Libguestfs - Sep 2011 - [PATCH 6/7] hivexml: Report attributes in values instead of text.

Reporting value data in attributes has two advantages:
* The output of hivexml breaks Python expat processing if binary data
makes it out.  This was observed in Software hives.
* Not having child text makes room for child elements.

Signed-off-by: Alex Nelson <ajnelson at cs.ucsc.edu>
---
 xml/hivexml.c |   25 ++++++++++++++++++++-----
 1 files changed, 20 insertions(+), 5 deletions(-)

diff --git a/xml/hivexml.c b/xml/hivexml.c
index f29c80c..4789dbc 100644
--- a/xml/hivexml.c
+++ b/xml/hivexml.c
@@ -199,6 +199,7 @@ node_start (hive_h *h, void *writer_v, hive_node_h node,
const char *name)
 {
   int64_t last_modified;
   char *timebuf;
+  int ret = 0;
 
   xmlTextWriterPtr writer = (xmlTextWriterPtr) writer_v;
   XML_CHECK (xmlTextWriterStartElement, (writer, BAD_CAST "node"));
@@ -278,7 +279,9 @@ value_string (hive_h *h, void *writer_v, hive_node_h node,
hive_value_h value,
   }
 
   start_value (writer, key, type, NULL);
-  XML_CHECK (xmlTextWriterWriteString, (writer, BAD_CAST str));
+  XML_CHECK (xmlTextWriterStartAttribute, (writer, BAD_CAST
"value"));
+  XML_CHECK (xmlTextWriterWriteString, (writer, str));
+  XML_CHECK (xmlTextWriterEndAttribute, (writer));
   end_value (writer);
   return 0;
 }
@@ -332,7 +335,9 @@ value_string_invalid_utf16 (hive_h *h, void *writer_v,
hive_node_h node,
   }
 
   start_value (writer, key, type, "base64");
+  XML_CHECK (xmlTextWriterStartAttribute, (writer, BAD_CAST
"value"));
   XML_CHECK (xmlTextWriterWriteBase64, (writer, str, 0, len));
+  XML_CHECK (xmlTextWriterEndAttribute, (writer));
   end_value (writer);
 
   return 0;
@@ -344,7 +349,7 @@ value_dword (hive_h *h, void *writer_v, hive_node_h node,
hive_value_h value,
 {
   xmlTextWriterPtr writer = (xmlTextWriterPtr) writer_v;
   start_value (writer, key, "int32", NULL);
-  XML_CHECK (xmlTextWriterWriteFormatString, (writer, "%" PRIi32,
v));
+  XML_CHECK (xmlTextWriterWriteFormatAttribute, (writer, BAD_CAST
"value", "%" PRIi32, v));
   end_value (writer);
   return 0;
 }
@@ -355,7 +360,7 @@ value_qword (hive_h *h, void *writer_v, hive_node_h node,
hive_value_h value,
 {
   xmlTextWriterPtr writer = (xmlTextWriterPtr) writer_v;
   start_value (writer, key, "int64", NULL);
-  XML_CHECK (xmlTextWriterWriteFormatString, (writer, "%" PRIi64,
v));
+  XML_CHECK (xmlTextWriterWriteFormatAttribute, (writer, "value",
"%" PRIi64, v));
   end_value (writer);
   return 0;
 }
@@ -366,7 +371,9 @@ value_binary (hive_h *h, void *writer_v, hive_node_h node,
hive_value_h value,
 {
   xmlTextWriterPtr writer = (xmlTextWriterPtr) writer_v;
   start_value (writer, key, "binary", "base64");
+  XML_CHECK (xmlTextWriterStartAttribute, (writer, BAD_CAST
"value"));
   XML_CHECK (xmlTextWriterWriteBase64, (writer, v, 0, len));
+  XML_CHECK (xmlTextWriterEndAttribute, (writer));
   end_value (writer);
   return 0;
 }
@@ -377,7 +384,11 @@ value_none (hive_h *h, void *writer_v, hive_node_h node,
hive_value_h value,
 {
   xmlTextWriterPtr writer = (xmlTextWriterPtr) writer_v;
   start_value (writer, key, "none", "base64");
-  if (len > 0) XML_CHECK (xmlTextWriterWriteBase64, (writer, v, 0, len));
+  if (len > 0) {
+    XML_CHECK (xmlTextWriterStartAttribute, (writer, BAD_CAST
"value"));
+    XML_CHECK (xmlTextWriterWriteBase64, (writer, v, 0, len));
+    XML_CHECK (xmlTextWriterEndAttribute, (writer));
+  }
   end_value (writer);
   return 0;
 }
@@ -410,7 +421,11 @@ value_other (hive_h *h, void *writer_v, hive_node_h node,
hive_value_h value,
   }
 
   start_value (writer, key, type, "base64");
-  if (len > 0) XML_CHECK (xmlTextWriterWriteBase64, (writer, v, 0, len));
+  if (len > 0) {
+    XML_CHECK (xmlTextWriterStartAttribute, (writer, BAD_CAST
"value"));
+    XML_CHECK (xmlTextWriterWriteBase64, (writer, v, 0, len));
+    XML_CHECK (xmlTextWriterEndAttribute, (writer));
+  }
   end_value (writer);
 
   return 0;
-- 
1.7.6

On Thu, Sep 01, 2011 at 06:17:43PM -0700, Alex Nelson
wrote:
> Reporting value data in attributes has two advantages:
> * The output of hivexml breaks Python expat processing if binary data
> makes it out.  This was observed in Software hives.
> * Not having child text makes room for child elements.
ACK, pushed 4 of the patches now.

BTW please run 'make check' and test all the bindings.  I had to fix
the OCaml bindings, and a mistake in errno handling in hivex_value_key
was revealed by 'make check'.

Rich.

-- 
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