From b63f05e87b3e87159077a88b22132829fd2928f4 Mon Sep 17 00:00:00 2001
From: dcw <d.white@imperial.ac.uk>
Date: Fri, 30 May 2014 17:28:05 +0100
Subject: [PATCH] added experimental free support, triggered by -f flag (sets
 makefree variable)

---
 datadec.c |   3 ++
 decs.c    | 146 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 decs.h    |   2 +
 3 files changed, 151 insertions(+)

diff --git a/datadec.c b/datadec.c
index 1c49203..4e40507 100644
--- a/datadec.c
+++ b/datadec.c
@@ -62,6 +62,9 @@ int main( int argc, char **argv )
 			case 'v':
 				verbose = TRUE;
 				break;
+			case 'f':
+				makefree = TRUE;
+				break;
 			case 'n':
 				opt = FALSE;
 				break;
diff --git a/decs.c b/decs.c
index 79fc6cc..e2c2a98 100644
--- a/decs.c
+++ b/decs.c
@@ -5,6 +5,7 @@
 #include "struct.h"
 #include "decs.h"
 
+BOOL makefree = FALSE;
 
 static void literalline( char * mesg );
 static void h_declns( char * base, char * exports, BOOL init, declnlist d );
@@ -28,6 +29,11 @@ static void print_fns( declnlist d );
 static void print_fn_shape( declnlist d, shapelist s );
 static void print_all_params( declnlist d, shapelist s );
 static void print_param( shapelist s, paramlist p, BOOL Union );
+static void free_fn_proto( char * name, BOOL prot );
+static void free_fns( declnlist d );
+static void free_fn_shape( declnlist d, shapelist s );
+static void free_all_params( declnlist d, shapelist s );
+static void free_param( shapelist s, paramlist p, BOOL Union );
 
 
 static int numtabs = 0;
@@ -179,6 +185,10 @@ static void c_declns( char *base, char *globals, char *begin, declnlist d )
 	cons_fns( d );
 	decons_fns( d );
 	print_fns( d );
+	if( makefree )
+	{
+		free_fns( d );
+	}
 
 	if( *globalptr != '\0' )
 	{
@@ -382,6 +392,10 @@ static void proto_type( decln d, BOOL prot )
 		}
 	}
 	print_fn_proto( d->name, prot );
+	if( makefree )
+	{
+		free_fn_proto( d->name, prot );
+	}
 }
 
 
@@ -880,3 +894,135 @@ static void print_param( shapelist s, paramlist p, BOOL Union )
 		line( "print_%s( f, %s );", p->type, pname );
 	}
 }
+
+
+/* ------------------- experimental free functions ------------------------ */
+
+
+static void free_fn_proto( char *name, BOOL prot )
+{
+	fprintf( outfile, "extern void free_%s(", name );
+	if( prot )
+	{
+		fprintf( outfile, " %s ", name );
+	}
+	fputs( ");\n", outfile );
+}
+
+
+static void free_fns( declnlist d )
+{
+	for( ; d != NULL; d = d->next )
+	{
+		shapelist s;
+
+		line( "void free_%s( %s p )",d->name, d->name );
+		line( "{" );
+		indent();
+		s = d->shapes;
+		if( d->UseNull )
+		{
+			line( "if( p == NULL )" );
+			line( "{" );
+			indent();
+			line( "return;" );
+			outdent();
+			line( "}" );
+			s = s->next;
+		}
+		if( d->TagField )
+		{
+			line( "switch( p->tag )" );
+			line( "{" );
+			for( ; s != NULL; s = s->next )
+			{
+				free_fn_shape( d, s );
+			}
+			line( "default:" );
+			indent();
+			line( "fprintf( stderr," );
+			line( " \"free_%s: impossible tag %%d\\n\", p->tag );",
+				d->name );
+			line( "exit(1);" );
+			outdent();
+			line( "}" );
+		}
+		else if( ! d->TagField && d->Struct )	/* one shape left */
+		{
+			free_all_params( d, s );
+		}
+		else if( ! d->Struct && d->ManyShapes ) /* enumerated type */
+		{
+			line( "switch( p )" );
+			line( "{" );
+			for( ; s != NULL; s = s->next )
+			{
+				line( "case %s_%s():", d->name, s->name );
+				indent();
+				free_all_params( d, s );
+				line( "break;" );
+				outdent();
+			}
+			line( "}" );
+		} else
+		{
+			fprintf( stderr,
+				 "datadec: internal error in free_fns\n" );
+			exit(1);
+		}
+		if( d->Struct )		/* now need to free the node itself */
+		{
+			line( "free( p );" );
+		}
+		outdent();
+		line( "}\n\n" );
+	}
+}
+
+
+static void free_fn_shape( declnlist d, shapelist s )
+{
+	line( "case %s_is_%s:", d->name, s->name );
+	indent();
+	free_all_params( d, s );
+	line( "break;" );
+	outdent();
+}
+
+
+static void free_all_params( declnlist d, shapelist s )
+{
+	paramlist	p;
+
+	for( p = s->params; p != NULL; p = p->next )
+	{
+		free_param( s, p, d->Union );
+	}
+}
+
+
+static void free_param( shapelist s, paramlist p, BOOL Union )
+{
+	char pname[200];
+
+	if( Union )
+	{
+		if( s->params->next == NULL )
+		{
+			/* no internal struct */
+			sprintf( pname, "p->u.%s_%s", s->name, p->name );
+		} else
+		{
+			/* internal struct */
+			sprintf( pname, "p->u.%s.%s", s->name, p->name );
+		}
+	} else
+	{
+		sprintf( pname, "p->%s", p->name );
+	}
+
+	if( ! p->dontfree )
+	{
+		line( "free_%s( %s );", p->type, pname );
+	}
+}
diff --git a/decs.h b/decs.h
index 4717e9a..55ccd49 100644
--- a/decs.h
+++ b/decs.h
@@ -1 +1,3 @@
+extern BOOL makefree;
+
 extern void make_declns( char * , char * , char * , declnlist , char * );
-- 
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