/* Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. * The ASF licenses this file to You under the Apache License, Version 2.0 * (the "License"); you may not use this file except in compliance with * the License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ /* * Apache example module. Provide demonstrations of how modules do things. * It is not meant to be used in a production server. Since it participates * in all of the processing phases, it could conceivable interfere with * the proper operation of other modules -- particularly the ones related * to security. * * In the interest of brevity, all functions and structures internal to * this module, but which may have counterparts in *real* modules, are * prefixed with 'x_' instead of 'example_'. */ #include "httpd.h" #include "http_config.h" #include "http_core.h" #include "http_log.h" #include "http_main.h" #include "http_protocol.h" #include "http_request.h" #include "util_script.h" #include "http_connection.h" #include "apr_strings.h" #include /*--------------------------------------------------------------------------*/ /* */ /* Data declarations. */ /* */ /* Here are the static cells and structure declarations private to our */ /* module. */ /* */ /*--------------------------------------------------------------------------*/ /* * Sample configuration record. Used for both per-directory and per-server * configuration data. * * It's perfectly reasonable to have two different structures for the two * different environments. The same command handlers will be called for * both, though, so the handlers need to be able to tell them apart. One * possibility is for both structures to start with an int which is 0 for * one and 1 for the other. * * Note that while the per-directory and per-server configuration records are * available to most of the module handlers, they should be treated as * READ-ONLY by all except the command and merge handlers. Sometimes handlers * are handed a record that applies to the current location by implication or * inheritance, and modifying it will change the rules for other locations. */ typedef struct x_cfg { int cmode; /* Environment to which record applies * (directory, server, or combination). */ #define CONFIG_MODE_SERVER 1 #define CONFIG_MODE_DIRECTORY 2 #define CONFIG_MODE_COMBO 3 /* Shouldn't ever happen. */ int local; /* Boolean: "Example" directive declared * here? */ int congenital; /* Boolean: did we inherit an "Example"? */ char *trace; /* Pointer to trace string. */ char *loc; /* Location to which this record applies. */ } x_cfg; /* * Let's set up a module-local static cell to point to the accreting callback * trace. As each API callback is made to us, we'll tack on the particulars * to whatever we've already recorded. To avoid massive memory bloat as * directories are walked again and again, we record the routine/environment * the first time (non-request context only), and ignore subsequent calls for * the same routine/environment. */ static const char *trace = NULL; static apr_table_t *static_calls_made = NULL; /* * To avoid leaking memory from pools other than the per-request one, we * allocate a module-private pool, and then use a sub-pool of that which gets * freed each time we modify the trace. That way previous layers of trace * data don't get lost. */ static apr_pool_t *x_pool = NULL; static apr_pool_t *x_subpool = NULL; /* * Declare ourselves so the configuration routines can find and know us. * We'll fill it in at the end of the module. */ module AP_MODULE_DECLARE_DATA example_module; /*--------------------------------------------------------------------------*/ /* */ /* The following pseudo-prototype declarations illustrate the parameters */ /* passed to command handlers for the different types of directive */ /* syntax. If an argument was specified in the directive definition */ /* (look for "command_rec" below), it's available to the command handler */ /* via the (void *) info field in the cmd_parms argument passed to the */ /* handler (cmd->info for the examples below). */ /* */ /*--------------------------------------------------------------------------*/ /* * Command handler for a NO_ARGS directive. Declared in the command_rec * list with * AP_INIT_NO_ARGS("directive", function, mconfig, where, help) * * static const char *handle_NO_ARGS(cmd_parms *cmd, void *mconfig); */ /* * Command handler for a RAW_ARGS directive. The "args" argument is the text * of the commandline following the directive itself. Declared in the * command_rec list with * AP_INIT_RAW_ARGS("directive", function, mconfig, where, help) * * static const char *handle_RAW_ARGS(cmd_parms *cmd, void *mconfig, * const char *args); */ /* * Command handler for a FLAG directive. The single parameter is passed in * "bool", which is either zero or not for Off or On respectively. * Declared in the command_rec list with * AP_INIT_FLAG("directive", function, mconfig, where, help) * * static const char *handle_FLAG(cmd_parms *cmd, void *mconfig, int bool); */ /* * Command handler for a TAKE1 directive. The single parameter is passed in * "word1". Declared in the command_rec list with * AP_INIT_TAKE1("directive", function, mconfig, where, help) * * static const char *handle_TAKE1(cmd_parms *cmd, void *mconfig, * char *word1); */ /* * Command handler for a TAKE2 directive. TAKE2 commands must always have * exactly two arguments. Declared in the command_rec list with * AP_INIT_TAKE2("directive", function, mconfig, where, help) * * static const char *handle_TAKE2(cmd_parms *cmd, void *mconfig, * char *word1, char *word2); */ /* * Command handler for a TAKE3 directive. Like TAKE2, these must have exactly * three arguments, or the parser complains and doesn't bother calling us. * Declared in the command_rec list with * AP_INIT_TAKE3("directive", function, mconfig, where, help) * * static const char *handle_TAKE3(cmd_parms *cmd, void *mconfig, * char *word1, char *word2, char *word3); */ /* * Command handler for a TAKE12 directive. These can take either one or two * arguments. * - word2 is a NULL pointer if no second argument was specified. * Declared in the command_rec list with * AP_INIT_TAKE12("directive", function, mconfig, where, help) * * static const char *handle_TAKE12(cmd_parms *cmd, void *mconfig, * char *word1, char *word2); */ /* * Command handler for a TAKE123 directive. A TAKE123 directive can be given, * as might be expected, one, two, or three arguments. * - word2 is a NULL pointer if no second argument was specified. * - word3 is a NULL pointer if no third argument was specified. * Declared in the command_rec list with * AP_INIT_TAKE123("directive", function, mconfig, where, help) * * static const char *handle_TAKE123(cmd_parms *cmd, void *mconfig, * char *word1, char *word2, char *word3); */ /* * Command handler for a TAKE13 directive. Either one or three arguments are * permitted - no two-parameters-only syntax is allowed. * - word2 and word3 are NULL pointers if only one argument was specified. * Declared in the command_rec list with * AP_INIT_TAKE13("directive", function, mconfig, where, help) * * static const char *handle_TAKE13(cmd_parms *cmd, void *mconfig, * char *word1, char *word2, char *word3); */ /* * Command handler for a TAKE23 directive. At least two and as many as three * arguments must be specified. * - word3 is a NULL pointer if no third argument was specified. * Declared in the command_rec list with * AP_INIT_TAKE23("directive", function, mconfig, where, help) * * static const char *handle_TAKE23(cmd_parms *cmd, void *mconfig, * char *word1, char *word2, char *word3); */ /* * Command handler for a ITERATE directive. * - Handler is called once for each of n arguments given to the directive. * - word1 points to each argument in turn. * Declared in the command_rec list with * AP_INIT_ITERATE("directive", function, mconfig, where, help) * * static const char *handle_ITERATE(cmd_parms *cmd, void *mconfig, * char *word1); */ /* * Command handler for a ITERATE2 directive. * - Handler is called once for each of the second and subsequent arguments * given to the directive. * - word1 is the same for each call for a particular directive instance (the * first argument). * - word2 points to each of the second and subsequent arguments in turn. * Declared in the command_rec list with * AP_INIT_ITERATE2("directive", function, mconfig, where, help) * * static const char *handle_ITERATE2(cmd_parms *cmd, void *mconfig, * char *word1, char *word2); */ /*--------------------------------------------------------------------------*/ /* */ /* These routines are strictly internal to this module, and support its */ /* operation. They are not referenced by any external portion of the */ /* server. */ /* */ /*--------------------------------------------------------------------------*/ /* * Locate our directory configuration record for the current request. */ static x_cfg *our_dconfig(const request_rec *r) { return (x_cfg *) ap_get_module_config(r->per_dir_config, &example_module); } #if 0 /* * Locate our server configuration record for the specified server. */ static x_cfg *our_sconfig(const server_rec *s) { return (x_cfg *) ap_get_module_config(s->module_config, &example_module); } /* * Likewise for our configuration record for the specified request. */ static x_cfg *our_rconfig(const request_rec *r) { return (x_cfg *) ap_get_module_config(r->request_config, &example_module); } #endif /* * Likewise for our configuration record for a connection. */ static x_cfg *our_cconfig(const conn_rec *c) { return (x_cfg *) ap_get_module_config(c->conn_config, &example_module); } /* * This routine sets up some module-wide cells if they haven't been already. */ static void setup_module_cells(void) { /* * If we haven't already allocated our module-private pool, do so now. */ if (x_pool == NULL) { apr_pool_create(&x_pool, NULL); }; /* * Likewise for the table of routine/environment pairs we visit outside of * request context. */ if (static_calls_made == NULL) { static_calls_made = apr_table_make(x_pool, 16); }; } /* * This routine is used to add a trace of a callback to the list. We're * passed the server record (if available), the request record (if available), * a pointer to our private configuration record (if available) for the * environment to which the callback is supposed to apply, and some text. We * turn this into a textual representation and add it to the tail of the list. * The list can be displayed by the x_handler() routine. * * If the call occurs within a request context (i.e., we're passed a request * record), we put the trace into the request apr_pool_t and attach it to the * request via the notes mechanism. Otherwise, the trace gets added * to the static (non-request-specific) list. * * Note that the r->notes table is only for storing strings; if you need to * maintain per-request data of any other type, you need to use another * mechanism. */ #define TRACE_NOTE "example-trace" static void trace_add(server_rec *s, request_rec *r, x_cfg *mconfig, const char *note) { const char *sofar; char *addon; char *where; apr_pool_t *p; const char *trace_copy; /* * Make sure our pools and tables are set up - we need 'em. */ setup_module_cells(); /* * Now, if we're in request-context, we use the request pool. */ if (r != NULL) { p = r->pool; if ((trace_copy = apr_table_get(r->notes, TRACE_NOTE)) == NULL) { trace_copy = ""; } } else { /* * We're not in request context, so the trace gets attached to our * module-wide pool. We do the create/destroy every time we're called * in non-request context; this avoids leaking memory in some of * the subsequent calls that allocate memory only once (such as the * key formation below). * * Make a new sub-pool and copy any existing trace to it. Point the * trace cell at the copied value. */ apr_pool_create(&p, x_pool); if (trace != NULL) { trace = apr_pstrdup(p, trace); } /* * Now, if we have a sub-pool from before, nuke it and replace with * the one we just allocated. */ if (x_subpool != NULL) { apr_pool_destroy(x_subpool); } x_subpool = p; trace_copy = trace; } /* * If we weren't passed a configuration record, we can't figure out to * what location this call applies. This only happens for co-routines * that don't operate in a particular directory or server context. If we * got a valid record, extract the location (directory or server) to which * it applies. */ where = (mconfig != NULL) ? mconfig->loc : "nowhere"; where = (where != NULL) ? where : ""; /* * Now, if we're not in request context, see if we've been called with * this particular combination before. The apr_table_t is allocated in the * module's private pool, which doesn't get destroyed. */ if (r == NULL) { char *key; key = apr_pstrcat(p, note, ":", where, NULL); if (apr_table_get(static_calls_made, key) != NULL) { /* * Been here, done this. */ return; } else { /* * First time for this combination of routine and environment - * log it so we don't do it again. */ apr_table_set(static_calls_made, key, "been here"); } } addon = apr_pstrcat(p, "
  • \n" "
    \n" "
    ", note, "
    \n" "
    [", where, "]
    \n" "
    \n" "
  • \n", NULL); sofar = (trace_copy == NULL) ? "" : trace_copy; trace_copy = apr_pstrcat(p, sofar, addon, NULL); if (r != NULL) { apr_table_set(r->notes, TRACE_NOTE, trace_copy); } else { trace = trace_copy; } /* * You *could* change the following if you wanted to see the calling * sequence reported in the server's error_log, but beware - almost all of * these co-routines are called for every single request, and the impact * on the size (and readability) of the error_log is considerable. */ #define EXAMPLE_LOG_EACH 0 if (EXAMPLE_LOG_EACH && (s != NULL)) { ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s, "mod_example: %s", note); } } /*--------------------------------------------------------------------------*/ /* We prototyped the various syntax for command handlers (routines that */ /* are called when the configuration parser detects a directive declared */ /* by our module) earlier. Now we actually declare a "real" routine that */ /* will be invoked by the parser when our "real" directive is */ /* encountered. */ /* */ /* If a command handler encounters a problem processing the directive, it */ /* signals this fact by returning a non-NULL pointer to a string */ /* describing the problem. */ /* */ /* The magic return value DECLINE_CMD is used to deal with directives */ /* that might be declared by multiple modules. If the command handler */ /* returns NULL, the directive was processed; if it returns DECLINE_CMD, */ /* the next module (if any) that declares the directive is given a chance */ /* at it. If it returns any other value, it's treated as the text of an */ /* error message. */ /*--------------------------------------------------------------------------*/ /* * Command handler for the NO_ARGS "Example" directive. All we do is mark the * call in the trace log, and flag the applicability of the directive to the * current location in that location's configuration record. */ static const char *cmd_example(cmd_parms *cmd, void *mconfig) { x_cfg *cfg = (x_cfg *) mconfig; /* * "Example Wuz Here" */ cfg->local = 1; trace_add(cmd->server, NULL, cfg, "cmd_example()"); return NULL; } /*--------------------------------------------------------------------------*/ /* */ /* Now we declare our content handlers, which are invoked when the server */ /* encounters a document which our module is supposed to have a chance to */ /* see. (See mod_mime's SetHandler and AddHandler directives, and the */ /* mod_info and mod_status examples, for more details.) */ /* */ /* Since content handlers are dumping data directly into the connection */ /* (using the r*() routines, such as rputs() and rprintf()) without */ /* intervention by other parts of the server, they need to make */ /* sure any accumulated HTTP headers are sent first. This is done by */ /* calling send_http_header(). Otherwise, no header will be sent at all, */ /* and the output sent to the client will actually be HTTP-uncompliant. */ /*--------------------------------------------------------------------------*/ /* * Sample content handler. All this does is display the call list that has * been built up so far. * * The return value instructs the caller concerning what happened and what to * do next: * OK ("we did our thing") * DECLINED ("this isn't something with which we want to get involved") * HTTP_mumble ("an error status should be reported") */ static int x_handler(request_rec *r) { x_cfg *dcfg; if (strcmp(r->handler, "example-handler")) { return DECLINED; } dcfg = our_dconfig(r); trace_add(r->server, r, dcfg, "x_handler()"); /* * We're about to start sending content, so we need to force the HTTP * headers to be sent at this point. Otherwise, no headers will be sent * at all. We can set any we like first, of course. **NOTE** Here's * where you set the "Content-type" header, and you do so by putting it in * r->content_type, *not* r->headers_out("Content-type"). If you don't * set it, it will be filled in with the server's default type (typically * "text/plain"). You *must* also ensure that r->content_type is lower * case. * * We also need to start a timer so the server can know if the connexion * is broken. */ ap_set_content_type(r, "text/html"); /* * If we're only supposed to send header information (HEAD request), we're * already there. */ if (r->header_only) { return OK; } /* * Now send our actual output. Since we tagged this as being * "text/html", we need to embed any HTML. */ ap_rputs(DOCTYPE_HTML_3_2, r); ap_rputs("\n", r); ap_rputs(" \n", r); ap_rputs(" mod_example Module Content-Handler Output\n", r); ap_rputs(" \n", r); ap_rputs(" \n", r); ap_rputs(" \n", r); ap_rputs("

    mod_example Module Content-Handler Output\n", r); ap_rputs("

    \n", r); ap_rputs("

    \n", r); ap_rprintf(r, " Apache HTTP Server version: \"%s\"\n", ap_get_server_version()); ap_rputs("
    \n", r); ap_rprintf(r, " Server built: \"%s\"\n", ap_get_server_built()); ap_rputs("

    \n", r);; ap_rputs("

    \n", r); ap_rputs(" The format for the callback trace is:\n", r); ap_rputs("

    \n", r); ap_rputs("
    \n", r); ap_rputs("
    n.<routine-name>", r); ap_rputs("(<routine-data>)\n", r); ap_rputs("
    \n", r); ap_rputs("
    [<applies-to>]\n", r); ap_rputs("
    \n", r); ap_rputs("
    \n", r); ap_rputs("

    \n", r); ap_rputs(" The <routine-data> is supplied by\n", r); ap_rputs(" the routine when it requests the trace,\n", r); ap_rputs(" and the <applies-to> is extracted\n", r); ap_rputs(" from the configuration record at the time of the trace.\n", r); ap_rputs(" SVR() indicates a server environment\n", r); ap_rputs(" (blank means the main or default server, otherwise it's\n", r); ap_rputs(" the name of the VirtualHost); DIR()\n", r); ap_rputs(" indicates a location in the URL or filesystem\n", r); ap_rputs(" namespace.\n", r); ap_rputs("

    \n", r); ap_rprintf(r, "

    Static callbacks so far:

    \n
      \n%s
    \n", trace); ap_rputs("

    Request-specific callbacks so far:

    \n", r); ap_rprintf(r, "
      \n%s
    \n", apr_table_get(r->notes, TRACE_NOTE)); ap_rputs("

    Environment for this call:

    \n", r); ap_rputs(" \n", r); ap_rputs(" \n", r); ap_rputs("\n", r); /* * We're all done, so cancel the timeout we set. Since this is probably * the end of the request we *could* assume this would be done during * post-processing - but it's possible that another handler might be * called and inherit our outstanding timer. Not good; to each its own. */ /* * We did what we wanted to do, so tell the rest of the server we * succeeded. */ return OK; } /*--------------------------------------------------------------------------*/ /* */ /* Now let's declare routines for each of the callback phase in order. */ /* (That's the order in which they're listed in the callback list, *not */ /* the order in which the server calls them! See the command_rec */ /* declaration near the bottom of this file.) Note that these may be */ /* called for situations that don't relate primarily to our function - in */ /* other words, the fixup handler shouldn't assume that the request has */ /* to do with "example" stuff. */ /* */ /* With the exception of the content handler, all of our routines will be */ /* called for each request, unless an earlier handler from another module */ /* aborted the sequence. */ /* */ /* Handlers that are declared as "int" can return the following: */ /* */ /* OK Handler accepted the request and did its thing with it. */ /* DECLINED Handler took no action. */ /* HTTP_mumble Handler looked at request and found it wanting. */ /* */ /* What the server does after calling a module handler depends upon the */ /* handler's return value. In all cases, if the handler returns */ /* DECLINED, the server will continue to the next module with an handler */ /* for the current phase. However, if the handler return a non-OK, */ /* non-DECLINED status, the server aborts the request right there. If */ /* the handler returns OK, the server's next action is phase-specific; */ /* see the individual handler comments below for details. */ /* */ /*--------------------------------------------------------------------------*/ /* * This function is called during server initialisation. Any information * that needs to be recorded must be in static cells, since there's no * configuration record. * * There is no return value. */ /* * This function is called when an heavy-weight process (such as a child) is * being run down or destroyed. As with the child initialisation function, * any information that needs to be recorded must be in static cells, since * there's no configuration record. * * There is no return value. */ /* * This function is called during server initialisation when an heavy-weight * process (such as a child) is being initialised. As with the * module initialisation function, any information that needs to be recorded * must be in static cells, since there's no configuration record. * * There is no return value. */ /* * This function gets called to create a per-directory configuration * record. This will be called for the "default" server environment, and for * each directory for which the parser finds any of our directives applicable. * If a directory doesn't have any of our directives involved (i.e., they * aren't in the .htaccess file, or a , , or related * block), this routine will *not* be called - the configuration for the * closest ancestor is used. * * The return value is a pointer to the created module-specific * structure. */ static void *x_create_dir_config(apr_pool_t *p, char *dirspec) { x_cfg *cfg; char *dname = dirspec; /* * Allocate the space for our record from the pool supplied. */ cfg = (x_cfg *) apr_pcalloc(p, sizeof(x_cfg)); /* * Now fill in the defaults. If there are any `parent' configuration * records, they'll get merged as part of a separate callback. */ cfg->local = 0; cfg->congenital = 0; cfg->cmode = CONFIG_MODE_DIRECTORY; /* * Finally, add our trace to the callback list. */ dname = (dname != NULL) ? dname : ""; cfg->loc = apr_pstrcat(p, "DIR(", dname, ")", NULL); trace_add(NULL, NULL, cfg, "x_create_dir_config()"); return (void *) cfg; } /* * This function gets called to merge two per-directory configuration * records. This is typically done to cope with things like .htaccess files * or directives for directories that are beneath one for which a * configuration record was already created. The routine has the * responsibility of creating a new record and merging the contents of the * other two into it appropriately. If the module doesn't declare a merge * routine, the record for the closest ancestor location (that has one) is * used exclusively. * * The routine MUST NOT modify any of its arguments! * * The return value is a pointer to the created module-specific structure * containing the merged values. */ static void *x_merge_dir_config(apr_pool_t *p, void *parent_conf, void *newloc_conf) { x_cfg *merged_config = (x_cfg *) apr_pcalloc(p, sizeof(x_cfg)); x_cfg *pconf = (x_cfg *) parent_conf; x_cfg *nconf = (x_cfg *) newloc_conf; char *note; /* * Some things get copied directly from the more-specific record, rather * than getting merged. */ merged_config->local = nconf->local; merged_config->loc = apr_pstrdup(p, nconf->loc); /* * Others, like the setting of the `congenital' flag, get ORed in. The * setting of that particular flag, for instance, is TRUE if it was ever * true anywhere in the upstream configuration. */ merged_config->congenital = (pconf->congenital | pconf->local); /* * If we're merging records for two different types of environment (server * and directory), mark the new record appropriately. Otherwise, inherit * the current value. */ merged_config->cmode = (pconf->cmode == nconf->cmode) ? pconf->cmode : CONFIG_MODE_COMBO; /* * Now just record our being called in the trace list. Include the * locations we were asked to merge. */ note = apr_pstrcat(p, "x_merge_dir_config(\"", pconf->loc, "\",\"", nconf->loc, "\")", NULL); trace_add(NULL, NULL, merged_config, note); return (void *) merged_config; } /* * This function gets called to create a per-server configuration * record. It will always be called for the "default" server. * * The return value is a pointer to the created module-specific * structure. */ static void *x_create_server_config(apr_pool_t *p, server_rec *s) { x_cfg *cfg; char *sname = s->server_hostname; /* * As with the x_create_dir_config() reoutine, we allocate and fill * in an empty record. */ cfg = (x_cfg *) apr_pcalloc(p, sizeof(x_cfg)); cfg->local = 0; cfg->congenital = 0; cfg->cmode = CONFIG_MODE_SERVER; /* * Note that we were called in the trace list. */ sname = (sname != NULL) ? sname : ""; cfg->loc = apr_pstrcat(p, "SVR(", sname, ")", NULL); trace_add(s, NULL, cfg, "x_create_server_config()"); return (void *) cfg; } /* * This function gets called to merge two per-server configuration * records. This is typically done to cope with things like virtual hosts and * the default server configuration The routine has the responsibility of * creating a new record and merging the contents of the other two into it * appropriately. If the module doesn't declare a merge routine, the more * specific existing record is used exclusively. * * The routine MUST NOT modify any of its arguments! * * The return value is a pointer to the created module-specific structure * containing the merged values. */ static void *x_merge_server_config(apr_pool_t *p, void *server1_conf, void *server2_conf) { x_cfg *merged_config = (x_cfg *) apr_pcalloc(p, sizeof(x_cfg)); x_cfg *s1conf = (x_cfg *) server1_conf; x_cfg *s2conf = (x_cfg *) server2_conf; char *note; /* * Our inheritance rules are our own, and part of our module's semantics. * Basically, just note whence we came. */ merged_config->cmode = (s1conf->cmode == s2conf->cmode) ? s1conf->cmode : CONFIG_MODE_COMBO; merged_config->local = s2conf->local; merged_config->congenital = (s1conf->congenital | s1conf->local); merged_config->loc = apr_pstrdup(p, s2conf->loc); /* * Trace our call, including what we were asked to merge. */ note = apr_pstrcat(p, "x_merge_server_config(\"", s1conf->loc, "\",\"", s2conf->loc, "\")", NULL); trace_add(NULL, NULL, merged_config, note); return (void *) merged_config; } /* * This routine is called before the server processes the configuration * files. There is no return value. */ static int x_pre_config(apr_pool_t *pconf, apr_pool_t *plog, apr_pool_t *ptemp) { /* * Log the call and exit. */ trace_add(NULL, NULL, NULL, "x_pre_config()"); return OK; } /* * This routine is called to perform any module-specific fixing of header * fields, et cetera. It is invoked just before any content-handler. * * The return value is OK, DECLINED, or HTTP_mumble. If we return OK, the * server will still call any remaining modules with an handler for this * phase. */ static int x_post_config(apr_pool_t *pconf, apr_pool_t *plog, apr_pool_t *ptemp, server_rec *s) { /* * Log the call and exit. */ trace_add(NULL, NULL, NULL, "x_post_config()"); return OK; } /* * This routine is called to perform any module-specific log file * openings. It is invoked just before the post_config phase * * The return value is OK, DECLINED, or HTTP_mumble. If we return OK, the * server will still call any remaining modules with an handler for this * phase. */ static int x_open_logs(apr_pool_t *pconf, apr_pool_t *plog, apr_pool_t *ptemp, server_rec *s) { /* * Log the call and exit. */ trace_add(s, NULL, NULL, "x_open_logs()"); return OK; } /* * All our process-death routine does is add its trace to the log. */ static apr_status_t x_child_exit(void *data) { char *note; server_rec *s = data; char *sname = s->server_hostname; /* * The arbitrary text we add to our trace entry indicates for which server * we're being called. */ sname = (sname != NULL) ? sname : ""; note = apr_pstrcat(s->process->pool, "x_child_exit(", sname, ")", NULL); trace_add(s, NULL, NULL, note); return APR_SUCCESS; } /* * All our process initialiser does is add its trace to the log. */ static void x_child_init(apr_pool_t *p, server_rec *s) { char *note; char *sname = s->server_hostname; /* * Set up any module cells that ought to be initialised. */ setup_module_cells(); /* * The arbitrary text we add to our trace entry indicates for which server * we're being called. */ sname = (sname != NULL) ? sname : ""; note = apr_pstrcat(p, "x_child_init(", sname, ")", NULL); trace_add(s, NULL, NULL, note); apr_pool_cleanup_register(p, s, x_child_exit, x_child_exit); } /* * XXX: This routine is called XXX * * The return value is OK, DECLINED, or HTTP_mumble. If we return OK, the * server will still call any remaining modules with an handler for this * phase. */ #if 0 static const char *x_http_method(const request_rec *r) { x_cfg *cfg; cfg = our_dconfig(r); /* * Log the call and exit. */ trace_add(r->server, NULL, cfg, "x_http_method()"); return "foo"; } /* * XXX: This routine is called XXX * * The return value is OK, DECLINED, or HTTP_mumble. If we return OK, the * server will still call any remaining modules with an handler for this * phase. */ static apr_port_t x_default_port(const request_rec *r) { x_cfg *cfg; cfg = our_dconfig(r); /* * Log the call and exit. */ trace_add(r->server, NULL, cfg, "x_default_port()"); return 80; } #endif /*0*/ /* * XXX: This routine is called XXX * * The return value is OK, DECLINED, or HTTP_mumble. If we return OK, the * server will still call any remaining modules with an handler for this * phase. */ static void x_insert_filter(request_rec *r) { x_cfg *cfg; cfg = our_dconfig(r); /* * Log the call and exit. */ trace_add(r->server, NULL, cfg, "x_insert_filter()"); } /* * XXX: This routine is called XXX * * The return value is OK, DECLINED, or HTTP_mumble. If we return OK, the * server will still call any remaining modules with an handler for this * phase. */ static int x_quick_handler(request_rec *r, int lookup_uri) { x_cfg *cfg; cfg = our_dconfig(r); /* * Log the call and exit. */ trace_add(r->server, NULL, cfg, "x_post_config()"); return DECLINED; } /* * This routine is called just after the server accepts the connection, * but before it is handed off to a protocol module to be served. The point * of this hook is to allow modules an opportunity to modify the connection * as soon as possible. The core server uses this phase to setup the * connection record based on the type of connection that is being used. * * The return value is OK, DECLINED, or HTTP_mumble. If we return OK, the * server will still call any remaining modules with an handler for this * phase. */ static int x_pre_connection(conn_rec *c, void *csd) { x_cfg *cfg; cfg = our_cconfig(c); #if 0 /* * Log the call and exit. */ trace_add(r->server, NULL, cfg, "x_post_config()"); #endif return OK; } /* This routine is used to actually process the connection that was received. * Only protocol modules should implement this hook, as it gives them an * opportunity to replace the standard HTTP processing with processing for * some other protocol. Both echo and POP3 modules are available as * examples. * * The return VALUE is OK, DECLINED, or HTTP_mumble. If we return OK, no * further modules are called for this phase. */ static int x_process_connection(conn_rec *c) { return DECLINED; } /* * This routine is called after the request has been read but before any other * phases have been processed. This allows us to make decisions based upon * the input header fields. * * The return value is OK, DECLINED, or HTTP_mumble. If we return OK, no * further modules are called for this phase. */ static int x_post_read_request(request_rec *r) { x_cfg *cfg; cfg = our_dconfig(r); /* * We don't actually *do* anything here, except note the fact that we were * called. */ trace_add(r->server, r, cfg, "x_post_read_request()"); return DECLINED; } /* * This routine gives our module an opportunity to translate the URI into an * actual filename. If we don't do anything special, the server's default * rules (Alias directives and the like) will continue to be followed. * * The return value is OK, DECLINED, or HTTP_mumble. If we return OK, no * further modules are called for this phase. */ static int x_translate_handler(request_rec *r) { x_cfg *cfg; cfg = our_dconfig(r); /* * We don't actually *do* anything here, except note the fact that we were * called. */ trace_add(r->server, r, cfg, "x_translate_handler()"); return DECLINED; } /* * this routine gives our module another chance to examine the request * headers and to take special action. This is the first phase whose * hooks' configuration directives can appear inside the * and similar sections, because at this stage the URI has been mapped * to the filename. For example this phase can be used to block evil * clients, while little resources were wasted on these. * * The return value is OK, DECLINED, or HTTP_mumble. If we return OK, * the server will still call any remaining modules with an handler * for this phase. */ static int x_header_parser_handler(request_rec *r) { x_cfg *cfg; cfg = our_dconfig(r); /* * We don't actually *do* anything here, except note the fact that we were * called. */ trace_add(r->server, r, cfg, "header_parser_handler()"); return DECLINED; } /* * This routine is called to check the authentication information sent with * the request (such as looking up the user in a database and verifying that * the [encrypted] password sent matches the one in the database). * * The return value is OK, DECLINED, or some HTTP_mumble error (typically * HTTP_UNAUTHORIZED). If we return OK, no other modules are given a chance * at the request during this phase. */ static int x_check_user_id(request_rec *r) { x_cfg *cfg; cfg = our_dconfig(r); /* * Don't do anything except log the call. */ trace_add(r->server, r, cfg, "x_check_user_id()"); return DECLINED; } /* * This routine is called to check to see if the resource being requested * requires authorisation. * * The return value is OK, DECLINED, or HTTP_mumble. If we return OK, no * other modules are called during this phase. * * If *all* modules return DECLINED, the request is aborted with a server * error. */ static int x_auth_checker(request_rec *r) { x_cfg *cfg; cfg = our_dconfig(r); /* * Log the call and return OK, or access will be denied (even though we * didn't actually do anything). */ trace_add(r->server, r, cfg, "x_auth_checker()"); return DECLINED; } /* * This routine is called to check for any module-specific restrictions placed * upon the requested resource. (See the mod_access module for an example.) * * The return value is OK, DECLINED, or HTTP_mumble. All modules with an * handler for this phase are called regardless of whether their predecessors * return OK or DECLINED. The first one to return any other status, however, * will abort the sequence (and the request) as usual. */ static int x_access_checker(request_rec *r) { x_cfg *cfg; cfg = our_dconfig(r); trace_add(r->server, r, cfg, "x_access_checker()"); return DECLINED; } /* * This routine is called to determine and/or set the various document type * information bits, like Content-type (via r->content_type), language, et * cetera. * * The return value is OK, DECLINED, or HTTP_mumble. If we return OK, no * further modules are given a chance at the request for this phase. */ static int x_type_checker(request_rec *r) { x_cfg *cfg; cfg = our_dconfig(r); /* * Log the call, but don't do anything else - and report truthfully that * we didn't do anything. */ trace_add(r->server, r, cfg, "x_type_checker()"); return DECLINED; } /* * This routine is called to perform any module-specific fixing of header * fields, et cetera. It is invoked just before any content-handler. * * The return value is OK, DECLINED, or HTTP_mumble. If we return OK, the * server will still call any remaining modules with an handler for this * phase. */ static int x_fixer_upper(request_rec *r) { x_cfg *cfg; cfg = our_dconfig(r); /* * Log the call and exit. */ trace_add(r->server, r, cfg, "x_fixer_upper()"); return OK; } /* * This routine is called to perform any module-specific logging activities * over and above the normal server things. * * The return value is OK, DECLINED, or HTTP_mumble. If we return OK, any * remaining modules with an handler for this phase will still be called. */ static int x_logger(request_rec *r) { x_cfg *cfg; cfg = our_dconfig(r); trace_add(r->server, r, cfg, "x_logger()"); return DECLINED; } /*--------------------------------------------------------------------------*/ /* */ /* Which functions are responsible for which hooks in the server. */ /* */ /*--------------------------------------------------------------------------*/ /* * Each function our module provides to handle a particular hook is * specified here. The functions are registered using * ap_hook_foo(name, predecessors, successors, position) * where foo is the name of the hook. * * The args are as follows: * name -> the name of the function to call. * predecessors -> a list of modules whose calls to this hook must be * invoked before this module. * successors -> a list of modules whose calls to this hook must be * invoked after this module. * position -> The relative position of this module. One of * APR_HOOK_FIRST, APR_HOOK_MIDDLE, or APR_HOOK_LAST. * Most modules will use APR_HOOK_MIDDLE. If multiple * modules use the same relative position, Apache will * determine which to call first. * If your module relies on another module to run first, * or another module running after yours, use the * predecessors and/or successors. * * The number in brackets indicates the order in which the routine is called * during request processing. Note that not all routines are necessarily * called (such as if a resource doesn't have access restrictions). * The actual delivery of content to the browser [9] is not handled by * a hook; see the handler declarations below. */ static void x_register_hooks(apr_pool_t *p) { ap_hook_pre_config(x_pre_config, NULL, NULL, APR_HOOK_MIDDLE); ap_hook_post_config(x_post_config, NULL, NULL, APR_HOOK_MIDDLE); ap_hook_open_logs(x_open_logs, NULL, NULL, APR_HOOK_MIDDLE); ap_hook_child_init(x_child_init, NULL, NULL, APR_HOOK_MIDDLE); ap_hook_handler(x_handler, NULL, NULL, APR_HOOK_MIDDLE); ap_hook_quick_handler(x_quick_handler, NULL, NULL, APR_HOOK_MIDDLE); ap_hook_pre_connection(x_pre_connection, NULL, NULL, APR_HOOK_MIDDLE); ap_hook_process_connection(x_process_connection, NULL, NULL, APR_HOOK_MIDDLE); /* [1] post read_request handling */ ap_hook_post_read_request(x_post_read_request, NULL, NULL, APR_HOOK_MIDDLE); ap_hook_log_transaction(x_logger, NULL, NULL, APR_HOOK_MIDDLE); #if 0 ap_hook_http_method(x_http_method, NULL, NULL, APR_HOOK_MIDDLE); ap_hook_default_port(x_default_port, NULL, NULL, APR_HOOK_MIDDLE); #endif ap_hook_translate_name(x_translate_handler, NULL, NULL, APR_HOOK_MIDDLE); ap_hook_header_parser(x_header_parser_handler, NULL, NULL, APR_HOOK_MIDDLE); ap_hook_check_user_id(x_check_user_id, NULL, NULL, APR_HOOK_MIDDLE); ap_hook_fixups(x_fixer_upper, NULL, NULL, APR_HOOK_MIDDLE); ap_hook_type_checker(x_type_checker, NULL, NULL, APR_HOOK_MIDDLE); ap_hook_access_checker(x_access_checker, NULL, NULL, APR_HOOK_MIDDLE); ap_hook_auth_checker(x_auth_checker, NULL, NULL, APR_HOOK_MIDDLE); ap_hook_insert_filter(x_insert_filter, NULL, NULL, APR_HOOK_MIDDLE); } /*--------------------------------------------------------------------------*/ /* */ /* All of the routines have been declared now. Here's the list of */ /* directives specific to our module, and information about where they */ /* may appear and how the command parser should pass them to us for */ /* processing. Note that care must be taken to ensure that there are NO */ /* collisions of directive names between modules. */ /* */ /*--------------------------------------------------------------------------*/ /* * List of directives specific to our module. */ static const command_rec x_cmds[] = { AP_INIT_NO_ARGS( "Example", /* directive name */ cmd_example, /* config action routine */ NULL, /* argument to include in call */ OR_OPTIONS, /* where available */ "Example directive - no arguments" /* directive description */ ), {NULL} }; /*--------------------------------------------------------------------------*/ /* */ /* Finally, the list of callback routines and data structures that provide */ /* the static hooks into our module from the other parts of the server. */ /* */ /*--------------------------------------------------------------------------*/ /* * Module definition for configuration. If a particular callback is not * needed, replace its routine name below with the word NULL. */ module AP_MODULE_DECLARE_DATA example_module = { STANDARD20_MODULE_STUFF, x_create_dir_config, /* per-directory config creator */ x_merge_dir_config, /* dir config merger */ x_create_server_config, /* server config creator */ x_merge_server_config, /* server config merger */ x_cmds, /* command table */ x_register_hooks, /* set up other request processing hooks */ };