diff options
Diffstat (limited to 'framework/src/audit/audisp/plugins/zos-remote/zos-remote-queue.c')
| -rw-r--r-- | framework/src/audit/audisp/plugins/zos-remote/zos-remote-queue.c | 144 |
1 files changed, 144 insertions, 0 deletions
diff --git a/framework/src/audit/audisp/plugins/zos-remote/zos-remote-queue.c b/framework/src/audit/audisp/plugins/zos-remote/zos-remote-queue.c new file mode 100644 index 00000000..8071dca4 --- /dev/null +++ b/framework/src/audit/audisp/plugins/zos-remote/zos-remote-queue.c @@ -0,0 +1,144 @@ +/*************************************************************************** + * Copyright (C) 2007 International Business Machines Corp. * + * All Rights Reserved. * + * * + * This program is free software; you can redistribute it and/or modify * + * it under the terms of the GNU General Public License as published by * + * the Free Software Foundation; either version 2 of the License, or * + * (at your option) any later version. * + * * + * This program is distributed in the hope that it will be useful, * + * but WITHOUT ANY WARRANTY; without even the implied warranty of * + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * + * GNU General Public License for more details. * + * * + * You should have received a copy of the GNU General Public License * + * along with this program; if not, write to the * + * Free Software Foundation, Inc., * + * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. * + * * + * Authors: * + * Klaus Heinrich Kiwi <klausk@br.ibm.com> * + * based on code by Steve Grubb <sgrubb@redhat.com> * + ***************************************************************************/ + +#include "zos-remote-queue.h" + +#include <stdlib.h> +#include <pthread.h> +#include <syslog.h> +#include "zos-remote-log.h" + +static volatile BerElement **q; +static pthread_mutex_t queue_lock; +static pthread_cond_t queue_nonempty; +static unsigned int q_next, q_last, q_depth; + + +int init_queue(unsigned int size) +{ + unsigned int i; + + q_next = 0; + q_last = 0; + q_depth = size; + q = malloc(q_depth * sizeof(BerElement *)); + if (q == NULL) + return -1; + + for (i=0; i<q_depth; i++) + q[i] = NULL; + + /* Setup IPC mechanisms */ + pthread_mutex_init(&queue_lock, NULL); + pthread_cond_init(&queue_nonempty, NULL); + + return 0; +} + +void enqueue(BerElement *ber) +{ + unsigned int n, retry_cnt = 0; + +retry: + /* We allow 3 retries and then its over */ + if (retry_cnt > 3) { + log_err("queue is full - dropping event"); + return; + } + pthread_mutex_lock(&queue_lock); + + /* OK, have lock add event */ + n = q_next%q_depth; + if (q[n] == NULL) { + q[n] = ber; + q_next = (n+1) % q_depth; + pthread_cond_signal(&queue_nonempty); + pthread_mutex_unlock(&queue_lock); + } else { + pthread_mutex_unlock(&queue_lock); + pthread_yield(); /* Let dequeue thread run to clear queue */ + retry_cnt++; + goto retry; + } +} + +BerElement *dequeue(void) +{ + BerElement *ber; + unsigned int n; + + /* Wait until its got something in it */ + pthread_mutex_lock(&queue_lock); + n = q_last%q_depth; + if (q[n] == NULL) { + pthread_cond_wait(&queue_nonempty, &queue_lock); + n = q_last%q_depth; + } + + /* OK, grab the next event */ + if (q[n] != NULL) { + ber = (BerElement *) q[n]; + q[n] = NULL; + q_last = (n+1) % q_depth; + } else + ber = NULL; + + pthread_mutex_unlock(&queue_lock); + + /* Process the event */ + return ber; +} + +void nudge_queue(void) +{ + pthread_cond_signal(&queue_nonempty); +} + +void increase_queue_depth(unsigned int size) +{ + pthread_mutex_lock(&queue_lock); + if (size > q_depth) { + unsigned int i; + void *tmp_q; + + tmp_q = realloc(q, size * sizeof(BerElement *)); + q = tmp_q; + for (i=q_depth; i<size; i++) + q[i] = NULL; + q_depth = size; + } + pthread_mutex_unlock(&queue_lock); +} + +void destroy_queue(void) +{ + unsigned int i; + + for (i=0; i<q_depth; i++) { + ber_free(q[i], 1); + } + + free(q); +} + |