src/http/ngx_http_request.h

/*
 * Copyright (C) Igor Sysoev
 */


#ifndef _NGX_HTTP_REQUEST_H_INCLUDED_
#define _NGX_HTTP_REQUEST_H_INCLUDED_


#define NGX_HTTP_MAX_URI_CHANGES           10
#define NGX_HTTP_MAX_SUBREQUESTS           50

/* must be 2^n */
#define NGX_HTTP_LC_HEADER_LEN             32


#define NGX_HTTP_DISCARD_BUFFER_SIZE       4096
#define NGX_HTTP_LINGERING_BUFFER_SIZE     4096


#define NGX_HTTP_VERSION_9                 9
#define NGX_HTTP_VERSION_10                1000
#define NGX_HTTP_VERSION_11                1001

#define NGX_HTTP_UNKNOWN                   0x0001
#define NGX_HTTP_GET                       0x0002
#define NGX_HTTP_HEAD                      0x0004
#define NGX_HTTP_POST                      0x0008
#define NGX_HTTP_PUT                       0x0010
#define NGX_HTTP_DELETE                    0x0020
#define NGX_HTTP_MKCOL                     0x0040
#define NGX_HTTP_COPY                      0x0080
#define NGX_HTTP_MOVE                      0x0100
#define NGX_HTTP_OPTIONS                   0x0200
#define NGX_HTTP_PROPFIND                  0x0400
#define NGX_HTTP_PROPPATCH                 0x0800
#define NGX_HTTP_LOCK                      0x1000
#define NGX_HTTP_UNLOCK                    0x2000
#define NGX_HTTP_TRACE                     0x4000

#define NGX_HTTP_CONNECTION_CLOSE          1
#define NGX_HTTP_CONNECTION_KEEP_ALIVE     2


#define NGX_NONE                           1


#define NGX_HTTP_PARSE_HEADER_DONE         1

#define NGX_HTTP_CLIENT_ERROR              10
#define NGX_HTTP_PARSE_INVALID_METHOD      10
#define NGX_HTTP_PARSE_INVALID_REQUEST     11
#define NGX_HTTP_PARSE_INVALID_09_METHOD   12

#define NGX_HTTP_PARSE_INVALID_HEADER      13


#define NGX_HTTP_ZERO_IN_URI               1
#define NGX_HTTP_SUBREQUEST_IN_MEMORY      2


#define NGX_HTTP_OK                        200
#define NGX_HTTP_CREATED                   201
#define NGX_HTTP_NO_CONTENT                204
#define NGX_HTTP_PARTIAL_CONTENT           206

#define NGX_HTTP_SPECIAL_RESPONSE          300
#define NGX_HTTP_MOVED_PERMANENTLY         301
#define NGX_HTTP_MOVED_TEMPORARILY         302
#define NGX_HTTP_NOT_MODIFIED              304

#define NGX_HTTP_BAD_REQUEST               400
#define NGX_HTTP_UNAUTHORIZED              401
#define NGX_HTTP_FORBIDDEN                 403
#define NGX_HTTP_NOT_FOUND                 404
#define NGX_HTTP_NOT_ALLOWED               405
#define NGX_HTTP_REQUEST_TIME_OUT          408
#define NGX_HTTP_CONFLICT                  409
#define NGX_HTTP_LENGTH_REQUIRED           411
#define NGX_HTTP_PRECONDITION_FAILED       412
#define NGX_HTTP_REQUEST_ENTITY_TOO_LARGE  413
#define NGX_HTTP_REQUEST_URI_TOO_LARGE     414
#define NGX_HTTP_UNSUPPORTED_MEDIA_TYPE    415
#define NGX_HTTP_RANGE_NOT_SATISFIABLE     416


/* Our own HTTP codes */

/* The special code to close connection without any response */
#define NGX_HTTP_CLOSE                     444

#define NGX_HTTP_OWN_CODES                 495

#define NGX_HTTPS_CERT_ERROR               495
#define NGX_HTTPS_NO_CERT                  496

/*
 * We use the special code for the plain HTTP requests that are sent to
 * HTTPS port to distinguish it from 4XX in an error page redirection
 */
#define NGX_HTTP_TO_HTTPS                  497

/* 498 is the canceled code for the requests with invalid host name */

/*
 * HTTP does not define the code for the case when a client closed
 * the connection while we are processing its request so we introduce
 * own code to log such situation when a client has closed the connection
 * before we even try to send the HTTP header to it
 */
#define NGX_HTTP_CLIENT_CLOSED_REQUEST     499


#define NGX_HTTP_INTERNAL_SERVER_ERROR     500
#define NGX_HTTP_NOT_IMPLEMENTED           501
#define NGX_HTTP_BAD_GATEWAY               502
#define NGX_HTTP_SERVICE_UNAVAILABLE       503
#define NGX_HTTP_GATEWAY_TIME_OUT          504
#define NGX_HTTP_INSUFFICIENT_STORAGE      507


#define NGX_HTTP_LOWLEVEL_BUFFERED         0xf0
#define NGX_HTTP_WRITE_BUFFERED            0x10
#define NGX_HTTP_GZIP_BUFFERED             0x20
#define NGX_HTTP_SSI_BUFFERED              0x01
#define NGX_HTTP_SUB_BUFFERED              0x02
#define NGX_HTTP_COPY_BUFFERED             0x04


typedef enum {
    NGX_HTTP_INITING_REQUEST_STATE = 0,
    NGX_HTTP_READING_REQUEST_STATE,
    NGX_HTTP_PROCESS_REQUEST_STATE,

    NGX_HTTP_CONNECT_UPSTREAM_STATE,
    NGX_HTTP_WRITING_UPSTREAM_STATE,
    NGX_HTTP_READING_UPSTREAM_STATE,

    NGX_HTTP_WRITING_REQUEST_STATE,
    NGX_HTTP_LINGERING_CLOSE_STATE,
    NGX_HTTP_KEEPALIVE_STATE
} ngx_http_state_e;


typedef struct {
    ngx_str_t                         name;
    ngx_uint_t                        offset;
    ngx_http_header_handler_pt        handler;
} ngx_http_header_t;


typedef struct {
    ngx_str_t                         name;
    ngx_uint_t                        offset;
} ngx_http_header_out_t;


typedef struct {
    ngx_list_t                        headers;

    ngx_table_elt_t                  *host;
    ngx_table_elt_t                  *connection;
    ngx_table_elt_t                  *if_modified_since;
    ngx_table_elt_t                  *user_agent;
    ngx_table_elt_t                  *referer;
    ngx_table_elt_t                  *content_length;
    ngx_table_elt_t                  *content_type;

    ngx_table_elt_t                  *range;
    ngx_table_elt_t                  *if_range;

    ngx_table_elt_t                  *transfer_encoding;

#if (NGX_HTTP_GZIP)
    ngx_table_elt_t                  *accept_encoding;
    ngx_table_elt_t                  *via;
#endif

    ngx_table_elt_t                  *authorization;

    ngx_table_elt_t                  *keep_alive;

#if (NGX_HTTP_PROXY || NGX_HTTP_REALIP)
    ngx_table_elt_t                  *x_forwarded_for;
#endif

#if (NGX_HTTP_REALIP)
    ngx_table_elt_t                  *x_real_ip;
#endif

#if (NGX_HTTP_HEADERS)
    ngx_table_elt_t                  *accept;
    ngx_table_elt_t                  *accept_language;
#endif

#if (NGX_HTTP_DAV)
    ngx_table_elt_t                  *depth;
    ngx_table_elt_t                  *destination;
    ngx_table_elt_t                  *overwrite;
    ngx_table_elt_t                  *date;
#endif

    ngx_str_t                         user;
    ngx_str_t                         passwd;

    ngx_array_t                       cookies;

    size_t                            host_name_len;
    off_t                             content_length_n;
    time_t                            keep_alive_n;

    unsigned                          connection_type:2;
    unsigned                          msie:1;
    unsigned                          msie4:1;
    unsigned                          opera:1;
    unsigned                          gecko:1;
    unsigned                          konqueror:1;
} ngx_http_headers_in_t;


typedef struct {
    ngx_list_t                        headers;

    ngx_uint_t                        status;
    ngx_str_t                         status_line;

    ngx_table_elt_t                  *server;
    ngx_table_elt_t                  *date;
    ngx_table_elt_t                  *content_length;
    ngx_table_elt_t                  *content_encoding;
    ngx_table_elt_t                  *location;
    ngx_table_elt_t                  *refresh;
    ngx_table_elt_t                  *last_modified;
    ngx_table_elt_t                  *content_range;
    ngx_table_elt_t                  *accept_ranges;
    ngx_table_elt_t                  *www_authenticate;
    ngx_table_elt_t                  *expires;
    ngx_table_elt_t                  *etag;

    ngx_str_t                        *override_charset;

    size_t                            content_type_len;
    ngx_str_t                         content_type;
    ngx_str_t                         charset;

    ngx_array_t                       cache_control;

    off_t                             content_length_n;
    time_t                            date_time;
    time_t                            last_modified_time;
} ngx_http_headers_out_t;


typedef void (*ngx_http_client_body_handler_pt)(ngx_http_request_t *r);

typedef struct {
    ngx_temp_file_t                  *temp_file;
    ngx_chain_t                      *bufs;
    ngx_buf_t                        *buf;
    off_t                             rest;
    ngx_chain_t                      *to_write;
    ngx_http_client_body_handler_pt   post_handler;
} ngx_http_request_body_t;


typedef struct {
    ngx_http_request_t               *request;

    ngx_buf_t                       **busy;
    ngx_int_t                         nbusy;

    ngx_buf_t                       **free;
    ngx_int_t                         nfree;

    ngx_uint_t                        pipeline;    /* unsigned  pipeline:1; */
} ngx_http_connection_t;


typedef struct ngx_http_server_name_s  ngx_http_server_name_t;


typedef struct {
     ngx_hash_combined_t              names;

     ngx_uint_t                       nregex;
     ngx_http_server_name_t          *regex;
} ngx_http_virtual_names_t;


typedef void (*ngx_http_cleanup_pt)(void *data);

typedef struct ngx_http_cleanup_s  ngx_http_cleanup_t;

struct ngx_http_cleanup_s {
    ngx_http_cleanup_pt               handler;
    void                             *data;
    ngx_http_cleanup_t               *next;
};


typedef ngx_int_t (*ngx_http_post_subrequest_pt)(ngx_http_request_t *r,
    void *data, ngx_int_t rc);

typedef struct {
    ngx_http_post_subrequest_pt       handler;
    void                             *data;
} ngx_http_post_subrequest_t;


typedef struct ngx_http_postponed_request_s  ngx_http_postponed_request_t;

struct ngx_http_postponed_request_s {
    ngx_http_request_t               *request;
    ngx_chain_t                      *out;
    ngx_http_postponed_request_t     *next;
};


typedef ngx_int_t (*ngx_http_handler_pt)(ngx_http_request_t *r);
typedef void (*ngx_http_event_handler_pt)(ngx_http_request_t *r);


struct ngx_http_request_s {
    uint32_t                          signature;         /* "HTTP" */

    ngx_connection_t                 *connection;

    void                            **ctx;
    void                            **main_conf;
    void                            **srv_conf;
    void                            **loc_conf;

    ngx_http_event_handler_pt         read_event_handler;
    ngx_http_event_handler_pt         write_event_handler;

    ngx_http_cache_t                 *cache;

    ngx_http_upstream_t              *upstream;
    ngx_array_t                      *upstream_states;
                                         /* of ngx_http_upstream_state_t */

    ngx_pool_t                       *pool;
    ngx_buf_t                        *header_in;

    ngx_http_headers_in_t             headers_in;
    ngx_http_headers_out_t            headers_out;

    ngx_http_request_body_t          *request_body;

    time_t                            lingering_time;
    time_t                            start_sec;
    ngx_msec_t                        start_msec;

    ngx_uint_t                        method;
    ngx_uint_t                        http_version;

    ngx_str_t                         request_line;
    ngx_str_t                         uri;
    ngx_str_t                         args;
    ngx_str_t                         exten;
    ngx_str_t                         unparsed_uri;

    ngx_str_t                         method_name;
    ngx_str_t                         http_protocol;

    ngx_chain_t                      *out;
    ngx_http_request_t               *main;
    ngx_http_request_t               *parent;
    ngx_http_postponed_request_t     *postponed;
    ngx_http_post_subrequest_t       *post_subrequest;

    uint32_t                          in_addr;
    ngx_uint_t                        port;
    ngx_str_t                        *port_text;    /* ":80" */
    ngx_http_virtual_names_t         *virtual_names;

    ngx_int_t                         phase_handler;
    ngx_http_handler_pt               content_handler;
    ngx_uint_t                        access_code;

    ngx_http_variable_value_t        *variables;

    size_t                            limit_rate;

    /* used to learn the Apache compatible response length without a header */
    size_t                            header_size;

    off_t                             request_length;

    ngx_uint_t                        err_status;

    ngx_http_connection_t            *http_connection;

    ngx_http_log_handler_pt           log_handler;

    ngx_http_cleanup_t               *cleanup;

    unsigned                          http_state:4;

    /* URI with "/." and on Win32 with "//" */
    unsigned                          complex_uri:1;

    /* URI with "%" */
    unsigned                          quoted_uri:1;

    /* URI with "+" */
    unsigned                          plus_in_uri:1;

    /* URI with "\0" or "%00" */
    unsigned                          zero_in_uri:1;

    unsigned                          invalid_header:1;

    unsigned                          valid_location:1;
    unsigned                          valid_unparsed_uri:1;
    unsigned                          uri_changed:1;
    unsigned                          uri_changes:4;

    unsigned                          request_body_in_single_buf:1;
    unsigned                          request_body_in_file_only:1;
    unsigned                          request_body_in_persistent_file:1;
    unsigned                          request_body_in_clean_file:1;
    unsigned                          request_body_file_group_access:1;
    unsigned                          request_body_file_log_level:3;

    unsigned                          fast_subrequest:1;
    unsigned                          subrequest_in_memory:1;

    unsigned                          gzip:2;

    unsigned                          proxy:1;
    unsigned                          bypass_cache:1;
    unsigned                          no_cache:1;

#if (NGX_HTTP_REALIP)

    /*
     * instead of using the request context data in ngx_http_realip_module
     * we use the single bit in the request structure
     */
    unsigned                          realip_set:1;

#endif

    /*
     * instead of using the request context data in ngx_http_limit_zone_module
     * we use the single bit in the request structure
     */
    unsigned                          limit_zone_set:1;

#if 0
    unsigned                          cacheable:1;
#endif

    unsigned                          pipeline:1;
    unsigned                          plain_http:1;
    unsigned                          chunked:1;
    unsigned                          header_only:1;
    unsigned                          zero_body:1;
    unsigned                          keepalive:1;
    unsigned                          lingering_close:1;
    unsigned                          discard_body:1;
    unsigned                          internal:1;
    unsigned                          error_page:1;
    unsigned                          post_action:1;
    unsigned                          request_complete:1;
    unsigned                          request_output:1;
    unsigned                          header_sent:1;
    unsigned                          done:1;
    unsigned                          utf8:1;

    unsigned                          buffered:4;

    unsigned                          main_filter_need_in_memory:1;
    unsigned                          filter_need_in_memory:1;
    unsigned                          filter_need_temporary:1;
    unsigned                          allow_ranges:1;

#if (NGX_STAT_STUB)
    unsigned                          stat_reading:1;
    unsigned                          stat_writing:1;
#endif

    unsigned                          subrequests:8;

    /* used to parse HTTP headers */

    ngx_uint_t                        state;
    u_char                           *uri_start;
    u_char                           *uri_end;
    u_char                           *uri_ext;
    u_char                           *args_start;
    u_char                           *request_start;
    u_char                           *request_end;
    u_char                           *method_end;
    u_char                           *schema_start;
    u_char                           *schema_end;
    u_char                           *host_start;
    u_char                           *host_end;
    u_char                           *port_start;
    u_char                           *port_end;
    u_char                           *header_name_start;
    u_char                           *header_name_end;
    u_char                           *header_start;
    u_char                           *header_end;

    unsigned                          http_minor:16;
    unsigned                          http_major:16;

    ngx_uint_t                        header_hash;
    ngx_uint_t                        lowcase_index;
    u_char                            lowcase_header[NGX_HTTP_LC_HEADER_LEN];
};


extern ngx_http_header_t       ngx_http_headers_in[];
extern ngx_http_header_out_t   ngx_http_headers_out[];


#endif /* _NGX_HTTP_REQUEST_H_INCLUDED_ */