1/* Copyright 2011 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
21
22typedef struct {
23    struct iovec *vecs;
24
25    /* Total number of buffer stored in the vecs var. */
26    int vecs_len;
27    /* Points to the first unread buffer. */
28    int current_vec;
29    /* First buffer offset. */
30    int offset;
31} iovec_context_t;
32
33serf_bucket_t *serf_bucket_iovec_create(
34    struct iovec vecs[],
35    int len,
36    serf_bucket_alloc_t *allocator)
37{
38    iovec_context_t *ctx;
39    int i;
40
41    ctx = serf_bucket_mem_alloc(allocator, sizeof(*ctx));
42    ctx->vecs = serf_bucket_mem_alloc(allocator, len * sizeof(struct iovec));
43    ctx->vecs_len = len;
44    ctx->current_vec = 0;
45    ctx->offset = 0;
46
47    /* copy all buffers to our iovec. */
48    for (i = 0; i < len; i++) {
49        ctx->vecs[i].iov_base = vecs[i].iov_base;
50        ctx->vecs[i].iov_len = vecs[i].iov_len;
51    }
52
53    return serf_bucket_create(&serf_bucket_type_iovec, allocator, ctx);
54}
55
56static apr_status_t serf_iovec_readline(serf_bucket_t *bucket,
57                                         int acceptable, int *found,
58                                         const char **data, apr_size_t *len)
59{
60    return APR_ENOTIMPL;
61}
62
63static apr_status_t serf_iovec_read_iovec(serf_bucket_t *bucket,
64                                          apr_size_t requested,
65                                          int vecs_size,
66                                          struct iovec *vecs,
67                                          int *vecs_used)
68{
69    iovec_context_t *ctx = bucket->data;
70
71    *vecs_used = 0;
72
73    /* copy the requested amount of buffers to the provided iovec. */
74    for (; ctx->current_vec < ctx->vecs_len; ctx->current_vec++) {
75        struct iovec vec = ctx->vecs[ctx->current_vec];
76        apr_size_t remaining;
77
78        if (requested != SERF_READ_ALL_AVAIL && requested <= 0)
79            break;
80        if (*vecs_used >= vecs_size)
81            break;
82
83        vecs[*vecs_used].iov_base = (char*)vec.iov_base + ctx->offset;
84        remaining = vec.iov_len - ctx->offset;
85
86        /* Less bytes requested than remaining in the current buffer. */
87        if (requested != SERF_READ_ALL_AVAIL && requested < remaining) {
88            vecs[*vecs_used].iov_len = requested;
89            ctx->offset += requested;
90            requested = 0;
91            (*vecs_used)++;
92            break;
93        } else {
94            /* Copy the complete buffer. */
95            vecs[*vecs_used].iov_len = remaining;
96            ctx->offset = 0;
97            if (requested != SERF_READ_ALL_AVAIL)
98                requested -= remaining;
99            (*vecs_used)++;
100        }
101    }
102
103    if (ctx->current_vec == ctx->vecs_len && !ctx->offset)
104        return APR_EOF;
105
106    return APR_SUCCESS;
107}
108
109static apr_status_t serf_iovec_read(serf_bucket_t *bucket,
110                                    apr_size_t requested,
111                                    const char **data, apr_size_t *len)
112{
113    struct iovec vec[1];
114    apr_status_t status;
115    int vecs_used;
116
117    status = serf_iovec_read_iovec(bucket, requested, 1, vec, &vecs_used);
118
119    if (vecs_used) {
120        *data = vec[0].iov_base;
121        *len = vec[0].iov_len;
122    } else {
123        *len = 0;
124    }
125
126    return status;
127}
128
129static apr_status_t serf_iovec_peek(serf_bucket_t *bucket,
130                                    const char **data,
131                                    apr_size_t *len)
132{
133    iovec_context_t *ctx = bucket->data;
134
135    if (ctx->current_vec >= ctx->vecs_len) {
136        *len = 0;
137        return APR_EOF;
138    }
139
140    /* Return the first unread buffer, don't bother combining all
141       remaining data. */
142    *data = ctx->vecs[ctx->current_vec].iov_base;
143    *len = ctx->vecs[ctx->current_vec].iov_len;
144
145    if (ctx->current_vec + 1 == ctx->vecs_len)
146        return APR_EOF;
147
148    return APR_SUCCESS;
149}
150
151static void serf_iovec_destroy(serf_bucket_t *bucket)
152{
153    iovec_context_t *ctx = bucket->data;
154
155    serf_bucket_mem_free(bucket->allocator, ctx->vecs);
156    serf_default_destroy_and_data(bucket);
157}
158
159
160const serf_bucket_type_t serf_bucket_type_iovec = {
161    "IOVEC",
162    serf_iovec_read,
163    serf_iovec_readline,
164    serf_iovec_read_iovec,
165    serf_default_read_for_sendfile,
166    serf_default_read_bucket,
167    serf_iovec_peek,
168    serf_iovec_destroy,
169};
170