update Hacking_of_LHa

diff --git a/ChangeLog b/ChangeLog
index c6e5f6d..d13cd85 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+2008-06-24  Koji Arai  <arai@users.sourceforge.jp>
+
+       * Hacking_of_LHa: updated.
+
 2008-05-14  Koji Arai  <arai@users.sourceforge.jp>
 
        * src/lhext.c (extract_one): The -t command should not affect extracting file attributes.

diff --git a/Hacking_of_LHa b/Hacking_of_LHa
index 0489229..1295e4d 100644 (file)
--- a/Hacking_of_LHa
+++ b/Hacking_of_LHa
@@ -3841,13 +3841,14 @@ buf |  32 | c1  | c2  | len |    off    |  ...
 
 ----------------------------------------------------------------------------
 
-output_mask    128   64    32                16    8     4     2     1
-        +-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+
-buf     |  32 | c1  | c2  | len |    off    |  c3 |  c4 |  c5 |  c6 |  c7 |
-        +-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+
-        cpos                                                             /
-                                                                        /
+output_mask  128  64   32             16   8              4    2    1
+        +----+----+----+----+----+----+----+----+----+----+----+----+----+
+buf     | 40 | c1 | c2 |len |   off   | c4 |len |   off   | c6 | c7 | c8 |
+        +----+----+----+----+----+----+----+----+----+----+----+----+----+
+        cpos                                                            /
+                                                                       /
                                                                output_pos
+   buf[cpos] = 32 + 8
 
 ----------------------------------------------------------------------------
 
@@ -3870,6 +3871,18 @@ buf     |  32 | c1  | c2  | len |    off    |  c3 |  c4 |  c5 |  c6 |  c7 |
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+# ¤É¤¦¤ä¤é¥Ð¥°¤Ç¤Ï¤Ê¤¤¤é¤·¤¤¡£3 * CHAR_BIT ¤È¤¤¤¦¤Î¤Ï¡¢1¥Ö¥í¥Ã¥¯¤¬
+# CHAR_BIT ¤Î¥¹¥í¥Ã¥È(8 ¤Ä¤Î¥¹¥í¥Ã¥È)¤ò»ý¤Á¡¢1 ¥Ö¥í¥Ã¥¯¤¬¤¹¤Ù¤Æ
+# <len,off> (3 bytes)¤Î¾ì¹ç¡¢ºÇÂç 3 bytes * 8 ¤È¤Ê¤ë¤³¤È¤ò¼¨¤·¤Æ¤¤¤ë¤è
+# ¤¦¤À¡£
+# CHAR_BIT ¤Ï¡¢buf[cpos] ¤Î¥Ó¥Ã¥È¿ô¤òɽ¤·¤Æ¤¤¤ë¡£
+#
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+#       3 * CHAR_BIT + 1
+# ¤È¤Ê¤ë¡£¤½¤¦¤¤¤¦°ÕÌ£¤Ç¤Ï¡¢
+#       if (output_pos > bufsiz - (3 * CHAR_BIT + 1)) {
+# ¤ÎÊý¤¬¤ï¤«¤ê¤ä¤¹¤¤¤è¤¦¤Ë»×¤¦¡£
+
 output_pos = 0 ¤È¤·¤Æ¤¤¤ë¤³¤È¤«¤é¤³¤Î»þÅÀ¤Î buf ¤ÎÃæ¿È¤¬¤¹¤Ù¤Æ 
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@@ -5035,6 +5048,64 @@ start[i] 
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+bit ¿ô¤ò¸º¤é¤¹Íýͳ¤ò¹Í¤¨¤Æ¤ß¤ë¡£É½°ú¤­¤Î¹Í¤¨Êý¤Ï¡¢
+
+       /\               a: 0
+      a /\              b: 10
+        b c             c: 11
+
+¤È¤¤¤¦ Huffman ÌڤˤĤ¤¤Æ¡¢
+
+     00: c_table[00] = a
+     01: c_table[01] = a
+     10: c_table[10] = b
+     11: c_table[11] = c
+
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+Éä¹æ¤ÎºÇÂçÃÍ¤Ï 65535 ¤Ç¤¢¤ë¤«¤é
+
+  unsigned short c_table[65535+1]; (unsigned short > NC-1)
+
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+
+      0: c_table[ 0=0] = a
+     10: c_table[10=2] = b
+     11: c_table[11=3] = c
+
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+¼ÂºÝ¤Î c_table[] ¤ÎÄêµÁ¤Ï¡¢
+
+  unsigned short c_table[4095+1];
+
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+¤Æ¤¤¤ë¡£¤½¤·¤Æ¡¢Ê£¹ç¸ì¤Ï¡¢0...NC ¤ÎÈϰϤǤ¢¤ë¤«¤é¡¢
+    c_table[¥Ó¥Ã¥ÈÎó] < NC
+¤Î¾ì¹ç¤Ï¡¢¤½¤Î¤Þ¤Þɽ°ú¤­¤Ç
+    c_table[¥Ó¥Ã¥ÈÎó] >= NC
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+
+       /\
+      a /\           ... ³¬ÁØ:1
+        b            ... ³¬ÁØ:2
+        :
+           /\
+          x  x       ... ³¬ÁØ:12
+
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+
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