buckets/apr_buckets_simple.c

   1 /* Licensed to the Apache Software Foundation (ASF) under one or more
   2  * contributor license agreements.  See the NOTICE file distributed with
   3  * this work for additional information regarding copyright ownership.
   4  * The ASF licenses this file to You under the Apache License, Version 2.0
   5  * (the "License"); you may not use this file except in compliance with
   6  * the License.  You may obtain a copy of the License at
   7  *
   8  *     http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16
  17 #include "apr_buckets.h"
  18
  19 APU_DECLARE_NONSTD(apr_status_t) apr_bucket_simple_copy(apr_bucket *a,
  20                                                         apr_bucket **b)
  21 {
  22     *b = apr_bucket_alloc(sizeof(**b), a->list); /* XXX: check for failure? */
  23     **b = *a;
  24
  25     return APR_SUCCESS;
  26 }
  27
  28 APU_DECLARE_NONSTD(apr_status_t) apr_bucket_simple_split(apr_bucket *a,
  29                                                          apr_size_t point)
  30 {
  31     apr_bucket *b;
  32
  33     if (point > a->length) {
  34         return APR_EINVAL;
  35     }
  36
  37     apr_bucket_simple_copy(a, &b);
  38
  39     a->length  = point;
  40     b->length -= point;
  41     b->start  += point;
  42
  43     APR_BUCKET_INSERT_AFTER(a, b);
  44
  45     return APR_SUCCESS;
  46 }
  47
  48 static apr_status_t simple_bucket_read(apr_bucket *b, const char **str,
  49                                        apr_size_t *len, apr_read_type_e block)
  50 {
  51     *str = (char *)b->data + b->start;
  52     *len = b->length;
  53     return APR_SUCCESS;
  54 }
  55
  56 APU_DECLARE(apr_bucket *) apr_bucket_immortal_make(apr_bucket *b,
  57                                                    const char *buf,
  58                                                    apr_size_t length)
  59 {
  60     b->data   = (char *)buf;
  61     b->length = length;
  62     b->start  = 0;
  63     b->type   = &apr_bucket_type_immortal;
  64
  65     return b;
  66 }
  67
  68 APU_DECLARE(apr_bucket *) apr_bucket_immortal_create(const char *buf,
  69                                                      apr_size_t length,
  70                                                      apr_bucket_alloc_t *list)
  71 {
  72     apr_bucket *b = apr_bucket_alloc(sizeof(*b), list);
  73
  74     APR_BUCKET_INIT(b);
  75     b->free = apr_bucket_free;
  76     b->list = list;
  77     return apr_bucket_immortal_make(b, buf, length);
  78 }
  79
  80 /*
  81  * XXX: This function could do with some tweaking to reduce memory
  82  * usage in various cases, e.g. share buffers in the heap between all
  83  * the buckets that are set aside, or even spool set-aside data to
  84  * disk if it gets too voluminous (but if it does then that's probably
  85  * a bug elsewhere). There should probably be a apr_brigade_setaside()
  86  * function that co-ordinates the action of all the bucket setaside
  87  * functions to improve memory efficiency.
  88  */
  89 static apr_status_t transient_bucket_setaside(apr_bucket *b, apr_pool_t *pool)
  90 {
  91     b = apr_bucket_heap_make(b, (char *)b->data + b->start, b->length, NULL);
  92     if (b == NULL) {
  93         return APR_ENOMEM;
  94     }
  95     return APR_SUCCESS;
  96 }
  97
  98 APU_DECLARE(apr_bucket *) apr_bucket_transient_make(apr_bucket *b,
  99                                                     const char *buf,
 100                                                     apr_size_t length)
 101 {
 102     b->data   = (char *)buf;
 103     b->length = length;
 104     b->start  = 0;
 105     b->type   = &apr_bucket_type_transient;
 106     return b;
 107 }
 108
 109 APU_DECLARE(apr_bucket *) apr_bucket_transient_create(const char *buf,
 110                                                       apr_size_t length,
 111                                                       apr_bucket_alloc_t *list)
 112 {
 113     apr_bucket *b = apr_bucket_alloc(sizeof(*b), list);
 114
 115     APR_BUCKET_INIT(b);
 116     b->free = apr_bucket_free;
 117     b->list = list;
 118     return apr_bucket_transient_make(b, buf, length);
 119 }
 120
 121 const apr_bucket_type_t apr_bucket_type_immortal = {
 122     "IMMORTAL", 5, APR_BUCKET_DATA,
 123     apr_bucket_destroy_noop,
 124     simple_bucket_read,
 125     apr_bucket_setaside_noop,
 126     apr_bucket_simple_split,
 127     apr_bucket_simple_copy
 128 };
 129
 130 APU_DECLARE_DATA const apr_bucket_type_t apr_bucket_type_transient = {
 131     "TRANSIENT", 5, APR_BUCKET_DATA,
 132     apr_bucket_destroy_noop,
 133     simple_bucket_read,
 134     transient_bucket_setaside,
 135     apr_bucket_simple_split,
 136     apr_bucket_simple_copy
 137 };