summaryrefslogtreecommitdiffstats
path: root/lib/nghttp2_buf.h
blob: 95ff3706a232a3d67f49deb8992feea228b934a4 (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
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
/*
 * 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.
 */
#ifndef NGHTTP2_BUF_H
#define NGHTTP2_BUF_H

#ifdef HAVE_CONFIG_H
#  include <config.h>
#endif /* HAVE_CONFIG_H */

#include <nghttp2/nghttp2.h>

#include "nghttp2_int.h"
#include "nghttp2_mem.h"

typedef struct {
  /* This points to the beginning of the buffer. The effective range
     of buffer is [begin, end). */
  uint8_t *begin;
  /* This points to the memory one byte beyond the end of the
     buffer. */
  uint8_t *end;
  /* The position indicator for effective start of the buffer. pos <=
     last must be hold. */
  uint8_t *pos;
  /* The position indicator for effective one beyond of the end of the
     buffer. last <= end must be hold. */
  uint8_t *last;
  /* Mark arbitrary position in buffer [begin, end) */
  uint8_t *mark;
} nghttp2_buf;

#define nghttp2_buf_len(BUF) ((size_t)((BUF)->last - (BUF)->pos))
#define nghttp2_buf_avail(BUF) ((size_t)((BUF)->end - (BUF)->last))
#define nghttp2_buf_mark_avail(BUF) ((size_t)((BUF)->mark - (BUF)->last))
#define nghttp2_buf_cap(BUF) ((size_t)((BUF)->end - (BUF)->begin))

#define nghttp2_buf_pos_offset(BUF) ((size_t)((BUF)->pos - (BUF)->begin))
#define nghttp2_buf_last_offset(BUF) ((size_t)((BUF)->last - (BUF)->begin))

#define nghttp2_buf_shift_right(BUF, AMT)                                      \
  do {                                                                         \
    (BUF)->pos += AMT;                                                         \
    (BUF)->last += AMT;                                                        \
  } while (0)

#define nghttp2_buf_shift_left(BUF, AMT)                                       \
  do {                                                                         \
    (BUF)->pos -= AMT;                                                         \
    (BUF)->last -= AMT;                                                        \
  } while (0)

/*
 * Initializes the |buf|. No memory is allocated in this function. Use
 * nghttp2_buf_reserve() to allocate memory.
 */
void nghttp2_buf_init(nghttp2_buf *buf);

/*
 * Initializes the |buf| and allocates at least |initial| bytes of
 * memory.
 *
 * This function returns 0 if it succeeds, or one of the following
 * negative error codes:
 *
 * NGHTTP2_ERR_NOMEM
 *     Out of memory
 */
int nghttp2_buf_init2(nghttp2_buf *buf, size_t initial, nghttp2_mem *mem);

/*
 * Frees buffer in |buf|.
 */
void nghttp2_buf_free(nghttp2_buf *buf, nghttp2_mem *mem);

/*
 * Extends buffer so that nghttp2_buf_cap() returns at least
 * |new_cap|. If extensions took place, buffer pointers in |buf| will
 * change.
 *
 * This function returns 0 if it succeeds, or one of the following
 * negative error codes:
 *
 * NGHTTP2_ERR_NOMEM
 *     Out of memory
 */
int nghttp2_buf_reserve(nghttp2_buf *buf, size_t new_cap, nghttp2_mem *mem);

/*
 * Resets pos, last, mark member of |buf| to buf->begin.
 */
void nghttp2_buf_reset(nghttp2_buf *buf);

/*
 * Initializes |buf| using supplied buffer |begin| of length
 * |len|. Semantically, the application should not call *_reserve() or
 * nghttp2_free() functions for |buf|.
 */
void nghttp2_buf_wrap_init(nghttp2_buf *buf, uint8_t *begin, size_t len);

struct nghttp2_buf_chain;

typedef struct nghttp2_buf_chain nghttp2_buf_chain;

/* Chains 2 buffers */
struct nghttp2_buf_chain {
  /* Points to the subsequent buffer. NULL if there is no such
     buffer. */
  nghttp2_buf_chain *next;
  nghttp2_buf buf;
};

typedef struct {
  /* Points to the first buffer */
  nghttp2_buf_chain *head;
  /* Buffer pointer where write occurs. */
  nghttp2_buf_chain *cur;
  /* Memory allocator */
  nghttp2_mem *mem;
  /* The buffer capacity of each buf.  This field may be 0 if
     nghttp2_bufs is initialized by nghttp2_bufs_wrap_init* family
     functions. */
  size_t chunk_length;
  /* The maximum number of nghttp2_buf_chain */
  size_t max_chunk;
  /* The number of nghttp2_buf_chain allocated */
  size_t chunk_used;
  /* The number of nghttp2_buf_chain to keep on reset */
  size_t chunk_keep;
  /* pos offset from begin in each buffers. On initialization and
     reset, buf->pos and buf->last are positioned at buf->begin +
     offset. */
  size_t offset;
} nghttp2_bufs;

/*
 * This is the same as calling nghttp2_bufs_init2 with the given
 * arguments and offset = 0.
 */
int nghttp2_bufs_init(nghttp2_bufs *bufs, size_t chunk_length, size_t max_chunk,
                      nghttp2_mem *mem);

/*
 * This is the same as calling nghttp2_bufs_init3 with the given
 * arguments and chunk_keep = max_chunk.
 */
int nghttp2_bufs_init2(nghttp2_bufs *bufs, size_t chunk_length,
                       size_t max_chunk, size_t offset, nghttp2_mem *mem);

/*
 * Initializes |bufs|. Each buffer size is given in the
 * |chunk_length|.  The maximum number of buffers is given in the
 * |max_chunk|.  On reset, first |chunk_keep| buffers are kept and
 * remaining buffers are deleted.  Each buffer will have bufs->pos and
 * bufs->last shifted to left by |offset| bytes on creation and reset.
 *
 * This function allocates first buffer.  bufs->head and bufs->cur
 * will point to the first buffer after this call.
 *
 * This function returns 0 if it succeeds, or one of the following
 * negative error codes:
 *
 * NGHTTP2_ERR_NOMEM
 *     Out of memory.
 * NGHTTP2_ERR_INVALID_ARGUMENT
 *     chunk_keep is 0; or max_chunk < chunk_keep; or offset is too
 *     long.
 */
int nghttp2_bufs_init3(nghttp2_bufs *bufs, size_t chunk_length,
                       size_t max_chunk, size_t chunk_keep, size_t offset,
                       nghttp2_mem *mem);

/*
 * Frees any related resources to the |bufs|.
 */
void nghttp2_bufs_free(nghttp2_bufs *bufs);

/*
 * Initializes |bufs| using supplied buffer |begin| of length |len|.
 * The first buffer bufs->head uses buffer |begin|.  The buffer size
 * is fixed and no extra chunk buffer is allocated.  In other
 * words, max_chunk = chunk_keep = 1.  To free the resource allocated
 * for |bufs|, use nghttp2_bufs_wrap_free().
 *
 * Don't use the function which performs allocation, such as
 * nghttp2_bufs_realloc().
 *
 * This function returns 0 if it succeeds, or one of the following
 * negative error codes:
 *
 * NGHTTP2_ERR_NOMEM
 *     Out of memory.
 */
int nghttp2_bufs_wrap_init(nghttp2_bufs *bufs, uint8_t *begin, size_t len,
                           nghttp2_mem *mem);

/*
 * Initializes |bufs| using supplied |veclen| size of buf vector
 * |vec|.  The number of buffers is fixed and no extra chunk buffer is
 * allocated.  In other words, max_chunk = chunk_keep = |in_len|.  To
 * free the resource allocated for |bufs|, use
 * nghttp2_bufs_wrap_free().
 *
 * Don't use the function which performs allocation, such as
 * nghttp2_bufs_realloc().
 *
 * This function returns 0 if it succeeds, or one of the following
 * negative error codes:
 *
 * NGHTTP2_ERR_NOMEM
 *     Out of memory.
 */
int nghttp2_bufs_wrap_init2(nghttp2_bufs *bufs, const nghttp2_vec *vec,
                            size_t veclen, nghttp2_mem *mem);

/*
 * Frees any related resource to the |bufs|.  This function does not
 * free supplied buffer provided in nghttp2_bufs_wrap_init().
 */
void nghttp2_bufs_wrap_free(nghttp2_bufs *bufs);

/*
 * Reallocates internal buffer using |chunk_length|.  The max_chunk,
 * chunk_keep and offset do not change.  After successful allocation
 * of new buffer, previous buffers are deallocated without copying
 * anything into new buffers.  chunk_used is reset to 1.
 *
 * This function returns 0 if it succeeds, or one of the following
 * negative error codes:
 *
 * NGHTTP2_ERR_NOMEM
 *     Out of memory.
 * NGHTTP2_ERR_INVALID_ARGUMENT
 *     chunk_length < offset
 */
int nghttp2_bufs_realloc(nghttp2_bufs *bufs, size_t chunk_length);

/*
 * Appends the |data| of length |len| to the |bufs|. The write starts
 * at bufs->cur->buf.last. A new buffers will be allocated to store
 * all data.
 *
 * This function returns 0 if it succeeds, or one of the following
 * negative error codes:
 *
 * NGHTTP2_ERR_NOMEM
 *     Out of memory.
 * NGHTTP2_ERR_BUFFER_ERROR
 *     Out of buffer space.
 */
int nghttp2_bufs_add(nghttp2_bufs *bufs, const void *data, size_t len);

/*
 * Appends a single byte |b| to the |bufs|. The write starts at
 * bufs->cur->buf.last. A new buffers will be allocated to store all
 * data.
 *
 * This function returns 0 if it succeeds, or one of the following
 * negative error codes:
 *
 * NGHTTP2_ERR_NOMEM
 *     Out of memory.
 * NGHTTP2_ERR_BUFFER_ERROR
 *     Out of buffer space.
 */
int nghttp2_bufs_addb(nghttp2_bufs *bufs, uint8_t b);

/*
 * Behaves like nghttp2_bufs_addb(), but this does not update
 * buf->last pointer.
 */
int nghttp2_bufs_addb_hold(nghttp2_bufs *bufs, uint8_t b);

#define nghttp2_bufs_fast_addb(BUFS, B)                                        \
  do {                                                                         \
    *(BUFS)->cur->buf.last++ = B;                                              \
  } while (0)

#define nghttp2_bufs_fast_addb_hold(BUFS, B)                                   \
  do {                                                                         \
    *(BUFS)->cur->buf.last = B;                                                \
  } while (0)

/*
 * Performs bitwise-OR of |b| at bufs->cur->buf.last. A new buffers
 * will be allocated if necessary.
 *
 * This function returns 0 if it succeeds, or one of the following
 * negative error codes:
 *
 * NGHTTP2_ERR_NOMEM
 *     Out of memory.
 * NGHTTP2_ERR_BUFFER_ERROR
 *     Out of buffer space.
 */
int nghttp2_bufs_orb(nghttp2_bufs *bufs, uint8_t b);

/*
 * Behaves like nghttp2_bufs_orb(), but does not update buf->last
 * pointer.
 */
int nghttp2_bufs_orb_hold(nghttp2_bufs *bufs, uint8_t b);

#define nghttp2_bufs_fast_orb(BUFS, B)                                         \
  do {                                                                         \
    uint8_t **p = &(BUFS)->cur->buf.last;                                      \
    **p = (uint8_t)(**p | (B));                                                \
    ++(*p);                                                                    \
  } while (0)

#define nghttp2_bufs_fast_orb_hold(BUFS, B)                                    \
  do {                                                                         \
    uint8_t *p = (BUFS)->cur->buf.last;                                        \
    *p = (uint8_t)(*p | (B));                                                  \
  } while (0)

/*
 * Copies all data stored in |bufs| to the contiguous buffer.  This
 * function allocates the contiguous memory to store all data in
 * |bufs| and assigns it to |*out|.
 *
 * The contents of |bufs| is left unchanged.
 *
 * This function returns the length of copied data and assigns the
 * pointer to copied data to |*out| if it succeeds, or one of the
 * following negative error codes:
 *
 * NGHTTP2_ERR_NOMEM
 *     Out of memory
 */
nghttp2_ssize nghttp2_bufs_remove(nghttp2_bufs *bufs, uint8_t **out);

/*
 * Copies all data stored in |bufs| to |out|.  This function assumes
 * that the buffer space pointed by |out| has at least
 * nghttp2_bufs(bufs) bytes.
 *
 * The contents of |bufs| is left unchanged.
 *
 * This function returns the length of copied data.
 */
size_t nghttp2_bufs_remove_copy(nghttp2_bufs *bufs, uint8_t *out);

/*
 * Resets |bufs| and makes the buffers empty.
 */
void nghttp2_bufs_reset(nghttp2_bufs *bufs);

/*
 * Moves bufs->cur to bufs->cur->next.  If resulting bufs->cur is
 * NULL, this function allocates new buffers and bufs->cur points to
 * it.
 *
 * This function returns 0 if it succeeds, or one of the following
 * negative error codes:
 *
 * NGHTTP2_ERR_NOMEM
 *     Out of memory
 * NGHTTP2_ERR_BUFFER_ERROR
 *     Out of buffer space.
 */
int nghttp2_bufs_advance(nghttp2_bufs *bufs);

/* Sets bufs->cur to bufs->head */
#define nghttp2_bufs_rewind(BUFS)                                              \
  do {                                                                         \
    (BUFS)->cur = (BUFS)->head;                                                \
  } while (0)

/*
 * Move bufs->cur, from the current position, using next member, to
 * the last buf which has nghttp2_buf_len(buf) > 0 without seeing buf
 * which satisfies nghttp2_buf_len(buf) == 0.  If
 * nghttp2_buf_len(&bufs->cur->buf) == 0 or bufs->cur->next is NULL,
 * bufs->cur is unchanged.
 */
void nghttp2_bufs_seek_last_present(nghttp2_bufs *bufs);

/*
 * Returns nonzero if bufs->cur->next is not empty.
 */
int nghttp2_bufs_next_present(nghttp2_bufs *bufs);

#define nghttp2_bufs_cur_avail(BUFS) nghttp2_buf_avail(&(BUFS)->cur->buf)

/*
 * Returns the total buffer length of |bufs|.
 */
size_t nghttp2_bufs_len(nghttp2_bufs *bufs);

#endif /* NGHTTP2_BUF_H */