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18 * @brief APR-UTIL Buckets/Bucket Brigades
24 #if defined(APR_BUCKET_DEBUG) && !defined(APR_RING_DEBUG)
25 #define APR_RING_DEBUG
29 #include "apr_network_io.h"
30 #include "apr_file_io.h"
31 #include "apr_general.h"
33 #include "apr_errno.h"
36 #if APR_HAVE_SYS_UIO_H
37 #include <sys/uio.h> /* for struct iovec */
48 * @defgroup APR_Util_Bucket_Brigades Bucket Brigades
53 /** default bucket buffer size - 8KB minus room for memory allocator headers */
54 #define APR_BUCKET_BUFF_SIZE 8000
56 /** Determines how a bucket or brigade should be read */
58 APR_BLOCK_READ, /**< block until data becomes available */
59 APR_NONBLOCK_READ /**< return immediately if no data is available */
63 * The one-sentence buzzword-laden overview: Bucket brigades represent
64 * a complex data stream that can be passed through a layered IO
65 * system without unnecessary copying. A longer overview follows...
67 * A bucket brigade is a doubly linked list (ring) of buckets, so we
68 * aren't limited to inserting at the front and removing at the end.
69 * Buckets are only passed around as members of a brigade, although
70 * singleton buckets can occur for short periods of time.
72 * Buckets are data stores of various types. They can refer to data in
73 * memory, or part of a file or mmap area, or the output of a process,
74 * etc. Buckets also have some type-dependent accessor functions:
75 * read, split, copy, setaside, and destroy.
77 * read returns the address and size of the data in the bucket. If the
78 * data isn't in memory then it is read in and the bucket changes type
79 * so that it can refer to the new location of the data. If all the
80 * data doesn't fit in the bucket then a new bucket is inserted into
81 * the brigade to hold the rest of it.
83 * split divides the data in a bucket into two regions. After a split
84 * the original bucket refers to the first part of the data and a new
85 * bucket inserted into the brigade after the original bucket refers
86 * to the second part of the data. Reference counts are maintained as
89 * setaside ensures that the data in the bucket has a long enough
90 * lifetime. Sometimes it is convenient to create a bucket referring
91 * to data on the stack in the expectation that it will be consumed
92 * (output to the network) before the stack is unwound. If that
93 * expectation turns out not to be valid, the setaside function is
94 * called to move the data somewhere safer.
96 * copy makes a duplicate of the bucket structure as long as it's
97 * possible to have multiple references to a single copy of the
98 * data itself. Not all bucket types can be copied.
100 * destroy maintains the reference counts on the resources used by a
101 * bucket and frees them if necessary.
103 * Note: all of the above functions have wrapper macros (apr_bucket_read(),
104 * apr_bucket_destroy(), etc), and those macros should be used rather
105 * than using the function pointers directly.
107 * To write a bucket brigade, they are first made into an iovec, so that we
108 * don't write too little data at one time. Currently we ignore compacting the
109 * buckets into as few buckets as possible, but if we really want good
110 * performance, then we need to compact the buckets before we convert to an
111 * iovec, or possibly while we are converting to an iovec.
115 * Forward declaration of the main types.
118 /** @see apr_bucket_brigade */
119 typedef struct apr_bucket_brigade apr_bucket_brigade;
120 /** @see apr_bucket */
121 typedef struct apr_bucket apr_bucket;
122 /** @see apr_bucket_alloc_t */
123 typedef struct apr_bucket_alloc_t apr_bucket_alloc_t;
125 /** @see apr_bucket_type_t */
126 typedef struct apr_bucket_type_t apr_bucket_type_t;
131 struct apr_bucket_type_t {
133 * The name of the bucket type
137 * The number of functions this bucket understands. Can not be less than
142 * Whether the bucket contains metadata (ie, information that
143 * describes the regular contents of the brigade). The metadata
144 * is not returned by apr_bucket_read() and is not indicated by
145 * the ->length of the apr_bucket itself. In other words, an
146 * empty bucket is safe to arbitrarily remove if and only if it
147 * contains no metadata. In this sense, "data" is just raw bytes
148 * that are the "content" of the brigade and "metadata" describes
149 * that data but is not a proper part of it.
152 /** This bucket type represents actual data to send to the client. */
154 /** This bucket type represents metadata. */
155 APR_BUCKET_METADATA = 1
158 * Free the private data and any resources used by the bucket (if they
159 * aren't shared with another bucket). This function is required to be
160 * implemented for all bucket types, though it might be a no-op on some
161 * of them (namely ones that never allocate any private data structures).
162 * @param data The private data pointer from the bucket to be destroyed
164 void (*destroy)(void *data);
167 * Read the data from the bucket. This is required to be implemented
168 * for all bucket types.
169 * @param b The bucket to read from
170 * @param str A place to store the data read. Allocation should only be
171 * done if absolutely necessary.
172 * @param len The amount of data read.
173 * @param block Should this read function block if there is more data that
174 * cannot be read immediately.
176 apr_status_t (*read)(apr_bucket *b, const char **str, apr_size_t *len,
177 apr_read_type_e block);
180 * Make it possible to set aside the data for at least as long as the
181 * given pool. Buckets containing data that could potentially die before
182 * this pool (e.g. the data resides on the stack, in a child pool of
183 * the given pool, or in a disjoint pool) must somehow copy, shift, or
184 * transform the data to have the proper lifetime.
185 * @param e The bucket to convert
186 * @remark Some bucket types contain data that will always outlive the
187 * bucket itself. For example no data (EOS and FLUSH), or the data
188 * resides in global, constant memory (IMMORTAL), or the data is on
189 * the heap (HEAP). For these buckets, apr_bucket_setaside_noop can
192 apr_status_t (*setaside)(apr_bucket *e, apr_pool_t *pool);
195 * Split one bucket in two at the specified position by duplicating
196 * the bucket structure (not the data) and modifying any necessary
197 * start/end/offset information. If it's not possible to do this
198 * for the bucket type (perhaps the length of the data is indeterminate,
199 * as with pipe and socket buckets), then APR_ENOTIMPL is returned.
200 * @param e The bucket to split
201 * @param point The offset of the first byte in the new bucket
203 apr_status_t (*split)(apr_bucket *e, apr_size_t point);
206 * Copy the bucket structure (not the data), assuming that this is
207 * possible for the bucket type. If it's not, APR_ENOTIMPL is returned.
208 * @param e The bucket to copy
209 * @param c Returns a pointer to the new bucket
211 apr_status_t (*copy)(apr_bucket *e, apr_bucket **c);
216 * apr_bucket structures are allocated on the malloc() heap and
217 * their lifetime is controlled by the parent apr_bucket_brigade
218 * structure. Buckets can move from one brigade to another e.g. by
219 * calling APR_BRIGADE_CONCAT(). In general the data in a bucket has
220 * the same lifetime as the bucket and is freed when the bucket is
221 * destroyed; if the data is shared by more than one bucket (e.g.
222 * after a split) the data is freed when the last bucket goes away.
225 /** Links to the rest of the brigade */
226 APR_RING_ENTRY(apr_bucket) link;
227 /** The type of bucket. */
228 const apr_bucket_type_t *type;
229 /** The length of the data in the bucket. This could have been implemented
230 * with a function, but this is an optimization, because the most
231 * common thing to do will be to get the length. If the length is unknown,
232 * the value of this field will be (apr_size_t)(-1).
235 /** The start of the data in the bucket relative to the private base
236 * pointer. The vast majority of bucket types allow a fixed block of
237 * data to be referenced by multiple buckets, each bucket pointing to
238 * a different segment of the data. That segment starts at base+start
239 * and ends at base+start+length.
240 * If the length == (apr_size_t)(-1), then start == -1.
243 /** type-dependent data hangs off this pointer */
246 * Pointer to function used to free the bucket. This function should
247 * always be defined and it should be consistent with the memory
248 * function used to allocate the bucket. For example, if malloc() is
249 * used to allocate the bucket, this pointer should point to free().
250 * @param e Pointer to the bucket being freed
252 void (*free)(void *e);
253 /** The freelist from which this bucket was allocated */
254 apr_bucket_alloc_t *list;
257 /** A list of buckets */
258 struct apr_bucket_brigade {
259 /** The pool to associate the brigade with. The data is not allocated out
260 * of the pool, but a cleanup is registered with this pool. If the
261 * brigade is destroyed by some mechanism other than pool destruction,
262 * the destroying function is responsible for killing the cleanup.
265 /** The buckets in the brigade are on this list. */
267 * The apr_bucket_list structure doesn't actually need a name tag
268 * because it has no existence independent of struct apr_bucket_brigade;
269 * the ring macros are designed so that you can leave the name tag
270 * argument empty in this situation but apparently the Windows compiler
273 APR_RING_HEAD(apr_bucket_list, apr_bucket) list;
274 /** The freelist from which this bucket was allocated */
275 apr_bucket_alloc_t *bucket_alloc;
280 * Function called when a brigade should be flushed
282 typedef apr_status_t (*apr_brigade_flush)(apr_bucket_brigade *bb, void *ctx);
285 * define APR_BUCKET_DEBUG if you want your brigades to be checked for
286 * validity at every possible instant. this will slow your code down
287 * substantially but is a very useful debugging tool.
289 #ifdef APR_BUCKET_DEBUG
291 #define APR_BRIGADE_CHECK_CONSISTENCY(b) \
292 APR_RING_CHECK_CONSISTENCY(&(b)->list, apr_bucket, link)
294 #define APR_BUCKET_CHECK_CONSISTENCY(e) \
295 APR_RING_CHECK_ELEM_CONSISTENCY((e), apr_bucket, link)
299 * checks the ring pointers in a bucket brigade for consistency. an
300 * abort() will be triggered if any inconsistencies are found.
301 * note: this is a no-op unless APR_BUCKET_DEBUG is defined.
302 * @param b The brigade
304 #define APR_BRIGADE_CHECK_CONSISTENCY(b)
306 * checks the brigade a bucket is in for ring consistency. an
307 * abort() will be triggered if any inconsistencies are found.
308 * note: this is a no-op unless APR_BUCKET_DEBUG is defined.
309 * @param e The bucket
311 #define APR_BUCKET_CHECK_CONSISTENCY(e)
316 * Wrappers around the RING macros to reduce the verbosity of the code
317 * that handles bucket brigades.
320 * The magic pointer value that indicates the head of the brigade
321 * @remark This is used to find the beginning and end of the brigade, eg:
323 * while (e != APR_BRIGADE_SENTINEL(b)) {
325 * e = APR_BUCKET_NEXT(e);
328 * @param b The brigade
329 * @return The magic pointer value
331 #define APR_BRIGADE_SENTINEL(b) APR_RING_SENTINEL(&(b)->list, apr_bucket, link)
334 * Determine if the bucket brigade is empty
335 * @param b The brigade to check
336 * @return true or false
338 #define APR_BRIGADE_EMPTY(b) APR_RING_EMPTY(&(b)->list, apr_bucket, link)
341 * Return the first bucket in a brigade
342 * @param b The brigade to query
343 * @return The first bucket in the brigade
345 #define APR_BRIGADE_FIRST(b) APR_RING_FIRST(&(b)->list)
347 * Return the last bucket in a brigade
348 * @param b The brigade to query
349 * @return The last bucket in the brigade
351 #define APR_BRIGADE_LAST(b) APR_RING_LAST(&(b)->list)
354 * Insert a list of buckets at the front of a brigade
355 * @param b The brigade to add to
356 * @param e The first bucket in a list of buckets to insert
358 #define APR_BRIGADE_INSERT_HEAD(b, e) do { \
359 apr_bucket *ap__b = (e); \
360 APR_RING_INSERT_HEAD(&(b)->list, ap__b, apr_bucket, link); \
361 APR_BRIGADE_CHECK_CONSISTENCY((b)); \
365 * Insert a list of buckets at the end of a brigade
366 * @param b The brigade to add to
367 * @param e The first bucket in a list of buckets to insert
369 #define APR_BRIGADE_INSERT_TAIL(b, e) do { \
370 apr_bucket *ap__b = (e); \
371 APR_RING_INSERT_TAIL(&(b)->list, ap__b, apr_bucket, link); \
372 APR_BRIGADE_CHECK_CONSISTENCY((b)); \
376 * Concatenate brigade b onto the end of brigade a, leaving brigade b empty
377 * @param a The first brigade
378 * @param b The second brigade
380 #define APR_BRIGADE_CONCAT(a, b) do { \
381 APR_RING_CONCAT(&(a)->list, &(b)->list, apr_bucket, link); \
382 APR_BRIGADE_CHECK_CONSISTENCY((a)); \
386 * Prepend brigade b onto the beginning of brigade a, leaving brigade b empty
387 * @param a The first brigade
388 * @param b The second brigade
390 #define APR_BRIGADE_PREPEND(a, b) do { \
391 APR_RING_PREPEND(&(a)->list, &(b)->list, apr_bucket, link); \
392 APR_BRIGADE_CHECK_CONSISTENCY((a)); \
396 * Insert a list of buckets before a specified bucket
397 * @param a The bucket to insert before
398 * @param b The buckets to insert
400 #define APR_BUCKET_INSERT_BEFORE(a, b) do { \
401 apr_bucket *ap__a = (a), *ap__b = (b); \
402 APR_RING_INSERT_BEFORE(ap__a, ap__b, link); \
403 APR_BUCKET_CHECK_CONSISTENCY(ap__a); \
407 * Insert a list of buckets after a specified bucket
408 * @param a The bucket to insert after
409 * @param b The buckets to insert
411 #define APR_BUCKET_INSERT_AFTER(a, b) do { \
412 apr_bucket *ap__a = (a), *ap__b = (b); \
413 APR_RING_INSERT_AFTER(ap__a, ap__b, link); \
414 APR_BUCKET_CHECK_CONSISTENCY(ap__a); \
418 * Get the next bucket in the list
419 * @param e The current bucket
420 * @return The next bucket
422 #define APR_BUCKET_NEXT(e) APR_RING_NEXT((e), link)
424 * Get the previous bucket in the list
425 * @param e The current bucket
426 * @return The previous bucket
428 #define APR_BUCKET_PREV(e) APR_RING_PREV((e), link)
431 * Remove a bucket from its bucket brigade
432 * @param e The bucket to remove
434 #define APR_BUCKET_REMOVE(e) APR_RING_REMOVE((e), link)
437 * Initialize a new bucket's prev/next pointers
438 * @param e The bucket to initialize
440 #define APR_BUCKET_INIT(e) APR_RING_ELEM_INIT((e), link)
443 * Determine if a bucket contains metadata. An empty bucket is
444 * safe to arbitrarily remove if and only if this is false.
445 * @param e The bucket to inspect
446 * @return true or false
448 #define APR_BUCKET_IS_METADATA(e) ((e)->type->is_metadata)
451 * Determine if a bucket is a FLUSH bucket
452 * @param e The bucket to inspect
453 * @return true or false
455 #define APR_BUCKET_IS_FLUSH(e) ((e)->type == &apr_bucket_type_flush)
457 * Determine if a bucket is an EOS bucket
458 * @param e The bucket to inspect
459 * @return true or false
461 #define APR_BUCKET_IS_EOS(e) ((e)->type == &apr_bucket_type_eos)
463 * Determine if a bucket is a FILE bucket
464 * @param e The bucket to inspect
465 * @return true or false
467 #define APR_BUCKET_IS_FILE(e) ((e)->type == &apr_bucket_type_file)
469 * Determine if a bucket is a PIPE bucket
470 * @param e The bucket to inspect
471 * @return true or false
473 #define APR_BUCKET_IS_PIPE(e) ((e)->type == &apr_bucket_type_pipe)
475 * Determine if a bucket is a SOCKET bucket
476 * @param e The bucket to inspect
477 * @return true or false
479 #define APR_BUCKET_IS_SOCKET(e) ((e)->type == &apr_bucket_type_socket)
481 * Determine if a bucket is a HEAP bucket
482 * @param e The bucket to inspect
483 * @return true or false
485 #define APR_BUCKET_IS_HEAP(e) ((e)->type == &apr_bucket_type_heap)
487 * Determine if a bucket is a TRANSIENT bucket
488 * @param e The bucket to inspect
489 * @return true or false
491 #define APR_BUCKET_IS_TRANSIENT(e) ((e)->type == &apr_bucket_type_transient)
493 * Determine if a bucket is a IMMORTAL bucket
494 * @param e The bucket to inspect
495 * @return true or false
497 #define APR_BUCKET_IS_IMMORTAL(e) ((e)->type == &apr_bucket_type_immortal)
500 * Determine if a bucket is a MMAP bucket
501 * @param e The bucket to inspect
502 * @return true or false
504 #define APR_BUCKET_IS_MMAP(e) ((e)->type == &apr_bucket_type_mmap)
507 * Determine if a bucket is a POOL bucket
508 * @param e The bucket to inspect
509 * @return true or false
511 #define APR_BUCKET_IS_POOL(e) ((e)->type == &apr_bucket_type_pool)
514 * General-purpose reference counting for the various bucket types.
516 * Any bucket type that keeps track of the resources it uses (i.e.
517 * most of them except for IMMORTAL, TRANSIENT, and EOS) needs to
518 * attach a reference count to the resource so that it can be freed
519 * when the last bucket that uses it goes away. Resource-sharing may
520 * occur because of bucket splits or buckets that refer to globally
523 /** @see apr_bucket_refcount */
524 typedef struct apr_bucket_refcount apr_bucket_refcount;
526 * The structure used to manage the shared resource must start with an
527 * apr_bucket_refcount which is updated by the general-purpose refcount
528 * code. A pointer to the bucket-type-dependent private data structure
529 * can be cast to a pointer to an apr_bucket_refcount and vice versa.
531 struct apr_bucket_refcount {
532 /** The number of references to this bucket */
536 /* ***** Reference-counted bucket types ***** */
538 /** @see apr_bucket_heap */
539 typedef struct apr_bucket_heap apr_bucket_heap;
541 * A bucket referring to data allocated off the heap.
543 struct apr_bucket_heap {
544 /** Number of buckets using this memory */
545 apr_bucket_refcount refcount;
546 /** The start of the data actually allocated. This should never be
547 * modified, it is only used to free the bucket.
550 /** how much memory was allocated */
551 apr_size_t alloc_len;
552 /** function to use to delete the data */
553 void (*free_func)(void *data);
556 /** @see apr_bucket_pool */
557 typedef struct apr_bucket_pool apr_bucket_pool;
559 * A bucket referring to data allocated from a pool
561 struct apr_bucket_pool {
562 /** The pool bucket must be able to be easily morphed to a heap
563 * bucket if the pool gets cleaned up before all references are
564 * destroyed. This apr_bucket_heap structure is populated automatically
565 * when the pool gets cleaned up, and subsequent calls to pool_read()
566 * will result in the apr_bucket in question being morphed into a
567 * regular heap bucket. (To avoid having to do many extra refcount
568 * manipulations and b->data manipulations, the apr_bucket_pool
569 * struct actually *contains* the apr_bucket_heap struct that it
570 * will become as its first element; the two share their
571 * apr_bucket_refcount members.)
573 apr_bucket_heap heap;
574 /** The block of data actually allocated from the pool.
575 * Segments of this block are referenced by adjusting
576 * the start and length of the apr_bucket accordingly.
577 * This will be NULL after the pool gets cleaned up.
580 /** The pool the data was allocated from. When the pool
581 * is cleaned up, this gets set to NULL as an indicator
582 * to pool_read() that the data is now on the heap and
583 * so it should morph the bucket into a regular heap
584 * bucket before continuing.
587 /** The freelist this structure was allocated from, which is
588 * needed in the cleanup phase in order to allocate space on the heap
590 apr_bucket_alloc_t *list;
594 /** @see apr_bucket_mmap */
595 typedef struct apr_bucket_mmap apr_bucket_mmap;
597 * A bucket referring to an mmap()ed file
599 struct apr_bucket_mmap {
600 /** Number of buckets using this memory */
601 apr_bucket_refcount refcount;
602 /** The mmap this sub_bucket refers to */
607 /** @see apr_bucket_file */
608 typedef struct apr_bucket_file apr_bucket_file;
610 * A bucket referring to an file
612 struct apr_bucket_file {
613 /** Number of buckets using this memory */
614 apr_bucket_refcount refcount;
615 /** The file this bucket refers to */
617 /** The pool into which any needed structures should
618 * be created while reading from this file bucket */
619 apr_pool_t *readpool;
621 /** Whether this bucket should be memory-mapped if
622 * a caller tries to read from it */
624 #endif /* APR_HAS_MMAP */
627 /** @see apr_bucket_structs */
628 typedef union apr_bucket_structs apr_bucket_structs;
630 * A union of all bucket structures so we know what
633 union apr_bucket_structs {
634 apr_bucket b; /**< Bucket */
635 apr_bucket_heap heap; /**< Heap */
636 apr_bucket_pool pool; /**< Pool */
638 apr_bucket_mmap mmap; /**< MMap */
640 apr_bucket_file file; /**< File */
644 * The amount that apr_bucket_alloc() should allocate in the common case.
645 * Note: this is twice as big as apr_bucket_structs to allow breathing
646 * room for third-party bucket types.
648 #define APR_BUCKET_ALLOC_SIZE APR_ALIGN_DEFAULT(2*sizeof(apr_bucket_structs))
650 /* ***** Bucket Brigade Functions ***** */
652 * Create a new bucket brigade. The bucket brigade is originally empty.
653 * @param p The pool to associate with the brigade. Data is not allocated out
654 * of the pool, but a cleanup is registered.
655 * @param list The bucket allocator to use
656 * @return The empty bucket brigade
658 APU_DECLARE(apr_bucket_brigade *) apr_brigade_create(apr_pool_t *p,
659 apr_bucket_alloc_t *list);
662 * destroy an entire bucket brigade. This includes destroying all of the
663 * buckets within the bucket brigade's bucket list.
664 * @param b The bucket brigade to destroy
666 APU_DECLARE(apr_status_t) apr_brigade_destroy(apr_bucket_brigade *b);
669 * empty out an entire bucket brigade. This includes destroying all of the
670 * buckets within the bucket brigade's bucket list. This is similar to
671 * apr_brigade_destroy(), except that it does not deregister the brigade's
672 * pool cleanup function.
673 * @param data The bucket brigade to clean up
674 * @remark Generally, you should use apr_brigade_destroy(). This function
675 * can be useful in situations where you have a single brigade that
676 * you wish to reuse many times by destroying all of the buckets in
677 * the brigade and putting new buckets into it later.
679 APU_DECLARE(apr_status_t) apr_brigade_cleanup(void *data);
682 * Move the buckets from the tail end of the existing brigade @a b into
683 * the brigade @a a. If @a a is NULL a new brigade is created. Buckets
684 * from @a e to the last bucket (inclusively) of brigade @a b are moved
685 * from @a b to the returned brigade @a a.
687 * @param b The brigade to split
688 * @param e The first bucket to move
689 * @param a The brigade which should be used for the result or NULL if
690 * a new brigade should be created.
691 * @return The brigade supplied in @param a or a new one if @param a was NULL.
692 * @warning Note that this function allocates a new brigade if @param a is
693 * NULL so memory consumption should be carefully considered.
695 APU_DECLARE(apr_bucket_brigade *) apr_brigade_split_ex(apr_bucket_brigade *b,
697 apr_bucket_brigade *a);
700 * Create a new bucket brigade and move the buckets from the tail end
701 * of an existing brigade into the new brigade. Buckets from
702 * @param e to the last bucket (inclusively) of brigade @param b
703 * are moved from @param b to the returned brigade.
704 * @param b The brigade to split
705 * @param e The first bucket to move
706 * @return The new brigade
707 * @warning Note that this function always allocates a new brigade
708 * so memory consumption should be carefully considered.
710 APU_DECLARE(apr_bucket_brigade *) apr_brigade_split(apr_bucket_brigade *b,
714 * Partition a bucket brigade at a given offset (in bytes from the start of
715 * the brigade). This is useful whenever a filter wants to use known ranges
716 * of bytes from the brigade; the ranges can even overlap.
717 * @param b The brigade to partition
718 * @param point The offset at which to partition the brigade
719 * @param after_point Returns a pointer to the first bucket after the partition
720 * @return APR_SUCCESS on success, APR_INCOMPLETE if the contents of the
721 * brigade were shorter than @a point, or an error code.
722 * @remark if APR_INCOMPLETE is returned, @a after_point will be set to
723 * the brigade sentinel.
725 APU_DECLARE(apr_status_t) apr_brigade_partition(apr_bucket_brigade *b,
727 apr_bucket **after_point);
730 * Return the total length of the brigade.
731 * @param bb The brigade to compute the length of
732 * @param read_all Read unknown-length buckets to force a size
733 * @param length Returns the length of the brigade (up to the end, or up
734 * to a bucket read error), or -1 if the brigade has buckets
735 * of indeterminate length and read_all is 0.
737 APU_DECLARE(apr_status_t) apr_brigade_length(apr_bucket_brigade *bb,
742 * Take a bucket brigade and store the data in a flat char*
743 * @param bb The bucket brigade to create the char* from
744 * @param c The char* to write into
745 * @param len The maximum length of the char array. On return, it is the
746 * actual length of the char array.
748 APU_DECLARE(apr_status_t) apr_brigade_flatten(apr_bucket_brigade *bb,
753 * Creates a pool-allocated string representing a flat bucket brigade
754 * @param bb The bucket brigade to create the char array from
755 * @param c On return, the allocated char array
756 * @param len On return, the length of the char array.
757 * @param pool The pool to allocate the string from.
759 APU_DECLARE(apr_status_t) apr_brigade_pflatten(apr_bucket_brigade *bb,
765 * Split a brigade to represent one LF line.
766 * @param bbOut The bucket brigade that will have the LF line appended to.
767 * @param bbIn The input bucket brigade to search for a LF-line.
768 * @param block The blocking mode to be used to split the line.
769 * @param maxbytes The maximum bytes to read. If this many bytes are seen
770 * without a LF, the brigade will contain a partial line.
772 APU_DECLARE(apr_status_t) apr_brigade_split_line(apr_bucket_brigade *bbOut,
773 apr_bucket_brigade *bbIn,
774 apr_read_type_e block,
778 * Create an iovec of the elements in a bucket_brigade... return number
779 * of elements used. This is useful for writing to a file or to the
780 * network efficiently.
781 * @param b The bucket brigade to create the iovec from
782 * @param vec The iovec to create
783 * @param nvec The number of elements in the iovec. On return, it is the
784 * number of iovec elements actually filled out.
786 APU_DECLARE(apr_status_t) apr_brigade_to_iovec(apr_bucket_brigade *b,
787 struct iovec *vec, int *nvec);
790 * This function writes a list of strings into a bucket brigade.
791 * @param b The bucket brigade to add to
792 * @param flush The flush function to use if the brigade is full
793 * @param ctx The structure to pass to the flush function
794 * @param va A list of strings to add
795 * @return APR_SUCCESS or error code.
797 APU_DECLARE(apr_status_t) apr_brigade_vputstrs(apr_bucket_brigade *b,
798 apr_brigade_flush flush,
803 * This function writes a string into a bucket brigade.
805 * The apr_brigade_write function attempts to be efficient with the
806 * handling of heap buckets. Regardless of the amount of data stored
807 * inside a heap bucket, heap buckets are a fixed size to promote their
810 * If an attempt is made to write a string to a brigade that already
811 * ends with a heap bucket, this function will attempt to pack the
812 * string into the remaining space in the previous heap bucket, before
813 * allocating a new heap bucket.
815 * This function always returns APR_SUCCESS, unless a flush function is
816 * passed, in which case the return value of the flush function will be
818 * @param b The bucket brigade to add to
819 * @param flush The flush function to use if the brigade is full
820 * @param ctx The structure to pass to the flush function
821 * @param str The string to add
822 * @param nbyte The number of bytes to write
823 * @return APR_SUCCESS or error code
825 APU_DECLARE(apr_status_t) apr_brigade_write(apr_bucket_brigade *b,
826 apr_brigade_flush flush, void *ctx,
827 const char *str, apr_size_t nbyte);
830 * This function writes multiple strings into a bucket brigade.
831 * @param b The bucket brigade to add to
832 * @param flush The flush function to use if the brigade is full
833 * @param ctx The structure to pass to the flush function
834 * @param vec The strings to add (address plus length for each)
835 * @param nvec The number of entries in iovec
836 * @return APR_SUCCESS or error code
838 APU_DECLARE(apr_status_t) apr_brigade_writev(apr_bucket_brigade *b,
839 apr_brigade_flush flush,
841 const struct iovec *vec,
845 * This function writes a string into a bucket brigade.
846 * @param bb The bucket brigade to add to
847 * @param flush The flush function to use if the brigade is full
848 * @param ctx The structure to pass to the flush function
849 * @param str The string to add
850 * @return APR_SUCCESS or error code
852 APU_DECLARE(apr_status_t) apr_brigade_puts(apr_bucket_brigade *bb,
853 apr_brigade_flush flush, void *ctx,
857 * This function writes a character into a bucket brigade.
858 * @param b The bucket brigade to add to
859 * @param flush The flush function to use if the brigade is full
860 * @param ctx The structure to pass to the flush function
861 * @param c The character to add
862 * @return APR_SUCCESS or error code
864 APU_DECLARE(apr_status_t) apr_brigade_putc(apr_bucket_brigade *b,
865 apr_brigade_flush flush, void *ctx,
869 * This function writes an unspecified number of strings into a bucket brigade.
870 * @param b The bucket brigade to add to
871 * @param flush The flush function to use if the brigade is full
872 * @param ctx The structure to pass to the flush function
873 * @param ... The strings to add
874 * @return APR_SUCCESS or error code
876 APU_DECLARE_NONSTD(apr_status_t) apr_brigade_putstrs(apr_bucket_brigade *b,
877 apr_brigade_flush flush,
881 * Evaluate a printf and put the resulting string at the end
882 * of the bucket brigade.
883 * @param b The brigade to write to
884 * @param flush The flush function to use if the brigade is full
885 * @param ctx The structure to pass to the flush function
886 * @param fmt The format of the string to write
887 * @param ... The arguments to fill out the format
888 * @return APR_SUCCESS or error code
890 APU_DECLARE_NONSTD(apr_status_t) apr_brigade_printf(apr_bucket_brigade *b,
891 apr_brigade_flush flush,
893 const char *fmt, ...)
894 __attribute__((format(printf,4,5)));
897 * Evaluate a printf and put the resulting string at the end
898 * of the bucket brigade.
899 * @param b The brigade to write to
900 * @param flush The flush function to use if the brigade is full
901 * @param ctx The structure to pass to the flush function
902 * @param fmt The format of the string to write
903 * @param va The arguments to fill out the format
904 * @return APR_SUCCESS or error code
906 APU_DECLARE(apr_status_t) apr_brigade_vprintf(apr_bucket_brigade *b,
907 apr_brigade_flush flush,
909 const char *fmt, va_list va);
912 * Utility function to insert a file (or a segment of a file) onto the
913 * end of the brigade. The file is split into multiple buckets if it
914 * is larger than the maximum size which can be represented by a
916 * @param bb the brigade to insert into
917 * @param f the file to insert
918 * @param start the offset of the start of the segment
919 * @param len the length of the segment of the file to insert
920 * @param p pool from which file buckets are allocated
921 * @return the last bucket inserted
923 APU_DECLARE(apr_bucket *) apr_brigade_insert_file(apr_bucket_brigade *bb,
931 /* ***** Bucket freelist functions ***** */
933 * Create a bucket allocator.
934 * @param p This pool's underlying apr_allocator_t is used to allocate memory
935 * for the bucket allocator. When the pool is destroyed, the bucket
936 * allocator's cleanup routine will free all memory that has been
938 * @remark The reason the allocator gets its memory from the pool's
939 * apr_allocator_t rather than from the pool itself is because
940 * the bucket allocator will free large memory blocks back to the
941 * allocator when it's done with them, thereby preventing memory
942 * footprint growth that would occur if we allocated from the pool.
943 * @warning The allocator must never be used by more than one thread at a time.
945 APU_DECLARE_NONSTD(apr_bucket_alloc_t *) apr_bucket_alloc_create(apr_pool_t *p);
948 * Create a bucket allocator.
949 * @param allocator This apr_allocator_t is used to allocate both the bucket
950 * allocator and all memory handed out by the bucket allocator. The
951 * caller is responsible for destroying the bucket allocator and the
952 * apr_allocator_t -- no automatic cleanups will happen.
953 * @warning The allocator must never be used by more than one thread at a time.
955 APU_DECLARE_NONSTD(apr_bucket_alloc_t *) apr_bucket_alloc_create_ex(apr_allocator_t *allocator);
958 * Destroy a bucket allocator.
959 * @param list The allocator to be destroyed
961 APU_DECLARE_NONSTD(void) apr_bucket_alloc_destroy(apr_bucket_alloc_t *list);
964 * Allocate memory for use by the buckets.
965 * @param size The amount to allocate.
966 * @param list The allocator from which to allocate the memory.
968 APU_DECLARE_NONSTD(void *) apr_bucket_alloc(apr_size_t size, apr_bucket_alloc_t *list);
971 * Free memory previously allocated with apr_bucket_alloc().
972 * @param block The block of memory to be freed.
974 APU_DECLARE_NONSTD(void) apr_bucket_free(void *block);
977 /* ***** Bucket Functions ***** */
979 * Free the resources used by a bucket. If multiple buckets refer to
980 * the same resource it is freed when the last one goes away.
981 * @see apr_bucket_delete()
982 * @param e The bucket to destroy
984 #define apr_bucket_destroy(e) do { \
985 (e)->type->destroy((e)->data); \
990 * Delete a bucket by removing it from its brigade (if any) and then
992 * @remark This mainly acts as an aid in avoiding code verbosity. It is
993 * the preferred exact equivalent to:
995 * APR_BUCKET_REMOVE(e);
996 * apr_bucket_destroy(e);
998 * @param e The bucket to delete
1000 #define apr_bucket_delete(e) do { \
1001 APR_BUCKET_REMOVE(e); \
1002 apr_bucket_destroy(e); \
1006 * Read some data from the bucket.
1008 * The apr_bucket_read function returns a convenient amount of data
1009 * from the bucket provided, writing the address and length of the
1010 * data to the pointers provided by the caller. The function tries
1011 * as hard as possible to avoid a memory copy.
1013 * Buckets are expected to be a member of a brigade at the time they
1016 * In typical application code, buckets are read in a loop, and after
1017 * each bucket is read and processed, it is moved or deleted from the
1018 * brigade and the next bucket read.
1020 * The definition of "convenient" depends on the type of bucket that
1021 * is being read, and is decided by APR. In the case of memory based
1022 * buckets such as heap and immortal buckets, a pointer will be
1023 * returned to the location of the buffer containing the complete
1024 * contents of the bucket.
1026 * Some buckets, such as the socket bucket, might have no concept
1027 * of length. If an attempt is made to read such a bucket, the
1028 * apr_bucket_read function will read a convenient amount of data
1029 * from the socket. The socket bucket is magically morphed into a
1030 * heap bucket containing the just-read data, and a new socket bucket
1031 * is inserted just after this heap bucket.
1033 * To understand why apr_bucket_read might do this, consider the loop
1034 * described above to read and process buckets. The current bucket
1035 * is magically morphed into a heap bucket and returned to the caller.
1036 * The caller processes the data, and deletes the heap bucket, moving
1037 * onto the next bucket, the new socket bucket. This process repeats,
1038 * giving the illusion of a bucket brigade that contains potentially
1039 * infinite amounts of data. It is up to the caller to decide at what
1040 * point to stop reading buckets.
1042 * Some buckets, such as the file bucket, might have a fixed size,
1043 * but be significantly larger than is practical to store in RAM in
1044 * one go. As with the socket bucket, if an attempt is made to read
1045 * from a file bucket, the file bucket is magically morphed into a
1046 * heap bucket containing a convenient amount of data read from the
1047 * current offset in the file. During the read, the offset will be
1048 * moved forward on the file, and a new file bucket will be inserted
1049 * directly after the current bucket representing the remainder of the
1050 * file. If the heap bucket was large enough to store the whole
1051 * remainder of the file, no more file buckets are inserted, and the
1052 * file bucket will disappear completely.
1054 * The pattern for reading buckets described above does create the
1055 * illusion that the code is willing to swallow buckets that might be
1056 * too large for the system to handle in one go. This however is just
1057 * an illusion: APR will always ensure that large (file) or infinite
1058 * (socket) buckets are broken into convenient bite sized heap buckets
1059 * before data is returned to the caller.
1061 * There is a potential gotcha to watch for: if buckets are read in a
1062 * loop, and aren't deleted after being processed, the potentially large
1063 * bucket will slowly be converted into RAM resident heap buckets. If
1064 * the file is larger than available RAM, an out of memory condition
1065 * could be caused if the application is not careful to manage this.
1067 * @param e The bucket to read from
1068 * @param str The location to store a pointer to the data in
1069 * @param len The location to store the amount of data read
1070 * @param block Whether the read function blocks
1072 #define apr_bucket_read(e,str,len,block) (e)->type->read(e, str, len, block)
1075 * Setaside data so that stack data is not destroyed on returning from
1077 * @param e The bucket to setaside
1078 * @param p The pool to setaside into
1080 #define apr_bucket_setaside(e,p) (e)->type->setaside(e,p)
1083 * Split one bucket in two at the point provided.
1085 * Once split, the original bucket becomes the first of the two new buckets.
1087 * (It is assumed that the bucket is a member of a brigade when this
1088 * function is called).
1089 * @param e The bucket to split
1090 * @param point The offset to split the bucket at
1092 #define apr_bucket_split(e,point) (e)->type->split(e, point)
1096 * @param e The bucket to copy
1097 * @param c Returns a pointer to the new bucket
1099 #define apr_bucket_copy(e,c) (e)->type->copy(e, c)
1101 /* Bucket type handling */
1104 * This function simply returns APR_SUCCESS to denote that the bucket does
1105 * not require anything to happen for its setaside() function. This is
1106 * appropriate for buckets that have "immortal" data -- the data will live
1107 * at least as long as the bucket.
1108 * @param data The bucket to setaside
1109 * @param pool The pool defining the desired lifetime of the bucket data
1110 * @return APR_SUCCESS
1112 APU_DECLARE_NONSTD(apr_status_t) apr_bucket_setaside_noop(apr_bucket *data,
1116 * A place holder function that signifies that the setaside function was not
1117 * implemented for this bucket
1118 * @param data The bucket to setaside
1119 * @param pool The pool defining the desired lifetime of the bucket data
1120 * @return APR_ENOTIMPL
1122 APU_DECLARE_NONSTD(apr_status_t) apr_bucket_setaside_notimpl(apr_bucket *data,
1126 * A place holder function that signifies that the split function was not
1127 * implemented for this bucket
1128 * @param data The bucket to split
1129 * @param point The location to split the bucket
1130 * @return APR_ENOTIMPL
1132 APU_DECLARE_NONSTD(apr_status_t) apr_bucket_split_notimpl(apr_bucket *data,
1136 * A place holder function that signifies that the copy function was not
1137 * implemented for this bucket
1138 * @param e The bucket to copy
1139 * @param c Returns a pointer to the new bucket
1140 * @return APR_ENOTIMPL
1142 APU_DECLARE_NONSTD(apr_status_t) apr_bucket_copy_notimpl(apr_bucket *e,
1146 * A place holder function that signifies that this bucket does not need
1147 * to do anything special to be destroyed. That's only the case for buckets
1148 * that either have no data (metadata buckets) or buckets whose data pointer
1149 * points to something that's not a bucket-type-specific structure, as with
1150 * simple buckets where data points to a string and pipe buckets where data
1151 * points directly to the apr_file_t.
1152 * @param data The bucket data to destroy
1154 APU_DECLARE_NONSTD(void) apr_bucket_destroy_noop(void *data);
1157 * There is no apr_bucket_destroy_notimpl, because destruction is required
1158 * to be implemented (it could be a noop, but only if that makes sense for
1162 /* There is no apr_bucket_read_notimpl, because it is a required function
1166 /* All of the bucket types implemented by the core */
1168 * The flush bucket type. This signifies that all data should be flushed to
1169 * the next filter. The flush bucket should be sent with the other buckets.
1171 APU_DECLARE_DATA extern const apr_bucket_type_t apr_bucket_type_flush;
1173 * The EOS bucket type. This signifies that there will be no more data, ever.
1174 * All filters MUST send all data to the next filter when they receive a
1175 * bucket of this type
1177 APU_DECLARE_DATA extern const apr_bucket_type_t apr_bucket_type_eos;
1179 * The FILE bucket type. This bucket represents a file on disk
1181 APU_DECLARE_DATA extern const apr_bucket_type_t apr_bucket_type_file;
1183 * The HEAP bucket type. This bucket represents a data allocated from the
1186 APU_DECLARE_DATA extern const apr_bucket_type_t apr_bucket_type_heap;
1189 * The MMAP bucket type. This bucket represents an MMAP'ed file
1191 APU_DECLARE_DATA extern const apr_bucket_type_t apr_bucket_type_mmap;
1194 * The POOL bucket type. This bucket represents a data that was allocated
1195 * from a pool. IF this bucket is still available when the pool is cleared,
1196 * the data is copied on to the heap.
1198 APU_DECLARE_DATA extern const apr_bucket_type_t apr_bucket_type_pool;
1200 * The PIPE bucket type. This bucket represents a pipe to another program.
1202 APU_DECLARE_DATA extern const apr_bucket_type_t apr_bucket_type_pipe;
1204 * The IMMORTAL bucket type. This bucket represents a segment of data that
1205 * the creator is willing to take responsibility for. The core will do
1206 * nothing with the data in an immortal bucket
1208 APU_DECLARE_DATA extern const apr_bucket_type_t apr_bucket_type_immortal;
1210 * The TRANSIENT bucket type. This bucket represents a data allocated off
1211 * the stack. When the setaside function is called, this data is copied on
1214 APU_DECLARE_DATA extern const apr_bucket_type_t apr_bucket_type_transient;
1216 * The SOCKET bucket type. This bucket represents a socket to another machine
1218 APU_DECLARE_DATA extern const apr_bucket_type_t apr_bucket_type_socket;
1221 /* ***** Simple buckets ***** */
1224 * Split a simple bucket into two at the given point. Most non-reference
1225 * counting buckets that allow multiple references to the same block of
1226 * data (eg transient and immortal) will use this as their split function
1227 * without any additional type-specific handling.
1228 * @param b The bucket to be split
1229 * @param point The offset of the first byte in the new bucket
1230 * @return APR_EINVAL if the point is not within the bucket;
1231 * APR_ENOMEM if allocation failed;
1234 APU_DECLARE_NONSTD(apr_status_t) apr_bucket_simple_split(apr_bucket *b,
1238 * Copy a simple bucket. Most non-reference-counting buckets that allow
1239 * multiple references to the same block of data (eg transient and immortal)
1240 * will use this as their copy function without any additional type-specific
1242 * @param a The bucket to copy
1243 * @param b Returns a pointer to the new bucket
1244 * @return APR_ENOMEM if allocation failed;
1247 APU_DECLARE_NONSTD(apr_status_t) apr_bucket_simple_copy(apr_bucket *a,
1251 /* ***** Shared, reference-counted buckets ***** */
1254 * Initialize a bucket containing reference-counted data that may be
1255 * shared. The caller must allocate the bucket if necessary and
1256 * initialize its type-dependent fields, and allocate and initialize
1257 * its own private data structure. This function should only be called
1258 * by type-specific bucket creation functions.
1259 * @param b The bucket to initialize
1260 * @param data A pointer to the private data structure
1261 * with the reference count at the start
1262 * @param start The start of the data in the bucket
1263 * relative to the private base pointer
1264 * @param length The length of the data in the bucket
1265 * @return The new bucket, or NULL if allocation failed
1267 APU_DECLARE(apr_bucket *) apr_bucket_shared_make(apr_bucket *b, void *data,
1272 * Decrement the refcount of the data in the bucket. This function
1273 * should only be called by type-specific bucket destruction functions.
1274 * @param data The private data pointer from the bucket to be destroyed
1275 * @return TRUE or FALSE; TRUE if the reference count is now
1276 * zero, indicating that the shared resource itself can
1277 * be destroyed by the caller.
1279 APU_DECLARE(int) apr_bucket_shared_destroy(void *data);
1282 * Split a bucket into two at the given point, and adjust the refcount
1283 * to the underlying data. Most reference-counting bucket types will
1284 * be able to use this function as their split function without any
1285 * additional type-specific handling.
1286 * @param b The bucket to be split
1287 * @param point The offset of the first byte in the new bucket
1288 * @return APR_EINVAL if the point is not within the bucket;
1289 * APR_ENOMEM if allocation failed;
1292 APU_DECLARE_NONSTD(apr_status_t) apr_bucket_shared_split(apr_bucket *b,
1296 * Copy a refcounted bucket, incrementing the reference count. Most
1297 * reference-counting bucket types will be able to use this function
1298 * as their copy function without any additional type-specific handling.
1299 * @param a The bucket to copy
1300 * @param b Returns a pointer to the new bucket
1301 * @return APR_ENOMEM if allocation failed;
1304 APU_DECLARE_NONSTD(apr_status_t) apr_bucket_shared_copy(apr_bucket *a,
1308 /* ***** Functions to Create Buckets of varying types ***** */
1310 * Each bucket type foo has two initialization functions:
1311 * apr_bucket_foo_make which sets up some already-allocated memory as a
1312 * bucket of type foo; and apr_bucket_foo_create which allocates memory
1313 * for the bucket, calls apr_bucket_make_foo, and initializes the
1314 * bucket's list pointers. The apr_bucket_foo_make functions are used
1315 * inside the bucket code to change the type of buckets in place;
1316 * other code should call apr_bucket_foo_create. All the initialization
1317 * functions change nothing if they fail.
1321 * Create an End of Stream bucket. This indicates that there is no more data
1322 * coming from down the filter stack. All filters should flush at this point.
1323 * @param list The freelist from which this bucket should be allocated
1324 * @return The new bucket, or NULL if allocation failed
1326 APU_DECLARE(apr_bucket *) apr_bucket_eos_create(apr_bucket_alloc_t *list);
1329 * Make the bucket passed in an EOS bucket. This indicates that there is no
1330 * more data coming from down the filter stack. All filters should flush at
1332 * @param b The bucket to make into an EOS bucket
1333 * @return The new bucket, or NULL if allocation failed
1335 APU_DECLARE(apr_bucket *) apr_bucket_eos_make(apr_bucket *b);
1338 * Create a flush bucket. This indicates that filters should flush their
1339 * data. There is no guarantee that they will flush it, but this is the
1341 * @param list The freelist from which this bucket should be allocated
1342 * @return The new bucket, or NULL if allocation failed
1344 APU_DECLARE(apr_bucket *) apr_bucket_flush_create(apr_bucket_alloc_t *list);
1347 * Make the bucket passed in a FLUSH bucket. This indicates that filters
1348 * should flush their data. There is no guarantee that they will flush it,
1349 * but this is the best we can do.
1350 * @param b The bucket to make into a FLUSH bucket
1351 * @return The new bucket, or NULL if allocation failed
1353 APU_DECLARE(apr_bucket *) apr_bucket_flush_make(apr_bucket *b);
1356 * Create a bucket referring to long-lived data.
1357 * @param buf The data to insert into the bucket
1358 * @param nbyte The size of the data to insert.
1359 * @param list The freelist from which this bucket should be allocated
1360 * @return The new bucket, or NULL if allocation failed
1362 APU_DECLARE(apr_bucket *) apr_bucket_immortal_create(const char *buf,
1364 apr_bucket_alloc_t *list);
1367 * Make the bucket passed in a bucket refer to long-lived data
1368 * @param b The bucket to make into a IMMORTAL bucket
1369 * @param buf The data to insert into the bucket
1370 * @param nbyte The size of the data to insert.
1371 * @return The new bucket, or NULL if allocation failed
1373 APU_DECLARE(apr_bucket *) apr_bucket_immortal_make(apr_bucket *b,
1378 * Create a bucket referring to data on the stack.
1379 * @param buf The data to insert into the bucket
1380 * @param nbyte The size of the data to insert.
1381 * @param list The freelist from which this bucket should be allocated
1382 * @return The new bucket, or NULL if allocation failed
1384 APU_DECLARE(apr_bucket *) apr_bucket_transient_create(const char *buf,
1386 apr_bucket_alloc_t *list);
1389 * Make the bucket passed in a bucket refer to stack data
1390 * @param b The bucket to make into a TRANSIENT bucket
1391 * @param buf The data to insert into the bucket
1392 * @param nbyte The size of the data to insert.
1393 * @return The new bucket, or NULL if allocation failed
1395 APU_DECLARE(apr_bucket *) apr_bucket_transient_make(apr_bucket *b,
1400 * Create a bucket referring to memory on the heap. If the caller asks
1401 * for the data to be copied, this function always allocates 4K of
1402 * memory so that more data can be added to the bucket without
1403 * requiring another allocation. Therefore not all the data may be put
1404 * into the bucket. If copying is not requested then the bucket takes
1405 * over responsibility for free()ing the memory.
1406 * @param buf The buffer to insert into the bucket
1407 * @param nbyte The size of the buffer to insert.
1408 * @param free_func Function to use to free the data; NULL indicates that the
1409 * bucket should make a copy of the data
1410 * @param list The freelist from which this bucket should be allocated
1411 * @return The new bucket, or NULL if allocation failed
1413 APU_DECLARE(apr_bucket *) apr_bucket_heap_create(const char *buf,
1415 void (*free_func)(void *data),
1416 apr_bucket_alloc_t *list);
1418 * Make the bucket passed in a bucket refer to heap data
1419 * @param b The bucket to make into a HEAP bucket
1420 * @param buf The buffer to insert into the bucket
1421 * @param nbyte The size of the buffer to insert.
1422 * @param free_func Function to use to free the data; NULL indicates that the
1423 * bucket should make a copy of the data
1424 * @return The new bucket, or NULL if allocation failed
1426 APU_DECLARE(apr_bucket *) apr_bucket_heap_make(apr_bucket *b, const char *buf,
1428 void (*free_func)(void *data));
1431 * Create a bucket referring to memory allocated from a pool.
1433 * @param buf The buffer to insert into the bucket
1434 * @param length The number of bytes referred to by this bucket
1435 * @param pool The pool the memory was allocated from
1436 * @param list The freelist from which this bucket should be allocated
1437 * @return The new bucket, or NULL if allocation failed
1439 APU_DECLARE(apr_bucket *) apr_bucket_pool_create(const char *buf,
1442 apr_bucket_alloc_t *list);
1445 * Make the bucket passed in a bucket refer to pool data
1446 * @param b The bucket to make into a pool bucket
1447 * @param buf The buffer to insert into the bucket
1448 * @param length The number of bytes referred to by this bucket
1449 * @param pool The pool the memory was allocated from
1450 * @return The new bucket, or NULL if allocation failed
1452 APU_DECLARE(apr_bucket *) apr_bucket_pool_make(apr_bucket *b, const char *buf,
1458 * Create a bucket referring to mmap()ed memory.
1459 * @param mm The mmap to insert into the bucket
1460 * @param start The offset of the first byte in the mmap
1461 * that this bucket refers to
1462 * @param length The number of bytes referred to by this bucket
1463 * @param list The freelist from which this bucket should be allocated
1464 * @return The new bucket, or NULL if allocation failed
1466 APU_DECLARE(apr_bucket *) apr_bucket_mmap_create(apr_mmap_t *mm,
1469 apr_bucket_alloc_t *list);
1472 * Make the bucket passed in a bucket refer to an MMAP'ed file
1473 * @param b The bucket to make into a MMAP bucket
1474 * @param mm The mmap to insert into the bucket
1475 * @param start The offset of the first byte in the mmap
1476 * that this bucket refers to
1477 * @param length The number of bytes referred to by this bucket
1478 * @return The new bucket, or NULL if allocation failed
1480 APU_DECLARE(apr_bucket *) apr_bucket_mmap_make(apr_bucket *b, apr_mmap_t *mm,
1486 * Create a bucket referring to a socket.
1487 * @param thissock The socket to put in the bucket
1488 * @param list The freelist from which this bucket should be allocated
1489 * @return The new bucket, or NULL if allocation failed
1491 APU_DECLARE(apr_bucket *) apr_bucket_socket_create(apr_socket_t *thissock,
1492 apr_bucket_alloc_t *list);
1494 * Make the bucket passed in a bucket refer to a socket
1495 * @param b The bucket to make into a SOCKET bucket
1496 * @param thissock The socket to put in the bucket
1497 * @return The new bucket, or NULL if allocation failed
1499 APU_DECLARE(apr_bucket *) apr_bucket_socket_make(apr_bucket *b,
1500 apr_socket_t *thissock);
1503 * Create a bucket referring to a pipe.
1504 * @param thispipe The pipe to put in the bucket
1505 * @param list The freelist from which this bucket should be allocated
1506 * @return The new bucket, or NULL if allocation failed
1508 APU_DECLARE(apr_bucket *) apr_bucket_pipe_create(apr_file_t *thispipe,
1509 apr_bucket_alloc_t *list);
1512 * Make the bucket passed in a bucket refer to a pipe
1513 * @param b The bucket to make into a PIPE bucket
1514 * @param thispipe The pipe to put in the bucket
1515 * @return The new bucket, or NULL if allocation failed
1517 APU_DECLARE(apr_bucket *) apr_bucket_pipe_make(apr_bucket *b,
1518 apr_file_t *thispipe);
1521 * Create a bucket referring to a file.
1522 * @param fd The file to put in the bucket
1523 * @param offset The offset where the data of interest begins in the file
1524 * @param len The amount of data in the file we are interested in
1525 * @param p The pool into which any needed structures should be created
1526 * while reading from this file bucket
1527 * @param list The freelist from which this bucket should be allocated
1528 * @return The new bucket, or NULL if allocation failed
1529 * @remark If the file is truncated such that the segment of the file
1530 * referenced by the bucket no longer exists, an attempt to read
1531 * from the bucket will fail with APR_EOF.
1532 * @remark apr_brigade_insert_file() should generally be used to
1533 * insert files into brigades, since that function can correctly
1534 * handle large file issues.
1536 APU_DECLARE(apr_bucket *) apr_bucket_file_create(apr_file_t *fd,
1540 apr_bucket_alloc_t *list);
1543 * Make the bucket passed in a bucket refer to a file
1544 * @param b The bucket to make into a FILE bucket
1545 * @param fd The file to put in the bucket
1546 * @param offset The offset where the data of interest begins in the file
1547 * @param len The amount of data in the file we are interested in
1548 * @param p The pool into which any needed structures should be created
1549 * while reading from this file bucket
1550 * @return The new bucket, or NULL if allocation failed
1552 APU_DECLARE(apr_bucket *) apr_bucket_file_make(apr_bucket *b, apr_file_t *fd,
1554 apr_size_t len, apr_pool_t *p);
1557 * Enable or disable memory-mapping for a FILE bucket (default is enabled)
1558 * @param b The bucket
1559 * @param enabled Whether memory-mapping should be enabled
1560 * @return APR_SUCCESS normally, or an error code if the operation fails
1562 APU_DECLARE(apr_status_t) apr_bucket_file_enable_mmap(apr_bucket *b,
1570 #endif /* !APR_BUCKETS_H */