From: (no author) <(no author)@unknown> Date: Mon, 9 Dec 1996 06:06:41 +0000 (+0000) Subject: This commit was manufactured by cvs2svn to create tag 'APACHE_1_2b2'. X-Git-Tag: APACHE_1_2b2^0 X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=54bfee287e17a47cd3f31db8c7a4eb46d078ae2e;p=thirdparty%2Fapache%2Fhttpd.git This commit was manufactured by cvs2svn to create tag 'APACHE_1_2b2'. git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/tags/APACHE_1_2b2@77239 13f79535-47bb-0310-9956-ffa450edef68 --- diff --git a/docs/docroot/apache_pb.gif b/docs/docroot/apache_pb.gif deleted file mode 100644 index 3a1c139fc42..00000000000 Binary files a/docs/docroot/apache_pb.gif and /dev/null differ diff --git a/docs/manual/bind.html.en b/docs/manual/bind.html.en deleted file mode 100644 index cb1fa0daacf..00000000000 --- a/docs/manual/bind.html.en +++ /dev/null @@ -1,100 +0,0 @@ - -Setting which addresses and ports Apache uses - - - -

Setting which addresses and ports Apache uses

- -
- -When Apache starts, it connects to some port and address on the -local machine and waits for incoming requests. By default, it -listens to all addresses on the machine, and to the port -as specified by the Port directive in the server configuration. -However, it can be told to listen to more the one port, or to listen -to only selected addresses, or a combination. This is often combined -with the Virtual Host feature which determines how Apache -responds to different IP addresses, hostnames and ports.

- -There are two directives used to restrict or specify which addresses -and ports Apache listens to. - -

- -

BindAddress

-Syntax: BindAddress [ * | IP-address | hostname ]
-Default: BindAddress *
-Context: server config
-Status: Core

- -Makes the server listen to just the specified address. If the argument -is *, the server listens to all addresses. The port listened to -is set with the Port directive. Only one BindAddress -should be used. - -

Listen

-Syntax: Listen [ port | IP-address:port ]
-Default: none
-Context: server config
-Status: Core

- -Listen can be used instead of BindAddress and -Port. It tells the server to accept incoming requests on the -specified port or address-and-port combination. If the first format is -used, with a port number only, the server listens to the given port on -all interfaces, instead of the port given by the Port -directive. If an IP address is given as well as a port, the server -will listen on the given port and interface.

Multiple Listen -directives may be used to specify a number of addresses and ports to -listen to. The server will respond to requests from any of the listed -addresses and ports.

- -For example, to make the server accept connections on both port -80 and port 8000, use: -

-   Listen 80
-   Listen 8000
-
- -To make the server accept connections on two specified -interfaces and port numbers, use -
-   Listen 192.170.2.1:80
-   Listen 192.170.2.5:8000
-
- -

How this works with Virtual Hosts

- -BindAddress and Listen do not implement Virtual Hosts. They tell the -main server what addresses and ports to listen to. If no -<VirtualHost> directives are used, the server will behave the -same for all accepted requests. However, <VirtualHost> can be -used to specify a different behavour for one or more of the addresses -and ports. To implement a VirtualHost, the server must first be told -to listen to the address and port to be used. Then a -<VirtualHost> section should be created for a specified address -and port to set the behavior of this virtual host. Note that if the -<VirtualHost> is set for an address and port that the server is -not listening to, it cannot be accessed. - -

See also

- -See also the documentation on -Virtual Hosts, -Non-IP virtual hosts, -BindAddress directive, -Port directive -and -<VirtualHost> section. - - - - - - diff --git a/docs/manual/content-negotiation.html.en b/docs/manual/content-negotiation.html.en deleted file mode 100644 index 6c589a9efb5..00000000000 --- a/docs/manual/content-negotiation.html.en +++ /dev/null @@ -1,213 +0,0 @@ - - -Apache server Content arbitration: MultiViews and *.var files - - - - -

Content Arbitration: MultiViews and *.var files

- -The HTTP standard allows clients (i.e., browsers like Mosaic or -Netscape) to specify what data formats they are prepared to accept. -The intention is that when information is available in multiple -variants (e.g., in different data formats), servers can use this -information to decide which variant to send. This feature has been -supported in the CERN server for a while, and while it is not yet -supported in the NCSA server, it is likely to assume a new importance -in light of the emergence of HTML3 capable browsers.

- -The Apache module mod_negotiation handles -content negotiation in two different ways; special treatment for the -pseudo-mime-type application/x-type-map, and the -MultiViews per-directory Option (which can be set in srm.conf, or in -.htaccess files, as usual). These features are alternate user -interfaces to what amounts to the same piece of code (in the new file -http_mime_db.c) which implements the content negotiation -portion of the HTTP protocol.

- -Each of these features allows one of several files to satisfy a -request, based on what the client says it's willing to accept; the -differences are in the way the files are identified: - -

- -Apache also supports a new pseudo-MIME type, -text/x-server-parsed-html3, which is treated as text/html;level=3 -for purposes of content negotiation, and as server-side-included HTML -elsewhere. - -

Type maps (*.var files)

- -A type map is a document which is typed by the server (using its -normal suffix-based mechanisms) as -application/x-type-map. Note that to use this feature, -you've got to have an AddType some place which defines a -file suffix as application/x-type-map; the easiest thing -may be to stick a -
-
-  AddType application/x-type-map var
-
-
-in srm.conf. See comments in the sample config files for -details.

- -Type map files have an entry for each available variant; these entries -consist of contiguous RFC822-format header lines. Entries for -different variants are separated by blank lines. Blank lines are -illegal within an entry. It is conventional to begin a map file with -an entry for the combined entity as a whole, e.g., -

-
-  URI: foo; vary="type,language"
-
-  URI: foo.en.html
-  Content-type: text/html; level=2
-  Content-language: en
-
-  URI: foo.fr.html
-  Content-type: text/html; level=2
-  Content-language: fr
-
-
-If the variants have different qualities, that may be indicated by the -"qs" parameter, as in this picture (available as jpeg, gif, or ASCII-art): -
-
-  URI: foo; vary="type,language"
-
-  URI: foo.jpeg
-  Content-type: image/jpeg; qs=0.8
-
-  URI: foo.gif
-  Content-type: image/gif; qs=0.5
-
-  URI: foo.txt
-  Content-type: text/plain; qs=0.01
-
-

- -The full list of headers recognized is: - -

-
URI: -
uri of the file containing the variant (of the given media - type, encoded with the given content encoding). These are - interpreted as URLs relative to the map file; they must be on - the same server (!), and they must refer to files to which the - client would be granted access if they were to be requested - directly. -
Content-type: -
media type --- level may be specified, along with "qs". These - are often referred to as MIME types; typical media types are - image/gif, text/plain, or - text/html; level=3. -
Content-language: -
The language of the variant, specified as an Internet standard - language code (e.g., en for English, - kr for Korean, etc.). -
Content-encoding: -
If the file is compressed, or otherwise encoded, rather than - containing the actual raw data, this says how that was done. - For compressed files (the only case where this generally comes - up), content encoding should be - x-compress, or gzip, as appropriate. -
Content-length: -
The size of the file. Clients can ask to receive a given media - type only if the variant isn't too big; specifying a content - length in the map allows the server to compare against these - thresholds without checking the actual file. -
- -

Multiviews

- -This is a per-directory option, meaning it can be set with an -Options directive within a <Directory> -section in access.conf, or (if AllowOverride -is properly set) in .htaccess files. Note that -Options All does not set MultiViews; you -have to ask for it by name. (Fixing this is a one-line change to -httpd.h). - -

- -The effect of MultiViews is as follows: if the server -receives a request for /some/dir/foo, if -/some/dir has MultiViews enabled, and -/some/dir/foo does *not* exist, then the server reads the -directory looking for files named foo.*, and effectively fakes up a -type map which names all those files, assigning them the same media -types and content-encodings it would have if the client had asked for -one of them by name. It then chooses the best match to the client's -requirements, and forwards them along. - -

- -This applies to searches for the file named by the -DirectoryIndex directive, if the server is trying to -index a directory; if the configuration files specify -

-
-  DirectoryIndex index
-
-
then the server will arbitrate between index.html -and index.html3 if both are present. If neither are -present, and index.cgi is there, the server will run it. - -

- -If one of the files found by the globbing is a CGI script, it's not -obvious what should happen. My code gives that case gets special -treatment --- if the request was a POST, or a GET with QUERY_ARGS or -PATH_INFO, the script is given an extremely high quality rating, and -generally invoked; otherwise it is given an extremely low quality -rating, which generally causes one of the other views (if any) to be -retrieved. This is the only jiggering of quality ratings done by the -MultiViews code; aside from that, all Qualities in the synthesized -type maps are 1.0. - -

- -New as of 0.8: Documents in multiple languages can also be resolved through the use -of the AddLanguage and LanguagePriority -directives: - -

-AddLanguage en .en
-AddLanguage fr .fr
-AddLanguage de .de
-AddLanguage da .da
-AddLanguage el .el
-AddLanguage it .it
-
-# LanguagePriority allows you to give precedence to some languages
-# in case of a tie during content negotiation.
-# Just list the languages in decreasing order of preference.
-
-LanguagePriority en fr de
-
- -Here, a request for "foo.html" matched against "foo.html.en" and -"foo.html.fr" would return an French document to a browser that -indicated a preference for French, or an English document otherwise. -In fact, a request for "foo" matched against "foo.html.en", -"foo.html.fr", "foo.ps.en", "foo.pdf.de", and "foo.txt.it" would do -just what you expect - treat those suffices as a database and compare -the request to it, returning the best match. The languages and data -types share the same suffix name space. - -

- -Note that this machinery only comes into play if the file which the -user attempted to retrieve does not exist by that name; if it -does, it is simply retrieved as usual. (So, someone who actually asks -for foo.jpeg, as opposed to foo, never gets -foo.gif). - - - diff --git a/docs/manual/custom-error.html.en b/docs/manual/custom-error.html.en deleted file mode 100644 index efc3f041e2f..00000000000 --- a/docs/manual/custom-error.html.en +++ /dev/null @@ -1,108 +0,0 @@ - - -Custom error responses - - - - -

Custom error responses

- -
-
Purpose -
Additional functionality. Allows web-masters to configure the response of -Apache to some error or problem.
-

Customizable responses can be defined to be activated in the event of a -server detected error or problem.
-e.g. if a script crashes and produces a "500 Server Error" response, then -this response can be replaced with either some friendlier text or by a -redirection to another URL (local or external). -

Old behavior -
NCSA httpd 1.3 would return some boring old error/problem message which -would often be meaningless to the user, and would provide no means of logging -the symptoms which caused it.

-
New behavior -
The server can be asked to; -
    -
  1. Display some other text, instead of the NCSA hard coded messages, or -
  2. redirect to a local URL, or -
  3. redirect to an external URL. -
-

Redirecting to another URL can be useful, but only if some information -can be passed which can then be used to explain and/or log the error/problem -more clearly.
To achieve this, Apache will define new CGI-like environment -variables, e.g. -

-REDIRECT_HTTP_ACCEPT=*/*, image/gif, image/x-xbitmap, image/jpeg
-REDIRECT_HTTP_USER_AGENT=Mozilla/1.1b2 (X11; I; HP-UX A.09.05 9000/712)
-REDIRECT_PATH=.:/bin:/usr/local/bin:/etc
-REDIRECT_QUERY_STRING=
-REDIRECT_REMOTE_ADDR=121.345.78.123
-REDIRECT_REMOTE_HOST=ooh.ahhh.com
-REDIRECT_SERVER_NAME=crash.bang.edu
-REDIRECT_SERVER_PORT=80
-REDIRECT_SERVER_SOFTWARE=Apache/0.8.15
-REDIRECT_URL=/cgi-bin/buggy.pl
-
- -note the REDIRECT_ prefix.

- -At least REDIRECT_URL and REDIRECT_QUERY_STRING will -be passed to the new URL (assuming it's a cgi-script or a cgi-include). The -other variables will exist only if they existed prior to the error/problem.

- -

Configuration -
file: server configuration
-

Here are some examples... -

-ErrorDocument 500 /cgi-bin/crash-recover
-ErrorDocument 500 "Sorry, our script crashed because %s. Oh dear
-ErrorDocument 500 http://xxx/
-ErrorDocument 404 /Lame_excuses/not_found.html
-ErrorDocument 401 /Subscription/how_to_subscribe.html -
-The syntax is,

-ErrorDocument -<3-digit-code> action

- -where the action can be, -

    -
  1. Text to be displayed.
    Prefix the text with a quote ("). Whatever -follows the quote is displayed. If the error/problem produced any additional -information, it can be specified using %s. -Note: the (") prefix isn't displayed. -
  2. An external URL to redirect to. -
  3. A local URL to redirect to. -
-

ErrorDocument definitions are sensitive to a -SIGHUP, so you can change any of the definitions or add new ones -prior to sending a SIGHUP (kill -1) signal. -

-


- -

Custom error responses and redirects

-
-
Purpose -
Apache's behavior to redirected URLs has been modified so that additional -environment variables are available to a script/server-include.

- -

Old behavior -
Standard CGI vars were made available to a script which has been -redirected to. No indication of where the redirection came from was provided. -

-

New behavior -
A new batch of environment variables will be initialized for use by a -script which has been redirected to.
-Each new variable will have the prefix REDIRECT_.
-REDIRECT_ environment variables are created from the CGI environment -variables which existed prior to the redirect, they are renamed with a -REDIRECT_ prefix, i.e. HTTP_USER_AGENT -> REDIRECT_HTTP_USER_AGENT.
-In addition to these new variables, Apache will define -REDIRECT_URL and REDIRECT_STATUS to help the script -trace its origin.
-Logging: both the original URL and the URL being redirected to, will -now be logged correctly in the access log.

-

- - - - diff --git a/docs/manual/developer/API.html b/docs/manual/developer/API.html deleted file mode 100644 index cf58146e3f5..00000000000 --- a/docs/manual/developer/API.html +++ /dev/null @@ -1,987 +0,0 @@ - -Apache API notes - - - -

Apache API notes

- -These are some notes on the Apache API and the data structures you -have to deal with, etc. They are not yet nearly complete, but -hopefully, they will help you get your bearings. Keep in mind that -the API is still subject to change as we gain experience with it. -(See the TODO file for what might be coming). However, -it will be easy to adapt modules to any changes that are made. -(We have more modules to adapt than you do). -

- -A few notes on general pedagogical style here. In the interest of -conciseness, all structure declarations here are incomplete --- the -real ones have more slots that I'm not telling you about. For the -most part, these are reserved to one component of the server core or -another, and should be altered by modules with caution. However, in -some cases, they really are things I just haven't gotten around to -yet. Welcome to the bleeding edge.

- -Finally, here's an outline, to give you some bare idea of what's -coming up, and in what order: - -

- -

Basic concepts.

- -We begin with an overview of the basic concepts behind the -API, and how they are manifested in the code. - -

Handlers, Modules, and Requests

- -Apache breaks down request handling into a series of steps, more or -less the same way the Netscape server API does (although this API has -a few more stages than NetSite does, as hooks for stuff I thought -might be useful in the future). These are: - - - -These phases are handled by looking at each of a succession of -modules, looking to see if each of them has a handler for the -phase, and attempting invoking it if so. The handler can typically do -one of three things: - - - -Most phases are terminated by the first module that handles them; -however, for logging, `fixups', and non-access authentication -checking, all handlers always run (barring an error). Also, the -response phase is unique in that modules may declare multiple handlers -for it, via a dispatch table keyed on the MIME type of the requested -object. Modules may declare a response-phase handler which can handle -any request, by giving it the key */* (i.e., a -wildcard MIME type specification). However, wildcard handlers are -only invoked if the server has already tried and failed to find a more -specific response handler for the MIME type of the requested object -(either none existed, or they all declined).

- -The handlers themselves are functions of one argument (a -request_rec structure. vide infra), which returns an -integer, as above.

- -

A brief tour of a module

- -At this point, we need to explain the structure of a module. Our -candidate will be one of the messier ones, the CGI module --- this -handles both CGI scripts and the ScriptAlias config file -command. It's actually a great deal more complicated than most -modules, but if we're going to have only one example, it might as well -be the one with its fingers in every place.

- -Let's begin with handlers. In order to handle the CGI scripts, the -module declares a response handler for them. Because of -ScriptAlias, it also has handlers for the name -translation phase (to recognise ScriptAliased URIs), the -type-checking phase (any ScriptAliased request is typed -as a CGI script).

- -The module needs to maintain some per (virtual) -server information, namely, the ScriptAliases in effect; -the module structure therefore contains pointers to a functions which -builds these structures, and to another which combines two of them (in -case the main server and a virtual server both have -ScriptAliases declared).

- -Finally, this module contains code to handle the -ScriptAlias command itself. This particular module only -declares one command, but there could be more, so modules have -command tables which declare their commands, and describe -where they are permitted, and how they are to be invoked.

- -A final note on the declared types of the arguments of some of these -commands: a pool is a pointer to a resource pool -structure; these are used by the server to keep track of the memory -which has been allocated, files opened, etc., either to service a -particular request, or to handle the process of configuring itself. -That way, when the request is over (or, for the configuration pool, -when the server is restarting), the memory can be freed, and the files -closed, en masse, without anyone having to write explicit code to -track them all down and dispose of them. Also, a -cmd_parms structure contains various information about -the config file being read, and other status information, which is -sometimes of use to the function which processes a config-file command -(such as ScriptAlias). - -With no further ado, the module itself: - -

-/* Declarations of handlers. */
-
-int translate_scriptalias (request_rec *);
-int type_scriptalias (request_rec *);
-int cgi_handler (request_rec *);
-
-/* Subsidiary dispatch table for response-phase handlers, by MIME type */
-
-handler_rec cgi_handlers[] = {
-{ "application/x-httpd-cgi", cgi_handler },
-{ NULL }
-};
-
-/* Declarations of routines to manipulate the module's configuration
- * info.  Note that these are returned, and passed in, as void *'s;
- * the server core keeps track of them, but it doesn't, and can't,
- * know their internal structure.
- */
-
-void *make_cgi_server_config (pool *);
-void *merge_cgi_server_config (pool *, void *, void *);
-
-/* Declarations of routines to handle config-file commands */
-
-extern char *script_alias(cmd_parms *, void *per_dir_config, char *fake,
-                          char *real);
-
-command_rec cgi_cmds[] = {
-{ "ScriptAlias", script_alias, NULL, RSRC_CONF, TAKE2,
-    "a fakename and a realname"},
-{ NULL }
-};
-
-module cgi_module = {
-   STANDARD_MODULE_STUFF,
-   NULL,                     /* initializer */
-   NULL,                     /* dir config creator */
-   NULL,                     /* dir merger --- default is to override */
-   make_cgi_server_config,   /* server config */
-   merge_cgi_server_config,  /* merge server config */
-   cgi_cmds,                 /* command table */
-   cgi_handlers,             /* handlers */
-   translate_scriptalias,    /* filename translation */
-   NULL,                     /* check_user_id */
-   NULL,                     /* check auth */
-   NULL,                     /* check access */
-   type_scriptalias,         /* type_checker */
-   NULL,                     /* fixups */
-   NULL                      /* logger */
-};
-
- -

How handlers work

- -The sole argument to handlers is a request_rec structure. -This structure describes a particular request which has been made to -the server, on behalf of a client. In most cases, each connection to -the client generates only one request_rec structure.

- -

A brief tour of the request_rec

- -The request_rec contains pointers to a resource pool -which will be cleared when the server is finished handling the -request; to structures containing per-server and per-connection -information, and most importantly, information on the request itself.

- -The most important such information is a small set of character -strings describing attributes of the object being requested, including -its URI, filename, content-type and content-encoding (these being filled -in by the translation and type-check handlers which handle the -request, respectively).

- -Other commonly used data items are tables giving the MIME headers on -the client's original request, MIME headers to be sent back with the -response (which modules can add to at will), and environment variables -for any subprocesses which are spawned off in the course of servicing -the request. These tables are manipulated using the -table_get and table_set routines.

- -Finally, there are pointers to two data structures which, in turn, -point to per-module configuration structures. Specifically, these -hold pointers to the data structures which the module has built to -describe the way it has been configured to operate in a given -directory (via .htaccess files or -<Directory> sections), for private data it has -built in the course of servicing the request (so modules' handlers for -one phase can pass `notes' to their handlers for other phases). There -is another such configuration vector in the server_rec -data structure pointed to by the request_rec, which -contains per (virtual) server configuration data.

- -Here is an abridged declaration, giving the fields most commonly used:

- -

-struct request_rec {
-
-  pool *pool;
-  conn_rec *connection;
-  server_rec *server;
-
-  /* What object is being requested */
-  
-  char *uri;
-  char *filename;
-  char *path_info;
-  char *args;           /* QUERY_ARGS, if any */
-  struct stat finfo;    /* Set by server core;
-                         * st_mode set to zero if no such file */
-  
-  char *content_type;
-  char *content_encoding;
-  
-  /* MIME header environments, in and out.  Also, an array containing
-   * environment variables to be passed to subprocesses, so people can
-   * write modules to add to that environment.
-   *
-   * The difference between headers_out and err_headers_out is that
-   * the latter are printed even on error, and persist across internal
-   * redirects (so the headers printed for ErrorDocument handlers will
-   * have them).
-   */
-  
-  table *headers_in;
-  table *headers_out;
-  table *err_headers_out;
-  table *subprocess_env;
-
-  /* Info about the request itself... */
-  
-  int header_only;     /* HEAD request, as opposed to GET */
-  char *protocol;      /* Protocol, as given to us, or HTTP/0.9 */
-  char *method;        /* GET, HEAD, POST, etc. */
-  int method_number;   /* M_GET, M_POST, etc. */
-
-  /* Info for logging */
-
-  char *the_request;
-  int bytes_sent;
-
-  /* A flag which modules can set, to indicate that the data being
-   * returned is volatile, and clients should be told not to cache it.
-   */
-
-  int no_cache;
-
-  /* Various other config info which may change with .htaccess files
-   * These are config vectors, with one void* pointer for each module
-   * (the thing pointed to being the module's business).
-   */
-  
-  void *per_dir_config;   /* Options set in config files, etc. */
-  void *request_config;   /* Notes on *this* request */
-  
-};
-
-
- -

Where request_rec structures come from

- -Most request_rec structures are built by reading an HTTP -request from a client, and filling in the fields. However, there are -a few exceptions: - - - -

Handling requests, declining, and returning error codes

- -As discussed above, each handler, when invoked to handle a particular -request_rec, has to return an int to -indicate what happened. That can either be - - - -Note that if the error code returned is REDIRECT, then -the module should put a Location in the request's -headers_out, to indicate where the client should be -redirected to.

- -

Special considerations for response handlers

- -Handlers for most phases do their work by simply setting a few fields -in the request_rec structure (or, in the case of access -checkers, simply by returning the correct error code). However, -response handlers have to actually send a request back to the client.

- -They should begin by sending an HTTP response header, using the -function send_http_header. (You don't have to do -anything special to skip sending the header for HTTP/0.9 requests; the -function figures out on its own that it shouldn't do anything). If -the request is marked header_only, that's all they should -do; they should return after that, without attempting any further -output.

- -Otherwise, they should produce a request body which responds to the -client as appropriate. The primitives for this are rputc -and rprintf, for internally generated output, and -send_fd, to copy the contents of some FILE * -straight to the client.

- -At this point, you should more or less understand the following piece -of code, which is the handler which handles GET requests -which have no more specific handler; it also shows how conditional -GETs can be handled, if it's desirable to do so in a -particular response handler --- set_last_modified checks -against the If-modified-since value supplied by the -client, if any, and returns an appropriate code (which will, if -nonzero, be USE_LOCAL_COPY). No similar considerations apply for -set_content_length, but it returns an error code for -symmetry.

- -

-int default_handler (request_rec *r)
-{
-    int errstatus;
-    FILE *f;
-    
-    if (r->method_number != M_GET) return DECLINED;
-    if (r->finfo.st_mode == 0) return NOT_FOUND;
-
-    if ((errstatus = set_content_length (r, r->finfo.st_size))
-        || (errstatus = set_last_modified (r, r->finfo.st_mtime)))
-        return errstatus;
-    
-    f = fopen (r->filename, "r");
-
-    if (f == NULL) {
-        log_reason("file permissions deny server access",
-                   r->filename, r);
-        return FORBIDDEN;
-    }
-      
-    register_timeout ("send", r);
-    send_http_header (r);
-
-    if (!r->header_only) send_fd (f, r);
-    pfclose (r->pool, f);
-    return OK;
-}
-
- -Finally, if all of this is too much of a challenge, there are a few -ways out of it. First off, as shown above, a response handler which -has not yet produced any output can simply return an error code, in -which case the server will automatically produce an error response. -Secondly, it can punt to some other handler by invoking -internal_redirect, which is how the internal redirection -machinery discussed above is invoked. A response handler which has -internally redirected should always return OK.

- -(Invoking internal_redirect from handlers which are -not response handlers will lead to serious confusion). - -

Special considerations for authentication handlers

- -Stuff that should be discussed here in detail: - - - -

Special considerations for logging handlers

- -When a request has internally redirected, there is the question of -what to log. Apache handles this by bundling the entire chain of -redirects into a list of request_rec structures which are -threaded through the r->prev and r->next -pointers. The request_rec which is passed to the logging -handlers in such cases is the one which was originally built for the -initial request from the client; note that the bytes_sent field will -only be correct in the last request in the chain (the one for which a -response was actually sent). - -

Resource allocation and resource pools

- -One of the problems of writing and designing a server-pool server is -that of preventing leakage, that is, allocating resources (memory, -open files, etc.), without subsequently releasing them. The resource -pool machinery is designed to make it easy to prevent this from -happening, by allowing resource to be allocated in such a way that -they are automatically released when the server is done with -them.

- -The way this works is as follows: the memory which is allocated, file -opened, etc., to deal with a particular request are tied to a -resource pool which is allocated for the request. The pool -is a data structure which itself tracks the resources in question.

- -When the request has been processed, the pool is cleared. At -that point, all the memory associated with it is released for reuse, -all files associated with it are closed, and any other clean-up -functions which are associated with the pool are run. When this is -over, we can be confident that all the resource tied to the pool have -been released, and that none of them have leaked.

- -Server restarts, and allocation of memory and resources for per-server -configuration, are handled in a similar way. There is a -configuration pool, which keeps track of resources which were -allocated while reading the server configuration files, and handling -the commands therein (for instance, the memory that was allocated for -per-server module configuration, log files and other files that were -opened, and so forth). When the server restarts, and has to reread -the configuration files, the configuration pool is cleared, and so the -memory and file descriptors which were taken up by reading them the -last time are made available for reuse.

- -It should be noted that use of the pool machinery isn't generally -obligatory, except for situations like logging handlers, where you -really need to register cleanups to make sure that the log file gets -closed when the server restarts (this is most easily done by using the -function pfopen, which also -arranges for the underlying file descriptor to be closed before any -child processes, such as for CGI scripts, are execed), or -in case you are using the timeout machinery (which isn't yet even -documented here). However, there are two benefits to using it: -resources allocated to a pool never leak (even if you allocate a -scratch string, and just forget about it); also, for memory -allocation, palloc is generally faster than -malloc.

- -We begin here by describing how memory is allocated to pools, and then -discuss how other resources are tracked by the resource pool -machinery. - -

Allocation of memory in pools

- -Memory is allocated to pools by calling the function -palloc, which takes two arguments, one being a pointer to -a resource pool structure, and the other being the amount of memory to -allocate (in chars). Within handlers for handling -requests, the most common way of getting a resource pool structure is -by looking at the pool slot of the relevant -request_rec; hence the repeated appearance of the -following idiom in module code: - -
-int my_handler(request_rec *r)
-{
-    struct my_structure *foo;
-    ...
-
-    foo = (foo *)palloc (r->pool, sizeof(my_structure));
-}
-
- -Note that there is no pfree --- -palloced memory is freed only when the associated -resource pool is cleared. This means that palloc does not -have to do as much accounting as malloc(); all it does in -the typical case is to round up the size, bump a pointer, and do a -range check.

- -(It also raises the possibility that heavy use of palloc -could cause a server process to grow excessively large. There are -two ways to deal with this, which are dealt with below; briefly, you -can use malloc, and try to be sure that all of the memory -gets explicitly freed, or you can allocate a sub-pool of -the main pool, allocate your memory in the sub-pool, and clear it out -periodically. The latter technique is discussed in the section on -sub-pools below, and is used in the directory-indexing code, in order -to avoid excessive storage allocation when listing directories with -thousands of files). - -

Allocating initialized memory

- -There are functions which allocate initialized memory, and are -frequently useful. The function pcalloc has the same -interface as palloc, but clears out the memory it -allocates before it returns it. The function pstrdup -takes a resource pool and a char * as arguments, and -allocates memory for a copy of the string the pointer points to, -returning a pointer to the copy. Finally pstrcat is a -varargs-style function, which takes a pointer to a resource pool, and -at least two char * arguments, the last of which must be -NULL. It allocates enough memory to fit copies of each -of the strings, as a unit; for instance: - -
-     pstrcat (r->pool, "foo", "/", "bar", NULL);
-
- -returns a pointer to 8 bytes worth of memory, initialized to -"foo/bar". - -

Tracking open files, etc.

- -As indicated above, resource pools are also used to track other sorts -of resources besides memory. The most common are open files. The -routine which is typically used for this is pfopen, which -takes a resource pool and two strings as arguments; the strings are -the same as the typical arguments to fopen, e.g., - -
-     ...
-     FILE *f = pfopen (r->pool, r->filename, "r");
-
-     if (f == NULL) { ... } else { ... }
-
- -There is also a popenf routine, which parallels the -lower-level open system call. Both of these routines -arrange for the file to be closed when the resource pool in question -is cleared.

- -Unlike the case for memory, there are functions to close -files allocated with pfopen, and popenf, -namely pfclose and pclosef. (This is -because, on many systems, the number of files which a single process -can have open is quite limited). It is important to use these -functions to close files allocated with pfopen and -popenf, since to do otherwise could cause fatal errors on -systems such as Linux, which react badly if the same -FILE* is closed more than once.

- -(Using the close functions is not mandatory, since the -file will eventually be closed regardless, but you should consider it -in cases where your module is opening, or could open, a lot of files). - -

Other sorts of resources --- cleanup functions

- -More text goes here. Describe the the cleanup primitives in terms of -which the file stuff is implemented; also, spawn_process. - -

Fine control --- creating and dealing with sub-pools, with a note -on sub-requests

- -On rare occasions, too-free use of palloc() and the -associated primitives may result in undesirably profligate resource -allocation. You can deal with such a case by creating a -sub-pool, allocating within the sub-pool rather than the main -pool, and clearing or destroying the sub-pool, which releases the -resources which were associated with it. (This really is a -rare situation; the only case in which it comes up in the standard -module set is in case of listing directories, and then only with -very large directories. Unnecessary use of the primitives -discussed here can hair up your code quite a bit, with very little -gain).

- -The primitive for creating a sub-pool is make_sub_pool, -which takes another pool (the parent pool) as an argument. When the -main pool is cleared, the sub-pool will be destroyed. The sub-pool -may also be cleared or destroyed at any time, by calling the functions -clear_pool and destroy_pool, respectively. -(The difference is that clear_pool frees resources -associated with the pool, while destroy_pool also -deallocates the pool itself. In the former case, you can allocate new -resources within the pool, and clear it again, and so forth; in the -latter case, it is simply gone).

- -One final note --- sub-requests have their own resource pools, which -are sub-pools of the resource pool for the main request. The polite -way to reclaim the resources associated with a sub request which you -have allocated (using the sub_req_lookup_... functions) -is destroy_sub_request, which frees the resource pool. -Before calling this function, be sure to copy anything that you care -about which might be allocated in the sub-request's resource pool into -someplace a little less volatile (for instance, the filename in its -request_rec structure).

- -(Again, under most circumstances, you shouldn't feel obliged to call -this function; only 2K of memory or so are allocated for a typical sub -request, and it will be freed anyway when the main request pool is -cleared. It is only when you are allocating many, many sub-requests -for a single main request that you should seriously consider the -destroy... functions). - -

Configuration, commands and the like

- -One of the design goals for this server was to maintain external -compatibility with the NCSA 1.3 server --- that is, to read the same -configuration files, to process all the directives therein correctly, -and in general to be a drop-in replacement for NCSA. On the other -hand, another design goal was to move as much of the server's -functionality into modules which have as little as possible to do with -the monolithic server core. The only way to reconcile these goals is -to move the handling of most commands from the central server into the -modules.

- -However, just giving the modules command tables is not enough to -divorce them completely from the server core. The server has to -remember the commands in order to act on them later. That involves -maintaining data which is private to the modules, and which can be -either per-server, or per-directory. Most things are per-directory, -including in particular access control and authorization information, -but also information on how to determine file types from suffixes, -which can be modified by AddType and -DefaultType directives, and so forth. In general, the -governing philosophy is that anything which can be made -configurable by directory should be; per-server information is -generally used in the standard set of modules for information like -Aliases and Redirects which come into play -before the request is tied to a particular place in the underlying -file system.

- -Another requirement for emulating the NCSA server is being able to -handle the per-directory configuration files, generally called -.htaccess files, though even in the NCSA server they can -contain directives which have nothing at all to do with access -control. Accordingly, after URI -> filename translation, but before -performing any other phase, the server walks down the directory -hierarchy of the underlying filesystem, following the translated -pathname, to read any .htaccess files which might be -present. The information which is read in then has to be -merged with the applicable information from the server's own -config files (either from the <Directory> sections -in access.conf, or from defaults in -srm.conf, which actually behaves for most purposes almost -exactly like <Directory />).

- -Finally, after having served a request which involved reading -.htaccess files, we need to discard the storage allocated -for handling them. That is solved the same way it is solved wherever -else similar problems come up, by tying those structures to the -per-transaction resource pool.

- -

Per-directory configuration structures

- -Let's look out how all of this plays out in mod_mime.c, -which defines the file typing handler which emulates the NCSA server's -behavior of determining file types from suffixes. What we'll be -looking at, here, is the code which implements the -AddType and AddEncoding commands. These -commands can appear in .htaccess files, so they must be -handled in the module's private per-directory data, which in fact, -consists of two separate tables for MIME types and -encoding information, and is declared as follows: - -
-typedef struct {
-    table *forced_types;      /* Additional AddTyped stuff */
-    table *encoding_types;    /* Added with AddEncoding... */
-} mime_dir_config;
-
- -When the server is reading a configuration file, or -<Directory> section, which includes one of the MIME -module's commands, it needs to create a mime_dir_config -structure, so those commands have something to act on. It does this -by invoking the function it finds in the module's `create per-dir -config slot', with two arguments: the name of the directory to which -this configuration information applies (or NULL for -srm.conf), and a pointer to a resource pool in which the -allocation should happen.

- -(If we are reading a .htaccess file, that resource pool -is the per-request resource pool for the request; otherwise it is a -resource pool which is used for configuration data, and cleared on -restarts. Either way, it is important for the structure being created -to vanish when the pool is cleared, by registering a cleanup on the -pool if necessary).

- -For the MIME module, the per-dir config creation function just -pallocs the structure above, and a creates a couple of -tables to fill it. That looks like this: - -

-void *create_mime_dir_config (pool *p, char *dummy)
-{
-    mime_dir_config *new =
-      (mime_dir_config *) palloc (p, sizeof(mime_dir_config));
-
-    new->forced_types = make_table (p, 4);
-    new->encoding_types = make_table (p, 4);
-    
-    return new;
-}
-
- -Now, suppose we've just read in a .htaccess file. We -already have the per-directory configuration structure for the next -directory up in the hierarchy. If the .htaccess file we -just read in didn't have any AddType or -AddEncoding commands, its per-directory config structure -for the MIME module is still valid, and we can just use it. -Otherwise, we need to merge the two structures somehow.

- -To do that, the server invokes the module's per-directory config merge -function, if one is present. That function takes three arguments: -the two structures being merged, and a resource pool in which to -allocate the result. For the MIME module, all that needs to be done -is overlay the tables from the new per-directory config structure with -those from the parent: - -

-void *merge_mime_dir_configs (pool *p, void *parent_dirv, void *subdirv)
-{
-    mime_dir_config *parent_dir = (mime_dir_config *)parent_dirv;
-    mime_dir_config *subdir = (mime_dir_config *)subdirv;
-    mime_dir_config *new =
-      (mime_dir_config *)palloc (p, sizeof(mime_dir_config));
-
-    new->forced_types = overlay_tables (p, subdir->forced_types,
-                                        parent_dir->forced_types);
-    new->encoding_types = overlay_tables (p, subdir->encoding_types,
-                                          parent_dir->encoding_types);
-
-    return new;
-}
-
- -As a note --- if there is no per-directory merge function present, the -server will just use the subdirectory's configuration info, and ignore -the parent's. For some modules, that works just fine (e.g., for the -includes module, whose per-directory configuration information -consists solely of the state of the XBITHACK), and for -those modules, you can just not declare one, and leave the -corresponding structure slot in the module itself NULL.

- -

Command handling

- -Now that we have these structures, we need to be able to figure out -how to fill them. That involves processing the actual -AddType and AddEncoding commands. To find -commands, the server looks in the module's command table. -That table contains information on how many arguments the commands -take, and in what formats, where it is permitted, and so forth. That -information is sufficient to allow the server to invoke most -command-handling functions with pre-parsed arguments. Without further -ado, let's look at the AddType command handler, which -looks like this (the AddEncoding command looks basically -the same, and won't be shown here): - -
-char *add_type(cmd_parms *cmd, mime_dir_config *m, char *ct, char *ext)
-{
-    if (*ext == '.') ++ext;
-    table_set (m->forced_types, ext, ct);
-    return NULL;
-}
-
- -This command handler is unusually simple. As you can see, it takes -four arguments, two of which are pre-parsed arguments, the third being -the per-directory configuration structure for the module in question, -and the fourth being a pointer to a cmd_parms structure. -That structure contains a bunch of arguments which are frequently of -use to some, but not all, commands, including a resource pool (from -which memory can be allocated, and to which cleanups should be tied), -and the (virtual) server being configured, from which the module's -per-server configuration data can be obtained if required.

- -Another way in which this particular command handler is unusually -simple is that there are no error conditions which it can encounter. -If there were, it could return an error message instead of -NULL; this causes an error to be printed out on the -server's stderr, followed by a quick exit, if it is in -the main config files; for a .htaccess file, the syntax -error is logged in the server error log (along with an indication of -where it came from), and the request is bounced with a server error -response (HTTP error status, code 500).

- -The MIME module's command table has entries for these commands, which -look like this: - -

-command_rec mime_cmds[] = {
-{ "AddType", add_type, NULL, OR_FILEINFO, TAKE2, 
-    "a mime type followed by a file extension" },
-{ "AddEncoding", add_encoding, NULL, OR_FILEINFO, TAKE2, 
-    "an encoding (e.g., gzip), followed by a file extension" },
-{ NULL }
-};
-
- -The entries in these tables are: - - - -Finally, having set this all up, we have to use it. This is -ultimately done in the module's handlers, specifically for its -file-typing handler, which looks more or less like this; note that the -per-directory configuration structure is extracted from the -request_rec's per-directory configuration vector by using -the get_module_config function. - -
-int find_ct(request_rec *r)
-{
-    int i;
-    char *fn = pstrdup (r->pool, r->filename);
-    mime_dir_config *conf = (mime_dir_config *)
-             get_module_config(r->per_dir_config, &mime_module);
-    char *type;
-
-    if (S_ISDIR(r->finfo.st_mode)) {
-        r->content_type = DIR_MAGIC_TYPE;
-        return OK;
-    }
-    
-    if((i=rind(fn,'.')) < 0) return DECLINED;
-    ++i;
-
-    if ((type = table_get (conf->encoding_types, &fn[i])))
-    {
-        r->content_encoding = type;
-
-        /* go back to previous extension to try to use it as a type */
-
-        fn[i-1] = '\0';
-        if((i=rind(fn,'.')) < 0) return OK;
-        ++i;
-    }
-
-    if ((type = table_get (conf->forced_types, &fn[i])))
-    {
-        r->content_type = type;
-    }
-    
-    return OK;
-}
-
-
- -

Side notes --- per-server configuration, virtual servers, etc.

- -The basic ideas behind per-server module configuration are basically -the same as those for per-directory configuration; there is a creation -function and a merge function, the latter being invoked where a -virtual server has partially overridden the base server configuration, -and a combined structure must be computed. (As with per-directory -configuration, the default if no merge function is specified, and a -module is configured in some virtual server, is that the base -configuration is simply ignored).

- -The only substantial difference is that when a command needs to -configure the per-server private module data, it needs to go to the -cmd_parms data to get at it. Here's an example, from the -alias module, which also indicates how a syntax error can be returned -(note that the per-directory configuration argument to the command -handler is declared as a dummy, since the module doesn't actually have -per-directory config data): - -

-char *add_redirect(cmd_parms *cmd, void *dummy, char *f, char *url)
-{
-    server_rec *s = cmd->server;
-    alias_server_conf *conf = (alias_server_conf *)
-            get_module_config(s->module_config,&alias_module);
-    alias_entry *new = push_array (conf->redirects);
-
-    if (!is_url (url)) return "Redirect to non-URL";
-    
-    new->fake = f; new->real = url;
-    return NULL;
-}
-
- - - diff --git a/docs/manual/handler.html.en b/docs/manual/handler.html.en deleted file mode 100644 index ea0f61c7e90..00000000000 --- a/docs/manual/handler.html.en +++ /dev/null @@ -1,134 +0,0 @@ - - - -Apache's Handler Use - - - - -

Apache's Handler Use

- -

What is a Handler

- -

A "handler" is an internal Apache representation of the action to be -performed when a file is called. Generally, files have implicit -handlers, based on the file type. Normally, all files are simply -served by the server, but certain file typed are "handled" -separately. For example, you may use a type of -"application/x-httpd-cgi" to invoke CGI scripts.

- -

Apache 1.1 adds the additional ability to use handlers -explicitly. Either based on filename extensions or on location, these -handlers are unrelated to file type. This is advantageous both because -it is a more elegant solution, but it also allows for both a type -and a handler to be associated with a file.

- -

Handlers can either be built into the server or to a module, or -they can be added with the Action directive. The built-in -handlers in the standard distribution are as follows:

- - - -

- -

Directives

- - -
- -

AddHandler

- -Syntax: <AddHandler handler-name extension>
-Context: server config, virtual host, directory, .htaccess
-Status: Base
-Module: mod_mime - -

AddHandler maps the filename extension extension to the -handler handler-name. For example, to activate CGI scripts -with the file extension ".cgi", you might use: -

-    AddHandler cgi-script cgi
-
- -

Once that has been put into your srm.conf or httpd.conf file, any -file ending with ".cgi" will be treated as a CGI -program.

- -
- -

SetHandler

- -Syntax: <SetHandler handler-name>
-Context: directory, .htaccess
-Status: Base
-Module: mod_mime - -

When placed into an .htaccess file or a -<Directory> or <Location section, -this directive forces all matching files to be parsed through the -handler given by handler-name. For example, if you had a -directory you wanted to be parsed entirely as imagemap rule files, -regardless of extension, you might put the following into an -.htaccess file in that directory: -

-    SetHandler imap-file
-
-

Another example: if you wanted to have the server display a status -report whenever a URL of http://servername/status was -called, you might put the following into access.conf: -

-    <Location /status>
-    SetHandler server-status
-    </Location>
-
- -


- -

Programmer's Note

- -

In order to implement the handler features, an addition has been -made to the Apache API that you may wish to -make use of. Specifically, a new record has been added to the -request_rec structure:

-
-    char *handler
-
-

If you wish to have your module engage a handler, you need only to -set r->handler to the name of the handler at any time -prior to the invoke_handler stage of the -request. Handlers are implemented as they were before, albeit using -the handler name instead of a content type. While it is not -necessary, the naming convention for handlers is to use a -dash-separated word, with no slashes, so as to not invade the media -type name-space.

- - - - - diff --git a/docs/manual/install.html.en b/docs/manual/install.html.en deleted file mode 100644 index 4c255ef5d79..00000000000 --- a/docs/manual/install.html.en +++ /dev/null @@ -1,118 +0,0 @@ - - - -Compiling and Installing Apache - - - - -

Compiling and Installing Apache 1.2

-If you wish to download and install an earlier version of Apache please -read Compiling and Installing Apache 1.1. - -

Downloading Apache

-Information on the latest version of Apache can be found on the Apache -web server at -http://www.apache.org/. -This will list the current release, -any more recent beta-test release, together with details of mirror -web and anonymous ftp sites. - -

Compiling Apache

-This release of Apache supports the notion of `optional modules'. -However, the server has to know which modules are compiled into it, in -order for those modules to be effective; this requires generation of a -short bit of code (`modules.c') which simply has a list of them. -

-It is also necessary to choose the correct options for your platform. - -To do this: -

    -
  1. -Copy the file "Configuration.tmpl" to -"Configuration" and then edit -"Configuration". This contains the list and settings of various -"Rules" and an additional section at the bottom which -lists the modules which have been compiled in, and also names the -files containing them. You will need to: -

    - Note that DBM auth has to be explicitly configured in, if you want - it --- just uncomment the corresponding line. - - -

  2. Run the "Configure" script: -
    -      % Configure
    -      Using 'Configuration' as config file
    -       + configured for  platform
    -       + setting C compiler to  *
    -       + setting C compiler optimization-level to  *
    -      %
    -
    - This generates new versions of the Makefile and of modules.c. (If - you want to maintain multiple configurations, you can say, e.g., -
    -      % Configure -file Configuration.ai
    -      Using alternate config file Configuration.ai
    -       + configured for  platform
    -       + setting C compiler to  *
    -       + setting C compiler optimization-level to  *
    -      % 
    -

    -*: Depending on Configuration and your system, Configure - make not print these lines. That's OK - -

  3. Type "make". -

    -The modules we place in the Apache distribution are the ones we have -tested and are used regularly by various members of the Apache -development group. Additional modules contributed by members or third -parties with specific needs or functions are available at -. -There are -instructions on that page for linking these modules into the -core Apache code. -

-

Installing Apache

-After compilation, you will have a binary called `httpd' in the -src/ directory. A binary distribution of Apache will supply this -file. -

-The next step is to edit the configuration files for the server. In -the subdirectory called `conf' you should find distribution versions -of the three configuration files: srm.conf-dist, -access.conf-dist and httpd.conf-dist. Copy them to -srm.conf, access.conf and httpd.conf -respectively. -

-First edit httpd.conf. This sets up general attributes about the -server; the port number, the user it runs as, etc. Next edit the -srm.conf file; this sets up the root of the document tree, -special functions like server-parsed HTML or internal imagemap parsing, etc. -Finally, edit the access.conf file to at least set the base cases -of access. -

-Finally, make a call to httpd, with a -f to the full path to the -httpd.conf file. I.e., the common case: -

- /usr/local/etc/apache/src/httpd -f /usr/local/etc/apache/conf/httpd.conf -
-The server should be now running. -

-By default the srm.conf and access.conf files are -located by name; to specifically call them by other names, use the -AccessConfig and -ResourceConfig directives in -httpd.conf. - - - - diff --git a/docs/manual/invoking.html.en b/docs/manual/invoking.html.en deleted file mode 100644 index 73c570016aa..00000000000 --- a/docs/manual/invoking.html.en +++ /dev/null @@ -1,109 +0,0 @@ - - - -Starting Apache - - - - -

Starting Apache

- -

Invoking Apache

-The httpd program is usually run as a daemon which executes -continuously, handling requests. It is possible to invoke Apache by -the Internet daemon inetd each time a connection to the HTTP -service is made (use the -ServerType directive) -but this is not recommended. - -

Command line options

-The following options are recognized on the httpd command line: -
-
-d serverroot -
Set the initial value for the -ServerRoot variable to -serverroot. This can be overridden by the ServerRoot command in the -configuration file. The default is /usr/local/etc/httpd. - -
-f config -
Execute the commands in the file config on startup. If -config does not begin with a /, then it is taken to be a -path relative to the ServerRoot. The -default is conf/httpd.conf. - -
-X -
Run in single-process mode, for internal debugging purposes only; the -daemon does not detach from the terminal or fork any children. Do NOT -use this mode to provide ordinary web service. - -
-v -
Print the version of httpd, and then exit. - -
-h -
Give a list of directives together with expected arguments and -places where the directive is valid - -
-l -
Give a list of all modules compiled into the server - -
-? -
Print a list of the httpd options, and then exit. -
- -

Configuration files

-The server will read three files for configuration directives. Any directive -may appear in any of these files. The the names of these files are taken -to be relative to the server root; this is set by the -ServerRoot directive, or the --d command line flag. - -Conventionally, the files are: -
-
conf/httpd.conf -
Contains directives that control the operation of the server daemon. -The filename may be overridden with the -f command line flag. - -
conf/srm.conf -
Contains directives that control the specification of documents that -the server can provide to clients. The filename may be overridden with -the ResourceConfig directive. - -
conf/access.conf -
Contains directives that control access to documents. -The filename may be overridden with the -AccessConfig directive. -
-However, these conventions need not be adhered to. -

-The server also reads a file containing mime document types; the filename -is set by the TypesConfig directive, -and is conf/mime.types by default. - -

Log files

-

pid file

-On daemon startup, it saves the process id of the parent httpd process to -the file logs/httpd.pid. This filename can be changed with the -PidFile directive. The process-id is for -use by the administrator in restarting and terminating the daemon; -A HUP signal causes the daemon to re-read its configuration files and -a TERM signal causes it to die gracefully. -

-If the process dies (or is killed) abnormally, then it will be necessary to -kill the children httpd processes. - -

Error log

-The server will log error messages to a log file, logs/error_log -by default. The filename can be set using the -ErrorLog directive; different error logs can -be set for different virtual hosts. - -

Transfer log

-The server will typically log each request to a transfer file, -logs/access_log by default. The filename can be set using a -TransferLog directive; different -transfer logs can be set for different virtual -hosts. - - - - diff --git a/docs/manual/platform/perf-bsd44.html b/docs/manual/platform/perf-bsd44.html deleted file mode 100644 index cc8eca733c9..00000000000 --- a/docs/manual/platform/perf-bsd44.html +++ /dev/null @@ -1,213 +0,0 @@ - - -Running a High-Performance Web Server for BSD - - - - - - -

Running a High-Performance Web Server for BSD

- -Like other OS's, the listen queue is often the first limit hit. The -following are comments from "Aaron Gifford <agifford@InfoWest.COM>" -on how to fix this on BSDI 1.x, 2.x, and FreeBSD 2.0 (and earlier): - -

- -Edit the following two files: -

/usr/include/sys/socket.h
- /usr/src/sys/sys/socket.h
-In each file, look for the following: -
-    /*
-     * Maximum queue length specifiable by listen.
-     */
-    #define SOMAXCONN       5
-
- -Just change the "5" to whatever appears to work. I bumped the two -machines I was having problems with up to 32 and haven't noticed the -problem since. - -

- -After the edit, recompile the kernel and recompile the Apache server -then reboot. - -

- -FreeBSD 2.1 seems to be perfectly happy, with SOMAXCONN -set to 32 already. - -

- - -Addendum for very heavily loaded BSD servers
-
-from Chuck Murcko <chuck@telebase.com> - -

- -If you're running a really busy BSD Apache server, the following are useful -things to do if the system is acting sluggish:

- -

- -These utilities give you an idea what you'll need to tune in your kernel, -and whether it'll help to buy more RAM. - -Here are some BSD kernel config parameters (actually BSDI, but pertinent to -FreeBSD and other 4.4-lite derivatives) from a system getting heavy usage. -The tools mentioned above were used, and the system memory was increased to -48 MB before these tuneups. Other system parameters remained unchanged. - -

- -

-maxusers        256
-
- -Maxusers drives a lot of other kernel parameters: - - - -The actual formulae for these derived parameters are in -/usr/src/sys/conf/param.c. -These calculated parameters can also be overridden (in part) by specifying -your own values in the kernel configuration file: - -
-# Network options. NMBCLUSTERS defines the number of mbuf clusters and
-# defaults to 256. This machine is a server that handles lots of traffic,
-# so we crank that value.
-options         SOMAXCONN=256           # max pending connects
-options         NMBCLUSTERS=4096        # mbuf clusters at 4096
-
-#
-# Misc. options
-#
-options         CHILD_MAX=512           # maximum number of child processes
-options         OPEN_MAX=512            # maximum fds (breaks RPC svcs)
-
- -SOMAXCONN is not derived from maxusers, so you'll always need to increase -that yourself. We used a value guaranteed to be larger than Apache's -default for the listen() of 128, currently. - -

- -In many cases, NMBCLUSTERS must be set much larger than would appear -necessary at first glance. The reason for this is that if the browser -disconnects in mid-transfer, the socket fd associated with that particular -connection ends up in the TIME_WAIT state for several minutes, during -which time its mbufs are not yet freed. - -

- -Some more info on mbuf clusters (from sys/mbuf.h): -

-/*
- * Mbufs are of a single size, MSIZE (machine/machparam.h), which
- * includes overhead.  An mbuf may add a single "mbuf cluster" of size
- * MCLBYTES (also in machine/machparam.h), which has no additional overhead
- * and is used instead of the internal data area; this is done when
- * at least MINCLSIZE of data must be stored.
- */
-
- -

- -CHILD_MAX and OPEN_MAX are set to allow up to 512 child processes (different -than the maximum value for processes per user ID) and file descriptors. -These values may change for your particular configuration (a higher OPEN_MAX -value if you've got modules or CGI scripts opening lots of connections or -files). If you've got a lot of other activity besides httpd on the same -machine, you'll have to set NPROC higher still. In this example, the NPROC -value derived from maxusers proved sufficient for our load. - -

- -Caveats - -

- -Be aware that your system may not boot with a kernel that is configured -to use more resources than you have available system RAM. ALWAYS -have a known bootable kernel available when tuning your system this way, -and use the system tools beforehand to learn if you need to buy more -memory before tuning. - -

- -RPC services will fail when the value of OPEN_MAX is larger than 256. -This is a function of the original implementations of the RPC library, -which used a byte value for holding file descriptors. BSDI has partially -addressed this limit in its 2.1 release, but a real fix may well await -the redesign of RPC itself. - -

- -Finally, there's the hard limit of child processes configured in Apache. - -

- -For versions of Apache later than 1.0.5 you'll need to change the -definition for HARD_SERVER_LIMIT in httpd.h and recompile -if you need to run more than the default 150 instances of httpd. - -

- -From conf/httpd.conf-dist: - -

-# Limit on total number of servers running, i.e., limit on the number
-# of clients who can simultaneously connect --- if this limit is ever
-# reached, clients will be LOCKED OUT, so it should NOT BE SET TOO LOW.
-# It is intended mainly as a brake to keep a runaway server from taking
-# Unix with it as it spirals down...
-
-MaxClients 150
-
- -Know what you're doing if you bump this value up, and make sure you've -done your system monitoring, RAM expansion, and kernel tuning beforehand. -Then you're ready to service some serious hits! - -

- -Thanks to Tony Sanders and Chris Torek at BSDI for their -helpful suggestions and information. - -


- -

More welcome!

- -If you have tips to contribute, send mail to brian@organic.com - - - - diff --git a/docs/manual/platform/perf-dec.html b/docs/manual/platform/perf-dec.html deleted file mode 100644 index ef75f81b06c..00000000000 --- a/docs/manual/platform/perf-dec.html +++ /dev/null @@ -1,271 +0,0 @@ - -Performance Tuning Tips for Digital Unix - - - -

Performance Tuning Tips for Digital Unix

- -Below is a set of newsgroup posts made by an engineer from DEC in -response to queries about how to modify DEC's Digital Unix OS for more -heavily loaded web sites. Copied with permission. - -
- -

Update

-From: Jeffrey Mogul
-Date: Fri, 28 Jun 96 16:07:56 MDT
- -
    -
  1. The advice given in the README file regarding the - "tcbhashsize" variable is incorrect. The largest value - this should be set to is 1024. Setting it any higher - will have the perverse result of disabling the hashing - mechanism. - -
  2. Patch ID OSF350-146 has been superseded by -
    - Patch ID OSF350-195 for V3.2C
    - Patch ID OSF360-350195 for V3.2D -
    - Patch IDs for V3.2E and V3.2F should be available soon. - There is no known reason why the Patch ID OSF360-350195 - won't work on these releases, but such use is not officially - supported by Digital. This patch kit will not be needed for - V3.2G when it is released. - - -
    - - -
    -From           mogul@pa.dec.com (Jeffrey Mogul)
    -Organization   DEC Western Research
    -Date           30 May 1996 00:50:25 GMT
    -Newsgroups     comp.unix.osf.osf1
    -Message-ID     <4oirch$bc8@usenet.pa.dec.com>
    -Subject        Re: Web Site Performance
    -References     1
    -
    -
    -
    -In article <skoogDs54BH.9pF@netcom.com> skoog@netcom.com (Jim Skoog) writes:
    ->Where are the performance bottlenecks for Alpha AXP running the
    ->Netscape Commerce Server 1.12 with high volume internet traffic?
    ->We are evaluating network performance for a variety of Alpha AXP
    ->runing DEC UNIX 3.2C, which run DEC's seal firewall and behind
    ->that Alpha 1000 and 2100 webservers.
    -
    -Our experience (running such Web servers as altavista.digital.com
    -and www.digital.com) is that there is one important kernel tuning
    -knob to adjust in order to get good performance on V3.2C.  You
    -need to patch the kernel global variable "somaxconn" (use dbx -k
    -to do this) from its default value of 8 to something much larger.
    -
    -How much larger?  Well, no larger than 32767 (decimal).  And
    -probably no less than about 2048, if you have a really high volume
    -(millions of hits per day), like AltaVista does.
    -
    -This change allows the system to maintain more than 8 TCP
    -connections in the SYN_RCVD state for the HTTP server.  (You
    -can use "netstat -An |grep SYN_RCVD" to see how many such
    -connections exist at any given instant).
    -
    -If you don't make this change, you might find that as the load gets
    -high, some connection attempts take a very long time.  And if a lot
    -of your clients disconnect from the Internet during the process of
    -TCP connection establishment (this happens a lot with dialup
    -users), these "embryonic" connections might tie up your somaxconn
    -quota of SYN_RCVD-state connections.  Until the kernel times out
    -these embryonic connections, no other connections will be accepted,
    -and it will appear as if the server has died.
    -
    -The default value for somaxconn in Digital UNIX V4.0 will be quite
    -a bit larger than it has been in previous versions (we inherited
    -this default from 4.3BSD).
    -
    -Digital UNIX V4.0 includes some other performance-related changes
    -that significantly improve its maximum HTTP connection rate.  However,
    -we've been using V3.2C systems to front-end for altavista.digital.com
    -with no obvious performance bottlenecks at the millions-of-hits-per-day
    -level.
    -
    -We have some Webstone performance results available at
    -        http://www.digital.com/info/alphaserver/news/webff.html
    -I'm not sure if these were done using V4.0 or an earlier version
    -of Digital UNIX, although I suspect they were done using a test
    -version of V4.0.
    -
    --Jeff
    -
    -
    - ----------------------------------------------------------------------------- - -From mogul@pa.dec.com (Jeffrey Mogul) -Organization DEC Western Research -Date 31 May 1996 21:01:01 GMT -Newsgroups comp.unix.osf.osf1 -Message-ID <4onmmd$mmd@usenet.pa.dec.com> -Subject Digital UNIX V3.2C Internet tuning patch info - ----------------------------------------------------------------------------- - -Something that probably few people are aware of is that Digital -has a patch kit available for Digital UNIX V3.2C that may improve -Internet performance, especially for busy web servers. - -This patch kit is one way to increase the value of somaxconn, -which I discussed in a message here a day or two ago. - -I've included in this message the revised README file for this -patch kit below. Note that the original README file in the patch -kit itself may be an earlier version; I'm told that the version -below is the right one. - -Sorry, this patch kit is NOT available for other versions of Digital -UNIX. Most (but not quite all) of these changes also made it into V4.0, -so the description of the various tuning parameters in this README -file might be useful to people running V4.0 systems. - -This patch kit does not appear to be available (yet?) from - http://www.service.digital.com/html/patch_service.html -so I guess you'll have to call Digital's Customer Support to get it. - --Jeff - -DESCRIPTION: Digital UNIX Network tuning patch - - Patch ID: OSF350-146 - - SUPERSEDED PATCHES: OSF350-151, OSF350-158 - - This set of files improves the performance of the network - subsystem on a system being used as a web server. There are - additional tunable parameters included here, to be used - cautiously by an informed system administrator. - -TUNING - - To tune the web server, the number of simultaneous socket - connection requests are limited by: - - somaxconn Sets the maximum number of pending requests - allowed to wait on a listening socket. The - default value in Digital UNIX V3.2 is 8. - This patch kit increases the default to 1024, - which matches the value in Digital UNIX V4.0. - - sominconn Sets the minimum number of pending connections - allowed on a listening socket. When a user - process calls listen with a backlog less - than sominconn, the backlog will be set to - sominconn. sominconn overrides somaxconn. - The default value is 1. - - The effectiveness of tuning these parameters can be monitored by - the sobacklog variables available in the kernel: - - sobacklog_hiwat Tracks the maximum pending requests to any - socket. The initial value is 0. - - sobacklog_drops Tracks the number of drops exceeding the - socket set backlog limit. The initial - value is 0. - - somaxconn_drops Tracks the number of drops exceeding the - somaxconn limit. When sominconn is larger - than somaxconn, tracks the number of drops - exceeding sominconn. The initial value is 0. - - TCP timer parameters also affect performance. Tuning the following - require some knowledge of the characteristics of the network. - - tcp_msl Sets the tcp maximum segment lifetime. - This is the maximum lifetime in half - seconds that a packet can be in transit - on the network. This value, when doubled, - is the length of time a connection remains - in the TIME_WAIT state after a incoming - close request is processed. The unit is - specified in 1/2 seconds, the initial - value is 60. - - tcp_rexmit_interval_min - Sets the minimum TCP retransmit interval. - For some WAN networks the default value may - be too short, causing unnecessary duplicate - packets to be sent. The unit is specified - in 1/2 seconds, the initial value is 1. - - tcp_keepinit This is the amount of time a partially - established connection will sit on the listen - queue before timing out (e.g. if a client - sends a SYN but never answers our SYN/ACK). - Partially established connections tie up slots - on the listen queue. If the queue starts to - fill with connections in SYN_RCVD state, - tcp_keepinit can be decreased to make those - partial connects time out sooner. This should - be used with caution, since there might be - legitimate clients that are taking a while - to respond to SYN/ACK. The unit is specified - in 1/2 seconds, the default value is 150 - (ie. 75 seconds). - - The hashlist size for the TCP inpcb lookup table is regulated by: - - tcbhashsize The number of hash buckets used for the - TCP connection table used in the kernel. - The initial value is 32. For best results, - should be specified as a power of 2. For - busy Web servers, set this to 2048 or more. - - The hashlist size for the interface alias table is regulated by: - - inifaddr_hsize The number of hash buckets used for the - interface alias table used in the kernel. - The initial value is 32. For best results, - should be specified as a power of 2. - - ipport_userreserved The maximum number of concurrent non-reserved, - dynamically allocated ports. Default range - is 1025-5000. The maximum value is 65535. - This limits the numer of times you can - simultaneously telnet or ftp out to connect - to other systems. - - tcpnodelack Don't delay acknowledging TCP data; this - can sometimes improve performance of locally - run CAD packages. Default is value is 0, - the enabled value is 1. - - Digital UNIX version: - - V3.2C -Feature V3.2C patch V4.0 - ======= ===== ===== ==== -somaxconn X X X -sominconn - X X -sobacklog_hiwat - X - -sobacklog_drops - X - -somaxconn_drops - X - -tcpnodelack X X X -tcp_keepidle X X X -tcp_keepintvl X X X -tcp_keepcnt - X X -tcp_keepinit - X X -TCP keepalive per-socket - - X -tcp_msl - X - -tcp_rexmit_interval_min - X - -TCP inpcb hashing - X X -tcbhashsize - X X -interface alias hashing - X X -inifaddr_hsize - X X -ipport_userreserved - X - -sysconfig -q inet - - X -sysconfig -q socket - - X - -
    - - - diff --git a/docs/manual/platform/perf.html b/docs/manual/platform/perf.html deleted file mode 100644 index fe99016809d..00000000000 --- a/docs/manual/platform/perf.html +++ /dev/null @@ -1,132 +0,0 @@ - - - -Hints on Running a High-Performance Web Server - - - - -

    Hints on Running a High-Performance Web Server

    - -Running Apache on a heavily loaded web server, one often encounters -problems related to the machine and OS configuration. "Heavy" is -relative, of course - but if you are seeing more than a couple hits -per second on a sustained basis you should consult the pointers on -this page. In general the suggestions involve how to tune your kernel -for the heavier TCP load, hardware/software conflicts that arise, etc. - - - -
    - - -

    A/UX (Apple's UNIX)

    -
    - -If you are running Apache on A/UX, a page that gives some helpful -performance hints (concerning the listen() queue and using -virtual hosts) -can be found here - -


    - - -

    BSD-based (BSDI, FreeBSD, etc)

    -
    - -Quick and -detailed -performance tuning hints for BSD-derived systems. - -


    - - -

    Digital UNIX

    -
    - -We have some newsgroup postings on how to -tune Digital UNIX 3.2 and 4.0. - -


    - - -

    Hewlett-Packard

    -
    - -Some documentation on tuning HP machines can be found at http://www.software.hp.com/internet/perf/tuning.html. - -


    - - -

    Linux

    -
    - -The most common problem on Linux shows up on heavily-loaded systems -where the whole server will appear to freeze for a couple of minutes -at a time, and then come back to life. This has been traced to a -listen() queue overload - certain Linux implementations have a low -value set for the incoming connection queue which can cause problems. -Please see our Using Apache on -Linux page for more info on how to fix this. - -


    - - -

    SGI

    - -
    - -


    - - -

    Solaris 2.4

    -
    - -The Solaris 2.4 TCP implementation has a few inherent limitations that -only became apparent under heavy loads. This has been fixed to some -extent in 2.5 (and completely revamped in 2.6), but for now consult -the following URL for tips on how to expand the capabilities if you -are finding slowdowns and lags are hurting performance. - - - -


    - - -

    SunOS 4.x

    -
    - -More information on tuning SOMAXCONN on SunOS can be found at - -http://www.islandnet.com/~mark/somaxconn.html. - -


    - -

    More welcome!

    - -If you have tips to contribute, send mail to brian@organic.com - - - - diff --git a/docs/manual/suexec.html.en b/docs/manual/suexec.html.en deleted file mode 100644 index 4e252237b9c..00000000000 --- a/docs/manual/suexec.html.en +++ /dev/null @@ -1,164 +0,0 @@ - -Apache SetUserID Support - - - -

    Apache suEXEC Support

    - -
    - -

    What is suEXEC?

    -The suEXEC feature, introduced in Apache 1.2 provides the ability to -run CGI programs under user ids different from the user id of the -calling web-server. Used properly, this feature can reduce considerably the -insecurity of allowing users to run CGI programs. At the same time, improperly -configured, this facility can crash your computer, burn your house down and -steal all the money from your retirement fund. :-) If you aren't -familiar with managing setuid root programs and the security issues they -present, we highly recommend that you not consider using this feature.

    - -


    - -

    Enabling suEXEC Support

    -Having said all that, enabling this feature is purposefully difficult with -the intent that it will only be installed by users determined to use it and -is not part of the normal install/compile process.

    - -

      -

      Configuring the suEXEC wrapper

      -From the top-level of the Apache source tree, type:  cd support [ENTER]

      -Edit the suexec.h file and change the following macros to match your -local Apache installation.

      -From support/suexec.h - -

      -/*
      - * HTTPD_USER -- Define as the username under which Apache normally
      - *               runs.  This is the only user allowed to execute
      - *               this program.
      - */
      -#define HTTPD_USER "www"
      -
      -/*
      - * LOG_EXEC -- Define this as a filename if you want all suEXEC
      - *             transactions and errors logged for auditing and
      - *             debugging purposes.
      - */
      -#define LOG_EXEC "/usr/local/etc/httpd/logs/cgi.log"
      -
      -/*
      - * DOC_ROOT -- Define as the DocumentRoot set for Apache.  This
      - *             will be the only hierarchy (aside from UserDirs)
      - *             that can be used for suEXEC behavior.
      - */
      -#define DOC_ROOT "/usr/local/etc/httpd/htdocs"
      -
      -/*
      - * NNAME -- Define this as the name for the nobody account
      - *          on your operating system.  Most systems will just
      - *          need the default 'nobody'.
      - */
      -#define NNAME "nobody"
      -
      -/* NGID -- Define this as the *number* for the nogroup group
      - *         on your operating system.  Most systems will have
      - *         a -1 or -2.  Others might have something above
      - *         65000.
      - */
      -#define NGID -1
      -
      - - -

      Compiling the suEXEC wrapper

      -At the shell command prompt, type:  cc suexec.c -o suexec [ENTER].

      -This should create the suexec wrapper executable. - -

      Compiling Apache for suEXEC support

      -By default, Apache is compiled to look for the suEXEC wrapper in the following -location.

      -From src/httpd.h - -

      -/* The path to the suEXEC wrapper */
      -#ifndef SUEXEC_BIN
      -#define SUEXEC_BIN "/usr/local/etc/httpd/sbin/suexec"
      -#endif
      -
      - -

      -If your installation requires location of the wrapper program in a different -directory, edit src/httpd.h and recompile your Apache server. See Compiling and Installing Apache for more info on this process.

      - -

      Installing the suEXEC wrapper

      -Copy the suexec executable created in the exercise above to the defined -location for SUEXEC_BIN.

      -In order for the wrapper to set the user id for execution requests it must me installed -as owner root and must have the setuserid execution bit set for file modes. -If you are not running a root user shell, do so now and execute the following -commands.

      - -chown root /usr/local/etc/httpd/sbin/suexec [ENTER]

      -chmod 4711 /usr/local/etc/httpd/sbin/suexec [ENTER]

      - -Change the path to the suEXEC wrapper to match your system installation. -

    - -
    - - -

    Security Model of suEXEC

    -The suEXEC wrapper supplied with Apache performs the following security -checks before it will execute any program passed to it for execution. -
      -
    1. User executing the wrapper must be a valid user on this system. -
    2. User executing the wrapper must be the compiled in HTTPD_USER. -
    3. The command that the request wishes to execute must not contain a /. -
    4. The command being executed must reside under the compiled in DOC_ROOT. -
    5. The current working directory must be a directory. -
    6. The current working directory must not be writable by group or other. -
    7. The command being executed cannot be a symbolic link. -
    8. The command being executed cannot be writable by group or other. -
    9. The command being executed cannot be a setuid or setgid program. -
    10. The target UID and GID must be a valid user and group on this system. -
    11. The target UID and GID to execute as, must match the UID and GID of the directory. -
    12. The target execution UID and GID must not be the privledged ID 0. -
    13. Group access list is set to NOGROUP and the command is executed. -
    -If any of these issues are too restrictive, or do not seem restrictive enough, you are -welcome to install your own version of the wrapper. We've given you the rope, now go -have fun with it. :-) - -
    - -

    Using suEXEC

    -After properly installing the suexec wrapper executable, you must kill and restart -the Apache server. A simple kill -1 `cat httpd.pid` will not be enough. -Upon startup of the web-server, if Apache finds a properly configured suexec wrapper, -it will print the following message to the console.

    - -Configuring Apache for use with suexec wrapper.

    - -If you don't see this message at server startup, the server is most likely not finding the -wrapper program where it expects it, or the executable is not installed setuid root. Check your installation and try again.

    - -One way to use suEXEC is through the User and Group directives in VirtualHost definitions. By setting these directives to values -different from the main server user id, all requests for CGI resources will be executed as -the User and Group defined for that <VirtualHost>. If only one or -neither of these directives are specified for a <VirtualHost> then the main -server userid is assumed.

    - -suEXEC can also be used to to execute CGI programs as the user to which the request -is being directed. This is accomplished by using the ~ character prefixing the -user id for whom execution is desired. The only requirement needed for this feature to work -is for CGI execution to be enabled for the user and that the script must meet the scrutiny of the security checks above. - -


    - -

    Debugging suEXEC

    -The suEXEC wrapper will write log information to the location defined in the suexec.h as indicated above. If you feel you have configured and installed the wrapper properly, -have a look at this log and the error_log for the server to see where you may have gone astray. - - - - -