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- /* 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 "HTAnchor.h"
- #include "HTUtils.h"
- #include "HTParse.h"
-
- typedef struct _HyperDoc Hyperdoc;
-
- 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 && *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);
- 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);
- }
-