[PATCH 5/6] virxml: Introduce parsing APIs that keep indentation

[Michal Privoznik <mprivozn@xxxxxxxxxx>]

When parsing an XML it may be important to keep indentation to
produce a better looking result when formatting the XML back.
Just look at all those xmlKeepBlanksDefault() calls just before
virXMLParse() is called.

Anyway, as of libxml2 commit v2.12.0~108 xmlKeepBlanksDefault()
is deprecated. Therefore, introduce virXMLParse...WithIndent()
variants which would do exactly xmlKeepBlanksDefault() did but
with non-deprecated APIs.

Signed-off-by: Michal Privoznik <mprivozn@xxxxxxxxxx>
---
 src/util/virxml.c | 15 +++++++++++++--
 src/util/virxml.h | 29 +++++++++++++++++++++++++----
 2 files changed, 38 insertions(+), 6 deletions(-)

diff --git a/src/util/virxml.c b/src/util/virxml.c
index 31685cddde..e94708448a 100644
--- a/src/util/virxml.c
+++ b/src/util/virxml.c
@@ -1129,14 +1129,16 @@ virXMLParseHelper(int domcode,
                   const char *rootelement,
                   xmlXPathContextPtr *ctxt,
                   const char *schemafile,
-                  bool validate)
+                  bool validate,
+                  bool keepindent)
 {
     struct virParserData private;
     g_autoptr(xmlParserCtxt) pctxt = NULL;
     g_autoptr(xmlDoc) xml = NULL;
     xmlNodePtr rootnode;
     const char *docname;
-    const int parseFlags = XML_PARSE_NONET |
+    int oldIndentTreeOutput = 0;
+    int parseFlags = XML_PARSE_NONET |
         XML_PARSE_NOWARNING;
 
     if (filename)
@@ -1155,12 +1157,21 @@ virXMLParseHelper(int domcode,
     pctxt->_private = &private;
     pctxt->sax->error = catchXMLError;
 
+    if (keepindent) {
+        parseFlags |= XML_PARSE_NOBLANKS;
+        xmlIndentTreeOutput = 1;
+    }
+
     if (filename) {
         xml = xmlCtxtReadFile(pctxt, filename, NULL, parseFlags);
     } else {
         xml = xmlCtxtReadDoc(pctxt, BAD_CAST xmlStr, url, NULL, parseFlags);
     }
 
+    if (keepindent) {
+        xmlIndentTreeOutput = oldIndentTreeOutput;
+    }
+
     if (!xml) {
         if (virGetLastErrorCode() == VIR_ERR_OK) {
             virGenericReportError(domcode, VIR_ERR_XML_ERROR,
diff --git a/src/util/virxml.h b/src/util/virxml.h
index 7af47437bd..03a85bfb25 100644
--- a/src/util/virxml.h
+++ b/src/util/virxml.h
@@ -199,7 +199,8 @@ virXMLParseHelper(int domcode,
                   const char *rootelement,
                   xmlXPathContextPtr *ctxt,
                   const char *schemafile,
-                  bool validate);
+                  bool validate,
+                  bool keepindent);
 
 const char *
 virXMLPickShellSafeComment(const char *str1,
@@ -219,7 +220,17 @@ virXMLPickShellSafeComment(const char *str1,
  * Return the parsed document object, or NULL on failure.
  */
 #define virXMLParse(filename, xmlStr, url, rootelement, ctxt, schemafile, validate) \
-    virXMLParseHelper(VIR_FROM_THIS, filename, xmlStr, url, rootelement, ctxt, schemafile, validate)
+    virXMLParseHelper(VIR_FROM_THIS, filename, xmlStr, url, rootelement, ctxt, schemafile, validate, false)
+
+/**
+ * virXMLParseWithIndent:
+ *
+ * Just like virXMLParse, except indentation is preserved. Should be used when
+ * facing an user provided XML which may be formatted back and keeping verbatim
+ * spacing is necessary (e.g. due to <metadata/>).
+ */
+#define virXMLParseWithIndent(filename, xmlStr, url, rootelement, ctxt, schemafile, validate) \
+    virXMLParseHelper(VIR_FROM_THIS, filename, xmlStr, url, rootelement, ctxt, schemafile, validate, true)
 
 /**
  * virXMLParseStringCtxt:
@@ -233,7 +244,17 @@ virXMLPickShellSafeComment(const char *str1,
  * Return the parsed document object, or NULL on failure.
  */
 #define virXMLParseStringCtxt(xmlStr, url, pctxt) \
-    virXMLParseHelper(VIR_FROM_THIS, NULL, xmlStr, url, NULL, pctxt, NULL, false)
+    virXMLParseHelper(VIR_FROM_THIS, NULL, xmlStr, url, NULL, pctxt, NULL, false, false)
+
+/**
+ * virXMLParseStringCtxtWithIndent:
+ *
+ * Just like virXMLParseStringCtxt, except indentation is preserved.  Should be
+ * used when facing an user provided XML which may be formatted back and
+ * keeping verbatim spacing is necessary (e.g. due to <metadata/>).
+ */
+#define virXMLParseStringCtxtWithIndent(xmlStr, url, pctxt) \
+    virXMLParseHelper(VIR_FROM_THIS, NULL, xmlStr, url, NULL, pctxt, NULL, false, true)
 
 /**
  * virXMLParseFileCtxt:
@@ -246,7 +267,7 @@ virXMLPickShellSafeComment(const char *str1,
  * Return the parsed document object, or NULL on failure.
  */
 #define virXMLParseFileCtxt(filename, pctxt) \
-    virXMLParseHelper(VIR_FROM_THIS, filename, NULL, NULL, NULL, pctxt, NULL, false)
+    virXMLParseHelper(VIR_FROM_THIS, filename, NULL, NULL, NULL, pctxt, NULL, false, false)
 
 int
 virXMLSaveFile(const char *path,
-- 
2.41.0
_______________________________________________
Devel mailing list -- devel@xxxxxxxxxxxxxxxxx
To unsubscribe send an email to devel-leave@xxxxxxxxxxxxxxxxx