1/* Copyright 2002-2004 Justin Erenkrantz and Greg Stein
2 *
3 * Licensed under the Apache License, Version 2.0 (the "License");
4 * you may not use this file except in compliance with the License.
5 * You may obtain a copy of the License at
6 *
7 *     http://www.apache.org/licenses/LICENSE-2.0
8 *
9 * Unless required by applicable law or agreed to in writing, software
10 * distributed under the License is distributed on an "AS IS" BASIS,
11 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 * See the License for the specific language governing permissions and
13 * limitations under the License.
14 */
15
16#include <apr_pools.h>
17
18#include "serf.h"
19#include "serf_bucket_util.h"
20#include "serf_private.h"
21
22typedef struct {
23    serf_bucket_t *stream;
24    apr_uint64_t remaining;
25} limit_context_t;
26
27
28serf_bucket_t *serf_bucket_limit_create(
29    serf_bucket_t *stream, apr_uint64_t len, serf_bucket_alloc_t *allocator)
30{
31    limit_context_t *ctx;
32
33    ctx = serf_bucket_mem_alloc(allocator, sizeof(*ctx));
34    ctx->stream = stream;
35    ctx->remaining = len;
36
37    return serf_bucket_create(&serf_bucket_type_limit, allocator, ctx);
38}
39
40static apr_status_t serf_limit_read(serf_bucket_t *bucket,
41                                    apr_size_t requested,
42                                    const char **data, apr_size_t *len)
43{
44    limit_context_t *ctx = bucket->data;
45    apr_status_t status;
46
47    if (!ctx->remaining) {
48        *len = 0;
49        return APR_EOF;
50    }
51
52    if (requested == SERF_READ_ALL_AVAIL || requested > ctx->remaining) {
53        if (ctx->remaining <= REQUESTED_MAX) {
54            requested = (apr_size_t) ctx->remaining;
55        } else {
56            requested = REQUESTED_MAX;
57        }
58    }
59
60    status = serf_bucket_read(ctx->stream, requested, data, len);
61
62    if (!SERF_BUCKET_READ_ERROR(status)) {
63        ctx->remaining -= *len;
64    }
65
66    /* If we have met our limit and don't have a status, return EOF. */
67    if (!ctx->remaining && !status) {
68        status = APR_EOF;
69    }
70
71    return status;
72}
73
74static apr_status_t serf_limit_readline(serf_bucket_t *bucket,
75                                         int acceptable, int *found,
76                                         const char **data, apr_size_t *len)
77{
78    limit_context_t *ctx = bucket->data;
79    apr_status_t status;
80
81    if (!ctx->remaining) {
82        *len = 0;
83        return APR_EOF;
84    }
85
86    status = serf_bucket_readline(ctx->stream, acceptable, found, data, len);
87
88    if (!SERF_BUCKET_READ_ERROR(status)) {
89        ctx->remaining -= *len;
90    }
91
92    /* If we have met our limit and don't have a status, return EOF. */
93    if (!ctx->remaining && !status) {
94        status = APR_EOF;
95    }
96
97    return status;
98}
99
100static apr_status_t serf_limit_peek(serf_bucket_t *bucket,
101                                     const char **data,
102                                     apr_size_t *len)
103{
104    limit_context_t *ctx = bucket->data;
105
106    return serf_bucket_peek(ctx->stream, data, len);
107}
108
109static void serf_limit_destroy(serf_bucket_t *bucket)
110{
111    limit_context_t *ctx = bucket->data;
112
113    serf_bucket_destroy(ctx->stream);
114
115    serf_default_destroy_and_data(bucket);
116}
117
118const serf_bucket_type_t serf_bucket_type_limit = {
119    "LIMIT",
120    serf_limit_read,
121    serf_limit_readline,
122    serf_default_read_iovec,
123    serf_default_read_for_sendfile,
124    serf_default_read_bucket,
125    serf_limit_peek,
126    serf_limit_destroy,
127};
128