diff options
Diffstat (limited to 'lnode.c')
| -rw-r--r-- | lnode.c | 168 |
1 files changed, 110 insertions, 58 deletions
@@ -5,7 +5,7 @@ /*----------------------------------------------------------------------------*/ /*Based on the code of unionfs translator.*/ /*----------------------------------------------------------------------------*/ -/*Copyright (C) 2001, 2002, 2005 Free Software Foundation, Inc. +/*Copyright (C) 2001, 2002, 2005, 2008 Free Software Foundation, Inc. Written by Sergiu Ivanov <unlimitedscolobb@gmail.com>. This program is free software; you can redistribute it and/or @@ -29,6 +29,7 @@ /*----------------------------------------------------------------------------*/ #include "lnode.h" #include "debug.h" +#include "node.h" /*----------------------------------------------------------------------------*/ /*----------------------------------------------------------------------------*/ @@ -138,9 +139,19 @@ lnode_destroy /*Destroy the name of the node*/ free(node->name); - /*If there is a list of translators*/ - if(node->trans) - free(node->trans); + /*While the list of proxies has not been freed*/ + node_list_t p; + for(p = node->proxies; p;) + { + /*shift the pointer to the head of the list forward*/ + node->proxies = node->proxies->next; + + /*drop the current cell in the list*/ + free(p); + + /*store the current proxy*/ + p = node->proxies; + } /*Destroy the node itself*/ free(node); @@ -307,70 +318,111 @@ lnode_uninstall node->next->prevp = &node->next; }/*lnode_uninstall*/ /*----------------------------------------------------------------------------*/ -/*Constructs a list of translators that were set on the ancestors of `node`*/ +/*Makes the specified lnode aware of another proxy. Both `node` and `proxy` + must be locked*/ error_t -lnode_list_translators +lnode_add_proxy ( lnode_t * node, - char ** trans, /*the malloced list of 0-separated strings*/ - size_t * ntrans /*the number of elements in `trans`*/ + node_t * proxy ) { - /*The size of block of memory for the list of translators*/ - size_t sz = 0; - - /*Used for tracing the lineage of `node`*/ - lnode_t * ln = node; - - /*Used in computing the lengths of lists of translators in every node - we will go through and for constructing the final list of translators*/ - char * p; - - /*The current position in *data (used in filling out the list of - translators)*/ - char * transp; - - /*The length of the current translator name*/ - size_t complen; - - size_t i; - - /*Trace the lineage of the `node` (including itself) and compute the - total length of the list of translators*/ - for(; ln; sz += ln->translen, ln = ln->dir); - - /*Try to allocate a block of memory sufficient for storing the list of - translators*/ - *trans = malloc(sz); - if(!*trans) + /*TODO: Make the list of proxies finite*/ + + /*Create an new cell in the list of proxies*/ + node_list_t p = malloc(sizeof(node_list_t)); + if(!p) return ENOMEM; + + /*If the supplied node references an lnode already + (this should always happen, though)*/ + if(proxy->nn->lnode) + /*remove the reference held by the node to that lnode*/ + lnode_ref_remove(proxy->nn->lnode); + + /*Connect the proxy to the lnode*/ + proxy->nn->lnode = node; + + /*Store the pointer to the proxy in the new cell*/ + p->node = proxy; + + /*Add the new cell to the list of proxies*/ + p->next = node->proxies; + node->proxies = p; - /*No translators at first*/ - *ntrans = 0; + /*Count a new reference to this lnode*/ + lnode_ref_add(node); - /*Again trace the lineage of the `node` (including itself)*/ - for(transp = *trans + sz, ln = node; ln; ln = ln->dir) + /*Everything is OK here*/ + return 0; + }/*lnode_add_proxy*/ +/*----------------------------------------------------------------------------*/ +/*Removes the specified proxy from the list of proxies of the supplied lnode. + `proxy` must not be locked*/ +void +lnode_remove_proxy + ( + lnode_t * node, + node_t * proxy + ) + { + /*A pointer to a cell in the list of proxies*/ + node_list_t p; + + /*Lock the lnode*/ + mutex_lock(&node->lock); + + /*If the first cell in the list contains a reference to `proxy`*/ + if(node->proxies->node == proxy) { - /*Go through each translator name in the list of names*/ - for(i = 0, p = ln->trans + ln->translen - 2; i < ln->ntrans; ++i) - { - /*position p at the beginning of the current component and - compute its length at the same time*/ - for(complen = 0; *p; --p, ++complen); - --p; - - /*move the current position backwards*/ - transp -= complen + 1; + /*store a pointer to the head of the list*/ + p = node->proxies; + + /*shift the head of the list forward*/ + node->proxies = node->proxies->next; + + /*destroy the former head*/ + free(p); + + /*remove a reference from the supplied lnode*/ + lnode_ref_remove(node); + + /*stop right here*/ + mutex_unlock(&node->lock); + return; + } - /*copy the current translator name into the list*/ - strcpy(transp, p + 2); - - /*we've got another translator*/ - ++*ntrans; - } + /*Another pointer to a cell in the list*/ + node_list_t q; + + /*Go through the list of proxy nodes of the given lnode*/ + for(p = node->proxies; p->next; p = p->next) + { + /*If the next cell does not contain a reference to the same node, + as specified in the parameter, skip this entry*/ + if(p->next->node != proxy) + continue; + + /*store a copy of the next element*/ + q = p->next; + + /*unregister the next element from the list*/ + p->next = q->next; + + /*remove the unregistered element*/ + free(q); + + /*stop looping*/ + break; } + + /*Remove a reference from the supplied lnode*/ + lnode_ref_remove(node); - /*Everything OK*/ - return 0; - }/*lnode_list_translators*/ + + /*Unlock the node*/ + mutex_unlock(&node->lock); + + return; + }/*lnode_remove_proxy*/ /*----------------------------------------------------------------------------*/ |