[PATCH v5 0/3] MR1199: xmllite/writer : Implement a few APIs

[David Kahurani (＠kahurani)]

Signed-off-by: David Kahurani

--
  v5: xmllite/writer: Implement WriteSurrogateCharEntity.
      xmllite/writer: Implement WriteRawChars.
      xmllite/writer: Implement WriteChars.

https://gitlab.winehq.org/wine/wine/-/merge_requests/1199

[PATCH v5 1/3] xmllite/writer: Implement WriteChars.

[David Kahurani]

From: David Kahurani

Signed-off-by: David Kahurani 
---
 dlls/xmllite/tests/writer.c | 126 +++++++++++++++++++++++++++
 dlls/xmllite/writer.c       | 165 +++++++++++++++++++-----------------
 2 files changed, 214 insertions(+), 77 deletions(-)

diff --git a/dlls/xmllite/tests/writer.c b/dlls/xmllite/tests/writer.c
index d15fe8b64df..0559a088be5 100644
--- a/dlls/xmllite/tests/writer.c
+++ b/dlls/xmllite/tests/writer.c
@@ -1497,6 +1497,15 @@ static void test_writer_state(void)
     check_writer_state(writer, WR_E_INVALIDACTION);
     IStream_Release(stream);

+    /* WriteChars */
+    stream = writer_set_output(writer);
+
+    hr = IXmlWriter_WriteChars(writer, L"a", 1);
+    ok(hr == WR_E_INVALIDACTION, "Unexpected hr %#lx.\n", hr);
+
+    check_writer_state(writer, WR_E_INVALIDACTION);
+
+    IStream_Release(stream);
     IXmlWriter_Release(writer);
 }

@@ -2123,6 +2132,122 @@ static void test_WriteString(void)
     IStream_Release(stream);
 }

+static void test_WriteChars(void)
+{
+    IXmlWriter *writer;
+    IStream *stream;
+    HRESULT hr;
+    static WCHAR raw[] = {'s', 'a', 'm', 0xd800, 0xdc00, 'p', 'l', 'e', 0};
+
+    hr = CreateXmlWriter(&IID_IXmlWriter, (void**)&writer, NULL);
+    ok(hr == S_OK, "Unexpected hr %#lx.\n", hr);
+
+    hr = IXmlWriter_WriteChars(writer, NULL, 0);
+    ok(hr == S_OK, "Unexpected hr %#lx.\n", hr);
+
+    hr = IXmlWriter_WriteChars(writer, NULL, 5);
+    ok(hr == E_INVALIDARG, "Unexpected hr %#lx.\n", hr);
+
+    hr = IXmlWriter_WriteChars(writer, L"", 0);
+    ok(hr == S_OK, "Unexpected hr %#lx.\n", hr);
+
+    hr = IXmlWriter_WriteChars(writer, L"", 5);
+    ok(hr == E_UNEXPECTED, "Unexpected hr %#lx.\n", hr);
+
+    stream = writer_set_output(writer);
+
+    writer_set_property(writer, XmlWriterProperty_OmitXmlDeclaration);
+
+    hr = IXmlWriter_WriteStartElement(writer, NULL, L"chars", NULL);
+    ok(hr == S_OK, "Unexpected hr %#lx.\n", hr);
+
+    hr = IXmlWriter_WriteChars(writer, NULL, 5);
+    ok(hr == E_INVALIDARG, "Unexpected hr %#lx.\n", hr);
+
+    hr = IXmlWriter_WriteChars(writer, L"<chars>", 20);
+    ok(hr == WC_E_XMLCHARACTER, "Unexpected hr %#lx.\n", hr);
+
+    hr = IXmlWriter_WriteChars(writer, L"<chars>", 7);
+    ok(hr == S_OK, "Unexpected hr %#lx.\n", hr);
+
+    hr = IXmlWriter_Flush(writer);
+    ok(hr == S_OK, "Unexpected hr %#lx.\n", hr);
+
+    CHECK_OUTPUT(stream,
+        "<chars>&lt;chars&gt;&lt;chars&gt;");
+    IStream_Release(stream);
+
+    stream = writer_set_output(writer);
+
+    hr = IXmlWriter_WriteStartElement(writer, NULL, L"chars", NULL);
+    ok(hr == S_OK, "Unexpected hr %#lx.\n", hr);
+
+    hr = IXmlWriter_WriteChars(writer, raw, 8);
+    ok(hr == S_OK, "Unexpected hr %#lx.\n", hr);
+
+    raw[3] = 0xdc00;
+    raw[4] = 0xd800;
+    hr = IXmlWriter_WriteChars(writer, raw, 8);
+    ok(hr == WR_E_INVALIDSURROGATEPAIR, "Unexpected hr %#lx.\n", hr);
+
+    hr = IXmlWriter_Flush(writer);
+    ok(hr == S_OK, "Unexpected hr %#lx.\n", hr);
+
+    CHECK_OUTPUT(stream, "<chars>sam\U00010000plesam");
+    IStream_Release(stream);
+
+    stream = writer_set_output(writer);
+
+    hr = IXmlWriter_WriteStartElement(writer, NULL, L"chars", NULL);
+    ok(hr == S_OK, "Unexpected hr %#lx.\n", hr);
+
+    hr = IXmlWriter_WriteChars(writer, NULL, 0);
+    ok(hr == S_OK, "Unexpected hr %#lx.\n", hr);
+
+    hr = IXmlWriter_WriteFullEndElement(writer);
+    ok(hr == S_OK, "Unexpected hr %#lx.\n", hr);
+
+    hr = IXmlWriter_Flush(writer);
+    ok(hr == S_OK, "Unexpected hr %#lx.\n", hr);
+
+    CHECK_OUTPUT(stream,
+        "<chars></chars>");
+    IStream_Release(stream);
+
+    stream = writer_set_output(writer);
+
+    hr = IXmlWriter_WriteStartElement(writer, NULL, L"chars", NULL);
+    ok(hr == S_OK, "Unexpected hr %#lx.\n", hr);
+
+    hr = IXmlWriter_WriteChars(writer, L"", 0);
+    ok(hr == S_OK, "Unexpected hr %#lx.\n", hr);
+
+    hr = IXmlWriter_Flush(writer);
+    ok(hr == S_OK, "Unexpected hr %#lx.\n", hr);
+
+    CHECK_OUTPUT(stream,
+        "<chars");
+
+    IStream_Release(stream);
+
+    stream = writer_set_output(writer);
+
+    hr = IXmlWriter_WriteStartElement(writer, NULL, L"c", NULL);
+    ok(hr == S_OK, "Unexpected hr %#lx.\n", hr);
+
+    hr = IXmlWriter_WriteChars(writer, L"", 5);
+    ok(hr == WC_E_XMLCHARACTER, "Unexpected hr %#lx.\n", hr);
+
+    hr = IXmlWriter_Flush(writer);
+    ok(hr == S_OK, "Unexpected hr %#lx.\n", hr);
+
+    CHECK_OUTPUT(stream,
+        "<c>");
+
+    IXmlWriter_Release(writer);
+    IStream_Release(stream);
+}
+
 static void test_WriteDocType(void)
 {
     static const struct
@@ -2650,6 +2775,7 @@ START_TEST(writer)
     test_WriteAttributeString();
     test_WriteFullEndElement();
     test_WriteCharEntity();
+    test_WriteChars();
     test_WriteString();
     test_WriteDocType();
     test_WriteWhitespace();
diff --git a/dlls/xmllite/writer.c b/dlls/xmllite/writer.c
index def165656ef..7f4b5b9022f 100644
--- a/dlls/xmllite/writer.c
+++ b/dlls/xmllite/writer.c
@@ -1104,28 +1104,110 @@ static HRESULT WINAPI xmlwriter_WriteCharEntity(IXmlWriter *iface, WCHAR ch)
     return S_OK;
 }

-static HRESULT WINAPI xmlwriter_WriteChars(IXmlWriter *iface, const WCHAR *pwch, UINT cwch)
+static HRESULT writer_get_next_write_count(const WCHAR *str, unsigned int length, unsigned int *count)
 {
-    xmlwriter *This = impl_from_IXmlWriter(iface);
+    if (!is_char(*str)) return WC_E_XMLCHARACTER;

-    FIXME("%p %s %d\n", This, wine_dbgstr_w(pwch), cwch);
+    if (IS_HIGH_SURROGATE(*str))
+    {
+        if (length < 2 || !IS_LOW_SURROGATE(*(str + 1)))
+            return WR_E_INVALIDSURROGATEPAIR;

-    switch (This->state)
+        *count = 2;
+    }
+    else if (IS_LOW_SURROGATE(*str))
+        return WR_E_INVALIDSURROGATEPAIR;
+    else
+        *count = 1;
+
+    return S_OK;
+}
+
+static HRESULT write_escaped_char(xmlwriter *writer, const WCHAR *string, unsigned int count)
+{
+    HRESULT hr;
+
+    switch (*string)
+    {
+       case '<':
+           hr = write_output_buffer(writer->output, L"&lt;", 4);
+           break;
+       case '&':
+           hr = write_output_buffer(writer->output, L"&amp;", 5);
+           break;
+       case '>':
+           hr = write_output_buffer(writer->output, L"&gt;", 4);
+           break;
+       default:
+           hr = write_output_buffer(writer->output, string, count);
+    }
+
+    return hr;
+}
+
+static HRESULT write_escaped_string(xmlwriter *writer, const WCHAR *string, unsigned int length)
+{
+    unsigned int count;
+    HRESULT hr = S_OK;
+
+    if (length == ~0u)
+    {
+        while (*string)
+        {
+            if (FAILED(hr = writer_get_next_write_count(string, ~0u, &count))) return hr;
+            if (FAILED(hr = write_escaped_char(writer, string, count))) return hr;
+
+            string += count;
+        }
+    }
+    else
+    {
+        while (length)
+        {
+            if (FAILED(hr = writer_get_next_write_count(string, length, &count))) return hr;
+            if (FAILED(hr = write_escaped_char(writer, string, count))) return hr;
+
+            string += count;
+            length -= count;
+        }
+    }
+
+    return hr;
+}
+
+static HRESULT WINAPI xmlwriter_WriteChars(IXmlWriter *iface, const WCHAR *characters, UINT count)
+{
+    xmlwriter *writer = impl_from_IXmlWriter(iface);
+
+    TRACE("%p, %s, %d.\n", iface, debugstr_wn(characters, count), count);
+
+    if ((characters == NULL && count != 0))
+        return E_INVALIDARG;
+
+    if (count == 0)
+        return S_OK;
+
+    switch (writer->state)
     {
     case XmlWriterState_Initial:
         return E_UNEXPECTED;
     case XmlWriterState_InvalidEncoding:
         return MX_E_ENCODING;
+    case XmlWriterState_ElemStarted:
+	writer_close_starttag(writer);
+	break;
+    case XmlWriterState_Ready:
     case XmlWriterState_DocClosed:
+        writer->state = XmlWriterState_DocClosed;
         return WR_E_INVALIDACTION;
     default:
         ;
     }

-    return E_NOTIMPL;
+    writer->textnode = 1;
+    return write_escaped_string(writer, characters, count);
 }

-
 static HRESULT WINAPI xmlwriter_WriteComment(IXmlWriter *iface, LPCWSTR comment)
 {
     xmlwriter *This = impl_from_IXmlWriter(iface);
@@ -1684,25 +1766,6 @@ static HRESULT WINAPI xmlwriter_WriteQualifiedName(IXmlWriter *iface, LPCWSTR pw
     return E_NOTIMPL;
 }

-static HRESULT writer_get_next_write_count(const WCHAR *str, unsigned int length, unsigned int *count)
-{
-    if (!is_char(*str)) return WC_E_XMLCHARACTER;
-
-    if (IS_HIGH_SURROGATE(*str))
-    {
-        if (length < 2 || !IS_LOW_SURROGATE(*(str + 1)))
-            return WR_E_INVALIDSURROGATEPAIR;
-
-        *count = 2;
-    }
-    else if (IS_LOW_SURROGATE(*str))
-        return WR_E_INVALIDSURROGATEPAIR;
-    else
-        *count = 1;
-
-    return S_OK;
-}
-
 static HRESULT WINAPI xmlwriter_WriteRaw(IXmlWriter *iface, LPCWSTR data)
 {
     xmlwriter *This = impl_from_IXmlWriter(iface);
@@ -1862,58 +1925,6 @@ static HRESULT WINAPI xmlwriter_WriteStartElement(IXmlWriter *iface, LPCWSTR pre
     return S_OK;
 }

-static HRESULT write_escaped_char(xmlwriter *writer, const WCHAR *string, unsigned int count)
-{
-    HRESULT hr;
-
-    switch (*string)
-    {
-       case '<':
-           hr = write_output_buffer(writer->output, L"&lt;", 4);
-           break;
-       case '&':
-           hr = write_output_buffer(writer->output, L"&amp;", 5);
-           break;
-       case '>':
-           hr = write_output_buffer(writer->output, L"&gt;", 4);
-           break;
-       default:
-           hr = write_output_buffer(writer->output, string, count);
-    }
-
-    return hr;
-}
-
-static HRESULT write_escaped_string(xmlwriter *writer, const WCHAR *string, unsigned int length)
-{
-    unsigned int count;
-    HRESULT hr = S_OK;
-
-    if (length == ~0u)
-    {
-        while (*string)
-        {
-            if (FAILED(hr = writer_get_next_write_count(string, ~0u, &count))) return hr;
-            if (FAILED(hr = write_escaped_char(writer, string, count))) return hr;
-
-            string += count;
-        }
-    }
-    else
-    {
-        while (length)
-        {
-            if (FAILED(hr = writer_get_next_write_count(string, length, &count))) return hr;
-            if (FAILED(hr = write_escaped_char(writer, string, count))) return hr;
-
-            string += count;
-            length -= count;
-        }
-    }
-
-    return hr;
-}
-
 static HRESULT WINAPI xmlwriter_WriteString(IXmlWriter *iface, const WCHAR *string)
 {
     xmlwriter *This = impl_from_IXmlWriter(iface);

[PATCH v5 2/3] xmllite/writer: Implement WriteRawChars.

[David Kahurani]

From: David Kahurani

Signed-off-by: David Kahurani 
---
 dlls/xmllite/tests/writer.c | 101 ++++++++++++++++++++++++++++++++++++
 dlls/xmllite/writer.c       |  32 ++++++++++--
 2 files changed, 128 insertions(+), 5 deletions(-)

diff --git a/dlls/xmllite/tests/writer.c b/dlls/xmllite/tests/writer.c
index 0559a088be5..377f66d2bd2 100644
--- a/dlls/xmllite/tests/writer.c
+++ b/dlls/xmllite/tests/writer.c
@@ -1903,6 +1903,106 @@ static void test_WriteCharEntity(void)
     IStream_Release(stream);
 }

+static void test_WriteRawChars(void)
+{
+    IXmlWriter *writer;
+    IStream *stream;
+    HRESULT hr;
+    static WCHAR surrogates[] = {0xd800, 0xdc00, 0};
+
+    hr = CreateXmlWriter(&IID_IXmlWriter, (void**)&writer, NULL);
+    ok(hr == S_OK, "Unexpected hr %#lx.\n", hr);
+
+    hr = IXmlWriter_WriteRawChars(writer, NULL, 0);
+    ok(hr == S_OK, "Unexpected hr %#lx.\n", hr);
+
+    hr = IXmlWriter_WriteRawChars(writer, L"", 0);
+    ok(hr == S_OK, "Unexpected hr %#lx.\n", hr);
+
+    hr = IXmlWriter_WriteRawChars(writer, NULL, 5);
+    ok(hr == E_INVALIDARG, "Unexpected hr %#lx.\n", hr);
+
+    hr = IXmlWriter_WriteRawChars(writer, L"", 6);
+    ok(hr == E_UNEXPECTED, "Unexpected hr %#lx.\n", hr);
+
+    stream = writer_set_output(writer);
+
+    writer_set_property(writer, XmlWriterProperty_OmitXmlDeclaration);
+
+    hr = IXmlWriter_WriteStartElement(writer, NULL, L"sub", NULL);
+    ok(hr == S_OK, "Unexpected hr %#lx.\n", hr);
+
+    hr = IXmlWriter_WriteRawChars(writer, L"<rawChars>", 5);
+    ok(hr == S_OK, "Unexpected hr %#lx.\n", hr);
+
+    hr = IXmlWriter_Flush(writer);
+    ok(hr == S_OK, "Unexpected hr %#lx.\n", hr);
+
+    CHECK_OUTPUT(stream, "<sub><rawC");
+    IStream_Release(stream);
+
+    stream = writer_set_output(writer);
+
+    hr = IXmlWriter_WriteStartElement(writer, NULL, L"sub", NULL);
+    ok(hr == S_OK, "Unexpected hr %#lx.\n", hr);
+
+    hr = IXmlWriter_WriteRawChars(writer, L"<;;>", 10);
+    ok(hr == WC_E_XMLCHARACTER, "Unexpected hr %#lx.\n", hr);
+
+    hr = IXmlWriter_Flush(writer);
+    ok(hr == S_OK, "Unexpected hr %#lx.\n", hr);
+
+    CHECK_OUTPUT(stream, "<sub><;;>");
+    IStream_Release(stream);
+
+    stream = writer_set_output(writer);
+
+    hr = IXmlWriter_WriteStartElement(writer, NULL, L"sub", NULL);
+    ok(hr == S_OK, "Unexpected hr %#lx.\n", hr);
+
+    hr = IXmlWriter_WriteRawChars(writer, surrogates, 1);
+    ok(hr == WR_E_INVALIDSURROGATEPAIR, "Unexpected hr %#lx.\n", hr);
+
+    hr = IXmlWriter_WriteRawChars(writer, surrogates, 2);
+    ok(hr == S_OK, "Unexpected hr %#lx.\n", hr);
+
+    hr = IXmlWriter_Flush(writer);
+    ok(hr == S_OK, "Unexpected hr %#lx.\n", hr);
+
+    CHECK_OUTPUT(stream, "<sub>\U00010000");
+    IStream_Release(stream);
+
+    stream = writer_set_output(writer);
+
+    hr = IXmlWriter_WriteStartElement(writer, NULL, L"sub", NULL);
+    ok(hr == S_OK, "Unexpected hr %#lx.\n", hr);
+
+    hr = IXmlWriter_WriteRawChars(writer, L"", 5);
+    ok(hr == WC_E_XMLCHARACTER, "Unexpected hr %#lx.\n", hr);
+
+    hr = IXmlWriter_Flush(writer);
+    ok(hr == S_OK, "Unexpected hr %#lx.\n", hr);
+
+    CHECK_OUTPUT(stream, "<sub>");
+    IStream_Release(stream);
+
+    stream = writer_set_output(writer);
+
+    hr = IXmlWriter_WriteStartElement(writer, NULL, L"sub", NULL);
+    ok(hr == S_OK, "Unexpected hr %#lx.\n", hr);
+
+    hr = IXmlWriter_WriteRawChars(writer, L"", 0);
+    ok(hr == S_OK, "Unexpected hr %#lx.\n", hr);
+
+    hr = IXmlWriter_Flush(writer);
+    ok(hr == S_OK, "Unexpected hr %#lx.\n", hr);
+
+    CHECK_OUTPUT(stream, "<sub");
+
+    IXmlWriter_Release(writer);
+    IStream_Release(stream);
+}
+
 static void test_WriteString(void)
 {
     static const WCHAR surrogates[] = {0xd800, 0xdc00, 'x', 'y', '\0'};
@@ -2776,6 +2876,7 @@ START_TEST(writer)
     test_WriteFullEndElement();
     test_WriteCharEntity();
     test_WriteChars();
+    test_WriteRawChars();
     test_WriteString();
     test_WriteDocType();
     test_WriteWhitespace();
diff --git a/dlls/xmllite/writer.c b/dlls/xmllite/writer.c
index 7f4b5b9022f..fd4e5779650 100644
--- a/dlls/xmllite/writer.c
+++ b/dlls/xmllite/writer.c
@@ -1808,13 +1808,21 @@ static HRESULT WINAPI xmlwriter_WriteRaw(IXmlWriter *iface, LPCWSTR data)
     return hr;
 }

-static HRESULT WINAPI xmlwriter_WriteRawChars(IXmlWriter *iface,  const WCHAR *pwch, UINT cwch)
+static HRESULT WINAPI xmlwriter_WriteRawChars(IXmlWriter *iface,  const WCHAR *characters, UINT count)
 {
-    xmlwriter *This = impl_from_IXmlWriter(iface);
+    xmlwriter *writer = impl_from_IXmlWriter(iface);
+    HRESULT hr = S_OK;
+    unsigned int written;

-    FIXME("%p %s %d\n", This, wine_dbgstr_w(pwch), cwch);
+    TRACE("%p, %s, %d.\n", iface, debugstr_wn(characters, count), count);

-    switch (This->state)
+    if ((characters == NULL && count != 0))
+        return E_INVALIDARG;
+
+    if (count == 0)
+        return S_OK;
+
+    switch (writer->state)
     {
     case XmlWriterState_Initial:
         return E_UNEXPECTED;
@@ -1822,11 +1830,25 @@ static HRESULT WINAPI xmlwriter_WriteRawChars(IXmlWriter *iface,  const WCHAR *p
         return MX_E_ENCODING;
     case XmlWriterState_DocClosed:
         return WR_E_INVALIDACTION;
+    case XmlWriterState_Ready:
+        write_xmldecl(writer, XmlStandalone_Omit);
+	break;
+    case XmlWriterState_ElemStarted:
+	writer_close_starttag(writer);
     default:
         ;
     }

-    return E_NOTIMPL;
+    while (count)
+    {
+        if (FAILED(hr = writer_get_next_write_count(characters, count, &written))) return hr;
+        if (FAILED(hr = write_output_buffer(writer->output, characters, written))) return hr;
+
+        characters += written;
+        count -= written;
+    }
+
+    return hr;
 }

static HRESULT WINAPI xmlwriter_WriteStartDocument(IXmlWriter *iface, XmlStandalone standalone)

[PATCH v5 3/3] xmllite/writer: Implement WriteSurrogateCharEntity.

[David Kahurani]

From: David Kahurani

Signed-off-by: David Kahurani 
---
 dlls/xmllite/tests/writer.c | 58 +++++++++++++++++++++++++++++++++++--
 dlls/xmllite/writer.c       | 30 +++++++++++++++++--
 2 files changed, 83 insertions(+), 5 deletions(-)

diff --git a/dlls/xmllite/tests/writer.c b/dlls/xmllite/tests/writer.c
index 377f66d2bd2..adcc33d7143 100644
--- a/dlls/xmllite/tests/writer.c
+++ b/dlls/xmllite/tests/writer.c
@@ -138,6 +138,8 @@ static void check_writer_state(IXmlWriter *writer, HRESULT exp_hr)
 {
     IXmlReader *reader;
     HRESULT hr;
+    WCHAR low = 0xdcef;
+    WCHAR high = 0xdaff;

hr = CreateXmlReader(&IID_IXmlReader, (void **)&reader, NULL);
     ok(hr == S_OK, "Unexpected hr %#lx.\n", hr);
@@ -217,7 +219,8 @@ static void check_writer_state(IXmlWriter *writer, HRESULT exp_hr)
     hr = IXmlWriter_WriteString(writer, L"a");
     ok(hr == exp_hr, "Unexpected hr %#lx, expected %#lx.\n", hr, exp_hr);

-    /* FIXME: add WriteSurrogateCharEntity */
+    hr = IXmlWriter_WriteSurrogateCharEntity(writer, low, high);
+    ok(hr == exp_hr, "Unexpected hr %#lx, expected %#lx.\n", hr, exp_hr);

hr = IXmlWriter_WriteWhitespace(writer, L" ");
     ok(hr == exp_hr, "Unexpected hr %#lx, expected %#lx.\n", hr, exp_hr);
@@ -372,6 +375,8 @@ static void test_invalid_output_encoding(IXmlWriter *writer, IUnknown *output)
 {
     IXmlReader *reader;
     HRESULT hr;
+    WCHAR low = 0xdcef;
+    WCHAR high = 0xdaff;

hr = CreateXmlReader(&IID_IXmlReader, (void **)&reader, NULL);
     ok(hr == S_OK, "Unexpected hr %#lx.\n", hr);
@@ -448,7 +453,8 @@ static void test_invalid_output_encoding(IXmlWriter *writer, IUnknown *output)
     hr = IXmlWriter_WriteString(writer, L"a");
     ok(hr == MX_E_ENCODING, "Unexpected hr %#lx.\n", hr);

-    /* TODO: WriteSurrogateCharEntity */
+    hr = IXmlWriter_WriteSurrogateCharEntity(writer, low, high);
+    ok(hr == MX_E_ENCODING, "Unexpected hr %#lx.\n", hr);

hr = IXmlWriter_WriteWhitespace(writer, L" ");
     ok(hr == MX_E_ENCODING, "Unexpected hr %#lx.\n", hr);
@@ -2003,6 +2009,53 @@ static void test_WriteRawChars(void)
     IStream_Release(stream);
 }

+static void test_WriteSurrogateCharEntity(void)
+{
+    IXmlWriter *writer;
+    IStream *stream;
+    HRESULT hr;
+    WCHAR low = 0xdcef;
+    WCHAR high = 0xdaff;
+
+    hr = CreateXmlWriter(&IID_IXmlWriter, (void**)&writer, NULL);
+    ok(hr == S_OK, "Unexpected hr %#lx.\n", hr);
+
+    hr = IXmlWriter_WriteSurrogateCharEntity(writer, high, low);
+    ok(hr == WC_E_XMLCHARACTER, "Unexpected hr %#lx.\n", hr);
+
+    stream = writer_set_output(writer);
+
+    writer_set_property(writer, XmlWriterProperty_OmitXmlDeclaration);
+
+    hr = IXmlWriter_WriteStartDocument(writer, XmlStandalone_Omit);
+    ok(hr == S_OK, "Unexpected hr %#lx.\n", hr);
+
+    hr = IXmlWriter_WriteStartElement(writer, NULL, L"root", NULL);
+    ok(hr == S_OK, "Unexpected hr %#lx.\n", hr);
+
+    hr = IXmlWriter_WriteSurrogateCharEntity(writer, high, low);
+    ok(hr == WC_E_XMLCHARACTER, "Unexpected hr %#lx.\n", hr);
+
+    hr = IXmlWriter_Flush(writer);
+    ok(hr == S_OK, "Unexpected hr %#lx.\n", hr);
+
+    CHECK_OUTPUT(stream, "<root");
+
+    hr = IXmlWriter_WriteSurrogateCharEntity(writer, low, high);
+    ok(hr == S_OK, "Unexpected hr %#lx.\n", hr);
+
+    hr = IXmlWriter_WriteFullEndElement(writer);
+    ok(hr == S_OK, "Unexpected hr %#lx.\n", hr);
+
+    hr = IXmlWriter_Flush(writer);
+    ok(hr == S_OK, "Unexpected hr %#lx.\n", hr);
+
+    CHECK_OUTPUT(stream, "<root>&#xCFCEF;</root>");
+
+    IXmlWriter_Release(writer);
+    IStream_Release(stream);
+}
+
 static void test_WriteString(void)
 {
     static const WCHAR surrogates[] = {0xd800, 0xdc00, 'x', 'y', '\0'};
@@ -2877,6 +2930,7 @@ START_TEST(writer)
     test_WriteCharEntity();
     test_WriteChars();
     test_WriteRawChars();
+    test_WriteSurrogateCharEntity();
     test_WriteString();
     test_WriteDocType();
     test_WriteWhitespace();
diff --git a/dlls/xmllite/writer.c b/dlls/xmllite/writer.c
index fd4e5779650..f63208a02fb 100644
--- a/dlls/xmllite/writer.c
+++ b/dlls/xmllite/writer.c
@@ -1979,11 +1979,35 @@ static HRESULT WINAPI xmlwriter_WriteString(IXmlWriter *iface, const WCHAR *stri

static HRESULT WINAPI xmlwriter_WriteSurrogateCharEntity(IXmlWriter *iface, WCHAR wchLow, WCHAR wchHigh)
 {
-    xmlwriter *This = impl_from_IXmlWriter(iface);
+    xmlwriter *writer = impl_from_IXmlWriter(iface);
+    int codepoint;
+    WCHAR bufW[16];

-    FIXME("%p %d %d\n", This, wchLow, wchHigh);
+    TRACE("%p, %d, %d.\n", iface, wchLow, wchHigh);

-    return E_NOTIMPL;
+    if (!IS_SURROGATE_PAIR(wchHigh, wchLow))
+        return WC_E_XMLCHARACTER;
+
+    switch(writer->state)
+    {
+    case XmlWriterState_Initial:
+        return E_UNEXPECTED;
+    case XmlWriterState_InvalidEncoding:
+	return MX_E_ENCODING;
+    case XmlWriterState_ElemStarted:
+	writer_close_starttag(writer);
+	break;
+    case XmlWriterState_DocClosed:
+	return WR_E_INVALIDACTION;
+    default:
+	;
+    }
+
+    codepoint = ((wchHigh - 0xd800) * 0x400) + (wchLow - 0xdc00) + 0x10000;
+    swprintf(bufW, ARRAY_SIZE(bufW), L"&#x%X;", codepoint);
+    write_output_buffer(writer->output, bufW, -1);
+
+    return S_OK;
 }

static HRESULT WINAPI xmlwriter_WriteWhitespace(IXmlWriter *iface, LPCWSTR text)