[Backport] Roll libxml to 7279d236

This patch also adds --allow-empty to the git commit command for windows
in the roll.py script since there are usually no changes for windows.
libxslt's roll.py already does this for windows.

Backport review link:
https://chromium-review.googlesource.com/c/chromium/src/+/2866731

Bug: 934413
Change-Id: If055dabe61e5be77e4cf649f285f9b20c91ec3c6
Reviewed-by: Allan Sandfeld Jensen <allan.jensen@qt.io>

18 files changed, 536 insertions, 286 deletions

diff --git a/chromium/third_party/libxml/README.chromium b/chromium/third_party/libxml/README.chromium
index ade5386d6ff..9dceea6c310 100644
--- a/chromium/third_party/libxml/README.chromium
+++ b/chromium/third_party/libxml/README.chromium
@@ -1,6 +1,6 @@
 Name: libxml
 URL: http://xmlsoft.org
-Version: f93ca3e140a371b26366f747a408588c631e0fd1
+Version: 7279d236364739a05657a8a614c15990eb08d0c6
 CPEPrefix: cpe:/a:xmlsoft:libxml2:2.9.9
 License: MIT
 License File: src/Copyright
diff --git a/chromium/third_party/libxml/chromium/roll.py b/chromium/third_party/libxml/chromium/roll.py
index 1c5f58a4f76..2908cc58c9b 100755
--- a/chromium/third_party/libxml/chromium/roll.py
+++ b/chromium/third_party/libxml/chromium/roll.py
@@ -404,7 +404,7 @@ def roll_libxml_win32(src_path):
             shutil.move('../include/libxml/xmlversion.h',
                         '../../win32/include/libxml/xmlversion.h')
             git('add', '../../win32/include/libxml/xmlversion.h')
-            git('commit', '-m', 'Windows')
+            git('commit', '--allow-empty', '-m', 'Windows')
             git('clean', '-f')
     print('Now push to Mac and run steps there.')
 
diff --git a/chromium/third_party/libxml/mac/config.h b/chromium/third_party/libxml/mac/config.h
index 563202e18d8..ac184956426 100644
--- a/chromium/third_party/libxml/mac/config.h
+++ b/chromium/third_party/libxml/mac/config.h
@@ -91,9 +91,6 @@
 /* Define to 1 if you have the <math.h> header file. */
 #define HAVE_MATH_H 1
 
-/* Define to 1 if you have the <memory.h> header file. */
-#define HAVE_MEMORY_H 1
-
 /* Define to 1 if you have the `mmap' function. */
 #define HAVE_MMAP 1
 
@@ -165,6 +162,9 @@
 /* Define to 1 if you have the <stdint.h> header file. */
 #define HAVE_STDINT_H 1
 
+/* Define to 1 if you have the <stdio.h> header file. */
+#define HAVE_STDIO_H 1
+
 /* Define to 1 if you have the <stdlib.h> header file. */
 #define HAVE_STDLIB_H 1
 
@@ -263,7 +263,9 @@
 /* Type cast for the send() function 2nd arg */
 #define SEND_ARG2_CAST /**/
 
-/* Define to 1 if you have the ANSI C header files. */
+/* Define to 1 if all of the C90 standard headers exist (not just the ones
+   required in a freestanding environment). This macro is provided for
+   backward compatibility; new code need not use it. */
 #define STDC_HEADERS 1
 
 /* Support for IPv6 */
diff --git a/chromium/third_party/libxml/src/CMakeLists.txt b/chromium/third_party/libxml/src/CMakeLists.txt
index da0e5a913e6..a437717ba35 100644
--- a/chromium/third_party/libxml/src/CMakeLists.txt
+++ b/chromium/third_party/libxml/src/CMakeLists.txt
@@ -1,6 +1,6 @@
 cmake_minimum_required(VERSION 3.15)
 
-project(libxml2 C)
+project(libxml2 VERSION 2.9.10 LANGUAGES C)
 
 include(CheckCSourceCompiles)
 include(CheckFunctionExists)
@@ -11,16 +11,6 @@ include(CheckSymbolExists)
 include(CMakePackageConfigHelpers)
 include(GNUInstallDirs)
 
-set(LIBXML_MAJOR_VERSION 2)
-set(LIBXML_MINOR_VERSION 9)
-set(LIBXML_MICRO_VERSION 10)
-
-set(VERSION "${LIBXML_MAJOR_VERSION}.${LIBXML_MINOR_VERSION}.${LIBXML_MICRO_VERSION}")
-set(LIBXML_VERSION ${LIBXML_MAJOR_VERSION}0${LIBXML_MINOR_VERSION}0${LIBXML_MICRO_VERSION})
-set(LIBXML_VERSION_STRING "${LIBXML_VERSION}")
-set(LIBXML_VERSION_EXTRA "")
-set(LIBXML_VERSION_NUMBER ${LIBXML_VERSION})
-
 option(BUILD_SHARED_LIBS "Build shared libraries" ON)
 set(LIBXML2_WITH_AUTOMATA ON)
 option(LIBXML2_WITH_C14N "Add the Canonicalization support" ON)
@@ -105,6 +95,16 @@ foreach(VARIABLE IN ITEMS WITH_AUTOMATA WITH_C14N WITH_CATALOG WITH_DEBUG WITH_D
 	endif()
 endforeach()
 
+set(LIBXML_MAJOR_VERSION ${PROJECT_VERSION_MAJOR})
+set(LIBXML_MINOR_VERSION ${PROJECT_VERSION_MINOR})
+set(LIBXML_MICRO_VERSION ${PROJECT_VERSION_PATCH})
+
+set(VERSION "${LIBXML_MAJOR_VERSION}.${LIBXML_MINOR_VERSION}.${LIBXML_MICRO_VERSION}")
+set(LIBXML_VERSION ${LIBXML_MAJOR_VERSION}0${LIBXML_MINOR_VERSION}0${LIBXML_MICRO_VERSION})
+set(LIBXML_VERSION_STRING "${LIBXML_VERSION}")
+set(LIBXML_VERSION_EXTRA "")
+set(LIBXML_VERSION_NUMBER ${LIBXML_VERSION})
+
 set(MODULE_EXTENSION "${CMAKE_SHARED_LIBRARY_SUFFIX}")
 
 set(PACKAGE "libxml2")
@@ -493,10 +493,10 @@ set_target_properties(
 	OUTPUT_NAME xml2
 	POSITION_INDEPENDENT_CODE ON
 	PREFIX lib
-	VERSION ${VERSION}
+	VERSION ${PROJECT_VERSION}
 )
 
-if(WIN32)
+if(MSVC)
 	if(BUILD_SHARED_LIBS)
 		set_target_properties(
 			LibXml2
@@ -637,7 +637,7 @@ if(LIBXML2_WITH_PYTHON)
 		IMPORT_PREFIX lib
 		OUTPUT_NAME xml2mod
 		PREFIX lib
-		VERSION ${VERSION}
+		VERSION ${PROJECT_VERSION}
 	)
 	install(
 		TARGETS	LibXml2Mod
@@ -659,30 +659,30 @@ install(DIRECTORY doc/ DESTINATION ${CMAKE_INSTALL_DATADIR}/doc/libxml2 COMPONEN
 
 configure_package_config_file(
 	libxml2-config.cmake.cmake.in libxml2-config.cmake
-	INSTALL_DESTINATION ${CMAKE_INSTALL_LIBDIR}/cmake/libxml2-${VERSION}
+	INSTALL_DESTINATION ${CMAKE_INSTALL_LIBDIR}/cmake/libxml2-${PROJECT_VERSION}
 )
 
 install(
 	FILES ${CMAKE_CURRENT_BINARY_DIR}/libxml2-config.cmake
-	DESTINATION ${CMAKE_INSTALL_LIBDIR}/cmake/libxml2-${VERSION}
+	DESTINATION ${CMAKE_INSTALL_LIBDIR}/cmake/libxml2-${PROJECT_VERSION}
 	COMPONENT development
 )
 
 write_basic_package_version_file(
 	${CMAKE_CURRENT_BINARY_DIR}/libxml2-config-version.cmake
-	VERSION ${VERSION}
+	VERSION ${PROJECT_VERSION}
 	COMPATIBILITY ExactVersion
 )
 
 install(
 	FILES ${CMAKE_CURRENT_BINARY_DIR}/libxml2-config-version.cmake
-	DESTINATION ${CMAKE_INSTALL_LIBDIR}/cmake/libxml2-${VERSION}
+	DESTINATION ${CMAKE_INSTALL_LIBDIR}/cmake/libxml2-${PROJECT_VERSION}
 	COMPONENT development
 )
 
 install(
 	EXPORT LibXml2
-	DESTINATION ${CMAKE_INSTALL_LIBDIR}/cmake/libxml2-${VERSION}
+	DESTINATION ${CMAKE_INSTALL_LIBDIR}/cmake/libxml2-${PROJECT_VERSION}
 	NAMESPACE LibXml2::
 	FILE libxml2-export.cmake
 	COMPONENT development
diff --git a/chromium/third_party/libxml/src/HTMLparser.c b/chromium/third_party/libxml/src/HTMLparser.c
index 2877f4b71b9..b56363a3a03 100644
--- a/chromium/third_party/libxml/src/HTMLparser.c
+++ b/chromium/third_party/libxml/src/HTMLparser.c
@@ -457,7 +457,12 @@ htmlCurrentChar(xmlParserCtxtPtr ctxt, int *len) {
             ctxt->input->encoding = guess;
             handler = xmlFindCharEncodingHandler((const char *) guess);
             if (handler != NULL) {
-                xmlSwitchToEncoding(ctxt, handler);
+                /*
+                 * Don't use UTF-8 encoder which isn't required and
+                 * can produce invalid UTF-8.
+                 */
+                if (!xmlStrEqual(BAD_CAST handler->name, BAD_CAST "UTF-8"))
+                    xmlSwitchToEncoding(ctxt, handler);
             } else {
                 htmlParseErr(ctxt, XML_ERR_INVALID_ENCODING,
                              "Unsupported encoding %s", guess, NULL);
@@ -570,7 +575,16 @@ encoding_error:
 		     BAD_CAST buffer, NULL);
     }
 
-    ctxt->charset = XML_CHAR_ENCODING_8859_1;
+    /*
+     * Don't switch encodings twice. Note that if there's an encoder, we
+     * shouldn't receive invalid UTF-8 anyway.
+     *
+     * Note that if ctxt->input->buf == NULL, switching encodings is
+     * impossible, see Gitlab issue #34.
+     */
+    if ((ctxt->input->buf != NULL) &&
+        (ctxt->input->buf->encoder == NULL))
+        xmlSwitchEncoding(ctxt, XML_CHAR_ENCODING_8859_1);
     *len = 1;
     return((int) *ctxt->input->cur);
 }
@@ -1058,102 +1072,266 @@ html40ElementTable[] = {
 }
 };
 
+typedef struct {
+    const char *oldTag;
+    const char *newTag;
+} htmlStartCloseEntry;
+
 /*
  * start tags that imply the end of current element
  */
-static const char * const htmlStartClose[] = {
-"form",		"form", "p", "hr", "h1", "h2", "h3", "h4", "h5", "h6",
-		"dl", "ul", "ol", "menu", "dir", "address", "pre",
-		"listing", "xmp", "head", NULL,
-"head",		"p", NULL,
-"title",	"p", NULL,
-"body",		"head", "style", "link", "title", "p", NULL,
-"frameset",	"head", "style", "link", "title", "p", NULL,
-"li",		"p", "h1", "h2", "h3", "h4", "h5", "h6", "dl", "address",
-		"pre", "listing", "xmp", "head", "li", NULL,
-"hr",		"p", "head", NULL,
-"h1",		"p", "head", NULL,
-"h2",		"p", "head", NULL,
-"h3",		"p", "head", NULL,
-"h4",		"p", "head", NULL,
-"h5",		"p", "head", NULL,
-"h6",		"p", "head", NULL,
-"dir",		"p", "head", NULL,
-"address",	"p", "head", "ul", NULL,
-"pre",		"p", "head", "ul", NULL,
-"listing",	"p", "head", NULL,
-"xmp",		"p", "head", NULL,
-"blockquote",	"p", "head", NULL,
-"dl",		"p", "dt", "menu", "dir", "address", "pre", "listing",
-		"xmp", "head", NULL,
-"dt",		"p", "menu", "dir", "address", "pre", "listing", "xmp",
-                "head", "dd", NULL,
-"dd",		"p", "menu", "dir", "address", "pre", "listing", "xmp",
-                "head", "dt", NULL,
-"ul",		"p", "head", "ol", "menu", "dir", "address", "pre",
-		"listing", "xmp", NULL,
-"ol",		"p", "head", "ul", NULL,
-"menu",		"p", "head", "ul", NULL,
-"p",		"p", "head", "h1", "h2", "h3", "h4", "h5", "h6", FONTSTYLE, NULL,
-"div",		"p", "head", NULL,
-"noscript",	"script", NULL,
-"center",	"font", "b", "i", "p", "head", NULL,
-"a",		"a", "head", NULL,
-"caption",	"p", NULL,
-"colgroup",	"caption", "colgroup", "col", "p", NULL,
-"col",		"caption", "col", "p", NULL,
-"table",	"p", "head", "h1", "h2", "h3", "h4", "h5", "h6", "pre",
-		"listing", "xmp", "a", NULL,
-"th",		"th", "td", "p", "span", "font", "a", "b", "i", "u", NULL,
-"td",		"th", "td", "p", "span", "font", "a", "b", "i", "u", NULL,
-"tr",		"th", "td", "tr", "caption", "col", "colgroup", "p", NULL,
-"thead",	"caption", "col", "colgroup", NULL,
-"tfoot",	"th", "td", "tr", "caption", "col", "colgroup", "thead",
-		"tbody", "p", NULL,
-"tbody",	"th", "td", "tr", "caption", "col", "colgroup", "thead",
-		"tfoot", "tbody", "p", NULL,
-"optgroup",	"option", NULL,
-"option",	"option", NULL,
-"fieldset",	"legend", "p", "head", "h1", "h2", "h3", "h4", "h5", "h6",
-		"pre", "listing", "xmp", "a", NULL,
-/* most tags in in FONTSTYLE, PHRASE and SPECIAL should close <head> */
-"tt",		"head", NULL,
-"i",		"head", NULL,
-"b",		"head", NULL,
-"u",		"head", NULL,
-"s",		"head", NULL,
-"strike",	"head", NULL,
-"big",		"head", NULL,
-"small",	"head", NULL,
-
-"em",		"head", NULL,
-"strong",	"head", NULL,
-"dfn",		"head", NULL,
-"code",		"head", NULL,
-"samp",		"head", NULL,
-"kbd",		"head", NULL,
-"var",		"head", NULL,
-"cite",		"head", NULL,
-"abbr",		"head", NULL,
-"acronym",	"head", NULL,
-
-/* "a" */
-"img",		"head", NULL,
-/* "applet" */
-/* "embed" */
-/* "object" */
-"font",		"head", NULL,
-/* "basefont" */
-"br",		"head", NULL,
-/* "script" */
-"map",		"head", NULL,
-"q",		"head", NULL,
-"sub",		"head", NULL,
-"sup",		"head", NULL,
-"span",		"head", NULL,
-"bdo",		"head", NULL,
-"iframe",	"head", NULL,
-NULL
+static const htmlStartCloseEntry htmlStartClose[] = {
+    { "a", "a" },
+    { "a", "fieldset" },
+    { "a", "table" },
+    { "a", "td" },
+    { "a", "th" },
+    { "address", "dd" },
+    { "address", "dl" },
+    { "address", "dt" },
+    { "address", "form" },
+    { "address", "li" },
+    { "address", "ul" },
+    { "b", "center" },
+    { "b", "p" },
+    { "b", "td" },
+    { "b", "th" },
+    { "big", "p" },
+    { "caption", "col" },
+    { "caption", "colgroup" },
+    { "caption", "tbody" },
+    { "caption", "tfoot" },
+    { "caption", "thead" },
+    { "caption", "tr" },
+    { "col", "col" },
+    { "col", "colgroup" },
+    { "col", "tbody" },
+    { "col", "tfoot" },
+    { "col", "thead" },
+    { "col", "tr" },
+    { "colgroup", "colgroup" },
+    { "colgroup", "tbody" },
+    { "colgroup", "tfoot" },
+    { "colgroup", "thead" },
+    { "colgroup", "tr" },
+    { "dd", "dt" },
+    { "dir", "dd" },
+    { "dir", "dl" },
+    { "dir", "dt" },
+    { "dir", "form" },
+    { "dir", "ul" },
+    { "dl", "form" },
+    { "dl", "li" },
+    { "dt", "dd" },
+    { "dt", "dl" },
+    { "font", "center" },
+    { "font", "td" },
+    { "font", "th" },
+    { "form", "form" },
+    { "h1", "fieldset" },
+    { "h1", "form" },
+    { "h1", "li" },
+    { "h1", "p" },
+    { "h1", "table" },
+    { "h2", "fieldset" },
+    { "h2", "form" },
+    { "h2", "li" },
+    { "h2", "p" },
+    { "h2", "table" },
+    { "h3", "fieldset" },
+    { "h3", "form" },
+    { "h3", "li" },
+    { "h3", "p" },
+    { "h3", "table" },
+    { "h4", "fieldset" },
+    { "h4", "form" },
+    { "h4", "li" },
+    { "h4", "p" },
+    { "h4", "table" },
+    { "h5", "fieldset" },
+    { "h5", "form" },
+    { "h5", "li" },
+    { "h5", "p" },
+    { "h5", "table" },
+    { "h6", "fieldset" },
+    { "h6", "form" },
+    { "h6", "li" },
+    { "h6", "p" },
+    { "h6", "table" },
+    { "head", "a" },
+    { "head", "abbr" },
+    { "head", "acronym" },
+    { "head", "address" },
+    { "head", "b" },
+    { "head", "bdo" },
+    { "head", "big" },
+    { "head", "blockquote" },
+    { "head", "body" },
+    { "head", "br" },
+    { "head", "center" },
+    { "head", "cite" },
+    { "head", "code" },
+    { "head", "dd" },
+    { "head", "dfn" },
+    { "head", "dir" },
+    { "head", "div" },
+    { "head", "dl" },
+    { "head", "dt" },
+    { "head", "em" },
+    { "head", "fieldset" },
+    { "head", "font" },
+    { "head", "form" },
+    { "head", "frameset" },
+    { "head", "h1" },
+    { "head", "h2" },
+    { "head", "h3" },
+    { "head", "h4" },
+    { "head", "h5" },
+    { "head", "h6" },
+    { "head", "hr" },
+    { "head", "i" },
+    { "head", "iframe" },
+    { "head", "img" },
+    { "head", "kbd" },
+    { "head", "li" },
+    { "head", "listing" },
+    { "head", "map" },
+    { "head", "menu" },
+    { "head", "ol" },
+    { "head", "p" },
+    { "head", "pre" },
+    { "head", "q" },
+    { "head", "s" },
+    { "head", "samp" },
+    { "head", "small" },
+    { "head", "span" },
+    { "head", "strike" },
+    { "head", "strong" },
+    { "head", "sub" },
+    { "head", "sup" },
+    { "head", "table" },
+    { "head", "tt" },
+    { "head", "u" },
+    { "head", "ul" },
+    { "head", "var" },
+    { "head", "xmp" },
+    { "hr", "form" },
+    { "i", "center" },
+    { "i", "p" },
+    { "i", "td" },
+    { "i", "th" },
+    { "legend", "fieldset" },
+    { "li", "li" },
+    { "link", "body" },
+    { "link", "frameset" },
+    { "listing", "dd" },
+    { "listing", "dl" },
+    { "listing", "dt" },
+    { "listing", "fieldset" },
+    { "listing", "form" },
+    { "listing", "li" },
+    { "listing", "table" },
+    { "listing", "ul" },
+    { "menu", "dd" },
+    { "menu", "dl" },
+    { "menu", "dt" },
+    { "menu", "form" },
+    { "menu", "ul" },
+    { "ol", "form" },
+    { "ol", "ul" },
+    { "option", "optgroup" },
+    { "option", "option" },
+    { "p", "address" },
+    { "p", "blockquote" },
+    { "p", "body" },
+    { "p", "caption" },
+    { "p", "center" },
+    { "p", "col" },
+    { "p", "colgroup" },
+    { "p", "dd" },
+    { "p", "dir" },
+    { "p", "div" },
+    { "p", "dl" },
+    { "p", "dt" },
+    { "p", "fieldset" },
+    { "p", "form" },
+    { "p", "frameset" },
+    { "p", "h1" },
+    { "p", "h2" },
+    { "p", "h3" },
+    { "p", "h4" },
+    { "p", "h5" },
+    { "p", "h6" },
+    { "p", "head" },
+    { "p", "hr" },
+    { "p", "li" },
+    { "p", "listing" },
+    { "p", "menu" },
+    { "p", "ol" },
+    { "p", "p" },
+    { "p", "pre" },
+    { "p", "table" },
+    { "p", "tbody" },
+    { "p", "td" },
+    { "p", "tfoot" },
+    { "p", "th" },
+    { "p", "title" },
+    { "p", "tr" },
+    { "p", "ul" },
+    { "p", "xmp" },
+    { "pre", "dd" },
+    { "pre", "dl" },
+    { "pre", "dt" },
+    { "pre", "fieldset" },
+    { "pre", "form" },
+    { "pre", "li" },
+    { "pre", "table" },
+    { "pre", "ul" },
+    { "s", "p" },
+    { "script", "noscript" },
+    { "small", "p" },
+    { "span", "td" },
+    { "span", "th" },
+    { "strike", "p" },
+    { "style", "body" },
+    { "style", "frameset" },
+    { "tbody", "tbody" },
+    { "tbody", "tfoot" },
+    { "td", "tbody" },
+    { "td", "td" },
+    { "td", "tfoot" },
+    { "td", "th" },
+    { "td", "tr" },
+    { "tfoot", "tbody" },
+    { "th", "tbody" },
+    { "th", "td" },
+    { "th", "tfoot" },
+    { "th", "th" },
+    { "th", "tr" },
+    { "thead", "tbody" },
+    { "thead", "tfoot" },
+    { "title", "body" },
+    { "title", "frameset" },
+    { "tr", "tbody" },
+    { "tr", "tfoot" },
+    { "tr", "tr" },
+    { "tt", "p" },
+    { "u", "p" },
+    { "u", "td" },
+    { "u", "th" },
+    { "ul", "address" },
+    { "ul", "form" },
+    { "ul", "menu" },
+    { "ul", "ol" },
+    { "ul", "pre" },
+    { "xmp", "dd" },
+    { "xmp", "dl" },
+    { "xmp", "dt" },
+    { "xmp", "fieldset" },
+    { "xmp", "form" },
+    { "xmp", "li" },
+    { "xmp", "table" },
+    { "xmp", "ul" }
 };
 
 /*
@@ -1223,9 +1401,6 @@ static const elementPriority htmlEndPriority[] = {
     {NULL,    100} /* Default priority */
 };
 
-static const char** htmlStartCloseIndex[100];
-static int htmlStartCloseIndexinitialized = 0;
-
 /************************************************************************
  *									*
  *	functions to handle HTML specific data			*
@@ -1235,24 +1410,18 @@ static int htmlStartCloseIndexinitialized = 0;
 /**
  * htmlInitAutoClose:
  *
- * Initialize the htmlStartCloseIndex for fast lookup of closing tags names.
- * This is not reentrant. Call xmlInitParser() once before processing in
- * case of use in multithreaded programs.
+ * This is a no-op now.
  */
 void
 htmlInitAutoClose(void) {
-    int indx, i = 0;
+}
 
-    if (htmlStartCloseIndexinitialized) return;
+static int
+htmlCompareTags(const void *key, const void *member) {
+    const xmlChar *tag = (const xmlChar *) key;
+    const htmlElemDesc *desc = (const htmlElemDesc *) member;
 
-    for (indx = 0;indx < 100;indx ++) htmlStartCloseIndex[indx] = NULL;
-    indx = 0;
-    while ((htmlStartClose[i] != NULL) && (indx < 100 - 1)) {
-        htmlStartCloseIndex[indx++] = (const char**) &htmlStartClose[i];
-	while (htmlStartClose[i] != NULL) i++;
-	i++;
-    }
-    htmlStartCloseIndexinitialized = 1;
+    return(xmlStrcasecmp(tag, BAD_CAST desc->name));
 }
 
 /**
@@ -1265,14 +1434,12 @@ htmlInitAutoClose(void) {
  */
 const htmlElemDesc *
 htmlTagLookup(const xmlChar *tag) {
-    unsigned int i;
+    if (tag == NULL)
+        return(NULL);
 
-    for (i = 0; i < (sizeof(html40ElementTable) /
-                     sizeof(html40ElementTable[0]));i++) {
-        if (!xmlStrcasecmp(tag, BAD_CAST html40ElementTable[i].name))
-	    return((htmlElemDescPtr) &html40ElementTable[i]);
-    }
-    return(NULL);
+    return((const htmlElemDesc *) bsearch(tag, html40ElementTable,
+                sizeof(html40ElementTable) / sizeof(htmlElemDesc),
+                sizeof(htmlElemDesc), htmlCompareTags));
 }
 
 /**
@@ -1293,6 +1460,19 @@ htmlGetEndPriority (const xmlChar *name) {
 }
 
 
+static int
+htmlCompareStartClose(const void *vkey, const void *member) {
+    const htmlStartCloseEntry *key = (const htmlStartCloseEntry *) vkey;
+    const htmlStartCloseEntry *entry = (const htmlStartCloseEntry *) member;
+    int ret;
+
+    ret = strcmp(key->oldTag, entry->oldTag);
+    if (ret == 0)
+        ret = strcmp(key->newTag, entry->newTag);
+
+    return(ret);
+}
+
 /**
  * htmlCheckAutoClose:
  * @newtag:  The new tag name
@@ -1300,37 +1480,21 @@ htmlGetEndPriority (const xmlChar *name) {
  *
  * Checks whether the new tag is one of the registered valid tags for
  * closing old.
- * Initialize the htmlStartCloseIndex for fast lookup of closing tags names.
  *
  * Returns 0 if no, 1 if yes.
  */
 static int
 htmlCheckAutoClose(const xmlChar * newtag, const xmlChar * oldtag)
 {
-    int i, indx;
-    const char **closed = NULL;
-
-    if (htmlStartCloseIndexinitialized == 0)
-        htmlInitAutoClose();
-
-    /* inefficient, but not a big deal */
-    for (indx = 0; indx < 100; indx++) {
-        closed = htmlStartCloseIndex[indx];
-        if (closed == NULL)
-            return (0);
-        if (xmlStrEqual(BAD_CAST * closed, newtag))
-            break;
-    }
-
-    i = closed - htmlStartClose;
-    i++;
-    while (htmlStartClose[i] != NULL) {
-        if (xmlStrEqual(BAD_CAST htmlStartClose[i], oldtag)) {
-            return (1);
-        }
-        i++;
-    }
-    return (0);
+    htmlStartCloseEntry key;
+    void *res;
+
+    key.oldTag = (const char *) oldtag;
+    key.newTag = (const char *) newtag;
+    res = bsearch(&key, htmlStartClose,
+            sizeof(htmlStartClose) / sizeof(htmlStartCloseEntry),
+            sizeof(htmlStartCloseEntry), htmlCompareStartClose);
+    return(res != NULL);
 }
 
 /**
@@ -4043,12 +4207,10 @@ htmlParseEndTag(htmlParserCtxtPtr ctxt)
      * With the exception that the autoclose may have popped stuff out
      * of the stack.
      */
-    if (!xmlStrEqual(name, ctxt->name)) {
-        if ((ctxt->name != NULL) && (!xmlStrEqual(ctxt->name, name))) {
-            htmlParseErr(ctxt, XML_ERR_TAG_NAME_MISMATCH,
-	                 "Opening and ending tag mismatch: %s and %s\n",
-			 name, ctxt->name);
-        }
+    if ((ctxt->name != NULL) && (!xmlStrEqual(ctxt->name, name))) {
+        htmlParseErr(ctxt, XML_ERR_TAG_NAME_MISMATCH,
+                     "Opening and ending tag mismatch: %s and %s\n",
+                     name, ctxt->name);
     }
 
     /*
@@ -5872,7 +6034,8 @@ htmlParseTryOrFinish(htmlParserCtxtPtr ctxt, int terminate) {
 			xmlGenericError(xmlGenericErrorContext,
 				"HPP: Parsing char data\n");
 #endif
-                        while ((cur != '<') && (in->cur < in->end)) {
+                        while ((ctxt->instate != XML_PARSER_EOF) &&
+                               (cur != '<') && (in->cur < in->end)) {
                             if (cur == '&') {
 			        htmlParseReference(ctxt);
                             } else {
diff --git a/chromium/third_party/libxml/src/HTMLtree.c b/chromium/third_party/libxml/src/HTMLtree.c
index 8d0c77957a2..24434d453e1 100644
--- a/chromium/third_party/libxml/src/HTMLtree.c
+++ b/chromium/third_party/libxml/src/HTMLtree.c
@@ -518,7 +518,7 @@ htmlNodeDumpFileFormat(FILE *out, xmlDocPtr doc,
     buf = xmlOutputBufferCreateFile(out, handler);
     if (buf == NULL) return(0);
 
-    htmlNodeDumpFormatOutput(buf, doc, cur, encoding, format);
+    htmlNodeDumpFormatOutput(buf, doc, cur, NULL, format);
 
     ret = xmlOutputBufferClose(buf);
     return(ret);
@@ -670,13 +670,11 @@ htmlDtdDumpOutput(xmlOutputBufferPtr buf, xmlDocPtr doc,
  * @buf:  the HTML buffer output
  * @doc:  the document
  * @cur:  the attribute pointer
- * @encoding:  the encoding string
  *
  * Dump an HTML attribute
  */
 static void
-htmlAttrDumpOutput(xmlOutputBufferPtr buf, xmlDocPtr doc, xmlAttrPtr cur,
-	           const char *encoding ATTRIBUTE_UNUSED) {
+htmlAttrDumpOutput(xmlOutputBufferPtr buf, xmlDocPtr doc, xmlAttrPtr cur) {
     xmlChar *value;
 
     /*
@@ -737,14 +735,15 @@ htmlAttrDumpOutput(xmlOutputBufferPtr buf, xmlDocPtr doc, xmlAttrPtr cur,
  * @buf:  the HTML buffer output
  * @doc:  the document
  * @cur:  the current node
- * @encoding:  the encoding string
+ * @encoding:  the encoding string (unused)
  * @format:  should formatting spaces been added
  *
  * Dump an HTML node, recursive behaviour,children are printed too.
  */
 void
 htmlNodeDumpFormatOutput(xmlOutputBufferPtr buf, xmlDocPtr doc,
-	                 xmlNodePtr cur, const char *encoding, int format) {
+	                 xmlNodePtr cur, const char *encoding ATTRIBUTE_UNUSED,
+                         int format) {
     xmlNodePtr root;
     xmlAttrPtr attr;
     const htmlElemDesc * info;
@@ -788,7 +787,7 @@ htmlNodeDumpFormatOutput(xmlOutputBufferPtr buf, xmlDocPtr doc,
                 xmlNsListDumpOutput(buf, cur->nsDef);
             attr = cur->properties;
             while (attr != NULL) {
-                htmlAttrDumpOutput(buf, doc, attr, encoding);
+                htmlAttrDumpOutput(buf, doc, attr);
                 attr = attr->next;
             }
 
@@ -835,7 +834,7 @@ htmlNodeDumpFormatOutput(xmlOutputBufferPtr buf, xmlDocPtr doc,
             break;
 
         case XML_ATTRIBUTE_NODE:
-            htmlAttrDumpOutput(buf, doc, (xmlAttrPtr) cur, encoding);
+            htmlAttrDumpOutput(buf, doc, (xmlAttrPtr) cur);
             break;
 
         case HTML_TEXT_NODE:
@@ -955,44 +954,45 @@ htmlNodeDumpFormatOutput(xmlOutputBufferPtr buf, xmlDocPtr doc,
  * @buf:  the HTML buffer output
  * @doc:  the document
  * @cur:  the current node
- * @encoding:  the encoding string
+ * @encoding:  the encoding string (unused)
  *
  * Dump an HTML node, recursive behaviour,children are printed too,
  * and formatting returns/spaces are added.
  */
 void
 htmlNodeDumpOutput(xmlOutputBufferPtr buf, xmlDocPtr doc,
-	           xmlNodePtr cur, const char *encoding) {
-    htmlNodeDumpFormatOutput(buf, doc, cur, encoding, 1);
+	           xmlNodePtr cur, const char *encoding ATTRIBUTE_UNUSED) {
+    htmlNodeDumpFormatOutput(buf, doc, cur, NULL, 1);
 }
 
 /**
  * htmlDocContentDumpFormatOutput:
  * @buf:  the HTML buffer output
  * @cur:  the document
- * @encoding:  the encoding string
+ * @encoding:  the encoding string (unused)
  * @format:  should formatting spaces been added
  *
  * Dump an HTML document.
  */
 void
 htmlDocContentDumpFormatOutput(xmlOutputBufferPtr buf, xmlDocPtr cur,
-	                       const char *encoding, int format) {
-    htmlNodeDumpFormatOutput(buf, cur, (xmlNodePtr) cur, encoding, format);
+	                       const char *encoding ATTRIBUTE_UNUSED,
+                               int format) {
+    htmlNodeDumpFormatOutput(buf, cur, (xmlNodePtr) cur, NULL, format);
 }
 
 /**
  * htmlDocContentDumpOutput:
  * @buf:  the HTML buffer output
  * @cur:  the document
- * @encoding:  the encoding string
+ * @encoding:  the encoding string (unused)
  *
  * Dump an HTML document. Formatting return/spaces are added.
  */
 void
 htmlDocContentDumpOutput(xmlOutputBufferPtr buf, xmlDocPtr cur,
-	                 const char *encoding) {
-    htmlNodeDumpFormatOutput(buf, cur, (xmlNodePtr) cur, encoding, 1);
+	                 const char *encoding ATTRIBUTE_UNUSED) {
+    htmlNodeDumpFormatOutput(buf, cur, (xmlNodePtr) cur, NULL, 1);
 }
 
 /************************************************************************
diff --git a/chromium/third_party/libxml/src/SAX2.c b/chromium/third_party/libxml/src/SAX2.c
index 4450a3f6e5c..99019a984cd 100644
--- a/chromium/third_party/libxml/src/SAX2.c
+++ b/chromium/third_party/libxml/src/SAX2.c
@@ -2493,20 +2493,21 @@ xmlSAX2Reference(void *ctx, const xmlChar *name)
 }
 
 /**
- * xmlSAX2Characters:
+ * xmlSAX2Text:
  * @ctx: the user data (XML parser context)
  * @ch:  a xmlChar string
  * @len: the number of xmlChar
+ * @type: text or cdata
  *
- * receiving some chars from the parser.
+ * Append characters.
  */
-void
-xmlSAX2Characters(void *ctx, const xmlChar *ch, int len)
+static void
+xmlSAX2Text(xmlParserCtxtPtr ctxt, const xmlChar *ch, int len,
+            xmlElementType type)
 {
-    xmlParserCtxtPtr ctxt = (xmlParserCtxtPtr) ctx;
     xmlNodePtr lastChild;
 
-    if (ctx == NULL) return;
+    if (ctxt == NULL) return;
 #ifdef DEBUG_SAX
     xmlGenericError(xmlGenericErrorContext,
 	    "SAX.xmlSAX2Characters(%.30s, %d)\n", ch, len);
@@ -2535,7 +2536,10 @@ xmlSAX2Characters(void *ctx, const xmlChar *ch, int len)
      * elements. Use an attribute in the structure !!!
      */
     if (lastChild == NULL) {
-        lastChild = xmlSAX2TextNode(ctxt, ch, len);
+        if (type == XML_TEXT_NODE)
+            lastChild = xmlSAX2TextNode(ctxt, ch, len);
+        else
+            lastChild = xmlNewCDataBlock(ctxt->myDoc, ch, len);
 	if (lastChild != NULL) {
 	    ctxt->node->children = lastChild;
 	    ctxt->node->last = lastChild;
@@ -2549,8 +2553,9 @@ xmlSAX2Characters(void *ctx, const xmlChar *ch, int len)
 	}
     } else {
 	int coalesceText = (lastChild != NULL) &&
-	    (lastChild->type == XML_TEXT_NODE) &&
-	    (lastChild->name == xmlStringText);
+	    (lastChild->type == type) &&
+	    ((type != XML_TEXT_NODE) ||
+             (lastChild->name == xmlStringText));
 	if ((coalesceText) && (ctxt->nodemem != 0)) {
 	    /*
 	     * The whole point of maintaining nodelen and nodemem,
@@ -2607,7 +2612,10 @@ xmlSAX2Characters(void *ctx, const xmlChar *ch, int len)
 	    }
 	} else {
 	    /* Mixed content, first time */
-	    lastChild = xmlSAX2TextNode(ctxt, ch, len);
+            if (type == XML_TEXT_NODE)
+                lastChild = xmlSAX2TextNode(ctxt, ch, len);
+            else
+                lastChild = xmlNewCDataBlock(ctxt->myDoc, ch, len);
 	    if (lastChild != NULL) {
 		xmlAddChild(ctxt->node, lastChild);
 		if (ctxt->node->children != NULL) {
@@ -2620,6 +2628,20 @@ xmlSAX2Characters(void *ctx, const xmlChar *ch, int len)
 }
 
 /**
+ * xmlSAX2Characters:
+ * @ctx: the user data (XML parser context)
+ * @ch:  a xmlChar string
+ * @len: the number of xmlChar
+ *
+ * receiving some chars from the parser.
+ */
+void
+xmlSAX2Characters(void *ctx, const xmlChar *ch, int len)
+{
+    xmlSAX2Text((xmlParserCtxtPtr) ctx, ch, len, XML_TEXT_NODE);
+}
+
+/**
  * xmlSAX2IgnorableWhitespace:
  * @ctx: the user data (XML parser context)
  * @ch:  a xmlChar string
@@ -2775,27 +2797,7 @@ xmlSAX2Comment(void *ctx, const xmlChar *value)
 void
 xmlSAX2CDataBlock(void *ctx, const xmlChar *value, int len)
 {
-    xmlParserCtxtPtr ctxt = (xmlParserCtxtPtr) ctx;
-    xmlNodePtr ret, lastChild;
-
-    if (ctx == NULL) return;
-#ifdef DEBUG_SAX
-    xmlGenericError(xmlGenericErrorContext,
-	    "SAX.pcdata(%.10s, %d)\n", value, len);
-#endif
-    lastChild = xmlGetLastChild(ctxt->node);
-#ifdef DEBUG_SAX_TREE
-    xmlGenericError(xmlGenericErrorContext,
-	    "add chars to %s \n", ctxt->node->name);
-#endif
-    if ((lastChild != NULL) &&
-        (lastChild->type == XML_CDATA_SECTION_NODE)) {
-	xmlTextConcat(lastChild, value, len);
-    } else {
-	ret = xmlNewCDataBlock(ctxt->myDoc, value, len);
-	if (xmlAddChild(ctxt->node, ret) == NULL)
-		xmlFreeNode(ret);
-    }
+    xmlSAX2Text((xmlParserCtxtPtr) ctx, value, len, XML_CDATA_SECTION_NODE);
 }
 
 static int xmlSAX2DefaultVersionValue = 2;
diff --git a/chromium/third_party/libxml/src/aclocal.m4 b/chromium/third_party/libxml/src/aclocal.m4
index 1fc80003ea3..a671949bfa6 100644
--- a/chromium/third_party/libxml/src/aclocal.m4
+++ b/chromium/third_party/libxml/src/aclocal.m4
@@ -1,4 +1,4 @@
-# generated automatically by aclocal 1.16.2 -*- Autoconf -*-
+# generated automatically by aclocal 1.16.3 -*- Autoconf -*-
 
 # Copyright (C) 1996-2020 Free Software Foundation, Inc.
 
@@ -14,8 +14,8 @@
 m4_ifndef([AC_CONFIG_MACRO_DIRS], [m4_defun([_AM_CONFIG_MACRO_DIRS], [])m4_defun([AC_CONFIG_MACRO_DIRS], [_AM_CONFIG_MACRO_DIRS($@)])])
 m4_ifndef([AC_AUTOCONF_VERSION],
   [m4_copy([m4_PACKAGE_VERSION], [AC_AUTOCONF_VERSION])])dnl
-m4_if(m4_defn([AC_AUTOCONF_VERSION]), [2.69],,
-[m4_warning([this file was generated for autoconf 2.69.
+m4_if(m4_defn([AC_AUTOCONF_VERSION]), [2.71],,
+[m4_warning([this file was generated for autoconf 2.71.
 You have another version of autoconf.  It may work, but is not guaranteed to.
 If you have problems, you may need to regenerate the build system entirely.
 To do so, use the procedure documented by the package, typically 'autoreconf'.])])
@@ -311,7 +311,7 @@ AC_DEFUN([AM_AUTOMAKE_VERSION],
 [am__api_version='1.16'
 dnl Some users find AM_AUTOMAKE_VERSION and mistake it for a way to
 dnl require some minimum version.  Point them to the right macro.
-m4_if([$1], [1.16.2], [],
+m4_if([$1], [1.16.3], [],
       [AC_FATAL([Do not call $0, use AM_INIT_AUTOMAKE([$1]).])])dnl
 ])
 
@@ -327,7 +327,7 @@ m4_define([_AM_AUTOCONF_VERSION], [])
 # Call AM_AUTOMAKE_VERSION and AM_AUTOMAKE_VERSION so they can be traced.
 # This function is AC_REQUIREd by AM_INIT_AUTOMAKE.
 AC_DEFUN([AM_SET_CURRENT_AUTOMAKE_VERSION],
-[AM_AUTOMAKE_VERSION([1.16.2])dnl
+[AM_AUTOMAKE_VERSION([1.16.3])dnl
 m4_ifndef([AC_AUTOCONF_VERSION],
   [m4_copy([m4_PACKAGE_VERSION], [AC_AUTOCONF_VERSION])])dnl
 _AM_AUTOCONF_VERSION(m4_defn([AC_AUTOCONF_VERSION]))])
@@ -1015,12 +1015,7 @@ AC_DEFUN([AM_MISSING_HAS_RUN],
 [AC_REQUIRE([AM_AUX_DIR_EXPAND])dnl
 AC_REQUIRE_AUX_FILE([missing])dnl
 if test x"${MISSING+set}" != xset; then
-  case $am_aux_dir in
-  *\ * | *\	*)
-    MISSING="\${SHELL} \"$am_aux_dir/missing\"" ;;
-  *)
-    MISSING="\${SHELL} $am_aux_dir/missing" ;;
-  esac
+  MISSING="\${SHELL} '$am_aux_dir/missing'"
 fi
 # Use eval to expand $SHELL
 if eval "$MISSING --is-lightweight"; then
diff --git a/chromium/third_party/libxml/src/config.h.in b/chromium/third_party/libxml/src/config.h.in
index 5f87036599c..a55d4e18572 100644
--- a/chromium/third_party/libxml/src/config.h.in
+++ b/chromium/third_party/libxml/src/config.h.in
@@ -90,9 +90,6 @@
 /* Define to 1 if you have the <math.h> header file. */
 #undef HAVE_MATH_H
 
-/* Define to 1 if you have the <memory.h> header file. */
-#undef HAVE_MEMORY_H
-
 /* Define to 1 if you have the `mmap' function. */
 #undef HAVE_MMAP
 
@@ -164,6 +161,9 @@
 /* Define to 1 if you have the <stdint.h> header file. */
 #undef HAVE_STDINT_H
 
+/* Define to 1 if you have the <stdio.h> header file. */
+#undef HAVE_STDIO_H
+
 /* Define to 1 if you have the <stdlib.h> header file. */
 #undef HAVE_STDLIB_H
 
@@ -262,7 +262,9 @@
 /* Type cast for the send() function 2nd arg */
 #undef SEND_ARG2_CAST
 
-/* Define to 1 if you have the ANSI C header files. */
+/* Define to 1 if all of the C90 standard headers exist (not just the ones
+   required in a freestanding environment). This macro is provided for
+   backward compatibility; new code need not use it. */
 #undef STDC_HEADERS
 
 /* Support for IPv6 */
diff --git a/chromium/third_party/libxml/src/encoding.c b/chromium/third_party/libxml/src/encoding.c
index 841540ed9ee..1bff871bc01 100644
--- a/chromium/third_party/libxml/src/encoding.c
+++ b/chromium/third_party/libxml/src/encoding.c
@@ -373,6 +373,11 @@ UTF8ToUTF8(unsigned char* out, int *outlen,
     if (len < 0)
 	return(-1);
 
+    /*
+     * FIXME: Conversion functions must assure valid UTF-8, so we have
+     * to check for UTF-8 validity. Preferably, this converter shouldn't
+     * be used at all.
+     */
     memcpy(out, inb, len);
 
     *outlen = len;
diff --git a/chromium/third_party/libxml/src/entities.c b/chromium/third_party/libxml/src/entities.c
index 4b41fe970da..8307471246d 100644
--- a/chromium/third_party/libxml/src/entities.c
+++ b/chromium/third_party/libxml/src/entities.c
@@ -211,7 +211,7 @@ xmlAddEntity(xmlDtdPtr dtd, const xmlChar *name, int type,
 	  const xmlChar *content) {
     xmlDictPtr dict = NULL;
     xmlEntitiesTablePtr table = NULL;
-    xmlEntityPtr ret;
+    xmlEntityPtr ret, predef;
 
     if (name == NULL)
 	return(NULL);
@@ -224,6 +224,44 @@ xmlAddEntity(xmlDtdPtr dtd, const xmlChar *name, int type,
         case XML_INTERNAL_GENERAL_ENTITY:
         case XML_EXTERNAL_GENERAL_PARSED_ENTITY:
         case XML_EXTERNAL_GENERAL_UNPARSED_ENTITY:
+            predef = xmlGetPredefinedEntity(name);
+            if (predef != NULL) {
+                int valid = 0;
+
+                /* 4.6 Predefined Entities */
+                if ((type == XML_INTERNAL_GENERAL_ENTITY) &&
+                    (content != NULL)) {
+                    int c = predef->content[0];
+
+                    if (((content[0] == c) && (content[1] == 0)) &&
+                        ((c == '>') || (c == '\'') || (c == '"'))) {
+                        valid = 1;
+                    } else if ((content[0] == '&') && (content[1] == '#')) {
+                        if (content[2] == 'x') {
+                            xmlChar *hex = BAD_CAST "0123456789ABCDEF";
+                            xmlChar ref[] = "00;";
+
+                            ref[0] = hex[c / 16 % 16];
+                            ref[1] = hex[c % 16];
+                            if (xmlStrcasecmp(&content[3], ref) == 0)
+                                valid = 1;
+                        } else {
+                            xmlChar ref[] = "00;";
+
+                            ref[0] = '0' + c / 10 % 10;
+                            ref[1] = '0' + c % 10;
+                            if (xmlStrEqual(&content[2], ref))
+                                valid = 1;
+                        }
+                    }
+                }
+                if (!valid) {
+                    xmlEntitiesErr(XML_ERR_ENTITY_PROCESSING,
+                            "xmlAddEntity: invalid redeclaration of predefined"
+                            " entity");
+                    return(NULL);
+                }
+            }
 	    if (dtd->entities == NULL)
 		dtd->entities = xmlHashCreateDict(0, dict);
 	    table = dtd->entities;
diff --git a/chromium/third_party/libxml/src/include/libxml/c14n.h b/chromium/third_party/libxml/src/include/libxml/c14n.h
index d74847df842..af93de63a4c 100644
--- a/chromium/third_party/libxml/src/include/libxml/c14n.h
+++ b/chromium/third_party/libxml/src/include/libxml/c14n.h
@@ -16,17 +16,19 @@
  */
 #ifndef __XML_C14N_H__
 #define __XML_C14N_H__
+
+#include <libxml/xmlversion.h>
+
 #ifdef LIBXML_C14N_ENABLED
 #ifdef LIBXML_OUTPUT_ENABLED
 
+#include <libxml/tree.h>
+#include <libxml/xpath.h>
+
 #ifdef __cplusplus
 extern "C" {
 #endif /* __cplusplus */
 
-#include <libxml/xmlversion.h>
-#include <libxml/tree.h>
-#include <libxml/xpath.h>
-
 /*
  * XML Canonicalization
  * http://www.w3.org/TR/xml-c14n
diff --git a/chromium/third_party/libxml/src/libxml.m4 b/chromium/third_party/libxml/src/libxml.m4
index b5df9158d0b..09de9fe2def 100644
--- a/chromium/third_party/libxml/src/libxml.m4
+++ b/chromium/third_party/libxml/src/libxml.m4
@@ -1,4 +1,6 @@
 # Configure paths for LIBXML2
+# Simon Josefsson 2020-02-12
+# Fix autoconf 2.70+ warnings
 # Mike Hommey 2004-06-19
 # use CPPFLAGS instead of CFLAGS
 # Toshio Kuratomi 2001-04-21
@@ -58,7 +60,8 @@ dnl Now check if the installed libxml is sufficiently new.
 dnl (Also sanity checks the results of xml2-config to some extent)
 dnl
       rm -f conf.xmltest
-      AC_TRY_RUN([
+      AC_RUN_IFELSE(
+            [AC_LANG_SOURCE([[
 #include <stdlib.h>
 #include <stdio.h>
 #include <string.h>
@@ -133,7 +136,7 @@ main()
     }
   return 1;
 }
-],, no_xml=yes,[echo $ac_n "cross compiling; assumed OK... $ac_c"])
+]])],, no_xml=yes,[echo $ac_n "cross compiling; assumed OK... $ac_c"])
        CPPFLAGS="$ac_save_CPPFLAGS"
        LIBS="$ac_save_LIBS"
      fi
@@ -156,10 +159,11 @@ main()
           echo "*** Could not run libxml test program, checking why..."
           CPPFLAGS="$CPPFLAGS $XML_CPPFLAGS"
           LIBS="$LIBS $XML_LIBS"
-          AC_TRY_LINK([
+	  AC_LINK_IFELSE(
+            [AC_LANG_PROGRAM([[
 #include <libxml/xmlversion.h>
 #include <stdio.h>
-],      [ LIBXML_TEST_VERSION; return 0;],
+]],    [[ LIBXML_TEST_VERSION; return 0;]])],
         [ echo "*** The test program compiled, but did not run. This usually means"
           echo "*** that the run-time linker is not finding LIBXML or finding the wrong"
           echo "*** version of LIBXML. If it is not finding LIBXML, you'll need to set your"
diff --git a/chromium/third_party/libxml/src/libxml2.spec b/chromium/third_party/libxml/src/libxml2.spec
index 626f900ffb9..017e34ee748 100644
--- a/chromium/third_party/libxml/src/libxml2.spec
+++ b/chromium/third_party/libxml/src/libxml2.spec
@@ -204,6 +204,6 @@ rm -fr %{buildroot}
 %endif # with_python3
 
 %changelog
-* Mon Feb  1 2021 Daniel Veillard <veillard@redhat.com>
+* Thu May  6 2021 Daniel Veillard <veillard@redhat.com>
 - upstream release 2.9.10 see http://xmlsoft.org/news.html
 
diff --git a/chromium/third_party/libxml/src/parser.c b/chromium/third_party/libxml/src/parser.c
index 705c7216882..a8ba76d75e8 100644
--- a/chromium/third_party/libxml/src/parser.c
+++ b/chromium/third_party/libxml/src/parser.c
@@ -2703,8 +2703,10 @@ xmlStringLenDecodeEntities(xmlParserCtxtPtr ctxt, const xmlChar *str, int len,
 		rep = xmlStringDecodeEntities(ctxt, ent->content, what,
 			                      0, 0, 0);
 		ctxt->depth--;
-		if (rep == NULL)
+		if (rep == NULL) {
+                    ent->content[0] = 0;
                     goto int_error;
+                }
 
                 current = rep;
                 while (*current != 0) { /* non input consuming loop */
@@ -2759,8 +2761,11 @@ xmlStringLenDecodeEntities(xmlParserCtxtPtr ctxt, const xmlChar *str, int len,
 		rep = xmlStringDecodeEntities(ctxt, ent->content, what,
 			                      0, 0, 0);
 		ctxt->depth--;
-		if (rep == NULL)
+		if (rep == NULL) {
+                    if (ent->content != NULL)
+                        ent->content[0] = 0;
                     goto int_error;
+                }
                 current = rep;
                 while (*current != 0) { /* non input consuming loop */
                     buffer[nbchars++] = *current++;
@@ -4223,6 +4228,7 @@ xmlParseSystemLiteral(xmlParserCtxtPtr ctxt) {
 	}
 	count++;
 	if (count > 50) {
+	    SHRINK;
 	    GROW;
 	    count = 0;
             if (ctxt->instate == XML_PARSER_EOF) {
@@ -4310,6 +4316,7 @@ xmlParsePubidLiteral(xmlParserCtxtPtr ctxt) {
 	buf[len++] = cur;
 	count++;
 	if (count > 50) {
+	    SHRINK;
 	    GROW;
 	    count = 0;
             if (ctxt->instate == XML_PARSER_EOF) {
@@ -4590,6 +4597,7 @@ xmlParseCharDataComplex(xmlParserCtxtPtr ctxt, int cdata) {
 	}
 	count++;
 	if (count > 50) {
+	    SHRINK;
 	    GROW;
 	    count = 0;
             if (ctxt->instate == XML_PARSER_EOF)
@@ -4795,6 +4803,7 @@ xmlParseCommentComplex(xmlParserCtxtPtr ctxt, xmlChar *buf,
 
 	count++;
 	if (count > 50) {
+	    SHRINK;
 	    GROW;
 	    count = 0;
             if (ctxt->instate == XML_PARSER_EOF) {
@@ -5205,6 +5214,7 @@ xmlParsePI(xmlParserCtxtPtr ctxt) {
 		}
 		count++;
 		if (count > 50) {
+		    SHRINK;
 		    GROW;
                     if (ctxt->instate == XML_PARSER_EOF) {
                         xmlFree(buf);
@@ -6217,6 +6227,8 @@ xmlParseElementChildrenContentDeclPriv(xmlParserCtxtPtr ctxt, int inputchk,
 	SKIP_BLANKS;
         cur = ret = xmlParseElementChildrenContentDeclPriv(ctxt, inputid,
                                                            depth + 1);
+        if (cur == NULL)
+            return(NULL);
 	SKIP_BLANKS;
 	GROW;
     } else {
@@ -6350,6 +6362,11 @@ xmlParseElementChildrenContentDeclPriv(xmlParserCtxtPtr ctxt, int inputchk,
 	    SKIP_BLANKS;
 	    last = xmlParseElementChildrenContentDeclPriv(ctxt, inputid,
                                                           depth + 1);
+            if (last == NULL) {
+		if (ret != NULL)
+		    xmlFreeDocElementContent(ctxt->myDoc, ret);
+		return(NULL);
+            }
 	    SKIP_BLANKS;
 	} else {
 	    elem = xmlParseName(ctxt);
@@ -9816,6 +9833,7 @@ xmlParseCDSect(xmlParserCtxtPtr ctxt) {
 	sl = l;
 	count++;
 	if (count > 50) {
+	    SHRINK;
 	    GROW;
             if (ctxt->instate == XML_PARSER_EOF) {
 		xmlFree(buf);
diff --git a/chromium/third_party/libxml/src/parserInternals.c b/chromium/third_party/libxml/src/parserInternals.c
index e3828afed4d..a731c169340 100644
--- a/chromium/third_party/libxml/src/parserInternals.c
+++ b/chromium/third_party/libxml/src/parserInternals.c
@@ -1153,6 +1153,11 @@ xmlSwitchInputEncodingInt(xmlParserCtxtPtr ctxt, xmlParserInputPtr input,
              * Note: this is a bit dangerous, but that's what it
              * takes to use nearly compatible signature for different
              * encodings.
+             *
+             * FIXME: Encoders might buffer partial byte sequences, so
+             * this probably can't work. We should return an error and
+             * make sure that callers never try to switch the encoding
+             * twice.
              */
             xmlCharEncCloseFunc(input->buf->encoder);
             input->buf->encoder = handler;
diff --git a/chromium/third_party/libxml/src/tree.c b/chromium/third_party/libxml/src/tree.c
index 2130d55d5d6..c707f598e8d 100644
--- a/chromium/third_party/libxml/src/tree.c
+++ b/chromium/third_party/libxml/src/tree.c
@@ -1310,6 +1310,16 @@ xmlStringLenGetNodeList(const xmlDoc *doc, const xmlChar *value, int len) {
 		else
 		    tmp = 0;
 		while (tmp != ';') { /* Non input consuming loop */
+                    /*
+                     * If you find an integer overflow here when fuzzing,
+                     * the bug is probably elsewhere. This function should
+                     * only receive entities that were already validated by
+                     * the parser, typically by xmlParseAttValueComplex
+                     * calling xmlStringDecodeEntities.
+                     *
+                     * So it's better *not* to check for overflow to
+                     * potentially discover new bugs.
+                     */
 		    if ((tmp >= '0') && (tmp <= '9'))
 			charval = charval * 16 + (tmp - '0');
 		    else if ((tmp >= 'a') && (tmp <= 'f'))
@@ -1338,6 +1348,7 @@ xmlStringLenGetNodeList(const xmlDoc *doc, const xmlChar *value, int len) {
 		else
 		    tmp = 0;
 		while (tmp != ';') { /* Non input consuming loops */
+                    /* Don't check for integer overflow, see above. */
 		    if ((tmp >= '0') && (tmp <= '9'))
 			charval = charval * 10 + (tmp - '0');
 		    else {
@@ -1517,6 +1528,7 @@ xmlStringGetNodeList(const xmlDoc *doc, const xmlChar *value) {
 		cur += 3;
 		tmp = *cur;
 		while (tmp != ';') { /* Non input consuming loop */
+                    /* Don't check for integer overflow, see above. */
 		    if ((tmp >= '0') && (tmp <= '9'))
 			charval = charval * 16 + (tmp - '0');
 		    else if ((tmp >= 'a') && (tmp <= 'f'))
@@ -1539,6 +1551,7 @@ xmlStringGetNodeList(const xmlDoc *doc, const xmlChar *value) {
 		cur += 2;
 		tmp = *cur;
 		while (tmp != ';') { /* Non input consuming loops */
+                    /* Don't check for integer overflow, see above. */
 		    if ((tmp >= '0') && (tmp <= '9'))
 			charval = charval * 10 + (tmp - '0');
 		    else {
@@ -1888,12 +1901,6 @@ xmlNewPropInternal(xmlNodePtr node, xmlNsPtr ns,
     if (value != NULL) {
         xmlNodePtr tmp;
 
-        if(!xmlCheckUTF8(value)) {
-            xmlTreeErr(XML_TREE_NOT_UTF8, (xmlNodePtr) doc,
-                       NULL);
-            if (doc != NULL)
-                doc->encoding = xmlStrdup(BAD_CAST "ISO-8859-1");
-        }
         cur->children = xmlNewDocText(doc, value);
         cur->last = NULL;
         tmp = cur->children;
@@ -2013,6 +2020,11 @@ xmlNewNsPropEatName(xmlNodePtr node, xmlNsPtr ns, xmlChar *name,
  * @value:  the value of the attribute
  *
  * Create a new property carried by a document.
+ * NOTE: @value is supposed to be a piece of XML CDATA, so it allows entity
+ *       references, but XML special chars need to be escaped first by using
+ *       xmlEncodeEntitiesReentrant(). Use xmlNewProp() if you don't need
+ *       entities support.
+ *
  * Returns a pointer to the attribute
  */
 xmlAttrPtr
@@ -4558,6 +4570,7 @@ xmlCopyDoc(xmlDocPtr doc, int recursive) {
     if (doc == NULL) return(NULL);
     ret = xmlNewDoc(doc->version);
     if (ret == NULL) return(NULL);
+    ret->type = doc->type;
     if (doc->name != NULL)
         ret->name = xmlMemStrdup(doc->name);
     if (doc->encoding != NULL)
@@ -4880,7 +4893,9 @@ xmlGetNodePath(const xmlNode *node)
             }
             next = ((xmlAttrPtr) cur)->parent;
         } else {
-            next = cur->parent;
+            xmlFree(buf);
+            xmlFree(buffer);
+            return (NULL);
         }
 
         /*
@@ -6575,6 +6590,16 @@ xmlGetPropNodeInternal(const xmlNode *node, const xmlChar *name,
 		attrDecl = xmlGetDtdQAttrDesc(doc->extSubset,
 		    elemQName, name, NULL);
 	    }
+        } else if (xmlStrEqual(nsName, XML_XML_NAMESPACE)) {
+	    /*
+	    * The XML namespace must be bound to prefix 'xml'.
+	    */
+	    attrDecl = xmlGetDtdQAttrDesc(doc->intSubset,
+		elemQName, name, BAD_CAST "xml");
+	    if ((attrDecl == NULL) && (doc->extSubset != NULL)) {
+		attrDecl = xmlGetDtdQAttrDesc(doc->extSubset,
+		    elemQName, name, BAD_CAST "xml");
+	    }
 	} else {
 	    xmlNsPtr *nsList, *cur;
 
@@ -6921,12 +6946,6 @@ xmlSetNsProp(xmlNodePtr node, xmlNsPtr ns, const xmlChar *name,
 	if (value != NULL) {
 	    xmlNodePtr tmp;
 
-	    if(!xmlCheckUTF8(value)) {
-	        xmlTreeErr(XML_TREE_NOT_UTF8, (xmlNodePtr) node->doc,
-	                   NULL);
-                if (node->doc != NULL)
-                    node->doc->encoding = xmlStrdup(BAD_CAST "ISO-8859-1");
-	    }
 	    prop->children = xmlNewDocText(node->doc, value);
 	    prop->last = NULL;
 	    tmp = prop->children;
diff --git a/chromium/third_party/libxml/src/xpath.c b/chromium/third_party/libxml/src/xpath.c
index 90f10ca9bcf..711bd2a33c9 100644
--- a/chromium/third_party/libxml/src/xpath.c
+++ b/chromium/third_party/libxml/src/xpath.c
@@ -488,14 +488,6 @@ int wrap_cmp( xmlNodePtr x, xmlNodePtr y );
  *									*
  ************************************************************************/
 
-#ifndef INFINITY
-#define INFINITY (DBL_MAX * DBL_MAX)
-#endif
-
-#ifndef NAN
-#define NAN (INFINITY / INFINITY)
-#endif
-
 double xmlXPathNAN;
 double xmlXPathPINF;
 double xmlXPathNINF;
@@ -505,11 +497,14 @@ double xmlXPathNINF;
  *
  * Initialize the XPath environment
  */
+ATTRIBUTE_NO_SANITIZE("float-divide-by-zero")
 void
 xmlXPathInit(void) {
-    xmlXPathNAN = NAN;
-    xmlXPathPINF = INFINITY;
-    xmlXPathNINF = -INFINITY;
+    /* MSVC doesn't allow division by zero in constant expressions. */
+    double zero = 0.0;
+    xmlXPathNAN = 0.0 / zero;
+    xmlXPathPINF = 1.0 / zero;
+    xmlXPathNINF = -xmlXPathPINF;
 }
 
 /**
@@ -538,9 +533,9 @@ xmlXPathIsInf(double val) {
 #ifdef isinf
     return isinf(val) ? (val > 0 ? 1 : -1) : 0;
 #else
-    if (val >= INFINITY)
+    if (val >= xmlXPathPINF)
         return 1;
-    if (val <= -INFINITY)
+    if (val <= -xmlXPathPINF)
         return -1;
     return 0;
 #endif
@@ -5873,10 +5868,10 @@ xmlXPathCastNodeToNumber (xmlNodePtr node) {
     double ret;
 
     if (node == NULL)
-	return(NAN);
+	return(xmlXPathNAN);
     strval = xmlXPathCastNodeToString(node);
     if (strval == NULL)
-	return(NAN);
+	return(xmlXPathNAN);
     ret = xmlXPathCastStringToNumber(strval);
     xmlFree(strval);
 
@@ -5897,7 +5892,7 @@ xmlXPathCastNodeSetToNumber (xmlNodeSetPtr ns) {
     double ret;
 
     if (ns == NULL)
-	return(NAN);
+	return(xmlXPathNAN);
     str = xmlXPathCastNodeSetToString(ns);
     ret = xmlXPathCastStringToNumber(str);
     xmlFree(str);
@@ -5917,13 +5912,13 @@ xmlXPathCastToNumber(xmlXPathObjectPtr val) {
     double ret = 0.0;
 
     if (val == NULL)
-	return(NAN);
+	return(xmlXPathNAN);
     switch (val->type) {
     case XPATH_UNDEFINED:
 #ifdef DEBUG_EXPR
 	xmlGenericError(xmlGenericErrorContext, "NUMBER: undefined\n");
 #endif
-	ret = NAN;
+	ret = xmlXPathNAN;
 	break;
     case XPATH_NODESET:
     case XPATH_XSLT_TREE:
@@ -5943,7 +5938,7 @@ xmlXPathCastToNumber(xmlXPathObjectPtr val) {
     case XPATH_RANGE:
     case XPATH_LOCATIONSET:
 	TODO;
-	ret = NAN;
+	ret = xmlXPathNAN;
 	break;
     }
     return(ret);
@@ -7570,7 +7565,7 @@ xmlXPathModValues(xmlXPathParserContextPtr ctxt) {
     CHECK_TYPE(XPATH_NUMBER);
     arg1 = ctxt->value->floatval;
     if (arg2 == 0)
-	ctxt->value->floatval = NAN;
+	ctxt->value->floatval = xmlXPathNAN;
     else {
 	ctxt->value->floatval = fmod(arg1, arg2);
     }
@@ -10000,7 +9995,7 @@ xmlXPathStringEvalNumber(const xmlChar *str) {
     if (cur == NULL) return(0);
     while (IS_BLANK_CH(*cur)) cur++;
     if ((*cur != '.') && ((*cur < '0') || (*cur > '9')) && (*cur != '-')) {
-        return(NAN);
+        return(xmlXPathNAN);
     }
     if (*cur == '-') {
 	isneg = 1;
@@ -10036,7 +10031,7 @@ xmlXPathStringEvalNumber(const xmlChar *str) {
 
         cur++;
 	if (((*cur < '0') || (*cur > '9')) && (!ok)) {
-	    return(NAN);
+	    return(xmlXPathNAN);
 	}
         while (*cur == '0') {
 	    frac = frac + 1;
@@ -10069,7 +10064,7 @@ xmlXPathStringEvalNumber(const xmlChar *str) {
       }
     }
     while (IS_BLANK_CH(*cur)) cur++;
-    if (*cur != 0) return(NAN);
+    if (*cur != 0) return(xmlXPathNAN);
     if (isneg) ret = -ret;
     if (is_exponent_negative) exponent = -exponent;
     ret *= pow(10.0, (double)exponent);