2 * Copyright (c) 2002-2007 Niels Provos <provos@citi.umich.edu>
3 * Copyright (c) 2007-2012 Niels Provos and Nick Mathewson
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. The name of the author may not be used to endorse or promote products
14 * derived from this software without specific prior written permission.
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28 #include "event2/event-config.h"
29 #include "evconfig-private.h"
37 #ifdef EVENT__HAVE_VASPRINTF
38 /* If we have vasprintf, we need to define _GNU_SOURCE before we include
39 * stdio.h. This comes from evconfig-private.h.
43 #include <sys/types.h>
45 #ifdef EVENT__HAVE_SYS_TIME_H
49 #ifdef EVENT__HAVE_SYS_SOCKET_H
50 #include <sys/socket.h>
53 #ifdef EVENT__HAVE_SYS_UIO_H
57 #ifdef EVENT__HAVE_SYS_IOCTL_H
58 #include <sys/ioctl.h>
61 #ifdef EVENT__HAVE_SYS_MMAN_H
65 #ifdef EVENT__HAVE_SYS_SENDFILE_H
66 #include <sys/sendfile.h>
68 #ifdef EVENT__HAVE_SYS_STAT_H
77 #ifdef EVENT__HAVE_STDARG_H
80 #ifdef EVENT__HAVE_UNISTD_H
85 #include "event2/event.h"
86 #include "event2/buffer.h"
87 #include "event2/buffer_compat.h"
88 #include "event2/bufferevent.h"
89 #include "event2/bufferevent_compat.h"
90 #include "event2/bufferevent_struct.h"
91 #include "event2/thread.h"
92 #include "log-internal.h"
93 #include "mm-internal.h"
94 #include "util-internal.h"
95 #include "evthread-internal.h"
96 #include "evbuffer-internal.h"
97 #include "bufferevent-internal.h"
99 /* some systems do not have MAP_FAILED */
101 #define MAP_FAILED ((void *)-1)
104 /* send file support */
105 #if defined(EVENT__HAVE_SYS_SENDFILE_H) && defined(EVENT__HAVE_SENDFILE) && defined(__linux__)
106 #define USE_SENDFILE 1
107 #define SENDFILE_IS_LINUX 1
108 #elif defined(EVENT__HAVE_SENDFILE) && defined(__FreeBSD__)
109 #define USE_SENDFILE 1
110 #define SENDFILE_IS_FREEBSD 1
111 #elif defined(EVENT__HAVE_SENDFILE) && defined(__APPLE__)
112 #define USE_SENDFILE 1
113 #define SENDFILE_IS_MACOSX 1
114 #elif defined(EVENT__HAVE_SENDFILE) && defined(__sun__) && defined(__svr4__)
115 #define USE_SENDFILE 1
116 #define SENDFILE_IS_SOLARIS 1
119 /* Mask of user-selectable callback flags. */
120 #define EVBUFFER_CB_USER_FLAGS 0xffff
121 /* Mask of all internal-use-only flags. */
122 #define EVBUFFER_CB_INTERNAL_FLAGS 0xffff0000
124 /* Flag set if the callback is using the cb_obsolete function pointer */
125 #define EVBUFFER_CB_OBSOLETE 0x00040000
127 /* evbuffer_chain support */
128 #define CHAIN_SPACE_PTR(ch) ((ch)->buffer + (ch)->misalign + (ch)->off)
129 #define CHAIN_SPACE_LEN(ch) ((ch)->flags & EVBUFFER_IMMUTABLE ? \
130 0 : (ch)->buffer_len - ((ch)->misalign + (ch)->off))
132 #define CHAIN_PINNED(ch) (((ch)->flags & EVBUFFER_MEM_PINNED_ANY) != 0)
133 #define CHAIN_PINNED_R(ch) (((ch)->flags & EVBUFFER_MEM_PINNED_R) != 0)
135 /* evbuffer_ptr support */
136 #define PTR_NOT_FOUND(ptr) do { \
138 (ptr)->internal_.chain = NULL; \
139 (ptr)->internal_.pos_in_chain = 0; \
142 static void evbuffer_chain_align(struct evbuffer_chain *chain);
143 static int evbuffer_chain_should_realign(struct evbuffer_chain *chain,
145 static void evbuffer_deferred_callback(struct event_callback *cb, void *arg);
146 static int evbuffer_ptr_memcmp(const struct evbuffer *buf,
147 const struct evbuffer_ptr *pos, const char *mem, size_t len);
148 static struct evbuffer_chain *evbuffer_expand_singlechain(struct evbuffer *buf,
150 static int evbuffer_ptr_subtract(struct evbuffer *buf, struct evbuffer_ptr *pos,
152 static int evbuffer_file_segment_materialize(struct evbuffer_file_segment *seg);
153 static inline void evbuffer_chain_incref(struct evbuffer_chain *chain);
155 static struct evbuffer_chain *
156 evbuffer_chain_new(size_t size)
158 struct evbuffer_chain *chain;
161 if (size > EVBUFFER_CHAIN_MAX - EVBUFFER_CHAIN_SIZE)
164 size += EVBUFFER_CHAIN_SIZE;
166 /* get the next largest memory that can hold the buffer */
167 if (size < EVBUFFER_CHAIN_MAX / 2) {
168 to_alloc = MIN_BUFFER_SIZE;
169 while (to_alloc < size) {
176 /* we get everything in one chunk */
177 if ((chain = mm_malloc(to_alloc)) == NULL)
180 memset(chain, 0, EVBUFFER_CHAIN_SIZE);
182 chain->buffer_len = to_alloc - EVBUFFER_CHAIN_SIZE;
184 /* this way we can manipulate the buffer to different addresses,
185 * which is required for mmap for example.
187 chain->buffer = EVBUFFER_CHAIN_EXTRA(unsigned char, chain);
195 evbuffer_chain_free(struct evbuffer_chain *chain)
197 EVUTIL_ASSERT(chain->refcnt > 0);
198 if (--chain->refcnt > 0) {
199 /* chain is still referenced by other chains */
203 if (CHAIN_PINNED(chain)) {
204 /* will get freed once no longer dangling */
206 chain->flags |= EVBUFFER_DANGLING;
210 /* safe to release chain, it's either a referencing
211 * chain or all references to it have been freed */
212 if (chain->flags & EVBUFFER_REFERENCE) {
213 struct evbuffer_chain_reference *info =
214 EVBUFFER_CHAIN_EXTRA(
215 struct evbuffer_chain_reference,
218 (*info->cleanupfn)(chain->buffer,
222 if (chain->flags & EVBUFFER_FILESEGMENT) {
223 struct evbuffer_chain_file_segment *info =
224 EVBUFFER_CHAIN_EXTRA(
225 struct evbuffer_chain_file_segment,
229 if (info->segment->is_mapping)
230 UnmapViewOfFile(chain->buffer);
232 evbuffer_file_segment_free(info->segment);
235 if (chain->flags & EVBUFFER_MULTICAST) {
236 struct evbuffer_multicast_parent *info =
237 EVBUFFER_CHAIN_EXTRA(
238 struct evbuffer_multicast_parent,
240 /* referencing chain is being freed, decrease
241 * refcounts of source chain and associated
242 * evbuffer (which get freed once both reach
244 EVUTIL_ASSERT(info->source != NULL);
245 EVUTIL_ASSERT(info->parent != NULL);
246 EVBUFFER_LOCK(info->source);
247 evbuffer_chain_free(info->parent);
248 evbuffer_decref_and_unlock_(info->source);
255 evbuffer_free_all_chains(struct evbuffer_chain *chain)
257 struct evbuffer_chain *next;
258 for (; chain; chain = next) {
260 evbuffer_chain_free(chain);
266 evbuffer_chains_all_empty(struct evbuffer_chain *chain)
268 for (; chain; chain = chain->next) {
275 /* The definition is needed for EVUTIL_ASSERT, which uses sizeof to avoid
276 "unused variable" warnings. */
277 static inline int evbuffer_chains_all_empty(struct evbuffer_chain *chain) {
282 /* Free all trailing chains in 'buf' that are neither pinned nor empty, prior
283 * to replacing them all with a new chain. Return a pointer to the place
284 * where the new chain will go.
286 * Internal; requires lock. The caller must fix up buf->last and buf->first
287 * as needed; they might have been freed.
289 static struct evbuffer_chain **
290 evbuffer_free_trailing_empty_chains(struct evbuffer *buf)
292 struct evbuffer_chain **ch = buf->last_with_datap;
293 /* Find the first victim chain. It might be *last_with_datap */
294 while ((*ch) && ((*ch)->off != 0 || CHAIN_PINNED(*ch)))
297 EVUTIL_ASSERT(evbuffer_chains_all_empty(*ch));
298 evbuffer_free_all_chains(*ch);
304 /* Add a single chain 'chain' to the end of 'buf', freeing trailing empty
305 * chains as necessary. Requires lock. Does not schedule callbacks.
308 evbuffer_chain_insert(struct evbuffer *buf,
309 struct evbuffer_chain *chain)
311 ASSERT_EVBUFFER_LOCKED(buf);
312 if (*buf->last_with_datap == NULL) {
313 /* There are no chains data on the buffer at all. */
314 EVUTIL_ASSERT(buf->last_with_datap == &buf->first);
315 EVUTIL_ASSERT(buf->first == NULL);
316 buf->first = buf->last = chain;
318 struct evbuffer_chain **chp;
319 chp = evbuffer_free_trailing_empty_chains(buf);
322 buf->last_with_datap = chp;
325 buf->total_len += chain->off;
328 static inline struct evbuffer_chain *
329 evbuffer_chain_insert_new(struct evbuffer *buf, size_t datlen)
331 struct evbuffer_chain *chain;
332 if ((chain = evbuffer_chain_new(datlen)) == NULL)
334 evbuffer_chain_insert(buf, chain);
339 evbuffer_chain_pin_(struct evbuffer_chain *chain, unsigned flag)
341 EVUTIL_ASSERT((chain->flags & flag) == 0);
342 chain->flags |= flag;
346 evbuffer_chain_unpin_(struct evbuffer_chain *chain, unsigned flag)
348 EVUTIL_ASSERT((chain->flags & flag) != 0);
349 chain->flags &= ~flag;
350 if (chain->flags & EVBUFFER_DANGLING)
351 evbuffer_chain_free(chain);
355 evbuffer_chain_incref(struct evbuffer_chain *chain)
363 struct evbuffer *buffer;
365 buffer = mm_calloc(1, sizeof(struct evbuffer));
369 LIST_INIT(&buffer->callbacks);
371 buffer->last_with_datap = &buffer->first;
377 evbuffer_set_flags(struct evbuffer *buf, ev_uint64_t flags)
380 buf->flags |= (ev_uint32_t)flags;
381 EVBUFFER_UNLOCK(buf);
386 evbuffer_clear_flags(struct evbuffer *buf, ev_uint64_t flags)
389 buf->flags &= ~(ev_uint32_t)flags;
390 EVBUFFER_UNLOCK(buf);
395 evbuffer_incref_(struct evbuffer *buf)
399 EVBUFFER_UNLOCK(buf);
403 evbuffer_incref_and_lock_(struct evbuffer *buf)
410 evbuffer_defer_callbacks(struct evbuffer *buffer, struct event_base *base)
412 EVBUFFER_LOCK(buffer);
413 buffer->cb_queue = base;
414 buffer->deferred_cbs = 1;
415 event_deferred_cb_init_(&buffer->deferred,
416 event_base_get_npriorities(base) / 2,
417 evbuffer_deferred_callback, buffer);
418 EVBUFFER_UNLOCK(buffer);
423 evbuffer_enable_locking(struct evbuffer *buf, void *lock)
425 #ifdef EVENT__DISABLE_THREAD_SUPPORT
432 EVTHREAD_ALLOC_LOCK(lock, EVTHREAD_LOCKTYPE_RECURSIVE);
447 evbuffer_set_parent_(struct evbuffer *buf, struct bufferevent *bev)
451 EVBUFFER_UNLOCK(buf);
455 evbuffer_run_callbacks(struct evbuffer *buffer, int running_deferred)
457 struct evbuffer_cb_entry *cbent, *next;
458 struct evbuffer_cb_info info;
460 ev_uint32_t mask, masked_val;
463 if (running_deferred) {
464 mask = EVBUFFER_CB_NODEFER|EVBUFFER_CB_ENABLED;
465 masked_val = EVBUFFER_CB_ENABLED;
466 } else if (buffer->deferred_cbs) {
467 mask = EVBUFFER_CB_NODEFER|EVBUFFER_CB_ENABLED;
468 masked_val = EVBUFFER_CB_NODEFER|EVBUFFER_CB_ENABLED;
469 /* Don't zero-out n_add/n_del, since the deferred callbacks
470 will want to see them. */
473 mask = EVBUFFER_CB_ENABLED;
474 masked_val = EVBUFFER_CB_ENABLED;
477 ASSERT_EVBUFFER_LOCKED(buffer);
479 if (LIST_EMPTY(&buffer->callbacks)) {
480 buffer->n_add_for_cb = buffer->n_del_for_cb = 0;
483 if (buffer->n_add_for_cb == 0 && buffer->n_del_for_cb == 0)
486 new_size = buffer->total_len;
487 info.orig_size = new_size + buffer->n_del_for_cb - buffer->n_add_for_cb;
488 info.n_added = buffer->n_add_for_cb;
489 info.n_deleted = buffer->n_del_for_cb;
491 buffer->n_add_for_cb = 0;
492 buffer->n_del_for_cb = 0;
494 for (cbent = LIST_FIRST(&buffer->callbacks);
495 cbent != LIST_END(&buffer->callbacks);
497 /* Get the 'next' pointer now in case this callback decides
498 * to remove itself or something. */
499 next = LIST_NEXT(cbent, next);
501 if ((cbent->flags & mask) != masked_val)
504 if ((cbent->flags & EVBUFFER_CB_OBSOLETE))
505 cbent->cb.cb_obsolete(buffer,
506 info.orig_size, new_size, cbent->cbarg);
508 cbent->cb.cb_func(buffer, &info, cbent->cbarg);
513 evbuffer_invoke_callbacks_(struct evbuffer *buffer)
515 if (LIST_EMPTY(&buffer->callbacks)) {
516 buffer->n_add_for_cb = buffer->n_del_for_cb = 0;
520 if (buffer->deferred_cbs) {
521 if (event_deferred_cb_schedule_(buffer->cb_queue, &buffer->deferred)) {
522 evbuffer_incref_and_lock_(buffer);
524 bufferevent_incref_(buffer->parent);
526 EVBUFFER_UNLOCK(buffer);
529 evbuffer_run_callbacks(buffer, 0);
533 evbuffer_deferred_callback(struct event_callback *cb, void *arg)
535 struct bufferevent *parent = NULL;
536 struct evbuffer *buffer = arg;
538 /* XXXX It would be better to run these callbacks without holding the
540 EVBUFFER_LOCK(buffer);
541 parent = buffer->parent;
542 evbuffer_run_callbacks(buffer, 1);
543 evbuffer_decref_and_unlock_(buffer);
545 bufferevent_decref_(parent);
549 evbuffer_remove_all_callbacks(struct evbuffer *buffer)
551 struct evbuffer_cb_entry *cbent;
553 while ((cbent = LIST_FIRST(&buffer->callbacks))) {
554 LIST_REMOVE(cbent, next);
560 evbuffer_decref_and_unlock_(struct evbuffer *buffer)
562 struct evbuffer_chain *chain, *next;
563 ASSERT_EVBUFFER_LOCKED(buffer);
565 EVUTIL_ASSERT(buffer->refcnt > 0);
567 if (--buffer->refcnt > 0) {
568 EVBUFFER_UNLOCK(buffer);
572 for (chain = buffer->first; chain != NULL; chain = next) {
574 evbuffer_chain_free(chain);
576 evbuffer_remove_all_callbacks(buffer);
577 if (buffer->deferred_cbs)
578 event_deferred_cb_cancel_(buffer->cb_queue, &buffer->deferred);
580 EVBUFFER_UNLOCK(buffer);
581 if (buffer->own_lock)
582 EVTHREAD_FREE_LOCK(buffer->lock, EVTHREAD_LOCKTYPE_RECURSIVE);
587 evbuffer_free(struct evbuffer *buffer)
589 EVBUFFER_LOCK(buffer);
590 evbuffer_decref_and_unlock_(buffer);
594 evbuffer_lock(struct evbuffer *buf)
600 evbuffer_unlock(struct evbuffer *buf)
602 EVBUFFER_UNLOCK(buf);
606 evbuffer_get_length(const struct evbuffer *buffer)
610 EVBUFFER_LOCK(buffer);
612 result = (buffer->total_len);
614 EVBUFFER_UNLOCK(buffer);
620 evbuffer_get_contiguous_space(const struct evbuffer *buf)
622 struct evbuffer_chain *chain;
627 result = (chain != NULL ? chain->off : 0);
628 EVBUFFER_UNLOCK(buf);
634 evbuffer_add_iovec(struct evbuffer * buf, struct evbuffer_iovec * vec, int n_vec) {
643 for (n = 0; n < n_vec; n++) {
644 to_alloc += vec[n].iov_len;
647 if (evbuffer_expand_fast_(buf, to_alloc, 2) < 0) {
651 for (n = 0; n < n_vec; n++) {
652 /* XXX each 'add' call here does a bunch of setup that's
653 * obviated by evbuffer_expand_fast_, and some cleanup that we
654 * would like to do only once. Instead we should just extract
655 * the part of the code that's needed. */
657 if (evbuffer_add(buf, vec[n].iov_base, vec[n].iov_len) < 0) {
661 res += vec[n].iov_len;
665 EVBUFFER_UNLOCK(buf);
670 evbuffer_reserve_space(struct evbuffer *buf, ev_ssize_t size,
671 struct evbuffer_iovec *vec, int n_vecs)
673 struct evbuffer_chain *chain, **chainp;
682 if ((chain = evbuffer_expand_singlechain(buf, size)) == NULL)
685 vec[0].iov_base = (void *)CHAIN_SPACE_PTR(chain);
686 vec[0].iov_len = (size_t)CHAIN_SPACE_LEN(chain);
687 EVUTIL_ASSERT(size<0 || (size_t)vec[0].iov_len >= (size_t)size);
690 if (evbuffer_expand_fast_(buf, size, n_vecs)<0)
692 n = evbuffer_read_setup_vecs_(buf, size, vec, n_vecs,
697 EVBUFFER_UNLOCK(buf);
703 advance_last_with_data(struct evbuffer *buf)
706 ASSERT_EVBUFFER_LOCKED(buf);
708 if (!*buf->last_with_datap)
711 while ((*buf->last_with_datap)->next && (*buf->last_with_datap)->next->off) {
712 buf->last_with_datap = &(*buf->last_with_datap)->next;
719 evbuffer_commit_space(struct evbuffer *buf,
720 struct evbuffer_iovec *vec, int n_vecs)
722 struct evbuffer_chain *chain, **firstchainp, **chainp;
734 } else if (n_vecs == 1 &&
735 (buf->last && vec[0].iov_base == (void *)CHAIN_SPACE_PTR(buf->last))) {
736 /* The user only got or used one chain; it might not
737 * be the first one with space in it. */
738 if ((size_t)vec[0].iov_len > (size_t)CHAIN_SPACE_LEN(buf->last))
740 buf->last->off += vec[0].iov_len;
741 added = vec[0].iov_len;
743 advance_last_with_data(buf);
747 /* Advance 'firstchain' to the first chain with space in it. */
748 firstchainp = buf->last_with_datap;
751 if (CHAIN_SPACE_LEN(*firstchainp) == 0) {
752 firstchainp = &(*firstchainp)->next;
755 chain = *firstchainp;
756 /* pass 1: make sure that the pointers and lengths of vecs[] are in
757 * bounds before we try to commit anything. */
758 for (i=0; i<n_vecs; ++i) {
761 if (vec[i].iov_base != (void *)CHAIN_SPACE_PTR(chain) ||
762 (size_t)vec[i].iov_len > CHAIN_SPACE_LEN(chain))
766 /* pass 2: actually adjust all the chains. */
767 chainp = firstchainp;
768 for (i=0; i<n_vecs; ++i) {
769 (*chainp)->off += vec[i].iov_len;
770 added += vec[i].iov_len;
771 if (vec[i].iov_len) {
772 buf->last_with_datap = chainp;
774 chainp = &(*chainp)->next;
778 buf->total_len += added;
779 buf->n_add_for_cb += added;
781 evbuffer_invoke_callbacks_(buf);
784 EVBUFFER_UNLOCK(buf);
789 HAS_PINNED_R(struct evbuffer *buf)
791 return (buf->last && CHAIN_PINNED_R(buf->last));
795 ZERO_CHAIN(struct evbuffer *dst)
797 ASSERT_EVBUFFER_LOCKED(dst);
800 dst->last_with_datap = &(dst)->first;
804 /* Prepares the contents of src to be moved to another buffer by removing
805 * read-pinned chains. The first pinned chain is saved in first, and the
806 * last in last. If src has no read-pinned chains, first and last are set
809 PRESERVE_PINNED(struct evbuffer *src, struct evbuffer_chain **first,
810 struct evbuffer_chain **last)
812 struct evbuffer_chain *chain, **pinned;
814 ASSERT_EVBUFFER_LOCKED(src);
816 if (!HAS_PINNED_R(src)) {
817 *first = *last = NULL;
821 pinned = src->last_with_datap;
822 if (!CHAIN_PINNED_R(*pinned))
823 pinned = &(*pinned)->next;
824 EVUTIL_ASSERT(CHAIN_PINNED_R(*pinned));
825 chain = *first = *pinned;
828 /* If there's data in the first pinned chain, we need to allocate
829 * a new chain and copy the data over. */
831 struct evbuffer_chain *tmp;
833 EVUTIL_ASSERT(pinned == src->last_with_datap);
834 tmp = evbuffer_chain_new(chain->off);
837 memcpy(tmp->buffer, chain->buffer + chain->misalign,
839 tmp->off = chain->off;
840 *src->last_with_datap = tmp;
842 chain->misalign += chain->off;
845 src->last = *src->last_with_datap;
853 RESTORE_PINNED(struct evbuffer *src, struct evbuffer_chain *pinned,
854 struct evbuffer_chain *last)
856 ASSERT_EVBUFFER_LOCKED(src);
865 src->last_with_datap = &src->first;
870 COPY_CHAIN(struct evbuffer *dst, struct evbuffer *src)
872 ASSERT_EVBUFFER_LOCKED(dst);
873 ASSERT_EVBUFFER_LOCKED(src);
874 dst->first = src->first;
875 if (src->last_with_datap == &src->first)
876 dst->last_with_datap = &dst->first;
878 dst->last_with_datap = src->last_with_datap;
879 dst->last = src->last;
880 dst->total_len = src->total_len;
884 APPEND_CHAIN(struct evbuffer *dst, struct evbuffer *src)
886 struct evbuffer_chain **chp;
888 ASSERT_EVBUFFER_LOCKED(dst);
889 ASSERT_EVBUFFER_LOCKED(src);
891 chp = evbuffer_free_trailing_empty_chains(dst);
894 if (src->last_with_datap == &src->first)
895 dst->last_with_datap = chp;
897 dst->last_with_datap = src->last_with_datap;
898 dst->last = src->last;
899 dst->total_len += src->total_len;
903 APPEND_CHAIN_MULTICAST(struct evbuffer *dst, struct evbuffer *src)
905 struct evbuffer_chain *tmp;
906 struct evbuffer_chain *chain = src->first;
907 struct evbuffer_multicast_parent *extra;
909 ASSERT_EVBUFFER_LOCKED(dst);
910 ASSERT_EVBUFFER_LOCKED(src);
912 for (; chain; chain = chain->next) {
913 if (!chain->off || chain->flags & EVBUFFER_DANGLING) {
914 /* skip empty chains */
918 tmp = evbuffer_chain_new(sizeof(struct evbuffer_multicast_parent));
920 event_warn("%s: out of memory", __func__);
923 extra = EVBUFFER_CHAIN_EXTRA(struct evbuffer_multicast_parent, tmp);
924 /* reference evbuffer containing source chain so it
925 * doesn't get released while the chain is still
926 * being referenced to */
927 evbuffer_incref_(src);
929 /* reference source chain which now becomes immutable */
930 evbuffer_chain_incref(chain);
931 extra->parent = chain;
932 chain->flags |= EVBUFFER_IMMUTABLE;
933 tmp->buffer_len = chain->buffer_len;
934 tmp->misalign = chain->misalign;
935 tmp->off = chain->off;
936 tmp->flags |= EVBUFFER_MULTICAST|EVBUFFER_IMMUTABLE;
937 tmp->buffer = chain->buffer;
938 evbuffer_chain_insert(dst, tmp);
943 PREPEND_CHAIN(struct evbuffer *dst, struct evbuffer *src)
945 ASSERT_EVBUFFER_LOCKED(dst);
946 ASSERT_EVBUFFER_LOCKED(src);
947 src->last->next = dst->first;
948 dst->first = src->first;
949 dst->total_len += src->total_len;
950 if (*dst->last_with_datap == NULL) {
951 if (src->last_with_datap == &(src)->first)
952 dst->last_with_datap = &dst->first;
954 dst->last_with_datap = src->last_with_datap;
955 } else if (dst->last_with_datap == &dst->first) {
956 dst->last_with_datap = &src->last->next;
961 evbuffer_add_buffer(struct evbuffer *outbuf, struct evbuffer *inbuf)
963 struct evbuffer_chain *pinned, *last;
964 size_t in_total_len, out_total_len;
967 EVBUFFER_LOCK2(inbuf, outbuf);
968 in_total_len = inbuf->total_len;
969 out_total_len = outbuf->total_len;
971 if (in_total_len == 0 || outbuf == inbuf)
974 if (outbuf->freeze_end || inbuf->freeze_start) {
979 if (PRESERVE_PINNED(inbuf, &pinned, &last) < 0) {
984 if (out_total_len == 0) {
985 /* There might be an empty chain at the start of outbuf; free
987 evbuffer_free_all_chains(outbuf->first);
988 COPY_CHAIN(outbuf, inbuf);
990 APPEND_CHAIN(outbuf, inbuf);
993 RESTORE_PINNED(inbuf, pinned, last);
995 inbuf->n_del_for_cb += in_total_len;
996 outbuf->n_add_for_cb += in_total_len;
998 evbuffer_invoke_callbacks_(inbuf);
999 evbuffer_invoke_callbacks_(outbuf);
1002 EVBUFFER_UNLOCK2(inbuf, outbuf);
1007 evbuffer_add_buffer_reference(struct evbuffer *outbuf, struct evbuffer *inbuf)
1009 size_t in_total_len, out_total_len;
1010 struct evbuffer_chain *chain;
1013 EVBUFFER_LOCK2(inbuf, outbuf);
1014 in_total_len = inbuf->total_len;
1015 out_total_len = outbuf->total_len;
1016 chain = inbuf->first;
1018 if (in_total_len == 0)
1021 if (outbuf->freeze_end || outbuf == inbuf) {
1026 for (; chain; chain = chain->next) {
1027 if ((chain->flags & (EVBUFFER_FILESEGMENT|EVBUFFER_SENDFILE|EVBUFFER_MULTICAST)) != 0) {
1028 /* chain type can not be referenced */
1034 if (out_total_len == 0) {
1035 /* There might be an empty chain at the start of outbuf; free
1037 evbuffer_free_all_chains(outbuf->first);
1039 APPEND_CHAIN_MULTICAST(outbuf, inbuf);
1041 outbuf->n_add_for_cb += in_total_len;
1042 evbuffer_invoke_callbacks_(outbuf);
1045 EVBUFFER_UNLOCK2(inbuf, outbuf);
1050 evbuffer_prepend_buffer(struct evbuffer *outbuf, struct evbuffer *inbuf)
1052 struct evbuffer_chain *pinned, *last;
1053 size_t in_total_len, out_total_len;
1056 EVBUFFER_LOCK2(inbuf, outbuf);
1058 in_total_len = inbuf->total_len;
1059 out_total_len = outbuf->total_len;
1061 if (!in_total_len || inbuf == outbuf)
1064 if (outbuf->freeze_start || inbuf->freeze_start) {
1069 if (PRESERVE_PINNED(inbuf, &pinned, &last) < 0) {
1074 if (out_total_len == 0) {
1075 /* There might be an empty chain at the start of outbuf; free
1077 evbuffer_free_all_chains(outbuf->first);
1078 COPY_CHAIN(outbuf, inbuf);
1080 PREPEND_CHAIN(outbuf, inbuf);
1083 RESTORE_PINNED(inbuf, pinned, last);
1085 inbuf->n_del_for_cb += in_total_len;
1086 outbuf->n_add_for_cb += in_total_len;
1088 evbuffer_invoke_callbacks_(inbuf);
1089 evbuffer_invoke_callbacks_(outbuf);
1091 EVBUFFER_UNLOCK2(inbuf, outbuf);
1096 evbuffer_drain(struct evbuffer *buf, size_t len)
1098 struct evbuffer_chain *chain, *next;
1099 size_t remaining, old_len;
1103 old_len = buf->total_len;
1108 if (buf->freeze_start) {
1113 if (len >= old_len && !HAS_PINNED_R(buf)) {
1115 for (chain = buf->first; chain != NULL; chain = next) {
1117 evbuffer_chain_free(chain);
1125 buf->total_len -= len;
1127 for (chain = buf->first;
1128 remaining >= chain->off;
1131 remaining -= chain->off;
1133 if (chain == *buf->last_with_datap) {
1134 buf->last_with_datap = &buf->first;
1136 if (&chain->next == buf->last_with_datap)
1137 buf->last_with_datap = &buf->first;
1139 if (CHAIN_PINNED_R(chain)) {
1140 EVUTIL_ASSERT(remaining == 0);
1141 chain->misalign += chain->off;
1145 evbuffer_chain_free(chain);
1149 EVUTIL_ASSERT(chain && remaining <= chain->off);
1150 chain->misalign += remaining;
1151 chain->off -= remaining;
1154 buf->n_del_for_cb += len;
1155 /* Tell someone about changes in this buffer */
1156 evbuffer_invoke_callbacks_(buf);
1159 EVBUFFER_UNLOCK(buf);
1163 /* Reads data from an event buffer and drains the bytes read */
1165 evbuffer_remove(struct evbuffer *buf, void *data_out, size_t datlen)
1169 n = evbuffer_copyout_from(buf, NULL, data_out, datlen);
1171 if (evbuffer_drain(buf, n)<0)
1174 EVBUFFER_UNLOCK(buf);
1179 evbuffer_copyout(struct evbuffer *buf, void *data_out, size_t datlen)
1181 return evbuffer_copyout_from(buf, NULL, data_out, datlen);
1185 evbuffer_copyout_from(struct evbuffer *buf, const struct evbuffer_ptr *pos,
1186 void *data_out, size_t datlen)
1188 /*XXX fails badly on sendfile case. */
1189 struct evbuffer_chain *chain;
1190 char *data = data_out;
1192 ev_ssize_t result = 0;
1193 size_t pos_in_chain;
1198 if (datlen > (size_t)(EV_SSIZE_MAX - pos->pos)) {
1202 chain = pos->internal_.chain;
1203 pos_in_chain = pos->internal_.pos_in_chain;
1204 if (datlen + pos->pos > buf->total_len)
1205 datlen = buf->total_len - pos->pos;
1209 if (datlen > buf->total_len)
1210 datlen = buf->total_len;
1217 if (buf->freeze_start) {
1224 while (datlen && datlen >= chain->off - pos_in_chain) {
1225 size_t copylen = chain->off - pos_in_chain;
1227 chain->buffer + chain->misalign + pos_in_chain,
1232 chain = chain->next;
1234 EVUTIL_ASSERT(chain || datlen==0);
1238 EVUTIL_ASSERT(chain);
1239 EVUTIL_ASSERT(datlen+pos_in_chain <= chain->off);
1241 memcpy(data, chain->buffer + chain->misalign + pos_in_chain,
1247 EVBUFFER_UNLOCK(buf);
1251 /* reads data from the src buffer to the dst buffer, avoids memcpy as
1253 /* XXXX should return ev_ssize_t */
1255 evbuffer_remove_buffer(struct evbuffer *src, struct evbuffer *dst,
1258 /*XXX We should have an option to force this to be zero-copy.*/
1260 /*XXX can fail badly on sendfile case. */
1261 struct evbuffer_chain *chain, *previous;
1265 EVBUFFER_LOCK2(src, dst);
1267 chain = previous = src->first;
1269 if (datlen == 0 || dst == src) {
1274 if (dst->freeze_end || src->freeze_start) {
1279 /* short-cut if there is no more data buffered */
1280 if (datlen >= src->total_len) {
1281 datlen = src->total_len;
1282 evbuffer_add_buffer(dst, src);
1283 result = (int)datlen; /*XXXX should return ev_ssize_t*/
1287 /* removes chains if possible */
1288 while (chain->off <= datlen) {
1289 /* We can't remove the last with data from src unless we
1290 * remove all chains, in which case we would have done the if
1292 EVUTIL_ASSERT(chain != *src->last_with_datap);
1293 nread += chain->off;
1294 datlen -= chain->off;
1296 if (src->last_with_datap == &chain->next)
1297 src->last_with_datap = &src->first;
1298 chain = chain->next;
1302 /* we can remove the chain */
1303 struct evbuffer_chain **chp;
1304 chp = evbuffer_free_trailing_empty_chains(dst);
1306 if (dst->first == NULL) {
1307 dst->first = src->first;
1311 dst->last = previous;
1312 previous->next = NULL;
1314 advance_last_with_data(dst);
1316 dst->total_len += nread;
1317 dst->n_add_for_cb += nread;
1320 /* we know that there is more data in the src buffer than
1321 * we want to read, so we manually drain the chain */
1322 evbuffer_add(dst, chain->buffer + chain->misalign, datlen);
1323 chain->misalign += datlen;
1324 chain->off -= datlen;
1327 /* You might think we would want to increment dst->n_add_for_cb
1328 * here too. But evbuffer_add above already took care of that.
1330 src->total_len -= nread;
1331 src->n_del_for_cb += nread;
1334 evbuffer_invoke_callbacks_(dst);
1335 evbuffer_invoke_callbacks_(src);
1337 result = (int)nread;/*XXXX should change return type */
1340 EVBUFFER_UNLOCK2(src, dst);
1345 evbuffer_pullup(struct evbuffer *buf, ev_ssize_t size)
1347 struct evbuffer_chain *chain, *next, *tmp, *last_with_data;
1348 unsigned char *buffer, *result = NULL;
1349 ev_ssize_t remaining;
1350 int removed_last_with_data = 0;
1351 int removed_last_with_datap = 0;
1358 size = buf->total_len;
1359 /* if size > buf->total_len, we cannot guarantee to the user that she
1360 * is going to have a long enough buffer afterwards; so we return
1362 if (size == 0 || (size_t)size > buf->total_len)
1365 /* No need to pull up anything; the first size bytes are
1367 if (chain->off >= (size_t)size) {
1368 result = chain->buffer + chain->misalign;
1372 /* Make sure that none of the chains we need to copy from is pinned. */
1373 remaining = size - chain->off;
1374 EVUTIL_ASSERT(remaining >= 0);
1375 for (tmp=chain->next; tmp; tmp=tmp->next) {
1376 if (CHAIN_PINNED(tmp))
1378 if (tmp->off >= (size_t)remaining)
1380 remaining -= tmp->off;
1383 if (CHAIN_PINNED(chain)) {
1384 size_t old_off = chain->off;
1385 if (CHAIN_SPACE_LEN(chain) < size - chain->off) {
1386 /* not enough room at end of chunk. */
1389 buffer = CHAIN_SPACE_PTR(chain);
1393 chain = chain->next;
1394 } else if (chain->buffer_len - chain->misalign >= (size_t)size) {
1395 /* already have enough space in the first chain */
1396 size_t old_off = chain->off;
1397 buffer = chain->buffer + chain->misalign + chain->off;
1401 chain = chain->next;
1403 if ((tmp = evbuffer_chain_new(size)) == NULL) {
1404 event_warn("%s: out of memory", __func__);
1407 buffer = tmp->buffer;
1412 /* TODO(niels): deal with buffers that point to NULL like sendfile */
1414 /* Copy and free every chunk that will be entirely pulled into tmp */
1415 last_with_data = *buf->last_with_datap;
1416 for (; chain != NULL && (size_t)size >= chain->off; chain = next) {
1419 memcpy(buffer, chain->buffer + chain->misalign, chain->off);
1421 buffer += chain->off;
1422 if (chain == last_with_data)
1423 removed_last_with_data = 1;
1424 if (&chain->next == buf->last_with_datap)
1425 removed_last_with_datap = 1;
1427 evbuffer_chain_free(chain);
1430 if (chain != NULL) {
1431 memcpy(buffer, chain->buffer + chain->misalign, size);
1432 chain->misalign += size;
1440 if (removed_last_with_data) {
1441 buf->last_with_datap = &buf->first;
1442 } else if (removed_last_with_datap) {
1443 if (buf->first->next && buf->first->next->off)
1444 buf->last_with_datap = &buf->first->next;
1446 buf->last_with_datap = &buf->first;
1449 result = (tmp->buffer + tmp->misalign);
1452 EVBUFFER_UNLOCK(buf);
1457 * Reads a line terminated by either '\r\n', '\n\r' or '\r' or '\n'.
1458 * The returned buffer needs to be freed by the called.
1461 evbuffer_readline(struct evbuffer *buffer)
1463 return evbuffer_readln(buffer, NULL, EVBUFFER_EOL_ANY);
1466 static inline ev_ssize_t
1467 evbuffer_strchr(struct evbuffer_ptr *it, const char chr)
1469 struct evbuffer_chain *chain = it->internal_.chain;
1470 size_t i = it->internal_.pos_in_chain;
1471 while (chain != NULL) {
1472 char *buffer = (char *)chain->buffer + chain->misalign;
1473 char *cp = memchr(buffer+i, chr, chain->off-i);
1475 it->internal_.chain = chain;
1476 it->internal_.pos_in_chain = cp - buffer;
1477 it->pos += (cp - buffer - i);
1480 it->pos += chain->off - i;
1482 chain = chain->next;
1488 static inline char *
1489 find_eol_char(char *s, size_t len)
1491 #define CHUNK_SZ 128
1492 /* Lots of benchmarking found this approach to be faster in practice
1493 * than doing two memchrs over the whole buffer, doin a memchr on each
1494 * char of the buffer, or trying to emulate memchr by hand. */
1495 char *s_end, *cr, *lf;
1498 size_t chunk = (s + CHUNK_SZ < s_end) ? CHUNK_SZ : (s_end - s);
1499 cr = memchr(s, '\r', chunk);
1500 lf = memchr(s, '\n', chunk);
1516 evbuffer_find_eol_char(struct evbuffer_ptr *it)
1518 struct evbuffer_chain *chain = it->internal_.chain;
1519 size_t i = it->internal_.pos_in_chain;
1520 while (chain != NULL) {
1521 char *buffer = (char *)chain->buffer + chain->misalign;
1522 char *cp = find_eol_char(buffer+i, chain->off-i);
1524 it->internal_.chain = chain;
1525 it->internal_.pos_in_chain = cp - buffer;
1526 it->pos += (cp - buffer) - i;
1529 it->pos += chain->off - i;
1531 chain = chain->next;
1539 struct evbuffer_ptr *ptr, const char *chrset)
1542 struct evbuffer_chain *chain = ptr->internal_.chain;
1543 size_t i = ptr->internal_.pos_in_chain;
1549 char *buffer = (char *)chain->buffer + chain->misalign;
1550 for (; i < chain->off; ++i) {
1551 const char *p = chrset;
1553 if (buffer[i] == *p++)
1556 ptr->internal_.chain = chain;
1557 ptr->internal_.pos_in_chain = i;
1565 if (! chain->next) {
1566 ptr->internal_.chain = chain;
1567 ptr->internal_.pos_in_chain = i;
1572 chain = chain->next;
1578 evbuffer_getchr(struct evbuffer_ptr *it)
1580 struct evbuffer_chain *chain = it->internal_.chain;
1581 size_t off = it->internal_.pos_in_chain;
1586 return (unsigned char)chain->buffer[chain->misalign + off];
1590 evbuffer_search_eol(struct evbuffer *buffer,
1591 struct evbuffer_ptr *start, size_t *eol_len_out,
1592 enum evbuffer_eol_style eol_style)
1594 struct evbuffer_ptr it, it2;
1595 size_t extra_drain = 0;
1598 /* Avoid locking in trivial edge cases */
1599 if (start && start->internal_.chain == NULL) {
1602 *eol_len_out = extra_drain;
1606 EVBUFFER_LOCK(buffer);
1609 memcpy(&it, start, sizeof(it));
1612 it.internal_.chain = buffer->first;
1613 it.internal_.pos_in_chain = 0;
1616 /* the eol_style determines our first stop character and how many
1617 * characters we are going to drain afterwards. */
1618 switch (eol_style) {
1619 case EVBUFFER_EOL_ANY:
1620 if (evbuffer_find_eol_char(&it) < 0)
1622 memcpy(&it2, &it, sizeof(it));
1623 extra_drain = evbuffer_strspn(&it2, "\r\n");
1625 case EVBUFFER_EOL_CRLF_STRICT: {
1626 it = evbuffer_search(buffer, "\r\n", 2, &it);
1632 case EVBUFFER_EOL_CRLF: {
1633 ev_ssize_t start_pos = it.pos;
1634 /* Look for a LF ... */
1635 if (evbuffer_strchr(&it, '\n') < 0)
1638 /* ... optionally preceeded by a CR. */
1639 if (it.pos == start_pos)
1640 break; /* If the first character is \n, don't back up */
1641 /* This potentially does an extra linear walk over the first
1642 * few chains. Probably, that's not too expensive unless you
1643 * have a really pathological setup. */
1644 memcpy(&it2, &it, sizeof(it));
1645 if (evbuffer_ptr_subtract(buffer, &it2, 1)<0)
1647 if (evbuffer_getchr(&it2) == '\r') {
1648 memcpy(&it, &it2, sizeof(it));
1653 case EVBUFFER_EOL_LF:
1654 if (evbuffer_strchr(&it, '\n') < 0)
1658 case EVBUFFER_EOL_NUL:
1659 if (evbuffer_strchr(&it, '\0') < 0)
1669 EVBUFFER_UNLOCK(buffer);
1674 *eol_len_out = extra_drain;
1680 evbuffer_readln(struct evbuffer *buffer, size_t *n_read_out,
1681 enum evbuffer_eol_style eol_style)
1683 struct evbuffer_ptr it;
1685 size_t n_to_copy=0, extra_drain=0;
1686 char *result = NULL;
1688 EVBUFFER_LOCK(buffer);
1690 if (buffer->freeze_start) {
1694 it = evbuffer_search_eol(buffer, NULL, &extra_drain, eol_style);
1699 if ((line = mm_malloc(n_to_copy+1)) == NULL) {
1700 event_warn("%s: out of memory", __func__);
1704 evbuffer_remove(buffer, line, n_to_copy);
1705 line[n_to_copy] = '\0';
1707 evbuffer_drain(buffer, extra_drain);
1710 EVBUFFER_UNLOCK(buffer);
1713 *n_read_out = result ? n_to_copy : 0;
1718 #define EVBUFFER_CHAIN_MAX_AUTO_SIZE 4096
1720 /* Adds data to an event buffer */
1723 evbuffer_add(struct evbuffer *buf, const void *data_in, size_t datlen)
1725 struct evbuffer_chain *chain, *tmp;
1726 const unsigned char *data = data_in;
1727 size_t remain, to_alloc;
1732 if (buf->freeze_end) {
1735 /* Prevent buf->total_len overflow */
1736 if (datlen > EV_SIZE_MAX - buf->total_len) {
1740 if (*buf->last_with_datap == NULL) {
1743 chain = *buf->last_with_datap;
1746 /* If there are no chains allocated for this buffer, allocate one
1747 * big enough to hold all the data. */
1748 if (chain == NULL) {
1749 chain = evbuffer_chain_new(datlen);
1752 evbuffer_chain_insert(buf, chain);
1755 if ((chain->flags & EVBUFFER_IMMUTABLE) == 0) {
1756 /* Always true for mutable buffers */
1757 EVUTIL_ASSERT(chain->misalign >= 0 &&
1758 (ev_uint64_t)chain->misalign <= EVBUFFER_CHAIN_MAX);
1759 remain = chain->buffer_len - (size_t)chain->misalign - chain->off;
1760 if (remain >= datlen) {
1761 /* there's enough space to hold all the data in the
1762 * current last chain */
1763 memcpy(chain->buffer + chain->misalign + chain->off,
1765 chain->off += datlen;
1766 buf->total_len += datlen;
1767 buf->n_add_for_cb += datlen;
1769 } else if (!CHAIN_PINNED(chain) &&
1770 evbuffer_chain_should_realign(chain, datlen)) {
1771 /* we can fit the data into the misalignment */
1772 evbuffer_chain_align(chain);
1774 memcpy(chain->buffer + chain->off, data, datlen);
1775 chain->off += datlen;
1776 buf->total_len += datlen;
1777 buf->n_add_for_cb += datlen;
1781 /* we cannot write any data to the last chain */
1785 /* we need to add another chain */
1786 to_alloc = chain->buffer_len;
1787 if (to_alloc <= EVBUFFER_CHAIN_MAX_AUTO_SIZE/2)
1789 if (datlen > to_alloc)
1791 tmp = evbuffer_chain_new(to_alloc);
1796 memcpy(chain->buffer + chain->misalign + chain->off,
1798 chain->off += remain;
1799 buf->total_len += remain;
1800 buf->n_add_for_cb += remain;
1806 memcpy(tmp->buffer, data, datlen);
1808 evbuffer_chain_insert(buf, tmp);
1809 buf->n_add_for_cb += datlen;
1812 evbuffer_invoke_callbacks_(buf);
1815 EVBUFFER_UNLOCK(buf);
1820 evbuffer_prepend(struct evbuffer *buf, const void *data, size_t datlen)
1822 struct evbuffer_chain *chain, *tmp;
1827 if (buf->freeze_start) {
1830 if (datlen > EV_SIZE_MAX - buf->total_len) {
1836 if (chain == NULL) {
1837 chain = evbuffer_chain_new(datlen);
1840 evbuffer_chain_insert(buf, chain);
1843 /* we cannot touch immutable buffers */
1844 if ((chain->flags & EVBUFFER_IMMUTABLE) == 0) {
1845 /* Always true for mutable buffers */
1846 EVUTIL_ASSERT(chain->misalign >= 0 &&
1847 (ev_uint64_t)chain->misalign <= EVBUFFER_CHAIN_MAX);
1849 /* If this chain is empty, we can treat it as
1850 * 'empty at the beginning' rather than 'empty at the end' */
1851 if (chain->off == 0)
1852 chain->misalign = chain->buffer_len;
1854 if ((size_t)chain->misalign >= datlen) {
1855 /* we have enough space to fit everything */
1856 memcpy(chain->buffer + chain->misalign - datlen,
1858 chain->off += datlen;
1859 chain->misalign -= datlen;
1860 buf->total_len += datlen;
1861 buf->n_add_for_cb += datlen;
1863 } else if (chain->misalign) {
1864 /* we can only fit some of the data. */
1865 memcpy(chain->buffer,
1866 (char*)data + datlen - chain->misalign,
1867 (size_t)chain->misalign);
1868 chain->off += (size_t)chain->misalign;
1869 buf->total_len += (size_t)chain->misalign;
1870 buf->n_add_for_cb += (size_t)chain->misalign;
1871 datlen -= (size_t)chain->misalign;
1872 chain->misalign = 0;
1876 /* we need to add another chain */
1877 if ((tmp = evbuffer_chain_new(datlen)) == NULL)
1880 if (buf->last_with_datap == &buf->first)
1881 buf->last_with_datap = &tmp->next;
1886 EVUTIL_ASSERT(datlen <= tmp->buffer_len);
1887 tmp->misalign = tmp->buffer_len - datlen;
1889 memcpy(tmp->buffer + tmp->misalign, data, datlen);
1890 buf->total_len += datlen;
1891 buf->n_add_for_cb += datlen;
1894 evbuffer_invoke_callbacks_(buf);
1897 EVBUFFER_UNLOCK(buf);
1901 /** Helper: realigns the memory in chain->buffer so that misalign is 0. */
1903 evbuffer_chain_align(struct evbuffer_chain *chain)
1905 EVUTIL_ASSERT(!(chain->flags & EVBUFFER_IMMUTABLE));
1906 EVUTIL_ASSERT(!(chain->flags & EVBUFFER_MEM_PINNED_ANY));
1907 memmove(chain->buffer, chain->buffer + chain->misalign, chain->off);
1908 chain->misalign = 0;
1911 #define MAX_TO_COPY_IN_EXPAND 4096
1912 #define MAX_TO_REALIGN_IN_EXPAND 2048
1914 /** Helper: return true iff we should realign chain to fit datalen bytes of
1917 evbuffer_chain_should_realign(struct evbuffer_chain *chain,
1920 return chain->buffer_len - chain->off >= datlen &&
1921 (chain->off < chain->buffer_len / 2) &&
1922 (chain->off <= MAX_TO_REALIGN_IN_EXPAND);
1925 /* Expands the available space in the event buffer to at least datlen, all in
1926 * a single chunk. Return that chunk. */
1927 static struct evbuffer_chain *
1928 evbuffer_expand_singlechain(struct evbuffer *buf, size_t datlen)
1930 struct evbuffer_chain *chain, **chainp;
1931 struct evbuffer_chain *result = NULL;
1932 ASSERT_EVBUFFER_LOCKED(buf);
1934 chainp = buf->last_with_datap;
1936 /* XXX If *chainp is no longer writeable, but has enough space in its
1937 * misalign, this might be a bad idea: we could still use *chainp, not
1938 * (*chainp)->next. */
1939 if (*chainp && CHAIN_SPACE_LEN(*chainp) == 0)
1940 chainp = &(*chainp)->next;
1942 /* 'chain' now points to the first chain with writable space (if any)
1943 * We will either use it, realign it, replace it, or resize it. */
1946 if (chain == NULL ||
1947 (chain->flags & (EVBUFFER_IMMUTABLE|EVBUFFER_MEM_PINNED_ANY))) {
1948 /* We can't use the last_with_data chain at all. Just add a
1949 * new one that's big enough. */
1953 /* If we can fit all the data, then we don't have to do anything */
1954 if (CHAIN_SPACE_LEN(chain) >= datlen) {
1959 /* If the chain is completely empty, just replace it by adding a new
1961 if (chain->off == 0) {
1965 /* If the misalignment plus the remaining space fulfills our data
1966 * needs, we could just force an alignment to happen. Afterwards, we
1967 * have enough space. But only do this if we're saving a lot of space
1968 * and not moving too much data. Otherwise the space savings are
1969 * probably offset by the time lost in copying.
1971 if (evbuffer_chain_should_realign(chain, datlen)) {
1972 evbuffer_chain_align(chain);
1977 /* At this point, we can either resize the last chunk with space in
1978 * it, use the next chunk after it, or If we add a new chunk, we waste
1979 * CHAIN_SPACE_LEN(chain) bytes in the former last chunk. If we
1980 * resize, we have to copy chain->off bytes.
1983 /* Would expanding this chunk be affordable and worthwhile? */
1984 if (CHAIN_SPACE_LEN(chain) < chain->buffer_len / 8 ||
1985 chain->off > MAX_TO_COPY_IN_EXPAND ||
1986 datlen >= (EVBUFFER_CHAIN_MAX - chain->off)) {
1987 /* It's not worth resizing this chain. Can the next one be
1989 if (chain->next && CHAIN_SPACE_LEN(chain->next) >= datlen) {
1990 /* Yes, we can just use the next chain (which should
1992 result = chain->next;
1995 /* No; append a new chain (which will free all
1996 * terminal empty chains.) */
2000 /* Okay, we're going to try to resize this chain: Not doing so
2001 * would waste at least 1/8 of its current allocation, and we
2002 * can do so without having to copy more than
2003 * MAX_TO_COPY_IN_EXPAND bytes. */
2004 /* figure out how much space we need */
2005 size_t length = chain->off + datlen;
2006 struct evbuffer_chain *tmp = evbuffer_chain_new(length);
2010 /* copy the data over that we had so far */
2011 tmp->off = chain->off;
2012 memcpy(tmp->buffer, chain->buffer + chain->misalign,
2014 /* fix up the list */
2015 EVUTIL_ASSERT(*chainp == chain);
2016 result = *chainp = tmp;
2018 if (buf->last == chain)
2021 tmp->next = chain->next;
2022 evbuffer_chain_free(chain);
2027 result = evbuffer_chain_insert_new(buf, datlen);
2031 EVUTIL_ASSERT(result);
2032 EVUTIL_ASSERT(CHAIN_SPACE_LEN(result) >= datlen);
2037 /* Make sure that datlen bytes are available for writing in the last n
2038 * chains. Never copies or moves data. */
2040 evbuffer_expand_fast_(struct evbuffer *buf, size_t datlen, int n)
2042 struct evbuffer_chain *chain = buf->last, *tmp, *next;
2046 ASSERT_EVBUFFER_LOCKED(buf);
2047 EVUTIL_ASSERT(n >= 2);
2049 if (chain == NULL || (chain->flags & EVBUFFER_IMMUTABLE)) {
2050 /* There is no last chunk, or we can't touch the last chunk.
2051 * Just add a new chunk. */
2052 chain = evbuffer_chain_new(datlen);
2056 evbuffer_chain_insert(buf, chain);
2060 used = 0; /* number of chains we're using space in. */
2061 avail = 0; /* how much space they have. */
2062 /* How many bytes can we stick at the end of buffer as it is? Iterate
2063 * over the chains at the end of the buffer, tring to see how much
2064 * space we have in the first n. */
2065 for (chain = *buf->last_with_datap; chain; chain = chain->next) {
2067 size_t space = (size_t) CHAIN_SPACE_LEN(chain);
2068 EVUTIL_ASSERT(chain == *buf->last_with_datap);
2074 /* No data in chain; realign it. */
2075 chain->misalign = 0;
2076 avail += chain->buffer_len;
2079 if (avail >= datlen) {
2080 /* There is already enough space. Just return */
2087 /* There wasn't enough space in the first n chains with space in
2088 * them. Either add a new chain with enough space, or replace all
2089 * empty chains with one that has enough space, depending on n. */
2091 /* The loop ran off the end of the chains before it hit n
2092 * chains; we can add another. */
2093 EVUTIL_ASSERT(chain == NULL);
2095 tmp = evbuffer_chain_new(datlen - avail);
2099 buf->last->next = tmp;
2101 /* (we would only set last_with_data if we added the first
2102 * chain. But if the buffer had no chains, we would have
2103 * just allocated a new chain earlier) */
2106 /* Nuke _all_ the empty chains. */
2107 int rmv_all = 0; /* True iff we removed last_with_data. */
2108 chain = *buf->last_with_datap;
2110 EVUTIL_ASSERT(chain == buf->first);
2114 /* can't overflow, since only mutable chains have
2115 * huge misaligns. */
2116 avail = (size_t) CHAIN_SPACE_LEN(chain);
2117 chain = chain->next;
2121 for (; chain; chain = next) {
2123 EVUTIL_ASSERT(chain->off == 0);
2124 evbuffer_chain_free(chain);
2126 EVUTIL_ASSERT(datlen >= avail);
2127 tmp = evbuffer_chain_new(datlen - avail);
2132 buf->last = *buf->last_with_datap;
2133 (*buf->last_with_datap)->next = NULL;
2139 buf->first = buf->last = tmp;
2140 buf->last_with_datap = &buf->first;
2142 (*buf->last_with_datap)->next = tmp;
2150 evbuffer_expand(struct evbuffer *buf, size_t datlen)
2152 struct evbuffer_chain *chain;
2155 chain = evbuffer_expand_singlechain(buf, datlen);
2156 EVBUFFER_UNLOCK(buf);
2157 return chain ? 0 : -1;
2161 * Reads data from a file descriptor into a buffer.
2164 #if defined(EVENT__HAVE_SYS_UIO_H) || defined(_WIN32)
2165 #define USE_IOVEC_IMPL
2168 #ifdef USE_IOVEC_IMPL
2170 #ifdef EVENT__HAVE_SYS_UIO_H
2171 /* number of iovec we use for writev, fragmentation is going to determine
2172 * how much we end up writing */
2174 #define DEFAULT_WRITE_IOVEC 128
2176 #if defined(UIO_MAXIOV) && UIO_MAXIOV < DEFAULT_WRITE_IOVEC
2177 #define NUM_WRITE_IOVEC UIO_MAXIOV
2178 #elif defined(IOV_MAX) && IOV_MAX < DEFAULT_WRITE_IOVEC
2179 #define NUM_WRITE_IOVEC IOV_MAX
2181 #define NUM_WRITE_IOVEC DEFAULT_WRITE_IOVEC
2184 #define IOV_TYPE struct iovec
2185 #define IOV_PTR_FIELD iov_base
2186 #define IOV_LEN_FIELD iov_len
2187 #define IOV_LEN_TYPE size_t
2189 #define NUM_WRITE_IOVEC 16
2190 #define IOV_TYPE WSABUF
2191 #define IOV_PTR_FIELD buf
2192 #define IOV_LEN_FIELD len
2193 #define IOV_LEN_TYPE unsigned long
2196 #define NUM_READ_IOVEC 4
2198 #define EVBUFFER_MAX_READ 4096
2200 /** Helper function to figure out which space to use for reading data into
2201 an evbuffer. Internal use only.
2203 @param buf The buffer to read into
2204 @param howmuch How much we want to read.
2205 @param vecs An array of two or more iovecs or WSABUFs.
2206 @param n_vecs_avail The length of vecs
2207 @param chainp A pointer to a variable to hold the first chain we're
2209 @param exact Boolean: if true, we do not provide more than 'howmuch'
2210 space in the vectors, even if more space is available.
2211 @return The number of buffers we're using.
2214 evbuffer_read_setup_vecs_(struct evbuffer *buf, ev_ssize_t howmuch,
2215 struct evbuffer_iovec *vecs, int n_vecs_avail,
2216 struct evbuffer_chain ***chainp, int exact)
2218 struct evbuffer_chain *chain;
2219 struct evbuffer_chain **firstchainp;
2222 ASSERT_EVBUFFER_LOCKED(buf);
2228 /* Let firstchain be the first chain with any space on it */
2229 firstchainp = buf->last_with_datap;
2230 if (CHAIN_SPACE_LEN(*firstchainp) == 0) {
2231 firstchainp = &(*firstchainp)->next;
2234 chain = *firstchainp;
2235 for (i = 0; i < n_vecs_avail && so_far < (size_t)howmuch; ++i) {
2236 size_t avail = (size_t) CHAIN_SPACE_LEN(chain);
2237 if (avail > (howmuch - so_far) && exact)
2238 avail = howmuch - so_far;
2239 vecs[i].iov_base = (void *)CHAIN_SPACE_PTR(chain);
2240 vecs[i].iov_len = avail;
2242 chain = chain->next;
2245 *chainp = firstchainp;
2250 get_n_bytes_readable_on_socket(evutil_socket_t fd)
2252 #if defined(FIONREAD) && defined(_WIN32)
2253 unsigned long lng = EVBUFFER_MAX_READ;
2254 if (ioctlsocket(fd, FIONREAD, &lng) < 0)
2256 /* Can overflow, but mostly harmlessly. XXXX */
2258 #elif defined(FIONREAD)
2259 int n = EVBUFFER_MAX_READ;
2260 if (ioctl(fd, FIONREAD, &n) < 0)
2264 return EVBUFFER_MAX_READ;
2268 /* TODO(niels): should this function return ev_ssize_t and take ev_ssize_t
2271 evbuffer_read(struct evbuffer *buf, evutil_socket_t fd, int howmuch)
2273 struct evbuffer_chain **chainp;
2277 #ifdef USE_IOVEC_IMPL
2278 int nvecs, i, remaining;
2280 struct evbuffer_chain *chain;
2286 if (buf->freeze_end) {
2291 n = get_n_bytes_readable_on_socket(fd);
2292 if (n <= 0 || n > EVBUFFER_MAX_READ)
2293 n = EVBUFFER_MAX_READ;
2294 if (howmuch < 0 || howmuch > n)
2297 #ifdef USE_IOVEC_IMPL
2298 /* Since we can use iovecs, we're willing to use the last
2299 * NUM_READ_IOVEC chains. */
2300 if (evbuffer_expand_fast_(buf, howmuch, NUM_READ_IOVEC) == -1) {
2304 IOV_TYPE vecs[NUM_READ_IOVEC];
2305 #ifdef EVBUFFER_IOVEC_IS_NATIVE_
2306 nvecs = evbuffer_read_setup_vecs_(buf, howmuch, vecs,
2307 NUM_READ_IOVEC, &chainp, 1);
2309 /* We aren't using the native struct iovec. Therefore,
2311 struct evbuffer_iovec ev_vecs[NUM_READ_IOVEC];
2312 nvecs = evbuffer_read_setup_vecs_(buf, howmuch, ev_vecs, 2,
2315 for (i=0; i < nvecs; ++i)
2316 WSABUF_FROM_EVBUFFER_IOV(&vecs[i], &ev_vecs[i]);
2323 if (WSARecv(fd, vecs, nvecs, &bytesRead, &flags, NULL, NULL)) {
2324 /* The read failed. It might be a close,
2325 * or it might be an error. */
2326 if (WSAGetLastError() == WSAECONNABORTED)
2334 n = readv(fd, vecs, nvecs);
2338 #else /*!USE_IOVEC_IMPL*/
2339 /* If we don't have FIONREAD, we might waste some space here */
2340 /* XXX we _will_ waste some space here if there is any space left
2341 * over on buf->last. */
2342 if ((chain = evbuffer_expand_singlechain(buf, howmuch)) == NULL) {
2347 /* We can append new data at this point */
2348 p = chain->buffer + chain->misalign + chain->off;
2351 n = read(fd, p, howmuch);
2353 n = recv(fd, p, howmuch, 0);
2355 #endif /* USE_IOVEC_IMPL */
2366 #ifdef USE_IOVEC_IMPL
2368 for (i=0; i < nvecs; ++i) {
2369 /* can't overflow, since only mutable chains have
2370 * huge misaligns. */
2371 size_t space = (size_t) CHAIN_SPACE_LEN(*chainp);
2372 /* XXXX This is a kludge that can waste space in perverse
2374 if (space > EVBUFFER_CHAIN_MAX)
2375 space = EVBUFFER_CHAIN_MAX;
2376 if ((ev_ssize_t)space < remaining) {
2377 (*chainp)->off += space;
2378 remaining -= (int)space;
2380 (*chainp)->off += remaining;
2381 buf->last_with_datap = chainp;
2384 chainp = &(*chainp)->next;
2388 advance_last_with_data(buf);
2390 buf->total_len += n;
2391 buf->n_add_for_cb += n;
2393 /* Tell someone about changes in this buffer */
2394 evbuffer_invoke_callbacks_(buf);
2397 EVBUFFER_UNLOCK(buf);
2401 #ifdef USE_IOVEC_IMPL
2403 evbuffer_write_iovec(struct evbuffer *buffer, evutil_socket_t fd,
2406 IOV_TYPE iov[NUM_WRITE_IOVEC];
2407 struct evbuffer_chain *chain = buffer->first;
2413 ASSERT_EVBUFFER_LOCKED(buffer);
2414 /* XXX make this top out at some maximal data length? if the
2415 * buffer has (say) 1MB in it, split over 128 chains, there's
2416 * no way it all gets written in one go. */
2417 while (chain != NULL && i < NUM_WRITE_IOVEC && howmuch) {
2419 /* we cannot write the file info via writev */
2420 if (chain->flags & EVBUFFER_SENDFILE)
2423 iov[i].IOV_PTR_FIELD = (void *) (chain->buffer + chain->misalign);
2424 if ((size_t)howmuch >= chain->off) {
2425 /* XXXcould be problematic when windows supports mmap*/
2426 iov[i++].IOV_LEN_FIELD = (IOV_LEN_TYPE)chain->off;
2427 howmuch -= chain->off;
2429 /* XXXcould be problematic when windows supports mmap*/
2430 iov[i++].IOV_LEN_FIELD = (IOV_LEN_TYPE)howmuch;
2433 chain = chain->next;
2441 if (WSASend(fd, iov, i, &bytesSent, 0, NULL, NULL))
2447 n = writev(fd, iov, i);
2455 evbuffer_write_sendfile(struct evbuffer *buffer, evutil_socket_t dest_fd,
2458 struct evbuffer_chain *chain = buffer->first;
2459 struct evbuffer_chain_file_segment *info =
2460 EVBUFFER_CHAIN_EXTRA(struct evbuffer_chain_file_segment,
2462 const int source_fd = info->segment->fd;
2463 #if defined(SENDFILE_IS_MACOSX) || defined(SENDFILE_IS_FREEBSD)
2465 ev_off_t len = chain->off;
2466 #elif defined(SENDFILE_IS_LINUX) || defined(SENDFILE_IS_SOLARIS)
2468 ev_off_t offset = chain->misalign;
2471 ASSERT_EVBUFFER_LOCKED(buffer);
2473 #if defined(SENDFILE_IS_MACOSX)
2474 res = sendfile(source_fd, dest_fd, chain->misalign, &len, NULL, 0);
2475 if (res == -1 && !EVUTIL_ERR_RW_RETRIABLE(errno))
2479 #elif defined(SENDFILE_IS_FREEBSD)
2480 res = sendfile(source_fd, dest_fd, chain->misalign, chain->off, NULL, &len, 0);
2481 if (res == -1 && !EVUTIL_ERR_RW_RETRIABLE(errno))
2485 #elif defined(SENDFILE_IS_LINUX)
2486 /* TODO(niels): implement splice */
2487 res = sendfile(dest_fd, source_fd, &offset, chain->off);
2488 if (res == -1 && EVUTIL_ERR_RW_RETRIABLE(errno)) {
2489 /* if this is EAGAIN or EINTR return 0; otherwise, -1 */
2493 #elif defined(SENDFILE_IS_SOLARIS)
2495 const off_t offset_orig = offset;
2496 res = sendfile(dest_fd, source_fd, &offset, chain->off);
2497 if (res == -1 && EVUTIL_ERR_RW_RETRIABLE(errno)) {
2498 if (offset - offset_orig)
2499 return offset - offset_orig;
2500 /* if this is EAGAIN or EINTR and no bytes were
2501 * written, return 0 */
2511 evbuffer_write_atmost(struct evbuffer *buffer, evutil_socket_t fd,
2516 EVBUFFER_LOCK(buffer);
2518 if (buffer->freeze_start) {
2522 if (howmuch < 0 || (size_t)howmuch > buffer->total_len)
2523 howmuch = buffer->total_len;
2527 struct evbuffer_chain *chain = buffer->first;
2528 if (chain != NULL && (chain->flags & EVBUFFER_SENDFILE))
2529 n = evbuffer_write_sendfile(buffer, fd, howmuch);
2532 #ifdef USE_IOVEC_IMPL
2533 n = evbuffer_write_iovec(buffer, fd, howmuch);
2534 #elif defined(_WIN32)
2535 /* XXX(nickm) Don't disable this code until we know if
2536 * the WSARecv code above works. */
2537 void *p = evbuffer_pullup(buffer, howmuch);
2538 EVUTIL_ASSERT(p || !howmuch);
2539 n = send(fd, p, howmuch, 0);
2541 void *p = evbuffer_pullup(buffer, howmuch);
2542 EVUTIL_ASSERT(p || !howmuch);
2543 n = write(fd, p, howmuch);
2551 evbuffer_drain(buffer, n);
2554 EVBUFFER_UNLOCK(buffer);
2559 evbuffer_write(struct evbuffer *buffer, evutil_socket_t fd)
2561 return evbuffer_write_atmost(buffer, fd, -1);
2565 evbuffer_find(struct evbuffer *buffer, const unsigned char *what, size_t len)
2567 unsigned char *search;
2568 struct evbuffer_ptr ptr;
2570 EVBUFFER_LOCK(buffer);
2572 ptr = evbuffer_search(buffer, (const char *)what, len, NULL);
2576 search = evbuffer_pullup(buffer, ptr.pos + len);
2580 EVBUFFER_UNLOCK(buffer);
2584 /* Subract <b>howfar</b> from the position of <b>pos</b> within
2585 * <b>buf</b>. Returns 0 on success, -1 on failure.
2587 * This isn't exposed yet, because of potential inefficiency issues.
2588 * Maybe it should be. */
2590 evbuffer_ptr_subtract(struct evbuffer *buf, struct evbuffer_ptr *pos,
2595 if (howfar > (size_t)pos->pos)
2597 if (pos->internal_.chain && howfar <= pos->internal_.pos_in_chain) {
2598 pos->internal_.pos_in_chain -= howfar;
2602 const size_t newpos = pos->pos - howfar;
2603 /* Here's the inefficient part: it walks over the
2604 * chains until we hit newpos. */
2605 return evbuffer_ptr_set(buf, pos, newpos, EVBUFFER_PTR_SET);
2610 evbuffer_ptr_set(struct evbuffer *buf, struct evbuffer_ptr *pos,
2611 size_t position, enum evbuffer_ptr_how how)
2613 size_t left = position;
2614 struct evbuffer_chain *chain = NULL;
2620 case EVBUFFER_PTR_SET:
2622 pos->pos = position;
2625 case EVBUFFER_PTR_ADD:
2626 /* this avoids iterating over all previous chains if
2627 we just want to advance the position */
2628 if (pos->pos < 0 || EV_SIZE_MAX - position < (size_t)pos->pos) {
2629 EVBUFFER_UNLOCK(buf);
2632 chain = pos->internal_.chain;
2633 pos->pos += position;
2634 position = pos->internal_.pos_in_chain;
2638 EVUTIL_ASSERT(EV_SIZE_MAX - left >= position);
2639 while (chain && position + left >= chain->off) {
2640 left -= chain->off - position;
2641 chain = chain->next;
2645 pos->internal_.chain = chain;
2646 pos->internal_.pos_in_chain = position + left;
2647 } else if (left == 0) {
2648 /* The first byte in the (nonexistent) chain after the last chain */
2649 pos->internal_.chain = NULL;
2650 pos->internal_.pos_in_chain = 0;
2656 EVBUFFER_UNLOCK(buf);
2662 Compare the bytes in buf at position pos to the len bytes in mem. Return
2663 less than 0, 0, or greater than 0 as memcmp.
2666 evbuffer_ptr_memcmp(const struct evbuffer *buf, const struct evbuffer_ptr *pos,
2667 const char *mem, size_t len)
2669 struct evbuffer_chain *chain;
2673 ASSERT_EVBUFFER_LOCKED(buf);
2676 EV_SIZE_MAX - len < (size_t)pos->pos ||
2677 pos->pos + len > buf->total_len)
2680 chain = pos->internal_.chain;
2681 position = pos->internal_.pos_in_chain;
2682 while (len && chain) {
2683 size_t n_comparable;
2684 if (len + position > chain->off)
2685 n_comparable = chain->off - position;
2688 r = memcmp(chain->buffer + chain->misalign + position, mem,
2692 mem += n_comparable;
2693 len -= n_comparable;
2695 chain = chain->next;
2702 evbuffer_search(struct evbuffer *buffer, const char *what, size_t len, const struct evbuffer_ptr *start)
2704 return evbuffer_search_range(buffer, what, len, start, NULL);
2708 evbuffer_search_range(struct evbuffer *buffer, const char *what, size_t len, const struct evbuffer_ptr *start, const struct evbuffer_ptr *end)
2710 struct evbuffer_ptr pos;
2711 struct evbuffer_chain *chain, *last_chain = NULL;
2712 const unsigned char *p;
2715 EVBUFFER_LOCK(buffer);
2718 memcpy(&pos, start, sizeof(pos));
2719 chain = pos.internal_.chain;
2722 chain = pos.internal_.chain = buffer->first;
2723 pos.internal_.pos_in_chain = 0;
2727 last_chain = end->internal_.chain;
2729 if (!len || len > EV_SSIZE_MAX)
2735 const unsigned char *start_at =
2736 chain->buffer + chain->misalign +
2737 pos.internal_.pos_in_chain;
2738 p = memchr(start_at, first,
2739 chain->off - pos.internal_.pos_in_chain);
2741 pos.pos += p - start_at;
2742 pos.internal_.pos_in_chain += p - start_at;
2743 if (!evbuffer_ptr_memcmp(buffer, &pos, what, len)) {
2744 if (end && pos.pos + (ev_ssize_t)len > end->pos)
2750 ++pos.internal_.pos_in_chain;
2751 if (pos.internal_.pos_in_chain == chain->off) {
2752 chain = pos.internal_.chain = chain->next;
2753 pos.internal_.pos_in_chain = 0;
2756 if (chain == last_chain)
2758 pos.pos += chain->off - pos.internal_.pos_in_chain;
2759 chain = pos.internal_.chain = chain->next;
2760 pos.internal_.pos_in_chain = 0;
2765 PTR_NOT_FOUND(&pos);
2767 EVBUFFER_UNLOCK(buffer);
2772 evbuffer_peek(struct evbuffer *buffer, ev_ssize_t len,
2773 struct evbuffer_ptr *start_at,
2774 struct evbuffer_iovec *vec, int n_vec)
2776 struct evbuffer_chain *chain;
2778 ev_ssize_t len_so_far = 0;
2780 /* Avoid locking in trivial edge cases */
2781 if (start_at && start_at->internal_.chain == NULL)
2784 EVBUFFER_LOCK(buffer);
2787 chain = start_at->internal_.chain;
2788 len_so_far = chain->off
2789 - start_at->internal_.pos_in_chain;
2792 vec[0].iov_base = (void *)(chain->buffer + chain->misalign
2793 + start_at->internal_.pos_in_chain);
2794 vec[0].iov_len = len_so_far;
2796 chain = chain->next;
2798 chain = buffer->first;
2801 if (n_vec == 0 && len < 0) {
2802 /* If no vectors are provided and they asked for "everything",
2803 * pretend they asked for the actual available amount. */
2804 len = buffer->total_len;
2806 len -= start_at->pos;
2811 if (len >= 0 && len_so_far >= len)
2814 vec[idx].iov_base = (void *)(chain->buffer + chain->misalign);
2815 vec[idx].iov_len = chain->off;
2820 len_so_far += chain->off;
2821 chain = chain->next;
2824 EVBUFFER_UNLOCK(buffer);
2831 evbuffer_add_vprintf(struct evbuffer *buf, const char *fmt, va_list ap)
2835 int sz, result = -1;
2837 struct evbuffer_chain *chain;
2842 if (buf->freeze_end) {
2846 /* make sure that at least some space is available */
2847 if ((chain = evbuffer_expand_singlechain(buf, 64)) == NULL)
2852 size_t used = chain->misalign + chain->off;
2853 buffer = (char *)chain->buffer + chain->misalign + chain->off;
2854 EVUTIL_ASSERT(chain->buffer_len >= used);
2855 space = chain->buffer_len - used;
2857 buffer = (char*) CHAIN_SPACE_PTR(chain);
2858 space = (size_t) CHAIN_SPACE_LEN(chain);
2861 #define va_copy(dst, src) memcpy(&(dst), &(src), sizeof(va_list))
2865 sz = evutil_vsnprintf(buffer, space, fmt, aq);
2871 if (INT_MAX >= EVBUFFER_CHAIN_MAX &&
2872 (size_t)sz >= EVBUFFER_CHAIN_MAX)
2874 if ((size_t)sz < space) {
2876 buf->total_len += sz;
2877 buf->n_add_for_cb += sz;
2879 advance_last_with_data(buf);
2880 evbuffer_invoke_callbacks_(buf);
2884 if ((chain = evbuffer_expand_singlechain(buf, sz + 1)) == NULL)
2890 EVBUFFER_UNLOCK(buf);
2895 evbuffer_add_printf(struct evbuffer *buf, const char *fmt, ...)
2901 res = evbuffer_add_vprintf(buf, fmt, ap);
2908 evbuffer_add_reference(struct evbuffer *outbuf,
2909 const void *data, size_t datlen,
2910 evbuffer_ref_cleanup_cb cleanupfn, void *extra)
2912 struct evbuffer_chain *chain;
2913 struct evbuffer_chain_reference *info;
2916 chain = evbuffer_chain_new(sizeof(struct evbuffer_chain_reference));
2919 chain->flags |= EVBUFFER_REFERENCE | EVBUFFER_IMMUTABLE;
2920 chain->buffer = (unsigned char *)data;
2921 chain->buffer_len = datlen;
2922 chain->off = datlen;
2924 info = EVBUFFER_CHAIN_EXTRA(struct evbuffer_chain_reference, chain);
2925 info->cleanupfn = cleanupfn;
2926 info->extra = extra;
2928 EVBUFFER_LOCK(outbuf);
2929 if (outbuf->freeze_end) {
2930 /* don't call chain_free; we do not want to actually invoke
2931 * the cleanup function */
2935 evbuffer_chain_insert(outbuf, chain);
2936 outbuf->n_add_for_cb += datlen;
2938 evbuffer_invoke_callbacks_(outbuf);
2942 EVBUFFER_UNLOCK(outbuf);
2947 /* TODO(niels): we may want to add to automagically convert to mmap, in
2948 * case evbuffer_remove() or evbuffer_pullup() are being used.
2950 struct evbuffer_file_segment *
2951 evbuffer_file_segment_new(
2952 int fd, ev_off_t offset, ev_off_t length, unsigned flags)
2954 struct evbuffer_file_segment *seg =
2955 mm_calloc(sizeof(struct evbuffer_file_segment), 1);
2961 seg->file_offset = offset;
2962 seg->cleanup_cb = NULL;
2963 seg->cleanup_cb_arg = NULL;
2966 #define lseek _lseeki64
2969 #define fstat _fstat
2977 if (fstat(fd, &st) < 0)
2979 length = st.st_size;
2981 seg->length = length;
2983 if (offset < 0 || length < 0 ||
2984 ((ev_uint64_t)length > EVBUFFER_CHAIN_MAX) ||
2985 (ev_uint64_t)offset > (ev_uint64_t)(EVBUFFER_CHAIN_MAX - length))
2988 #if defined(USE_SENDFILE)
2989 if (!(flags & EVBUF_FS_DISABLE_SENDFILE)) {
2990 seg->can_sendfile = 1;
2995 if (evbuffer_file_segment_materialize(seg)<0)
2998 #if defined(USE_SENDFILE)
3001 if (!(flags & EVBUF_FS_DISABLE_LOCKING)) {
3002 EVTHREAD_ALLOC_LOCK(seg->lock, 0);
3010 #ifdef EVENT__HAVE_MMAP
3015 return sysconf(SC_PAGE_SIZE);
3016 #elif defined(_SC_PAGE_SIZE)
3017 return sysconf(_SC_PAGE_SIZE);
3027 evbuffer_file_segment_materialize(struct evbuffer_file_segment *seg)
3029 const unsigned flags = seg->flags;
3030 const int fd = seg->fd;
3031 const ev_off_t length = seg->length;
3032 const ev_off_t offset = seg->file_offset;
3035 return 0; /* already materialized */
3037 #if defined(EVENT__HAVE_MMAP)
3038 if (!(flags & EVBUF_FS_DISABLE_MMAP)) {
3039 off_t offset_rounded = 0, offset_leftover = 0;
3042 /* mmap implementations don't generally like us
3043 * to have an offset that isn't a round */
3044 long page_size = get_page_size();
3045 if (page_size == -1)
3047 offset_leftover = offset % page_size;
3048 offset_rounded = offset - offset_leftover;
3050 mapped = mmap(NULL, length + offset_leftover,
3053 MAP_NOCACHE | /* ??? */
3059 fd, offset_rounded);
3060 if (mapped == MAP_FAILED) {
3061 event_warn("%s: mmap(%d, %d, %zu) failed",
3062 __func__, fd, 0, (size_t)(offset + length));
3064 seg->mapping = mapped;
3065 seg->contents = (char*)mapped+offset_leftover;
3066 seg->mmap_offset = 0;
3067 seg->is_mapping = 1;
3073 if (!(flags & EVBUF_FS_DISABLE_MMAP)) {
3074 intptr_t h = _get_osfhandle(fd);
3076 ev_uint64_t total_size = length+offset;
3077 if ((HANDLE)h == INVALID_HANDLE_VALUE)
3079 m = CreateFileMapping((HANDLE)h, NULL, PAGE_READONLY,
3080 (total_size >> 32), total_size & 0xfffffffful,
3082 if (m != INVALID_HANDLE_VALUE) { /* Does h leak? */
3083 seg->mapping_handle = m;
3084 seg->mmap_offset = offset;
3085 seg->is_mapping = 1;
3091 ev_off_t start_pos = lseek(fd, 0, SEEK_CUR), pos;
3092 ev_off_t read_so_far = 0;
3096 if (!(mem = mm_malloc(length)))
3098 if (start_pos < 0) {
3102 if (lseek(fd, offset, SEEK_SET) < 0) {
3106 while (read_so_far < length) {
3107 n = read(fd, mem+read_so_far, length-read_so_far);
3114 pos = lseek(fd, start_pos, SEEK_SET);
3115 if (n < 0 || (n == 0 && length > read_so_far)) {
3119 } else if (pos < 0) {
3124 seg->contents = mem;
3133 void evbuffer_file_segment_add_cleanup_cb(struct evbuffer_file_segment *seg,
3134 evbuffer_file_segment_cleanup_cb cb, void* arg)
3136 EVUTIL_ASSERT(seg->refcnt > 0);
3137 seg->cleanup_cb = cb;
3138 seg->cleanup_cb_arg = arg;
3142 evbuffer_file_segment_free(struct evbuffer_file_segment *seg)
3145 EVLOCK_LOCK(seg->lock, 0);
3146 refcnt = --seg->refcnt;
3147 EVLOCK_UNLOCK(seg->lock, 0);
3150 EVUTIL_ASSERT(refcnt == 0);
3152 if (seg->is_mapping) {
3154 CloseHandle(seg->mapping_handle);
3155 #elif defined (EVENT__HAVE_MMAP)
3156 off_t offset_leftover;
3157 offset_leftover = seg->file_offset % get_page_size();
3158 if (munmap(seg->mapping, seg->length + offset_leftover) == -1)
3159 event_warn("%s: munmap failed", __func__);
3161 } else if (seg->contents) {
3162 mm_free(seg->contents);
3165 if ((seg->flags & EVBUF_FS_CLOSE_ON_FREE) && seg->fd >= 0) {
3169 if (seg->cleanup_cb) {
3170 (*seg->cleanup_cb)((struct evbuffer_file_segment const*)seg,
3171 seg->flags, seg->cleanup_cb_arg);
3172 seg->cleanup_cb = NULL;
3173 seg->cleanup_cb_arg = NULL;
3176 EVTHREAD_FREE_LOCK(seg->lock, 0);
3181 evbuffer_add_file_segment(struct evbuffer *buf,
3182 struct evbuffer_file_segment *seg, ev_off_t offset, ev_off_t length)
3184 struct evbuffer_chain *chain;
3185 struct evbuffer_chain_file_segment *extra;
3186 int can_use_sendfile = 0;
3189 EVLOCK_LOCK(seg->lock, 0);
3190 if (buf->flags & EVBUFFER_FLAG_DRAINS_TO_FD) {
3191 can_use_sendfile = 1;
3193 if (!seg->contents) {
3194 if (evbuffer_file_segment_materialize(seg)<0) {
3195 EVLOCK_UNLOCK(seg->lock, 0);
3196 EVBUFFER_UNLOCK(buf);
3202 EVLOCK_UNLOCK(seg->lock, 0);
3204 if (buf->freeze_end)
3208 if (offset > seg->length)
3210 length = seg->length - offset;
3213 /* Can we actually add this? */
3214 if (offset+length > seg->length)
3217 chain = evbuffer_chain_new(sizeof(struct evbuffer_chain_file_segment));
3220 extra = EVBUFFER_CHAIN_EXTRA(struct evbuffer_chain_file_segment, chain);
3222 chain->flags |= EVBUFFER_IMMUTABLE|EVBUFFER_FILESEGMENT;
3223 if (can_use_sendfile && seg->can_sendfile) {
3224 chain->flags |= EVBUFFER_SENDFILE;
3225 chain->misalign = seg->file_offset + offset;
3226 chain->off = length;
3227 chain->buffer_len = chain->misalign + length;
3228 } else if (seg->is_mapping) {
3230 ev_uint64_t total_offset = seg->mmap_offset+offset;
3231 ev_uint64_t offset_rounded=0, offset_remaining=0;
3235 memset(&si, 0, sizeof(si)); /* cargo cult */
3237 offset_remaining = total_offset % si.dwAllocationGranularity;
3238 offset_rounded = total_offset - offset_remaining;
3240 data = MapViewOfFile(
3241 seg->mapping_handle,
3243 offset_rounded >> 32,
3244 offset_rounded & 0xfffffffful,
3245 length + offset_remaining);
3250 chain->buffer = (unsigned char*) data;
3251 chain->buffer_len = length+offset_remaining;
3252 chain->misalign = offset_remaining;
3253 chain->off = length;
3255 chain->buffer = (unsigned char*)(seg->contents + offset);
3256 chain->buffer_len = length;
3257 chain->off = length;
3260 chain->buffer = (unsigned char*)(seg->contents + offset);
3261 chain->buffer_len = length;
3262 chain->off = length;
3265 extra->segment = seg;
3266 buf->n_add_for_cb += length;
3267 evbuffer_chain_insert(buf, chain);
3269 evbuffer_invoke_callbacks_(buf);
3271 EVBUFFER_UNLOCK(buf);
3275 EVBUFFER_UNLOCK(buf);
3276 evbuffer_file_segment_free(seg); /* Lowers the refcount */
3281 evbuffer_add_file(struct evbuffer *buf, int fd, ev_off_t offset, ev_off_t length)
3283 struct evbuffer_file_segment *seg;
3284 unsigned flags = EVBUF_FS_CLOSE_ON_FREE;
3287 seg = evbuffer_file_segment_new(fd, offset, length, flags);
3290 r = evbuffer_add_file_segment(buf, seg, 0, length);
3292 evbuffer_file_segment_free(seg);
3297 evbuffer_setcb(struct evbuffer *buffer, evbuffer_cb cb, void *cbarg)
3299 EVBUFFER_LOCK(buffer);
3301 if (!LIST_EMPTY(&buffer->callbacks))
3302 evbuffer_remove_all_callbacks(buffer);
3305 struct evbuffer_cb_entry *ent =
3306 evbuffer_add_cb(buffer, NULL, cbarg);
3307 ent->cb.cb_obsolete = cb;
3308 ent->flags |= EVBUFFER_CB_OBSOLETE;
3310 EVBUFFER_UNLOCK(buffer);
3313 struct evbuffer_cb_entry *
3314 evbuffer_add_cb(struct evbuffer *buffer, evbuffer_cb_func cb, void *cbarg)
3316 struct evbuffer_cb_entry *e;
3317 if (! (e = mm_calloc(1, sizeof(struct evbuffer_cb_entry))))
3319 EVBUFFER_LOCK(buffer);
3322 e->flags = EVBUFFER_CB_ENABLED;
3323 LIST_INSERT_HEAD(&buffer->callbacks, e, next);
3324 EVBUFFER_UNLOCK(buffer);
3329 evbuffer_remove_cb_entry(struct evbuffer *buffer,
3330 struct evbuffer_cb_entry *ent)
3332 EVBUFFER_LOCK(buffer);
3333 LIST_REMOVE(ent, next);
3334 EVBUFFER_UNLOCK(buffer);
3340 evbuffer_remove_cb(struct evbuffer *buffer, evbuffer_cb_func cb, void *cbarg)
3342 struct evbuffer_cb_entry *cbent;
3344 EVBUFFER_LOCK(buffer);
3345 LIST_FOREACH(cbent, &buffer->callbacks, next) {
3346 if (cb == cbent->cb.cb_func && cbarg == cbent->cbarg) {
3347 result = evbuffer_remove_cb_entry(buffer, cbent);
3352 EVBUFFER_UNLOCK(buffer);
3357 evbuffer_cb_set_flags(struct evbuffer *buffer,
3358 struct evbuffer_cb_entry *cb, ev_uint32_t flags)
3360 /* the user isn't allowed to mess with these. */
3361 flags &= ~EVBUFFER_CB_INTERNAL_FLAGS;
3362 EVBUFFER_LOCK(buffer);
3364 EVBUFFER_UNLOCK(buffer);
3369 evbuffer_cb_clear_flags(struct evbuffer *buffer,
3370 struct evbuffer_cb_entry *cb, ev_uint32_t flags)
3372 /* the user isn't allowed to mess with these. */
3373 flags &= ~EVBUFFER_CB_INTERNAL_FLAGS;
3374 EVBUFFER_LOCK(buffer);
3375 cb->flags &= ~flags;
3376 EVBUFFER_UNLOCK(buffer);
3381 evbuffer_freeze(struct evbuffer *buffer, int start)
3383 EVBUFFER_LOCK(buffer);
3385 buffer->freeze_start = 1;
3387 buffer->freeze_end = 1;
3388 EVBUFFER_UNLOCK(buffer);
3393 evbuffer_unfreeze(struct evbuffer *buffer, int start)
3395 EVBUFFER_LOCK(buffer);
3397 buffer->freeze_start = 0;
3399 buffer->freeze_end = 0;
3400 EVBUFFER_UNLOCK(buffer);
3406 evbuffer_cb_suspend(struct evbuffer *buffer, struct evbuffer_cb_entry *cb)
3408 if (!(cb->flags & EVBUFFER_CB_SUSPENDED)) {
3409 cb->size_before_suspend = evbuffer_get_length(buffer);
3410 cb->flags |= EVBUFFER_CB_SUSPENDED;
3415 evbuffer_cb_unsuspend(struct evbuffer *buffer, struct evbuffer_cb_entry *cb)
3417 if ((cb->flags & EVBUFFER_CB_SUSPENDED)) {
3418 unsigned call = (cb->flags & EVBUFFER_CB_CALL_ON_UNSUSPEND);
3419 size_t sz = cb->size_before_suspend;
3420 cb->flags &= ~(EVBUFFER_CB_SUSPENDED|
3421 EVBUFFER_CB_CALL_ON_UNSUSPEND);
3422 cb->size_before_suspend = 0;
3423 if (call && (cb->flags & EVBUFFER_CB_ENABLED)) {
3424 cb->cb(buffer, sz, evbuffer_get_length(buffer), cb->cbarg);
3431 evbuffer_get_callbacks_(struct evbuffer *buffer, struct event_callback **cbs,
3435 EVBUFFER_LOCK(buffer);
3436 if (buffer->deferred_cbs) {
3441 cbs[0] = &buffer->deferred;
3445 EVBUFFER_UNLOCK(buffer);