Return to HTAnchor.c CVS log

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First version having AA using HTRequest structure.  This seems to work
pretty well with server, but I've been unable to test it with linemode
which doesn't compile currently, so prepare yourself for client
coredumps. :-(  It may also be that AA just simply doesn't let you know
about itself at all -- so it may also appear to be dead instead of
killing the whole client.  Now I'm going home to get some sleep --
staying up 34 hours is starting to get to me.

/*	Hypertext "Anchor" Object				HTAnchor.c
**	==========================
**
** An anchor represents a region of a hypertext document which is linked to
** another anchor in the same or a different document.
**
** History
**
**         Nov 1990  Written in Objective-C for the NeXT browser (TBL)
**	24-Oct-1991 (JFG), written in C, browser-independant 
**	21-Nov-1991 (JFG), first complete version
**
**	(c) Copyright CERN 1991 - See Copyright.html
*/

#define HASH_SIZE 101		/* Arbitrary prime. Memory/speed tradeoff */

#include <ctype.h>
#include "tcp.h"
#include "HTFormat.h"
#include "HTAnchor.h"

#include "HTUtils.h"
#include "HTParse.h"
#include "HTFWriter.h"	/* for cache stuff */

typedef struct _HyperDoc Hyperdoc;
#ifdef VMS
struct _HyperDoc {
	int junk;	/* VMS cannot handle pointers to undefined structs */
};
#endif

PRIVATE HTList **adult_table=0;  /* Point to table of lists of all parents */

/*				Creation Methods
**				================
**
**	Do not use "new" by itself outside this module. In order to enforce
**	consistency, we insist that you furnish more information about the
**	anchor you are creating : use newWithParent or newWithAddress.
*/

PRIVATE HTParentAnchor * HTParentAnchor_new
  NOARGS
{
  HTParentAnchor *newAnchor = 
    (HTParentAnchor *) calloc (1, sizeof (HTParentAnchor));  /* zero-filled */
  newAnchor->parent = newAnchor;
  return newAnchor;
}

PRIVATE HTChildAnchor * HTChildAnchor_new
  NOARGS
{
  return (HTChildAnchor *) calloc (1, sizeof (HTChildAnchor));  /* zero-filled */
}


/*	Case insensitive string comparison
**	----------------------------------
** On entry,
**	s	Points to one string, null terminated
**	t	points to the other.
** On exit,
**	returns	YES if the strings are equivalent ignoring case
**		NO if they differ in more than  their case.
*/

PRIVATE BOOL equivalent
  ARGS2 (CONST char *,s, CONST char *,t)
{
  if (s && t) {  /* Make sure they point to something */
    for ( ; *s && *t ; s++, t++) {
        if (TOUPPER(*s) != TOUPPER(*t))
	  return NO;
    }
    return TOUPPER(*s) == TOUPPER(*t);
  } else
    return s == t;  /* Two NULLs are equivalent, aren't they ? */
}


/*	Create new or find old sub-anchor
**	---------------------------------
**
**	Me one is for a new anchor being edited into an existing
**	document. The parent anchor must already exist.
*/

PUBLIC HTChildAnchor * HTAnchor_findChild
  ARGS2 (HTParentAnchor *,parent, CONST char *,tag)
{
  HTChildAnchor *child;
  HTList *kids;

  if (! parent) {
    if (TRACE) printf ("HTAnchor_findChild called with NULL parent.\n");
    return NULL;
  }
  if ((kids = parent->children)) {  /* parent has children : search them */
    if (tag && *tag) {		/* TBL */
	while ((child = HTList_nextObject (kids))) {
	    if (equivalent(child->tag, tag)) { /* Case sensitive 920226 */
		if (TRACE) fprintf (stderr,
	       "Child anchor %p of parent %p with name `%s' already exists.\n",
		    (void*)child, (void*)parent, tag);
		return child;
	    }
	}
     }  /*  end if tag is void */
  } else  /* parent doesn't have any children yet : create family */
    parent->children = HTList_new ();

  child = HTChildAnchor_new ();
  if (TRACE) fprintf(stderr, "new Anchor %p named `%s' is child of %p\n",
       (void*)child, (int)tag ? tag : (CONST char *)"" , (void*)parent); /* int for apollo */
  HTList_addObject (parent->children, child);
  child->parent = parent;
  StrAllocCopy(child->tag, tag);
  return child;
}


/*	Create or find a child anchor with a possible link
**	--------------------------------------------------
**
**	Create new anchor with a given parent and possibly
**	a name, and possibly a link to a _relatively_ named anchor.
**	(Code originally in ParseHTML.h)
*/
PUBLIC HTChildAnchor * HTAnchor_findChildAndLink
  ARGS4(
       HTParentAnchor *,parent,	/* May not be 0 */
       CONST char *,tag,	/* May be "" or 0 */
       CONST char *,href,	/* May be "" or 0 */
       HTLinkType *,ltype	/* May be 0 */
       )
{
  HTChildAnchor * child = HTAnchor_findChild(parent, tag);
  if (href && *href) {
    char * relative_to = HTAnchor_address((HTAnchor *) parent);
    char * parsed_address = HTParse(href, relative_to, PARSE_ALL);
    HTAnchor * dest = HTAnchor_findAddress(parsed_address);
    HTAnchor_link((HTAnchor *) child, dest, ltype);
    free(parsed_address);
    free(relative_to);
  }
  return child;
}


/*	Create new or find old named anchor
**	-----------------------------------
**
**	Me one is for a reference which is found in a document, and might
**	not be already loaded.
**	Note: You are not guaranteed a new anchor -- you might get an old one,
**	like with fonts.
*/

HTAnchor * HTAnchor_findAddress
  ARGS1 (CONST char *,address)
{
  char *tag = HTParse (address, "", PARSE_ANCHOR);  /* Anchor tag specified ? */

  /* If the address represents a sub-anchor, we recursively load its parent,
     then we create a child anchor within that document. */
  if (*tag) {
    char *docAddress = HTParse(address, "", PARSE_ACCESS | PARSE_HOST |
			                    PARSE_PATH | PARSE_PUNCTUATION);
    HTParentAnchor * foundParent =
      (HTParentAnchor *) HTAnchor_findAddress (docAddress);
    HTChildAnchor * foundAnchor = HTAnchor_findChild (foundParent, tag);
    free (docAddress);
    free (tag);
    return (HTAnchor *) foundAnchor;
  }
  
  else { /* If the address has no anchor tag, 
	    check whether we have this node */
    int hash;
    CONST char *p;
    HTList * adults;
    HTList *grownups;
    HTParentAnchor * foundAnchor;

    free (tag);
    
    /* Select list from hash table */
    for(p=address, hash=0; *p; p++)
    	hash = (hash * 3 + (*(unsigned char*)p))
    	 % HASH_SIZE;
    if (!adult_table)
        adult_table = (HTList**) calloc(HASH_SIZE, sizeof(HTList*));
    if (!adult_table[hash]) adult_table[hash] = HTList_new();
    adults = adult_table[hash];

    /* Search list for anchor */
    grownups = adults;
    while ((foundAnchor = HTList_nextObject (grownups))) {
       if (equivalent(foundAnchor->address, address)) {
	if (TRACE) fprintf(stderr, "Anchor %p with address `%s' already exists.\n",
			  (void*) foundAnchor, address);
	return (HTAnchor *) foundAnchor;
      }
    }
    
    /* Node not found : create new anchor */
    foundAnchor = HTParentAnchor_new ();
    if (TRACE) fprintf(stderr, "New anchor %p has hash %d and address `%s'\n",
    	(void*)foundAnchor, hash, address);
    StrAllocCopy(foundAnchor->address, address);
    HTList_addObject (adults, foundAnchor);
    return (HTAnchor *) foundAnchor;
  }
}


/*	Delete an anchor and possibly related things (auto garbage collection)
**	--------------------------------------------
**
**	The anchor is only deleted if the corresponding document is not loaded.
**	All outgoing links from parent and children are deleted, and this anchor
**	is removed from the sources list of all its targets.
**	We also try to delete the targets whose documents are not loaded.
**	If this anchor's source list is empty, we delete it and its children.
*/

PRIVATE void deleteLinks
  ARGS1 (HTAnchor *,me)
{
  if (! me)
    return;

  /* Recursively try to delete target anchors */
  if (me->mainLink.dest) {
    HTParentAnchor *parent = me->mainLink.dest->parent;
    HTList_removeObject (parent->sources, me);
    if (! parent->document)  /* Test here to avoid calling overhead */
      HTAnchor_delete (parent);
  }
  if (me->links) {  /* Extra destinations */
    HTLink *target;
    while ((target = HTList_removeLastObject (me->links))) {
      HTParentAnchor *parent = target->dest->parent;
      HTList_removeObject (parent->sources, me);
      if (! parent->document)  /* Test here to avoid calling overhead */
	HTAnchor_delete (parent);
    }
  }
}

PUBLIC BOOL HTAnchor_delete
  ARGS1 (HTParentAnchor *,me)
{
  HTChildAnchor *child;

  /* Don't delete if document is loaded */
  if (me->document)
    return NO;

  /* Recursively try to delete target anchors */
  deleteLinks ((HTAnchor *) me);

  if (! HTList_isEmpty (me->sources)) {  /* There are still incoming links */
    /* Delete all outgoing links from children, if any */
    HTList *kids = me->children;
    while ((child = HTList_nextObject (kids)))
      deleteLinks ((HTAnchor *) child);
    return NO;  /* Parent not deleted */
  }

  /* No more incoming links : kill everything */
  /* First, recursively delete children */
  while ((child = HTList_removeLastObject (me->children))) {
    deleteLinks ((HTAnchor *) child);
    free (child->tag);
    free (child);
  }

  /* Now kill myself */
  HTList_delete (me->children);
  HTList_delete (me->sources);
  free (me->address);
  /* Devise a way to clean out the HTFormat if no longer needed (ref count?) */
  free (me);
  if (me->cacheItems) {
      HTCacheClear(me->cacheItems);
  }
  return YES;  /* Parent deleted */
}


/*		Move an anchor to the head of the list of its siblings
**		------------------------------------------------------
**
**	This is to ensure that an anchor which might have already existed
**	is put in the correct order as we load the document.
*/

void HTAnchor_makeLastChild
  ARGS1(HTChildAnchor *,me)
{
  if (me->parent != (HTParentAnchor *) me) {  /* Make sure it's a child */
    HTList * siblings = me->parent->children;
    HTList_removeObject (siblings, me);
    HTList_addObject (siblings, me);
  }
}

/*	Data access functions
**	---------------------
*/

PUBLIC HTParentAnchor * HTAnchor_parent
  ARGS1 (HTAnchor *,me)
{
  return me ? me->parent : NULL;
}

void HTAnchor_setDocument
  ARGS2 (HTParentAnchor *,me, HyperDoc *,doc)
{
  if (me)
    me->document = doc;
}

HyperDoc * HTAnchor_document
  ARGS1 (HTParentAnchor *,me)
{
  return me ? me->document : NULL;
}


/* We don't want code to change an address after anchor creation... yet ?
void HTAnchor_setAddress
  ARGS2 (HTAnchor *,me, char *,addr)
{
  if (me)
    StrAllocCopy (me->parent->address, addr);
}
*/

char * HTAnchor_address
  ARGS1 (HTAnchor *,me)
{
  char *addr = NULL;
  if (me) {
    if (((HTParentAnchor *) me == me->parent) ||
    	!((HTChildAnchor *) me)->tag) {  /* it's an adult or no tag */
      StrAllocCopy (addr, me->parent->address);
    }
    else {  /* it's a named child */
      addr = malloc (2 + strlen (me->parent->address)
		     + strlen (((HTChildAnchor *) me)->tag));
      if (addr == NULL) outofmem(__FILE__, "HTAnchor_address");
      sprintf (addr, "%s#%s", me->parent->address,
	       ((HTChildAnchor *) me)->tag);
    }
  }
  return addr;
}



void HTAnchor_setFormat
  ARGS2 (HTParentAnchor *,me, HTFormat ,form)
{
  if (me)
    me->format = form;
}

HTFormat HTAnchor_format
  ARGS1 (HTParentAnchor *,me)
{
  return me ? me->format : NULL;
}



void HTAnchor_setIndex
  ARGS1 (HTParentAnchor *,me)
{
  if (me)
    me->isIndex = YES;
}

BOOL HTAnchor_isIndex
  ARGS1 (HTParentAnchor *,me)
{
  return me ? me->isIndex : NO;
}



BOOL HTAnchor_hasChildren
  ARGS1 (HTParentAnchor *,me)
{
  return me ? ! HTList_isEmpty(me->children) : NO;
}

/*	Title handling
*/
CONST char * HTAnchor_title
  ARGS1 (HTParentAnchor *,me)
{
  return me ? me->title : 0;
}

void HTAnchor_setTitle
  ARGS2(HTParentAnchor *,me, CONST char *,title)
{
  StrAllocCopy(me->title, title);
}

void HTAnchor_appendTitle
  ARGS2(HTParentAnchor *,me, CONST char *,title)
{
  StrAllocCat(me->title, title);
}

/*	Link me Anchor to another given one
**	-------------------------------------
*/

BOOL HTAnchor_link
  ARGS3(HTAnchor *,source, HTAnchor *,destination, HTLinkType *,type)
{
  if (! (source && destination))
    return NO;  /* Can't link to/from non-existing anchor */
  if (TRACE) printf ("Linking anchor %p to anchor %p\n", source, destination);
  if (! source->mainLink.dest) {
    source->mainLink.dest = destination;
    source->mainLink.type = type;
  } else {
    HTLink * newLink = (HTLink *) malloc (sizeof (HTLink));
    if (newLink == NULL) outofmem(__FILE__, "HTAnchor_link");
    newLink->dest = destination;
    newLink->type = type;
    if (! source->links)
      source->links = HTList_new ();
    HTList_addObject (source->links, newLink);
  }
  if (!destination->parent->sources)
    destination->parent->sources = HTList_new ();
  HTList_addObject (destination->parent->sources, source);
  return YES;  /* Success */
}


/*	Manipulation of links
**	---------------------
*/

HTAnchor * HTAnchor_followMainLink
  ARGS1 (HTAnchor *,me)
{
  return me->mainLink.dest;
}

HTAnchor * HTAnchor_followTypedLink
  ARGS2 (HTAnchor *,me, HTLinkType *,type)
{
  if (me->mainLink.type == type)
    return me->mainLink.dest;
  if (me->links) {
    HTList *links = me->links;
    HTLink *link;
    while ((link = HTList_nextObject (links)))
      if (link->type == type)
	return link->dest;
  }
  return NULL;  /* No link of me type */
}


/*	Make main link
*/
BOOL HTAnchor_makeMainLink
  ARGS2 (HTAnchor *,me, HTLink *,movingLink)
{
  /* Check that everything's OK */
  if (! (me && HTList_removeObject (me->links, movingLink)))
    return NO;  /* link not found or NULL anchor */
  else {
    /* First push current main link onto top of links list */
    HTLink *newLink = (HTLink*) malloc (sizeof (HTLink));
    if (newLink == NULL) outofmem(__FILE__, "HTAnchor_makeMainLink");
    memcpy (newLink, & me->mainLink, sizeof (HTLink));
    HTList_addObject (me->links, newLink);

    /* Now make movingLink the new main link, and free it */
    memcpy (& me->mainLink, movingLink, sizeof (HTLink));
    free (movingLink);
    return YES;
  }
}


/*	Methods List
**	------------
*/

PUBLIC HTList * HTAnchor_methods ARGS1(HTParentAnchor *, me)
{
    if (!me->methods) {
        me->methods = HTList_new();
    }
    return me->methods;
}

/*	Protocol
**	--------
*/

PUBLIC void * HTAnchor_protocol ARGS1(HTParentAnchor *, me)
{
    return me->protocol;
}

PUBLIC void HTAnchor_setProtocol ARGS2(HTParentAnchor *, me,
	void*,	protocol)
{
    me->protocol = protocol;
}

/*	Physical Address
**	----------------
*/

PUBLIC char * HTAnchor_physical ARGS1(HTParentAnchor *, me)
{
    return me->physical;
}

PUBLIC void HTAnchor_setPhysical ARGS2(HTParentAnchor *, me,
	char *,	physical)
{
    StrAllocCopy(me->physical, physical);
}