freebsd-skq/contrib/serf/serf.h
2018-10-09 15:28:06 +00:00

1123 lines
38 KiB
C

/* ====================================================================
* 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.
* ====================================================================
*/
#ifndef SERF_H
#define SERF_H
/**
* @file serf.h
* @brief Main serf header file
*/
#include <apr.h>
#include <apr_errno.h>
#include <apr_allocator.h>
#include <apr_pools.h>
#include <apr_network_io.h>
#include <apr_time.h>
#include <apr_poll.h>
#include <apr_uri.h>
#ifdef __cplusplus
extern "C" {
#endif
/* Forward declare some structures */
typedef struct serf_context_t serf_context_t;
typedef struct serf_bucket_t serf_bucket_t;
typedef struct serf_bucket_type_t serf_bucket_type_t;
typedef struct serf_bucket_alloc_t serf_bucket_alloc_t;
typedef struct serf_connection_t serf_connection_t;
typedef struct serf_listener_t serf_listener_t;
typedef struct serf_incoming_t serf_incoming_t;
typedef struct serf_incoming_request_t serf_incoming_request_t;
typedef struct serf_request_t serf_request_t;
/**
* @defgroup serf high-level constructs
* @ingroup serf
* @{
*/
/**
* Serf-specific error codes
*/
#define SERF_ERROR_RANGE 100
#define SERF_ERROR_START (APR_OS_START_USERERR + SERF_ERROR_RANGE)
/* This code is for when this is the last response on this connection:
* i.e. do not send any more requests on this connection or expect
* any more responses.
*/
#define SERF_ERROR_CLOSING (SERF_ERROR_START + 1)
/* This code is for when the connection terminated before the request
* could be processed on the other side.
*/
#define SERF_ERROR_REQUEST_LOST (SERF_ERROR_START + 2)
/* This code is for when the connection is blocked - we can not proceed
* until something happens - generally due to SSL negotiation-like behavior
* where a write() is blocked until a read() is processed.
*/
#define SERF_ERROR_WAIT_CONN (SERF_ERROR_START + 3)
/* This code is for when something went wrong during deflating compressed
* data e.g. a CRC error. */
#define SERF_ERROR_DECOMPRESSION_FAILED (SERF_ERROR_START + 4)
/* This code is for when a response received from a http server is not in
* http-compliant syntax. */
#define SERF_ERROR_BAD_HTTP_RESPONSE (SERF_ERROR_START + 5)
/* The server sent less data than what was announced. */
#define SERF_ERROR_TRUNCATED_HTTP_RESPONSE (SERF_ERROR_START + 6)
/* The proxy server returned an error while setting up the SSL tunnel. */
#define SERF_ERROR_SSLTUNNEL_SETUP_FAILED (SERF_ERROR_START + 7)
/* The server unexpectedly closed the connection prematurely. */
#define SERF_ERROR_ABORTED_CONNECTION (SERF_ERROR_START + 8)
/* SSL certificates related errors */
#define SERF_ERROR_SSL_CERT_FAILED (SERF_ERROR_START + 70)
/* SSL communications related errors */
#define SERF_ERROR_SSL_COMM_FAILED (SERF_ERROR_START + 71)
/* General authentication related errors */
#define SERF_ERROR_AUTHN_FAILED (SERF_ERROR_START + 90)
/* None of the available authn mechanisms for the request are supported */
#define SERF_ERROR_AUTHN_NOT_SUPPORTED (SERF_ERROR_START + 91)
/* Authn was requested by the server but the header lacked some attribute */
#define SERF_ERROR_AUTHN_MISSING_ATTRIBUTE (SERF_ERROR_START + 92)
/* Authentication handler initialization related errors */
#define SERF_ERROR_AUTHN_INITALIZATION_FAILED (SERF_ERROR_START + 93)
/* Error code reserved for use in the test suite. */
#define SERF_ERROR_ISSUE_IN_TESTSUITE (SERF_ERROR_START + 99)
/* This macro groups errors potentially raised when reading a http response. */
#define SERF_BAD_RESPONSE_ERROR(status) ((status) \
&& ((SERF_ERROR_DECOMPRESSION_FAILED == (status)) \
||(SERF_ERROR_BAD_HTTP_RESPONSE == (status)) \
||(SERF_ERROR_TRUNCATED_HTTP_RESPONSE == (status))))
/**
* Return a string that describes the specified error code.
*
* If the error code is not one of the above Serf error codes, then
* NULL will be returned.
*
* Note regarding lifetime: the string is a statically-allocated constant
*/
const char *serf_error_string(apr_status_t errcode);
/**
* Create a new context for serf operations.
*
* A serf context defines a control loop which processes multiple
* connections simultaneously.
*
* The context will be allocated within @a pool.
*/
serf_context_t *serf_context_create(
apr_pool_t *pool);
/**
* Callback function. Add a socket to the externally managed poll set.
*
* Both @a pfd and @a serf_baton should be used when calling serf_event_trigger
* later.
*/
typedef apr_status_t (*serf_socket_add_t)(
void *user_baton,
apr_pollfd_t *pfd,
void *serf_baton);
/**
* Callback function. Remove the socket, identified by both @a pfd and
* @a serf_baton from the externally managed poll set.
*/
typedef apr_status_t (*serf_socket_remove_t)(
void *user_baton,
apr_pollfd_t *pfd,
void *serf_baton);
/* Create a new context for serf operations.
*
* Use this function to make serf not use its internal control loop, but
* instead rely on an external event loop. Serf will use the @a addf and @a rmf
* callbacks to notify of any event on a connection. The @a user_baton will be
* passed through the addf and rmf callbacks.
*
* The context will be allocated within @a pool.
*/
serf_context_t *serf_context_create_ex(
void *user_baton,
serf_socket_add_t addf,
serf_socket_remove_t rmf,
apr_pool_t *pool);
/**
* Make serf process events on a connection, identified by both @a pfd and
* @a serf_baton.
*
* Any outbound data is delivered, and incoming data is made available to
* the associated response handlers and their buckets.
*
* If any data is processed (incoming or outgoing), then this function will
* return with APR_SUCCESS.
*/
apr_status_t serf_event_trigger(
serf_context_t *s,
void *serf_baton,
const apr_pollfd_t *pfd);
/** @see serf_context_run should not block at all. */
#define SERF_DURATION_NOBLOCK 0
/** @see serf_context_run should run for (nearly) "forever". */
#define SERF_DURATION_FOREVER 2000000000 /* approx 1^31 */
/**
* Run the main networking control loop.
*
* The set of connections defined by the serf context @a ctx are processed.
* Any outbound data is delivered, and incoming data is made available to
* the associated response handlers and their buckets. This function will
* block on the network for no longer than @a duration microseconds.
*
* If any data is processed (incoming or outgoing), then this function will
* return with APR_SUCCESS. Typically, the caller will just want to call it
* again to continue processing data.
*
* If no activity occurs within the specified timeout duration, then
* APR_TIMEUP is returned.
*
* All temporary allocations will be made in @a pool.
*/
apr_status_t serf_context_run(
serf_context_t *ctx,
apr_short_interval_time_t duration,
apr_pool_t *pool);
apr_status_t serf_context_prerun(
serf_context_t *ctx);
/**
* Callback function for progress information. @a progress indicates cumulative
* number of bytes read or written, for the whole context.
*/
typedef void (*serf_progress_t)(
void *progress_baton,
apr_off_t read,
apr_off_t write);
/**
* Sets the progress callback function. @a progress_func will be called every
* time bytes are read of or written on a socket.
*/
void serf_context_set_progress_cb(
serf_context_t *ctx,
const serf_progress_t progress_func,
void *progress_baton);
/** @} */
/**
* @defgroup serf connections and requests
* @ingroup serf
* @{
*/
/**
* When a connection is established, the application needs to wrap some
* buckets around @a skt to enable serf to process incoming responses. This
* is the control point for assembling connection-level processing logic
* around the given socket.
*
* The @a setup_baton is the baton established at connection creation time.
*
* This callback corresponds to reading from the server. Since this is an
* on-demand activity, we use a callback. The corresponding write operation
* is based on the @see serf_request_deliver function, where the application
* can assemble the appropriate bucket(s) before delivery.
*
* The returned bucket should live at least as long as the connection itself.
* It is assumed that an appropriate allocator is passed in @a setup_baton.
* ### we may want to create a connection-level allocator and pass that
* ### along. however, that allocator would *only* be used for this
* ### callback. it may be wasteful to create a per-conn allocator, so this
* ### baton-based, app-responsible form might be best.
*
* Responsibility for the buckets is passed to the serf library. They will be
* destroyed when the connection is closed.
*
* All temporary allocations should be made in @a pool.
*/
typedef apr_status_t (*serf_connection_setup_t)(
apr_socket_t *skt,
serf_bucket_t **read_bkt,
serf_bucket_t **write_bkt,
void *setup_baton,
apr_pool_t *pool);
/**
* ### need to update docco w.r.t socket. became "stream" recently.
* ### the stream does not have a barrier, this callback should generally
* ### add a barrier around the stream before incorporating it into a
* ### response bucket stack.
* ### should serf add the barrier automatically to protect its data
* ### structure? i.e. the passed bucket becomes owned rather than
* ### borrowed. that might suit overall semantics better.
* Accept an incoming response for @a request, and its @a socket. A bucket
* for the response should be constructed and returned. This is the control
* point for assembling the appropriate wrapper buckets around the socket to
* enable processing of the incoming response.
*
* The @a acceptor_baton is the baton provided when the specified request
* was created.
*
* The request's pool and bucket allocator should be used for any allocations
* that need to live for the duration of the response. Care should be taken
* to bound the amount of memory stored in this pool -- to ensure that
* allocations are not proportional to the amount of data in the response.
*
* Responsibility for the bucket is passed to the serf library. It will be
* destroyed when the response has been fully read (the bucket returns an
* APR_EOF status from its read functions).
*
* All temporary allocations should be made in @a pool.
*/
/* ### do we need to return an error? */
typedef serf_bucket_t * (*serf_response_acceptor_t)(
serf_request_t *request,
serf_bucket_t *stream,
void *acceptor_baton,
apr_pool_t *pool);
/**
* Notification callback for when a connection closes.
*
* This callback is used to inform an application that the @a conn
* connection has been (abnormally) closed. The @a closed_baton is the
* baton provided when the connection was first opened. The reason for
* closure is given in @a why, and will be APR_SUCCESS if the application
* requested closure (by clearing the pool used to allocate this
* connection or calling serf_connection_close).
*
* All temporary allocations should be made in @a pool.
*/
typedef void (*serf_connection_closed_t)(
serf_connection_t *conn,
void *closed_baton,
apr_status_t why,
apr_pool_t *pool);
/**
* Response data has arrived and should be processed.
*
* Whenever response data for @a request arrives (initially, or continued data
* arrival), this handler is invoked. The response data is available in the
* @a response bucket. The @a handler_baton is passed along from the baton
* provided by the request setup callback (@see serf_request_setup_t).
*
* The handler MUST process data from the @a response bucket until the
* bucket's read function states it would block (see APR_STATUS_IS_EAGAIN).
* The handler is invoked only when new data arrives. If no further data
* arrives, and the handler does not process all available data, then the
* system can result in a deadlock around the unprocessed, but read, data.
*
* The handler should return APR_EOF when the response has been fully read.
* If calling the handler again would block, APR_EAGAIN should be returned.
* If the handler should be invoked again, simply return APR_SUCCESS.
*
* Note: if the connection closed (at the request of the application, or
* because of an (abnormal) termination) while a request is being delivered,
* or before a response arrives, then @a response will be NULL. This is the
* signal that the request was not delivered properly, and no further
* response should be expected (this callback will not be invoked again).
* If a request is injected into the connection (during this callback's
* execution, or otherwise), then the connection will be reopened.
*
* All temporary allocations should be made in @a pool.
*/
typedef apr_status_t (*serf_response_handler_t)(
serf_request_t *request,
serf_bucket_t *response,
void *handler_baton,
apr_pool_t *pool);
/**
* Callback function to be implemented by the application, so that serf
* can handle server and proxy authentication.
* code = 401 (server) or 407 (proxy).
* baton = the baton passed to serf_context_run.
* authn_type = one of "Basic", "Digest".
*/
typedef apr_status_t (*serf_credentials_callback_t)(
char **username,
char **password,
serf_request_t *request, void *baton,
int code, const char *authn_type,
const char *realm,
apr_pool_t *pool);
/**
* Create a new connection associated with the @a ctx serf context.
*
* If no proxy server is configured, a connection will be created to
* (eventually) connect to the address specified by @a address. The address must
* live at least as long as @a pool (thus, as long as the connection object).
* If a proxy server is configured, @address will be ignored.
*
* The connection object will be allocated within @a pool. Clearing or
* destroying this pool will close the connection, and terminate any
* outstanding requests or responses.
*
* When the connection is closed (upon request or because of an error),
* then the @a closed callback is invoked, and @a closed_baton is passed.
*
* ### doc on setup(_baton). tweak below comment re: acceptor.
* NULL may be passed for @a acceptor and @a closed; default implementations
* will be used.
*
* Note: the connection is not made immediately. It will be opened on
* the next call to @see serf_context_run.
*/
serf_connection_t *serf_connection_create(
serf_context_t *ctx,
apr_sockaddr_t *address,
serf_connection_setup_t setup,
void *setup_baton,
serf_connection_closed_t closed,
void *closed_baton,
apr_pool_t *pool);
/**
* Create a new connection associated with the @a ctx serf context.
*
* A connection will be created to (eventually) connect to the address
* specified by @a address. The address must live at least as long as
* @a pool (thus, as long as the connection object).
*
* The host address will be looked up based on the hostname in @a host_info.
*
* The connection object will be allocated within @a pool. Clearing or
* destroying this pool will close the connection, and terminate any
* outstanding requests or responses.
*
* When the connection is closed (upon request or because of an error),
* then the @a closed callback is invoked, and @a closed_baton is passed.
*
* ### doc on setup(_baton). tweak below comment re: acceptor.
* NULL may be passed for @a acceptor and @a closed; default implementations
* will be used.
*
* Note: the connection is not made immediately. It will be opened on
* the next call to @see serf_context_run.
*/
apr_status_t serf_connection_create2(
serf_connection_t **conn,
serf_context_t *ctx,
apr_uri_t host_info,
serf_connection_setup_t setup,
void *setup_baton,
serf_connection_closed_t closed,
void *closed_baton,
apr_pool_t *pool);
typedef apr_status_t (*serf_accept_client_t)(
serf_context_t *ctx,
serf_listener_t *l,
void *accept_baton,
apr_socket_t *insock,
apr_pool_t *pool);
apr_status_t serf_listener_create(
serf_listener_t **listener,
serf_context_t *ctx,
const char *host,
apr_uint16_t port,
void *accept_baton,
serf_accept_client_t accept_func,
apr_pool_t *pool);
typedef apr_status_t (*serf_incoming_request_cb_t)(
serf_context_t *ctx,
serf_incoming_request_t *req,
void *request_baton,
apr_pool_t *pool);
apr_status_t serf_incoming_create(
serf_incoming_t **client,
serf_context_t *ctx,
apr_socket_t *insock,
void *request_baton,
serf_incoming_request_cb_t request,
apr_pool_t *pool);
/**
* Reset the connection, but re-open the socket again.
*/
apr_status_t serf_connection_reset(
serf_connection_t *conn);
/**
* Close the connection associated with @a conn and cancel all pending requests.
*
* The closed callback passed to serf_connection_create() will be invoked
* with APR_SUCCESS.
*/
apr_status_t serf_connection_close(
serf_connection_t *conn);
/**
* Sets the maximum number of outstanding requests @a max_requests on the
* connection @a conn. Setting max_requests to 0 means unlimited (the default).
* Ex.: setting max_requests to 1 means a request is sent when a response on the
* previous request was received and handled.
*
* In general, serf tends to take around 16KB per outstanding request.
*/
void serf_connection_set_max_outstanding_requests(
serf_connection_t *conn,
unsigned int max_requests);
void serf_connection_set_async_responses(
serf_connection_t *conn,
serf_response_acceptor_t acceptor,
void *acceptor_baton,
serf_response_handler_t handler,
void *handler_baton);
/**
* Setup the @a request for delivery on its connection.
*
* Right before this is invoked, @a pool will be built within the
* connection's pool for the request to use. The associated response will
* be allocated within that subpool. An associated bucket allocator will
* be built. These items may be fetched from the request object through
* @see serf_request_get_pool or @see serf_request_get_alloc.
*
* The content of the request is specified by the @a req_bkt bucket. When
* a response arrives, the @a acceptor callback will be invoked (along with
* the @a acceptor_baton) to produce a response bucket. That bucket will then
* be passed to @a handler, along with the @a handler_baton.
*
* The responsibility for the request bucket is passed to the request
* object. When the request is done with the bucket, it will be destroyed.
*/
typedef apr_status_t (*serf_request_setup_t)(
serf_request_t *request,
void *setup_baton,
serf_bucket_t **req_bkt,
serf_response_acceptor_t *acceptor,
void **acceptor_baton,
serf_response_handler_t *handler,
void **handler_baton,
apr_pool_t *pool);
/**
* Construct a request object for the @a conn connection.
*
* When it is time to deliver the request, the @a setup callback will
* be invoked with the @a setup_baton passed into it to complete the
* construction of the request object.
*
* If the request has not (yet) been delivered, then it may be canceled
* with @see serf_request_cancel.
*
* Invoking any calls other than @see serf_request_cancel before the setup
* callback executes is not supported.
*/
serf_request_t *serf_connection_request_create(
serf_connection_t *conn,
serf_request_setup_t setup,
void *setup_baton);
/**
* Construct a request object for the @a conn connection, add it in the
* list as the next to-be-written request before all unwritten requests.
*
* When it is time to deliver the request, the @a setup callback will
* be invoked with the @a setup_baton passed into it to complete the
* construction of the request object.
*
* If the request has not (yet) been delivered, then it may be canceled
* with @see serf_request_cancel.
*
* Invoking any calls other than @see serf_request_cancel before the setup
* callback executes is not supported.
*/
serf_request_t *serf_connection_priority_request_create(
serf_connection_t *conn,
serf_request_setup_t setup,
void *setup_baton);
/** Returns detected network latency for the @a conn connection. Negative
* value means that latency is unknwon.
*/
apr_interval_time_t serf_connection_get_latency(serf_connection_t *conn);
/** Check if a @a request has been completely written.
*
* Returns APR_SUCCESS if the request was written completely on the connection.
* Returns APR_EBUSY if the request is not yet or partially written.
*/
apr_status_t serf_request_is_written(
serf_request_t *request);
/**
* Cancel the request specified by the @a request object.
*
* If the request has been scheduled for delivery, then its response
* handler will be run, passing NULL for the response bucket.
*
* If the request has already been (partially or fully) delivered, then
* APR_EBUSY is returned and the request is *NOT* canceled. To properly
* cancel the request, the connection must be closed (by clearing or
* destroying its associated pool).
*/
apr_status_t serf_request_cancel(
serf_request_t *request);
/**
* Return the pool associated with @a request.
*
* WARNING: be very careful about the kinds of things placed into this
* pool. In particular, all allocation should be bounded in size, rather
* than proportional to any data stream.
*/
apr_pool_t *serf_request_get_pool(
const serf_request_t *request);
/**
* Return the bucket allocator associated with @a request.
*/
serf_bucket_alloc_t *serf_request_get_alloc(
const serf_request_t *request);
/**
* Return the connection associated with @a request.
*/
serf_connection_t *serf_request_get_conn(
const serf_request_t *request);
/**
* Update the @a handler and @a handler_baton for this @a request.
*
* This can be called after the request has started processing -
* subsequent data will be delivered to this new handler.
*/
void serf_request_set_handler(
serf_request_t *request,
const serf_response_handler_t handler,
const void **handler_baton);
/**
* Configure proxy server settings, to be used by all connections associated
* with the @a ctx serf context.
*
* The next connection will be created to connect to the proxy server
* specified by @a address. The address must live at least as long as the
* serf context.
*/
void serf_config_proxy(
serf_context_t *ctx,
apr_sockaddr_t *address);
/* Supported authentication types. */
#define SERF_AUTHN_NONE 0x00
#define SERF_AUTHN_BASIC 0x01
#define SERF_AUTHN_DIGEST 0x02
#define SERF_AUTHN_NTLM 0x04
#define SERF_AUTHN_NEGOTIATE 0x08
#define SERF_AUTHN_ALL 0xFF
/**
* Define the authentication handlers that serf will try on incoming requests.
*/
void serf_config_authn_types(
serf_context_t *ctx,
int authn_types);
/**
* Set the credentials callback handler.
*/
void serf_config_credentials_callback(
serf_context_t *ctx,
serf_credentials_callback_t cred_cb);
/* ### maybe some connection control functions for flood? */
/*** Special bucket creation functions ***/
/**
* Create a bucket of type 'socket bucket'.
* This is basically a wrapper around @a serf_bucket_socket_create, which
* initializes the bucket using connection and/or context specific settings.
*/
serf_bucket_t *serf_context_bucket_socket_create(
serf_context_t *ctx,
apr_socket_t *skt,
serf_bucket_alloc_t *allocator);
/**
* Create a bucket of type 'request bucket'.
* This is basically a wrapper around @a serf_bucket_request_create, which
* initializes the bucket using request, connection and/or context specific
* settings.
*
* This function will set following header(s):
* - Host: if the connection was created with @a serf_connection_create2.
*/
serf_bucket_t *serf_request_bucket_request_create(
serf_request_t *request,
const char *method,
const char *uri,
serf_bucket_t *body,
serf_bucket_alloc_t *allocator);
/** @} */
/**
* @defgroup serf buckets
* @ingroup serf
* @{
*/
/** Pass as REQUESTED to the read function of a bucket to read, consume,
* and return all available data.
*/
#define SERF_READ_ALL_AVAIL ((apr_size_t)-1)
/** Acceptable newline types for bucket->readline(). */
#define SERF_NEWLINE_CR 0x0001
#define SERF_NEWLINE_CRLF 0x0002
#define SERF_NEWLINE_LF 0x0004
#define SERF_NEWLINE_ANY 0x0007
/** Used to indicate that a newline is not present in the data buffer. */
/* ### should we make this zero? */
#define SERF_NEWLINE_NONE 0x0008
/** Used to indicate that a CR was found at the end of a buffer, and CRLF
* was acceptable. It may be that the LF is present, but it needs to be
* read first.
*
* Note: an alternative to using this symbol would be for callers to see
* the SERF_NEWLINE_CR return value, and know that some "end of buffer" was
* reached. While this works well for @see serf_util_readline, it does not
* necessary work as well for buckets (there is no obvious "end of buffer",
* although there is an "end of bucket"). The other problem with that
* alternative is that developers might miss the condition. This symbol
* calls out the possibility and ensures that callers will watch for it.
*/
#define SERF_NEWLINE_CRLF_SPLIT 0x0010
struct serf_bucket_type_t {
/** name of this bucket type */
const char *name;
/**
* Read (and consume) up to @a requested bytes from @a bucket.
*
* A pointer to the data will be returned in @a data, and its length
* is specified by @a len.
*
* The data will exist until one of two conditions occur:
*
* 1) this bucket is destroyed
* 2) another call to any read function or to peek()
*
* If an application needs the data to exist for a longer duration,
* then it must make a copy.
*/
apr_status_t (*read)(serf_bucket_t *bucket, apr_size_t requested,
const char **data, apr_size_t *len);
/**
* Read (and consume) a line of data from @a bucket.
*
* The acceptable forms of a newline are given by @a acceptable, and
* the type found is returned in @a found. If a newline is not present
* in the returned data, then SERF_NEWLINE_NONE is stored into @a found.
*
* A pointer to the data is returned in @a data, and its length is
* specified by @a len. The data will include the newline, if present.
*
* Note that there is no way to limit the amount of data returned
* by this function.
*
* The lifetime of the data is the same as that of the @see read
* function above.
*/
apr_status_t (*readline)(serf_bucket_t *bucket, int acceptable,
int *found,
const char **data, apr_size_t *len);
/**
* Read a set of pointer/length pairs from the bucket.
*
* The size of the @a vecs array is specified by @a vecs_size. The
* bucket should fill in elements of the array, and return the number
* used in @a vecs_used.
*
* Each element of @a vecs should specify a pointer to a block of
* data and a length of that data.
*
* The total length of all data elements should not exceed the
* amount specified in @a requested.
*
* The lifetime of the data is the same as that of the @see read
* function above.
*/
apr_status_t (*read_iovec)(serf_bucket_t *bucket, apr_size_t requested,
int vecs_size, struct iovec *vecs,
int *vecs_used);
/**
* Read data from the bucket in a form suitable for apr_socket_sendfile()
*
* On input, hdtr->numheaders and hdtr->numtrailers specify the size
* of the hdtr->headers and hdtr->trailers arrays, respectively. The
* bucket should fill in the headers and trailers, up to the specified
* limits, and set numheaders and numtrailers to the number of iovecs
* filled in for each item.
*
* @a file should be filled in with a file that can be read. If a file
* is not available or appropriate, then NULL should be stored. The
* file offset for the data should be stored in @a offset, and the
* length of that data should be stored in @a len. If a file is not
* returned, then @a offset and @a len should be ignored.
*
* The file position is not required to correspond to @a offset, and
* the caller may manipulate it at will.
*
* The total length of all data elements, and the portion of the
* file should not exceed the amount specified in @a requested.
*
* The lifetime of the data is the same as that of the @see read
* function above.
*/
apr_status_t (*read_for_sendfile)(serf_bucket_t *bucket,
apr_size_t requested, apr_hdtr_t *hdtr,
apr_file_t **file, apr_off_t *offset,
apr_size_t *len);
/**
* Look within @a bucket for a bucket of the given @a type. The bucket
* must be the "initial" data because it will be consumed by this
* function. If the given bucket type is available, then read and consume
* it, and return it to the caller.
*
* This function is usually used by readers that have custom handling
* for specific bucket types (e.g. looking for a file bucket to pass
* to apr_socket_sendfile).
*
* If a bucket of the given type is not found, then NULL is returned.
*
* The returned bucket becomes the responsibility of the caller. When
* the caller is done with the bucket, it should be destroyed.
*/
serf_bucket_t * (*read_bucket)(serf_bucket_t *bucket,
const serf_bucket_type_t *type);
/**
* Peek, but don't consume, the data in @a bucket.
*
* Since this function is non-destructive, the implicit read size is
* SERF_READ_ALL_AVAIL. The caller can then use whatever amount is
* appropriate.
*
* The @a data parameter will point to the data, and @a len will
* specify how much data is available. The lifetime of the data follows
* the same rules as the @see read function above.
*
* Note: if the peek does not return enough data for your particular
* use, then you must read/consume some first, then peek again.
*
* If the returned data represents all available data, then APR_EOF
* will be returned. Since this function does not consume data, it
* can return the same data repeatedly rather than blocking; thus,
* APR_EAGAIN will never be returned.
*/
apr_status_t (*peek)(serf_bucket_t *bucket,
const char **data, apr_size_t *len);
/**
* Destroy @a bucket, along with any associated resources.
*/
void (*destroy)(serf_bucket_t *bucket);
/* ### apr buckets have 'copy', 'split', and 'setaside' functions.
### not sure whether those will be needed in this bucket model.
*/
};
/**
* Should the use and lifecycle of buckets be tracked?
*
* When tracking, the system will ensure several semantic requirements
* of bucket use:
*
* - if a bucket returns APR_EAGAIN, one of its read functions should
* not be called immediately. the context's run loop should be called.
* ### and for APR_EOF, too?
* - all buckets must be drained of input before returning to the
* context's run loop.
* - buckets should not be destroyed before they return APR_EOF unless
* the connection is closed for some reason.
*
* Undefine this symbol to avoid the tracking (and a performance gain).
*
* ### we may want to examine when/how we provide this. should it always
* ### be compiled in? and apps select it before including this header?
*/
/* #define SERF_DEBUG_BUCKET_USE */
/* Internal macros for tracking bucket use. */
#ifdef SERF_DEBUG_BUCKET_USE
#define SERF__RECREAD(b,s) serf_debug__record_read(b,s)
#else
#define SERF__RECREAD(b,s) (s)
#endif
#define serf_bucket_read(b,r,d,l) SERF__RECREAD(b, (b)->type->read(b,r,d,l))
#define serf_bucket_readline(b,a,f,d,l) \
SERF__RECREAD(b, (b)->type->readline(b,a,f,d,l))
#define serf_bucket_read_iovec(b,r,s,v,u) \
SERF__RECREAD(b, (b)->type->read_iovec(b,r,s,v,u))
#define serf_bucket_read_for_sendfile(b,r,h,f,o,l) \
SERF__RECREAD(b, (b)->type->read_for_sendfile(b,r,h,f,o,l))
#define serf_bucket_read_bucket(b,t) ((b)->type->read_bucket(b,t))
#define serf_bucket_peek(b,d,l) ((b)->type->peek(b,d,l))
#define serf_bucket_destroy(b) ((b)->type->destroy(b))
/**
* Check whether a real error occurred. Note that bucket read functions
* can return EOF and EAGAIN as part of their "normal" operation, so they
* should not be considered an error.
*/
#define SERF_BUCKET_READ_ERROR(status) ((status) \
&& !APR_STATUS_IS_EOF(status) \
&& !APR_STATUS_IS_EAGAIN(status) \
&& (SERF_ERROR_WAIT_CONN != status))
struct serf_bucket_t {
/** the type of this bucket */
const serf_bucket_type_t *type;
/** bucket-private data */
void *data;
/** the allocator used for this bucket (needed at destroy time) */
serf_bucket_alloc_t *allocator;
};
/**
* Generic macro to construct "is TYPE" macros.
*/
#define SERF_BUCKET_CHECK(b, btype) ((b)->type == &serf_bucket_type_ ## btype)
/**
* Notification callback for a block that was not returned to the bucket
* allocator when its pool was destroyed.
*
* The block of memory is given by @a block. The baton provided when the
* allocator was constructed is passed as @a unfreed_baton.
*/
typedef void (*serf_unfreed_func_t)(
void *unfreed_baton,
void *block);
/**
* Create a new allocator for buckets.
*
* All buckets are associated with a serf bucket allocator. This allocator
* will be created within @a pool and will be destroyed when that pool is
* cleared or destroyed.
*
* When the allocator is destroyed, if any allocations were not explicitly
* returned (by calling serf_bucket_mem_free), then the @a unfreed callback
* will be invoked for each block. @a unfreed_baton will be passed to the
* callback.
*
* If @a unfreed is NULL, then the library will invoke the abort() stdlib
* call. Any failure to return memory is a bug in the application, and an
* abort can assist with determining what kinds of memory were not freed.
*/
serf_bucket_alloc_t *serf_bucket_allocator_create(
apr_pool_t *pool,
serf_unfreed_func_t unfreed,
void *unfreed_baton);
/**
* Return the pool that was used for this @a allocator.
*
* WARNING: the use of this pool for allocations requires a very
* detailed understanding of pool behaviors, the bucket system,
* and knowledge of the bucket's use within the overall pattern
* of request/response behavior.
*
* See design-guide.txt for more information about pool usage.
*/
apr_pool_t *serf_bucket_allocator_get_pool(
const serf_bucket_alloc_t *allocator);
/**
* Utility structure for reading a complete line of input from a bucket.
*
* Since it is entirely possible for a line to be broken by APR_EAGAIN,
* this structure can be used to accumulate the data until a complete line
* has been read from a bucket.
*/
/* This limit applies to the line buffer functions. If an application needs
* longer lines, then they will need to manually handle line buffering.
*/
#define SERF_LINEBUF_LIMIT 8000
typedef struct {
/* Current state of the buffer. */
enum {
SERF_LINEBUF_EMPTY,
SERF_LINEBUF_READY,
SERF_LINEBUF_PARTIAL,
SERF_LINEBUF_CRLF_SPLIT
} state;
/* How much of the buffer have we used? */
apr_size_t used;
/* The line is read into this buffer, minus CR/LF */
char line[SERF_LINEBUF_LIMIT];
} serf_linebuf_t;
/**
* Initialize the @a linebuf structure.
*/
void serf_linebuf_init(serf_linebuf_t *linebuf);
/**
* Fetch a line of text from @a bucket, accumulating the line into
* @a linebuf. @a acceptable specifies the types of newlines which are
* acceptable for this fetch.
*
* ### we should return a data/len pair so that we can avoid a copy,
* ### rather than having callers look into our state and line buffer.
*/
apr_status_t serf_linebuf_fetch(
serf_linebuf_t *linebuf,
serf_bucket_t *bucket,
int acceptable);
/** @} */
/* Internal functions for bucket use and lifecycle tracking */
apr_status_t serf_debug__record_read(
const serf_bucket_t *bucket,
apr_status_t status);
void serf_debug__entered_loop(
serf_bucket_alloc_t *allocator);
void serf_debug__closed_conn(
serf_bucket_alloc_t *allocator);
void serf_debug__bucket_destroy(
const serf_bucket_t *bucket);
void serf_debug__bucket_alloc_check(
serf_bucket_alloc_t *allocator);
/* Version info */
#define SERF_MAJOR_VERSION 1
#define SERF_MINOR_VERSION 3
#define SERF_PATCH_VERSION 9
/* Version number string */
#define SERF_VERSION_STRING APR_STRINGIFY(SERF_MAJOR_VERSION) "." \
APR_STRINGIFY(SERF_MINOR_VERSION) "." \
APR_STRINGIFY(SERF_PATCH_VERSION)
/**
* Check at compile time if the Serf version is at least a certain
* level.
* @param major The major version component of the version checked
* for (e.g., the "1" of "1.3.0").
* @param minor The minor version component of the version checked
* for (e.g., the "3" of "1.3.0").
* @param patch The patch level component of the version checked
* for (e.g., the "0" of "1.3.0").
*/
#define SERF_VERSION_AT_LEAST(major,minor,patch) \
(((major) < SERF_MAJOR_VERSION) \
|| ((major) == SERF_MAJOR_VERSION && (minor) < SERF_MINOR_VERSION) \
|| ((major) == SERF_MAJOR_VERSION && (minor) == SERF_MINOR_VERSION && \
(patch) <= SERF_PATCH_VERSION))
/**
* Returns the version of the library the application has linked/loaded.
* Values are returned in @a major, @a minor, and @a patch.
*
* Applications will want to use this function to verify compatibility,
* expecially while serf has not reached a 1.0 milestone. APIs and
* semantics may change drastically until the library hits 1.0.
*/
void serf_lib_version(
int *major,
int *minor,
int *patch);
#ifdef __cplusplus
}
#endif
/*
* Every user of serf will want to deal with our various bucket types.
* Go ahead and include that header right now.
*
* Note: make sure this occurs outside of the C++ namespace block
*/
#include "serf_bucket_types.h"
#endif /* !SERF_H */