From c2c1aa8b94024803f623575c5f9ea89d9317f1e0 Mon Sep 17 00:00:00 2001
From: Dave West <davew@uncensored.citadel.org>
Date: Tue, 10 Nov 2009 19:27:46 +0000
Subject: [PATCH] Grabbed another chunk of code out of user_ops.c, purge_user()
 This chunk checked if a user was logged in by testing the user numbers It is
 now a function and exposed to the API as int CtdlIsUserLoggedInByNum(int num)
 Also marked the code with a FIXME since it is unsafe, a user could log in
 after the test but before the delete and realy mess things up.

---
 citadel/context.c             | 26 ++++++++++++++++++++++++++
 citadel/include/ctdl_module.h |  1 +
 citadel/user_ops.c            | 22 +++++++++++-----------
 3 files changed, 38 insertions(+), 11 deletions(-)

diff --git a/citadel/context.c b/citadel/context.c
index 3122e5c06..478ed03ad 100644
--- a/citadel/context.c
+++ b/citadel/context.c
@@ -151,6 +151,32 @@ int CtdlIsUserLoggedIn (char *user_name)
 	return ret;
 }
 
+
+
+/*
+ * Check to see if a user is currently logged in.
+ * Basically same as CtdlIsUserLoggedIn() but uses the user number instead.
+ * Take care with what you do as a result of this test.
+ * The user may not have been logged in when this function was called BUT
+ * because of threading the user might be logged in before you test the result.
+ */
+int CtdlIsUserLoggedInByNum (int usernum)
+{
+	CitContext *cptr;
+	int ret = 0;
+
+	begin_critical_section(S_SESSION_TABLE);
+	for (cptr = ContextList; cptr != NULL; cptr = cptr->next) {
+		if (cptr->user.usernum == usernum) {
+			ret = 1;
+		}
+	}
+	end_critical_section(S_SESSION_TABLE);
+	return ret;
+}
+
+
+
 /*
  * Return a pointer to the CitContext structure bound to the thread which
  * called this function.  If there's no such binding (for example, if it's
diff --git a/citadel/include/ctdl_module.h b/citadel/include/ctdl_module.h
index 5e7488794..5ec05ab08 100644
--- a/citadel/include/ctdl_module.h
+++ b/citadel/include/ctdl_module.h
@@ -190,6 +190,7 @@ int CtdlIsSingleUser(void);
 
 
 int CtdlIsUserLoggedIn (char *user_name);
+int CtdlIsUserLoggedInByNum (int usernum);
 
 
 /*
diff --git a/citadel/user_ops.c b/citadel/user_ops.c
index 965cec625..67935a34f 100644
--- a/citadel/user_ops.c
+++ b/citadel/user_ops.c
@@ -1027,8 +1027,6 @@ int purge_user(char pname[])
 	char filename[64];
 	struct ctdluser usbuf;
 	char usernamekey[USERNAME_SIZE];
-	CitContext *ccptr;
-	int user_is_logged_in = 0;
 
 	makeuserkey(usernamekey, pname);
 
@@ -1044,15 +1042,7 @@ int purge_user(char pname[])
 	 * set the access level to 0, and let the account get swept up
 	 * during the next purge.
 	 */
-	user_is_logged_in = 0;
-	begin_critical_section(S_SESSION_TABLE);
-	for (ccptr = ContextList; ccptr != NULL; ccptr = ccptr->next) {
-		if (ccptr->user.usernum == usbuf.usernum) {
-			user_is_logged_in = 1;
-		}
-	}
-	end_critical_section(S_SESSION_TABLE);
-	if (user_is_logged_in == 1) {
+	if (CtdlIsUserLoggedInByNum(usbuf.usernum)) {
 		CtdlLogPrintf(CTDL_WARNING, "User <%s> is logged in; not deleting.\n", pname);
 		usbuf.axlevel = 0;
 		CtdlPutUser(&usbuf);
@@ -1060,6 +1050,16 @@ int purge_user(char pname[])
 	}
 	CtdlLogPrintf(CTDL_NOTICE, "Deleting user <%s>\n", pname);
 
+/*
+ * FIXME:
+ * This should all be wrapped in a S_USERS mutex.
+ * Without the mutex the user could log in before we get to the next function
+ * That would truly mess things up :-(
+ * I would like to see the S_USERS start before the CtdlIsUserLoggedInByNum() above
+ * and end after the user has been deleted from the database, below.
+ * Question is should we enter the EVT_PURGEUSER whilst S_USERS is active?
+ */
+
 	/* Perform any purge functions registered by server extensions */
 	PerformUserHooks(&usbuf, EVT_PURGEUSER);
 
-- 
2.30.2