swig/Source/Swig/fragment.c

/* ----------------------------------------------------------------------------- 
 * fragment.c
 *
 *     This file manages named code fragments.  Code fragments are typically
 *     used to hold helper-code that may or may not be included in the wrapper
 *     file (depending on what features are actually used in the interface).
 *
 *     By using fragments, it's possible to greatly reduce the amount of
 *     wrapper code and to generate cleaner wrapper files. 
 * 
 * Author(s) : David Beazley (beazley@cs.uchicago.edu)
 *
 * Copyright (C) 1999-2000.  The University of Chicago
 * See the file LICENSE for information on usage and redistribution.	
 * ----------------------------------------------------------------------------- */

char cvsroot_fragment_c[] = "$Header$";

#include "swig.h"

static Hash *fragments = 0;
static int debug = 0;


/* -----------------------------------------------------------------------------
 * Swig_fragment_register()
 *
 * Add a fragment. Use the original Node*, so, if something needs to be
 * changed, lang.cxx doesn't nedd to be touched again.
 * ----------------------------------------------------------------------------- */

void
Swig_fragment_register(Node* fragment) {
  if (Getattr(fragment,"emitonly")) {
    Swig_fragment_emit(fragment);
    return;
  } else {
    String *name = Copy(Getattr(fragment,"value"));
    String *type = Getattr(fragment,"type");
    if (type) {
      SwigType *rtype = SwigType_typedef_resolve_all(type);
      String *mangle = Swig_string_mangle(rtype);
      Append(name,mangle);
      Delete(mangle);
      Delete(rtype);
    }
    if (debug) Printf(stdout,"register fragment %s %s\n",name,type);
    if (!fragments) {
      fragments = NewHash();
    }
    if (!Getattr(fragments,name)) {
      String *section = Copy(Getattr(fragment,"section"));
      String *ccode = Copy(Getattr(fragment,"code"));
      Hash *kwargs = Getattr(fragment,"kwargs");
      Setmeta(ccode,"section",section);
      if (kwargs) {
	kwargs = Copy(kwargs);
	Setmeta(ccode,"kwargs",kwargs);
	Delete(kwargs);      
      }
      Setattr(fragments,name,ccode);
      if (debug) Printf(stdout,"registering fragment %s %s\n",name,section);
      Delete(section);
      Delete(ccode);
    }
  }
}

/* -----------------------------------------------------------------------------
 * Swig_fragment_emit()
 *
 * Emit a fragment
 * ----------------------------------------------------------------------------- */

static
char* char_index(char* str, char c)
{
  while (*str && (c != *str)) ++str;
  return (c == *str) ? str : 0;
}

void
Swig_fragment_emit(Node *n) {
  String *code;
  char   *pc, *tok;
  String *t;
  String *mangle = 0;
  String *name = 0;
  String *type = 0;

  if (!fragments) return;

  name = Getattr(n,"value");
  if (!name) {
    name = n;
  }
  type = Getattr(n,"type");
  if (type) {
    SwigType *rtype = SwigType_typedef_resolve_all(type);
    mangle = Swig_string_mangle(rtype);
    Delete(rtype);
  }

  if (debug) Printf(stdout,"looking fragment %s %s\n",name, type);
  t = Copy(name);
  tok = Char(t);
  pc = char_index(tok,',');
  if (pc) *pc = 0;
  while (tok) {
    String *name = NewString(tok);
    if (mangle) Append(name,mangle);
    code = Getattr(fragments,name);
    if (debug) Printf(stdout,"looking subfragment %s\n", name);
    if (code && (Strcmp(code,"ignore") != 0)) {
      String *section = Getmeta(code,"section");
      Hash *n = Getmeta(code,"kwargs");
      while (n) {
	if (Cmp(Getattr(n,"name"),"fragment") == 0) {
	  if (debug) Printf(stdout,"emitting fragment %s %s\n",n, type);
	  Swig_fragment_emit(n);
	}
	n = nextSibling(n);
      }
      if (section) {
	File *f = Swig_filebyname(section);
	if (!f) {
	  Swig_error(Getfile(code),Getline(code),
		     "Bad section '%s' for code fragment '%s'\n", section,name);
	} else {
	  if (debug) Printf(stdout,"emitting subfragment %s %s\n",name, section);
	  if (debug) Printf(f,"/* begin fragment %s */\n",name);
	  Printf(f,"%s\n",code);
	  if (debug) Printf(f,"/* end fragment %s */\n\n",name);
	  Setattr(fragments,name,"ignore");
	}
      }
    }
    tok = pc ? pc + 1 : 0;
    if (tok) {
      pc = char_index(tok,',');
      if (pc) *pc = 0;
    }
  }
  Delete(t);
}