/* * $Id: ext_hdr.c,v 1.1.1.1 2002/03/28 00:02:52 andrew_belov Exp $ * --------------------------------------------------------------------------- * Handy functions for dealing with extended headers. * */#include "arj.h"DEBUGHDR(__FILE__)                      /* Debug information block *//* Allocates a per-file extended header structure */struct ext_hdr FAR *eh_alloc(){ struct ext_hdr FAR *rc; rc=(struct ext_hdr FAR *)farmalloc_msg(sizeof(struct ext_hdr)); far_memset((char FAR *)rc, 0, sizeof(struct ext_hdr)); return(rc);}/* Locates a block with the specified tag, returning pointer to it */struct ext_hdr FAR *eh_lookup(struct ext_hdr FAR *eh, char tag){ while(eh->next!=NULL) {  if(eh->tag==tag)   return(eh);  eh=eh->next; } return(NULL);}/* Locates an unfinalized block */struct ext_hdr FAR *eh_find_pending(struct ext_hdr FAR *eh){ if(eh==NULL)  return(NULL); while(eh->next!=NULL) {  if(EH_STATUS(eh)!=EH_FINALIZED)   return(eh);  eh=eh->next; } return(NULL);}/* Inserts a new block into an instantiated extended header structure. If the   block is given as NULL, performs reallocation only */struct ext_hdr FAR *eh_append(struct ext_hdr FAR *eh, char tag, char FAR *block, unsigned int size){ struct ext_hdr FAR *p_eh; if((p_eh=eh_lookup(eh, tag))==NULL) {  for(p_eh=eh; p_eh->next!=NULL; p_eh=p_eh->next);  p_eh->tag=tag;  p_eh->next=eh_alloc(); } p_eh->raw=(char FAR *)farrealloc_msg(p_eh->raw, p_eh->size+size); if(block!=NULL)  far_memmove(p_eh->raw+p_eh->size, block, size); p_eh->size+=size; return(p_eh);}/* Releases the extended header structure */void eh_release(struct ext_hdr FAR *eh){ struct ext_hdr FAR *p_eh; while((p_eh=eh->next)!=NULL) {  if(eh->raw!=NULL)   farfree(eh->raw);  farfree(eh);  eh=p_eh; }}