/*************************************************************************
 *                  
 *       (c) Copyright 1992 - 1995 by G & A Technical Software, Inc.,
 *             28 Research Drive, Hampton, Virginia, 23666.
 *
 *   All Rights Reserved. No part of this software or publication may be
 *   reproduced, stored in a retrieval system, or transmitted, in any form
 *   or by any means, electronic, mechanical, photocopying, recording, or
 *   otherwise without the prior written permission of G & A Technical
 *   Software, Inc.
 *  
 *************************************************************************
 *
 * Filename: s3_dynamic_module_load.c
 *
 * Purpose:  Provides the ability to dynamically load modules where 
 *           O/S provides necessary support. Currently supports two
 *           methods of dynamic loading, GNU dld and dlopen/dlclose/etc
 *           for ELF based systems.
 *
 * Author:   John Burton
 *
 * Date:     5/31/94
 *
 *************************************************************************
 *
 * Modification History:
 *
 * $Log$
 *
 *************************************************************************
 *
 * Revision Control Information:
 */
   static char rcsid[]  = "$Id$";
   static char rcsrev[] = "$Revision$";

#include "s3_machdep.h"
#include "s3_defines.h"
#include "s3_typedefs.h"
#include "s3_externals.h"
#include "s3_globals.h"

#include <dlfcn.h>

typedef struct mlstruct {
  char            *name;
  char            *file;
  struct mlstruct *next;
} Mod_list;


static Mod_list *Modules = NULL;

static int is_in(char c, char *s)
{
  while(*s)
    if(*s++ == c) 
      return 1;
  return 0;
}

int s3_dml_init (char *path)
{
}


extern File_list *lib_list;

void s3_load_dynamic_modules(EMT_struct *emt_info)
{
  int       i,result,len;
  ST_entry *entry;
  char     *tmp,*name;
  File_list *curr;
  void      *vptr = NULL;
  extern char      *shapplib;
  extern File_list *s3_GetLibList();

  curr = s3_GetLibList();
  fprintf(fperr,"Loading Dynamic Modules from %s ",shapplib);

  for(i=0;i<emt_info->nexe;i++)
    {
      entry = emt_info->exe_list[i];
      name = strsave(entry->en.name);
#ifdef _F2C_SUFFIX
      if((entry->en.type == FFUNC)||(entry->en.type == FSUBR))
	 {
	   if(is_in('_',entry->en.name))
	     name = strsave2(name,"__");
	   else
	     name = strcat(name,"_");
	 }
#endif
      if((entry->en.vptr = dlopen(entry->en.filename,RTLD_NOW)) == NULL)
	 s3_error(SYS,"s3_load_dynamic_modules - dlopen: %s",dlerror());
      if((entry->en.function = (int (*)()) dlsym(entry->en.vptr,name)) == NULL)
	 {
           fprintf(fperr,"s3_load_dynamic_modules - dlsym returned NULL => %s\n",name);
         if ((tmp = dlerror()) != NULL)
	    s3_error(SYS,"s3_load_dynamic_modules - dlsym: %s => %s",tmp,name);
	 }
      xfree(name);
    }
  fprintf(fperr," done\n");
}

		  
void s3_dml_unload_symbol(char *symbol)
{
  
}

void s3_unload_dynamic_modules(EMT_struct *emt_info)
{
  int       i,result;
  ST_entry *entry;
  char     tmp[80];
  File_list *curr;
  extern File_list *s3_GetLibList();

  curr = s3_GetLibList();
  fprintf(fperr,"Unloading Dynamic Modules ");
  for(i=0;i<emt_info->nexe;i++)
    {
      fprintf(fperr,".");
      entry = emt_info->exe_list[i];
      dlclose(entry->en.vptr);
    }
  fprintf(fperr," done\n");
}



void s3_compile_dynamic_modules(EMT_struct *emt_info)
{
  int  len, ulen, result, i;
  ST_entry *entry;
  char *tmp,*name;
  extern char *uliblist;
  extern char *applib;
  char *dloadflags = D_LOADFLAGS;
  char *compiler;

  uliblist = (uliblist == NULL) ? strdup(" ") : uliblist;
  ulen = (uliblist != NULL) ? strlen(uliblist) : 0;
  len = strlen(Cflags) + strlen(applib) + ulen + strlen(dloadflags) + 80;
  tmp = (char *)xmalloc(len*sizeof(char));
  fprintf(fperr,"Compiling Dynamic Modules ");
  /*
  for(i=0;i<emt_info->nexe;i++)
    {
      fprintf(fperr,".");
      entry = emt_info->exe_list[i];
      name = strsave(entry->en.name);
      if((entry->en.type == FFUNC)||(entry->en.type == FSUBR))
	 {
	   compiler = F_COMPILER;
#ifdef _F2C_SUFFIX
	   if(is_in('_',name))
	     name = stringcat(name,"__");
	   else
	     name = stringcat(name,"_");
#endif
	 }
      else
	 compiler = C_COMPILER;
#ifdef _USE_S3_DL
      sprintf(tmp,"%s %s -o %s -bM:SRE -e %s %s %s %s >> %s",compiler
              Cflags,entry->en.filename,entry->en.name,applib,uliblist,D_LOADFLAGS,logfile); 
#else
      sprintf(tmp,"%s -shared -rdynamic %s -o %s -u %s -L./shlibs -l%s %s %s & >>%s",
	      compiler,Cflags,entry->en.filename,name,progname,uliblist,dloadflags,logfile); 
#endif
      result = system(tmp);
      if(result < 0)
	s3_error(SYS,"s3_compile_dynamic_modules: fork or exec system call failed for command %s",tmp);
      if(result > 0)
	s3_error(SYS,"s3_compile_dynamic_modules: system call returned %d for command %s",result,tmp);
      xfree(name);
    }
    */ 
  fprintf(fperr," done\n");
  xfree(tmp);
}


void s3_put_file_module(char * name)
{
  char nm_command[80];
  char dummy[80];
  char symbol[80];
  FILE* pipe;
  int        result;
  Mod_list  *tmp;

  
  strcpy(nm_command,"nm -p ");
  strcat(nm_command,name);
  pipe = popen(nm_command,"r");
  while (!feof(pipe)) 
    {
      fgets(dummy,80,pipe);
      strcpy(symbol,&dummy[8]); 
      if (!strncmp(symbol," T ",3))
	{
	  symbol[strlen(symbol) - 1] = '\0';
 	  tmp = (Mod_list *)xmalloc(sizeof(Mod_list));
	  tmp->name = strsave(&symbol[4]);
	  tmp->file = strsave(name);
          tmp->next = Modules;
	  Modules   = tmp;
	}
    }
  result = pclose(pipe);
}
 

char *s3_get_module_file(char *name)
{
  Mod_list *tmp;
  char     *filename;
  int       result;

  tmp = Modules;
  while((tmp != NULL)&&((result = strcmp(name,tmp->name)) != 0))
    {
      tmp = tmp->next;
    }
  if(tmp != NULL)
    return tmp->file;
  else
    return NULL;
}