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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 15:01:30 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 15:01:30 +0000
commit6beeb1b708550be0d4a53b272283e17e5e35fe17 (patch)
tree1ce8673d4aaa948e5554000101f46536a1e4cc29 /modules/cluster/mod_heartmonitor.c
parentInitial commit. (diff)
downloadapache2-6beeb1b708550be0d4a53b272283e17e5e35fe17.tar.xz
apache2-6beeb1b708550be0d4a53b272283e17e5e35fe17.zip
Adding upstream version 2.4.57.upstream/2.4.57upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'modules/cluster/mod_heartmonitor.c')
-rw-r--r--modules/cluster/mod_heartmonitor.c920
1 files changed, 920 insertions, 0 deletions
diff --git a/modules/cluster/mod_heartmonitor.c b/modules/cluster/mod_heartmonitor.c
new file mode 100644
index 0000000..53b6504
--- /dev/null
+++ b/modules/cluster/mod_heartmonitor.c
@@ -0,0 +1,920 @@
+/* Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "httpd.h"
+#include "http_config.h"
+#include "http_log.h"
+#include "http_core.h"
+#include "http_protocol.h"
+#include "apr_strings.h"
+#include "apr_hash.h"
+#include "apr_time.h"
+#include "ap_mpm.h"
+#include "scoreboard.h"
+#include "mod_watchdog.h"
+#include "ap_slotmem.h"
+#include "heartbeat.h"
+
+
+#ifndef HM_UPDATE_SEC
+/* How often we update the stats file */
+/* TODO: Make a runtime config */
+#define HM_UPDATE_SEC (5)
+#endif
+
+#define HM_WATHCHDOG_NAME ("_heartmonitor_")
+
+static const ap_slotmem_provider_t *storage = NULL;
+static ap_slotmem_instance_t *slotmem = NULL;
+static int maxworkers = 10;
+
+module AP_MODULE_DECLARE_DATA heartmonitor_module;
+
+typedef struct hm_server_t
+{
+ const char *ip;
+ int busy;
+ int ready;
+ unsigned int port;
+ apr_time_t seen;
+} hm_server_t;
+
+typedef struct hm_ctx_t
+{
+ int active;
+ const char *storage_path;
+ ap_watchdog_t *watchdog;
+ apr_interval_time_t interval;
+ apr_sockaddr_t *mcast_addr;
+ apr_status_t status;
+ volatile int keep_running;
+ apr_socket_t *sock;
+ apr_pool_t *p;
+ apr_hash_t *servers;
+ server_rec *s;
+} hm_ctx_t;
+
+typedef struct hm_slot_server_ctx_t {
+ hm_server_t *s;
+ int found;
+ unsigned int item_id;
+} hm_slot_server_ctx_t;
+
+static apr_status_t hm_listen(hm_ctx_t *ctx)
+{
+ apr_status_t rv;
+
+ rv = apr_socket_create(&ctx->sock, ctx->mcast_addr->family,
+ SOCK_DGRAM, APR_PROTO_UDP, ctx->p);
+
+ if (rv) {
+ ap_log_error(APLOG_MARK, APLOG_CRIT, rv, ctx->s, APLOGNO(02068)
+ "Failed to create listening socket.");
+ return rv;
+ }
+
+ rv = apr_socket_opt_set(ctx->sock, APR_SO_REUSEADDR, 1);
+ if (rv) {
+ ap_log_error(APLOG_MARK, APLOG_CRIT, rv, ctx->s, APLOGNO(02069)
+ "Failed to set APR_SO_REUSEADDR to 1 on socket.");
+ return rv;
+ }
+
+
+ rv = apr_socket_opt_set(ctx->sock, APR_SO_NONBLOCK, 1);
+ if (rv) {
+ ap_log_error(APLOG_MARK, APLOG_CRIT, rv, ctx->s, APLOGNO(02070)
+ "Failed to set APR_SO_NONBLOCK to 1 on socket.");
+ return rv;
+ }
+
+ rv = apr_socket_bind(ctx->sock, ctx->mcast_addr);
+ if (rv) {
+ ap_log_error(APLOG_MARK, APLOG_CRIT, rv, ctx->s, APLOGNO(02071)
+ "Failed to bind on socket.");
+ return rv;
+ }
+
+ rv = apr_mcast_join(ctx->sock, ctx->mcast_addr, NULL, NULL);
+
+ if (rv) {
+ ap_log_error(APLOG_MARK, APLOG_CRIT, rv, ctx->s, APLOGNO(02072)
+ "Failed to join multicast group");
+ return rv;
+ }
+
+ rv = apr_mcast_loopback(ctx->sock, 1);
+ if (rv) {
+ ap_log_error(APLOG_MARK, APLOG_CRIT, rv, ctx->s, APLOGNO(02073)
+ "Failed to accept localhost mulitcast on socket.");
+ return rv;
+ }
+
+ return APR_SUCCESS;
+}
+
+/* XXX: The same exists in mod_lbmethod_heartbeat.c where it is named argstr_to_table */
+static void qs_to_table(const char *input, apr_table_t *parms,
+ apr_pool_t *p)
+{
+ char *key;
+ char *value;
+ char *query_string;
+ char *strtok_state;
+
+ if (input == NULL) {
+ return;
+ }
+
+ query_string = apr_pstrdup(p, input);
+
+ key = apr_strtok(query_string, "&", &strtok_state);
+ while (key) {
+ value = strchr(key, '=');
+ if (value) {
+ *value = '\0'; /* Split the string in two */
+ value++; /* Skip passed the = */
+ }
+ else {
+ value = "1";
+ }
+ ap_unescape_url(key);
+ ap_unescape_url(value);
+ apr_table_set(parms, key, value);
+ /*
+ ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO(03182)
+ "Found query arg: %s = %s", key, value);
+ */
+ key = apr_strtok(NULL, "&", &strtok_state);
+ }
+}
+
+
+#define SEEN_TIMEOUT (30)
+
+/* Store in the slotmem */
+static apr_status_t hm_update(void* mem, void *data, apr_pool_t *p)
+{
+ hm_slot_server_t *old = (hm_slot_server_t *) mem;
+ hm_slot_server_ctx_t *s = (hm_slot_server_ctx_t *) data;
+ hm_server_t *new = s->s;
+ if (strcmp(old->ip, new->ip)==0) {
+ s->found = 1;
+ old->busy = new->busy;
+ old->ready = new->ready;
+ old->seen = new->seen;
+ }
+ return APR_SUCCESS;
+}
+/* Read the id corresponding to the entry in the slotmem */
+static apr_status_t hm_readid(void* mem, void *data, apr_pool_t *p)
+{
+ hm_slot_server_t *old = (hm_slot_server_t *) mem;
+ hm_slot_server_ctx_t *s = (hm_slot_server_ctx_t *) data;
+ hm_server_t *new = s->s;
+ if (strcmp(old->ip, new->ip)==0) {
+ s->found = 1;
+ s->item_id = old->id;
+ }
+ return APR_SUCCESS;
+}
+/* update the entry or create it if not existing */
+static apr_status_t hm_slotmem_update_stat(hm_server_t *s, apr_pool_t *pool)
+{
+ /* We call do_all (to try to update) otherwise grab + put */
+ hm_slot_server_ctx_t ctx;
+ ctx.s = s;
+ ctx.found = 0;
+ storage->doall(slotmem, hm_update, &ctx, pool);
+ if (!ctx.found) {
+ unsigned int i;
+ hm_slot_server_t hmserver;
+ memset(&hmserver, 0, sizeof(hmserver));
+ apr_cpystrn(hmserver.ip, s->ip, sizeof(hmserver.ip));
+ hmserver.busy = s->busy;
+ hmserver.ready = s->ready;
+ hmserver.seen = s->seen;
+ /* XXX locking for grab() / put() */
+ storage->grab(slotmem, &i);
+ hmserver.id = i;
+ storage->put(slotmem, i, (unsigned char *)&hmserver, sizeof(hmserver));
+ }
+ return APR_SUCCESS;
+}
+static apr_status_t hm_slotmem_remove_stat(hm_server_t *s, apr_pool_t *pool)
+{
+ hm_slot_server_ctx_t ctx;
+ ctx.s = s;
+ ctx.found = 0;
+ storage->doall(slotmem, hm_readid, &ctx, pool);
+ if (ctx.found) {
+ storage->release(slotmem, ctx.item_id);
+ }
+ return APR_SUCCESS;
+}
+static apr_status_t hm_file_update_stat(hm_ctx_t *ctx, hm_server_t *s, apr_pool_t *pool)
+{
+ apr_status_t rv;
+ apr_file_t *fp;
+ apr_file_t *fpin;
+ apr_time_t now;
+ apr_time_t fage;
+ apr_finfo_t fi;
+ int updated = 0;
+ char *path = apr_pstrcat(pool, ctx->storage_path, ".tmp.XXXXXX", NULL);
+
+
+ /* TODO: Update stats file (!) */
+ rv = apr_file_mktemp(&fp, path, APR_CREATE | APR_WRITE, pool);
+
+ if (rv) {
+ ap_log_error(APLOG_MARK, APLOG_CRIT, rv, ctx->s, APLOGNO(02074)
+ "Unable to open tmp file: %s", path);
+ return rv;
+ }
+ rv = apr_file_open(&fpin, ctx->storage_path, APR_READ|APR_BINARY|APR_BUFFERED,
+ APR_OS_DEFAULT, pool);
+
+ now = apr_time_now();
+ if (rv == APR_SUCCESS) {
+ char *t;
+ apr_table_t *hbt = apr_table_make(pool, 10);
+ apr_bucket_alloc_t *ba;
+ apr_bucket_brigade *bb;
+ apr_bucket_brigade *tmpbb;
+
+ rv = apr_file_info_get(&fi, APR_FINFO_SIZE | APR_FINFO_MTIME, fpin);
+ if (rv) {
+ ap_log_error(APLOG_MARK, APLOG_CRIT, rv, ctx->s, APLOGNO(02075)
+ "Unable to read file: %s", ctx->storage_path);
+ return rv;
+ }
+
+ /* Read the file and update the line corresponding to the node */
+ ba = apr_bucket_alloc_create(pool);
+ bb = apr_brigade_create(pool, ba);
+ apr_brigade_insert_file(bb, fpin, 0, fi.size, pool);
+ tmpbb = apr_brigade_create(pool, ba);
+ fage = apr_time_sec(now - fi.mtime);
+ do {
+ char buf[4096];
+ const char *ip;
+ apr_size_t bsize = sizeof(buf);
+
+ apr_brigade_cleanup(tmpbb);
+ if (APR_BRIGADE_EMPTY(bb)) {
+ break;
+ }
+ rv = apr_brigade_split_line(tmpbb, bb,
+ APR_BLOCK_READ, sizeof(buf));
+
+ if (rv) {
+ ap_log_error(APLOG_MARK, APLOG_CRIT, rv, ctx->s, APLOGNO(02076)
+ "Unable to read from file: %s", ctx->storage_path);
+ return rv;
+ }
+
+ apr_brigade_flatten(tmpbb, buf, &bsize);
+ if (bsize == 0) {
+ break;
+ }
+ buf[bsize - 1] = 0;
+ t = strchr(buf, ' ');
+ if (t) {
+ ip = apr_pstrmemdup(pool, buf, t - buf);
+ }
+ else {
+ ip = NULL;
+ }
+
+ if (!ip || buf[0] == '#') {
+ /* copy things we can't process */
+ apr_file_printf(fp, "%s\n", buf);
+ }
+ else if (strcmp(ip, s->ip) != 0 ) {
+ hm_server_t node;
+ apr_time_t seen;
+ const char *val;
+
+ /* Update seen time according to the last file modification */
+ apr_table_clear(hbt);
+ qs_to_table(apr_pstrdup(pool, t), hbt, pool);
+ if ((val = apr_table_get(hbt, "busy"))) {
+ node.busy = atoi(val);
+ }
+ else {
+ node.busy = 0;
+ }
+
+ if ((val = apr_table_get(hbt, "ready"))) {
+ node.ready = atoi(val);
+ }
+ else {
+ node.ready = 0;
+ }
+
+ if ((val = apr_table_get(hbt, "lastseen"))) {
+ node.seen = atoi(val);
+ }
+ else {
+ node.seen = SEEN_TIMEOUT;
+ }
+ seen = fage + node.seen;
+
+ if ((val = apr_table_get(hbt, "port"))) {
+ node.port = atoi(val);
+ }
+ else {
+ node.port = 80;
+ }
+ apr_file_printf(fp, "%s &ready=%u&busy=%u&lastseen=%u&port=%u\n",
+ ip, node.ready, node.busy, (unsigned int) seen, node.port);
+ }
+ else {
+ apr_time_t seen;
+ seen = apr_time_sec(now - s->seen);
+ apr_file_printf(fp, "%s &ready=%u&busy=%u&lastseen=%u&port=%u\n",
+ s->ip, s->ready, s->busy, (unsigned int) seen, s->port);
+ updated = 1;
+ }
+ } while (1);
+ }
+
+ if (!updated) {
+ apr_time_t seen;
+ seen = apr_time_sec(now - s->seen);
+ apr_file_printf(fp, "%s &ready=%u&busy=%u&lastseen=%u&port=%u\n",
+ s->ip, s->ready, s->busy, (unsigned int) seen, s->port);
+ }
+
+ rv = apr_file_flush(fp);
+ if (rv) {
+ ap_log_error(APLOG_MARK, APLOG_CRIT, rv, ctx->s, APLOGNO(02077)
+ "Unable to flush file: %s", path);
+ return rv;
+ }
+
+ rv = apr_file_close(fp);
+ if (rv) {
+ ap_log_error(APLOG_MARK, APLOG_CRIT, rv, ctx->s, APLOGNO(02078)
+ "Unable to close file: %s", path);
+ return rv;
+ }
+
+ rv = apr_file_perms_set(path,
+ APR_FPROT_UREAD | APR_FPROT_GREAD |
+ APR_FPROT_WREAD);
+ if (rv && rv != APR_INCOMPLETE && rv != APR_ENOTIMPL) {
+ ap_log_error(APLOG_MARK, APLOG_CRIT, rv, ctx->s, APLOGNO(02079)
+ "Unable to set file permissions on %s",
+ path);
+ return rv;
+ }
+
+ rv = apr_file_rename(path, ctx->storage_path, pool);
+
+ if (rv) {
+ ap_log_error(APLOG_MARK, APLOG_CRIT, rv, ctx->s, APLOGNO(02080)
+ "Unable to move file: %s -> %s", path,
+ ctx->storage_path);
+ return rv;
+ }
+
+ return APR_SUCCESS;
+}
+static apr_status_t hm_update_stat(hm_ctx_t *ctx, hm_server_t *s, apr_pool_t *pool)
+{
+ if (slotmem)
+ return hm_slotmem_update_stat(s, pool);
+ else
+ return hm_file_update_stat(ctx, s, pool);
+}
+
+/* Store in a file */
+static apr_status_t hm_file_update_stats(hm_ctx_t *ctx, apr_pool_t *p)
+{
+ apr_status_t rv;
+ apr_file_t *fp;
+ apr_hash_index_t *hi;
+ apr_time_t now;
+ char *path = apr_pstrcat(p, ctx->storage_path, ".tmp.XXXXXX", NULL);
+ /* TODO: Update stats file (!) */
+ rv = apr_file_mktemp(&fp, path, APR_CREATE | APR_WRITE, p);
+
+ if (rv) {
+ ap_log_error(APLOG_MARK, APLOG_CRIT, rv, ctx->s, APLOGNO(02081)
+ "Unable to open tmp file: %s", path);
+ return rv;
+ }
+
+ now = apr_time_now();
+ for (hi = apr_hash_first(p, ctx->servers);
+ hi != NULL; hi = apr_hash_next(hi)) {
+ hm_server_t *s = NULL;
+ apr_time_t seen;
+ apr_hash_this(hi, NULL, NULL, (void **) &s);
+ seen = apr_time_sec(now - s->seen);
+ if (seen > SEEN_TIMEOUT) {
+ /*
+ * Skip this entry from the heartbeat file -- when it comes back,
+ * we will reuse the memory...
+ */
+ }
+ else {
+ apr_file_printf(fp, "%s &ready=%u&busy=%u&lastseen=%u&port=%u\n",
+ s->ip, s->ready, s->busy, (unsigned int) seen, s->port);
+ }
+ }
+
+ rv = apr_file_flush(fp);
+ if (rv) {
+ ap_log_error(APLOG_MARK, APLOG_CRIT, rv, ctx->s, APLOGNO(02082)
+ "Unable to flush file: %s", path);
+ return rv;
+ }
+
+ rv = apr_file_close(fp);
+ if (rv) {
+ ap_log_error(APLOG_MARK, APLOG_CRIT, rv, ctx->s, APLOGNO(02083)
+ "Unable to close file: %s", path);
+ return rv;
+ }
+
+ rv = apr_file_perms_set(path,
+ APR_FPROT_UREAD | APR_FPROT_GREAD |
+ APR_FPROT_WREAD);
+ if (rv && rv != APR_INCOMPLETE && rv != APR_ENOTIMPL) {
+ ap_log_error(APLOG_MARK, APLOG_CRIT, rv, ctx->s, APLOGNO(02084)
+ "Unable to set file permissions on %s",
+ path);
+ return rv;
+ }
+
+ rv = apr_file_rename(path, ctx->storage_path, p);
+
+ if (rv) {
+ ap_log_error(APLOG_MARK, APLOG_CRIT, rv, ctx->s, APLOGNO(02085)
+ "Unable to move file: %s -> %s", path,
+ ctx->storage_path);
+ return rv;
+ }
+
+ return APR_SUCCESS;
+}
+/* Store in a slotmem */
+static apr_status_t hm_slotmem_update_stats(hm_ctx_t *ctx, apr_pool_t *p)
+{
+ apr_status_t rv;
+ apr_time_t now;
+ apr_hash_index_t *hi;
+ now = apr_time_now();
+ for (hi = apr_hash_first(p, ctx->servers);
+ hi != NULL; hi = apr_hash_next(hi)) {
+ hm_server_t *s = NULL;
+ apr_time_t seen;
+ apr_hash_this(hi, NULL, NULL, (void **) &s);
+ seen = apr_time_sec(now - s->seen);
+ if (seen > SEEN_TIMEOUT) {
+ /* remove it */
+ rv = hm_slotmem_remove_stat(s, p);
+ } else {
+ /* update it */
+ rv = hm_slotmem_update_stat(s, p);
+ }
+ if (rv !=APR_SUCCESS)
+ return rv;
+ }
+ return APR_SUCCESS;
+}
+/* Store/update the stats */
+static apr_status_t hm_update_stats(hm_ctx_t *ctx, apr_pool_t *p)
+{
+ if (slotmem)
+ return hm_slotmem_update_stats(ctx, p);
+ else
+ return hm_file_update_stats(ctx, p);
+}
+
+static hm_server_t *hm_get_server(hm_ctx_t *ctx, const char *ip, const int port)
+{
+ hm_server_t *s;
+
+ s = apr_hash_get(ctx->servers, ip, APR_HASH_KEY_STRING);
+
+ if (s == NULL) {
+ s = apr_palloc(ctx->p, sizeof(hm_server_t));
+ s->ip = apr_pstrdup(ctx->p, ip);
+ s->port = port;
+ s->ready = 0;
+ s->busy = 0;
+ s->seen = 0;
+ apr_hash_set(ctx->servers, s->ip, APR_HASH_KEY_STRING, s);
+ }
+
+ return s;
+}
+
+/* Process a message received from a backend node */
+static void hm_processmsg(hm_ctx_t *ctx, apr_pool_t *p,
+ apr_sockaddr_t *from, char *buf, apr_size_t len)
+{
+ apr_table_t *tbl;
+
+ buf[len] = '\0';
+
+ tbl = apr_table_make(p, 10);
+
+ qs_to_table(buf, tbl, p);
+
+ if (apr_table_get(tbl, "v") != NULL &&
+ apr_table_get(tbl, "busy") != NULL &&
+ apr_table_get(tbl, "ready") != NULL) {
+ char *ip;
+ int port = 80;
+ hm_server_t *s;
+ /* TODO: REMOVE ME BEFORE PRODUCTION (????) */
+ ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, ctx->s, APLOGNO(02086)
+ "%pI busy=%s ready=%s", from,
+ apr_table_get(tbl, "busy"), apr_table_get(tbl, "ready"));
+
+ apr_sockaddr_ip_get(&ip, from);
+
+ if (apr_table_get(tbl, "port") != NULL)
+ port = atoi(apr_table_get(tbl, "port"));
+
+ s = hm_get_server(ctx, ip, port);
+
+ s->busy = atoi(apr_table_get(tbl, "busy"));
+ s->ready = atoi(apr_table_get(tbl, "ready"));
+ s->seen = apr_time_now();
+ }
+ else {
+ ap_log_error(APLOG_MARK, APLOG_CRIT, 0, ctx->s, APLOGNO(02087)
+ "malformed message from %pI",
+ from);
+ }
+
+}
+/* Read message from multicast socket */
+#define MAX_MSG_LEN (1000)
+static apr_status_t hm_recv(hm_ctx_t *ctx, apr_pool_t *p)
+{
+ char buf[MAX_MSG_LEN + 1];
+ apr_sockaddr_t from;
+ apr_size_t len = MAX_MSG_LEN;
+ apr_status_t rv;
+
+ from.pool = p;
+
+ rv = apr_socket_recvfrom(&from, ctx->sock, 0, buf, &len);
+
+ if (APR_STATUS_IS_EAGAIN(rv)) {
+ ap_log_error(APLOG_MARK, APLOG_CRIT, rv, ctx->s, APLOGNO(02088) "would block");
+ return APR_SUCCESS;
+ }
+ else if (rv) {
+ ap_log_error(APLOG_MARK, APLOG_CRIT, rv, ctx->s, APLOGNO(02089) "recvfrom failed");
+ return rv;
+ }
+
+ hm_processmsg(ctx, p, &from, buf, len);
+
+ return rv;
+}
+
+static apr_status_t hm_watchdog_callback(int state, void *data,
+ apr_pool_t *pool)
+{
+ apr_status_t rv = APR_SUCCESS;
+ apr_time_t cur, now;
+ hm_ctx_t *ctx = (hm_ctx_t *)data;
+
+ if (!ctx->active) {
+ return rv;
+ }
+
+ switch (state) {
+ case AP_WATCHDOG_STATE_STARTING:
+ rv = hm_listen(ctx);
+ if (rv) {
+ ctx->status = rv;
+ ap_log_error(APLOG_MARK, APLOG_CRIT, rv, ctx->s, APLOGNO(02090)
+ "Unable to listen for connections!");
+ }
+ else {
+ ctx->keep_running = 1;
+ ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, ctx->s, APLOGNO(02091)
+ "%s listener started.",
+ HM_WATHCHDOG_NAME);
+ }
+ break;
+ case AP_WATCHDOG_STATE_RUNNING:
+ /* store in the slotmem or in the file depending on configuration */
+ hm_update_stats(ctx, pool);
+ cur = now = apr_time_sec(apr_time_now());
+
+ while ((now - cur) < apr_time_sec(ctx->interval)) {
+ int n;
+ apr_status_t rc;
+ apr_pool_t *p;
+ apr_pollfd_t pfd;
+ apr_interval_time_t timeout;
+
+ apr_pool_create(&p, pool);
+ apr_pool_tag(p, "hm_running");
+
+ pfd.desc_type = APR_POLL_SOCKET;
+ pfd.desc.s = ctx->sock;
+ pfd.p = p;
+ pfd.reqevents = APR_POLLIN;
+
+ timeout = apr_time_from_sec(1);
+
+ rc = apr_poll(&pfd, 1, &n, timeout);
+
+ if (!ctx->keep_running) {
+ apr_pool_destroy(p);
+ break;
+ }
+ if (rc == APR_SUCCESS && (pfd.rtnevents & APR_POLLIN)) {
+ hm_recv(ctx, p);
+ }
+ now = apr_time_sec(apr_time_now());
+ apr_pool_destroy(p);
+ }
+ break;
+ case AP_WATCHDOG_STATE_STOPPING:
+ ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, ctx->s, APLOGNO(02092)
+ "stopping %s listener.",
+ HM_WATHCHDOG_NAME);
+
+ ctx->keep_running = 0;
+ if (ctx->sock) {
+ apr_socket_close(ctx->sock);
+ ctx->sock = NULL;
+ }
+ break;
+ }
+ return rv;
+}
+
+static int hm_post_config(apr_pool_t *p, apr_pool_t *plog,
+ apr_pool_t *ptemp, server_rec *s)
+{
+ apr_status_t rv;
+ hm_ctx_t *ctx = ap_get_module_config(s->module_config,
+ &heartmonitor_module);
+ APR_OPTIONAL_FN_TYPE(ap_watchdog_get_instance) *hm_watchdog_get_instance;
+ APR_OPTIONAL_FN_TYPE(ap_watchdog_register_callback) *hm_watchdog_register_callback;
+
+ hm_watchdog_get_instance = APR_RETRIEVE_OPTIONAL_FN(ap_watchdog_get_instance);
+ hm_watchdog_register_callback = APR_RETRIEVE_OPTIONAL_FN(ap_watchdog_register_callback);
+ if (!hm_watchdog_get_instance || !hm_watchdog_register_callback) {
+ ap_log_error(APLOG_MARK, APLOG_CRIT, 0, s, APLOGNO(02093)
+ "mod_watchdog is required");
+ return !OK;
+ }
+
+ /* Create the slotmem */
+ if (ap_state_query(AP_SQ_MAIN_STATE) == AP_SQ_MS_CREATE_CONFIG) {
+ /* this is the real thing */
+ if (maxworkers) {
+ storage = ap_lookup_provider(AP_SLOTMEM_PROVIDER_GROUP, "shm",
+ AP_SLOTMEM_PROVIDER_VERSION);
+ if (!storage) {
+ ap_log_error(APLOG_MARK, APLOG_EMERG, 0, s, APLOGNO(02284)
+ "failed to lookup provider 'shm' for '%s', "
+ "maybe you need to load mod_slotmem_shm?",
+ AP_SLOTMEM_PROVIDER_GROUP);
+ return !OK;
+ }
+ storage->create(&slotmem, "mod_heartmonitor", sizeof(hm_slot_server_t), maxworkers, AP_SLOTMEM_TYPE_PREGRAB, p);
+ if (!slotmem) {
+ ap_log_error(APLOG_MARK, APLOG_EMERG, 0, s, APLOGNO(02285)
+ "slotmem_create for status failed");
+ return !OK;
+ }
+ }
+ }
+
+ if (!ctx->active) {
+ return OK;
+ }
+ rv = hm_watchdog_get_instance(&ctx->watchdog,
+ HM_WATHCHDOG_NAME,
+ 0, 1, p);
+ if (rv) {
+ ap_log_error(APLOG_MARK, APLOG_CRIT, rv, s, APLOGNO(02094)
+ "Failed to create watchdog instance (%s)",
+ HM_WATHCHDOG_NAME);
+ return !OK;
+ }
+ /* Register a callback with zero interval. */
+ rv = hm_watchdog_register_callback(ctx->watchdog,
+ 0,
+ ctx,
+ hm_watchdog_callback);
+ if (rv) {
+ ap_log_error(APLOG_MARK, APLOG_CRIT, rv, s, APLOGNO(02095)
+ "Failed to register watchdog callback (%s)",
+ HM_WATHCHDOG_NAME);
+ return !OK;
+ }
+ ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s, APLOGNO(02096)
+ "wd callback %s", HM_WATHCHDOG_NAME);
+ return OK;
+}
+
+static int hm_handler(request_rec *r)
+{
+ apr_bucket_brigade *input_brigade;
+ apr_size_t len;
+ char *buf;
+ apr_status_t status;
+ apr_table_t *tbl;
+ hm_server_t hmserver;
+ char *ip;
+ hm_ctx_t *ctx;
+
+ if (strcmp(r->handler, "heartbeat")) {
+ return DECLINED;
+ }
+ if (r->method_number != M_POST) {
+ return HTTP_METHOD_NOT_ALLOWED;
+ }
+
+ len = MAX_MSG_LEN;
+ ctx = ap_get_module_config(r->server->module_config,
+ &heartmonitor_module);
+
+ buf = apr_pcalloc(r->pool, MAX_MSG_LEN);
+ input_brigade = apr_brigade_create(r->connection->pool, r->connection->bucket_alloc);
+ status = ap_get_brigade(r->input_filters, input_brigade, AP_MODE_READBYTES, APR_BLOCK_READ, MAX_MSG_LEN);
+ if (status != APR_SUCCESS) {
+ return ap_map_http_request_error(status, HTTP_BAD_REQUEST);
+ }
+ apr_brigade_flatten(input_brigade, buf, &len);
+
+ /* we can't use hm_processmsg because it uses hm_get_server() */
+ buf[len] = '\0';
+ tbl = apr_table_make(r->pool, 10);
+ qs_to_table(buf, tbl, r->pool);
+ apr_sockaddr_ip_get(&ip, r->connection->client_addr);
+ hmserver.ip = ip;
+ hmserver.port = 80;
+ if (apr_table_get(tbl, "port") != NULL)
+ hmserver.port = atoi(apr_table_get(tbl, "port"));
+ hmserver.busy = atoi(apr_table_get(tbl, "busy"));
+ hmserver.ready = atoi(apr_table_get(tbl, "ready"));
+ hmserver.seen = apr_time_now();
+ hm_update_stat(ctx, &hmserver, r->pool);
+
+ ap_set_content_type(r, "text/plain");
+ ap_set_content_length(r, 2);
+ ap_rputs("OK", r);
+ ap_rflush(r);
+
+ return OK;
+}
+
+static void hm_register_hooks(apr_pool_t *p)
+{
+ static const char * const aszSucc[]={ "mod_proxy.c", NULL };
+ ap_hook_post_config(hm_post_config, NULL, NULL, APR_HOOK_MIDDLE);
+
+ ap_hook_handler(hm_handler, NULL, aszSucc, APR_HOOK_FIRST);
+}
+
+static void *hm_create_config(apr_pool_t *p, server_rec *s)
+{
+ hm_ctx_t *ctx = (hm_ctx_t *) apr_palloc(p, sizeof(hm_ctx_t));
+
+ ctx->active = 0;
+ ctx->storage_path = ap_runtime_dir_relative(p, DEFAULT_HEARTBEAT_STORAGE);
+ /* TODO: Add directive for tuning the update interval
+ */
+ ctx->interval = apr_time_from_sec(HM_UPDATE_SEC);
+ ctx->s = s;
+ apr_pool_create(&ctx->p, p);
+ apr_pool_tag(ctx->p, "hm_ctx");
+ ctx->servers = apr_hash_make(ctx->p);
+
+ return ctx;
+}
+
+static const char *cmd_hm_storage(cmd_parms *cmd,
+ void *dconf, const char *path)
+{
+ apr_pool_t *p = cmd->pool;
+ hm_ctx_t *ctx =
+ (hm_ctx_t *) ap_get_module_config(cmd->server->module_config,
+ &heartmonitor_module);
+ const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
+
+ if (err != NULL) {
+ return err;
+ }
+
+ ctx->storage_path = ap_runtime_dir_relative(p, path);
+
+ return NULL;
+}
+
+static const char *cmd_hm_listen(cmd_parms *cmd,
+ void *dconf, const char *mcast_addr)
+{
+ apr_status_t rv;
+ char *host_str;
+ char *scope_id;
+ apr_port_t port = 0;
+ apr_pool_t *p = cmd->pool;
+ hm_ctx_t *ctx =
+ (hm_ctx_t *) ap_get_module_config(cmd->server->module_config,
+ &heartmonitor_module);
+ const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
+
+ if (err != NULL) {
+ return err;
+ }
+
+ if (!ctx->active) {
+ ctx->active = 1;
+ }
+ else {
+ return "HeartbeatListen: May only be specified once.";
+ }
+
+ rv = apr_parse_addr_port(&host_str, &scope_id, &port, mcast_addr, cmd->temp_pool);
+
+ if (rv) {
+ return "HeartbeatListen: Unable to parse multicast address.";
+ }
+
+ if (host_str == NULL) {
+ return "HeartbeatListen: No host provided in multicast address";
+ }
+
+ if (port == 0) {
+ return "HeartbeatListen: No port provided in multicast address";
+ }
+
+ rv = apr_sockaddr_info_get(&ctx->mcast_addr, host_str, APR_INET, port, 0,
+ p);
+
+ if (rv) {
+ return
+ "HeartbeatListen: apr_sockaddr_info_get failed on multicast address";
+ }
+
+ return NULL;
+}
+
+static const char *cmd_hm_maxworkers(cmd_parms *cmd,
+ void *dconf, const char *data)
+{
+ const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
+
+ if (err != NULL) {
+ return err;
+ }
+
+ maxworkers = atoi(data);
+ if (maxworkers != 0 && maxworkers < 10)
+ return "HeartbeatMaxServers: Should be 0 for file storage, "
+ "or greater or equal than 10 for slotmem";
+
+ return NULL;
+}
+
+static const command_rec hm_cmds[] = {
+ AP_INIT_TAKE1("HeartbeatListen", cmd_hm_listen, NULL, RSRC_CONF,
+ "Address to listen for heartbeat requests"),
+ AP_INIT_TAKE1("HeartbeatStorage", cmd_hm_storage, NULL, RSRC_CONF,
+ "Path to store heartbeat data."),
+ AP_INIT_TAKE1("HeartbeatMaxServers", cmd_hm_maxworkers, NULL, RSRC_CONF,
+ "Max number of servers when using slotmem (instead file) to store heartbeat data."),
+ {NULL}
+};
+
+AP_DECLARE_MODULE(heartmonitor) = {
+ STANDARD20_MODULE_STUFF,
+ NULL, /* create per-directory config structure */
+ NULL, /* merge per-directory config structures */
+ hm_create_config, /* create per-server config structure */
+ NULL, /* merge per-server config structures */
+ hm_cmds, /* command apr_table_t */
+ hm_register_hooks
+};