From 571aac15d8f6d4d33d188df7086e0aa7d7e9cffc Mon Sep 17 00:00:00 2001
From: Steve Lhomme <slhomme@matroska.org>
Date: Sun, 25 Feb 2024 14:35:15 +0100
Subject: [PATCH] spectools: use a callback in EbmlCallbacks to validate the
 size of an element

So it can be checked even before the element is created.
---
 spectool/schema_2_kaxsemantic_cpp.xsl | 11 +++++++++++
 spectool/schema_2_kaxsemantic_h.xsl   | 12 ++++++++----
 2 files changed, 19 insertions(+), 4 deletions(-)

diff --git a/spectool/schema_2_kaxsemantic_cpp.xsl b/spectool/schema_2_kaxsemantic_cpp.xsl
index 19d18ca6..536ae7ca 100644
--- a/spectool/schema_2_kaxsemantic_cpp.xsl
+++ b/spectool/schema_2_kaxsemantic_cpp.xsl
@@ -176,6 +176,17 @@ static constexpr const MatroskaProfile VERSION_WEBM_UP_TO_V4 = {true, false, 0,
                 <xsl:call-template name="output-display-name">
                     <xsl:with-param name="node" select="."/>
                 </xsl:call-template>
+                <xsl:choose>
+                    <xsl:when test="@name='Block' or @name='SimpleBlock' or @name='BlockVirtual'"><xsl:text>, KaxInternalBlock::SizeIsValid</xsl:text></xsl:when>
+                    <xsl:when test="not(@length)"><xsl:text>, libebml::EbmlBinary::SizeIsValid</xsl:text></xsl:when>
+                    <xsl:otherwise>
+                        <xsl:text>, Kax</xsl:text>
+                        <xsl:call-template name="get-class-name">
+                            <xsl:with-param name="node" select="."/>
+                        </xsl:call-template>
+                        <xsl:text>::SizeIsValid</xsl:text>
+                    </xsl:otherwise>
+                </xsl:choose>
                 <xsl:call-template name="output-minmax">
                     <xsl:with-param name="node" select="."/>
                 </xsl:call-template>
diff --git a/spectool/schema_2_kaxsemantic_h.xsl b/spectool/schema_2_kaxsemantic_h.xsl
index 06dc3024..f66c4480 100644
--- a/spectool/schema_2_kaxsemantic_h.xsl
+++ b/spectool/schema_2_kaxsemantic_h.xsl
@@ -67,7 +67,6 @@ namespace libmatroska {
             </xsl:when>
             <xsl:when test="@type='binary'">
                 <xsl:text>DECLARE_MKX_BINARY</xsl:text>
-                <xsl:if test="@length"><xsl:text>_LENGTH</xsl:text></xsl:if>
             </xsl:when>
             <xsl:when test="@type='uinteger'">
                 <xsl:text>DECLARE_MKX_UINTEGER</xsl:text>
@@ -98,9 +97,6 @@ namespace libmatroska {
         <xsl:call-template name="get-class-name">
             <xsl:with-param name="node" select="."/>
         </xsl:call-template>
-        <xsl:if test="@length">
-            <xsl:text>, </xsl:text><xsl:value-of select="@length"/>
-        </xsl:if>
         <xsl:text>)&#10;</xsl:text>
         <xsl:if test="@maxver='0' or @maxver='1' or @maxver='2' or @maxver='3'">
             <xsl:text>public:&#10;</xsl:text>
@@ -108,6 +104,14 @@ namespace libmatroska {
         <xsl:if test="@maxver='0' or @maxver='1' or @maxver='2' or @maxver='3'">
             <xsl:text>  libebml::filepos_t RenderData(libebml::IOCallback &amp; output, bool bForceRender, const ShouldWrite &amp; writeFilter) override;&#10;</xsl:text>
         </xsl:if>
+        <xsl:if test="@length">
+            <xsl:text>  static inline bool SizeIsValid(std::uint64_t Size) {return Size </xsl:text>
+            <xsl:choose>
+                <xsl:when test="contains(@length, '=') or contains(@length, '&lt;') or contains(@length, '&gt;')"><xsl:value-of select="@length"/></xsl:when>
+                <xsl:otherwise><xsl:text>== </xsl:text><xsl:value-of select="@length"/></xsl:otherwise>
+            </xsl:choose>
+            <xsl:text>;}&#10;</xsl:text>
+        </xsl:if>
         <xsl:text>};&#10;</xsl:text>
         <!-- <xsl:if test="$minVer &gt; 1 or ebml:extension[@divx='1']">#endif&#10;</xsl:if> -->
         <xsl:text>&#10;</xsl:text>