Adding upstream version 2.4.56.upstream/2.4.56

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1119 insertions, 0 deletions

diff --git a/include/http_protocol.h b/include/http_protocol.h
new file mode 100644
index 0000000..94c481e
--- /dev/null
+++ b/include/http_protocol.h
@@ -0,0 +1,1119 @@
+/* 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  http_protocol.h
+ * @brief HTTP protocol handling
+ *
+ * @defgroup APACHE_CORE_PROTO HTTP Protocol Handling
+ * @ingroup  APACHE_CORE
+ * @{
+ */
+
+#ifndef APACHE_HTTP_PROTOCOL_H
+#define APACHE_HTTP_PROTOCOL_H
+
+#include "httpd.h"
+#include "apr_portable.h"
+#include "apr_mmap.h"
+#include "apr_buckets.h"
+#include "util_filter.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * This hook allows modules to insert filters for the current error response
+ * @param r the current request
+ * @ingroup hooks
+ */
+AP_DECLARE_HOOK(void,insert_error_filter,(request_rec *r))
+
+/** This is an optimization.  We keep a record of the filter_rec that
+ * stores the old_write filter, so that we can avoid strcmp's later.
+ */
+AP_DECLARE_DATA extern ap_filter_rec_t *ap_old_write_func;
+
+/*
+ * Prototypes for routines which either talk directly back to the user,
+ * or control the ones that eventually do.
+ */
+
+/**
+ * Read an empty request and set reasonable defaults.
+ * @param c The current connection
+ * @return The new request_rec
+ */
+AP_DECLARE(request_rec *) ap_create_request(conn_rec *c);
+
+/**
+ * Read a request and fill in the fields.
+ * @param c The current connection
+ * @return The new request_rec
+ */
+request_rec *ap_read_request(conn_rec *c);
+
+/**
+ * Parse and validate the request line.
+ * @param r The current request
+ * @return 1 on success, 0 on failure
+ */
+AP_DECLARE(int) ap_parse_request_line(request_rec *r);
+
+/**
+ * Validate the request header and select vhost.
+ * @param r The current request
+ * @return 1 on success, 0 on failure
+ */
+AP_DECLARE(int) ap_check_request_header(request_rec *r);
+
+/**
+ * Read the mime-encoded headers.
+ * @param r The current request
+ */
+AP_DECLARE(void) ap_get_mime_headers(request_rec *r);
+
+/**
+ * Optimized version of ap_get_mime_headers() that requires a
+ * temporary brigade to work with
+ * @param r The current request
+ * @param bb temp brigade
+ */
+AP_DECLARE(void) ap_get_mime_headers_core(request_rec *r,
+                                          apr_bucket_brigade *bb);
+
+/**
+ * Run post_read_request hook and validate.
+ * @param r The current request
+ * @return OK or HTTP_...
+ */
+AP_DECLARE(int) ap_post_read_request(request_rec *r);
+
+/* Finish up stuff after a request */
+
+/**
+ * Called at completion of sending the response.  It sends the terminating
+ * protocol information.
+ * @param r The current request
+ */
+AP_DECLARE(void) ap_finalize_request_protocol(request_rec *r);
+
+/**
+ * Send error back to client.
+ * @param r The current request
+ * @param recursive_error last arg indicates error status in case we get
+ *      an error in the process of trying to deal with an ErrorDocument
+ *      to handle some other error.  In that case, we print the default
+ *      report for the first thing that went wrong, and more briefly report
+ *      on the problem with the ErrorDocument.
+ */
+AP_DECLARE(void) ap_send_error_response(request_rec *r, int recursive_error);
+
+/* Set last modified header line from the lastmod date of the associated file.
+ * Also, set content length.
+ *
+ * May return an error status, typically HTTP_NOT_MODIFIED (that when the
+ * permit_cache argument is set to one).
+ */
+
+/**
+ * Set the content length for this request
+ * @param r The current request
+ * @param length The new content length
+ */
+AP_DECLARE(void) ap_set_content_length(request_rec *r, apr_off_t length);
+
+/**
+ * Set the keepalive status for this request
+ * @param r The current request
+ * @return 1 if keepalive can be set, 0 otherwise
+ */
+AP_DECLARE(int) ap_set_keepalive(request_rec *r);
+
+/**
+ * Return the latest rational time from a request/mtime pair.  Mtime is
+ * returned unless it's in the future, in which case we return the current time.
+ * @param r The current request
+ * @param mtime The last modified time
+ * @return the latest rational time.
+ */
+AP_DECLARE(apr_time_t) ap_rationalize_mtime(request_rec *r, apr_time_t mtime);
+
+/**
+ * Build the content-type that should be sent to the client from the
+ * content-type specified.  The following rules are followed:
+ *    - if type is NULL or "", return NULL (do not set content-type).
+ *    - if charset adding is disabled, stop processing and return type.
+ *    - then, if there are no parameters on type, add the default charset
+ *    - return type
+ * @param r The current request
+ * @param type The content type
+ * @return The content-type
+ */
+AP_DECLARE(const char *) ap_make_content_type(request_rec *r,
+                                              const char *type);
+
+/**
+ * Precompile metadata structures used by ap_make_content_type()
+ * @param pool The pool to use for allocations
+ */
+AP_DECLARE(void) ap_setup_make_content_type(apr_pool_t *pool);
+
+/** A structure with the ingredients for a file based etag */
+typedef struct etag_rec etag_rec;
+
+/**
+ * @brief A structure with the ingredients for a file based etag
+ */
+struct etag_rec {
+    /** Optional vary list validator */
+    const char *vlist_validator;
+    /** Time when the request started */
+    apr_time_t request_time;
+    /** finfo.protection (st_mode) set to zero if no such file */
+    apr_finfo_t *finfo;
+    /** File pathname used when generating a digest */
+    const char *pathname;
+    /** File descriptor used when generating a digest */
+    apr_file_t *fd;
+    /** Force a non-digest etag to be weak */
+    int force_weak;
+};
+
+/**
+ * Construct an entity tag from the resource information.  If it's a real
+ * file, build in some of the file characteristics.
+ * @param r The current request
+ * @param force_weak Force the entity tag to be weak - it could be modified
+ *                   again in as short an interval.
+ * @return The entity tag
+ */
+AP_DECLARE(char *) ap_make_etag(request_rec *r, int force_weak);
+
+/**
+ * Construct an entity tag from information provided in the etag_rec
+ * structure.
+ * @param r The current request
+ * @param er The etag record, containing ingredients for the etag.
+ */
+AP_DECLARE(char *) ap_make_etag_ex(request_rec *r, etag_rec *er);
+
+/**
+ * Set the E-tag outgoing header
+ * @param r The current request
+ */
+AP_DECLARE(void) ap_set_etag(request_rec *r);
+
+/**
+ * Set the E-tag outgoing header, with the option of forcing a strong ETag.
+ * @param r The current request
+ * @param fd The file descriptor
+ */
+AP_DECLARE(void) ap_set_etag_fd(request_rec *r, apr_file_t *fd);
+
+/**
+ * Set the last modified time for the file being sent
+ * @param r The current request
+ */
+AP_DECLARE(void) ap_set_last_modified(request_rec *r);
+
+typedef enum {
+    AP_CONDITION_NONE,
+    AP_CONDITION_NOMATCH,
+    AP_CONDITION_WEAK,
+    AP_CONDITION_STRONG
+} ap_condition_e;
+
+/**
+ * Tests conditional request rules for the If-Match header.
+ * @param r The current request
+ * @param headers The response headers to check against
+ * @return AP_CONDITION_NONE if the header is missing, AP_CONDITION_NOMATCH
+ *         if the header does not match, AP_CONDITION_STRONG for a strong
+ *         match. Weak matches are not permitted for the If-Match header.
+ */
+AP_DECLARE(ap_condition_e) ap_condition_if_match(request_rec *r,
+        apr_table_t *headers);
+
+/**
+ * Tests conditional request rules for the If-Unmodified-Since header.
+ * @param r The current request
+ * @param headers The response headers to check against
+ * @return AP_CONDITION_NONE if the header is missing, AP_CONDITION_NOMATCH
+ *         if the header does not match, AP_CONDITION_WEAK if a weak match
+ *         was present and allowed by RFC2616, AP_CONDITION_STRONG for a
+ *         strong match.
+ */
+AP_DECLARE(ap_condition_e) ap_condition_if_unmodified_since(request_rec *r,
+        apr_table_t *headers);
+
+/**
+ * Tests conditional request rules for the If-None-Match header.
+ * @param r The current request
+ * @param headers The response headers to check against
+ * @return AP_CONDITION_NONE if the header is missing, AP_CONDITION_NOMATCH
+ *         if the header does not match, AP_CONDITION_WEAK if a weak match
+ *         was present and allowed by RFC2616, AP_CONDITION_STRONG for a
+ *         strong match.
+ */
+AP_DECLARE(ap_condition_e) ap_condition_if_none_match(request_rec *r,
+        apr_table_t *headers);
+
+/**
+ * Tests conditional request rules for the If-Modified-Since header.
+ * @param r The current request
+ * @param headers The response headers to check against
+ * @return AP_CONDITION_NONE if the header is missing, AP_CONDITION_NOMATCH
+ *         if the header does not match, AP_CONDITION_WEAK if a weak match
+ *         was present and allowed by RFC2616, AP_CONDITION_STRONG for a
+ *         strong match.
+ */
+AP_DECLARE(ap_condition_e) ap_condition_if_modified_since(request_rec *r,
+        apr_table_t *headers);
+
+/**
+ * Tests conditional request rules for the If-Range header.
+ * @param r The current request
+ * @param headers The response headers to check against
+ * @return AP_CONDITION_NONE if either the If-Range or Range header is
+ *         missing, AP_CONDITION_NOMATCH if the header does not match,
+ *         AP_CONDITION_STRONG for a strong match. Weak matches are not
+ *         permitted for the If-Range header.
+ */
+AP_DECLARE(ap_condition_e) ap_condition_if_range(request_rec *r,
+        apr_table_t *headers);
+
+/**
+ * Implements condition GET rules for HTTP/1.1 specification.  This function
+ * inspects the client headers and determines if the response fulfills
+ * the requirements specified.
+ * @param r The current request
+ * @return OK if the response fulfills the condition GET rules, some
+ *         other status code otherwise
+ */
+AP_DECLARE(int) ap_meets_conditions(request_rec *r);
+
+/* Other ways to send stuff at the client.  All of these keep track
+ * of bytes_sent automatically.  This indirection is intended to make
+ * it a little more painless to slide things like HTTP-NG packetization
+ * underneath the main body of the code later.  In the meantime, it lets
+ * us centralize a bit of accounting (bytes_sent).
+ *
+ * These also return the number of bytes written by the call.
+ * They should only be called with a timeout registered, for obvious reaasons.
+ * (Ditto the send_header stuff).
+ */
+
+/**
+ * Send an entire file to the client, using sendfile if supported by the
+ * current platform
+ * @param fd The file to send.
+ * @param r The current request
+ * @param offset Offset into the file to start sending.
+ * @param length Amount of data to send
+ * @param nbytes Amount of data actually sent
+ */
+AP_DECLARE(apr_status_t) ap_send_fd(apr_file_t *fd, request_rec *r, apr_off_t offset,
+                                   apr_size_t length, apr_size_t *nbytes);
+
+#if APR_HAS_MMAP
+/**
+ * Send an MMAP'ed file to the client
+ * @param mm The MMAP'ed file to send
+ * @param r The current request
+ * @param offset The offset into the MMAP to start sending
+ * @param length The amount of data to send
+ * @return The number of bytes sent
+ */
+AP_DECLARE(apr_size_t) ap_send_mmap(apr_mmap_t *mm,
+                                    request_rec *r,
+                                    apr_size_t offset,
+                                    apr_size_t length);
+#endif
+
+
+/**
+ * Register a new request method, and return the offset that will be
+ * associated with that method.
+ *
+ * @param p        The pool to create registered method numbers from.
+ * @param methname The name of the new method to register.
+ * @return         An int value representing an offset into a bitmask.
+ */
+AP_DECLARE(int) ap_method_register(apr_pool_t *p, const char *methname);
+
+/**
+ * Initialize the method_registry and allocate memory for it.
+ *
+ * @param p Pool to allocate memory for the registry from.
+ */
+AP_DECLARE(void) ap_method_registry_init(apr_pool_t *p);
+
+/**
+ * This is a convenience macro to ease with checking a mask
+ * against a method name.
+ */
+#define AP_METHOD_CHECK_ALLOWED(mask, methname) \
+    ((mask) & (AP_METHOD_BIT << ap_method_number_of((methname))))
+
+/**
+ * Create a new method list with the specified number of preallocated
+ * slots for extension methods.
+ *
+ * @param   p       Pointer to a pool in which the structure should be
+ *                  allocated.
+ * @param   nelts   Number of preallocated extension slots
+ * @return  Pointer to the newly created structure.
+ */
+AP_DECLARE(ap_method_list_t *) ap_make_method_list(apr_pool_t *p, int nelts);
+
+
+/**
+ * Copy a method list
+ *
+ * @param   dest List to copy to
+ * @param   src  List to copy from
+ */
+AP_DECLARE(void) ap_copy_method_list(ap_method_list_t *dest,
+                                     ap_method_list_t *src);
+
+/**
+ * Search for an HTTP method name in an ap_method_list_t structure, and
+ * return true if found.
+ *
+ * @param   method  String containing the name of the method to check.
+ * @param   l       Pointer to a method list, such as r->allowed_methods.
+ * @return  1 if method is in the list, otherwise 0
+ */
+AP_DECLARE(int) ap_method_in_list(ap_method_list_t *l, const char *method);
+
+/**
+ * Add an HTTP method name to an ap_method_list_t structure if it isn't
+ * already listed.
+ *
+ * @param   method  String containing the name of the method to check.
+ * @param   l       Pointer to a method list, such as r->allowed_methods.
+ * @return  None.
+ */
+AP_DECLARE(void) ap_method_list_add(ap_method_list_t *l, const char *method);
+
+/**
+ * Remove an HTTP method name from an ap_method_list_t structure.
+ *
+ * @param   l       Pointer to a method list, such as r->allowed_methods.
+ * @param   method  String containing the name of the method to remove.
+ * @return  None.
+ */
+AP_DECLARE(void) ap_method_list_remove(ap_method_list_t *l,
+                                       const char *method);
+
+/**
+ * Reset a method list to be completely empty.
+ *
+ * @param   l       Pointer to a method list, such as r->allowed_methods.
+ * @return  None.
+ */
+AP_DECLARE(void) ap_clear_method_list(ap_method_list_t *l);
+
+/**
+ * Set the content type for this request (r->content_type).
+ * @param r The current request
+ * @param ct The new content type
+ * @warning This function must be called to set r->content_type in order
+ * for the AddOutputFilterByType directive to work correctly.
+ */
+AP_DECLARE(void) ap_set_content_type(request_rec *r, const char *ct);
+
+/**
+ * Set the Accept-Ranges header for this response
+ * @param r The current request
+ */
+AP_DECLARE(void) ap_set_accept_ranges(request_rec *r);
+
+
+/* Hmmm... could macrofy these for now, and maybe forever, though the
+ * definitions of the macros would get a whole lot hairier.
+ */
+
+/**
+ * Output one character for this request
+ * @param c the character to output
+ * @param r the current request
+ * @return The number of bytes sent
+ */
+AP_DECLARE(int) ap_rputc(int c, request_rec *r);
+
+/**
+ * Write a buffer for the current request
+ * @param buf The buffer to write
+ * @param nbyte The number of bytes to send from the buffer
+ * @param r The current request
+ * @return The number of bytes sent
+ */
+AP_DECLARE(int) ap_rwrite(const void *buf, int nbyte, request_rec *r);
+
+/**
+ * Output a string for the current request
+ * @param str The string to output
+ * @param r The current request
+ * @return The number of bytes sent
+ * @note ap_rputs may be implemented as macro or inline function
+ */
+static APR_INLINE int ap_rputs(const char *str, request_rec *r)
+{
+    apr_size_t len;
+
+    len = strlen(str);
+
+    for (;;) {
+        if (len <= INT_MAX) {
+            return ap_rwrite(str, (int)len, r);
+        }
+        else {
+            int rc;
+
+            rc = ap_rwrite(str, INT_MAX, r);
+            if (rc < 0) {
+                return rc;
+            }
+            else {
+                str += INT_MAX;
+                len -= INT_MAX;
+            }
+        }
+    }
+}
+
+/**
+ * Write an unspecified number of strings to the request
+ * @param r The current request
+ * @param ... The strings to write
+ * @return The number of bytes sent
+ */
+AP_DECLARE_NONSTD(int) ap_rvputs(request_rec *r,...)
+                       AP_FN_ATTR_SENTINEL;
+
+/**
+ * Output data to the client in a printf format
+ * @param r The current request
+ * @param fmt The format string
+ * @param vlist The arguments to use to fill out the format string
+ * @return The number of bytes sent
+ */
+AP_DECLARE(int) ap_vrprintf(request_rec *r, const char *fmt, va_list vlist);
+
+/**
+ * Output data to the client in a printf format
+ * @param r The current request
+ * @param fmt The format string
+ * @param ... The arguments to use to fill out the format string
+ * @return The number of bytes sent
+ */
+AP_DECLARE_NONSTD(int) ap_rprintf(request_rec *r, const char *fmt,...)
+                                __attribute__((format(printf,2,3)));
+
+/**
+ * Flush all of the data for the current request to the client
+ * @param r The current request
+ * @return 0 on success, -1 if an error occurred
+ */
+AP_DECLARE(int) ap_rflush(request_rec *r);
+
+/**
+ * Index used in custom_responses array for a specific error code
+ * (only use outside protocol.c is in getting them configured).
+ * @param status HTTP status code
+ * @return The index of the response
+ */
+AP_DECLARE(int) ap_index_of_response(int status);
+
+/**
+ * Return the Status-Line for a given status code (excluding the
+ * HTTP-Version field). If an invalid or unknown status code is
+ * passed, "500 Internal Server Error" will be returned.
+ * @param status The HTTP status code
+ * @return The Status-Line
+ */
+AP_DECLARE(const char *) ap_get_status_line(int status);
+
+/**
+ * Return the Status-Line for a given status code (excluding the
+ * HTTP-Version field). If an invalid status code is passed,
+ * "500 Internal Server Error" will be returned, whereas an unknown
+ * status will be returned like "xxx Status xxx".
+ * @param p The pool to allocate from when status is unknown
+ * @param status The HTTP status code
+ * @return The Status-Line
+ */
+AP_DECLARE(const char *) ap_get_status_line_ex(apr_pool_t *p, int status);
+
+/* Reading a block of data from the client connection (e.g., POST arg) */
+
+/**
+ * Setup the client to allow Apache to read the request body.
+ * @param r The current request
+ * @param read_policy How the server should interpret a chunked
+ *                    transfer-encoding.  One of: <pre>
+ *    REQUEST_NO_BODY          Send 413 error if message has any body
+ *    REQUEST_CHUNKED_ERROR    Send 411 error if body without Content-Length
+ *    REQUEST_CHUNKED_DECHUNK  If chunked, remove the chunks for me.
+ * </pre>
+ * @return either OK or an error code
+ */
+AP_DECLARE(int) ap_setup_client_block(request_rec *r, int read_policy);
+
+/**
+ * Determine if the client has sent any data.  This also sends a
+ * 100 Continue response to HTTP/1.1 clients, so modules should not be called
+ * until the module is ready to read content.
+ * @warning Never call this function more than once.
+ * @param r The current request
+ * @return 0 if there is no message to read, 1 otherwise
+ */
+AP_DECLARE(int) ap_should_client_block(request_rec *r);
+
+/**
+ * Call this in a loop.  It will put data into a buffer and return the length
+ * of the input block
+ * @param r The current request
+ * @param buffer The buffer in which to store the data
+ * @param bufsiz The size of the buffer
+ * @return Number of bytes inserted into the buffer.  When done reading, 0
+ *         if EOF, or -1 if there was an error
+ */
+AP_DECLARE(long) ap_get_client_block(request_rec *r, char *buffer, apr_size_t bufsiz);
+
+/**
+ * Map specific APR codes returned by the filter stack to HTTP error
+ * codes, or the default status code provided. Use it as follows:
+ *
+ * return ap_map_http_request_error(rv, HTTP_BAD_REQUEST);
+ *
+ * If the filter has already handled the error, AP_FILTER_ERROR will
+ * be returned, which is cleanly passed through.
+ *
+ * These mappings imply that the filter stack is reading from the
+ * downstream client, the proxy will map these codes differently.
+ * @param rv APR status code
+ * @param status Default HTTP code should the APR code not be recognised
+ * @return Mapped HTTP status code
+ */
+AP_DECLARE(int) ap_map_http_request_error(apr_status_t rv, int status);
+
+/**
+ * In HTTP/1.1, any method can have a body.  However, most GET handlers
+ * wouldn't know what to do with a request body if they received one.
+ * This helper routine tests for and reads any message body in the request,
+ * simply discarding whatever it receives.  We need to do this because
+ * failing to read the request body would cause it to be interpreted
+ * as the next request on a persistent connection.
+ * @param r The current request
+ * @return error status if request is malformed, OK otherwise
+ */
+AP_DECLARE(int) ap_discard_request_body(request_rec *r);
+
+/**
+ * Setup the output headers so that the client knows how to authenticate
+ * itself the next time, if an authentication request failed.
+ * @param r The current request
+ */
+AP_DECLARE(void) ap_note_auth_failure(request_rec *r);
+
+/**
+ * @deprecated @see ap_note_auth_failure
+ */
+AP_DECLARE(void) ap_note_basic_auth_failure(request_rec *r);
+
+/**
+ * @deprecated @see ap_note_auth_failure
+ */
+AP_DECLARE(void) ap_note_digest_auth_failure(request_rec *r);
+
+/**
+ * This hook allows modules to add support for a specific auth type to
+ * ap_note_auth_failure
+ * @param r the current request
+ * @param auth_type the configured auth_type
+ * @return OK, DECLINED
+ */
+AP_DECLARE_HOOK(int, note_auth_failure, (request_rec *r, const char *auth_type))
+
+/**
+ * Get the password from the request headers. This function has multiple side
+ * effects due to its prior use in the old authentication framework.
+ * ap_get_basic_auth_components() should be preferred.
+ *
+ * @deprecated @see ap_get_basic_auth_components
+ * @param r The current request
+ * @param pw The password as set in the headers
+ * @return 0 (OK) if it set the 'pw' argument (and assured
+ *         a correct value in r->user); otherwise it returns
+ *         an error code, either HTTP_INTERNAL_SERVER_ERROR if things are
+ *         really confused, HTTP_UNAUTHORIZED if no authentication at all
+ *         seemed to be in use, or DECLINED if there was authentication but
+ *         it wasn't Basic (in which case, the caller should presumably
+ *         decline as well).
+ */
+AP_DECLARE(int) ap_get_basic_auth_pw(request_rec *r, const char **pw);
+
+#define AP_GET_BASIC_AUTH_PW_NOTE "AP_GET_BASIC_AUTH_PW_NOTE"
+
+/**
+ * Get the username and/or password from the request's Basic authentication
+ * headers. Unlike ap_get_basic_auth_pw(), calling this function has no side
+ * effects on the passed request_rec.
+ *
+ * @param r The current request
+ * @param username If not NULL, set to the username sent by the client
+ * @param password If not NULL, set to the password sent by the client
+ * @return APR_SUCCESS if the credentials were successfully parsed and returned;
+ *         APR_EINVAL if there was no authentication header sent or if the
+ *         client was not using the Basic authentication scheme. username and
+ *         password are unchanged on failure.
+ */
+AP_DECLARE(apr_status_t) ap_get_basic_auth_components(const request_rec *r,
+                                                      const char **username,
+                                                      const char **password);
+
+/**
+ * parse_uri: break apart the uri
+ * @warning Side Effects:
+ *    @li sets r->args to rest after '?' (or NULL if no '?')
+ *    @li sets r->uri to request uri (without r->args part)
+ *    @li sets r->hostname (if not set already) from request (scheme://host:port)
+ * @param r The current request
+ * @param uri The uri to break apart
+ */
+AP_CORE_DECLARE(void) ap_parse_uri(request_rec *r, const char *uri);
+
+#define AP_GETLINE_FOLD 1 /* Whether to merge continuation lines */
+#define AP_GETLINE_CRLF 2 /* Whether line ends must be in the form CR LF */
+#define AP_GETLINE_NOSPC_EOL 4 /* Whether to consume up to and including the
+                                  end of line on APR_ENOSPC */
+
+/**
+ * Get the next line of input for the request
+ * @param s The buffer into which to read the line
+ * @param n The size of the buffer
+ * @param r The request
+ * @param flags Bit flag of multiple parsing options
+ *              AP_GETLINE_FOLD Whether to merge continuation lines
+ *              AP_GETLINE_CRLF Whether line ends must be in the form CR LF
+ * @return The length of the line, if successful
+ *         n, if the line is too big to fit in the buffer
+ *         -1 for miscellaneous errors
+ */
+AP_DECLARE(int) ap_getline(char *s, int n, request_rec *r, int flags);
+
+/**
+ * Get the next line of input for the request
+ *
+ * Note: on ASCII boxes, ap_rgetline is a macro which simply calls
+ *       ap_rgetline_core to get the line of input.
+ *
+ *       on EBCDIC boxes, ap_rgetline is a wrapper function which
+ *       translates ASCII protocol lines to the local EBCDIC code page
+ *       after getting the line of input.
+ *
+ * @param s Pointer to the pointer to the buffer into which the line
+ *          should be read; if *s==NULL, a buffer of the necessary size
+ *          to hold the data will be allocated from the request pool
+ * @param n The size of the buffer
+ * @param read The length of the line.
+ * @param r The request
+ * @param flags Bit flag of multiple parsing options
+ *              AP_GETLINE_FOLD Whether to merge continuation lines
+ *              AP_GETLINE_CRLF Whether line ends must be in the form CR LF
+ * @param bb Working brigade to use when reading buckets
+ * @return APR_SUCCESS, if successful
+ *         APR_ENOSPC, if the line is too big to fit in the buffer
+ *         Other errors where appropriate
+ */
+#if APR_CHARSET_EBCDIC
+AP_DECLARE(apr_status_t) ap_rgetline(char **s, apr_size_t n,
+                                     apr_size_t *read,
+                                     request_rec *r, int flags,
+                                     apr_bucket_brigade *bb);
+#else /* ASCII box */
+#define ap_rgetline(s, n, read, r, fold, bb) \
+        ap_rgetline_core((s), (n), (read), (r), (fold), (bb))
+#endif
+
+/** @see ap_rgetline */
+AP_DECLARE(apr_status_t) ap_rgetline_core(char **s, apr_size_t n,
+                                          apr_size_t *read,
+                                          request_rec *r, int flags,
+                                          apr_bucket_brigade *bb);
+
+/**
+ * Get the method number associated with the given string, assumed to
+ * contain an HTTP method.  Returns M_INVALID if not recognized.
+ * @param method A string containing a valid HTTP method
+ * @return The method number
+ */
+AP_DECLARE(int) ap_method_number_of(const char *method);
+
+/**
+ * Get the method name associated with the given internal method
+ * number.  Returns NULL if not recognized.
+ * @param p A pool to use for temporary allocations.
+ * @param methnum An integer value corresponding to an internal method number
+ * @return The name corresponding to the method number
+ */
+AP_DECLARE(const char *) ap_method_name_of(apr_pool_t *p, int methnum);
+
+
+/* Hooks */
+/*
+ * pre_read_request --- run right before read_request_line(),
+ *                  and not run during any subrequests.
+ */
+/**
+ * This hook allows modules to affect the request or connection immediately before
+ * the request has been read, and before any other phases have been processes.
+ * @param r The current request of the soon-to-be-read request
+ * @param c The connection
+ * @return None/void
+ */
+AP_DECLARE_HOOK(void,pre_read_request,(request_rec *r, conn_rec *c))
+
+/*
+ * post_read_request --- run right after read_request or internal_redirect,
+ *                  and not run during any subrequests.
+ */
+/**
+ * This hook allows modules to affect the request immediately after the request
+ * has been read, and before any other phases have been processes.  This allows
+ * modules to make decisions based upon the input header fields
+ * @param r The current request
+ * @return OK or DECLINED
+ */
+AP_DECLARE_HOOK(int,post_read_request,(request_rec *r))
+
+/**
+ * This hook allows modules to perform any module-specific logging activities
+ * over and above the normal server things.
+ * @param r The current request
+ * @return OK, DECLINED, or HTTP_...
+ */
+AP_DECLARE_HOOK(int,log_transaction,(request_rec *r))
+
+/**
+ * This hook allows modules to retrieve the http scheme for a request.  This
+ * allows Apache modules to easily extend the schemes that Apache understands
+ * @param r The current request
+ * @return The http scheme from the request
+ */
+AP_DECLARE_HOOK(const char *,http_scheme,(const request_rec *r))
+
+/**
+ * Return the default port from the current request
+ * @param r The current request
+ * @return The current port
+ */
+AP_DECLARE_HOOK(apr_port_t,default_port,(const request_rec *r))
+
+
+#define AP_PROTOCOL_HTTP1        "http/1.1"
+
+/**
+ * Determine the list of protocols available for a connection/request. This may
+ * be collected with or without any request sent, in which case the request is 
+ * NULL. Or it may be triggered by the request received, e.g. through the 
+ * "Upgrade" header.
+ *
+ * This hook will be run whenever protocols are being negotiated (ALPN as
+ * one example). It may also be invoked at other times, e.g. when the server
+ * wants to advertise protocols it is capable of switching to.
+ * 
+ * The identifiers for protocols are taken from the TLS extension type ALPN:
+ * https://www.iana.org/assignments/tls-extensiontype-values/tls-extensiontype-values.xml
+ *
+ * If no protocols are added to the proposals, the server not perform any
+ * switch. If the protocol selected from the proposals is the protocol
+ * already in place, also no protocol switch will be invoked.
+ *
+ * The client may already have announced the protocols it is willing to
+ * accept. These will then be listed as offers. This parameter may also
+ * be NULL, indicating that offers from the client are not known and
+ * the hooks should propose all protocols that are valid for the
+ * current connection/request.
+ *
+ * All hooks are run, unless one returns an error. Proposals may contain
+ * duplicates. The order in which proposals are added is usually ignored.
+ * 
+ * @param c The current connection
+ * @param r The current request or NULL
+ * @param s The server/virtual host selected
+ * @param offers A list of protocol identifiers offered by the client or
+ *               NULL to indicated that the hooks are free to propose 
+ * @param proposals The list of protocol identifiers proposed by the hooks
+ * @return OK or DECLINED
+ * @bug This API or implementation and order of operations should be considered
+ * experimental and will continue to evolve in future 2.4 releases, with
+ * a corresponding minor module magic number (MMN) bump to indicate the
+ * API revision level.
+ */
+AP_DECLARE_HOOK(int,protocol_propose,(conn_rec *c, request_rec *r,
+                                      server_rec *s,
+                                      const apr_array_header_t *offers,
+                                      apr_array_header_t *proposals))
+
+/**
+ * Perform a protocol switch on the connection. The exact requirements for
+ * that depend on the protocol in place and the one switched to. The first 
+ * protocol module to handle the switch is the last module run.
+ * 
+ * For a connection level switch (r == NULL), the handler must on return
+ * leave the conn_rec in a state suitable for processing the switched
+ * protocol, e.g. correct filters in place.
+ *
+ * For a request triggered switch (r != NULL), the protocol switch is done
+ * before the response is sent out. When switching from "http/1.1" via Upgrade
+ * header, the 101 intermediate response will have been sent. The
+ * hook needs then to process the connection until it can be closed. Which
+ * the server will enforce on hook return.
+ * Any error the hook might encounter must already be sent by the hook itself
+ * to the client in whatever form the new protocol requires.
+ *
+ * @param c The current connection
+ * @param r The current request or NULL
+ * @param s The server/virtual host selected
+ * @param protocol The protocol identifier we try to switch to
+ * @return OK or DECLINED
+ * @bug This API or implementation and order of operations should be considered
+ * experimental and will continue to evolve in future 2.4 releases, with
+ * a corresponding minor module magic number (MMN) bump to indicate the
+ * API revision level.
+ */
+AP_DECLARE_HOOK(int,protocol_switch,(conn_rec *c, request_rec *r,
+                                     server_rec *s,
+                                     const char *protocol))
+
+/**
+ * Return the protocol used on the connection. Modules implementing
+ * protocol switching must register here and return the correct protocol
+ * identifier for connections they switched.
+ *
+ * To find out the protocol for the current connection, better call
+ * @see ap_get_protocol which internally uses this hook.
+ *
+ * @param c The current connection
+ * @return The identifier of the protocol in place or NULL
+ * @bug This API or implementation and order of operations should be considered
+ * experimental and will continue to evolve in future 2.4 releases, with
+ * a corresponding minor module magic number (MMN) bump to indicate the
+ * API revision level.
+ */
+AP_DECLARE_HOOK(const char *,protocol_get,(const conn_rec *c))
+
+/**
+ * Get the protocols that the connection and optional request may
+ * upgrade to - besides the protocol currently active on the connection. These
+ * values may be used to announce to a client what choices it has.
+ *
+ * If report_all == 0, only protocols more preferable than the one currently
+ * being used, are reported. Otherwise, all available protocols beside the
+ * current one are being reported.
+ *
+ * @param c The current connection
+ * @param r The current request or NULL
+ * @param s The server/virtual host selected or NULL
+ * @param report_all include also protocols less preferred than the current one
+ * @param pupgrades on return, possible protocols to upgrade to in descending order 
+ *                 of preference. Maybe NULL if none are available.    
+ * @bug This API or implementation and order of operations should be considered
+ * experimental and will continue to evolve in future 2.4 releases, with
+ * a corresponding minor module magic number (MMN) bump to indicate the
+ * API revision level.
+ */
+AP_DECLARE(apr_status_t) ap_get_protocol_upgrades(conn_rec *c, request_rec *r, 
+                                                  server_rec *s, int report_all, 
+                                                  const apr_array_header_t **pupgrades);
+                                                  
+/**
+ * Select a protocol for the given connection and optional request. Will return
+ * the protocol identifier selected which may be the protocol already in place
+ * on the connection. The selected protocol will be NULL if non of the given
+ * choices could be agreed upon (e.g. no proposal as made).
+ *
+ * A special case is where the choices itself is NULL (instead of empty). In
+ * this case there are no restrictions imposed on protocol selection.
+ *
+ * @param c The current connection
+ * @param r The current request or NULL
+ * @param s The server/virtual host selected
+ * @param choices A list of protocol identifiers, normally the clients whishes
+ * @return The selected protocol or NULL if no protocol could be agreed upon
+ * @bug This API or implementation and order of operations should be considered
+ * experimental and will continue to evolve in future 2.4 releases, with
+ * a corresponding minor module magic number (MMN) bump to indicate the
+ * API revision level.
+ */
+AP_DECLARE(const char *) ap_select_protocol(conn_rec *c, request_rec *r, 
+                                            server_rec *s,
+                                            const apr_array_header_t *choices);
+
+/**
+ * Perform the actual protocol switch. The protocol given must have been
+ * selected before on the very same connection and request pair.
+ *
+ * @param c The current connection
+ * @param r The current request or NULL
+ * @param s The server/virtual host selected
+ * @param protocol the protocol to switch to
+ * @return APR_SUCCESS, if caller may continue processing as usual
+ *         APR_EOF,     if caller needs to stop processing the connection
+ *         APR_EINVAL,  if the protocol is already in place
+ *         APR_NOTIMPL, if no module performed the switch
+ *         Other errors where appropriate
+ * @bug This API or implementation and order of operations should be considered
+ * experimental and will continue to evolve in future 2.4 releases, with
+ * a corresponding minor module magic number (MMN) bump to indicate the
+ * API revision level.
+ */
+AP_DECLARE(apr_status_t) ap_switch_protocol(conn_rec *c, request_rec *r, 
+                                            server_rec *s,
+                                            const char *protocol);
+
+/**
+ * Call the protocol_get hook to determine the protocol currently in use
+ * for the given connection.
+ *
+ * Unless another protocol has been switch to, will default to
+ * @see AP_PROTOCOL_HTTP1 and modules implementing a  new protocol must
+ * report a switched connection via the protocol_get hook.
+ *
+ * @param c The connection to determine the protocol for
+ * @return the protocol in use, never NULL
+ * @bug This API or implementation and order of operations should be considered
+ * experimental and will continue to evolve in future 2.4 releases, with
+ * a corresponding minor module magic number (MMN) bump to indicate the
+ * API revision level.
+ */
+AP_DECLARE(const char *) ap_get_protocol(conn_rec *c);
+
+/**
+ * Check if the given protocol is an allowed choice on the given
+ * combination of connection, request and server. 
+ *
+ * When server is NULL, it is taken from request_rec, unless
+ * request_rec is NULL. Then it is taken from the connection base
+ * server.
+ *
+ * @param c The current connection
+ * @param r The current request or NULL
+ * @param s The server/virtual host selected or NULL
+ * @param protocol the protocol to switch to
+ * @return != 0 iff protocol is allowed
+ * @bug This API or implementation and order of operations should be considered
+ * experimental and will continue to evolve in future 2.4 releases, with
+ * a corresponding minor module magic number (MMN) bump to indicate the
+ * API revision level.
+ */
+AP_DECLARE(int) ap_is_allowed_protocol(conn_rec *c, request_rec *r,
+                                       server_rec *s, const char *protocol);
+
+/** @see ap_bucket_type_error */
+typedef struct ap_bucket_error ap_bucket_error;
+
+/**
+ * @struct ap_bucket_error
+ * @brief  A bucket referring to an HTTP error
+ *
+ * This bucket can be passed down the filter stack to indicate that an
+ * HTTP error occurred while running a filter.  In order for this bucket
+ * to be used successfully, it MUST be sent as the first bucket in the
+ * first brigade to be sent from a given filter.
+ */
+struct ap_bucket_error {
+    /** Number of buckets using this memory */
+    apr_bucket_refcount refcount;
+    /** The error code */
+    int status;
+    /** The error string */
+    const char    *data;
+};
+
+/** @see ap_bucket_type_error */
+AP_DECLARE_DATA extern const apr_bucket_type_t ap_bucket_type_error;
+
+/**
+ * Determine if a bucket is an error bucket
+ * @param e The bucket to inspect
+ * @return true or false
+ */
+#define AP_BUCKET_IS_ERROR(e)         (e->type == &ap_bucket_type_error)
+
+/**
+ * Make the bucket passed in an error bucket
+ * @param b The bucket to make into an error bucket
+ * @param error The HTTP error code to put in the bucket.
+ * @param buf An optional error string to put in the bucket.
+ * @param p A pool to allocate out of.
+ * @return The new bucket, or NULL if allocation failed
+ */
+AP_DECLARE(apr_bucket *) ap_bucket_error_make(apr_bucket *b, int error,
+                const char *buf, apr_pool_t *p);
+
+/**
+ * Create a bucket referring to an HTTP error.
+ * @param error The HTTP error code to put in the bucket.
+ * @param buf An optional error string to put in the bucket.
+ * @param p A pool to allocate the error string out of.
+ * @param list The bucket allocator from which to allocate the bucket
+ * @return The new bucket, or NULL if allocation failed
+ */
+AP_DECLARE(apr_bucket *) ap_bucket_error_create(int error, const char *buf,
+                                                apr_pool_t *p,
+                                                apr_bucket_alloc_t *list);
+
+AP_DECLARE_NONSTD(apr_status_t) ap_byterange_filter(ap_filter_t *f, apr_bucket_brigade *b);
+AP_DECLARE_NONSTD(apr_status_t) ap_http_header_filter(ap_filter_t *f, apr_bucket_brigade *b);
+AP_DECLARE_NONSTD(apr_status_t) ap_content_length_filter(ap_filter_t *,
+                                                              apr_bucket_brigade *);
+AP_DECLARE_NONSTD(apr_status_t) ap_old_write_filter(ap_filter_t *f, apr_bucket_brigade *b);
+
+/**
+ * Sett up the protocol fields for subsidiary requests
+ * @param rnew New Sub Request
+ * @param r current request
+ */
+AP_DECLARE(void) ap_set_sub_req_protocol(request_rec *rnew, const request_rec *r);
+
+/**
+ * A wrapup function to keep the internal accounting straight.
+ * Indicates that there is no more content coming.
+ * @param sub_r Subrequest that is now compete
+ */
+AP_DECLARE(void) ap_finalize_sub_req_protocol(request_rec *sub_r);
+
+/**
+ * Send an interim (HTTP 1xx) response immediately.
+ * @param r The request
+ * @param send_headers Whether to send&clear headers in r->headers_out
+ */
+AP_DECLARE(void) ap_send_interim_response(request_rec *r, int send_headers);
+
+
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif  /* !APACHE_HTTP_PROTOCOL_H */
+/** @} */