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diff --git a/include/apr_buckets.h b/include/apr_buckets.h new file mode 100644 index 0000000..53633f5 --- /dev/null +++ b/include/apr_buckets.h @@ -0,0 +1,1600 @@ +/* Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed with + * this work for additional information regarding copyright ownership. + * The ASF licenses this file to You under the Apache License, Version 2.0 + * (the "License"); you may not use this file except in compliance with + * the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ +/** + * @file apr_buckets.h + * @brief APR-UTIL Buckets/Bucket Brigades + */ + +#ifndef APR_BUCKETS_H +#define APR_BUCKETS_H + +#if defined(APR_BUCKET_DEBUG) && !defined(APR_RING_DEBUG) +#define APR_RING_DEBUG +#endif + +#include "apu.h" +#include "apr_network_io.h" +#include "apr_file_io.h" +#include "apr_general.h" +#include "apr_mmap.h" +#include "apr_errno.h" +#include "apr_ring.h" +#include "apr.h" +#if APR_HAVE_SYS_UIO_H +#include <sys/uio.h> /* for struct iovec */ +#endif +#if APR_HAVE_STDARG_H +#include <stdarg.h> +#endif + +#ifdef __cplusplus +extern "C" { +#endif + +/** + * @defgroup APR_Util_Bucket_Brigades Bucket Brigades + * @ingroup APR_Util + * @{ + */ + +/** default bucket buffer size - 8KB minus room for memory allocator headers */ +#define APR_BUCKET_BUFF_SIZE 8000 + +/** Determines how a bucket or brigade should be read */ +typedef enum { + APR_BLOCK_READ, /**< block until data becomes available */ + APR_NONBLOCK_READ /**< return immediately if no data is available */ +} apr_read_type_e; + +/** + * The one-sentence buzzword-laden overview: Bucket brigades represent + * a complex data stream that can be passed through a layered IO + * system without unnecessary copying. A longer overview follows... + * + * A bucket brigade is a doubly linked list (ring) of buckets, so we + * aren't limited to inserting at the front and removing at the end. + * Buckets are only passed around as members of a brigade, although + * singleton buckets can occur for short periods of time. + * + * Buckets are data stores of various types. They can refer to data in + * memory, or part of a file or mmap area, or the output of a process, + * etc. Buckets also have some type-dependent accessor functions: + * read, split, copy, setaside, and destroy. + * + * read returns the address and size of the data in the bucket. If the + * data isn't in memory then it is read in and the bucket changes type + * so that it can refer to the new location of the data. If all the + * data doesn't fit in the bucket then a new bucket is inserted into + * the brigade to hold the rest of it. + * + * split divides the data in a bucket into two regions. After a split + * the original bucket refers to the first part of the data and a new + * bucket inserted into the brigade after the original bucket refers + * to the second part of the data. Reference counts are maintained as + * necessary. + * + * setaside ensures that the data in the bucket has a long enough + * lifetime. Sometimes it is convenient to create a bucket referring + * to data on the stack in the expectation that it will be consumed + * (output to the network) before the stack is unwound. If that + * expectation turns out not to be valid, the setaside function is + * called to move the data somewhere safer. + * + * copy makes a duplicate of the bucket structure as long as it's + * possible to have multiple references to a single copy of the + * data itself. Not all bucket types can be copied. + * + * destroy maintains the reference counts on the resources used by a + * bucket and frees them if necessary. + * + * Note: all of the above functions have wrapper macros (apr_bucket_read(), + * apr_bucket_destroy(), etc), and those macros should be used rather + * than using the function pointers directly. + * + * To write a bucket brigade, they are first made into an iovec, so that we + * don't write too little data at one time. Currently we ignore compacting the + * buckets into as few buckets as possible, but if we really want good + * performance, then we need to compact the buckets before we convert to an + * iovec, or possibly while we are converting to an iovec. + */ + +/* + * Forward declaration of the main types. + */ + +/** @see apr_bucket_brigade */ +typedef struct apr_bucket_brigade apr_bucket_brigade; +/** @see apr_bucket */ +typedef struct apr_bucket apr_bucket; +/** @see apr_bucket_alloc_t */ +typedef struct apr_bucket_alloc_t apr_bucket_alloc_t; + +/** @see apr_bucket_type_t */ +typedef struct apr_bucket_type_t apr_bucket_type_t; + +/** + * Basic bucket type + */ +struct apr_bucket_type_t { + /** + * The name of the bucket type + */ + const char *name; + /** + * The number of functions this bucket understands. Can not be less than + * five. + */ + int num_func; + /** + * Whether the bucket contains metadata (ie, information that + * describes the regular contents of the brigade). The metadata + * is not returned by apr_bucket_read() and is not indicated by + * the ->length of the apr_bucket itself. In other words, an + * empty bucket is safe to arbitrarily remove if and only if it + * contains no metadata. In this sense, "data" is just raw bytes + * that are the "content" of the brigade and "metadata" describes + * that data but is not a proper part of it. + */ + enum { + /** This bucket type represents actual data to send to the client. */ + APR_BUCKET_DATA = 0, + /** This bucket type represents metadata. */ + APR_BUCKET_METADATA = 1 + } is_metadata; + /** + * Free the private data and any resources used by the bucket (if they + * aren't shared with another bucket). This function is required to be + * implemented for all bucket types, though it might be a no-op on some + * of them (namely ones that never allocate any private data structures). + * @param data The private data pointer from the bucket to be destroyed + */ + void (*destroy)(void *data); + + /** + * Read the data from the bucket. This is required to be implemented + * for all bucket types. + * @param b The bucket to read from + * @param str A place to store the data read. Allocation should only be + * done if absolutely necessary. + * @param len The amount of data read. + * @param block Should this read function block if there is more data that + * cannot be read immediately. + */ + apr_status_t (*read)(apr_bucket *b, const char **str, apr_size_t *len, + apr_read_type_e block); + + /** + * Make it possible to set aside the data for at least as long as the + * given pool. Buckets containing data that could potentially die before + * this pool (e.g. the data resides on the stack, in a child pool of + * the given pool, or in a disjoint pool) must somehow copy, shift, or + * transform the data to have the proper lifetime. + * @param e The bucket to convert + * @remark Some bucket types contain data that will always outlive the + * bucket itself. For example no data (EOS and FLUSH), or the data + * resides in global, constant memory (IMMORTAL), or the data is on + * the heap (HEAP). For these buckets, apr_bucket_setaside_noop can + * be used. + */ + apr_status_t (*setaside)(apr_bucket *e, apr_pool_t *pool); + + /** + * Split one bucket in two at the specified position by duplicating + * the bucket structure (not the data) and modifying any necessary + * start/end/offset information. If it's not possible to do this + * for the bucket type (perhaps the length of the data is indeterminate, + * as with pipe and socket buckets), then APR_ENOTIMPL is returned. + * @param e The bucket to split + * @param point The offset of the first byte in the new bucket + */ + apr_status_t (*split)(apr_bucket *e, apr_size_t point); + + /** + * Copy the bucket structure (not the data), assuming that this is + * possible for the bucket type. If it's not, APR_ENOTIMPL is returned. + * @param e The bucket to copy + * @param c Returns a pointer to the new bucket + */ + apr_status_t (*copy)(apr_bucket *e, apr_bucket **c); + +}; + +/** + * apr_bucket structures are allocated on the malloc() heap and + * their lifetime is controlled by the parent apr_bucket_brigade + * structure. Buckets can move from one brigade to another e.g. by + * calling APR_BRIGADE_CONCAT(). In general the data in a bucket has + * the same lifetime as the bucket and is freed when the bucket is + * destroyed; if the data is shared by more than one bucket (e.g. + * after a split) the data is freed when the last bucket goes away. + */ +struct apr_bucket { + /** Links to the rest of the brigade */ + APR_RING_ENTRY(apr_bucket) link; + /** The type of bucket. */ + const apr_bucket_type_t *type; + /** The length of the data in the bucket. This could have been implemented + * with a function, but this is an optimization, because the most + * common thing to do will be to get the length. If the length is unknown, + * the value of this field will be (apr_size_t)(-1). + */ + apr_size_t length; + /** The start of the data in the bucket relative to the private base + * pointer. The vast majority of bucket types allow a fixed block of + * data to be referenced by multiple buckets, each bucket pointing to + * a different segment of the data. That segment starts at base+start + * and ends at base+start+length. + * If the length == (apr_size_t)(-1), then start == -1. + */ + apr_off_t start; + /** type-dependent data hangs off this pointer */ + void *data; + /** + * Pointer to function used to free the bucket. This function should + * always be defined and it should be consistent with the memory + * function used to allocate the bucket. For example, if malloc() is + * used to allocate the bucket, this pointer should point to free(). + * @param e Pointer to the bucket being freed + */ + void (*free)(void *e); + /** The freelist from which this bucket was allocated */ + apr_bucket_alloc_t *list; +}; + +/** A list of buckets */ +struct apr_bucket_brigade { + /** The pool to associate the brigade with. The data is not allocated out + * of the pool, but a cleanup is registered with this pool. If the + * brigade is destroyed by some mechanism other than pool destruction, + * the destroying function is responsible for killing the cleanup. + */ + apr_pool_t *p; + /** The buckets in the brigade are on this list. */ + /* + * The apr_bucket_list structure doesn't actually need a name tag + * because it has no existence independent of struct apr_bucket_brigade; + * the ring macros are designed so that you can leave the name tag + * argument empty in this situation but apparently the Windows compiler + * doesn't like that. + */ + APR_RING_HEAD(apr_bucket_list, apr_bucket) list; + /** The freelist from which this bucket was allocated */ + apr_bucket_alloc_t *bucket_alloc; +}; + + +/** + * Function called when a brigade should be flushed + */ +typedef apr_status_t (*apr_brigade_flush)(apr_bucket_brigade *bb, void *ctx); + +/* + * define APR_BUCKET_DEBUG if you want your brigades to be checked for + * validity at every possible instant. this will slow your code down + * substantially but is a very useful debugging tool. + */ +#ifdef APR_BUCKET_DEBUG + +#define APR_BRIGADE_CHECK_CONSISTENCY(b) \ + APR_RING_CHECK_CONSISTENCY(&(b)->list, apr_bucket, link) + +#define APR_BUCKET_CHECK_CONSISTENCY(e) \ + APR_RING_CHECK_ELEM_CONSISTENCY((e), apr_bucket, link) + +#else +/** + * checks the ring pointers in a bucket brigade for consistency. an + * abort() will be triggered if any inconsistencies are found. + * note: this is a no-op unless APR_BUCKET_DEBUG is defined. + * @param b The brigade + */ +#define APR_BRIGADE_CHECK_CONSISTENCY(b) +/** + * checks the brigade a bucket is in for ring consistency. an + * abort() will be triggered if any inconsistencies are found. + * note: this is a no-op unless APR_BUCKET_DEBUG is defined. + * @param e The bucket + */ +#define APR_BUCKET_CHECK_CONSISTENCY(e) +#endif + + +/** + * Wrappers around the RING macros to reduce the verbosity of the code + * that handles bucket brigades. + */ +/** + * The magic pointer value that indicates the head of the brigade + * @remark This is used to find the beginning and end of the brigade, eg: + * <pre> + * while (e != APR_BRIGADE_SENTINEL(b)) { + * ... + * e = APR_BUCKET_NEXT(e); + * } + * </pre> + * @param b The brigade + * @return The magic pointer value + */ +#define APR_BRIGADE_SENTINEL(b) APR_RING_SENTINEL(&(b)->list, apr_bucket, link) + +/** + * Determine if the bucket brigade is empty + * @param b The brigade to check + * @return true or false + */ +#define APR_BRIGADE_EMPTY(b) APR_RING_EMPTY(&(b)->list, apr_bucket, link) + +/** + * Return the first bucket in a brigade + * @param b The brigade to query + * @return The first bucket in the brigade + */ +#define APR_BRIGADE_FIRST(b) APR_RING_FIRST(&(b)->list) +/** + * Return the last bucket in a brigade + * @param b The brigade to query + * @return The last bucket in the brigade + */ +#define APR_BRIGADE_LAST(b) APR_RING_LAST(&(b)->list) + +/** + * Insert a single bucket at the front of a brigade + * @param b The brigade to add to + * @param e The bucket to insert + */ +#define APR_BRIGADE_INSERT_HEAD(b, e) do { \ + apr_bucket *ap__b = (e); \ + APR_RING_INSERT_HEAD(&(b)->list, ap__b, apr_bucket, link); \ + APR_BRIGADE_CHECK_CONSISTENCY((b)); \ + } while (0) + +/** + * Insert a single bucket at the end of a brigade + * @param b The brigade to add to + * @param e The bucket to insert + */ +#define APR_BRIGADE_INSERT_TAIL(b, e) do { \ + apr_bucket *ap__b = (e); \ + APR_RING_INSERT_TAIL(&(b)->list, ap__b, apr_bucket, link); \ + APR_BRIGADE_CHECK_CONSISTENCY((b)); \ + } while (0) + +/** + * Concatenate brigade b onto the end of brigade a, leaving brigade b empty + * @param a The first brigade + * @param b The second brigade + */ +#define APR_BRIGADE_CONCAT(a, b) do { \ + APR_RING_CONCAT(&(a)->list, &(b)->list, apr_bucket, link); \ + APR_BRIGADE_CHECK_CONSISTENCY((a)); \ + } while (0) + +/** + * Prepend brigade b onto the beginning of brigade a, leaving brigade b empty + * @param a The first brigade + * @param b The second brigade + */ +#define APR_BRIGADE_PREPEND(a, b) do { \ + APR_RING_PREPEND(&(a)->list, &(b)->list, apr_bucket, link); \ + APR_BRIGADE_CHECK_CONSISTENCY((a)); \ + } while (0) + +/** + * Insert a single bucket before a specified bucket + * @param a The bucket to insert before + * @param b The bucket to insert + */ +#define APR_BUCKET_INSERT_BEFORE(a, b) do { \ + apr_bucket *ap__a = (a), *ap__b = (b); \ + APR_RING_INSERT_BEFORE(ap__a, ap__b, link); \ + APR_BUCKET_CHECK_CONSISTENCY(ap__a); \ + } while (0) + +/** + * Insert a single bucket after a specified bucket + * @param a The bucket to insert after + * @param b The bucket to insert + */ +#define APR_BUCKET_INSERT_AFTER(a, b) do { \ + apr_bucket *ap__a = (a), *ap__b = (b); \ + APR_RING_INSERT_AFTER(ap__a, ap__b, link); \ + APR_BUCKET_CHECK_CONSISTENCY(ap__a); \ + } while (0) + +/** + * Get the next bucket in the list + * @param e The current bucket + * @return The next bucket + */ +#define APR_BUCKET_NEXT(e) APR_RING_NEXT((e), link) +/** + * Get the previous bucket in the list + * @param e The current bucket + * @return The previous bucket + */ +#define APR_BUCKET_PREV(e) APR_RING_PREV((e), link) + +/** + * Remove a bucket from its bucket brigade + * @param e The bucket to remove + */ +#define APR_BUCKET_REMOVE(e) APR_RING_REMOVE((e), link) + +/** + * Initialize a new bucket's prev/next pointers + * @param e The bucket to initialize + */ +#define APR_BUCKET_INIT(e) APR_RING_ELEM_INIT((e), link) + +/** + * Determine if a bucket contains metadata. An empty bucket is + * safe to arbitrarily remove if and only if this is false. + * @param e The bucket to inspect + * @return true or false + */ +#define APR_BUCKET_IS_METADATA(e) ((e)->type->is_metadata) + +/** + * Determine if a bucket is a FLUSH bucket + * @param e The bucket to inspect + * @return true or false + */ +#define APR_BUCKET_IS_FLUSH(e) ((e)->type == &apr_bucket_type_flush) +/** + * Determine if a bucket is an EOS bucket + * @param e The bucket to inspect + * @return true or false + */ +#define APR_BUCKET_IS_EOS(e) ((e)->type == &apr_bucket_type_eos) +/** + * Determine if a bucket is a FILE bucket + * @param e The bucket to inspect + * @return true or false + */ +#define APR_BUCKET_IS_FILE(e) ((e)->type == &apr_bucket_type_file) +/** + * Determine if a bucket is a PIPE bucket + * @param e The bucket to inspect + * @return true or false + */ +#define APR_BUCKET_IS_PIPE(e) ((e)->type == &apr_bucket_type_pipe) +/** + * Determine if a bucket is a SOCKET bucket + * @param e The bucket to inspect + * @return true or false + */ +#define APR_BUCKET_IS_SOCKET(e) ((e)->type == &apr_bucket_type_socket) +/** + * Determine if a bucket is a HEAP bucket + * @param e The bucket to inspect + * @return true or false + */ +#define APR_BUCKET_IS_HEAP(e) ((e)->type == &apr_bucket_type_heap) +/** + * Determine if a bucket is a TRANSIENT bucket + * @param e The bucket to inspect + * @return true or false + */ +#define APR_BUCKET_IS_TRANSIENT(e) ((e)->type == &apr_bucket_type_transient) +/** + * Determine if a bucket is a IMMORTAL bucket + * @param e The bucket to inspect + * @return true or false + */ +#define APR_BUCKET_IS_IMMORTAL(e) ((e)->type == &apr_bucket_type_immortal) +#if APR_HAS_MMAP +/** + * Determine if a bucket is a MMAP bucket + * @param e The bucket to inspect + * @return true or false + */ +#define APR_BUCKET_IS_MMAP(e) ((e)->type == &apr_bucket_type_mmap) +#endif +/** + * Determine if a bucket is a POOL bucket + * @param e The bucket to inspect + * @return true or false + */ +#define APR_BUCKET_IS_POOL(e) ((e)->type == &apr_bucket_type_pool) + +/* + * General-purpose reference counting for the various bucket types. + * + * Any bucket type that keeps track of the resources it uses (i.e. + * most of them except for IMMORTAL, TRANSIENT, and EOS) needs to + * attach a reference count to the resource so that it can be freed + * when the last bucket that uses it goes away. Resource-sharing may + * occur because of bucket splits or buckets that refer to globally + * cached data. */ + +/** @see apr_bucket_refcount */ +typedef struct apr_bucket_refcount apr_bucket_refcount; +/** + * The structure used to manage the shared resource must start with an + * apr_bucket_refcount which is updated by the general-purpose refcount + * code. A pointer to the bucket-type-dependent private data structure + * can be cast to a pointer to an apr_bucket_refcount and vice versa. + */ +struct apr_bucket_refcount { + /** The number of references to this bucket */ + int refcount; +}; + +/* ***** Reference-counted bucket types ***** */ + +/** @see apr_bucket_heap */ +typedef struct apr_bucket_heap apr_bucket_heap; +/** + * A bucket referring to data allocated off the heap. + */ +struct apr_bucket_heap { + /** Number of buckets using this memory */ + apr_bucket_refcount refcount; + /** The start of the data actually allocated. This should never be + * modified, it is only used to free the bucket. + */ + char *base; + /** how much memory was allocated */ + apr_size_t alloc_len; + /** function to use to delete the data */ + void (*free_func)(void *data); +}; + +/** @see apr_bucket_pool */ +typedef struct apr_bucket_pool apr_bucket_pool; +/** + * A bucket referring to data allocated from a pool + */ +struct apr_bucket_pool { + /** The pool bucket must be able to be easily morphed to a heap + * bucket if the pool gets cleaned up before all references are + * destroyed. This apr_bucket_heap structure is populated automatically + * when the pool gets cleaned up, and subsequent calls to pool_read() + * will result in the apr_bucket in question being morphed into a + * regular heap bucket. (To avoid having to do many extra refcount + * manipulations and b->data manipulations, the apr_bucket_pool + * struct actually *contains* the apr_bucket_heap struct that it + * will become as its first element; the two share their + * apr_bucket_refcount members.) + */ + apr_bucket_heap heap; + /** The block of data actually allocated from the pool. + * Segments of this block are referenced by adjusting + * the start and length of the apr_bucket accordingly. + * This will be NULL after the pool gets cleaned up. + */ + const char *base; + /** The pool the data was allocated from. When the pool + * is cleaned up, this gets set to NULL as an indicator + * to pool_read() that the data is now on the heap and + * so it should morph the bucket into a regular heap + * bucket before continuing. + */ + apr_pool_t *pool; + /** The freelist this structure was allocated from, which is + * needed in the cleanup phase in order to allocate space on the heap + */ + apr_bucket_alloc_t *list; +}; + +#if APR_HAS_MMAP +/** @see apr_bucket_mmap */ +typedef struct apr_bucket_mmap apr_bucket_mmap; +/** + * A bucket referring to an mmap()ed file + */ +struct apr_bucket_mmap { + /** Number of buckets using this memory */ + apr_bucket_refcount refcount; + /** The mmap this sub_bucket refers to */ + apr_mmap_t *mmap; +}; +#endif + +/** @see apr_bucket_file */ +typedef struct apr_bucket_file apr_bucket_file; +/** + * A bucket referring to an file + */ +struct apr_bucket_file { + /** Number of buckets using this memory */ + apr_bucket_refcount refcount; + /** The file this bucket refers to */ + apr_file_t *fd; + /** The pool into which any needed structures should + * be created while reading from this file bucket */ + apr_pool_t *readpool; +#if APR_HAS_MMAP + /** Whether this bucket should be memory-mapped if + * a caller tries to read from it */ + int can_mmap; +#endif /* APR_HAS_MMAP */ + /** File read block size */ + apr_size_t read_size; +}; + +/** @see apr_bucket_structs */ +typedef union apr_bucket_structs apr_bucket_structs; +/** + * A union of all bucket structures so we know what + * the max size is. + */ +union apr_bucket_structs { + apr_bucket b; /**< Bucket */ + apr_bucket_heap heap; /**< Heap */ + apr_bucket_pool pool; /**< Pool */ +#if APR_HAS_MMAP + apr_bucket_mmap mmap; /**< MMap */ +#endif + apr_bucket_file file; /**< File */ +}; + +/** + * The amount that apr_bucket_alloc() should allocate in the common case. + * Note: this is twice as big as apr_bucket_structs to allow breathing + * room for third-party bucket types. + */ +#define APR_BUCKET_ALLOC_SIZE APR_ALIGN_DEFAULT(2*sizeof(apr_bucket_structs)) + +/* ***** Bucket Brigade Functions ***** */ +/** + * Create a new bucket brigade. The bucket brigade is originally empty. + * @param p The pool to associate with the brigade. Data is not allocated out + * of the pool, but a cleanup is registered. + * @param list The bucket allocator to use + * @return The empty bucket brigade + */ +APU_DECLARE(apr_bucket_brigade *) apr_brigade_create(apr_pool_t *p, + apr_bucket_alloc_t *list); + +/** + * destroy an entire bucket brigade. This includes destroying all of the + * buckets within the bucket brigade's bucket list. + * @param b The bucket brigade to destroy + */ +APU_DECLARE(apr_status_t) apr_brigade_destroy(apr_bucket_brigade *b); + +/** + * empty out an entire bucket brigade. This includes destroying all of the + * buckets within the bucket brigade's bucket list. This is similar to + * apr_brigade_destroy(), except that it does not deregister the brigade's + * pool cleanup function. + * @param data The bucket brigade to clean up + * @remark Generally, you should use apr_brigade_destroy(). This function + * can be useful in situations where you have a single brigade that + * you wish to reuse many times by destroying all of the buckets in + * the brigade and putting new buckets into it later. + */ +APU_DECLARE(apr_status_t) apr_brigade_cleanup(void *data); + +/** + * Move the buckets from the tail end of the existing brigade @a b into + * the brigade @a a. If @a a is NULL a new brigade is created. Buckets + * from @a e to the last bucket (inclusively) of brigade @a b are moved + * from @a b to the returned brigade @a a. + * + * @param b The brigade to split + * @param e The first bucket to move + * @param a The brigade which should be used for the result or NULL if + * a new brigade should be created. The brigade @a a will be + * cleared if it is not empty. + * @return The brigade supplied in @a a or a new one if @a a was NULL. + * @warning Note that this function allocates a new brigade if @a a is + * NULL so memory consumption should be carefully considered. + */ +APU_DECLARE(apr_bucket_brigade *) apr_brigade_split_ex(apr_bucket_brigade *b, + apr_bucket *e, + apr_bucket_brigade *a); + +/** + * Create a new bucket brigade and move the buckets from the tail end + * of an existing brigade into the new brigade. Buckets from + * @a e to the last bucket (inclusively) of brigade @a b + * are moved from @a b to the returned brigade. + * @param b The brigade to split + * @param e The first bucket to move + * @return The new brigade + * @warning Note that this function always allocates a new brigade + * so memory consumption should be carefully considered. + */ +APU_DECLARE(apr_bucket_brigade *) apr_brigade_split(apr_bucket_brigade *b, + apr_bucket *e); + +/** + * Partition a bucket brigade at a given offset (in bytes from the start of + * the brigade). This is useful whenever a filter wants to use known ranges + * of bytes from the brigade; the ranges can even overlap. + * @param b The brigade to partition + * @param point The offset at which to partition the brigade + * @param after_point Returns a pointer to the first bucket after the partition + * @return APR_SUCCESS on success, APR_INCOMPLETE if the contents of the + * brigade were shorter than @a point, or an error code. + * @remark if APR_INCOMPLETE is returned, @a after_point will be set to + * the brigade sentinel. + */ +APU_DECLARE(apr_status_t) apr_brigade_partition(apr_bucket_brigade *b, + apr_off_t point, + apr_bucket **after_point); + +/** + * Return the total length of the brigade. + * @param bb The brigade to compute the length of + * @param read_all Read unknown-length buckets to force a size + * @param length Returns the length of the brigade (up to the end, or up + * to a bucket read error), or -1 if the brigade has buckets + * of indeterminate length and read_all is 0. + */ +APU_DECLARE(apr_status_t) apr_brigade_length(apr_bucket_brigade *bb, + int read_all, + apr_off_t *length); + +/** + * Take a bucket brigade and store the data in a flat char* + * @param bb The bucket brigade to create the char* from + * @param c The char* to write into + * @param len The maximum length of the char array. On return, it is the + * actual length of the char array. + */ +APU_DECLARE(apr_status_t) apr_brigade_flatten(apr_bucket_brigade *bb, + char *c, + apr_size_t *len); + +/** + * Creates a pool-allocated string representing a flat bucket brigade + * @param bb The bucket brigade to create the char array from + * @param c On return, the allocated char array + * @param len On return, the length of the char array. + * @param pool The pool to allocate the string from. + */ +APU_DECLARE(apr_status_t) apr_brigade_pflatten(apr_bucket_brigade *bb, + char **c, + apr_size_t *len, + apr_pool_t *pool); + +/** + * Split a brigade to represent one LF line. + * @param bbOut The bucket brigade that will have the LF line appended to. + * @param bbIn The input bucket brigade to search for a LF-line. + * @param block The blocking mode to be used to split the line. + * @param maxbytes The maximum bytes to read. If this many bytes are seen + * without a LF, the brigade will contain a partial line. + */ +APU_DECLARE(apr_status_t) apr_brigade_split_line(apr_bucket_brigade *bbOut, + apr_bucket_brigade *bbIn, + apr_read_type_e block, + apr_off_t maxbytes); + +/** + * Create an iovec of the elements in a bucket_brigade... return number + * of elements used. This is useful for writing to a file or to the + * network efficiently. + * @param b The bucket brigade to create the iovec from + * @param vec The iovec to create + * @param nvec The number of elements in the iovec. On return, it is the + * number of iovec elements actually filled out. + */ +APU_DECLARE(apr_status_t) apr_brigade_to_iovec(apr_bucket_brigade *b, + struct iovec *vec, int *nvec); + +/** + * This function writes a list of strings into a bucket brigade. + * @param b The bucket brigade to add to + * @param flush The flush function to use if the brigade is full + * @param ctx The structure to pass to the flush function + * @param va A list of strings to add + * @return APR_SUCCESS or error code. + */ +APU_DECLARE(apr_status_t) apr_brigade_vputstrs(apr_bucket_brigade *b, + apr_brigade_flush flush, + void *ctx, + va_list va); + +/** + * This function writes a string into a bucket brigade. + * + * The apr_brigade_write function attempts to be efficient with the + * handling of heap buckets. Regardless of the amount of data stored + * inside a heap bucket, heap buckets are a fixed size to promote their + * reuse. + * + * If an attempt is made to write a string to a brigade that already + * ends with a heap bucket, this function will attempt to pack the + * string into the remaining space in the previous heap bucket, before + * allocating a new heap bucket. + * + * This function always returns APR_SUCCESS, unless a flush function is + * passed, in which case the return value of the flush function will be + * returned if used. + * @param b The bucket brigade to add to + * @param flush The flush function to use if the brigade is full + * @param ctx The structure to pass to the flush function + * @param str The string to add + * @param nbyte The number of bytes to write + * @return APR_SUCCESS or error code + */ +APU_DECLARE(apr_status_t) apr_brigade_write(apr_bucket_brigade *b, + apr_brigade_flush flush, void *ctx, + const char *str, apr_size_t nbyte); + +/** + * This function writes multiple strings into a bucket brigade. + * @param b The bucket brigade to add to + * @param flush The flush function to use if the brigade is full + * @param ctx The structure to pass to the flush function + * @param vec The strings to add (address plus length for each) + * @param nvec The number of entries in iovec + * @return APR_SUCCESS or error code + */ +APU_DECLARE(apr_status_t) apr_brigade_writev(apr_bucket_brigade *b, + apr_brigade_flush flush, + void *ctx, + const struct iovec *vec, + apr_size_t nvec); + +/** + * This function writes a string into a bucket brigade. + * @param bb The bucket brigade to add to + * @param flush The flush function to use if the brigade is full + * @param ctx The structure to pass to the flush function + * @param str The string to add + * @return APR_SUCCESS or error code + */ +APU_DECLARE(apr_status_t) apr_brigade_puts(apr_bucket_brigade *bb, + apr_brigade_flush flush, void *ctx, + const char *str); + +/** + * This function writes a character into a bucket brigade. + * @param b The bucket brigade to add to + * @param flush The flush function to use if the brigade is full + * @param ctx The structure to pass to the flush function + * @param c The character to add + * @return APR_SUCCESS or error code + */ +APU_DECLARE(apr_status_t) apr_brigade_putc(apr_bucket_brigade *b, + apr_brigade_flush flush, void *ctx, + const char c); + +/** + * This function writes an unspecified number of strings into a bucket brigade. + * @param b The bucket brigade to add to + * @param flush The flush function to use if the brigade is full + * @param ctx The structure to pass to the flush function + * @param ... The strings to add + * @return APR_SUCCESS or error code + */ +APU_DECLARE_NONSTD(apr_status_t) apr_brigade_putstrs(apr_bucket_brigade *b, + apr_brigade_flush flush, + void *ctx, ...); + +/** + * Evaluate a printf and put the resulting string at the end + * of the bucket brigade. + * @param b The brigade to write to + * @param flush The flush function to use if the brigade is full + * @param ctx The structure to pass to the flush function + * @param fmt The format of the string to write + * @param ... The arguments to fill out the format + * @return APR_SUCCESS or error code + */ +APU_DECLARE_NONSTD(apr_status_t) apr_brigade_printf(apr_bucket_brigade *b, + apr_brigade_flush flush, + void *ctx, + const char *fmt, ...) + __attribute__((format(printf,4,5))); + +/** + * Evaluate a printf and put the resulting string at the end + * of the bucket brigade. + * @param b The brigade to write to + * @param flush The flush function to use if the brigade is full + * @param ctx The structure to pass to the flush function + * @param fmt The format of the string to write + * @param va The arguments to fill out the format + * @return APR_SUCCESS or error code + */ +APU_DECLARE(apr_status_t) apr_brigade_vprintf(apr_bucket_brigade *b, + apr_brigade_flush flush, + void *ctx, + const char *fmt, va_list va); + +/** + * Utility function to insert a file (or a segment of a file) onto the + * end of the brigade. The file is split into multiple buckets if it + * is larger than the maximum size which can be represented by a + * single bucket. + * @param bb the brigade to insert into + * @param f the file to insert + * @param start the offset of the start of the segment + * @param len the length of the segment of the file to insert + * @param p pool from which file buckets are allocated + * @return the last bucket inserted + */ +APU_DECLARE(apr_bucket *) apr_brigade_insert_file(apr_bucket_brigade *bb, + apr_file_t *f, + apr_off_t start, + apr_off_t len, + apr_pool_t *p); + + + +/* ***** Bucket freelist functions ***** */ +/** + * Create a bucket allocator. + * @param p This pool's underlying apr_allocator_t is used to allocate memory + * for the bucket allocator. When the pool is destroyed, the bucket + * allocator's cleanup routine will free all memory that has been + * allocated from it. + * @remark The reason the allocator gets its memory from the pool's + * apr_allocator_t rather than from the pool itself is because + * the bucket allocator will free large memory blocks back to the + * allocator when it's done with them, thereby preventing memory + * footprint growth that would occur if we allocated from the pool. + * @warning The allocator must never be used by more than one thread at a time. + */ +APU_DECLARE_NONSTD(apr_bucket_alloc_t *) apr_bucket_alloc_create(apr_pool_t *p); + +/** + * Create a bucket allocator. + * @param allocator This apr_allocator_t is used to allocate both the bucket + * allocator and all memory handed out by the bucket allocator. The + * caller is responsible for destroying the bucket allocator and the + * apr_allocator_t -- no automatic cleanups will happen. + * @warning The allocator must never be used by more than one thread at a time. + */ +APU_DECLARE_NONSTD(apr_bucket_alloc_t *) apr_bucket_alloc_create_ex(apr_allocator_t *allocator); + +/** + * Destroy a bucket allocator. + * @param list The allocator to be destroyed + */ +APU_DECLARE_NONSTD(void) apr_bucket_alloc_destroy(apr_bucket_alloc_t *list); + +/** + * Get the aligned size corresponding to the requested size, but minus the + * allocator(s) overhead such that the allocation would remain in the + * same boundary. + * @param list The allocator from which to the memory would be allocated. + * @param size The requested size. + * @return The corresponding aligned/floored size. + */ +APU_DECLARE_NONSTD(apr_size_t) apr_bucket_alloc_aligned_floor(apr_bucket_alloc_t *list, + apr_size_t size) + __attribute__((nonnull(1))); + +/** + * Allocate memory for use by the buckets. + * @param size The amount to allocate. + * @param list The allocator from which to allocate the memory. + */ +APU_DECLARE_NONSTD(void *) apr_bucket_alloc(apr_size_t size, apr_bucket_alloc_t *list); + +/** + * Free memory previously allocated with apr_bucket_alloc(). + * @param block The block of memory to be freed. + */ +APU_DECLARE_NONSTD(void) apr_bucket_free(void *block); + + +/* ***** Bucket Functions ***** */ +/** + * Free the resources used by a bucket. If multiple buckets refer to + * the same resource it is freed when the last one goes away. + * @see apr_bucket_delete() + * @param e The bucket to destroy + */ +#define apr_bucket_destroy(e) do { \ + apr_bucket *apr__d = (e); \ + apr__d->type->destroy(apr__d->data); \ + apr__d->free(apr__d); \ + } while (0) + +/** + * Delete a bucket by removing it from its brigade (if any) and then + * destroying it. + * @remark This mainly acts as an aid in avoiding code verbosity. It is + * the preferred exact equivalent to: + * <pre> + * APR_BUCKET_REMOVE(e); + * apr_bucket_destroy(e); + * </pre> + * @param e The bucket to delete + */ +#define apr_bucket_delete(e) do { \ + apr_bucket *apr__b = (e); \ + APR_BUCKET_REMOVE(apr__b); \ + apr_bucket_destroy(apr__b); \ + } while (0) + +/** + * Read some data from the bucket. + * + * The apr_bucket_read function returns a convenient amount of data + * from the bucket provided, writing the address and length of the + * data to the pointers provided by the caller. The function tries + * as hard as possible to avoid a memory copy. + * + * Buckets are expected to be a member of a brigade at the time they + * are read. + * + * In typical application code, buckets are read in a loop, and after + * each bucket is read and processed, it is moved or deleted from the + * brigade and the next bucket read. + * + * The definition of "convenient" depends on the type of bucket that + * is being read, and is decided by APR. In the case of memory based + * buckets such as heap and immortal buckets, a pointer will be + * returned to the location of the buffer containing the complete + * contents of the bucket. + * + * Some buckets, such as the socket bucket, might have no concept + * of length. If an attempt is made to read such a bucket, the + * apr_bucket_read function will read a convenient amount of data + * from the socket. The socket bucket is magically morphed into a + * heap bucket containing the just-read data, and a new socket bucket + * is inserted just after this heap bucket. + * + * To understand why apr_bucket_read might do this, consider the loop + * described above to read and process buckets. The current bucket + * is magically morphed into a heap bucket and returned to the caller. + * The caller processes the data, and deletes the heap bucket, moving + * onto the next bucket, the new socket bucket. This process repeats, + * giving the illusion of a bucket brigade that contains potentially + * infinite amounts of data. It is up to the caller to decide at what + * point to stop reading buckets. + * + * Some buckets, such as the file bucket, might have a fixed size, + * but be significantly larger than is practical to store in RAM in + * one go. As with the socket bucket, if an attempt is made to read + * from a file bucket, the file bucket is magically morphed into a + * heap bucket containing a convenient amount of data read from the + * current offset in the file. During the read, the offset will be + * moved forward on the file, and a new file bucket will be inserted + * directly after the current bucket representing the remainder of the + * file. If the heap bucket was large enough to store the whole + * remainder of the file, no more file buckets are inserted, and the + * file bucket will disappear completely. + * + * The pattern for reading buckets described above does create the + * illusion that the code is willing to swallow buckets that might be + * too large for the system to handle in one go. This however is just + * an illusion: APR will always ensure that large (file) or infinite + * (socket) buckets are broken into convenient bite sized heap buckets + * before data is returned to the caller. + * + * There is a potential gotcha to watch for: if buckets are read in a + * loop, and aren't deleted after being processed, the potentially large + * bucket will slowly be converted into RAM resident heap buckets. If + * the file is larger than available RAM, an out of memory condition + * could be caused if the application is not careful to manage this. + * + * @param e The bucket to read from + * @param str The location to store a pointer to the data in + * @param len The location to store the amount of data read + * @param block Whether the read function blocks + */ +#define apr_bucket_read(e,str,len,block) (e)->type->read(e, str, len, block) + +/** + * Setaside data so that stack data is not destroyed on returning from + * the function + * @param e The bucket to setaside + * @param p The pool to setaside into + */ +#define apr_bucket_setaside(e,p) (e)->type->setaside(e,p) + +/** + * Split one bucket in two at the point provided. + * + * Once split, the original bucket becomes the first of the two new buckets. + * + * (It is assumed that the bucket is a member of a brigade when this + * function is called). + * @param e The bucket to split + * @param point The offset to split the bucket at + */ +#define apr_bucket_split(e,point) (e)->type->split(e, point) + +/** + * Copy a bucket. + * @param e The bucket to copy + * @param c Returns a pointer to the new bucket + */ +#define apr_bucket_copy(e,c) (e)->type->copy(e, c) + +/* Bucket type handling */ + +/** + * This function simply returns APR_SUCCESS to denote that the bucket does + * not require anything to happen for its setaside() function. This is + * appropriate for buckets that have "immortal" data -- the data will live + * at least as long as the bucket. + * @param data The bucket to setaside + * @param pool The pool defining the desired lifetime of the bucket data + * @return APR_SUCCESS + */ +APU_DECLARE_NONSTD(apr_status_t) apr_bucket_setaside_noop(apr_bucket *data, + apr_pool_t *pool); + +/** + * A place holder function that signifies that the setaside function was not + * implemented for this bucket + * @param data The bucket to setaside + * @param pool The pool defining the desired lifetime of the bucket data + * @return APR_ENOTIMPL + */ +APU_DECLARE_NONSTD(apr_status_t) apr_bucket_setaside_notimpl(apr_bucket *data, + apr_pool_t *pool); + +/** + * A place holder function that signifies that the split function was not + * implemented for this bucket + * @param data The bucket to split + * @param point The location to split the bucket + * @return APR_ENOTIMPL + */ +APU_DECLARE_NONSTD(apr_status_t) apr_bucket_split_notimpl(apr_bucket *data, + apr_size_t point); + +/** + * A place holder function that signifies that the copy function was not + * implemented for this bucket + * @param e The bucket to copy + * @param c Returns a pointer to the new bucket + * @return APR_ENOTIMPL + */ +APU_DECLARE_NONSTD(apr_status_t) apr_bucket_copy_notimpl(apr_bucket *e, + apr_bucket **c); + +/** + * A place holder function that signifies that this bucket does not need + * to do anything special to be destroyed. That's only the case for buckets + * that either have no data (metadata buckets) or buckets whose data pointer + * points to something that's not a bucket-type-specific structure, as with + * simple buckets where data points to a string and pipe buckets where data + * points directly to the apr_file_t. + * @param data The bucket data to destroy + */ +APU_DECLARE_NONSTD(void) apr_bucket_destroy_noop(void *data); + +/** + * There is no apr_bucket_destroy_notimpl, because destruction is required + * to be implemented (it could be a noop, but only if that makes sense for + * the bucket type) + */ + +/* There is no apr_bucket_read_notimpl, because it is a required function + */ + + +/* All of the bucket types implemented by the core */ +/** + * The flush bucket type. This signifies that all data should be flushed to + * the next filter. The flush bucket should be sent with the other buckets. + */ +APU_DECLARE_DATA extern const apr_bucket_type_t apr_bucket_type_flush; +/** + * The EOS bucket type. This signifies that there will be no more data, ever. + * All filters MUST send all data to the next filter when they receive a + * bucket of this type + */ +APU_DECLARE_DATA extern const apr_bucket_type_t apr_bucket_type_eos; +/** + * The FILE bucket type. This bucket represents a file on disk + */ +APU_DECLARE_DATA extern const apr_bucket_type_t apr_bucket_type_file; +/** + * The HEAP bucket type. This bucket represents a data allocated from the + * heap. + */ +APU_DECLARE_DATA extern const apr_bucket_type_t apr_bucket_type_heap; +#if APR_HAS_MMAP +/** + * The MMAP bucket type. This bucket represents an MMAP'ed file + */ +APU_DECLARE_DATA extern const apr_bucket_type_t apr_bucket_type_mmap; +#endif +/** + * The POOL bucket type. This bucket represents a data that was allocated + * from a pool. IF this bucket is still available when the pool is cleared, + * the data is copied on to the heap. + */ +APU_DECLARE_DATA extern const apr_bucket_type_t apr_bucket_type_pool; +/** + * The PIPE bucket type. This bucket represents a pipe to another program. + */ +APU_DECLARE_DATA extern const apr_bucket_type_t apr_bucket_type_pipe; +/** + * The IMMORTAL bucket type. This bucket represents a segment of data that + * the creator is willing to take responsibility for. The core will do + * nothing with the data in an immortal bucket + */ +APU_DECLARE_DATA extern const apr_bucket_type_t apr_bucket_type_immortal; +/** + * The TRANSIENT bucket type. This bucket represents a data allocated off + * the stack. When the setaside function is called, this data is copied on + * to the heap + */ +APU_DECLARE_DATA extern const apr_bucket_type_t apr_bucket_type_transient; +/** + * The SOCKET bucket type. This bucket represents a socket to another machine + */ +APU_DECLARE_DATA extern const apr_bucket_type_t apr_bucket_type_socket; + + +/* ***** Simple buckets ***** */ + +/** + * Split a simple bucket into two at the given point. Most non-reference + * counting buckets that allow multiple references to the same block of + * data (eg transient and immortal) will use this as their split function + * without any additional type-specific handling. + * @param b The bucket to be split + * @param point The offset of the first byte in the new bucket + * @return APR_EINVAL if the point is not within the bucket; + * APR_ENOMEM if allocation failed; + * or APR_SUCCESS + */ +APU_DECLARE_NONSTD(apr_status_t) apr_bucket_simple_split(apr_bucket *b, + apr_size_t point); + +/** + * Copy a simple bucket. Most non-reference-counting buckets that allow + * multiple references to the same block of data (eg transient and immortal) + * will use this as their copy function without any additional type-specific + * handling. + * @param a The bucket to copy + * @param b Returns a pointer to the new bucket + * @return APR_ENOMEM if allocation failed; + * or APR_SUCCESS + */ +APU_DECLARE_NONSTD(apr_status_t) apr_bucket_simple_copy(apr_bucket *a, + apr_bucket **b); + + +/* ***** Shared, reference-counted buckets ***** */ + +/** + * Initialize a bucket containing reference-counted data that may be + * shared. The caller must allocate the bucket if necessary and + * initialize its type-dependent fields, and allocate and initialize + * its own private data structure. This function should only be called + * by type-specific bucket creation functions. + * @param b The bucket to initialize + * @param data A pointer to the private data structure + * with the reference count at the start + * @param start The start of the data in the bucket + * relative to the private base pointer + * @param length The length of the data in the bucket + * @return The new bucket, or NULL if allocation failed + */ +APU_DECLARE(apr_bucket *) apr_bucket_shared_make(apr_bucket *b, void *data, + apr_off_t start, + apr_size_t length); + +/** + * Decrement the refcount of the data in the bucket. This function + * should only be called by type-specific bucket destruction functions. + * @param data The private data pointer from the bucket to be destroyed + * @return TRUE or FALSE; TRUE if the reference count is now + * zero, indicating that the shared resource itself can + * be destroyed by the caller. + */ +APU_DECLARE(int) apr_bucket_shared_destroy(void *data); + +/** + * Split a bucket into two at the given point, and adjust the refcount + * to the underlying data. Most reference-counting bucket types will + * be able to use this function as their split function without any + * additional type-specific handling. + * @param b The bucket to be split + * @param point The offset of the first byte in the new bucket + * @return APR_EINVAL if the point is not within the bucket; + * APR_ENOMEM if allocation failed; + * or APR_SUCCESS + */ +APU_DECLARE_NONSTD(apr_status_t) apr_bucket_shared_split(apr_bucket *b, + apr_size_t point); + +/** + * Copy a refcounted bucket, incrementing the reference count. Most + * reference-counting bucket types will be able to use this function + * as their copy function without any additional type-specific handling. + * @param a The bucket to copy + * @param b Returns a pointer to the new bucket + * @return APR_ENOMEM if allocation failed; + or APR_SUCCESS + */ +APU_DECLARE_NONSTD(apr_status_t) apr_bucket_shared_copy(apr_bucket *a, + apr_bucket **b); + + +/* ***** Functions to Create Buckets of varying types ***** */ +/* + * Each bucket type foo has two initialization functions: + * apr_bucket_foo_make which sets up some already-allocated memory as a + * bucket of type foo; and apr_bucket_foo_create which allocates memory + * for the bucket, calls apr_bucket_make_foo, and initializes the + * bucket's list pointers. The apr_bucket_foo_make functions are used + * inside the bucket code to change the type of buckets in place; + * other code should call apr_bucket_foo_create. All the initialization + * functions change nothing if they fail. + */ + +/** + * Create an End of Stream bucket. This indicates that there is no more data + * coming from down the filter stack. All filters should flush at this point. + * @param list The freelist from which this bucket should be allocated + * @return The new bucket, or NULL if allocation failed + */ +APU_DECLARE(apr_bucket *) apr_bucket_eos_create(apr_bucket_alloc_t *list); + +/** + * Make the bucket passed in an EOS bucket. This indicates that there is no + * more data coming from down the filter stack. All filters should flush at + * this point. + * @param b The bucket to make into an EOS bucket + * @return The new bucket, or NULL if allocation failed + */ +APU_DECLARE(apr_bucket *) apr_bucket_eos_make(apr_bucket *b); + +/** + * Create a flush bucket. This indicates that filters should flush their + * data. There is no guarantee that they will flush it, but this is the + * best we can do. + * @param list The freelist from which this bucket should be allocated + * @return The new bucket, or NULL if allocation failed + */ +APU_DECLARE(apr_bucket *) apr_bucket_flush_create(apr_bucket_alloc_t *list); + +/** + * Make the bucket passed in a FLUSH bucket. This indicates that filters + * should flush their data. There is no guarantee that they will flush it, + * but this is the best we can do. + * @param b The bucket to make into a FLUSH bucket + * @return The new bucket, or NULL if allocation failed + */ +APU_DECLARE(apr_bucket *) apr_bucket_flush_make(apr_bucket *b); + +/** + * Create a bucket referring to long-lived data. + * @param buf The data to insert into the bucket + * @param nbyte The size of the data to insert. + * @param list The freelist from which this bucket should be allocated + * @return The new bucket, or NULL if allocation failed + */ +APU_DECLARE(apr_bucket *) apr_bucket_immortal_create(const char *buf, + apr_size_t nbyte, + apr_bucket_alloc_t *list); + +/** + * Make the bucket passed in a bucket refer to long-lived data + * @param b The bucket to make into a IMMORTAL bucket + * @param buf The data to insert into the bucket + * @param nbyte The size of the data to insert. + * @return The new bucket, or NULL if allocation failed + */ +APU_DECLARE(apr_bucket *) apr_bucket_immortal_make(apr_bucket *b, + const char *buf, + apr_size_t nbyte); + +/** + * Create a bucket referring to data on the stack. + * @param buf The data to insert into the bucket + * @param nbyte The size of the data to insert. + * @param list The freelist from which this bucket should be allocated + * @return The new bucket, or NULL if allocation failed + */ +APU_DECLARE(apr_bucket *) apr_bucket_transient_create(const char *buf, + apr_size_t nbyte, + apr_bucket_alloc_t *list); + +/** + * Make the bucket passed in a bucket refer to stack data + * @param b The bucket to make into a TRANSIENT bucket + * @param buf The data to insert into the bucket + * @param nbyte The size of the data to insert. + * @return The new bucket, or NULL if allocation failed + */ +APU_DECLARE(apr_bucket *) apr_bucket_transient_make(apr_bucket *b, + const char *buf, + apr_size_t nbyte); + +/** + * Create a bucket referring to memory on the heap. If the caller asks + * for the data to be copied, this function always allocates 4K of + * memory so that more data can be added to the bucket without + * requiring another allocation. Therefore not all the data may be put + * into the bucket. If copying is not requested then the bucket takes + * over responsibility for free()ing the memory. + * @param buf The buffer to insert into the bucket + * @param nbyte The size of the buffer to insert. + * @param free_func Function to use to free the data; NULL indicates that the + * bucket should make a copy of the data + * @param list The freelist from which this bucket should be allocated + * @return The new bucket, or NULL if allocation failed + */ +APU_DECLARE(apr_bucket *) apr_bucket_heap_create(const char *buf, + apr_size_t nbyte, + void (*free_func)(void *data), + apr_bucket_alloc_t *list); +/** + * Make the bucket passed in a bucket refer to heap data + * @param b The bucket to make into a HEAP bucket + * @param buf The buffer to insert into the bucket + * @param nbyte The size of the buffer to insert. + * @param free_func Function to use to free the data; NULL indicates that the + * bucket should make a copy of the data + * @return The new bucket, or NULL if allocation failed + */ +APU_DECLARE(apr_bucket *) apr_bucket_heap_make(apr_bucket *b, const char *buf, + apr_size_t nbyte, + void (*free_func)(void *data)); + +/** + * Create a bucket referring to memory allocated from a pool. + * + * @param buf The buffer to insert into the bucket + * @param length The number of bytes referred to by this bucket + * @param pool The pool the memory was allocated from + * @param list The freelist from which this bucket should be allocated + * @return The new bucket, or NULL if allocation failed + */ +APU_DECLARE(apr_bucket *) apr_bucket_pool_create(const char *buf, + apr_size_t length, + apr_pool_t *pool, + apr_bucket_alloc_t *list); + +/** + * Make the bucket passed in a bucket refer to pool data + * @param b The bucket to make into a pool bucket + * @param buf The buffer to insert into the bucket + * @param length The number of bytes referred to by this bucket + * @param pool The pool the memory was allocated from + * @return The new bucket, or NULL if allocation failed + */ +APU_DECLARE(apr_bucket *) apr_bucket_pool_make(apr_bucket *b, const char *buf, + apr_size_t length, + apr_pool_t *pool); + +#if APR_HAS_MMAP +/** + * Create a bucket referring to mmap()ed memory. + * @param mm The mmap to insert into the bucket + * @param start The offset of the first byte in the mmap + * that this bucket refers to + * @param length The number of bytes referred to by this bucket + * @param list The freelist from which this bucket should be allocated + * @return The new bucket, or NULL if allocation failed + */ +APU_DECLARE(apr_bucket *) apr_bucket_mmap_create(apr_mmap_t *mm, + apr_off_t start, + apr_size_t length, + apr_bucket_alloc_t *list); + +/** + * Make the bucket passed in a bucket refer to an MMAP'ed file + * @param b The bucket to make into a MMAP bucket + * @param mm The mmap to insert into the bucket + * @param start The offset of the first byte in the mmap + * that this bucket refers to + * @param length The number of bytes referred to by this bucket + * @return The new bucket, or NULL if allocation failed + */ +APU_DECLARE(apr_bucket *) apr_bucket_mmap_make(apr_bucket *b, apr_mmap_t *mm, + apr_off_t start, + apr_size_t length); +#endif + +/** + * Create a bucket referring to a socket. + * @param thissock The socket to put in the bucket + * @param list The freelist from which this bucket should be allocated + * @return The new bucket, or NULL if allocation failed + */ +APU_DECLARE(apr_bucket *) apr_bucket_socket_create(apr_socket_t *thissock, + apr_bucket_alloc_t *list); +/** + * Make the bucket passed in a bucket refer to a socket + * @param b The bucket to make into a SOCKET bucket + * @param thissock The socket to put in the bucket + * @return The new bucket, or NULL if allocation failed + */ +APU_DECLARE(apr_bucket *) apr_bucket_socket_make(apr_bucket *b, + apr_socket_t *thissock); + +/** + * Create a bucket referring to a pipe. + * @param thispipe The pipe to put in the bucket + * @param list The freelist from which this bucket should be allocated + * @return The new bucket, or NULL if allocation failed + */ +APU_DECLARE(apr_bucket *) apr_bucket_pipe_create(apr_file_t *thispipe, + apr_bucket_alloc_t *list); + +/** + * Make the bucket passed in a bucket refer to a pipe + * @param b The bucket to make into a PIPE bucket + * @param thispipe The pipe to put in the bucket + * @return The new bucket, or NULL if allocation failed + */ +APU_DECLARE(apr_bucket *) apr_bucket_pipe_make(apr_bucket *b, + apr_file_t *thispipe); + +/** + * Create a bucket referring to a file. + * @param fd The file to put in the bucket + * @param offset The offset where the data of interest begins in the file + * @param len The amount of data in the file we are interested in + * @param p The pool into which any needed structures should be created + * while reading from this file bucket + * @param list The freelist from which this bucket should be allocated + * @return The new bucket, or NULL if allocation failed + * @remark If the file is truncated such that the segment of the file + * referenced by the bucket no longer exists, an attempt to read + * from the bucket will fail with APR_EOF. + * @remark apr_brigade_insert_file() should generally be used to + * insert files into brigades, since that function can correctly + * handle large file issues. + */ +APU_DECLARE(apr_bucket *) apr_bucket_file_create(apr_file_t *fd, + apr_off_t offset, + apr_size_t len, + apr_pool_t *p, + apr_bucket_alloc_t *list); + +/** + * Make the bucket passed in a bucket refer to a file + * @param b The bucket to make into a FILE bucket + * @param fd The file to put in the bucket + * @param offset The offset where the data of interest begins in the file + * @param len The amount of data in the file we are interested in + * @param p The pool into which any needed structures should be created + * while reading from this file bucket + * @return The new bucket, or NULL if allocation failed + */ +APU_DECLARE(apr_bucket *) apr_bucket_file_make(apr_bucket *b, apr_file_t *fd, + apr_off_t offset, + apr_size_t len, apr_pool_t *p); + +/** + * Enable or disable memory-mapping for a FILE bucket (default is enabled) + * @param b The bucket + * @param enabled Whether memory-mapping should be enabled + * @return APR_SUCCESS normally, or an error code if the operation fails + */ +APU_DECLARE(apr_status_t) apr_bucket_file_enable_mmap(apr_bucket *b, + int enabled); + +/** + * Set the size of the read buffer allocated by a FILE bucket (default + * is @a APR_BUCKET_BUFF_SIZE) + * memory-mapping is disabled only) + * @param b The bucket + * @param size Size of the allocated buffers + * @return APR_SUCCESS normally, or an error code if the operation fails + * @remark Relevant/used only when memory-mapping is disabled (@see + * apr_bucket_file_enable_mmap) + */ +APU_DECLARE(apr_status_t) apr_bucket_file_set_buf_size(apr_bucket *b, + apr_size_t size); + +/** @} */ +#ifdef __cplusplus +} +#endif + +#endif /* !APR_BUCKETS_H */ |