00001 /* Licensed to the Apache Software Foundation (ASF) under one or more 00002 * contributor license agreements. See the NOTICE file distributed with 00003 * this work for additional information regarding copyright ownership. 00004 * The ASF licenses this file to You under the Apache License, Version 2.0 00005 * (the "License"); you may not use this file except in compliance with 00006 * the License. You may obtain a copy of the License at 00007 * 00008 * http://www.apache.org/licenses/LICENSE-2.0 00009 * 00010 * Unless required by applicable law or agreed to in writing, software 00011 * distributed under the License is distributed on an "AS IS" BASIS, 00012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 00013 * See the License for the specific language governing permissions and 00014 * limitations under the License. 00015 */ 00016 /** 00017 * @file apr_buckets.h 00018 * @brief APR-UTIL Buckets/Bucket Brigades 00019 */ 00020 00021 #ifndef APR_BUCKETS_H 00022 #define APR_BUCKETS_H 00023 00024 #if defined(APR_BUCKET_DEBUG) && !defined(APR_RING_DEBUG) 00025 #define APR_RING_DEBUG 00026 #endif 00027 00028 #include "apu.h" 00029 #include "apr_network_io.h" 00030 #include "apr_file_io.h" 00031 #include "apr_general.h" 00032 #include "apr_mmap.h" 00033 #include "apr_errno.h" 00034 #include "apr_ring.h" 00035 #include "apr.h" 00036 #if APR_HAVE_SYS_UIO_H 00037 #include <sys/uio.h> /* for struct iovec */ 00038 #endif 00039 #if APR_HAVE_STDARG_H 00040 #include <stdarg.h> 00041 #endif 00042 00043 #ifdef __cplusplus 00044 extern "C" { 00045 #endif 00046 00047 /** 00048 * @defgroup APR_Util_Bucket_Brigades Bucket Brigades 00049 * @ingroup APR_Util 00050 * @{ 00051 */ 00052 00053 /** default bucket buffer size - 8KB minus room for memory allocator headers */ 00054 #define APR_BUCKET_BUFF_SIZE 8000 00055 00056 /** Determines how a bucket or brigade should be read */ 00057 typedef enum { 00058 APR_BLOCK_READ, /**< block until data becomes available */ 00059 APR_NONBLOCK_READ /**< return immediately if no data is available */ 00060 } apr_read_type_e; 00061 00062 /** 00063 * The one-sentence buzzword-laden overview: Bucket brigades represent 00064 * a complex data stream that can be passed through a layered IO 00065 * system without unnecessary copying. A longer overview follows... 00066 * 00067 * A bucket brigade is a doubly linked list (ring) of buckets, so we 00068 * aren't limited to inserting at the front and removing at the end. 00069 * Buckets are only passed around as members of a brigade, although 00070 * singleton buckets can occur for short periods of time. 00071 * 00072 * Buckets are data stores of various types. They can refer to data in 00073 * memory, or part of a file or mmap area, or the output of a process, 00074 * etc. Buckets also have some type-dependent accessor functions: 00075 * read, split, copy, setaside, and destroy. 00076 * 00077 * read returns the address and size of the data in the bucket. If the 00078 * data isn't in memory then it is read in and the bucket changes type 00079 * so that it can refer to the new location of the data. If all the 00080 * data doesn't fit in the bucket then a new bucket is inserted into 00081 * the brigade to hold the rest of it. 00082 * 00083 * split divides the data in a bucket into two regions. After a split 00084 * the original bucket refers to the first part of the data and a new 00085 * bucket inserted into the brigade after the original bucket refers 00086 * to the second part of the data. Reference counts are maintained as 00087 * necessary. 00088 * 00089 * setaside ensures that the data in the bucket has a long enough 00090 * lifetime. Sometimes it is convenient to create a bucket referring 00091 * to data on the stack in the expectation that it will be consumed 00092 * (output to the network) before the stack is unwound. If that 00093 * expectation turns out not to be valid, the setaside function is 00094 * called to move the data somewhere safer. 00095 * 00096 * copy makes a duplicate of the bucket structure as long as it's 00097 * possible to have multiple references to a single copy of the 00098 * data itself. Not all bucket types can be copied. 00099 * 00100 * destroy maintains the reference counts on the resources used by a 00101 * bucket and frees them if necessary. 00102 * 00103 * Note: all of the above functions have wrapper macros (apr_bucket_read(), 00104 * apr_bucket_destroy(), etc), and those macros should be used rather 00105 * than using the function pointers directly. 00106 * 00107 * To write a bucket brigade, they are first made into an iovec, so that we 00108 * don't write too little data at one time. Currently we ignore compacting the 00109 * buckets into as few buckets as possible, but if we really want good 00110 * performance, then we need to compact the buckets before we convert to an 00111 * iovec, or possibly while we are converting to an iovec. 00112 */ 00113 00114 /* 00115 * Forward declaration of the main types. 00116 */ 00117 00118 /** @see apr_bucket_brigade */ 00119 typedef struct apr_bucket_brigade apr_bucket_brigade; 00120 /** @see apr_bucket */ 00121 typedef struct apr_bucket apr_bucket; 00122 /** @see apr_bucket_alloc_t */ 00123 typedef struct apr_bucket_alloc_t apr_bucket_alloc_t; 00124 00125 /** @see apr_bucket_type_t */ 00126 typedef struct apr_bucket_type_t apr_bucket_type_t; 00127 00128 /** 00129 * Basic bucket type 00130 */ 00131 struct apr_bucket_type_t { 00132 /** 00133 * The name of the bucket type 00134 */ 00135 const char *name; 00136 /** 00137 * The number of functions this bucket understands. Can not be less than 00138 * five. 00139 */ 00140 int num_func; 00141 /** 00142 * Whether the bucket contains metadata (ie, information that 00143 * describes the regular contents of the brigade). The metadata 00144 * is not returned by apr_bucket_read() and is not indicated by 00145 * the ->length of the apr_bucket itself. In other words, an 00146 * empty bucket is safe to arbitrarily remove if and only if it 00147 * contains no metadata. In this sense, "data" is just raw bytes 00148 * that are the "content" of the brigade and "metadata" describes 00149 * that data but is not a proper part of it. 00150 */ 00151 enum { 00152 /** This bucket type represents actual data to send to the client. */ 00153 APR_BUCKET_DATA = 0, 00154 /** This bucket type represents metadata. */ 00155 APR_BUCKET_METADATA = 1 00156 } is_metadata; 00157 /** 00158 * Free the private data and any resources used by the bucket (if they 00159 * aren't shared with another bucket). This function is required to be 00160 * implemented for all bucket types, though it might be a no-op on some 00161 * of them (namely ones that never allocate any private data structures). 00162 * @param data The private data pointer from the bucket to be destroyed 00163 */ 00164 void (*destroy)(void *data); 00165 00166 /** 00167 * Read the data from the bucket. This is required to be implemented 00168 * for all bucket types. 00169 * @param b The bucket to read from 00170 * @param str A place to store the data read. Allocation should only be 00171 * done if absolutely necessary. 00172 * @param len The amount of data read. 00173 * @param block Should this read function block if there is more data that 00174 * cannot be read immediately. 00175 */ 00176 apr_status_t (*read)(apr_bucket *b, const char **str, apr_size_t *len, 00177 apr_read_type_e block); 00178 00179 /** 00180 * Make it possible to set aside the data for at least as long as the 00181 * given pool. Buckets containing data that could potentially die before 00182 * this pool (e.g. the data resides on the stack, in a child pool of 00183 * the given pool, or in a disjoint pool) must somehow copy, shift, or 00184 * transform the data to have the proper lifetime. 00185 * @param e The bucket to convert 00186 * @remark Some bucket types contain data that will always outlive the 00187 * bucket itself. For example no data (EOS and FLUSH), or the data 00188 * resides in global, constant memory (IMMORTAL), or the data is on 00189 * the heap (HEAP). For these buckets, apr_bucket_setaside_noop can 00190 * be used. 00191 */ 00192 apr_status_t (*setaside)(apr_bucket *e, apr_pool_t *pool); 00193 00194 /** 00195 * Split one bucket in two at the specified position by duplicating 00196 * the bucket structure (not the data) and modifying any necessary 00197 * start/end/offset information. If it's not possible to do this 00198 * for the bucket type (perhaps the length of the data is indeterminate, 00199 * as with pipe and socket buckets), then APR_ENOTIMPL is returned. 00200 * @param e The bucket to split 00201 * @param point The offset of the first byte in the new bucket 00202 */ 00203 apr_status_t (*split)(apr_bucket *e, apr_size_t point); 00204 00205 /** 00206 * Copy the bucket structure (not the data), assuming that this is 00207 * possible for the bucket type. If it's not, APR_ENOTIMPL is returned. 00208 * @param e The bucket to copy 00209 * @param c Returns a pointer to the new bucket 00210 */ 00211 apr_status_t (*copy)(apr_bucket *e, apr_bucket **c); 00212 00213 }; 00214 00215 /** 00216 * apr_bucket structures are allocated on the malloc() heap and 00217 * their lifetime is controlled by the parent apr_bucket_brigade 00218 * structure. Buckets can move from one brigade to another e.g. by 00219 * calling APR_BRIGADE_CONCAT(). In general the data in a bucket has 00220 * the same lifetime as the bucket and is freed when the bucket is 00221 * destroyed; if the data is shared by more than one bucket (e.g. 00222 * after a split) the data is freed when the last bucket goes away. 00223 */ 00224 struct apr_bucket { 00225 /** Links to the rest of the brigade */ 00226 APR_RING_ENTRY(apr_bucket) link; 00227 /** The type of bucket. */ 00228 const apr_bucket_type_t *type; 00229 /** The length of the data in the bucket. This could have been implemented 00230 * with a function, but this is an optimization, because the most 00231 * common thing to do will be to get the length. If the length is unknown, 00232 * the value of this field will be (apr_size_t)(-1). 00233 */ 00234 apr_size_t length; 00235 /** The start of the data in the bucket relative to the private base 00236 * pointer. The vast majority of bucket types allow a fixed block of 00237 * data to be referenced by multiple buckets, each bucket pointing to 00238 * a different segment of the data. That segment starts at base+start 00239 * and ends at base+start+length. 00240 * If the length == (apr_size_t)(-1), then start == -1. 00241 */ 00242 apr_off_t start; 00243 /** type-dependent data hangs off this pointer */ 00244 void *data; 00245 /** 00246 * Pointer to function used to free the bucket. This function should 00247 * always be defined and it should be consistent with the memory 00248 * function used to allocate the bucket. For example, if malloc() is 00249 * used to allocate the bucket, this pointer should point to free(). 00250 * @param e Pointer to the bucket being freed 00251 */ 00252 void (*free)(void *e); 00253 /** The freelist from which this bucket was allocated */ 00254 apr_bucket_alloc_t *list; 00255 }; 00256 00257 /** A list of buckets */ 00258 struct apr_bucket_brigade { 00259 /** The pool to associate the brigade with. The data is not allocated out 00260 * of the pool, but a cleanup is registered with this pool. If the 00261 * brigade is destroyed by some mechanism other than pool destruction, 00262 * the destroying function is responsible for killing the cleanup. 00263 */ 00264 apr_pool_t *p; 00265 /** The buckets in the brigade are on this list. */ 00266 /* 00267 * The apr_bucket_list structure doesn't actually need a name tag 00268 * because it has no existence independent of struct apr_bucket_brigade; 00269 * the ring macros are designed so that you can leave the name tag 00270 * argument empty in this situation but apparently the Windows compiler 00271 * doesn't like that. 00272 */ 00273 APR_RING_HEAD(apr_bucket_list, apr_bucket) list; 00274 /** The freelist from which this bucket was allocated */ 00275 apr_bucket_alloc_t *bucket_alloc; 00276 }; 00277 00278 00279 /** 00280 * Function called when a brigade should be flushed 00281 */ 00282 typedef apr_status_t (*apr_brigade_flush)(apr_bucket_brigade *bb, void *ctx); 00283 00284 /* 00285 * define APR_BUCKET_DEBUG if you want your brigades to be checked for 00286 * validity at every possible instant. this will slow your code down 00287 * substantially but is a very useful debugging tool. 00288 */ 00289 #ifdef APR_BUCKET_DEBUG 00290 00291 #define APR_BRIGADE_CHECK_CONSISTENCY(b) \ 00292 APR_RING_CHECK_CONSISTENCY(&(b)->list, apr_bucket, link) 00293 00294 #define APR_BUCKET_CHECK_CONSISTENCY(e) \ 00295 APR_RING_CHECK_ELEM_CONSISTENCY((e), apr_bucket, link) 00296 00297 #else 00298 /** 00299 * checks the ring pointers in a bucket brigade for consistency. an 00300 * abort() will be triggered if any inconsistencies are found. 00301 * note: this is a no-op unless APR_BUCKET_DEBUG is defined. 00302 * @param b The brigade 00303 */ 00304 #define APR_BRIGADE_CHECK_CONSISTENCY(b) 00305 /** 00306 * checks the brigade a bucket is in for ring consistency. an 00307 * abort() will be triggered if any inconsistencies are found. 00308 * note: this is a no-op unless APR_BUCKET_DEBUG is defined. 00309 * @param e The bucket 00310 */ 00311 #define APR_BUCKET_CHECK_CONSISTENCY(e) 00312 #endif 00313 00314 00315 /** 00316 * Wrappers around the RING macros to reduce the verbosity of the code 00317 * that handles bucket brigades. 00318 */ 00319 /** 00320 * The magic pointer value that indicates the head of the brigade 00321 * @remark This is used to find the beginning and end of the brigade, eg: 00322 * <pre> 00323 * while (e != APR_BRIGADE_SENTINEL(b)) { 00324 * ... 00325 * e = APR_BUCKET_NEXT(e); 00326 * } 00327 * </pre> 00328 * @param b The brigade 00329 * @return The magic pointer value 00330 */ 00331 #define APR_BRIGADE_SENTINEL(b) APR_RING_SENTINEL(&(b)->list, apr_bucket, link) 00332 00333 /** 00334 * Determine if the bucket brigade is empty 00335 * @param b The brigade to check 00336 * @return true or false 00337 */ 00338 #define APR_BRIGADE_EMPTY(b) APR_RING_EMPTY(&(b)->list, apr_bucket, link) 00339 00340 /** 00341 * Return the first bucket in a brigade 00342 * @param b The brigade to query 00343 * @return The first bucket in the brigade 00344 */ 00345 #define APR_BRIGADE_FIRST(b) APR_RING_FIRST(&(b)->list) 00346 /** 00347 * Return the last bucket in a brigade 00348 * @param b The brigade to query 00349 * @return The last bucket in the brigade 00350 */ 00351 #define APR_BRIGADE_LAST(b) APR_RING_LAST(&(b)->list) 00352 00353 /** 00354 * Insert a list of buckets at the front of a brigade 00355 * @param b The brigade to add to 00356 * @param e The first bucket in a list of buckets to insert 00357 */ 00358 #define APR_BRIGADE_INSERT_HEAD(b, e) do { \ 00359 apr_bucket *ap__b = (e); \ 00360 APR_RING_INSERT_HEAD(&(b)->list, ap__b, apr_bucket, link); \ 00361 APR_BRIGADE_CHECK_CONSISTENCY((b)); \ 00362 } while (0) 00363 00364 /** 00365 * Insert a list of buckets at the end of a brigade 00366 * @param b The brigade to add to 00367 * @param e The first bucket in a list of buckets to insert 00368 */ 00369 #define APR_BRIGADE_INSERT_TAIL(b, e) do { \ 00370 apr_bucket *ap__b = (e); \ 00371 APR_RING_INSERT_TAIL(&(b)->list, ap__b, apr_bucket, link); \ 00372 APR_BRIGADE_CHECK_CONSISTENCY((b)); \ 00373 } while (0) 00374 00375 /** 00376 * Concatenate brigade b onto the end of brigade a, leaving brigade b empty 00377 * @param a The first brigade 00378 * @param b The second brigade 00379 */ 00380 #define APR_BRIGADE_CONCAT(a, b) do { \ 00381 APR_RING_CONCAT(&(a)->list, &(b)->list, apr_bucket, link); \ 00382 APR_BRIGADE_CHECK_CONSISTENCY((a)); \ 00383 } while (0) 00384 00385 /** 00386 * Prepend brigade b onto the beginning of brigade a, leaving brigade b empty 00387 * @param a The first brigade 00388 * @param b The second brigade 00389 */ 00390 #define APR_BRIGADE_PREPEND(a, b) do { \ 00391 APR_RING_PREPEND(&(a)->list, &(b)->list, apr_bucket, link); \ 00392 APR_BRIGADE_CHECK_CONSISTENCY((a)); \ 00393 } while (0) 00394 00395 /** 00396 * Insert a list of buckets before a specified bucket 00397 * @param a The bucket to insert before 00398 * @param b The buckets to insert 00399 */ 00400 #define APR_BUCKET_INSERT_BEFORE(a, b) do { \ 00401 apr_bucket *ap__a = (a), *ap__b = (b); \ 00402 APR_RING_INSERT_BEFORE(ap__a, ap__b, link); \ 00403 APR_BUCKET_CHECK_CONSISTENCY(ap__a); \ 00404 } while (0) 00405 00406 /** 00407 * Insert a list of buckets after a specified bucket 00408 * @param a The bucket to insert after 00409 * @param b The buckets to insert 00410 */ 00411 #define APR_BUCKET_INSERT_AFTER(a, b) do { \ 00412 apr_bucket *ap__a = (a), *ap__b = (b); \ 00413 APR_RING_INSERT_AFTER(ap__a, ap__b, link); \ 00414 APR_BUCKET_CHECK_CONSISTENCY(ap__a); \ 00415 } while (0) 00416 00417 /** 00418 * Get the next bucket in the list 00419 * @param e The current bucket 00420 * @return The next bucket 00421 */ 00422 #define APR_BUCKET_NEXT(e) APR_RING_NEXT((e), link) 00423 /** 00424 * Get the previous bucket in the list 00425 * @param e The current bucket 00426 * @return The previous bucket 00427 */ 00428 #define APR_BUCKET_PREV(e) APR_RING_PREV((e), link) 00429 00430 /** 00431 * Remove a bucket from its bucket brigade 00432 * @param e The bucket to remove 00433 */ 00434 #define APR_BUCKET_REMOVE(e) APR_RING_REMOVE((e), link) 00435 00436 /** 00437 * Initialize a new bucket's prev/next pointers 00438 * @param e The bucket to initialize 00439 */ 00440 #define APR_BUCKET_INIT(e) APR_RING_ELEM_INIT((e), link) 00441 00442 /** 00443 * Determine if a bucket contains metadata. An empty bucket is 00444 * safe to arbitrarily remove if and only if this is false. 00445 * @param e The bucket to inspect 00446 * @return true or false 00447 */ 00448 #define APR_BUCKET_IS_METADATA(e) ((e)->type->is_metadata) 00449 00450 /** 00451 * Determine if a bucket is a FLUSH bucket 00452 * @param e The bucket to inspect 00453 * @return true or false 00454 */ 00455 #define APR_BUCKET_IS_FLUSH(e) ((e)->type == &apr_bucket_type_flush) 00456 /** 00457 * Determine if a bucket is an EOS bucket 00458 * @param e The bucket to inspect 00459 * @return true or false 00460 */ 00461 #define APR_BUCKET_IS_EOS(e) ((e)->type == &apr_bucket_type_eos) 00462 /** 00463 * Determine if a bucket is a FILE bucket 00464 * @param e The bucket to inspect 00465 * @return true or false 00466 */ 00467 #define APR_BUCKET_IS_FILE(e) ((e)->type == &apr_bucket_type_file) 00468 /** 00469 * Determine if a bucket is a PIPE bucket 00470 * @param e The bucket to inspect 00471 * @return true or false 00472 */ 00473 #define APR_BUCKET_IS_PIPE(e) ((e)->type == &apr_bucket_type_pipe) 00474 /** 00475 * Determine if a bucket is a SOCKET bucket 00476 * @param e The bucket to inspect 00477 * @return true or false 00478 */ 00479 #define APR_BUCKET_IS_SOCKET(e) ((e)->type == &apr_bucket_type_socket) 00480 /** 00481 * Determine if a bucket is a HEAP bucket 00482 * @param e The bucket to inspect 00483 * @return true or false 00484 */ 00485 #define APR_BUCKET_IS_HEAP(e) ((e)->type == &apr_bucket_type_heap) 00486 /** 00487 * Determine if a bucket is a TRANSIENT bucket 00488 * @param e The bucket to inspect 00489 * @return true or false 00490 */ 00491 #define APR_BUCKET_IS_TRANSIENT(e) ((e)->type == &apr_bucket_type_transient) 00492 /** 00493 * Determine if a bucket is a IMMORTAL bucket 00494 * @param e The bucket to inspect 00495 * @return true or false 00496 */ 00497 #define APR_BUCKET_IS_IMMORTAL(e) ((e)->type == &apr_bucket_type_immortal) 00498 #if APR_HAS_MMAP 00499 /** 00500 * Determine if a bucket is a MMAP bucket 00501 * @param e The bucket to inspect 00502 * @return true or false 00503 */ 00504 #define APR_BUCKET_IS_MMAP(e) ((e)->type == &apr_bucket_type_mmap) 00505 #endif 00506 /** 00507 * Determine if a bucket is a POOL bucket 00508 * @param e The bucket to inspect 00509 * @return true or false 00510 */ 00511 #define APR_BUCKET_IS_POOL(e) ((e)->type == &apr_bucket_type_pool) 00512 00513 /* 00514 * General-purpose reference counting for the various bucket types. 00515 * 00516 * Any bucket type that keeps track of the resources it uses (i.e. 00517 * most of them except for IMMORTAL, TRANSIENT, and EOS) needs to 00518 * attach a reference count to the resource so that it can be freed 00519 * when the last bucket that uses it goes away. Resource-sharing may 00520 * occur because of bucket splits or buckets that refer to globally 00521 * cached data. */ 00522 00523 /** @see apr_bucket_refcount */ 00524 typedef struct apr_bucket_refcount apr_bucket_refcount; 00525 /** 00526 * The structure used to manage the shared resource must start with an 00527 * apr_bucket_refcount which is updated by the general-purpose refcount 00528 * code. A pointer to the bucket-type-dependent private data structure 00529 * can be cast to a pointer to an apr_bucket_refcount and vice versa. 00530 */ 00531 struct apr_bucket_refcount { 00532 /** The number of references to this bucket */ 00533 int refcount; 00534 }; 00535 00536 /* ***** Reference-counted bucket types ***** */ 00537 00538 /** @see apr_bucket_heap */ 00539 typedef struct apr_bucket_heap apr_bucket_heap; 00540 /** 00541 * A bucket referring to data allocated off the heap. 00542 */ 00543 struct apr_bucket_heap { 00544 /** Number of buckets using this memory */ 00545 apr_bucket_refcount refcount; 00546 /** The start of the data actually allocated. This should never be 00547 * modified, it is only used to free the bucket. 00548 */ 00549 char *base; 00550 /** how much memory was allocated */ 00551 apr_size_t alloc_len; 00552 /** function to use to delete the data */ 00553 void (*free_func)(void *data); 00554 }; 00555 00556 /** @see apr_bucket_pool */ 00557 typedef struct apr_bucket_pool apr_bucket_pool; 00558 /** 00559 * A bucket referring to data allocated from a pool 00560 */ 00561 struct apr_bucket_pool { 00562 /** The pool bucket must be able to be easily morphed to a heap 00563 * bucket if the pool gets cleaned up before all references are 00564 * destroyed. This apr_bucket_heap structure is populated automatically 00565 * when the pool gets cleaned up, and subsequent calls to pool_read() 00566 * will result in the apr_bucket in question being morphed into a 00567 * regular heap bucket. (To avoid having to do many extra refcount 00568 * manipulations and b->data manipulations, the apr_bucket_pool 00569 * struct actually *contains* the apr_bucket_heap struct that it 00570 * will become as its first element; the two share their 00571 * apr_bucket_refcount members.) 00572 */ 00573 apr_bucket_heap heap; 00574 /** The block of data actually allocated from the pool. 00575 * Segments of this block are referenced by adjusting 00576 * the start and length of the apr_bucket accordingly. 00577 * This will be NULL after the pool gets cleaned up. 00578 */ 00579 const char *base; 00580 /** The pool the data was allocated from. When the pool 00581 * is cleaned up, this gets set to NULL as an indicator 00582 * to pool_read() that the data is now on the heap and 00583 * so it should morph the bucket into a regular heap 00584 * bucket before continuing. 00585 */ 00586 apr_pool_t *pool; 00587 /** The freelist this structure was allocated from, which is 00588 * needed in the cleanup phase in order to allocate space on the heap 00589 */ 00590 apr_bucket_alloc_t *list; 00591 }; 00592 00593 #if APR_HAS_MMAP 00594 /** @see apr_bucket_mmap */ 00595 typedef struct apr_bucket_mmap apr_bucket_mmap; 00596 /** 00597 * A bucket referring to an mmap()ed file 00598 */ 00599 struct apr_bucket_mmap { 00600 /** Number of buckets using this memory */ 00601 apr_bucket_refcount refcount; 00602 /** The mmap this sub_bucket refers to */ 00603 apr_mmap_t *mmap; 00604 }; 00605 #endif 00606 00607 /** @see apr_bucket_file */ 00608 typedef struct apr_bucket_file apr_bucket_file; 00609 /** 00610 * A bucket referring to an file 00611 */ 00612 struct apr_bucket_file { 00613 /** Number of buckets using this memory */ 00614 apr_bucket_refcount refcount; 00615 /** The file this bucket refers to */ 00616 apr_file_t *fd; 00617 /** The pool into which any needed structures should 00618 * be created while reading from this file bucket */ 00619 apr_pool_t *readpool; 00620 #if APR_HAS_MMAP 00621 /** Whether this bucket should be memory-mapped if 00622 * a caller tries to read from it */ 00623 int can_mmap; 00624 #endif /* APR_HAS_MMAP */ 00625 }; 00626 00627 /** @see apr_bucket_structs */ 00628 typedef union apr_bucket_structs apr_bucket_structs; 00629 /** 00630 * A union of all bucket structures so we know what 00631 * the max size is. 00632 */ 00633 union apr_bucket_structs { 00634 apr_bucket b; /**< Bucket */ 00635 apr_bucket_heap heap; /**< Heap */ 00636 apr_bucket_pool pool; /**< Pool */ 00637 #if APR_HAS_MMAP 00638 apr_bucket_mmap mmap; /**< MMap */ 00639 #endif 00640 apr_bucket_file file; /**< File */ 00641 }; 00642 00643 /** 00644 * The amount that apr_bucket_alloc() should allocate in the common case. 00645 * Note: this is twice as big as apr_bucket_structs to allow breathing 00646 * room for third-party bucket types. 00647 */ 00648 #define APR_BUCKET_ALLOC_SIZE APR_ALIGN_DEFAULT(2*sizeof(apr_bucket_structs)) 00649 00650 /* ***** Bucket Brigade Functions ***** */ 00651 /** 00652 * Create a new bucket brigade. The bucket brigade is originally empty. 00653 * @param p The pool to associate with the brigade. Data is not allocated out 00654 * of the pool, but a cleanup is registered. 00655 * @param list The bucket allocator to use 00656 * @return The empty bucket brigade 00657 */ 00658 APU_DECLARE(apr_bucket_brigade *) apr_brigade_create(apr_pool_t *p, 00659 apr_bucket_alloc_t *list); 00660 00661 /** 00662 * destroy an entire bucket brigade. This includes destroying all of the 00663 * buckets within the bucket brigade's bucket list. 00664 * @param b The bucket brigade to destroy 00665 */ 00666 APU_DECLARE(apr_status_t) apr_brigade_destroy(apr_bucket_brigade *b); 00667 00668 /** 00669 * empty out an entire bucket brigade. This includes destroying all of the 00670 * buckets within the bucket brigade's bucket list. This is similar to 00671 * apr_brigade_destroy(), except that it does not deregister the brigade's 00672 * pool cleanup function. 00673 * @param data The bucket brigade to clean up 00674 * @remark Generally, you should use apr_brigade_destroy(). This function 00675 * can be useful in situations where you have a single brigade that 00676 * you wish to reuse many times by destroying all of the buckets in 00677 * the brigade and putting new buckets into it later. 00678 */ 00679 APU_DECLARE(apr_status_t) apr_brigade_cleanup(void *data); 00680 00681 /** 00682 * Move the buckets from the tail end of the existing brigade @param b into 00683 * the brigade @param a. If @param a is NULL a new brigade is created. Buckets 00684 * from @param e to the last bucket (inclusively) of brigade @param b are moved 00685 * from @param b to the returned brigade @param a. 00686 * @param b The brigade to split 00687 * @param e The first bucket to move 00688 * @param a The brigade which should be used for the result or NULL if 00689 * a new brigade should be created. 00690 * @return The brigade supplied in @param a or a new one if @param a was NULL. 00691 * @warning Note that this function allocates a new brigade if @param a is 00692 * NULL so memory consumption should be carefully considered. 00693 */ 00694 APU_DECLARE(apr_bucket_brigade *) apr_brigade_split_ex(apr_bucket_brigade *b, 00695 apr_bucket *e, 00696 apr_bucket_brigade *a); 00697 00698 /** 00699 * Create a new bucket brigade and move the buckets from the tail end 00700 * of an existing brigade into the new brigade. Buckets from 00701 * @param e to the last bucket (inclusively) of brigade @param b 00702 * are moved from @param b to the returned brigade. 00703 * @param b The brigade to split 00704 * @param e The first bucket to move 00705 * @return The new brigade 00706 * @warning Note that this function always allocates a new brigade 00707 * so memory consumption should be carefully considered. 00708 */ 00709 APU_DECLARE(apr_bucket_brigade *) apr_brigade_split(apr_bucket_brigade *b, 00710 apr_bucket *e); 00711 00712 /** 00713 * Partition a bucket brigade at a given offset (in bytes from the start of 00714 * the brigade). This is useful whenever a filter wants to use known ranges 00715 * of bytes from the brigade; the ranges can even overlap. 00716 * @param b The brigade to partition 00717 * @param point The offset at which to partition the brigade 00718 * @param after_point Returns a pointer to the first bucket after the partition 00719 * @return APR_SUCCESS on success, APR_INCOMPLETE if the contents of the 00720 * brigade were shorter than @a point, or an error code. 00721 * @remark if APR_INCOMPLETE is returned, @a after_point will be set to 00722 * the brigade sentinel. 00723 */ 00724 APU_DECLARE(apr_status_t) apr_brigade_partition(apr_bucket_brigade *b, 00725 apr_off_t point, 00726 apr_bucket **after_point); 00727 00728 /** 00729 * Return the total length of the brigade. 00730 * @param bb The brigade to compute the length of 00731 * @param read_all Read unknown-length buckets to force a size 00732 * @param length Returns the length of the brigade (up to the end, or up 00733 * to a bucket read error), or -1 if the brigade has buckets 00734 * of indeterminate length and read_all is 0. 00735 */ 00736 APU_DECLARE(apr_status_t) apr_brigade_length(apr_bucket_brigade *bb, 00737 int read_all, 00738 apr_off_t *length); 00739 00740 /** 00741 * Take a bucket brigade and store the data in a flat char* 00742 * @param bb The bucket brigade to create the char* from 00743 * @param c The char* to write into 00744 * @param len The maximum length of the char array. On return, it is the 00745 * actual length of the char array. 00746 */ 00747 APU_DECLARE(apr_status_t) apr_brigade_flatten(apr_bucket_brigade *bb, 00748 char *c, 00749 apr_size_t *len); 00750 00751 /** 00752 * Creates a pool-allocated string representing a flat bucket brigade 00753 * @param bb The bucket brigade to create the char array from 00754 * @param c On return, the allocated char array 00755 * @param len On return, the length of the char array. 00756 * @param pool The pool to allocate the string from. 00757 */ 00758 APU_DECLARE(apr_status_t) apr_brigade_pflatten(apr_bucket_brigade *bb, 00759 char **c, 00760 apr_size_t *len, 00761 apr_pool_t *pool); 00762 00763 /** 00764 * Split a brigade to represent one LF line. 00765 * @param bbOut The bucket brigade that will have the LF line appended to. 00766 * @param bbIn The input bucket brigade to search for a LF-line. 00767 * @param block The blocking mode to be used to split the line. 00768 * @param maxbytes The maximum bytes to read. If this many bytes are seen 00769 * without a LF, the brigade will contain a partial line. 00770 */ 00771 APU_DECLARE(apr_status_t) apr_brigade_split_line(apr_bucket_brigade *bbOut, 00772 apr_bucket_brigade *bbIn, 00773 apr_read_type_e block, 00774 apr_off_t maxbytes); 00775 00776 /** 00777 * create an iovec of the elements in a bucket_brigade... return number 00778 * of elements used. This is useful for writing to a file or to the 00779 * network efficiently. 00780 * @param b The bucket brigade to create the iovec from 00781 * @param vec The iovec to create 00782 * @param nvec The number of elements in the iovec. On return, it is the 00783 * number of iovec elements actually filled out. 00784 */ 00785 APU_DECLARE(apr_status_t) apr_brigade_to_iovec(apr_bucket_brigade *b, 00786 struct iovec *vec, int *nvec); 00787 00788 /** 00789 * This function writes a list of strings into a bucket brigade. 00790 * @param b The bucket brigade to add to 00791 * @param flush The flush function to use if the brigade is full 00792 * @param ctx The structure to pass to the flush function 00793 * @param va A list of strings to add 00794 * @return APR_SUCCESS or error code. 00795 */ 00796 APU_DECLARE(apr_status_t) apr_brigade_vputstrs(apr_bucket_brigade *b, 00797 apr_brigade_flush flush, 00798 void *ctx, 00799 va_list va); 00800 00801 /** 00802 * This function writes a string into a bucket brigade. 00803 * @param b The bucket brigade to add to 00804 * @param flush The flush function to use if the brigade is full 00805 * @param ctx The structure to pass to the flush function 00806 * @param str The string to add 00807 * @param nbyte The number of bytes to write 00808 * @return APR_SUCCESS or error code 00809 */ 00810 APU_DECLARE(apr_status_t) apr_brigade_write(apr_bucket_brigade *b, 00811 apr_brigade_flush flush, void *ctx, 00812 const char *str, apr_size_t nbyte); 00813 00814 /** 00815 * This function writes multiple strings into a bucket brigade. 00816 * @param b The bucket brigade to add to 00817 * @param flush The flush function to use if the brigade is full 00818 * @param ctx The structure to pass to the flush function 00819 * @param vec The strings to add (address plus length for each) 00820 * @param nvec The number of entries in iovec 00821 * @return APR_SUCCESS or error code 00822 */ 00823 APU_DECLARE(apr_status_t) apr_brigade_writev(apr_bucket_brigade *b, 00824 apr_brigade_flush flush, 00825 void *ctx, 00826 const struct iovec *vec, 00827 apr_size_t nvec); 00828 00829 /** 00830 * This function writes a string into a bucket brigade. 00831 * @param bb The bucket brigade to add to 00832 * @param flush The flush function to use if the brigade is full 00833 * @param ctx The structure to pass to the flush function 00834 * @param str The string to add 00835 * @return APR_SUCCESS or error code 00836 */ 00837 APU_DECLARE(apr_status_t) apr_brigade_puts(apr_bucket_brigade *bb, 00838 apr_brigade_flush flush, void *ctx, 00839 const char *str); 00840 00841 /** 00842 * This function writes a character into a bucket brigade. 00843 * @param b The bucket brigade to add to 00844 * @param flush The flush function to use if the brigade is full 00845 * @param ctx The structure to pass to the flush function 00846 * @param c The character to add 00847 * @return APR_SUCCESS or error code 00848 */ 00849 APU_DECLARE(apr_status_t) apr_brigade_putc(apr_bucket_brigade *b, 00850 apr_brigade_flush flush, void *ctx, 00851 const char c); 00852 00853 /** 00854 * This function writes an unspecified number of strings into a bucket brigade. 00855 * @param b The bucket brigade to add to 00856 * @param flush The flush function to use if the brigade is full 00857 * @param ctx The structure to pass to the flush function 00858 * @param ... The strings to add 00859 * @return APR_SUCCESS or error code 00860 */ 00861 APU_DECLARE_NONSTD(apr_status_t) apr_brigade_putstrs(apr_bucket_brigade *b, 00862 apr_brigade_flush flush, 00863 void *ctx, ...); 00864 00865 /** 00866 * Evaluate a printf and put the resulting string at the end 00867 * of the bucket brigade. 00868 * @param b The brigade to write to 00869 * @param flush The flush function to use if the brigade is full 00870 * @param ctx The structure to pass to the flush function 00871 * @param fmt The format of the string to write 00872 * @param ... The arguments to fill out the format 00873 * @return APR_SUCCESS or error code 00874 */ 00875 APU_DECLARE_NONSTD(apr_status_t) apr_brigade_printf(apr_bucket_brigade *b, 00876 apr_brigade_flush flush, 00877 void *ctx, 00878 const char *fmt, ...) 00879 __attribute__((format(printf,4,5))); 00880 00881 /** 00882 * Evaluate a printf and put the resulting string at the end 00883 * of the bucket brigade. 00884 * @param b The brigade to write to 00885 * @param flush The flush function to use if the brigade is full 00886 * @param ctx The structure to pass to the flush function 00887 * @param fmt The format of the string to write 00888 * @param va The arguments to fill out the format 00889 * @return APR_SUCCESS or error code 00890 */ 00891 APU_DECLARE(apr_status_t) apr_brigade_vprintf(apr_bucket_brigade *b, 00892 apr_brigade_flush flush, 00893 void *ctx, 00894 const char *fmt, va_list va); 00895 00896 /** 00897 * Utility function to insert a file (or a segment of a file) onto the 00898 * end of the brigade. The file is split into multiple buckets if it 00899 * is larger than the maximum size which can be represented by a 00900 * single bucket. 00901 * @param bb the brigade to insert into 00902 * @param f the file to insert 00903 * @param start the offset of the start of the segment 00904 * @param len the length of the segment of the file to insert 00905 * @param p pool from which file buckets are allocated 00906 * @return the last bucket inserted 00907 */ 00908 APU_DECLARE(apr_bucket *) apr_brigade_insert_file(apr_bucket_brigade *bb, 00909 apr_file_t *f, 00910 apr_off_t start, 00911 apr_off_t len, 00912 apr_pool_t *p); 00913 00914 00915 00916 /* ***** Bucket freelist functions ***** */ 00917 /** 00918 * Create a bucket allocator. 00919 * @param p This pool's underlying apr_allocator_t is used to allocate memory 00920 * for the bucket allocator. When the pool is destroyed, the bucket 00921 * allocator's cleanup routine will free all memory that has been 00922 * allocated from it. 00923 * @remark The reason the allocator gets its memory from the pool's 00924 * apr_allocator_t rather than from the pool itself is because 00925 * the bucket allocator will free large memory blocks back to the 00926 * allocator when it's done with them, thereby preventing memory 00927 * footprint growth that would occur if we allocated from the pool. 00928 * @warning The allocator must never be used by more than one thread at a time. 00929 */ 00930 APU_DECLARE_NONSTD(apr_bucket_alloc_t *) apr_bucket_alloc_create(apr_pool_t *p); 00931 00932 /** 00933 * Create a bucket allocator. 00934 * @param allocator This apr_allocator_t is used to allocate both the bucket 00935 * allocator and all memory handed out by the bucket allocator. The 00936 * caller is responsible for destroying the bucket allocator and the 00937 * apr_allocator_t -- no automatic cleanups will happen. 00938 * @warning The allocator must never be used by more than one thread at a time. 00939 */ 00940 APU_DECLARE_NONSTD(apr_bucket_alloc_t *) apr_bucket_alloc_create_ex(apr_allocator_t *allocator); 00941 00942 /** 00943 * Destroy a bucket allocator. 00944 * @param list The allocator to be destroyed 00945 */ 00946 APU_DECLARE_NONSTD(void) apr_bucket_alloc_destroy(apr_bucket_alloc_t *list); 00947 00948 /** 00949 * Allocate memory for use by the buckets. 00950 * @param size The amount to allocate. 00951 * @param list The allocator from which to allocate the memory. 00952 */ 00953 APU_DECLARE_NONSTD(void *) apr_bucket_alloc(apr_size_t size, apr_bucket_alloc_t *list); 00954 00955 /** 00956 * Free memory previously allocated with apr_bucket_alloc(). 00957 * @param block The block of memory to be freed. 00958 */ 00959 APU_DECLARE_NONSTD(void) apr_bucket_free(void *block); 00960 00961 00962 /* ***** Bucket Functions ***** */ 00963 /** 00964 * Free the resources used by a bucket. If multiple buckets refer to 00965 * the same resource it is freed when the last one goes away. 00966 * @see apr_bucket_delete() 00967 * @param e The bucket to destroy 00968 */ 00969 #define apr_bucket_destroy(e) do { \ 00970 (e)->type->destroy((e)->data); \ 00971 (e)->free(e); \ 00972 } while (0) 00973 00974 /** 00975 * Delete a bucket by removing it from its brigade (if any) and then 00976 * destroying it. 00977 * @remark This mainly acts as an aid in avoiding code verbosity. It is 00978 * the preferred exact equivalent to: 00979 * <pre> 00980 * APR_BUCKET_REMOVE(e); 00981 * apr_bucket_destroy(e); 00982 * </pre> 00983 * @param e The bucket to delete 00984 */ 00985 #define apr_bucket_delete(e) do { \ 00986 APR_BUCKET_REMOVE(e); \ 00987 apr_bucket_destroy(e); \ 00988 } while (0) 00989 00990 /** 00991 * Read the data from the bucket. 00992 * 00993 * If it is not practical to return all 00994 * the data in the bucket, the current bucket is split and replaced by 00995 * two buckets, the first representing the data returned in this call, 00996 * and the second representing the rest of the data as yet unread. The 00997 * original bucket will become the first bucket after this call. 00998 * 00999 * (It is assumed that the bucket is a member of a brigade when this 01000 * function is called). 01001 * @param e The bucket to read from 01002 * @param str The location to store the data in 01003 * @param len The amount of data read 01004 * @param block Whether the read function blocks 01005 */ 01006 #define apr_bucket_read(e,str,len,block) (e)->type->read(e, str, len, block) 01007 01008 /** 01009 * Setaside data so that stack data is not destroyed on returning from 01010 * the function 01011 * @param e The bucket to setaside 01012 * @param p The pool to setaside into 01013 */ 01014 #define apr_bucket_setaside(e,p) (e)->type->setaside(e,p) 01015 01016 /** 01017 * Split one bucket in two at the point provided. 01018 * 01019 * Once split, the original bucket becomes the first of the two new buckets. 01020 * 01021 * (It is assumed that the bucket is a member of a brigade when this 01022 * function is called). 01023 * @param e The bucket to split 01024 * @param point The offset to split the bucket at 01025 */ 01026 #define apr_bucket_split(e,point) (e)->type->split(e, point) 01027 01028 /** 01029 * Copy a bucket. 01030 * @param e The bucket to copy 01031 * @param c Returns a pointer to the new bucket 01032 */ 01033 #define apr_bucket_copy(e,c) (e)->type->copy(e, c) 01034 01035 /* Bucket type handling */ 01036 01037 /** 01038 * This function simply returns APR_SUCCESS to denote that the bucket does 01039 * not require anything to happen for its setaside() function. This is 01040 * appropriate for buckets that have "immortal" data -- the data will live 01041 * at least as long as the bucket. 01042 * @param data The bucket to setaside 01043 * @param pool The pool defining the desired lifetime of the bucket data 01044 * @return APR_SUCCESS 01045 */ 01046 APU_DECLARE_NONSTD(apr_status_t) apr_bucket_setaside_noop(apr_bucket *data, 01047 apr_pool_t *pool); 01048 01049 /** 01050 * A place holder function that signifies that the setaside function was not 01051 * implemented for this bucket 01052 * @param data The bucket to setaside 01053 * @param pool The pool defining the desired lifetime of the bucket data 01054 * @return APR_ENOTIMPL 01055 */ 01056 APU_DECLARE_NONSTD(apr_status_t) apr_bucket_setaside_notimpl(apr_bucket *data, 01057 apr_pool_t *pool); 01058 01059 /** 01060 * A place holder function that signifies that the split function was not 01061 * implemented for this bucket 01062 * @param data The bucket to split 01063 * @param point The location to split the bucket 01064 * @return APR_ENOTIMPL 01065 */ 01066 APU_DECLARE_NONSTD(apr_status_t) apr_bucket_split_notimpl(apr_bucket *data, 01067 apr_size_t point); 01068 01069 /** 01070 * A place holder function that signifies that the copy function was not 01071 * implemented for this bucket 01072 * @param e The bucket to copy 01073 * @param c Returns a pointer to the new bucket 01074 * @return APR_ENOTIMPL 01075 */ 01076 APU_DECLARE_NONSTD(apr_status_t) apr_bucket_copy_notimpl(apr_bucket *e, 01077 apr_bucket **c); 01078 01079 /** 01080 * A place holder function that signifies that this bucket does not need 01081 * to do anything special to be destroyed. That's only the case for buckets 01082 * that either have no data (metadata buckets) or buckets whose data pointer 01083 * points to something that's not a bucket-type-specific structure, as with 01084 * simple buckets where data points to a string and pipe buckets where data 01085 * points directly to the apr_file_t. 01086 * @param data The bucket data to destroy 01087 */ 01088 APU_DECLARE_NONSTD(void) apr_bucket_destroy_noop(void *data); 01089 01090 /** 01091 * There is no apr_bucket_destroy_notimpl, because destruction is required 01092 * to be implemented (it could be a noop, but only if that makes sense for 01093 * the bucket type) 01094 */ 01095 01096 /* There is no apr_bucket_read_notimpl, because it is a required function 01097 */ 01098 01099 01100 /* All of the bucket types implemented by the core */ 01101 /** 01102 * The flush bucket type. This signifies that all data should be flushed to 01103 * the next filter. The flush bucket should be sent with the other buckets. 01104 */ 01105 APU_DECLARE_DATA extern const apr_bucket_type_t apr_bucket_type_flush; 01106 /** 01107 * The EOS bucket type. This signifies that there will be no more data, ever. 01108 * All filters MUST send all data to the next filter when they receive a 01109 * bucket of this type 01110 */ 01111 APU_DECLARE_DATA extern const apr_bucket_type_t apr_bucket_type_eos; 01112 /** 01113 * The FILE bucket type. This bucket represents a file on disk 01114 */ 01115 APU_DECLARE_DATA extern const apr_bucket_type_t apr_bucket_type_file; 01116 /** 01117 * The HEAP bucket type. This bucket represents a data allocated from the 01118 * heap. 01119 */ 01120 APU_DECLARE_DATA extern const apr_bucket_type_t apr_bucket_type_heap; 01121 #if APR_HAS_MMAP 01122 /** 01123 * The MMAP bucket type. This bucket represents an MMAP'ed file 01124 */ 01125 APU_DECLARE_DATA extern const apr_bucket_type_t apr_bucket_type_mmap; 01126 #endif 01127 /** 01128 * The POOL bucket type. This bucket represents a data that was allocated 01129 * from a pool. IF this bucket is still available when the pool is cleared, 01130 * the data is copied on to the heap. 01131 */ 01132 APU_DECLARE_DATA extern const apr_bucket_type_t apr_bucket_type_pool; 01133 /** 01134 * The PIPE bucket type. This bucket represents a pipe to another program. 01135 */ 01136 APU_DECLARE_DATA extern const apr_bucket_type_t apr_bucket_type_pipe; 01137 /** 01138 * The IMMORTAL bucket type. This bucket represents a segment of data that 01139 * the creator is willing to take responsibility for. The core will do 01140 * nothing with the data in an immortal bucket 01141 */ 01142 APU_DECLARE_DATA extern const apr_bucket_type_t apr_bucket_type_immortal; 01143 /** 01144 * The TRANSIENT bucket type. This bucket represents a data allocated off 01145 * the stack. When the setaside function is called, this data is copied on 01146 * to the heap 01147 */ 01148 APU_DECLARE_DATA extern const apr_bucket_type_t apr_bucket_type_transient; 01149 /** 01150 * The SOCKET bucket type. This bucket represents a socket to another machine 01151 */ 01152 APU_DECLARE_DATA extern const apr_bucket_type_t apr_bucket_type_socket; 01153 01154 01155 /* ***** Simple buckets ***** */ 01156 01157 /** 01158 * Split a simple bucket into two at the given point. Most non-reference 01159 * counting buckets that allow multiple references to the same block of 01160 * data (eg transient and immortal) will use this as their split function 01161 * without any additional type-specific handling. 01162 * @param b The bucket to be split 01163 * @param point The offset of the first byte in the new bucket 01164 * @return APR_EINVAL if the point is not within the bucket; 01165 * APR_ENOMEM if allocation failed; 01166 * or APR_SUCCESS 01167 */ 01168 APU_DECLARE_NONSTD(apr_status_t) apr_bucket_simple_split(apr_bucket *b, 01169 apr_size_t point); 01170 01171 /** 01172 * Copy a simple bucket. Most non-reference-counting buckets that allow 01173 * multiple references to the same block of data (eg transient and immortal) 01174 * will use this as their copy function without any additional type-specific 01175 * handling. 01176 * @param a The bucket to copy 01177 * @param b Returns a pointer to the new bucket 01178 * @return APR_ENOMEM if allocation failed; 01179 * or APR_SUCCESS 01180 */ 01181 APU_DECLARE_NONSTD(apr_status_t) apr_bucket_simple_copy(apr_bucket *a, 01182 apr_bucket **b); 01183 01184 01185 /* ***** Shared, reference-counted buckets ***** */ 01186 01187 /** 01188 * Initialize a bucket containing reference-counted data that may be 01189 * shared. The caller must allocate the bucket if necessary and 01190 * initialize its type-dependent fields, and allocate and initialize 01191 * its own private data structure. This function should only be called 01192 * by type-specific bucket creation functions. 01193 * @param b The bucket to initialize 01194 * @param data A pointer to the private data structure 01195 * with the reference count at the start 01196 * @param start The start of the data in the bucket 01197 * relative to the private base pointer 01198 * @param length The length of the data in the bucket 01199 * @return The new bucket, or NULL if allocation failed 01200 */ 01201 APU_DECLARE(apr_bucket *) apr_bucket_shared_make(apr_bucket *b, void *data, 01202 apr_off_t start, 01203 apr_size_t length); 01204 01205 /** 01206 * Decrement the refcount of the data in the bucket. This function 01207 * should only be called by type-specific bucket destruction functions. 01208 * @param data The private data pointer from the bucket to be destroyed 01209 * @return TRUE or FALSE; TRUE if the reference count is now 01210 * zero, indicating that the shared resource itself can 01211 * be destroyed by the caller. 01212 */ 01213 APU_DECLARE(int) apr_bucket_shared_destroy(void *data); 01214 01215 /** 01216 * Split a bucket into two at the given point, and adjust the refcount 01217 * to the underlying data. Most reference-counting bucket types will 01218 * be able to use this function as their split function without any 01219 * additional type-specific handling. 01220 * @param b The bucket to be split 01221 * @param point The offset of the first byte in the new bucket 01222 * @return APR_EINVAL if the point is not within the bucket; 01223 * APR_ENOMEM if allocation failed; 01224 * or APR_SUCCESS 01225 */ 01226 APU_DECLARE_NONSTD(apr_status_t) apr_bucket_shared_split(apr_bucket *b, 01227 apr_size_t point); 01228 01229 /** 01230 * Copy a refcounted bucket, incrementing the reference count. Most 01231 * reference-counting bucket types will be able to use this function 01232 * as their copy function without any additional type-specific handling. 01233 * @param a The bucket to copy 01234 * @param b Returns a pointer to the new bucket 01235 * @return APR_ENOMEM if allocation failed; 01236 or APR_SUCCESS 01237 */ 01238 APU_DECLARE_NONSTD(apr_status_t) apr_bucket_shared_copy(apr_bucket *a, 01239 apr_bucket **b); 01240 01241 01242 /* ***** Functions to Create Buckets of varying types ***** */ 01243 /* 01244 * Each bucket type foo has two initialization functions: 01245 * apr_bucket_foo_make which sets up some already-allocated memory as a 01246 * bucket of type foo; and apr_bucket_foo_create which allocates memory 01247 * for the bucket, calls apr_bucket_make_foo, and initializes the 01248 * bucket's list pointers. The apr_bucket_foo_make functions are used 01249 * inside the bucket code to change the type of buckets in place; 01250 * other code should call apr_bucket_foo_create. All the initialization 01251 * functions change nothing if they fail. 01252 */ 01253 01254 /** 01255 * Create an End of Stream bucket. This indicates that there is no more data 01256 * coming from down the filter stack. All filters should flush at this point. 01257 * @param list The freelist from which this bucket should be allocated 01258 * @return The new bucket, or NULL if allocation failed 01259 */ 01260 APU_DECLARE(apr_bucket *) apr_bucket_eos_create(apr_bucket_alloc_t *list); 01261 01262 /** 01263 * Make the bucket passed in an EOS bucket. This indicates that there is no 01264 * more data coming from down the filter stack. All filters should flush at 01265 * this point. 01266 * @param b The bucket to make into an EOS bucket 01267 * @return The new bucket, or NULL if allocation failed 01268 */ 01269 APU_DECLARE(apr_bucket *) apr_bucket_eos_make(apr_bucket *b); 01270 01271 /** 01272 * Create a flush bucket. This indicates that filters should flush their 01273 * data. There is no guarantee that they will flush it, but this is the 01274 * best we can do. 01275 * @param list The freelist from which this bucket should be allocated 01276 * @return The new bucket, or NULL if allocation failed 01277 */ 01278 APU_DECLARE(apr_bucket *) apr_bucket_flush_create(apr_bucket_alloc_t *list); 01279 01280 /** 01281 * Make the bucket passed in a FLUSH bucket. This indicates that filters 01282 * should flush their data. There is no guarantee that they will flush it, 01283 * but this is the best we can do. 01284 * @param b The bucket to make into a FLUSH bucket 01285 * @return The new bucket, or NULL if allocation failed 01286 */ 01287 APU_DECLARE(apr_bucket *) apr_bucket_flush_make(apr_bucket *b); 01288 01289 /** 01290 * Create a bucket referring to long-lived data. 01291 * @param buf The data to insert into the bucket 01292 * @param nbyte The size of the data to insert. 01293 * @param list The freelist from which this bucket should be allocated 01294 * @return The new bucket, or NULL if allocation failed 01295 */ 01296 APU_DECLARE(apr_bucket *) apr_bucket_immortal_create(const char *buf, 01297 apr_size_t nbyte, 01298 apr_bucket_alloc_t *list); 01299 01300 /** 01301 * Make the bucket passed in a bucket refer to long-lived data 01302 * @param b The bucket to make into a IMMORTAL bucket 01303 * @param buf The data to insert into the bucket 01304 * @param nbyte The size of the data to insert. 01305 * @return The new bucket, or NULL if allocation failed 01306 */ 01307 APU_DECLARE(apr_bucket *) apr_bucket_immortal_make(apr_bucket *b, 01308 const char *buf, 01309 apr_size_t nbyte); 01310 01311 /** 01312 * Create a bucket referring to data on the stack. 01313 * @param buf The data to insert into the bucket 01314 * @param nbyte The size of the data to insert. 01315 * @param list The freelist from which this bucket should be allocated 01316 * @return The new bucket, or NULL if allocation failed 01317 */ 01318 APU_DECLARE(apr_bucket *) apr_bucket_transient_create(const char *buf, 01319 apr_size_t nbyte, 01320 apr_bucket_alloc_t *list); 01321 01322 /** 01323 * Make the bucket passed in a bucket refer to stack data 01324 * @param b The bucket to make into a TRANSIENT bucket 01325 * @param buf The data to insert into the bucket 01326 * @param nbyte The size of the data to insert. 01327 * @return The new bucket, or NULL if allocation failed 01328 */ 01329 APU_DECLARE(apr_bucket *) apr_bucket_transient_make(apr_bucket *b, 01330 const char *buf, 01331 apr_size_t nbyte); 01332 01333 /** 01334 * Create a bucket referring to memory on the heap. If the caller asks 01335 * for the data to be copied, this function always allocates 4K of 01336 * memory so that more data can be added to the bucket without 01337 * requiring another allocation. Therefore not all the data may be put 01338 * into the bucket. If copying is not requested then the bucket takes 01339 * over responsibility for free()ing the memory. 01340 * @param buf The buffer to insert into the bucket 01341 * @param nbyte The size of the buffer to insert. 01342 * @param free_func Function to use to free the data; NULL indicates that the 01343 * bucket should make a copy of the data 01344 * @param list The freelist from which this bucket should be allocated 01345 * @return The new bucket, or NULL if allocation failed 01346 */ 01347 APU_DECLARE(apr_bucket *) apr_bucket_heap_create(const char *buf, 01348 apr_size_t nbyte, 01349 void (*free_func)(void *data), 01350 apr_bucket_alloc_t *list); 01351 /** 01352 * Make the bucket passed in a bucket refer to heap data 01353 * @param b The bucket to make into a HEAP bucket 01354 * @param buf The buffer to insert into the bucket 01355 * @param nbyte The size of the buffer to insert. 01356 * @param free_func Function to use to free the data; NULL indicates that the 01357 * bucket should make a copy of the data 01358 * @return The new bucket, or NULL if allocation failed 01359 */ 01360 APU_DECLARE(apr_bucket *) apr_bucket_heap_make(apr_bucket *b, const char *buf, 01361 apr_size_t nbyte, 01362 void (*free_func)(void *data)); 01363 01364 /** 01365 * Create a bucket referring to memory allocated from a pool. 01366 * 01367 * @param buf The buffer to insert into the bucket 01368 * @param length The number of bytes referred to by this bucket 01369 * @param pool The pool the memory was allocated from 01370 * @param list The freelist from which this bucket should be allocated 01371 * @return The new bucket, or NULL if allocation failed 01372 */ 01373 APU_DECLARE(apr_bucket *) apr_bucket_pool_create(const char *buf, 01374 apr_size_t length, 01375 apr_pool_t *pool, 01376 apr_bucket_alloc_t *list); 01377 01378 /** 01379 * Make the bucket passed in a bucket refer to pool data 01380 * @param b The bucket to make into a pool bucket 01381 * @param buf The buffer to insert into the bucket 01382 * @param length The number of bytes referred to by this bucket 01383 * @param pool The pool the memory was allocated from 01384 * @return The new bucket, or NULL if allocation failed 01385 */ 01386 APU_DECLARE(apr_bucket *) apr_bucket_pool_make(apr_bucket *b, const char *buf, 01387 apr_size_t length, 01388 apr_pool_t *pool); 01389 01390 #if APR_HAS_MMAP 01391 /** 01392 * Create a bucket referring to mmap()ed memory. 01393 * @param mm The mmap to insert into the bucket 01394 * @param start The offset of the first byte in the mmap 01395 * that this bucket refers to 01396 * @param length The number of bytes referred to by this bucket 01397 * @param list The freelist from which this bucket should be allocated 01398 * @return The new bucket, or NULL if allocation failed 01399 */ 01400 APU_DECLARE(apr_bucket *) apr_bucket_mmap_create(apr_mmap_t *mm, 01401 apr_off_t start, 01402 apr_size_t length, 01403 apr_bucket_alloc_t *list); 01404 01405 /** 01406 * Make the bucket passed in a bucket refer to an MMAP'ed file 01407 * @param b The bucket to make into a MMAP bucket 01408 * @param mm The mmap to insert into the bucket 01409 * @param start The offset of the first byte in the mmap 01410 * that this bucket refers to 01411 * @param length The number of bytes referred to by this bucket 01412 * @return The new bucket, or NULL if allocation failed 01413 */ 01414 APU_DECLARE(apr_bucket *) apr_bucket_mmap_make(apr_bucket *b, apr_mmap_t *mm, 01415 apr_off_t start, 01416 apr_size_t length); 01417 #endif 01418 01419 /** 01420 * Create a bucket referring to a socket. 01421 * @param thissock The socket to put in the bucket 01422 * @param list The freelist from which this bucket should be allocated 01423 * @return The new bucket, or NULL if allocation failed 01424 */ 01425 APU_DECLARE(apr_bucket *) apr_bucket_socket_create(apr_socket_t *thissock, 01426 apr_bucket_alloc_t *list); 01427 /** 01428 * Make the bucket passed in a bucket refer to a socket 01429 * @param b The bucket to make into a SOCKET bucket 01430 * @param thissock The socket to put in the bucket 01431 * @return The new bucket, or NULL if allocation failed 01432 */ 01433 APU_DECLARE(apr_bucket *) apr_bucket_socket_make(apr_bucket *b, 01434 apr_socket_t *thissock); 01435 01436 /** 01437 * Create a bucket referring to a pipe. 01438 * @param thispipe The pipe to put in the bucket 01439 * @param list The freelist from which this bucket should be allocated 01440 * @return The new bucket, or NULL if allocation failed 01441 */ 01442 APU_DECLARE(apr_bucket *) apr_bucket_pipe_create(apr_file_t *thispipe, 01443 apr_bucket_alloc_t *list); 01444 01445 /** 01446 * Make the bucket passed in a bucket refer to a pipe 01447 * @param b The bucket to make into a PIPE bucket 01448 * @param thispipe The pipe to put in the bucket 01449 * @return The new bucket, or NULL if allocation failed 01450 */ 01451 APU_DECLARE(apr_bucket *) apr_bucket_pipe_make(apr_bucket *b, 01452 apr_file_t *thispipe); 01453 01454 /** 01455 * Create a bucket referring to a file. 01456 * @param fd The file to put in the bucket 01457 * @param offset The offset where the data of interest begins in the file 01458 * @param len The amount of data in the file we are interested in 01459 * @param p The pool into which any needed structures should be created 01460 * while reading from this file bucket 01461 * @param list The freelist from which this bucket should be allocated 01462 * @return The new bucket, or NULL if allocation failed 01463 * @remark If the file is truncated such that the segment of the file 01464 * referenced by the bucket no longer exists, an attempt to read 01465 * from the bucket will fail with APR_EOF. 01466 * @remark apr_brigade_insert_file() should generally be used to 01467 * insert files into brigades, since that function can correctly 01468 * handle large file issues. 01469 */ 01470 APU_DECLARE(apr_bucket *) apr_bucket_file_create(apr_file_t *fd, 01471 apr_off_t offset, 01472 apr_size_t len, 01473 apr_pool_t *p, 01474 apr_bucket_alloc_t *list); 01475 01476 /** 01477 * Make the bucket passed in a bucket refer to a file 01478 * @param b The bucket to make into a FILE bucket 01479 * @param fd The file to put in the bucket 01480 * @param offset The offset where the data of interest begins in the file 01481 * @param len The amount of data in the file we are interested in 01482 * @param p The pool into which any needed structures should be created 01483 * while reading from this file bucket 01484 * @return The new bucket, or NULL if allocation failed 01485 */ 01486 APU_DECLARE(apr_bucket *) apr_bucket_file_make(apr_bucket *b, apr_file_t *fd, 01487 apr_off_t offset, 01488 apr_size_t len, apr_pool_t *p); 01489 01490 /** 01491 * Enable or disable memory-mapping for a FILE bucket (default is enabled) 01492 * @param b The bucket 01493 * @param enabled Whether memory-mapping should be enabled 01494 * @return APR_SUCCESS normally, or an error code if the operation fails 01495 */ 01496 APU_DECLARE(apr_status_t) apr_bucket_file_enable_mmap(apr_bucket *b, 01497 int enabled); 01498 01499 /** @} */ 01500 #ifdef __cplusplus 01501 } 01502 #endif 01503 01504 #endif /* !APR_BUCKETS_H */