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Posted to cvs@httpd.apache.org by yl...@apache.org on 2018/02/06 23:30:41 UTC
svn commit: r1823412 - /httpd/httpd/trunk/modules/slotmem/mod_slotmem_shm.c
Author: ylavic
Date: Tue Feb 6 23:30:41 2018
New Revision: 1823412
URL: http://svn.apache.org/viewvc?rev=1823412&view=rev
Log:
mod_slotmem_shm: follow up tp r1822509.
Check SHM sizes when reused, reload may have changed the needs.
Modified:
httpd/httpd/trunk/modules/slotmem/mod_slotmem_shm.c
Modified: httpd/httpd/trunk/modules/slotmem/mod_slotmem_shm.c
URL: http://svn.apache.org/viewvc/httpd/httpd/trunk/modules/slotmem/mod_slotmem_shm.c?rev=1823412&r1=1823411&r2=1823412&view=diff
==============================================================================
--- httpd/httpd/trunk/modules/slotmem/mod_slotmem_shm.c (original)
+++ httpd/httpd/trunk/modules/slotmem/mod_slotmem_shm.c Tue Feb 6 23:30:41 2018
@@ -362,6 +362,32 @@ static apr_status_t slotmem_doall(ap_slo
return retval;
}
+static int check_slotmem(ap_slotmem_instance_t *mem, apr_size_t size,
+ apr_size_t item_size, unsigned int item_num)
+{
+ sharedslotdesc_t *desc;
+
+ /* check size */
+ if (apr_shm_size_get(mem->shm) != size) {
+ ap_log_error(APLOG_MARK, APLOG_ERR, 0, ap_server_conf, APLOGNO(02599)
+ "existing shared memory for %s could not be used "
+ "(failed size check)",
+ mem->name);
+ return 0;
+ }
+
+ desc = apr_shm_baseaddr_get(mem->shm);
+ if (desc->size != item_size || desc->num != item_num) {
+ ap_log_error(APLOG_MARK, APLOG_ERR, 0, ap_server_conf, APLOGNO(02600)
+ "existing shared memory for %s could not be used "
+ "(failed contents check)",
+ mem->name);
+ return 0;
+ }
+
+ return 1;
+}
+
static apr_status_t slotmem_create(ap_slotmem_instance_t **new,
const char *name, apr_size_t item_size,
unsigned int item_num,
@@ -382,13 +408,31 @@ static apr_status_t slotmem_create(ap_sl
apr_status_t rv;
apr_pool_t *p;
+ *new = NULL;
+
if (slotmem_filenames(pool, name, &fname, persist ? &pname : NULL)) {
/* first try to attach to existing slotmem */
if (next) {
+ ap_slotmem_instance_t *prev = NULL;
for (;;) {
if (strcmp(next->name, fname) == 0) {
+ *new = next; /* either returned here or reused finally */
+ if (!check_slotmem(next, size, item_size, item_num)) {
+ apr_shm_destroy(next->shm);
+ next = next->next;
+ if (prev) {
+ prev->next = next;
+ }
+ else {
+ globallistmem = next;
+ }
+ if (next) {
+ continue;
+ }
+ next = prev;
+ break;
+ }
/* we already have it */
- *new = next;
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, ap_server_conf, APLOGNO(02603)
"create found %s in global list", fname);
return APR_SUCCESS;
@@ -396,6 +440,7 @@ static apr_status_t slotmem_create(ap_sl
if (!next->next) {
break;
}
+ prev = next;
next = next->next;
}
}
@@ -412,7 +457,6 @@ static apr_status_t slotmem_create(ap_sl
"create %s: %"APR_SIZE_T_FMT"/%u", fname, item_size,
item_num);
-
{
if (fbased) {
apr_shm_remove(fname, pool);
@@ -460,10 +504,14 @@ static apr_status_t slotmem_create(ap_sl
p = fbased ? gpool : pool;
ptr = (char *)desc + AP_SLOTMEM_OFFSET;
- /* For the chained slotmem stuff */
- res = apr_pcalloc(p, sizeof(ap_slotmem_instance_t));
- res->name = apr_pstrdup(p, fname);
- res->pname = apr_pstrdup(p, pname);
+ /* For the chained slotmem stuff (*new may be reused from above) */
+ res = *new;
+ if (res == NULL) {
+ res = apr_pcalloc(p, sizeof(ap_slotmem_instance_t));
+ res->name = apr_pstrdup(p, fname);
+ res->pname = apr_pstrdup(p, pname);
+ *new = res;
+ }
res->fbased = fbased;
res->shm = shm;
res->persist = (void *)ptr;
@@ -486,7 +534,6 @@ static apr_status_t slotmem_create(ap_sl
}
}
- *new = res;
return APR_SUCCESS;
}