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ASSEMBLY & COMPILE TOOLS/PLM-2-C 2/plm2c/context.c

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+#include "misc.h"
+#include "defs.h"
+#include "cvt.h"
+#include "struct.h"
+
+/*
+ *	Pointer to the current context
+ */
+CONTEXT		*context_head;
+/*
+ *	Pointer to all popped contexts
+ */
+CONTEXT		*old_context;
+
+/*
+ *	Search DECL_MEMBER list for symbol and if found, return TRUE
+ *	and pointer to DECL_ID for that symbol.
+ */
+find_member_symbol(symbol, decl_ptr, decl_id)
+TOKEN		*symbol;
+DECL_MEMBER	*decl_ptr;
+DECL_ID		**decl_id;
+{
+	DECL_ID	*var_ptr;
+
+	for (var_ptr = decl_ptr->name_list; var_ptr;
+			var_ptr = var_ptr->next_var) {
+		if (!strcmp(var_ptr->name->token_name, symbol->token_name)) {
+			*decl_id = var_ptr;
+			return TRUE;
+		}
+	}
+	*decl_id = NULL;
+	return FALSE;
+}
+
+/*
+ *	Search DECL_MEMBER list for symbol.
+ *	If found, return pointer to DECL_MEMBER containing that symbol
+ *	in decl_found, and return TRUE.
+ *	If not found, return null pointer in decl_found, and return FALSE.
+ */
+find_list_symbol(symbol, decl_ptr, decl_found, decl_id)
+TOKEN		*symbol;
+DECL_MEMBER	*decl_ptr, **decl_found;
+DECL_ID		**decl_id;
+{
+	for (*decl_found = decl_ptr; *decl_found;
+			*decl_found = (*decl_found)->next_member) {
+		if (find_member_symbol(symbol, *decl_found, decl_id))
+			return TRUE;
+	}
+	return FALSE;
+}
+
+/*
+ *	Search context for symbol.
+ *	If found, return pointer to DECL_MEMBER containing that symbol
+ *	in decl_found, return DECL_ID for that symbol in decl_id, and
+ *	return TRUE.
+ *	If not found, return null pointers in decl_found and decl_id,
+ *	and return FALSE.
+ */
+find_symbol(symbol, decl_found, decl_id)
+TOKEN		*symbol;
+DECL_MEMBER	**decl_found;
+DECL_ID		**decl_id;
+{
+	CONTEXT	*context_ptr;
+
+	for (context_ptr = context_head; context_ptr;
+			context_ptr = context_ptr->next_context) {
+		if (find_list_symbol(symbol, context_ptr->decl_head,
+				decl_found, decl_id))
+			return TRUE;
+	}
+	return FALSE;
+}
+
+/*
+ *	Add a declaration to current context
+ */
+add_to_context(decl)
+DECL_MEMBER	*decl;
+{
+	DECL_MEMBER	*decl_ptr;
+
+		/* Find end of declaration list */
+	for (decl_ptr = decl; decl_ptr->next_member; )
+		decl_ptr = decl_ptr->next_member;
+
+		/* Add current declarations to tail of new list */
+	decl_ptr->next_member = context_head->decl_head;
+	context_head->decl_head = decl;
+}
+
+/*
+ *	Add a DECL list to context and NULL the list pointer
+ */
+add_decl_to_context(decl)
+DECL	*decl;
+{
+	DECL	*decl_ptr;
+
+		/* Find end of declaration list */
+	for (decl_ptr = decl; decl_ptr; decl_ptr = decl_ptr->next_decl) {
+		if (decl_ptr->decl_list)
+			add_to_context(decl_ptr->decl_list);
+		decl_ptr->decl_list = NULL;
+	}
+}
+
+/*
+ *	Push a new context of specified type and name
+ */
+new_context(type, name)
+int	type;
+TOKEN	*name;
+{
+	CONTEXT	*new_context;
+
+	get_context_ptr(&new_context);
+	new_context->context_type = type;
+	if (name) {
+		get_token_ptr(&new_context->context_name);
+		token_copy(name, new_context->context_name);
+	} else
+		new_context->context_name = NULL;
+	new_context->next_context = context_head;
+	context_head = new_context;
+}
+
+/*
+ *	Pop current context and place on old context
+ */
+pop_context()
+{
+	CONTEXT	*popped_context;
+
+	popped_context = context_head;
+	context_head = popped_context->next_context;
+	popped_context->next_context = old_context;
+	old_context = popped_context;
+}
+
+/*
+ *	Initializes context pointers
+ */
+init_context()
+{
+	context_head = NULL;
+	old_context = NULL;
+}
+