merges r30280 from trunk into ruby_1_9_2.

--
	* io.c : add an extra byte to buffer for the specification of read
	  in Windows. see [ruby-core:33460] and r29980. and, we have to
	  discuss how to do this one byte.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_1_9_2@30321 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 34 insertions, 36 deletions

diff --git a/io.c b/io.c
index 474562a944..2b40b08f0f 100644
--- a/io.c
+++ b/io.c
@@ -1211,6 +1211,9 @@ io_fillbuf(rb_io_t *fptr)
         fptr->rbuf_len = 0;
         fptr->rbuf_capa = IO_RBUF_CAPA_FOR(fptr);
         fptr->rbuf = ALLOC_N(char, fptr->rbuf_capa);
+#ifdef _WIN32
+	fptr->rbuf.capa--;
+#endif
     }
     if (fptr->rbuf_len == 0) {
       retry:
@@ -1734,6 +1737,32 @@ io_shift_cbuf(rb_io_t *fptr, int len, VALUE *strp)
     return str;
 }
 
+static void
+io_setstrbuf(VALUE *str,long len)
+{
+#ifdef _WIN32
+    if (NIL_P(*str)) {
+	*str = rb_str_new(0, len+1);
+	rb_str_set_len(*str,len);
+    }
+    else {
+	StringValue(*str);
+	rb_str_modify(*str);
+	rb_str_resize(*str, len+1);
+	rb_str_set_len(*str,len);
+    }
+#else
+    if (NIL_P(*str)) {
+	*str = rb_str_new(0, len);
+    }
+    else {
+	StringValue(*str);
+	rb_str_modify(*str);
+	rb_str_resize(*str, len);
+    }
+#endif
+}
+
 static VALUE
 read_all(rb_io_t *fptr, long siz, VALUE str)
 {
@@ -1744,8 +1773,7 @@ read_all(rb_io_t *fptr, long siz, VALUE str)
     int cr;
 
     if (NEED_READCONV(fptr)) {
-        if (NIL_P(str)) str = rb_str_new(NULL, 0);
-        else rb_str_set_len(str, 0);
+	io_setstrbuf(&str,0);
         make_readconv(fptr, 0);
         while (1) {
             VALUE v;
@@ -1773,12 +1801,7 @@ read_all(rb_io_t *fptr, long siz, VALUE str)
     cr = 0;
 
     if (siz == 0) siz = BUFSIZ;
-    if (NIL_P(str)) {
-	str = rb_str_new(0, siz);
-    }
-    else {
-	rb_str_resize(str, siz);
-    }
+    io_setstrbuf(&str,siz);
     for (;;) {
 	READ_CHECK(fptr);
 	n = io_fread(str, bytes, fptr);
@@ -1831,14 +1854,7 @@ io_getpartial(int argc, VALUE *argv, VALUE io, int nonblock)
 	rb_raise(rb_eArgError, "negative length %ld given", len);
     }
 
-    if (NIL_P(str)) {
-	str = rb_str_new(0, len);
-    }
-    else {
-	StringValue(str);
-	rb_str_modify(str);
-        rb_str_resize(str, len);
-    }
+    io_setstrbuf(&str,len);
     OBJ_TAINT(str);
 
     GetOpenFile(io, fptr);
@@ -2157,10 +2173,6 @@ io_read(int argc, VALUE *argv, VALUE io)
     rb_scan_args(argc, argv, "02", &length, &str);
 
     if (NIL_P(length)) {
-	if (!NIL_P(str)){
-	    StringValue(str);
-	    rb_str_modify(str);
-	}
 	GetOpenFile(io, fptr);
 	rb_io_check_char_readable(fptr);
 	return read_all(fptr, remain_size(fptr), str);
@@ -2170,14 +2182,7 @@ io_read(int argc, VALUE *argv, VALUE io)
 	rb_raise(rb_eArgError, "negative length %ld given", len);
     }
 
-    if (NIL_P(str)) {
-	str = rb_str_new(0, len);
-    }
-    else {
-	StringValue(str);
-	rb_str_modify(str);
-	rb_str_resize(str,len);
-    }
+    io_setstrbuf(&str,len);
 
     GetOpenFile(io, fptr);
     rb_io_check_byte_readable(fptr);
@@ -3882,14 +3887,7 @@ rb_io_sysread(int argc, VALUE *argv, VALUE io)
     rb_scan_args(argc, argv, "11", &len, &str);
     ilen = NUM2LONG(len);
 
-    if (NIL_P(str)) {
-	str = rb_str_new(0, ilen);
-    }
-    else {
-	StringValue(str);
-	rb_str_modify(str);
-	rb_str_resize(str, ilen);
-    }
+    io_setstrbuf(&str,ilen);
     if (ilen == 0) return str;
 
     GetOpenFile(io, fptr);