Adding upstream version 1.7.2.upstream/1.7.2upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 731 insertions, 0 deletions

diff --git a/shmem/unix/shm.c b/shmem/unix/shm.c
new file mode 100644
index 0000000..f99afec
--- /dev/null
+++ b/shmem/unix/shm.c
@@ -0,0 +1,731 @@
+/* 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 "apr_arch_shm.h"
+#include "apr_arch_file_io.h"
+
+#include "apr_general.h"
+#include "apr_errno.h"
+#include "apr_user.h"
+#include "apr_strings.h"
+#include "apr_hash.h"
+
+#if APR_USE_SHMEM_MMAP_SHM
+/* 
+ *   For portable use, a shared memory object should be identified by a name of
+ *   the form /somename; that is, a null-terminated string of up to NAME_MAX
+ *   (i.e., 255) characters consisting of an initial slash, followed by one or
+ *   more characters, none of which are slashes.
+ */
+#ifndef NAME_MAX
+#define NAME_MAX 255
+#endif
+
+/* See proc_mutex.c and sem_open for the reason for all this! */
+static unsigned int rshash (const char *p) {
+    /* hash function from Robert Sedgwicks 'Algorithms in C' book */
+    unsigned int b    = 378551;
+    unsigned int a    = 63689;
+    unsigned int retval = 0;
+
+    for( ; *p; p++) {
+        retval = retval * a + (*p);
+        a *= b;
+    }
+
+    return retval;
+}
+
+static const char *make_shm_open_safe_name(const char *filename,
+                                           apr_pool_t *pool)
+{
+    apr_ssize_t flen;
+    unsigned int h1, h2;
+
+    if (filename == NULL) {
+        return NULL;
+    }
+
+    flen = strlen(filename);
+    h1 = (apr_hashfunc_default(filename, &flen) & 0xffffffff);
+    h2 = (rshash(filename) & 0xffffffff);
+    return apr_psprintf(pool, "/ShM.%xH%x", h1, h2);
+
+}
+#endif
+
+#if APR_USE_SHMEM_SHMGET
+static key_t our_ftok(const char *filename)
+{
+    /* to help avoid collisions while still using
+     * an easily recreated proj_id */
+    apr_ssize_t slen = strlen(filename);
+    return ftok(filename,
+                (int)apr_hashfunc_default(filename, &slen));
+}
+#endif
+
+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;
+#elif 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
+        if (munmap(m->base, m->realsize) == -1) {
+            return errno;
+        }
+        if (access(m->filename, F_OK)) {
+            return APR_SUCCESS;
+        }
+        else {
+            return apr_file_remove(m->filename, m->pool);
+        }
+#elif APR_USE_SHMEM_MMAP_SHM
+        if (munmap(m->base, m->realsize) == -1) {
+            return errno;
+        }
+        if (shm_unlink(make_shm_open_safe_name(m->filename, m->pool)) == -1 && errno != ENOENT) {
+            return errno;
+        }
+        return APR_SUCCESS;
+#elif APR_USE_SHMEM_SHMGET
+        /* 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 && errno != EINVAL) {
+            return errno;
+        }
+        if (shmdt(m->base) == -1) {
+            return errno;
+        }
+        if (access(m->filename, F_OK)) {
+            return APR_SUCCESS;
+        }
+        else {
+            return apr_file_remove(m->filename, m->pool);
+        }
+#else
+        return APR_ENOTIMPL;
+#endif
+    }
+}
+
+APR_DECLARE(apr_status_t) apr_shm_create(apr_shm_t **m,
+                                         apr_size_t reqsize, 
+                                         const char *filename,
+                                         apr_pool_t *pool)
+{
+    apr_shm_t *new_m;
+    apr_status_t status;
+#if APR_USE_SHMEM_SHMGET || APR_USE_SHMEM_SHMGET_ANON
+    struct shmid_ds shmbuf;
+    apr_uid_t uid;
+    apr_gid_t gid;
+#endif
+#if APR_USE_SHMEM_MMAP_TMP || APR_USE_SHMEM_MMAP_SHM || \
+    APR_USE_SHMEM_MMAP_ZERO
+    int tmpfd;
+#endif
+#if APR_USE_SHMEM_SHMGET
+    apr_size_t nbytes;
+#endif
+#if APR_USE_SHMEM_MMAP_ZERO || APR_USE_SHMEM_SHMGET || \
+    APR_USE_SHMEM_MMAP_TMP || APR_USE_SHMEM_MMAP_SHM
+    apr_file_t *file;   /* file where metadata is stored */
+#endif
+
+    /* Check if they want anonymous or name-based shared memory */
+    if (filename == NULL) {
+#if APR_USE_SHMEM_MMAP_ZERO || APR_USE_SHMEM_MMAP_ANON
+        new_m = apr_palloc(pool, sizeof(apr_shm_t));
+        new_m->pool = pool;
+        new_m->reqsize = reqsize;
+        new_m->realsize = reqsize + 
+            APR_ALIGN_DEFAULT(sizeof(apr_size_t)); /* room for metadata */
+        new_m->filename = NULL;
+    
+#if APR_USE_SHMEM_MMAP_ZERO
+        status = apr_file_open(&file, "/dev/zero", APR_READ | APR_WRITE, 
+                               APR_OS_DEFAULT, pool);
+        if (status != APR_SUCCESS) {
+            return status;
+        }
+        status = apr_os_file_get(&tmpfd, file);
+        if (status != APR_SUCCESS) {
+            return status;
+        }
+
+        new_m->base = mmap(NULL, new_m->realsize, PROT_READ|PROT_WRITE,
+                           MAP_SHARED, tmpfd, 0);
+        if (new_m->base == (void *)MAP_FAILED) {
+            return errno;
+        }
+
+        status = apr_file_close(file);
+        if (status != APR_SUCCESS) {
+            return status;
+        }
+
+        /* store the real size in the metadata */
+        *(apr_size_t*)(new_m->base) = new_m->realsize;
+        /* metadata isn't usable */
+        new_m->usable = (char *)new_m->base + APR_ALIGN_DEFAULT(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;
+
+#elif APR_USE_SHMEM_MMAP_ANON
+        new_m->base = mmap(NULL, new_m->realsize, PROT_READ|PROT_WRITE,
+                           MAP_ANON|MAP_SHARED, -1, 0);
+        if (new_m->base == (void *)MAP_FAILED) {
+            return errno;
+        }
+
+        /* store the real size in the metadata */
+        *(apr_size_t*)(new_m->base) = new_m->realsize;
+        /* metadata isn't usable */
+        new_m->usable = (char *)new_m->base + APR_ALIGN_DEFAULT(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;
+
+#endif /* APR_USE_SHMEM_MMAP_ZERO */
+#elif APR_USE_SHMEM_SHMGET_ANON
+        new_m = apr_palloc(pool, sizeof(apr_shm_t));
+        new_m->pool = pool;
+        new_m->reqsize = reqsize;
+        new_m->realsize = reqsize;
+        new_m->filename = NULL;
+        new_m->shmkey = IPC_PRIVATE;
+        if ((new_m->shmid = shmget(new_m->shmkey, new_m->realsize,
+                                   SHM_R | SHM_W | IPC_CREAT)) < 0) {
+            return errno;
+        }
+
+        if ((new_m->base = shmat(new_m->shmid, NULL, 0)) == (void *)-1) {
+            return errno;
+        }
+        new_m->usable = new_m->base;
+
+        if (shmctl(new_m->shmid, IPC_STAT, &shmbuf) == -1) {
+            return errno;
+        }
+        apr_uid_current(&uid, &gid, pool);
+        shmbuf.shm_perm.uid = uid;
+        shmbuf.shm_perm.gid = gid;
+        if (shmctl(new_m->shmid, IPC_SET, &shmbuf) == -1) {
+            return errno;
+        }
+
+        /* Remove the segment once use count hits zero.
+         * We will not attach to this segment again, since it is
+         * anonymous memory, so it is ok to mark it for deletion.
+         */
+        if (shmctl(new_m->shmid, IPC_RMID, NULL) == -1) {
+            return errno;
+        }
+
+        apr_pool_cleanup_register(new_m->pool, new_m, shm_cleanup_owner,
+                                  apr_pool_cleanup_null);
+        *m = new_m;
+        return APR_SUCCESS;
+#else
+        /* It is an error if they want anonymous memory but we don't have it. */
+        return APR_ENOTIMPL; /* requested anonymous but we don't have it */
+#endif
+    }
+
+    /* Name-based shared memory */
+    else {
+        new_m = apr_palloc(pool, sizeof(apr_shm_t));
+        new_m->pool = pool;
+        new_m->reqsize = reqsize;
+        new_m->filename = apr_pstrdup(pool, filename);
+#if APR_USE_SHMEM_MMAP_SHM
+        const char *shm_name = make_shm_open_safe_name(filename, pool);
+#endif
+#if APR_USE_SHMEM_MMAP_TMP || APR_USE_SHMEM_MMAP_SHM
+        new_m->realsize = reqsize + 
+            APR_ALIGN_DEFAULT(sizeof(apr_size_t)); /* room for metadata */
+        /* FIXME: Ignore error for now. *
+         * status = apr_file_remove(file, pool);*/
+        status = APR_SUCCESS;
+    
+#if APR_USE_SHMEM_MMAP_TMP
+        /* FIXME: Is APR_OS_DEFAULT sufficient? */
+        status = apr_file_open(&file, filename, 
+                               APR_READ | APR_WRITE | APR_CREATE | APR_EXCL,
+                               APR_OS_DEFAULT, pool);
+        if (status != APR_SUCCESS) {
+            return status;
+        }
+
+        status = apr_os_file_get(&tmpfd, file);
+        if (status != APR_SUCCESS) {
+            apr_file_close(file); /* ignore errors, we're failing */
+            apr_file_remove(new_m->filename, new_m->pool);
+            return status;
+        }
+
+        status = apr_file_trunc(file, new_m->realsize);
+        if (status != APR_SUCCESS && status != APR_ESPIPE) {
+            apr_file_close(file); /* ignore errors, we're failing */
+            apr_file_remove(new_m->filename, new_m->pool);
+            return status;
+        }
+
+        new_m->base = mmap(NULL, new_m->realsize, PROT_READ | PROT_WRITE,
+                           MAP_SHARED, tmpfd, 0);
+        /* FIXME: check for errors */
+
+        status = apr_file_close(file);
+        if (status != APR_SUCCESS) {
+            return status;
+        }
+#endif /* APR_USE_SHMEM_MMAP_TMP */
+#if APR_USE_SHMEM_MMAP_SHM
+        /* FIXME: SysV uses 0600... should we? */
+        tmpfd = shm_open(shm_name, O_RDWR | O_CREAT | O_EXCL, 0644);
+        if (tmpfd == -1) {
+            return errno;
+        }
+
+        status = apr_os_file_put(&file, &tmpfd,
+                                 APR_READ | APR_WRITE | APR_CREATE | APR_EXCL,
+                                 pool); 
+        if (status != APR_SUCCESS) {
+            return status;
+        }
+
+        status = apr_file_trunc(file, new_m->realsize);
+        if (status != APR_SUCCESS && status != APR_ESPIPE) {
+            shm_unlink(shm_name); /* we're failing, remove the object */
+            return status;
+        }
+        new_m->base = mmap(NULL, new_m->realsize, PROT_READ | PROT_WRITE,
+                           MAP_SHARED, tmpfd, 0);
+
+        /* FIXME: check for errors */
+
+        status = apr_file_close(file);
+        if (status != APR_SUCCESS) {
+            return status;
+        }
+#endif /* APR_USE_SHMEM_MMAP_SHM */
+
+        /* store the real size in the metadata */
+        *(apr_size_t*)(new_m->base) = new_m->realsize;
+        /* metadata isn't usable */
+        new_m->usable = (char *)new_m->base + APR_ALIGN_DEFAULT(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;
+
+#elif APR_USE_SHMEM_SHMGET
+        new_m->realsize = reqsize;
+
+        /* FIXME: APR_OS_DEFAULT is too permissive, switch to 600 I think. */
+        status = apr_file_open(&file, filename, 
+                               APR_FOPEN_WRITE | APR_FOPEN_CREATE | APR_FOPEN_EXCL,
+                               APR_OS_DEFAULT, pool);
+        if (status != APR_SUCCESS) {
+            return status;
+        }
+
+        /* ftok() (on solaris at least) requires that the file actually
+         * exist before calling ftok(). */
+        new_m->shmkey = our_ftok(filename);
+        if (new_m->shmkey == (key_t)-1) {
+            apr_file_close(file);
+            return errno;
+        }
+
+        if ((new_m->shmid = shmget(new_m->shmkey, new_m->realsize,
+                                   SHM_R | SHM_W | IPC_CREAT | IPC_EXCL)) < 0) {
+            apr_file_close(file);
+            return errno;
+        }
+
+        if ((new_m->base = shmat(new_m->shmid, NULL, 0)) == (void *)-1) {
+            apr_file_close(file);
+            return errno;
+        }
+        new_m->usable = new_m->base;
+
+        if (shmctl(new_m->shmid, IPC_STAT, &shmbuf) == -1) {
+            apr_file_close(file);
+            return errno;
+        }
+        apr_uid_current(&uid, &gid, pool);
+        shmbuf.shm_perm.uid = uid;
+        shmbuf.shm_perm.gid = gid;
+        if (shmctl(new_m->shmid, IPC_SET, &shmbuf) == -1) {
+            apr_file_close(file);
+            return errno;
+        }
+
+        nbytes = sizeof(reqsize);
+        status = apr_file_write(file, (const void *)&reqsize,
+                                &nbytes);
+        if (status != APR_SUCCESS) {
+            apr_file_close(file);
+            return status;
+        }
+        status = apr_file_close(file);
+        if (status != APR_SUCCESS) {
+            return status;
+        }
+
+        apr_pool_cleanup_register(new_m->pool, new_m, shm_cleanup_owner,
+                                  apr_pool_cleanup_null);
+        *m = new_m; 
+        return APR_SUCCESS;
+
+#else
+        return APR_ENOTIMPL;
+#endif
+    }
+}
+
+APR_DECLARE(apr_status_t) apr_shm_create_ex(apr_shm_t **m, 
+                                            apr_size_t reqsize, 
+                                            const char *filename, 
+                                            apr_pool_t *p,
+                                            apr_int32_t flags)
+{
+    return apr_shm_create(m, reqsize, filename, p);
+}
+
+APR_DECLARE(apr_status_t) apr_shm_remove(const char *filename,
+                                         apr_pool_t *pool)
+{
+#if APR_USE_SHMEM_SHMGET
+    apr_status_t status;
+    apr_file_t *file;  
+    key_t shmkey;
+    int shmid;
+#endif
+
+#if APR_USE_SHMEM_MMAP_TMP
+    return apr_file_remove(filename, pool);
+#elif APR_USE_SHMEM_MMAP_SHM
+    const char *shm_name = make_shm_open_safe_name(filename, pool);
+    if (shm_unlink(shm_name) == -1) {
+        return errno;
+    }
+    return APR_SUCCESS;
+#elif APR_USE_SHMEM_SHMGET
+    /* Presume that the file already exists; just open for writing */    
+    status = apr_file_open(&file, filename, APR_FOPEN_WRITE,
+                           APR_OS_DEFAULT, pool);
+    if (status) {
+        return status;
+    }
+
+    /* ftok() (on solaris at least) requires that the file actually
+     * exist before calling ftok(). */
+    shmkey = our_ftok(filename);
+    if (shmkey == (key_t)-1) {
+        goto shm_remove_failed;
+    }
+
+    apr_file_close(file);
+
+    if ((shmid = shmget(shmkey, 0, SHM_R | SHM_W)) < 0) {
+        goto shm_remove_failed;
+    }
+
+    /* 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(shmid, IPC_RMID, NULL) == -1) {
+        goto shm_remove_failed;
+    }
+    return apr_file_remove(filename, pool);
+
+shm_remove_failed:
+    status = errno;
+    /* ensure the file has been removed anyway. */
+    apr_file_remove(filename, pool);
+    return status;
+#else
+
+    /* No support for anonymous shm */
+    return APR_ENOTIMPL;
+#endif
+} 
+
+APR_DECLARE(apr_status_t) apr_shm_delete(apr_shm_t *m)
+{
+    if (m->filename) {
+        return apr_shm_remove(m->filename, m->pool);
+    }
+    else {
+        return APR_ENOTIMPL;
+    }
+} 
+
+APR_DECLARE(apr_status_t) apr_shm_destroy(apr_shm_t *m)
+{
+    return apr_pool_cleanup_run(m->pool, m, shm_cleanup_owner);
+}
+
+static apr_status_t shm_cleanup_attach(void *m_)
+{
+    apr_shm_t *m = (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;
+#elif APR_USE_SHMEM_SHMGET
+        if (shmdt(m->base) == -1) {
+            return errno;
+        }
+        return APR_SUCCESS;
+#else
+        return APR_ENOTIMPL;
+#endif
+    }
+}
+
+APR_DECLARE(apr_status_t) apr_shm_attach(apr_shm_t **m,
+                                         const char *filename,
+                                         apr_pool_t *pool)
+{
+    if (filename == NULL) {
+        /* It doesn't make sense to attach to a segment if you don't know
+         * the filename. */
+        return APR_EINVAL;
+    }
+    else {
+#if APR_USE_SHMEM_MMAP_TMP || APR_USE_SHMEM_MMAP_SHM
+        apr_shm_t *new_m;
+        apr_status_t status;
+        int tmpfd;
+        apr_file_t *file;   /* file where metadata is stored */
+        apr_size_t nbytes;
+
+        new_m = apr_palloc(pool, sizeof(apr_shm_t));
+        new_m->pool = pool;
+        new_m->filename = apr_pstrdup(pool, filename);
+#if APR_USE_SHMEM_MMAP_SHM
+        const char *shm_name = make_shm_open_safe_name(filename, pool);
+
+        /* FIXME: SysV uses 0600... should we? */
+        tmpfd = shm_open(shm_name, O_RDWR, 0644);
+        if (tmpfd == -1) {
+            return errno;
+        }
+
+        status = apr_os_file_put(&file, &tmpfd,
+                                 APR_READ | APR_WRITE,
+                                 pool); 
+        if (status != APR_SUCCESS) {
+            return status;
+        }
+
+#elif APR_USE_SHMEM_MMAP_TMP
+        status = apr_file_open(&file, filename, 
+                               APR_READ | APR_WRITE,
+                               APR_OS_DEFAULT, pool);
+        if (status != APR_SUCCESS) {
+            return status;
+        }
+        status = apr_os_file_get(&tmpfd, file);
+        if (status != APR_SUCCESS) {
+            return status;
+        }
+#else
+        return APR_ENOTIMPL;
+#endif
+
+        nbytes = sizeof(new_m->realsize);
+        status = apr_file_read(file, (void *)&(new_m->realsize),
+                               &nbytes);
+        if (status != APR_SUCCESS) {
+            return status;
+        }
+
+        status = apr_os_file_get(&tmpfd, file);
+        if (status != APR_SUCCESS) {
+            apr_file_close(file); /* ignore errors, we're failing */
+            apr_file_remove(new_m->filename, new_m->pool);
+            return status;
+        }
+
+        new_m->reqsize = new_m->realsize - sizeof(apr_size_t);
+
+        new_m->base = mmap(NULL, new_m->realsize, PROT_READ | PROT_WRITE,
+                           MAP_SHARED, tmpfd, 0);
+        /* FIXME: check for errors */
+        
+        status = apr_file_close(file);
+        if (status != APR_SUCCESS) {
+            return status;
+        }
+
+        /* metadata isn't part of the usable segment */
+        new_m->usable = (char *)new_m->base + APR_ALIGN_DEFAULT(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;
+
+#elif APR_USE_SHMEM_SHMGET
+        apr_shm_t *new_m;
+        apr_status_t status;
+        apr_file_t *file;   /* file where metadata is stored */
+        apr_size_t nbytes;
+
+        new_m = apr_palloc(pool, sizeof(apr_shm_t));
+
+        status = apr_file_open(&file, filename, 
+                               APR_FOPEN_READ, APR_OS_DEFAULT, pool);
+        if (status != APR_SUCCESS) {
+            return status;
+        }
+
+        nbytes = sizeof(new_m->reqsize);
+        status = apr_file_read(file, (void *)&(new_m->reqsize),
+                               &nbytes);
+        if (status != APR_SUCCESS) {
+            return status;
+        }
+        status = apr_file_close(file);
+        if (status != APR_SUCCESS) {
+            return status;
+        }
+
+        new_m->filename = apr_pstrdup(pool, filename);
+        new_m->pool = pool;
+        new_m->shmkey = our_ftok(filename);
+        if (new_m->shmkey == (key_t)-1) {
+            return errno;
+        }
+        if ((new_m->shmid = shmget(new_m->shmkey, 0, SHM_R | SHM_W)) == -1) {
+            return errno;
+        }
+        if ((new_m->base = shmat(new_m->shmid, NULL, 0)) == (void *)-1) {
+            return errno;
+        }
+        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;
+
+#else
+        return APR_ENOTIMPL;
+#endif
+    }
+}
+
+APR_DECLARE(apr_status_t) apr_shm_attach_ex(apr_shm_t **m,
+                                            const char *filename,
+                                            apr_pool_t *pool,
+                                            apr_int32_t flags)
+{
+    return apr_shm_attach(m, filename, pool);
+}
+
+APR_DECLARE(apr_status_t) apr_shm_detach(apr_shm_t *m)
+{
+    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)
+{
+    return m->usable;
+}
+
+APR_DECLARE(apr_size_t) apr_shm_size_get(const apr_shm_t *m)
+{
+    return m->reqsize;
+}
+
+APR_PERMS_SET_IMPLEMENT(shm)
+{
+#if APR_USE_SHMEM_SHMGET || APR_USE_SHMEM_SHMGET_ANON
+    struct shmid_ds shmbuf;
+    int shmid;
+    apr_shm_t *m = (apr_shm_t *)theshm;
+
+    if ((shmid = shmget(m->shmkey, 0, SHM_R | SHM_W)) == -1) {
+        return errno;
+    }
+    shmbuf.shm_perm.uid  = uid;
+    shmbuf.shm_perm.gid  = gid;
+    shmbuf.shm_perm.mode = apr_unix_perms2mode(perms);
+    if (shmctl(shmid, IPC_SET, &shmbuf) == -1) {
+        return errno;
+    }
+    return APR_SUCCESS;
+#else
+    return APR_ENOTIMPL;
+#endif
+}
+
+APR_POOL_IMPLEMENT_ACCESSOR(shm)
+
+APR_DECLARE(apr_status_t) apr_os_shm_get(apr_os_shm_t *osshm,
+                                         apr_shm_t *shm)
+{
+    return APR_ENOTIMPL;
+}
+
+APR_DECLARE(apr_status_t) apr_os_shm_put(apr_shm_t **m,
+                                         apr_os_shm_t *osshm,
+                                         apr_pool_t *pool)
+{
+    return APR_ENOTIMPL;
+}    
+