From c9331864f847a78550da88a780a5981bd283a6c7 Mon Sep 17 00:00:00 2001
From: nobu <nobu@b2dd03c8-39d4-4d8f-98ff-823fe69b080e>
Date: Mon, 7 Jun 2010 21:04:56 +0000
Subject: [PATCH] * io.c (parse_mode_enc): set set_by_bom bit. 
 [ruby-core:30641]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@28199 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
---
 ChangeLog                 |  4 ++++
 io.c                      | 20 ++++++++++----------
 test/ruby/test_io_m17n.rb |  4 ++++
 3 files changed, 18 insertions(+), 10 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 1733d5023d..7a5a0b04bd 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+Tue Jun  8 06:04:49 2010  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* io.c (parse_mode_enc): set set_by_bom bit.  [ruby-core:30641]
+
 Sun Jun  6 22:37:11 2010  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* string.c (rb_str_buf_cat_escaped_char): get rid of buffer
diff --git a/io.c b/io.c
index b08561befa..d010f38374 100644
--- a/io.c
+++ b/io.c
@@ -4216,7 +4216,7 @@ rb_io_ext_int_to_encs(rb_encoding *ext, rb_encoding *intern, rb_encoding **enc,
 }
 
 static void
-parse_mode_enc(const char *estr, rb_encoding **enc_p, rb_encoding **enc2_p)
+parse_mode_enc(const char *estr, rb_encoding **enc_p, rb_encoding **enc2_p, int *fmode_p)
 {
     const char *p;
     char encname[ENCODING_MAXNAMELEN+1];
@@ -4232,6 +4232,7 @@ parse_mode_enc(const char *estr, rb_encoding **enc_p, rb_encoding **enc2_p)
 	    idx = -1;
 	else {
 	    if (io_encname_bom_p(estr, len)) {
+		if (fmode_p) *fmode_p |= FMODE_SETENC_BY_BOM;
 		estr += 4;
                 len -= 4;
             }
@@ -4244,6 +4245,7 @@ parse_mode_enc(const char *estr, rb_encoding **enc_p, rb_encoding **enc2_p)
     else {
 	long len = strlen(estr);
 	if (io_encname_bom_p(estr, len)) {
+	    if (fmode_p) *fmode_p |= FMODE_SETENC_BY_BOM;
 	    estr += 4;
             len -= 4;
 	    memcpy(encname, estr, len);
@@ -4288,7 +4290,7 @@ mode_enc(rb_io_t *fptr, const char *estr)
 {
     clear_codeconv(fptr);
 
-    parse_mode_enc(estr, &fptr->encs.enc, &fptr->encs.enc2);
+    parse_mode_enc(estr, &fptr->encs.enc, &fptr->encs.enc2, NULL);
 }
 
 static void
@@ -4301,7 +4303,7 @@ rb_io_mode_enc(rb_io_t *fptr, const char *modestr)
 }
 
 int
-rb_io_extract_encoding_option(VALUE opt, rb_encoding **enc_p, rb_encoding **enc2_p)
+rb_io_extract_encoding_option(VALUE opt, rb_encoding **enc_p, rb_encoding **enc2_p, int *fmode_p)
 {
     VALUE encoding=Qnil, extenc=Qundef, intenc=Qundef, tmp;
     int extracted = 0;
@@ -4351,7 +4353,7 @@ rb_io_extract_encoding_option(VALUE opt, rb_encoding **enc_p, rb_encoding **enc2
     }
     if (!NIL_P(encoding)) {
 	extracted = 1;
-	parse_mode_enc(StringValueCStr(encoding), enc_p, enc2_p);
+	parse_mode_enc(StringValueCStr(encoding), enc_p, enc2_p, fmode_p);
     }
     else if (extenc != Qundef || intenc != Qundef) {
         extracted = 1;
@@ -4426,9 +4428,7 @@ rb_io_extract_modeenc(VALUE *vmode_p, VALUE *vperm_p, VALUE opthash,
         p = strchr(p, ':');
         if (p) {
             has_enc = 1;
-            parse_mode_enc(p+1, &enc, &enc2);
-	    if (io_encname_bom_p(p+1, 0))
-		fmode |= FMODE_SETENC_BY_BOM;
+            parse_mode_enc(p+1, &enc, &enc2, &fmode);
         }
 	else {
 	    rb_encoding *e;
@@ -4474,7 +4474,7 @@ rb_io_extract_modeenc(VALUE *vmode_p, VALUE *vperm_p, VALUE opthash,
 	}
         ecflags = rb_econv_prepare_opts(opthash, &ecopts);
 
-        if (rb_io_extract_encoding_option(opthash, &enc, &enc2)) {
+        if (rb_io_extract_encoding_option(opthash, &enc, &enc2, &fmode)) {
             if (has_enc) {
                 rb_raise(rb_eArgError, "encoding specified twice");
             }
@@ -4700,7 +4700,7 @@ rb_file_open_internal(VALUE io, VALUE filename, const char *modestr)
     convconfig_t convconfig;
 
     if (p) {
-        parse_mode_enc(p+1, &convconfig.enc, &convconfig.enc2);
+        parse_mode_enc(p+1, &convconfig.enc, &convconfig.enc2, &fmode);
     }
     else {
 	rb_encoding *e;
@@ -7630,7 +7630,7 @@ io_encoding_set(rb_io_t *fptr, VALUE v1, VALUE v2, VALUE opt)
 	else {
 	    tmp = rb_check_string_type(v1);
 	    if (!NIL_P(tmp) && rb_enc_asciicompat(rb_enc_get(tmp))) {
-                parse_mode_enc(RSTRING_PTR(tmp), &enc, &enc2);
+                parse_mode_enc(RSTRING_PTR(tmp), &enc, &enc2, NULL);
                 ecflags = rb_econv_prepare_opts(opt, &ecopts);
 	    }
 	    else {
diff --git a/test/ruby/test_io_m17n.rb b/test/ruby/test_io_m17n.rb
index 7bdd8e9b0f..f2a0f19d16 100644
--- a/test/ruby/test_io_m17n.rb
+++ b/test/ruby/test_io_m17n.rb
@@ -1740,6 +1740,10 @@ EOT
         assert_equal(content[1].force_encoding("ascii-8bit"),
                      result.force_encoding("ascii-8bit"))
       end
+
+      bug3407 = '[ruby-core:30641]'
+      result = File.read('UTF-8-bom.txt', encoding: 'BOM|UTF-8')
+      assert_equal("a", result.force_encoding("ascii-8bit"), bug3407)
     }
   end