summaryrefslogtreecommitdiffstats
path: root/examples/deflate.c
blob: 8343b165ad75b8db0bcdaebdc97bd39318d3b760 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
/*
 * nghttp2 - HTTP/2 C Library
 *
 * Copyright (c) 2014 Tatsuhiro Tsujikawa
 *
 * Permission is hereby granted, free of charge, to any person obtaining
 * a copy of this software and associated documentation files (the
 * "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sublicense, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to
 * the following conditions:
 *
 * The above copyright notice and this permission notice shall be
 * included in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
 * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */
#ifdef HAVE_CONFIG_H
#  include <config.h>
#endif /* !HAVE_CONFIG_H */

#include <stdio.h>
#include <string.h>

#define NGHTTP2_NO_SSIZE_T
#include <nghttp2/nghttp2.h>

#define MAKE_NV(K, V)                                                          \
  {                                                                            \
    (uint8_t *)K, (uint8_t *)V, sizeof(K) - 1, sizeof(V) - 1,                  \
        NGHTTP2_NV_FLAG_NONE                                                   \
  }

static void deflate(nghttp2_hd_deflater *deflater,
                    nghttp2_hd_inflater *inflater, const nghttp2_nv *const nva,
                    size_t nvlen);

static int inflate_header_block(nghttp2_hd_inflater *inflater, uint8_t *in,
                                size_t inlen, int final);

int main(void) {
  int rv;
  nghttp2_hd_deflater *deflater;
  nghttp2_hd_inflater *inflater;
  /* Define 1st header set.  This is looks like a HTTP request. */
  nghttp2_nv nva1[] = {
      MAKE_NV(":scheme", "https"), MAKE_NV(":authority", "example.org"),
      MAKE_NV(":path", "/"), MAKE_NV("user-agent", "libnghttp2"),
      MAKE_NV("accept-encoding", "gzip, deflate")};
  /* Define 2nd header set */
  nghttp2_nv nva2[] = {MAKE_NV(":scheme", "https"),
                       MAKE_NV(":authority", "example.org"),
                       MAKE_NV(":path", "/stylesheet/style.css"),
                       MAKE_NV("user-agent", "libnghttp2"),
                       MAKE_NV("accept-encoding", "gzip, deflate"),
                       MAKE_NV("referer", "https://example.org")};

  rv = nghttp2_hd_deflate_new(&deflater, 4096);

  if (rv != 0) {
    fprintf(stderr, "nghttp2_hd_deflate_init failed with error: %s\n",
            nghttp2_strerror(rv));
    exit(EXIT_FAILURE);
  }

  rv = nghttp2_hd_inflate_new(&inflater);

  if (rv != 0) {
    fprintf(stderr, "nghttp2_hd_inflate_init failed with error: %s\n",
            nghttp2_strerror(rv));
    exit(EXIT_FAILURE);
  }

  /* Encode and decode 1st header set */
  deflate(deflater, inflater, nva1, sizeof(nva1) / sizeof(nva1[0]));

  /* Encode and decode 2nd header set, using differential encoding
     using state after encoding 1st header set. */
  deflate(deflater, inflater, nva2, sizeof(nva2) / sizeof(nva2[0]));

  nghttp2_hd_inflate_del(inflater);
  nghttp2_hd_deflate_del(deflater);

  return 0;
}

static void deflate(nghttp2_hd_deflater *deflater,
                    nghttp2_hd_inflater *inflater, const nghttp2_nv *const nva,
                    size_t nvlen) {
  nghttp2_ssize rv;
  uint8_t *buf;
  size_t buflen;
  size_t outlen;
  size_t i;
  size_t sum;

  sum = 0;

  for (i = 0; i < nvlen; ++i) {
    sum += nva[i].namelen + nva[i].valuelen;
  }

  printf("Input (%zu byte(s)):\n\n", sum);

  for (i = 0; i < nvlen; ++i) {
    fwrite(nva[i].name, 1, nva[i].namelen, stdout);
    printf(": ");
    fwrite(nva[i].value, 1, nva[i].valuelen, stdout);
    printf("\n");
  }

  buflen = nghttp2_hd_deflate_bound(deflater, nva, nvlen);
  buf = malloc(buflen);

  rv = nghttp2_hd_deflate_hd2(deflater, buf, buflen, nva, nvlen);

  if (rv < 0) {
    fprintf(stderr, "nghttp2_hd_deflate_hd2() failed with error: %s\n",
            nghttp2_strerror((int)rv));

    free(buf);

    exit(EXIT_FAILURE);
  }

  outlen = (size_t)rv;

  printf("\nDeflate (%zu byte(s), ratio %.02f):\n\n", outlen,
         sum == 0 ? 0 : (double)outlen / (double)sum);

  for (i = 0; i < outlen; ++i) {
    if ((i & 0x0fu) == 0) {
      printf("%08zX: ", i);
    }

    printf("%02X ", buf[i]);

    if (((i + 1) & 0x0fu) == 0) {
      printf("\n");
    }
  }

  printf("\n\nInflate:\n\n");

  /* We pass 1 to final parameter, because buf contains whole deflated
     header data. */
  rv = inflate_header_block(inflater, buf, outlen, 1);

  if (rv != 0) {
    free(buf);

    exit(EXIT_FAILURE);
  }

  printf("\n-----------------------------------------------------------"
         "--------------------\n");

  free(buf);
}

int inflate_header_block(nghttp2_hd_inflater *inflater, uint8_t *in,
                         size_t inlen, int final) {
  nghttp2_ssize rv;

  for (;;) {
    nghttp2_nv nv;
    int inflate_flags = 0;
    size_t proclen;

    rv =
        nghttp2_hd_inflate_hd3(inflater, &nv, &inflate_flags, in, inlen, final);

    if (rv < 0) {
      fprintf(stderr, "inflate failed with error code %td", rv);
      return -1;
    }

    proclen = (size_t)rv;

    in += proclen;
    inlen -= proclen;

    if (inflate_flags & NGHTTP2_HD_INFLATE_EMIT) {
      fwrite(nv.name, 1, nv.namelen, stderr);
      fprintf(stderr, ": ");
      fwrite(nv.value, 1, nv.valuelen, stderr);
      fprintf(stderr, "\n");
    }

    if (inflate_flags & NGHTTP2_HD_INFLATE_FINAL) {
      nghttp2_hd_inflate_end_headers(inflater);
      break;
    }

    if ((inflate_flags & NGHTTP2_HD_INFLATE_EMIT) == 0 && inlen == 0) {
      break;
    }
  }

  return 0;
}