1 files changed, 146 insertions, 0 deletions
diff --git a/src/rexmpp_roster.c b/src/rexmpp_roster.c
new file mode 100644
index 0000000..8479c14
--- /dev/null
+++ b/src/rexmpp_roster.c
@@ -0,0 +1,146 @@
+/**
+   @file rexmpp_roster.c
+   @brief Roster-related functions.
+   @author defanor <defanor@uberspace.net>
+   @date 2020
+   @copyright MIT license.
+*/
+
+#include "rexmpp.h"
+#include <syslog.h>
+#include <string.h>
+#include <libxml/tree.h>
+#include <libxml/xmlsave.h>
+
+xmlNodePtr rexmpp_roster_find_item (rexmpp_t *s,
+                                    const char *jid,
+                                    xmlNodePtr *prev_item)
+{
+  xmlNodePtr prev = NULL, cur = s->roster_items;
+  while (cur != NULL) {
+    char *cur_jid = xmlGetProp(cur, "jid");
+    if (cur_jid == NULL) {
+      rexmpp_log(s, LOG_ALERT, "No jid found in a roster item.");
+      return NULL;
+    }
+    int match = (strcmp(cur_jid, jid) == 0);
+    free(cur_jid);
+    if (match) {
+      if (prev_item != NULL) {
+        *prev_item = prev;
+      }
+      return cur;
+    }
+    prev = cur;
+    cur = cur->next;
+  }
+  return NULL;
+}
+
+rexmpp_err_t rexmpp_modify_roster (rexmpp_t *s, xmlNodePtr item) {
+  rexmpp_err_t ret = REXMPP_SUCCESS;
+  if (! rexmpp_xml_match(item, "jabber:iq:roster", "item")) {
+    rexmpp_log(s, LOG_ERR, "No roster item.");
+    return REXMPP_E_PARAM;
+  }
+  char *subscription = xmlGetProp(item, "subscription");
+  char *jid = xmlGetProp(item, "jid");
+  if (subscription != NULL && strcmp(subscription, "remove") == 0) {
+    /* Delete the item. */
+    xmlNodePtr prev, cur;
+    cur = rexmpp_roster_find_item(s, jid, &prev);
+    if (cur != NULL) {
+      if (prev != NULL) {
+        prev->next = cur->next;
+      } else {
+        s->roster_items = cur->next;
+      }
+      xmlFreeNode(cur);
+    } else {
+      ret = REXMPP_E_ROSTER_ITEM_NOT_FOUND;
+    }
+  } else {
+    /* Add or modify the item. */
+    xmlNodePtr cur, prev;
+    cur = rexmpp_roster_find_item(s, jid, &prev);
+    /* Remove the item if it was in the roster before. */
+    if (cur != NULL) {
+      if (prev != NULL) {
+        prev->next = cur->next;
+      } else {
+        s->roster_items = cur->next;
+      }
+      xmlFreeNode(cur);
+    }
+    /* Add the new item. */
+    xmlNodePtr new_item = xmlCopyNode(item, 1);
+    new_item->next = s->roster_items;
+    s->roster_items = new_item;
+  }
+  free(jid);
+  if (subscription != NULL) {
+    free(subscription);
+  }
+  return ret;
+}
+
+void rexmpp_roster_set (rexmpp_t *s, xmlNodePtr query) {
+  if (s->roster_items != NULL) {
+    xmlFreeNodeList(s->roster_items);
+  }
+  if (s->roster_ver != NULL) {
+    free(s->roster_ver);
+  }
+  s->roster_ver = xmlGetProp(query, "ver");
+  s->roster_items = xmlCopyNodeList(xmlFirstElementChild(query));
+}
+
+void rexmpp_roster_cache_read (rexmpp_t *s) {
+  if (s->roster_cache_file == NULL) {
+    rexmpp_log(s, LOG_WARNING, "No roster cache file path is set.");
+    return;
+  }
+  xmlDocPtr doc = xmlReadFile(s->roster_cache_file, "utf-8", XML_PARSE_NONET);
+  xmlNodePtr query = xmlDocGetRootElement(doc);
+  rexmpp_roster_set(s, query);
+  xmlFreeDoc(doc);
+}
+
+void rexmpp_roster_cache_write (rexmpp_t *s) {
+  if (s->roster_cache_file == NULL) {
+    rexmpp_log(s, LOG_WARNING, "No roster cache file path is set.");
+    return;
+  }
+  xmlDocPtr doc = xmlNewDoc("1.0");
+  xmlNodePtr query = xmlNewDocNode(doc, NULL, "query", NULL);
+  xmlDocSetRootElement(doc, query);
+  xmlNewNs(query, "jabber:iq:roster", NULL);
+  if (s->roster_ver != NULL) {
+    xmlNewProp(query, "ver", s->roster_ver);
+  }
+  if (s->roster_items != NULL) {
+    xmlAddChild(query, xmlDocCopyNodeList(doc, s->roster_items));
+  }
+  xmlSaveFileEnc(s->roster_cache_file, doc, "utf-8");
+  xmlFreeDoc(doc);
+}
+
+void rexmpp_iq_roster_get (rexmpp_t *s,
+                           xmlNodePtr req,
+                           xmlNodePtr response,
+                           int success)
+{
+  if (! success) {
+    rexmpp_log(s, LOG_ERR, "Roster loading failed.");
+    return;
+  }
+  xmlNodePtr query = xmlFirstElementChild(response);
+  if (! rexmpp_xml_match(query, "jabber:iq:roster", "query")) {
+    rexmpp_log(s, LOG_DEBUG, "No roster query in reply.");
+    return;
+  }
+  rexmpp_roster_set(s, query);
+  if (s->roster_cache_file != NULL) {
+    rexmpp_roster_cache_write(s);
+  }
+}