mod_rewrite.h

Apache HTTP Server 是一个功能强大的灵活的与HTTP/1.1相兼容的web服务器.这里给出的是Apache HTTP服务器的源码。

/* Copyright 1999-2005 The Apache Software Foundation or its licensors, as
 * applicable.
 *
 * Licensed 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 MOD_REWRITE_H
#define MOD_REWRITE_H 1

/*
**                       _                            _ _
**   _ __ ___   ___   __| |    _ __ _____      ___ __(_) |_ ___
**  | '_ ` _ \ / _ \ / _` |   | '__/ _ \ \ /\ / / '__| | __/ _ \
**  | | | | | | (_) | (_| |   | | |  __/\ V  V /| |  | | ||  __/
**  |_| |_| |_|\___/ \__,_|___|_|  \___| \_/\_/ |_|  |_|\__\___|
**                       |_____|
**
**  URL Rewriting Module
**
**  This module uses a rule-based rewriting engine (based on a
**  regular-expression parser) to rewrite requested URLs on the fly.
**
**  It supports an unlimited number of additional rule conditions (which can
**  operate on a lot of variables, even on HTTP headers) for granular
**  matching and even external database lookups (either via plain text
**  tables, DBM hash files or even external processes) for advanced URL
**  substitution.
**
**  It operates on the full URLs (including the PATH_INFO part) both in
**  per-server context (httpd.conf) and per-dir context (.htaccess) and even
**  can generate QUERY_STRING parts on result.   The rewriting result finally
**  can lead to internal subprocessing, external request redirection or even
**  to internal proxy throughput.
**
**  This module was originally written in April 1996 and
**  gifted exclusively to the The Apache Software Foundation in July 1997 by
**
**      Ralf S. Engelschall
**      [e-mail]
**      www.engelschall.com
*/

#include "apr.h"

#define APR_WANT_STRFUNC
#define APR_WANT_MEMFUNC
#include "apr_want.h"

    /* Include from the underlaying Unix system ... */
#if APR_HAVE_STDARG_H
#include <stdarg.h>
#endif
#if APR_HAVE_STDLIB_H
#include <stdlib.h>
#endif
#if APR_HAVE_CTYPE_H
#include <ctype.h>
#endif
#if APR_HAVE_SYS_TYPES_H
#include <sys/types.h>
#endif

#if APR_HAS_THREADS
#include "apr_thread_mutex.h"
#endif
#include "apr_optional.h"
#include "apr_dbm.h"
#include "ap_config.h"

    /* Include from the Apache server ... */
#define CORE_PRIVATE
#include "httpd.h"
#include "http_config.h"
#include "http_request.h"
#include "http_core.h"
#include "http_log.h"
#include "http_vhost.h"

    /*
     * The key in the r->notes apr_table_t wherein we store our accumulated
     * Vary values, and the one used for per-condition checks in a chain.
     */
#define VARY_KEY "rewrite-Vary"
#define VARY_KEY_THIS "rewrite-Vary-this"

/*
**
**  Some defines
**
*/

#define ENVVAR_SCRIPT_URL "SCRIPT_URL"
#define ENVVAR_SCRIPT_URI "SCRIPT_URI"

#define REWRITE_FORCED_MIMETYPE_NOTEVAR "rewrite-forced-mimetype"

#define CONDFLAG_NONE               1<<0
#define CONDFLAG_NOCASE             1<<1
#define CONDFLAG_NOTMATCH           1<<2
#define CONDFLAG_ORNEXT             1<<3

#define RULEFLAG_NONE               1<<0
#define RULEFLAG_FORCEREDIRECT      1<<1
#define RULEFLAG_LASTRULE           1<<2
#define RULEFLAG_NEWROUND           1<<3
#define RULEFLAG_CHAIN              1<<4
#define RULEFLAG_IGNOREONSUBREQ     1<<5
#define RULEFLAG_NOTMATCH           1<<6
#define RULEFLAG_PROXY              1<<7
#define RULEFLAG_PASSTHROUGH        1<<8
#define RULEFLAG_FORBIDDEN          1<<9
#define RULEFLAG_GONE               1<<10
#define RULEFLAG_QSAPPEND           1<<11
#define RULEFLAG_NOCASE             1<<12
#define RULEFLAG_NOESCAPE           1<<13

#define ACTION_NORMAL               1<<0
#define ACTION_NOESCAPE             1<<1

#define MAPTYPE_TXT                 1<<0
#define MAPTYPE_DBM                 1<<1
#define MAPTYPE_PRG                 1<<2
#define MAPTYPE_INT                 1<<3
#define MAPTYPE_RND                 1<<4

#define ENGINE_DISABLED             1<<0
#define ENGINE_ENABLED              1<<1

#define OPTION_NONE                 1<<0
#define OPTION_INHERIT              1<<1

#define CACHEMODE_TS                1<<0
#define CACHEMODE_TTL               1<<1

#define CACHE_TLB_ROWS 1024
#define CACHE_TLB_COLS 4

#ifndef FALSE
#define FALSE 0
#define TRUE  !FALSE
#endif

#ifndef NO
#define NO    FALSE
#define YES   TRUE
#endif

#ifndef RAND_MAX
#define RAND_MAX 32767
#endif

#ifndef LONG_STRING_LEN
#define LONG_STRING_LEN 2048
#endif

#define MAX_ENV_FLAGS 15
#define MAX_COOKIE_FLAGS 15
/*** max cookie size in rfc 2109 ***/
#define MAX_COOKIE_LEN 4096

/* default maximum number of internal redirects */
#define REWRITE_REDIRECT_LIMIT 10


/*
**
**  our private data structures we handle with
**
*/

    /* the list structures for holding the mapfile information
     * and the rewrite rules
     */
typedef struct {
    const char *name;              /* the name of the map */
    const char *datafile;          /* filename for map data files */
    const char *dbmtype;           /* dbm type for dbm map data files */
    const char *checkfile;         /* filename to check for map existence */
    int   type;                    /* the type of the map */
    apr_file_t *fpin;              /* in  file pointer for program maps */
    apr_file_t *fpout;             /* out file pointer for program maps */
    apr_file_t *fperr;             /* err file pointer for program maps */
    char *(*func)(request_rec *,   /* function pointer for internal maps */
                  char *);
    char **argv;
    char *cachename;               /* name for the cache */
} rewritemap_entry;

typedef struct {
    char    *input;                /* Input string of RewriteCond */
    char    *pattern;              /* the RegExp pattern string */
    regex_t *regexp;
    int      flags;                /* Flags which control the match */
} rewritecond_entry;

typedef struct {
    apr_array_header_t *rewriteconds;    /* the corresponding RewriteCond entries */
    char    *pattern;              /* the RegExp pattern string */
    regex_t *regexp;               /* the RegExp pattern compilation */
    char    *output;               /* the Substitution string */
    int      flags;                /* Flags which control the substitution */
    char    *forced_mimetype;      /* forced MIME type of substitution */
    int      forced_responsecode;  /* forced HTTP redirect response status */
    char    *env[MAX_ENV_FLAGS+1]; /* added environment variables */
    char    *cookie[MAX_COOKIE_FLAGS+1]; /* added cookies */
    int      skip;                 /* number of next rules to skip */
} rewriterule_entry;


    /* the per-server or per-virtual-server configuration
     * statically generated once on startup for every server
     */
typedef struct {
    int           state;           /* the RewriteEngine state */