context.c

/* $Source: /home/CVSROOT/c2ada/context.c,v $ */
/* $Revision: 1.2 $  $Date: 1999/02/03 19:45:03 $ */

/*
 * The context module defines an abstract data type, ctxt_t, which
 * holds information about the context of a statement or expression
 * being transformed into an Ada-compatible form.  It holds whatever
 * additional declarations, preceding statements, or following (post-)
 * statements are required in the transformation.
 */
#include "c2ada.h"


struct context_t
{
    bool changed_pre : 1;
    bool changed_post : 1;
    bool added_decls : 1;

    symbol_t* decls;
    stmt_pt pre_stmts;
    stmt_pt post_stmts;

    scope_id_t scope;
};

ctxt_pt new_context(scope_id_t scope)
{
    ctxt_pt ctxt = (ctxt_pt)allocate(sizeof(ctxt_t));
    ctxt->scope = scope;
    return ctxt;
}

ctxt_pt copy_context(ctxt_pt ctxt)
{
    ctxt_pt result = new_context(ctxt->scope);
    *result = *ctxt;
    return result;
}

void free_context(ctxt_pt ctxt)
{
    deallocate(ctxt);
}

bool changed_pre(ctxt_pt ctxt)
{
    return ctxt->changed_pre;
}

bool changed_post(ctxt_pt ctxt)
{
    return ctxt->changed_post;
}

bool added_decls(ctxt_pt ctxt)
{
    return ctxt->added_decls;
}

void reset_changed(ctxt_pt ctxt)
{
    ctxt->changed_pre = false;
    ctxt->changed_post = false;
    ctxt->added_decls = false;
}

void clear_pre_and_post(ctxt_pt ctxt)
{
    ctxt->pre_stmts = 0;
    ctxt->post_stmts = 0;
    ctxt->changed_pre = false;
    ctxt->changed_post = false;
}

stmt_pt pre_stmts(ctxt_pt ctxt)
{
    return ctxt->pre_stmts;
}

stmt_pt post_stmts(ctxt_pt ctxt)
{
    return ctxt->post_stmts;
}

void set_pre(ctxt_pt ctxt, stmt_pt stmts)
{
    set_stmts_scope(stmts, ctxt->scope);
    ctxt->pre_stmts = stmts;
}

void set_post(ctxt_pt ctxt, stmt_pt stmts)
{
    set_stmts_scope(stmts, ctxt->scope);
    ctxt->post_stmts = stmts;
}

void append_pre(ctxt_pt ctxt, stmt_pt stmt)
{
    if(!stmt)
        return;
    set_stmts_scope(stmt, ctxt->scope);
    if(ctxt->pre_stmts)
    {
        append_stmt(ctxt->pre_stmts, stmt);
    }
    else
    {
        ctxt->pre_stmts = new_stmt_list(stmt);
    }
    ctxt->changed_pre = true;
}

void append_post(ctxt_pt ctxt, stmt_pt stmt)
{
    if(!stmt)
        return;
    set_stmts_scope(stmt, ctxt->scope);
    if(ctxt->post_stmts)
    {
        append_stmt(ctxt->post_stmts, stmt);
    }
    else
    {
        ctxt->post_stmts = new_stmt_list(stmt);
    }
    ctxt->changed_post = true;
}

static void set_decls_scope(symbol_t* decls, scope_id_t scope)
{
    symbol_t* sym;
    int level = scope_level(scope);
    for(sym = decls; sym; sym = sym->sym_parse_list)
    {
        sym->sym_scope_id = scope;
        sym->sym_scope = level;
    }
}

symbol_t* decls(ctxt_pt ctxt, int scope_id)
{
    if(scope_id)
    {
        /* nonzero scope_id is a signal to change all the scope_ids in the
         * list
         */
        set_decls_scope(ctxt->decls, scope_id);
    }
    return ctxt->decls;
}

void set_decls(ctxt_pt ctxt, symbol_t* decls)
{
    if(!decls)
        return;
    set_decls_scope(decls, ctxt->scope);
    ctxt->decls = decls;
}

void append_decls(ctxt_pt ctxt, symbol_t* decls)
{
    if(!decls)
        return;
    set_decls_scope(decls, ctxt->scope);
    ctxt->decls = concat_symbols(ctxt->decls, decls);
    ctxt->added_decls = true;
}

void append_decl(ctxt_pt ctxt, symbol_t* decl)
{
    append_decls(ctxt, decl);
}

scope_id_t ctxt_scope(ctxt_pt ctxt)
{
    return ctxt->scope;
}