Implement shared memory cleanup handlers on Unix for both the original

creating process' pool (cleans up after apr_shm_create) and an attaching
process' pool (cleans up after apr_shm_attach).


git-svn-id: https://svn.apache.org/repos/asf/apr/apr/trunk@62848 13f79535-47bb-0310-9956-ffa450edef68

1 files changed, 98 insertions, 66 deletions

diff --git a/shmem/unix/shm.c b/shmem/unix/shm.c
index f965e9dae..c493bdc7c 100644
--- a/shmem/unix/shm.c
+++ b/shmem/unix/shm.c
@@ -59,6 +59,74 @@
 #include "apr_user.h"
 #include "apr_strings.h"
 
+static apr_status_t shm_cleanup_owner(void *m_)
+{
+    apr_shm_t *m = (apr_shm_t *)m_;
+
+    /* anonymous shared memory */
+    if (m->filename == NULL) {
+#if APR_USE_SHMEM_MMAP_ZERO || APR_USE_SHMEM_MMAP_ANON
+        if (munmap(m->base, m->realsize) == -1) {
+            return errno;
+        }
+        return APR_SUCCESS;
+#endif
+#if APR_USE_SHMEM_SHMGET_ANON
+        if (shmdt(m->base) == -1) {
+            return errno;
+        }
+        /* This segment will automatically remove itself after all
+         * references have detached. */
+        return APR_SUCCESS;
+#endif
+    }
+
+    /* name-based shared memory */
+    else {
+#if APR_USE_SHMEM_MMAP_TMP
+        apr_status_t rv;
+
+        if (munmap(m->base, m->realsize) == -1) {
+            return errno;
+        }
+        rv = apr_file_remove(m->filename, m->pool);
+        if (rv != APR_SUCCESS) {
+            return rv;
+        }
+        return APR_SUCCESS;
+#endif
+#if APR_USE_SHMEM_MMAP_SHM
+        if (munmap(m->base, m->realsize) == -1) {
+            return errno;
+        }
+        if (shm_unlink(m->filename) == -1) {
+            return errno;
+        }
+        return APR_SUCCESS;
+#endif
+#if APR_USE_SHMEM_SHMGET
+        apr_status_t rv;
+
+        /* Indicate that the segment is to be destroyed as soon
+         * as all processes have detached. This also disallows any
+         * new attachments to the segment. */
+        if (shmctl(m->shmid, IPC_RMID, NULL) == -1) {
+            return errno;
+        }
+        if (shmdt(m->base) == -1) {
+            return errno;
+        }
+        rv = apr_file_remove(m->filename, m->pool);
+        if (rv != APR_SUCCESS) {
+            return rv;
+        }
+        return APR_SUCCESS;
+#endif
+    }
+
+    return APR_ENOTIMPL;
+}
+
 APR_DECLARE(apr_status_t) apr_shm_create(apr_shm_t **m,
                                          apr_size_t reqsize, 
                                          const char *filename,
@@ -126,6 +194,8 @@ APR_DECLARE(apr_status_t) apr_shm_create(apr_shm_t **m,
         /* metadata isn't usable */
         new_m->usable = new_m->base + sizeof(apr_size_t);
 
+        apr_pool_cleanup_register(new_m->pool, new_m, shm_cleanup_owner,
+                                  apr_pool_cleanup_null);
         *m = new_m;
         return APR_SUCCESS;
 
@@ -141,6 +211,8 @@ APR_DECLARE(apr_status_t) apr_shm_create(apr_shm_t **m,
         /* metadata isn't usable */
         new_m->usable = (char *)new_m->base + sizeof(apr_size_t);
 
+        apr_pool_cleanup_register(new_m->pool, new_m, shm_cleanup_owner,
+                                  apr_pool_cleanup_null);
         *m = new_m;
         return APR_SUCCESS;
 
@@ -185,6 +257,8 @@ APR_DECLARE(apr_status_t) apr_shm_create(apr_shm_t **m,
             return errno;
         }
 
+        apr_pool_cleanup_register(new_m->pool, new_m, shm_cleanup_owner,
+                                  apr_pool_cleanup_null);
         *m = new_m;
         return APR_SUCCESS;
 #endif /* APR_USE_SHMEM_SHMGET_ANON */
@@ -276,6 +350,8 @@ APR_DECLARE(apr_status_t) apr_shm_create(apr_shm_t **m,
         /* metadata isn't usable */
         new_m->usable = new_m->base + sizeof(apr_size_t);
 
+        apr_pool_cleanup_register(new_m->pool, new_m, shm_cleanup_owner,
+                                  apr_pool_cleanup_null);
         *m = new_m;
         return APR_SUCCESS;
 
@@ -330,6 +406,8 @@ APR_DECLARE(apr_status_t) apr_shm_create(apr_shm_t **m,
             return status;
         }
 
+        apr_pool_cleanup_register(new_m->pool, new_m, shm_cleanup_owner,
+                                  apr_pool_cleanup_null);
         *m = new_m; 
         return APR_SUCCESS;
 
@@ -341,63 +419,30 @@ APR_DECLARE(apr_status_t) apr_shm_create(apr_shm_t **m,
 
 APR_DECLARE(apr_status_t) apr_shm_destroy(apr_shm_t *m)
 {
-    /* anonymous shared memory */
+    apr_status_t rv = shm_cleanup_owner(m);
+    apr_pool_cleanup_kill(m->pool, m, shm_cleanup_owner);
+    return rv;
+}
+
+static apr_status_t shm_cleanup_attach(void *m_)
+{
+    apr_shm_t *m = (apr_shm_t *)m_;
+
     if (m->filename == NULL) {
-#if APR_USE_SHMEM_MMAP_ZERO || APR_USE_SHMEM_MMAP_ANON
-        if (munmap(m->base, m->realsize) == -1) {
-            return errno;
-        }
-        return APR_SUCCESS;
-#endif
-#if APR_USE_SHMEM_SHMGET_ANON
-        if (shmdt(m->base) == -1) {
-            return errno;
-        }
-        /* This segment will automatically remove itself after all
-         * references have detached. */
-        return APR_SUCCESS;
-#endif
+        /* It doesn't make sense to detach from an anonymous memory segment. */
+        return APR_EINVAL;
     }
-
-    /* name-based shared memory */
     else {
-#if APR_USE_SHMEM_MMAP_TMP
-        apr_status_t rv;
-
-        if (munmap(m->base, m->realsize) == -1) {
-            return errno;
-        }
-        rv = apr_file_remove(m->filename, m->pool);
-        if (rv != APR_SUCCESS) {
-            return rv;
-        }
-        return APR_SUCCESS;
-#endif
-#if APR_USE_SHMEM_MMAP_SHM
+#if APR_USE_SHMEM_MMAP_TMP || APR_USE_SHMEM_MMAP_SHM
         if (munmap(m->base, m->realsize) == -1) {
             return errno;
         }
-        if (shm_unlink(m->filename) == -1) {
-            return errno;
-        }
         return APR_SUCCESS;
-#endif
+#endif /* APR_USE_SHMEM_MMAP_TMP || APR_USE_SHMEM_MMAP_SHM */
 #if APR_USE_SHMEM_SHMGET
-        apr_status_t rv;
-
-        /* Indicate that the segment is to be destroyed as soon
-         * as all processes have detached. This also disallows any
-         * new attachments to the segment. */
-        if (shmctl(m->shmid, IPC_RMID, NULL) == -1) {
-            return errno;
-        }
         if (shmdt(m->base) == -1) {
             return errno;
         }
-        rv = apr_file_remove(m->filename, m->pool);
-        if (rv != APR_SUCCESS) {
-            return rv;
-        }
         return APR_SUCCESS;
 #endif
     }
@@ -470,6 +515,8 @@ APR_DECLARE(apr_status_t) apr_shm_attach(apr_shm_t **m,
         /* metadata isn't usable */
         new_m->usable = new_m->base + sizeof(apr_size_t);
 
+        apr_pool_cleanup_register(new_m->pool, new_m, shm_cleanup_attach,
+                                  apr_pool_cleanup_null);
         *m = new_m;
         return APR_SUCCESS;
 
@@ -519,6 +566,8 @@ APR_DECLARE(apr_status_t) apr_shm_attach(apr_shm_t **m,
         new_m->usable = new_m->base;
         new_m->realsize = new_m->reqsize;
 
+        apr_pool_cleanup_register(new_m->pool, new_m, shm_cleanup_attach,
+                                  apr_pool_cleanup_null);
         *m = new_m;
         return APR_SUCCESS;
 
@@ -530,26 +579,9 @@ APR_DECLARE(apr_status_t) apr_shm_attach(apr_shm_t **m,
 
 APR_DECLARE(apr_status_t) apr_shm_detach(apr_shm_t *m)
 {
-    if (m->filename == NULL) {
-        /* It doesn't make sense to detach from an anonymous memory segment. */
-        return APR_EINVAL;
-    }
-    else {
-#if APR_USE_SHMEM_MMAP_TMP || APR_USE_SHMEM_MMAP_SHM
-        if (munmap(m->base, m->realsize) == -1) {
-            return errno;
-        }
-        return APR_SUCCESS;
-#endif /* APR_USE_SHMEM_MMAP_TMP || APR_USE_SHMEM_MMAP_SHM */
-#if APR_USE_SHMEM_SHMGET
-        if (shmdt(m->base) == -1) {
-            return errno;
-        }
-        return APR_SUCCESS;
-#endif
-    }
-
-    return APR_ENOTIMPL;
+    apr_status_t rv = shm_cleanup_attach(m);
+    apr_pool_cleanup_kill(m->pool, m, shm_cleanup_attach);
+    return rv;
 }
 
 APR_DECLARE(void *) apr_shm_baseaddr_get(const apr_shm_t *m)