SERVER-51856 Add Visual Studio Natvis debugger visualizers for BSONObj and BSONElement

3 files changed, 363 insertions, 0 deletions

diff --git a/buildscripts/win/mongodb.natvis b/buildscripts/win/mongodb.natvis
index 7e6a6bfb854..047b4ccb747 100644
--- a/buildscripts/win/mongodb.natvis
+++ b/buildscripts/win/mongodb.natvis
@@ -32,6 +32,335 @@
     <StringView>_data,[_size]s8</StringView>
   </Type>
 
+  <Type Name="mongo::BSONElementBinaryType">
+    <DisplayString>{{ binary, size={size} }}</DisplayString>
+    <Expand>
+      <Item Name="size">size</Item>
+      <Item Name="subtype">(mongo::BinDataType)subtype</Item>
+      <Item Name="data">(uint8_t*)this+5,[size]x</Item>
+    </Expand>
+  </Type>
+
+  <Type Name="mongo::BSONElementRegexType">
+    <DisplayString>{{ {this,s8}, {this+strlen((char*)this)+1,s8} }}</DisplayString>
+    <Expand>
+      <Item Name="pattern">(const char*)this,s8</Item>
+      <Item Name="options">(const char*)this+strlen((char*)this)+1,s8</Item>
+    </Expand>
+  </Type>
+
+  <Type Name="mongo::BSONElementDBRefType">
+    <DisplayString>{{ {this+4,[*(int32_t*)this-1]s8} }}</DisplayString>
+    <Expand>
+      <CustomListItems>
+        <Item Name="{this+4,[*(int32_t*)this-1]s8}">*(mongo::OID*)(this+*(int32_t*)this+4)</Item>
+      </CustomListItems>
+    </Expand>
+  </Type>
+
+  <Type Name="mongo::BSONElementCodeWithScopeType">
+    <DisplayString>{{ {this+8,[*(int32_t*)(this+4)-1]s8} }}</DisplayString>
+    <Expand>
+      <CustomListItems>
+        <Variable Name="Code" InitialValue="(const char*)this+4"/>
+        
+        <Item Name="code">Code+4,[*(int32_t*)(Code)-1]s8</Item>
+        <Item Name="scope">*(mongo::BSONObjData*)(Code+*(int32_t*)(Code)+4)</Item>
+      </CustomListItems>
+    </Expand>
+  </Type>
+
+  <!-- 
+  It it not possible to use variables to calculate contents in the DisplayString nodes.
+  
+  this+strlen((char*)&amp;name)+2: Skips over the type byte and the name with its null terminator to get to the beginning of the value
+  -->
+  <Type Name="mongo::BSONElementData">
+    <!-- double: { name, value } -->
+    <DisplayString Condition="type==1">{*(double*)((char*)this+strlen(&amp;name)+2)}</DisplayString>
+
+    <!-- string -->
+    <DisplayString Condition="type==2 ">{(char*)this+strlen(&amp;name)+6,[*(int32_t*)((char*)this+strlen(&amp;name)+2)-1]s8}</DisplayString>
+
+    <!-- embedded document or array -->
+    <DisplayString Condition="type==3 || type==4">objsize={*(int32_t*)((char*)this+strlen(&amp;name)+2)}</DisplayString>
+
+    <!-- binary, treat uuid separately -->
+    <DisplayString Condition="type==5 &amp;&amp; *(char*)((char*)this+strlen((char*)&amp;name)+6)!=4">binary</DisplayString>
+    <DisplayString Condition="type==5 &amp;&amp; *(char*)((char*)this+strlen((char*)&amp;name)+6)==4">uuid</DisplayString>
+
+    <!-- undefined -->
+    <DisplayString Condition="type==6">undefined</DisplayString>
+
+    <!-- ObjectId -->
+    <DisplayString Condition="type==7">oid</DisplayString>
+
+    <!-- bool -->
+    <DisplayString Condition="type==8">{*(bool*)((char*)this+strlen((char*)&amp;name)+2)}</DisplayString>
+
+    <!-- Date_t -->
+    <DisplayString Condition="type==9">{*(mongo::Date_t*)((char*)this+strlen((char*)&amp;name)+2)}</DisplayString>
+
+    <!-- null -->
+    <DisplayString Condition="type==10">null</DisplayString>
+
+    <!-- regex -->
+    <DisplayString Condition="type==11">regex</DisplayString>
+
+    <!-- DBRef -->
+    <DisplayString Condition="type==12 ">DBRef</DisplayString>
+
+    <!-- Code -->
+    <DisplayString Condition="type==13 ">code</DisplayString>
+
+    <!-- Symbol -->
+    <DisplayString Condition="type==14 ">symbol</DisplayString>
+
+    <!-- code with scope -->
+    <DisplayString Condition="type==15">codeWScope</DisplayString>
+
+    <!-- int32 -->
+    <DisplayString Condition="type==16">{*(int32_t*)((char*)this+strlen((char*)&amp;name)+2)}</DisplayString>
+
+    <!-- Timestamp -->
+    <DisplayString Condition="type==17">{*(mongo::Timestamp*)((char*)this+strlen((char*)&amp;name)+2)}</DisplayString>
+
+    <!-- int64 -->
+    <DisplayString Condition="type==18">{*(int64_t*)((char*)this+strlen((char*)&amp;name)+2)}</DisplayString>
+
+    <!-- Decimal128 -->
+    <DisplayString Condition="type==19">{*(mongo::Decimal128*)((char*)this+strlen((char*)&amp;name)+2)}</DisplayString>
+
+    <!-- MinKey/MaxKey -->
+    <DisplayString Condition="type==-1">MinKey</DisplayString>
+    <DisplayString Condition="type==0x7f">MaxKey</DisplayString>
+
+    <Expand>
+      <CustomListItems>
+        <Variable Name="DataType" InitialValue="*(signed char*)this" />
+        <Variable Name="DataName" InitialValue="(const char*)&amp;name"/>
+        <Variable Name="DataValue" InitialValue="DataName+strlen(DataName)+1"/>
+        <Variable Name="BinarySubType" InitialValue="*(uint8_t*)(DataValue+4)"/>
+
+        <Item Name="value" Condition="DataType==1">*(double*)DataValue</Item>
+        <Item Name="value" Condition="DataType==2 || DataType==13 || DataType==14">DataValue+4,[*DataValue-1]s8</Item>
+        <Item Name="value" Condition="DataType==3">*(mongo::BSONObjData*)DataValue</Item>
+        <Item Name="value" Condition="DataType==4">*(mongo::BSONArrayData*)DataValue</Item>
+        <Item Name="value" Condition="DataType==5 &amp;&amp; BinarySubType!=4 ">*(mongo::BSONElementBinaryType*)DataValue</Item>
+        <Item Name="value" Condition="DataType==5 &amp;&amp; BinarySubType==4 ">*(mongo::UUID*)(DataValue+5)</Item>
+        <Item Name="value" Condition="DataType==7">*(mongo::OID*)DataValue</Item>
+        <Item Name="value" Condition="DataType==8">*(bool*)DataValue</Item>
+        <Item Name="value" Condition="DataType==9">*(mongo::Date_t*)DataValue</Item>
+        <Item Name="value" Condition="DataType==11">*(mongo::BSONElementRegexType*)DataValue</Item>
+        <Item Name="value" Condition="DataType==12">*(mongo::BSONElementDBRefType*)DataValue</Item>
+        <Item Name="value" Condition="DataType==15">*(mongo::BSONElementCodeWithScopeType*)DataValue</Item>
+        <Item Name="value" Condition="DataType==16">*(int32_t*)DataValue</Item>
+        <Item Name="value" Condition="DataType==17">*(mongo::Timestamp*)DataValue</Item>
+        <Item Name="value" Condition="DataType==18">*(int64_t*)DataValue</Item>
+        <Item Name="value" Condition="DataType==19">*(mongo::Decimal128*)DataValue</Item>
+      </CustomListItems>
+    </Expand>
+  </Type>
+
+  <Type Name="mongo::BSONElement">
+    <!-- double: { name, value } -->
+    <DisplayString Condition="*(char*)data==1">{{ {data+1,s8}, {*(double*)((char*)data+strlen(data+1)+2)} }}</DisplayString>
+
+    <!-- string -->
+    <DisplayString Condition="*(char*)data==2 ">{{ {data+1,s8}, {(char*)data+strlen(data+1)+6,[*(int32_t*)((char*)data+strlen(data+1)+2)-1]s8} }}</DisplayString>
+
+    <!-- embedded document or array -->
+    <DisplayString Condition="*(char*)data==3 || *(char*)data==4">{{ {data+1,s8}, objsize={*(int32_t*)((char*)data+strlen(data+1)+2)} }}</DisplayString>
+
+    <!-- binary, treat uuid separately -->
+    <DisplayString Condition="*(char*)data==5 &amp;&amp; *(char*)((char*)data+strlen((char*)data+1)+6)!=4">{{ {data+1,s8}, binary }}</DisplayString>
+    <DisplayString Condition="*(char*)data==5 &amp;&amp; *(char*)((char*)data+strlen((char*)data+1)+6)==4">{{ {data+1,s8}, uuid }}</DisplayString>
+
+    <!-- undefined -->
+    <DisplayString Condition="*(char*)data==6">{{ {data+1,s8}, undefined }}</DisplayString>
+
+    <!-- ObjectId -->
+    <DisplayString Condition="*(char*)data==7">{{ {data+1,s8}, oid }}</DisplayString>
+
+    <!-- bool -->
+    <DisplayString Condition="*(char*)data==8">{{ {data+1,s8}, {*(bool*)((char*)data+strlen((char*)data+1)+2)} }}</DisplayString>
+
+    <!-- Date_t -->
+    <DisplayString Condition="*(char*)data==9">{{ {data+1,s8}, {*(mongo::Date_t*)((char*)data+strlen((char*)data+1)+2)} }}</DisplayString>
+
+    <!-- null -->
+    <DisplayString Condition="*(char*)data==10">{{ {data+1,s8}, null }}</DisplayString>
+
+    <!-- regex -->
+    <DisplayString Condition="*(char*)data==11">{{ {data+1,s8}, regex }}</DisplayString>
+
+    <!-- DBRef -->
+    <DisplayString Condition="*(char*)data==12 ">{{ {data+1,s8}, DBRef }}</DisplayString>
+
+    <!-- Code -->
+    <DisplayString Condition="*(char*)data==13 ">{{ {data+1,s8}, code }}</DisplayString>
+
+    <!-- Symbol -->
+    <DisplayString Condition="*(char*)data==14 ">{{ {data+1,s8}, symbol }}</DisplayString>
+
+    <!-- code with scope -->
+    <DisplayString Condition="*(char*)data==15">{{ {data+1,s8}, codeWScope }}</DisplayString>
+
+    <!-- int32 -->
+    <DisplayString Condition="*(char*)data==16">{{ {data+1,s8}, {*(int32_t*)((char*)data+strlen((char*)data+1)+2)} }}</DisplayString>
+
+    <!-- Timestamp -->
+    <DisplayString Condition="*(char*)data==17">{{ {data+1,s8}, {*(mongo::Timestamp*)((char*)data+strlen((char*)data+1)+2)} }}</DisplayString>
+
+    <!-- int64 -->
+    <DisplayString Condition="*(char*)data==18">{{ {data+1,s8}, {*(int64_t*)((char*)data+strlen((char*)data+1)+2)} }}</DisplayString>
+
+    <!-- Decimal128 -->
+    <DisplayString Condition="*(char*)data==19">{{ {data+1,s8}, {*(mongo::Decimal128*)((char*)data+strlen((char*)data+1)+2)} }}</DisplayString>
+
+    <!-- MinKey/MaxKey -->
+    <DisplayString Condition="*(char*)data==-1">{{ {data+1,s8}, MinKey }}</DisplayString>
+    <DisplayString Condition="*(char*)data==0x7f">{{ {data+1,s8}, MaxKey }}</DisplayString>
+    
+    <Expand>
+        <Item Name="name">(const char*)data+1,s8</Item>
+        <Item Name="value">(const mongo::BSONElementData*)data,na</Item>
+    </Expand>
+  </Type>
+
+  <Type Name="mongo::BSONObjData">
+    <DisplayString>{{ objsize={size} }}</DisplayString>
+    <Expand>
+      <CustomListItems>
+        <Variable Name="DataPointer" InitialValue="(const char*)this"/>
+        <Variable Name="ItemType" InitialValue="(int32_t)0" />
+        <Variable Name="ItemName" InitialValue="(const char*)nullptr" />
+        <Variable Name="ItemValue" InitialValue="(const char*)nullptr" />
+
+        <Exec>DataPointer += 4</Exec>
+        <Loop>
+          <Break Condition="*DataPointer == 0"/>
+          <Exec>ItemType=*DataPointer</Exec>
+          <Exec>ItemName=DataPointer+1</Exec>
+          <Item Name="{ItemName,s8}">(const mongo::BSONElementData*)DataPointer,na</Item>
+          <Exec>DataPointer=ItemName+strlen(ItemName)+1</Exec>
+          <!-- double, Date_t, Timestamp, 64bit integer -->
+          <If Condition="ItemType==1 || ItemType==9 || ItemType==17 || ItemType==18">
+            <Exec>DataPointer+=8</Exec>
+          </If>
+          <!-- string types: string, DBPointer, JavaScript, Symbol-->
+          <If Condition="ItemType==2 || ItemType==13 || ItemType==14 || ItemType==12">
+            <Exec>DataPointer+=*(int32_t*)DataPointer+4</Exec>
+          </If>
+          <!-- types beginning with an int for size: embedded document, embedded array, codeWithScope -->
+          <If Condition="ItemType==3 || ItemType==4 || ItemType==15">
+            <Exec>DataPointer+=*(int32_t*)DataPointer</Exec>
+          </If>
+          <!-- binary -->
+          <If Condition="ItemType==5">
+            <Exec>DataPointer+=*(int32_t*)DataPointer+5</Exec>
+          </If>
+          <!-- ObjectId, DBPointer -->
+          <If Condition="ItemType==7 || ItemType==12">
+            <Exec>DataPointer+=12</Exec>
+          </If>
+          <!-- bool -->
+          <If Condition="ItemType==8">
+            <Exec>DataPointer+=1</Exec>
+          </If>
+          <!-- regular expression -->
+          <If Condition="ItemType==11">
+            <Exec>DataPointer+=strlen(DataPointer)+1</Exec>
+            <Exec>DataPointer+=strlen(DataPointer)+1</Exec>
+          </If>
+          <!-- 32bit integer -->
+          <If Condition="ItemType==16">
+            <Exec>DataPointer+=4</Exec>
+          </If>
+          <!-- Decimal128 -->
+          <If Condition="ItemType==19">
+            <Exec>DataPointer+=16</Exec>
+          </If>
+        </Loop>
+        <Item Name="[size]">size</Item>
+      </CustomListItems>
+    </Expand>
+  </Type>
+
+  <!-- Same as BSONObjData but skip field names -->
+  <Type Name="mongo::BSONArrayData">
+    <DisplayString>{{ arrsize={size} }}</DisplayString>
+    <Expand>
+      <CustomListItems>
+        <Variable Name="DataPointer" InitialValue="(const char*)this"/>
+        <Variable Name="ItemType" InitialValue="(int32_t)0" />
+        <Variable Name="ItemName" InitialValue="(const char*)nullptr" />
+        <Variable Name="ItemValue" InitialValue="(const char*)nullptr" />
+
+        <Exec>DataPointer += 4</Exec>
+        <Loop>
+          <Break Condition="*DataPointer == 0"/>
+          <Exec>ItemType=*DataPointer</Exec>
+          <Exec>ItemName=DataPointer+1</Exec>
+          <Item>(const mongo::BSONElementData*)DataPointer,na</Item>
+          <Exec>DataPointer=ItemName+strlen(ItemName)+1</Exec>
+          <!-- double, Date_t, Timestamp, 64bit integer -->
+          <If Condition="ItemType==1 || ItemType==9 || ItemType==17 || ItemType==18">
+            <Exec>DataPointer+=8</Exec>
+          </If>
+          <!-- string types: string, DBPointer, JavaScript, Symbol-->
+          <If Condition="ItemType==2 || ItemType==13 || ItemType==14 || ItemType==12">
+            <Exec>DataPointer+=*(int32_t*)DataPointer+4</Exec>
+          </If>
+          <!-- types beginning with an int for size: embedded document, embedded array, codeWithScope -->
+          <If Condition="ItemType==3 || ItemType==4 || ItemType==15">
+            <Exec>DataPointer+=*(int32_t*)DataPointer</Exec>
+          </If>
+          <!-- binary -->
+          <If Condition="ItemType==5">
+            <Exec>DataPointer+=*(int32_t*)DataPointer+5</Exec>
+          </If>
+          <!-- ObjectId, DBPointer -->
+          <If Condition="ItemType==7 || ItemType==12">
+            <Exec>DataPointer+=12</Exec>
+          </If>
+          <!-- bool -->
+          <If Condition="ItemType==8">
+            <Exec>DataPointer+=1</Exec>
+          </If>
+          <!-- regular expression -->
+          <If Condition="ItemType==11">
+            <Exec>DataPointer+=strlen(DataPointer)+1</Exec>
+            <Exec>DataPointer+=strlen(DataPointer)+1</Exec>
+          </If>
+          <!-- 32bit integer -->
+          <If Condition="ItemType==16">
+            <Exec>DataPointer+=4</Exec>
+          </If>
+          <!-- Decimal128 -->
+          <If Condition="ItemType==19">
+            <Exec>DataPointer+=16</Exec>
+          </If>
+        </Loop>
+        <Item Name="[size]">size</Item>
+      </CustomListItems>
+    </Expand>
+  </Type>
+
+  <Type Name="mongo::BSONObj">
+    <DisplayString>objsize={*(int32_t*)_objdata}</DisplayString>
+    <Expand>
+      <ExpandedItem>(const mongo::BSONObjData*)_objdata</ExpandedItem>
+    </Expand>
+  </Type>
+
+  <Type Name="mongo::BSONArray">
+    <DisplayString>objsize={*(int32_t*)_objdata}</DisplayString>
+    <Expand>
+      <ExpandedItem>(const mongo::BSONArrayData*)_objdata</ExpandedItem>
+    </Expand>
+  </Type>
+
   <Type Name="absl::container_internal::raw_hash_set&lt;*&gt;">
     <DisplayString>{{ size={size_} }}</DisplayString>
     <Expand>
diff --git a/src/mongo/bson/bsonelement.cpp b/src/mongo/bson/bsonelement.cpp
index 312eb849caf..d93f928861c 100644
--- a/src/mongo/bson/bsonelement.cpp
+++ b/src/mongo/bson/bsonelement.cpp
@@ -971,4 +971,25 @@ bool BSONObj::coerceVector(std::vector<T>* out) const {
     return true;
 }
 
+/**
+ * Types used to represent BSONElement memory in the Visual Studio debugger
+ */
+#if defined(_MSC_VER) && defined(_DEBUG)
+struct BSONElementData {
+    char type;
+    char name;
+} bsonElementDataInstance;
+
+struct BSONElementBinaryType {
+    int32_t size;
+    uint8_t subtype;
+} bsonElementBinaryType;
+struct BSONElementRegexType {
+} bsonElementRegexType;
+struct BSONElementDBRefType {
+} bsonElementDBPointerType;
+struct BSONElementCodeWithScopeType {
+} bsonElementCodeWithScopeType;
+#endif  // defined(_MSC_VER) && defined(_DEBUG)
+
 }  // namespace mongo
diff --git a/src/mongo/bson/bsonobj.cpp b/src/mongo/bson/bsonobj.cpp
index 48a3102b605..f606cb7d13b 100644
--- a/src/mongo/bson/bsonobj.cpp
+++ b/src/mongo/bson/bsonobj.cpp
@@ -819,4 +819,17 @@ BSONObjIteratorSorted::BSONObjIteratorSorted(const BSONObj& object)
 BSONArrayIteratorSorted::BSONArrayIteratorSorted(const BSONArray& array)
     : BSONIteratorSorted(array, ElementFieldCmp(true)) {}
 
+/**
+ * Types used to represent BSONObj and BSONArray memory in the Visual Studio debugger
+ */
+#if defined(_MSC_VER) && defined(_DEBUG)
+struct BSONObjData {
+    int32_t size;
+} bsonObjDataInstance;
+
+struct BSONArrayData {
+    int32_t size;
+} bsonObjArrayInstance;
+#endif  // defined(_MSC_VER) && defined(_DEBUG)
+
 }  // namespace mongo