/* 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.
*/
/* Memory handler for a plain memory divided in slot.
* This one uses plain memory.
*/
#include "ap_slotmem.h"
#define AP_SLOTMEM_IS_PREGRAB(t) (t->type & AP_SLOTMEM_TYPE_PREGRAB)
struct ap_slotmem_instance_t {
char *name; /* per segment name */
void *base; /* data set start */
apr_size_t size; /* size of each memory slot */
unsigned int num; /* number of mem slots */
apr_pool_t *gpool; /* per segment global pool */
char *inuse; /* in-use flag table*/
ap_slotmem_type_t type; /* type-specific flags */
struct ap_slotmem_instance_t *next; /* location of next allocated segment */
};
/* global pool and list of slotmem we are handling */
static struct ap_slotmem_instance_t *globallistmem = NULL;
static apr_pool_t *gpool = NULL;
static apr_status_t slotmem_do(ap_slotmem_instance_t *mem, ap_slotmem_callback_fn_t *func, void *data, apr_pool_t *pool)
{
unsigned int i;
char *ptr;
char *inuse;
apr_status_t retval = APR_SUCCESS;
if (!mem)
return APR_ENOSHMAVAIL;
ptr = (char *)mem->base;
inuse = mem->inuse;
for (i = 0; i < mem->num; i++, inuse++) {
if (!AP_SLOTMEM_IS_PREGRAB(mem) ||
(AP_SLOTMEM_IS_PREGRAB(mem) && *inuse)) {
retval = func((void *) ptr, data, pool);
if (retval != APR_SUCCESS)
break;
}
ptr += mem->size;
}
return retval;
}
static apr_status_t slotmem_create(ap_slotmem_instance_t **new, const char *name, apr_size_t item_size, unsigned int item_num, ap_slotmem_type_t type, apr_pool_t *pool)
{
ap_slotmem_instance_t *res;
ap_slotmem_instance_t *next = globallistmem;
apr_size_t basesize = (item_size * item_num);
const char *fname;
if (name) {
if (name[0] == ':')
fname = name;
else
fname = ap_runtime_dir_relative(pool, name);
/* first try to attach to existing slotmem */
if (next) {
for (;;) {
if (strcmp(next->name, fname) == 0) {
/* we already have it */
*new = next;
return APR_SUCCESS;
}
if (!next->next) {
break;
}
next = next->next;
}
}
}
else
fname = "anonymous";
/* create the memory using the gpool */
res = (ap_slotmem_instance_t *) apr_pcalloc(gpool, sizeof(ap_slotmem_instance_t));
res->base = apr_pcalloc(gpool, basesize + (item_num * sizeof(char)));
if (!res->base)
return APR_ENOSHMAVAIL;
/* For the chained slotmem stuff */
res->name = apr_pstrdup(gpool, fname);
res->size = item_size;
res->num = item_num;
res->next = NULL;
res->type = type;
res->inuse = (char *)res->base + basesize;
if (globallistmem == NULL)
globallistmem = res;
else
next->next = res;
*new = res;
return APR_SUCCESS;
}
static apr_status_t slotmem_attach(ap_slotmem_instance_t **new, const char *name, apr_size_t *item_size, unsigned int *item_num, apr_pool_t *pool)
{
ap_slotmem_instance_t *next = globallistmem;
const char *fname;
if (name) {
if (name[0] == ':')
fname = name;
else
fname = ap_runtime_dir_relative(pool, name);
}
else
return APR_ENOSHMAVAIL;
/* first try to attach to existing slotmem */
while (next) {
if (strcmp(next->name, fname) == 0) {
/* we already have it */
*new = next;
*item_size = next->size;
*item_num = next->num;
return APR_SUCCESS;
}
next = next->next;
}
return APR_ENOSHMAVAIL;
}
static apr_status_t slotmem_dptr(ap_slotmem_instance_t *score, unsigned int id, void **mem)
{
char *ptr;
if (!score)
return APR_ENOSHMAVAIL;
if (id >= score->num)
return APR_EINVAL;
ptr = (char *)score->base + score->size * id;
if (!ptr)
return APR_ENOSHMAVAIL;
*mem = ptr;
return APR_SUCCESS;
}
static apr_status_t slotmem_get(ap_slotmem_instance_t *slot, unsigned int id, unsigned char *dest, apr_size_t dest_len)
{
void *ptr;
char *inuse;
apr_status_t ret;
if (!slot) {
return APR_ENOSHMAVAIL;
}
inuse = slot->inuse + id;
if (id >= slot->num) {
return APR_EINVAL;
}
if (AP_SLOTMEM_IS_PREGRAB(slot) && !*inuse) {
return APR_NOTFOUND;
}
ret = slotmem_dptr(slot, id, &ptr);
if (ret != APR_SUCCESS) {
return ret;
}
*inuse=1;
memcpy(dest, ptr, dest_len); /* bounds check? */
return APR_SUCCESS;
}
static apr_status_t slotmem_put(ap_slotmem_instance_t *slot, unsigned int id, unsigned char *src, apr_size_t src_len)
{
void *ptr;
char *inuse;
apr_status_t ret;
if (!slot) {
return APR_ENOSHMAVAIL;
}
inuse = slot->inuse + id;
if (id >= slot->num) {
return APR_EINVAL;
}
if (AP_SLOTMEM_IS_PREGRAB(slot) && !*inuse) {
return APR_NOTFOUND;
}
ret = slotmem_dptr(slot, id, &ptr);
if (ret != APR_SUCCESS) {
return ret;
}
*inuse=1;
memcpy(ptr, src, src_len); /* bounds check? */
return APR_SUCCESS;
}
static unsigned int slotmem_num_slots(ap_slotmem_instance_t *slot)
{
return slot->num;
}
static unsigned int slotmem_num_free_slots(ap_slotmem_instance_t *slot)
{
unsigned int i, counter=0;
char *inuse = slot->inuse;
for (i = 0; i < slot->num; i++, inuse++) {
if (!*inuse)
counter++;
}
return counter;
}
static apr_size_t slotmem_slot_size(ap_slotmem_instance_t *slot)
{
return slot->size;
}
/*
* XXXX: if !AP_SLOTMEM_IS_PREGRAB, then still worry about
* inuse for grab and return?
*/
static apr_status_t slotmem_grab(ap_slotmem_instance_t *slot, unsigned int *id)
{
unsigned int i;
char *inuse;
if (!slot) {
return APR_ENOSHMAVAIL;
}
inuse = slot->inuse;
for (i = 0; i < slot->num; i++, inuse++) {
if (!*inuse) {
break;
}
}
if (i >= slot->num) {
return APR_EINVAL;
}
*inuse = 1;
*id = i;
return APR_SUCCESS;
}
static apr_status_t slotmem_fgrab(ap_slotmem_instance_t *slot, unsigned int id)
{
char *inuse;
if (!slot) {
return APR_ENOSHMAVAIL;
}
if (id >= slot->num) {
return APR_EINVAL;
}
inuse = slot->inuse + id;
*inuse = 1;
return APR_SUCCESS;
}
static apr_status_t slotmem_release(ap_slotmem_instance_t *slot, unsigned int id)
{
char *inuse;
if (!slot) {
return APR_ENOSHMAVAIL;
}
inuse = slot->inuse;
if (id >= slot->num) {
return APR_EINVAL;
}
if (!inuse[id] ) {
return APR_NOTFOUND;
}
inuse[id] = 0;
return APR_SUCCESS;
}
static const ap_slotmem_provider_t storage = {
"plainmem",
&slotmem_do,
&slotmem_create,
&slotmem_attach,
&slotmem_dptr,
&slotmem_get,
&slotmem_put,
&slotmem_num_slots,
&slotmem_num_free_slots,
&slotmem_slot_size,
&slotmem_grab,
&slotmem_release,
&slotmem_fgrab
};
static int pre_config(apr_pool_t *p, apr_pool_t *plog,
apr_pool_t *ptemp)
{
gpool = p;
return OK;
}
static void ap_slotmem_plain_register_hook(apr_pool_t *p)
{
/* XXX: static const char * const prePos[] = { "mod_slotmem.c", NULL }; */
ap_register_provider(p, AP_SLOTMEM_PROVIDER_GROUP, "plain",
AP_SLOTMEM_PROVIDER_VERSION, &storage);
ap_hook_pre_config(pre_config, NULL, NULL, APR_HOOK_MIDDLE);
}
AP_DECLARE_MODULE(slotmem_plain) = {
STANDARD20_MODULE_STUFF,
NULL, /* create per-directory config structure */
NULL, /* merge per-directory config structures */
NULL, /* create per-server config structure */
NULL, /* merge per-server config structures */
NULL, /* command apr_table_t */
ap_slotmem_plain_register_hook /* register hooks */
};