
   (+ (framebuffer-next-u16le brook)
      (* 65536 (framebuffer-next-u16le brook))))
 
-(defun framebuffer-png-size (file)
-  (with-temp-buffer
-    (set-buffer-multibyte nil)
-    (insert-file-contents-literally file)
-    (let ((brook (framebuffer-buffer-brook)))
-      (when (and (= 137 (funcall brook))
-                 (= ?P (funcall brook))
-                 (= ?N (funcall brook))
-                 (= ?G (funcall brook))
-                 (= 13 (funcall brook))
-                 (= 10 (funcall brook))
-                 (= 26 (funcall brook))
-                 (= 10 (funcall brook))
-                 (<= 12 (framebuffer-next-u32 brook))
-                 (= ?I (funcall brook))
-                 (= ?H (funcall brook))
-                 (= ?D (funcall brook))
-                 (= ?R (funcall brook)))
-        (cons (framebuffer-next-u32 brook)
-              (framebuffer-next-u32 brook))))))
-
-(defun framebuffer-jpeg-size (file)
-  (with-temp-buffer
-    (set-buffer-multibyte nil)
-    (insert-file-contents-literally file)
-    (let ((brook (framebuffer-buffer-brook)))
-      (when (and (= #xff (framebuffer-next-u8 brook))
-                 (= #xd8 (framebuffer-next-u8 brook)))
-        (let ((n 0)
-              (m 0))
-          (while (not (member m '(#xc0 #xc1 #xc2 #xc3 #xc5 #xc6 #xc7 #xc8
-                                       #xc9 #xca #xcb #xcd #xc0e #xcf)))
-            (goto-char (+ (point) n))
-            (while (= #xff (setq m (framebuffer-next-u8 brook))))
-            (setq n (- (framebuffer-next-u16 brook) 2)))
-          (framebuffer-next-u8 brook)
-          (let ((h (framebuffer-next-u16 brook)))
-            (cons (framebuffer-next-u16 brook)
-                  h)))))))
-
-(defun framebuffer-bmp-size (file)
-  (with-temp-buffer
-    (set-buffer-multibyte nil)
-    (insert-file-contents-literally file)
-    (let ((brook (framebuffer-buffer-brook)))
-      (when (and (= ?B (framebuffer-next-u8 brook))
-                 (= ?M (framebuffer-next-u8 brook)))
-        (dotimes (i 16)
-          (framebuffer-next-u8 brook))
-        (cons (framebuffer-next-u32le brook)
-              (framebuffer-next-u32le brook))))))
-
-(defun framebuffer-gif-size (file)
+(defun framebuffer-image-size (file)
   (with-temp-buffer
     (set-buffer-multibyte nil)
     (insert-file-contents-literally file)
     (let ((brook (framebuffer-buffer-brook)))
-      (when (and (= ?G (framebuffer-next-u8 brook))
-                 (= ?I (framebuffer-next-u8 brook))
-                 (= ?F (framebuffer-next-u8 brook))
-                 (= ?8 (framebuffer-next-u8 brook))
-                 (member (framebuffer-next-u8 brook) '(?7 ?9))
-                 (= ?a (framebuffer-next-u8 brook)))
-        (cons (framebuffer-next-u16le brook)
-              (framebuffer-next-u16le brook))))))
-
-(defun framebuffer-image-size (file)
-  (let ((e (file-name-extension file)))
-    (cond
-     ((string-match "png\\|PNG" e)
-      (framebuffer-png-size file))
-     ((string-match "jpe?g\\|JPE?G" e)
-      (framebuffer-jpeg-size file))
-     ((string-match "bmp\\|BMP" e)
-      (framebuffer-bmp-size file))
-     ((string-match "gif\\|GIF" e)
-      (framebuffer-gif-size file)))))
+      (case (funcall brook)
+        (137 ;; png
+         (when (and (= ?P (funcall brook))
+                    (= ?N (funcall brook))
+                    (= ?G (funcall brook))
+                    (= 13 (funcall brook))
+                    (= 10 (funcall brook))
+                    (= 26 (funcall brook))
+                    (= 10 (funcall brook))
+                    (<= 12 (framebuffer-next-u32 brook))
+                    (= ?I (funcall brook))
+                    (= ?H (funcall brook))
+                    (= ?D (funcall brook))
+                    (= ?R (funcall brook)))
+           (cons (framebuffer-next-u32 brook)
+                 (framebuffer-next-u32 brook))))
+        (#xff ;; jpeg
+         (when (= #xd8 (framebuffer-next-u8 brook))
+           (let ((n 0)
+                 (m 0))
+             (while (not (member m '(#xc0 #xc1 #xc2 #xc3 #xc5 #xc6 #xc7 #xc8
+                                          #xc9 #xca #xcb #xcd #xc0e #xcf)))
+               (goto-char (+ (point) n))
+               (while (= #xff (setq m (framebuffer-next-u8 brook))))
+               (setq n (- (framebuffer-next-u16 brook) 2))))
+           (framebuffer-next-u8 brook)
+           (let ((h (framebuffer-next-u16 brook)))
+             (cons (framebuffer-next-u16 brook)
+                   h))))
+        (?B ;; bmp
+         (when (= ?M (framebuffer-next-u8 brook))
+           (dotimes (i 16)
+             (framebuffer-next-u8 brook))
+           (cons (framebuffer-next-u32le brook)
+                 (framebuffer-next-u32le brook))))
+        (?G ;; gif
+         (when (and (= ?I (framebuffer-next-u8 brook))
+                    (= ?F (framebuffer-next-u8 brook))
+                    (= ?8 (framebuffer-next-u8 brook))
+                    (member (framebuffer-next-u8 brook) '(?7 ?9))
+                    (= ?a (framebuffer-next-u8 brook)))
+           (cons (framebuffer-next-u16le brook)
+                 (framebuffer-next-u16le brook))))
+        ))))
 
 (defun framebuffer-image-file (file)
   (interactive "fFile: ")