#include "httpd.h"
#include "http_main.h"
-#ifdef AP_NEED_SET_MUTEX_PERMS
-#include "unixd.h"
-#endif
-
-#if APR_HAVE_UNISTD_H
-#include <unistd.h> /* for getpid() */
-#endif
-
-#if HAVE_SYS_SEM_H
-#include <sys/shm.h>
-#if !defined(SHM_R)
-#define SHM_R 0400
-#endif
-#if !defined(SHM_W)
-#define SHM_W 0200
-#endif
-#endif
#define AP_SLOTMEM_IS_PREGRAB(t) (t->desc.type & AP_SLOTMEM_TYPE_PREGRAB)
#define AP_SLOTMEM_IS_PERSIST(t) (t->desc.type & AP_SLOTMEM_TYPE_PERSIST)
struct ap_slotmem_instance_t {
char *name; /* per segment name */
+ char *pname; /* persisted file name */
int fbased; /* filebased? */
void *shm; /* ptr to memory segment (apr_shm_t *) */
void *base; /* data set start */
#define DEFAULT_SLOTMEM_SUFFIX ".shm"
#define DEFAULT_SLOTMEM_PERSIST_SUFFIX ".persist"
+/* Unixes (and Netware) have the unlink() semantic, which allows to
+ * apr_file_remove() a file still in use (opened elsewhere), the inode
+ * remains until the last fd is closed, whereas any file created with
+ * the same name/path will use a new inode.
+ *
+ * On windows and OS/2 ("\SHAREMEM\..." tree), apr_file_remove() marks
+ * the files for deletion until the last HANDLE is closed, meanwhile the
+ * same file/path can't be opened/recreated.
+ * Thus on graceful restart (the only restart mode with mpm_winnt), the
+ * old file may still exist until all the children stop, while we ought
+ * to create a new one for our new clear SHM. Therefore, we would only
+ * be able to reuse (attach) the old SHM, preventing some changes to
+ * the config file, like the number of balancers/members, since the
+ * size checks (to fit the new config) would fail. Let's avoid this by
+ * including the generation number in the SHM filename (obviously not
+ * the persisted name!)
+ */
+#ifndef SLOTMEM_UNLINK_SEMANTIC
+#if defined(WIN32) || defined(OS2)
+#define SLOTMEM_UNLINK_SEMANTIC 0
+#else
+#define SLOTMEM_UNLINK_SEMANTIC 1
+#endif
+#endif
+
/*
* Persist the slotmem in a file
* slotmem name and file name.
* /abs_name : $abs_name
*
*/
-
-static const char *slotmem_filename(apr_pool_t *pool, const char *slotmemname,
- int persist)
+static int slotmem_filenames(apr_pool_t *pool,
+ const char *slotname,
+ const char **filename,
+ const char **persistname)
{
- const char *fname;
- if (!slotmemname || strcasecmp(slotmemname, "none") == 0) {
- return NULL;
- }
- else if (slotmemname[0] != '/') {
- const char *filenm = apr_pstrcat(pool, DEFAULT_SLOTMEM_PREFIX,
- slotmemname, DEFAULT_SLOTMEM_SUFFIX,
- NULL);
- fname = ap_runtime_dir_relative(pool, filenm);
- }
- else {
- fname = slotmemname;
+ const char *fname = NULL, *pname = NULL;
+
+ if (slotname && *slotname && strcasecmp(slotname, "none") != 0) {
+ fname = slotname;
+#if SLOTMEM_UNLINK_SEMANTIC
+ /* Reuse the same file name for each generation. */
+ fname = apr_pstrcat(pool, DEFAULT_SLOTMEM_PREFIX,
+ fname, DEFAULT_SLOTMEM_SUFFIX,
+ NULL);
+#else
+ /* Each generation needs its own file name. */
+ fname = apr_psprintf(pool, "%s%s_%x%s", DEFAULT_SLOTMEM_PREFIX,
+ fname, ap_state_query(AP_SQ_CONFIG_GEN),
+ DEFAULT_SLOTMEM_SUFFIX);
+#endif
+ fname = ap_runtime_dir_relative(pool, fname);
+
+ if (persistname) {
+ /* Persisted file names are immutable... */
+#if SLOTMEM_UNLINK_SEMANTIC
+ pname = apr_pstrcat(pool, fname,
+ DEFAULT_SLOTMEM_PERSIST_SUFFIX,
+ NULL);
+#else
+ pname = apr_pstrcat(pool, DEFAULT_SLOTMEM_PREFIX,
+ slotname, DEFAULT_SLOTMEM_SUFFIX,
+ DEFAULT_SLOTMEM_PERSIST_SUFFIX,
+ NULL);
+ pname = ap_runtime_dir_relative(pool, pname);
+#endif
+ }
}
- if (persist) {
- return apr_pstrcat(pool, fname, DEFAULT_SLOTMEM_PERSIST_SUFFIX,
- NULL);
+ *filename = fname;
+ if (persistname) {
+ *persistname = pname;
}
- return fname;
+ return (fname != NULL);
}
static void slotmem_clearinuse(ap_slotmem_instance_t *slot)
apr_file_t *fp;
apr_status_t rv;
apr_size_t nbytes;
- const char *storename;
unsigned char digest[APR_MD5_DIGESTSIZE];
-
- storename = slotmem_filename(slotmem->gpool, slotmem->name, 1);
+ const char *storename = slotmem->pname;
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, ap_server_conf, APLOGNO(02334)
"storing %s", storename);
}
}
-static apr_status_t restore_slotmem(void *ptr, const char *name, apr_size_t size,
- apr_pool_t *pool)
+static apr_status_t restore_slotmem(void *ptr, const char *storename,
+ apr_size_t size, apr_pool_t *pool)
{
- const char *storename;
apr_file_t *fp;
apr_size_t nbytes = size;
apr_status_t rv = APR_SUCCESS;
unsigned char digest[APR_MD5_DIGESTSIZE];
unsigned char digest2[APR_MD5_DIGESTSIZE];
- storename = slotmem_filename(pool, name, 1);
-
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, ap_server_conf, APLOGNO(02335)
"restoring %s", storename);
store_slotmem(next);
}
if (next->fbased) {
- const char *name;
apr_shm_remove(next->name, next->gpool);
- name = slotmem_filename(next->gpool, next->name, 0);
- if (name) {
- apr_file_remove(name, next->gpool);
- }
+ apr_file_remove(next->name, next->gpool);
}
apr_shm_destroy((apr_shm_t *)next->shm);
next = next->next;
unsigned int item_num,
ap_slotmem_type_t type, apr_pool_t *pool)
{
-/* void *slotmem = NULL; */
int fbased = 1;
int restored = 0;
char *ptr;
sharedslotdesc_t desc;
ap_slotmem_instance_t *res;
ap_slotmem_instance_t *next = globallistmem;
- const char *fname;
+ const char *fname, *pname = NULL;
apr_shm_t *shm;
apr_size_t basesize = (item_size * item_num);
apr_size_t size = AP_SLOTMEM_OFFSET + AP_UNSIGNEDINT_OFFSET +
(item_num * sizeof(char)) + basesize;
+ int persist = (type & AP_SLOTMEM_TYPE_PERSIST) != 0;
apr_status_t rv;
if (gpool == NULL) {
return APR_ENOSHMAVAIL;
}
- fname = slotmem_filename(pool, name, 0);
- if (fname) {
+ if (slotmem_filenames(pool, name, &fname, persist ? &pname : NULL)) {
/* first try to attach to existing slotmem */
if (next) {
for (;;) {
* TODO: Error check the below... What error makes
* sense if the restore fails? Any?
*/
- if (type & AP_SLOTMEM_TYPE_PERSIST) {
- rv = restore_slotmem(ptr, fname, dsize, pool);
+ if (persist) {
+ rv = restore_slotmem(ptr, pname, dsize, pool);
if (rv == APR_SUCCESS) {
restored = 1;
}
res = (ap_slotmem_instance_t *) apr_pcalloc(gpool,
sizeof(ap_slotmem_instance_t));
res->name = apr_pstrdup(gpool, fname);
+ res->pname = apr_pstrdup(gpool, pname);
res->fbased = fbased;
res->shm = shm;
res->num_free = (unsigned int *)ptr;
if (gpool == NULL) {
return APR_ENOSHMAVAIL;
}
- fname = slotmem_filename(pool, name, 0);
- if (!fname) {
+ if (!slotmem_filenames(pool, name, &fname, NULL)) {
return APR_ENOSHMAVAIL;
}
projects / apache / commitdiff