[debian-devel:11687] Re: kernel-image-2.2.14-compact(was Re:jfbterm)

[Junichi Uekawa <dancer@xxxxxxxxxxxxx>]

何か、色々気になったので、特にバッファオーバーランをチェックしてないのが気になったので、
ちょっといじってみました。


bash-2.01$ diff -u shrink_eucja.orig.c shrink_eucja.c
--- shrink_eucja.orig.c	Sun Feb 20 09:59:15 2000
+++ shrink_eucja.c	Sun Feb 20 10:19:10 2000
@@ -1,35 +1,38 @@
 /*
  * shrink_eucja():
- * insert '\n' into japanese by specified character numbers.
+ * insert '\n' into text taking Japanese-multibyte into consideration.
+ * Making the line at most maxlinelen+1 bytes long.
+ * Note: when maxlinelen < 3, the result will be 4 bytes long.
+ * Patch copyright (c) 2000 Junichi Uekawa, see GPL version 2 or later for license
  */
 
 #include <stdio.h>
 #include <errno.h>
 #include <stdlib.h>
 
-#define check_left(width)			\
-	do {					\
-	  if (count + (width) > maxlen)		\
+#define check_remaining(width)			\
+	 {					\
+	  if (count + (width) > maxlinelen)		\
 	    {					\
 	      dest[bp++] = '\n';			\
 	      count = 0;			\
 	    }					\
-	} while(0)
+	} 
 
 #define copy_one_octet		\
 	if (*sp == '\0')	\
 	  break;		\
 	else {			\
 	  dest[bp++] = *sp++;    \
-	  count++;		\
+	  if (++count >= maxbuffersize)return NULL;\
 	}
 
 char *
-shrink_eucja(char *dest, char *source, int maxlen)
+shrink_eucja(char *dest, char *source, int maxlinelen, int maxbuffersize)
 {
   unsigned char *sp = (unsigned char *)source;
-  unsigned int count = 0, bp = 0;
-
+  unsigned int count = 0, bp = 0;  
+  
   while (*sp) 
     {
       /*
@@ -49,7 +52,7 @@
        */
       else if (0x21 <= *sp && *sp <= 0x7E)
 	{
-	  check_left(1);
+	  check_remaining(1);
 	  copy_one_octet;
 	}
       /*
@@ -59,7 +62,7 @@
        */
       else if (0xA1 <= *sp && *sp <= 0xFE)
 	{
-	  check_left(2);
+	  check_remaining(2);
 	  copy_one_octet;
 	  copy_one_octet;
 	}
@@ -70,7 +73,7 @@
        */
       else if (*sp == 0x8E)
 	{
-	  check_left(1);
+	  check_remaining(1);
 	  copy_one_octet;
 	  copy_one_octet;
 	}
@@ -81,17 +84,17 @@
        */
       else if (*sp == 0x8F)
 	{
-	  check_left(2);
+	  check_remaining(2);
 	  copy_one_octet;
 	  copy_one_octet;
 	  copy_one_octet;
 	}
       /*
-       * another...
+       * others
        */
       else
 	{
-	  check_left(1);
+	  check_remaining(1);
 	  copy_one_octet;
 	}
     }
@@ -123,7 +126,7 @@
   char buf[BUFSIZ], buf2[BUFSIZ];
   
   while (read(fd, buf, BUFSIZ))
-    puts(shrink_eucja(buf2, buf, maxlen));
+    puts(shrink_eucja(buf2, buf, maxlen, BUFSIZ));
 
   return 0;
 }