From 4bceda1125242d365558d6c870215c8e2125e29a Mon Sep 17 00:00:00 2001
From: akr <akr@b2dd03c8-39d4-4d8f-98ff-823fe69b080e>
Date: Sat, 9 Aug 2008 07:35:28 +0000
Subject: [PATCH] * transcode_data.h (rb_transcoding): new fields: next_info
 and next_byte.

* transcode.c (transcode_restartable): save/restore next_info and
  next_byte.
  sync readlen and in_p when invalid.


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@18454 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
---
 ChangeLog        |  8 ++++++++
 transcode.c      | 33 +++++++++++++++++++++++----------
 transcode_data.h |  2 ++
 3 files changed, 33 insertions(+), 10 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 5bbc89be33..f16780a32c 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,11 @@
+Sat Aug  9 16:33:21 2008  Tanaka Akira  <akr@fsij.org>
+
+	* transcode_data.h (rb_transcoding): new fields: next_info and next_byte.
+
+	* transcode.c (transcode_restartable): save/restore next_info and
+	  next_byte.
+	  sync readlen and in_p when invalid.
+
 Sat Aug  9 15:10:15 2008  Tanaka Akira  <akr@fsij.org>
 
 	* transcode.c (transcode_restartable): my_transcoder argument removed.
diff --git a/transcode.c b/transcode.c
index c1323e3ac7..dd57f0809d 100644
--- a/transcode.c
+++ b/transcode.c
@@ -368,6 +368,8 @@ transcode_restartable(const unsigned char **in_pos, unsigned char **out_pos,
     unsigned char *out_p;
     int readlen;
     const BYTE_LOOKUP *next_table;
+    VALUE next_info;
+    unsigned char next_byte;
 
     unsigned char empty_buf;
     unsigned char *empty_ptr = &empty_buf;
@@ -386,6 +388,8 @@ transcode_restartable(const unsigned char **in_pos, unsigned char **out_pos,
     out_p = *out_pos;
     readlen = my_transcoding->readlen;
     next_table = my_transcoding->next_table;
+    next_info = my_transcoding->next_info;
+    next_byte = my_transcoding->next_byte;
 
 #define SUSPEND(ret, num) \
     do { \
@@ -399,6 +403,8 @@ transcode_restartable(const unsigned char **in_pos, unsigned char **out_pos,
         *out_pos = out_p; \
         my_transcoding->readlen = readlen; \
         my_transcoding->next_table = next_table; \
+        my_transcoding->next_info = next_info; \
+        my_transcoding->next_byte = next_byte; \
         return ret; \
         resume_label ## num:; \
     } while (0)
@@ -422,9 +428,6 @@ transcode_restartable(const unsigned char **in_pos, unsigned char **out_pos,
     }
 
     while (1) {
-        unsigned char next_byte;
-        VALUE next_info;
-
         if (in_stop <= in_p) {
             if (!(opt & PARTIAL_INPUT))
                 break;
@@ -460,7 +463,6 @@ transcode_restartable(const unsigned char **in_pos, unsigned char **out_pos,
             readlen++;
 	    next_table = (const BYTE_LOOKUP *)next_info;
 	    goto follow_byte;
-	    /* maybe rewrite the following cases to use fallthrough???? */
 	  case ZERObt: /* drop input */
 	    continue;
 	  case ONEbt:
@@ -509,21 +511,32 @@ transcode_restartable(const unsigned char **in_pos, unsigned char **out_pos,
             }
 	  case INVALID:
             {
+                int step;
                 if (readlen <= unitlen) {
                     while ((opt & PARTIAL_INPUT) && readlen + (in_stop - in_p) < unitlen) {
-                        readlen += in_stop - in_p;
+                        step = in_stop - in_p;
+                        readlen += step;
                         in_p = in_stop;
                         SUSPEND(transcode_ibuf_empty, 8);
                     }
-                    if (readlen + (in_stop - in_p) <= unitlen)
+                    if (readlen + (in_stop - in_p) <= unitlen) {
+                        step = in_stop - in_p;
+                        readlen += step;
                         in_p = in_stop;
-                    else
-                        in_p += unitlen - readlen;
+                    }
+                    else {
+                        step = unitlen - readlen;
+                        readlen = unitlen;
+                        in_p += step;
+                    }
                 }
                 else {
-                    /* xxx: possibly in_p is lesser than *in_pos
+                    /* xxx: step may be negative.
+                     * possibly in_p is lesser than *in_pos.
                      * caller may want to access readbuf.  */
-                    in_p += ((readlen - 1) / unitlen) * unitlen - readlen;
+                    step = ((readlen - 1) / unitlen) * unitlen - readlen;
+                    in_p += step;
+                    readlen += step;
                 }
                 goto invalid;
             }
diff --git a/transcode_data.h b/transcode_data.h
index 3801c38ec8..12e24e71eb 100644
--- a/transcode_data.h
+++ b/transcode_data.h
@@ -66,6 +66,8 @@ typedef struct rb_transcoding {
 
     int resume_position;
     const BYTE_LOOKUP *next_table;
+    VALUE next_info;
+    unsigned char next_byte;
     int readlen;
     union {
         unsigned char ary[8]; /* max_input <= sizeof(ary) */