2 * Copyright (c) 2008, 2009, 2010, 2011, 2012, 2013, 2016 Nicira, Inc.
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at:
8 * http://www.apache.org/licenses/LICENSE-2.0
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.
21 #include "dynamic-string.h"
22 #include "netdev-dpdk.h"
26 ofpbuf_init__(struct ofpbuf *b, size_t allocated, enum ofpbuf_source source)
28 b->allocated = allocated;
32 list_poison(&b->list_node);
36 ofpbuf_use__(struct ofpbuf *b, void *base, size_t allocated, size_t size,
37 enum ofpbuf_source source)
43 ofpbuf_init__(b, allocated, source);
46 /* Initializes 'b' as an empty ofpbuf that contains the 'allocated' bytes of
47 * memory starting at 'base'. 'base' should be the first byte of a region
48 * obtained from malloc(). It will be freed (with free()) if 'b' is resized or
51 ofpbuf_use(struct ofpbuf *b, void *base, size_t allocated)
53 ofpbuf_use__(b, base, allocated, 0, OFPBUF_MALLOC);
56 /* Converts ds into ofpbuf 'b'. 'b' contains the 'ds->allocated' bytes of
57 * memory starting at 'ds->string'. 'ds' should not be modified any more.
58 * The memory allocated for 'ds' will be freed (with free()) if 'b' is
59 * resized or freed. */
61 ofpbuf_use_ds(struct ofpbuf *b, const struct ds *ds)
63 ofpbuf_use__(b, ds->string, ds->allocated + 1, ds->length, OFPBUF_MALLOC);
66 /* Initializes 'b' as an empty ofpbuf that contains the 'allocated' bytes of
67 * memory starting at 'base'. 'base' should point to a buffer on the stack.
68 * (Nothing actually relies on 'base' being allocated on the stack. It could
69 * be static or malloc()'d memory. But stack space is the most common use
72 * 'base' should be appropriately aligned. Using an array of uint32_t or
73 * uint64_t for the buffer is a reasonable way to ensure appropriate alignment
74 * for 32- or 64-bit data.
76 * An ofpbuf operation that requires reallocating data will assert-fail if this
77 * function was used to initialize it. Thus, one need not call ofpbuf_uninit()
78 * on an ofpbuf initialized by this function (though doing so is harmless),
79 * because it is guaranteed that 'b' does not own any heap-allocated memory. */
81 ofpbuf_use_stack(struct ofpbuf *b, void *base, size_t allocated)
83 ofpbuf_use__(b, base, allocated, 0, OFPBUF_STACK);
86 /* Initializes 'b' as an empty ofpbuf that contains the 'allocated' bytes of
87 * memory starting at 'base'. 'base' should point to a buffer on the stack.
88 * (Nothing actually relies on 'base' being allocated on the stack. It could
89 * be static or malloc()'d memory. But stack space is the most common use
92 * 'base' should be appropriately aligned. Using an array of uint32_t or
93 * uint64_t for the buffer is a reasonable way to ensure appropriate alignment
94 * for 32- or 64-bit data.
96 * An ofpbuf operation that requires reallocating data will copy the provided
97 * buffer into a malloc()'d buffer. Thus, it is wise to call ofpbuf_uninit()
98 * on an ofpbuf initialized by this function, so that if it expanded into the
99 * heap, that memory is freed. */
101 ofpbuf_use_stub(struct ofpbuf *b, void *base, size_t allocated)
103 ofpbuf_use__(b, base, allocated, 0, OFPBUF_STUB);
106 /* Initializes 'b' as an ofpbuf whose data starts at 'data' and continues for
107 * 'size' bytes. This is appropriate for an ofpbuf that will be used to
108 * inspect existing data, without moving it around or reallocating it, and
109 * generally without modifying it at all.
111 * An ofpbuf operation that requires reallocating data will assert-fail if this
112 * function was used to initialize it. */
114 ofpbuf_use_const(struct ofpbuf *b, const void *data, size_t size)
116 ofpbuf_use__(b, CONST_CAST(void *, data), size, size, OFPBUF_STACK);
119 /* Initializes 'b' as an empty ofpbuf with an initial capacity of 'size'
122 ofpbuf_init(struct ofpbuf *b, size_t size)
124 ofpbuf_use(b, size ? xmalloc(size) : NULL, size);
127 /* Frees memory that 'b' points to. */
129 ofpbuf_uninit(struct ofpbuf *b)
132 if (b->source == OFPBUF_MALLOC) {
138 /* Frees memory that 'b' points to and allocates a new ofpbuf */
140 ofpbuf_reinit(struct ofpbuf *b, size_t size)
143 ofpbuf_init(b, size);
146 /* Creates and returns a new ofpbuf with an initial capacity of 'size'
149 ofpbuf_new(size_t size)
151 struct ofpbuf *b = xmalloc(sizeof *b);
152 ofpbuf_init(b, size);
156 /* Creates and returns a new ofpbuf with an initial capacity of 'size +
157 * headroom' bytes, reserving the first 'headroom' bytes as headroom. */
159 ofpbuf_new_with_headroom(size_t size, size_t headroom)
161 struct ofpbuf *b = ofpbuf_new(size + headroom);
162 ofpbuf_reserve(b, headroom);
166 /* Creates and returns a new ofpbuf that initially contains a copy of the
167 * 'buffer->size' bytes of data starting at 'buffer->data' with no headroom or
170 ofpbuf_clone(const struct ofpbuf *buffer)
172 return ofpbuf_clone_with_headroom(buffer, 0);
175 /* Creates and returns a new ofpbuf whose data are copied from 'buffer'. The
176 * returned ofpbuf will additionally have 'headroom' bytes of headroom. */
178 ofpbuf_clone_with_headroom(const struct ofpbuf *buffer, size_t headroom)
180 struct ofpbuf *new_buffer;
182 new_buffer = ofpbuf_clone_data_with_headroom(buffer->data,
185 if (buffer->header) {
186 ptrdiff_t data_delta = (char *)new_buffer->data - (char *)buffer->data;
188 new_buffer->header = (char *) buffer->header + data_delta;
190 new_buffer->msg = buffer->msg;
195 /* Creates and returns a new ofpbuf that initially contains a copy of the
196 * 'size' bytes of data starting at 'data' with no headroom or tailroom. */
198 ofpbuf_clone_data(const void *data, size_t size)
200 return ofpbuf_clone_data_with_headroom(data, size, 0);
203 /* Creates and returns a new ofpbuf that initially contains 'headroom' bytes of
204 * headroom followed by a copy of the 'size' bytes of data starting at
207 ofpbuf_clone_data_with_headroom(const void *data, size_t size, size_t headroom)
209 struct ofpbuf *b = ofpbuf_new_with_headroom(size, headroom);
210 ofpbuf_put(b, data, size);
215 ofpbuf_copy__(struct ofpbuf *b, uint8_t *new_base,
216 size_t new_headroom, size_t new_tailroom)
218 const uint8_t *old_base = b->base;
219 size_t old_headroom = ofpbuf_headroom(b);
220 size_t old_tailroom = ofpbuf_tailroom(b);
221 size_t copy_headroom = MIN(old_headroom, new_headroom);
222 size_t copy_tailroom = MIN(old_tailroom, new_tailroom);
224 memcpy(&new_base[new_headroom - copy_headroom],
225 &old_base[old_headroom - copy_headroom],
226 copy_headroom + b->size + copy_tailroom);
229 /* Reallocates 'b' so that it has exactly 'new_headroom' and 'new_tailroom'
230 * bytes of headroom and tailroom, respectively. */
232 ofpbuf_resize__(struct ofpbuf *b, size_t new_headroom, size_t new_tailroom)
234 void *new_base, *new_data;
235 size_t new_allocated;
237 new_allocated = new_headroom + b->size + new_tailroom;
241 if (new_headroom == ofpbuf_headroom(b)) {
242 new_base = xrealloc(b->base, new_allocated);
244 new_base = xmalloc(new_allocated);
245 ofpbuf_copy__(b, new_base, new_headroom, new_tailroom);
254 b->source = OFPBUF_MALLOC;
255 new_base = xmalloc(new_allocated);
256 ofpbuf_copy__(b, new_base, new_headroom, new_tailroom);
263 b->allocated = new_allocated;
266 new_data = (char *) new_base + new_headroom;
267 if (b->data != new_data) {
269 ptrdiff_t data_delta = (char *) b->header - (char *) b->data;
271 b->header = (char *) new_data + data_delta;
274 ptrdiff_t data_delta = (char *) b->msg - (char *) b->data;
276 b->msg = (char *) new_data + data_delta;
282 /* Ensures that 'b' has room for at least 'size' bytes at its tail end,
283 * reallocating and copying its data if necessary. Its headroom, if any, is
286 ofpbuf_prealloc_tailroom(struct ofpbuf *b, size_t size)
288 if (size > ofpbuf_tailroom(b)) {
289 ofpbuf_resize__(b, ofpbuf_headroom(b), MAX(size, 64));
293 /* Ensures that 'b' has room for at least 'size' bytes at its head,
294 * reallocating and copying its data if necessary. Its tailroom, if any, is
297 ofpbuf_prealloc_headroom(struct ofpbuf *b, size_t size)
299 if (size > ofpbuf_headroom(b)) {
300 ofpbuf_resize__(b, MAX(size, 64), ofpbuf_tailroom(b));
304 /* Trims the size of 'b' to fit its actual content, reducing its headroom and
305 * tailroom to 0, if any.
307 * Buffers not obtained from malloc() are not resized, since that wouldn't save
310 * Caller needs to updates 'b->header' and 'b->msg' so that they point to the
311 * same locations in the data. (If they pointed into the tailroom or headroom
312 * then they become invalid.)
316 ofpbuf_trim(struct ofpbuf *b)
318 if (b->source == OFPBUF_MALLOC
319 && (ofpbuf_headroom(b) || ofpbuf_tailroom(b))) {
320 ofpbuf_resize__(b, 0, 0);
324 /* If 'b' is shorter than 'length' bytes, pads its tail out with zeros to that
327 ofpbuf_padto(struct ofpbuf *b, size_t length)
329 if (b->size < length) {
330 ofpbuf_put_zeros(b, length - b->size);
334 /* Shifts all of the data within the allocated space in 'b' by 'delta' bytes.
335 * For example, a 'delta' of 1 would cause each byte of data to move one byte
336 * forward (from address 'p' to 'p+1'), and a 'delta' of -1 would cause each
337 * byte to move one byte backward (from 'p' to 'p-1').
339 * If used, user must make sure the 'header' and 'msg' pointers are updated
343 ofpbuf_shift(struct ofpbuf *b, int delta)
345 ovs_assert(delta > 0 ? delta <= ofpbuf_tailroom(b)
346 : delta < 0 ? -delta <= ofpbuf_headroom(b)
350 char *dst = (char *) b->data + delta;
351 memmove(dst, b->data, b->size);
356 /* Appends 'size' bytes of data to the tail end of 'b', reallocating and
357 * copying its data if necessary. Returns a pointer to the first byte of the
358 * new data, which is left uninitialized. */
360 ofpbuf_put_uninit(struct ofpbuf *b, size_t size)
363 ofpbuf_prealloc_tailroom(b, size);
369 /* Appends 'size' zeroed bytes to the tail end of 'b'. Data in 'b' is
370 * reallocated and copied if necessary. Returns a pointer to the first byte of
371 * the data's location in the ofpbuf. */
373 ofpbuf_put_zeros(struct ofpbuf *b, size_t size)
375 void *dst = ofpbuf_put_uninit(b, size);
376 memset(dst, 0, size);
380 /* Appends the 'size' bytes of data in 'p' to the tail end of 'b'. Data in 'b'
381 * is reallocated and copied if necessary. Returns a pointer to the first
382 * byte of the data's location in the ofpbuf. */
384 ofpbuf_put(struct ofpbuf *b, const void *p, size_t size)
386 void *dst = ofpbuf_put_uninit(b, size);
387 memcpy(dst, p, size);
391 /* Parses as many pairs of hex digits as possible (possibly separated by spaces
392 * or periods) from the beginning of 's', appending bytes for their values to
393 * 'b'. Returns the first character of 's' that is not the first of a pair of
394 * hex digits. If 'n' is nonnull, stores the number of bytes added to 'b' in
397 ofpbuf_put_hex(struct ofpbuf *b, const char *s, size_t *n)
399 size_t initial_size = b->size;
404 s += strspn(s, " .\t\r\n");
405 byte = hexits_value(s, 2, &ok);
408 *n = b->size - initial_size;
410 return CONST_CAST(char *, s);
413 ofpbuf_put(b, &byte, 1);
418 /* Reserves 'size' bytes of headroom so that they can be later allocated with
419 * ofpbuf_push_uninit() without reallocating the ofpbuf. */
421 ofpbuf_reserve(struct ofpbuf *b, size_t size)
423 ovs_assert(!b->size);
424 ofpbuf_prealloc_tailroom(b, size);
425 b->data = (char*)b->data + size;
428 /* Prefixes 'size' bytes to the head end of 'b', reallocating and copying its
429 * data if necessary. Returns a pointer to the first byte of the data's
430 * location in the ofpbuf. The new data is left uninitialized. */
432 ofpbuf_push_uninit(struct ofpbuf *b, size_t size)
434 ofpbuf_prealloc_headroom(b, size);
435 b->data = (char*)b->data - size;
440 /* Prefixes 'size' zeroed bytes to the head end of 'b', reallocating and
441 * copying its data if necessary. Returns a pointer to the first byte of the
442 * data's location in the ofpbuf. */
444 ofpbuf_push_zeros(struct ofpbuf *b, size_t size)
446 void *dst = ofpbuf_push_uninit(b, size);
447 memset(dst, 0, size);
451 /* Copies the 'size' bytes starting at 'p' to the head end of 'b', reallocating
452 * and copying its data if necessary. Returns a pointer to the first byte of
453 * the data's location in the ofpbuf. */
455 ofpbuf_push(struct ofpbuf *b, const void *p, size_t size)
457 void *dst = ofpbuf_push_uninit(b, size);
458 memcpy(dst, p, size);
462 /* Returns the data in 'b' as a block of malloc()'d memory and frees the buffer
463 * within 'b'. (If 'b' itself was dynamically allocated, e.g. with
464 * ofpbuf_new(), then it should still be freed with, e.g., ofpbuf_delete().) */
466 ofpbuf_steal_data(struct ofpbuf *b)
470 if (b->source == OFPBUF_MALLOC && b->data == b->base) {
473 p = xmemdup(b->data, b->size);
474 if (b->source == OFPBUF_MALLOC) {
485 /* Returns a string that describes some of 'b''s metadata plus a hex dump of up
486 * to 'maxbytes' from the start of the buffer. */
488 ofpbuf_to_string(const struct ofpbuf *b, size_t maxbytes)
493 ds_put_format(&s, "size=%"PRIu32", allocated=%"PRIu32", head=%"PRIuSIZE", tail=%"PRIuSIZE"\n",
494 b->size, b->allocated,
495 ofpbuf_headroom(b), ofpbuf_tailroom(b));
496 ds_put_hex_dump(&s, b->data, MIN(b->size, maxbytes), 0, false);
500 /* Removes each of the "struct ofpbuf"s on 'list' from the list and frees
503 ofpbuf_list_delete(struct ovs_list *list)
507 LIST_FOR_EACH_POP (b, list_node, list) {