From: André Malo Date: Tue, 27 May 2003 20:35:47 +0000 (+0000) Subject: [Not sure whether this will be included in 2.0.46, adjust CHANGES if necessary] X-Git-Tag: 2.0.46~8 X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=27c61911090b00996ddcc89967f875b6d59eae44;p=thirdparty%2Fapache%2Fhttpd.git [Not sure whether this will be included in 2.0.46, adjust CHANGES if necessary] Introduce "prefer-language" environment variable, which allows to influence the negotiation process on request basis to prefer a certain language, e.g.: SetEnvIf Request_URI ^/manual/foo/ prefer-language=foo Reviewed by: Jeff Trawick, Will Rowe, Erik Abele git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/APACHE_2_0_BRANCH@100045 13f79535-47bb-0310-9956-ffa450edef68 --- diff --git a/CHANGES b/CHANGES index e2d2a21aef0..cd23322203a 100644 --- a/CHANGES +++ b/CHANGES @@ -1,5 +1,9 @@ Changes with Apache 2.0.46 + *) mod_negotiation: Introduce "prefer-language" environment variable, + which allows to influence the negotiation process on request basis + to prefer a certain language. [André Malo] + *) Fix for mod_dav. Call the 'can_be_activity' callback, if provided, when a MKACTIVITY request comes in. [Ben Collins-Sussman ] diff --git a/STATUS b/STATUS index 41d63b1a37f..ffda18650e1 100644 --- a/STATUS +++ b/STATUS @@ -1,5 +1,5 @@ APACHE 2.0 STATUS: -*-text-*- -Last modified at [$Date: 2003/05/27 16:19:36 $] +Last modified at [$Date: 2003/05/27 20:35:46 $] Release: @@ -105,30 +105,6 @@ PATCHES TO PORT FROM 2.1 modules/metadata/mod_setenvif.c r1.42 +1: nd - * port the "prefer-language" env variable. - there are docs online with explanations what it does: - - - (last paragraph) - This feature would allow us to set up a resaonable (and distributable) - config for our multilingual documentation with crosslinks between the - languages, such as: - Alias /manual /path/to/manual - Alias /manual/en /path/to/manual - Alias /manual/de /path/to/manual - SetEnvIf Request_URI ^/manual/en/ prefer-language=en - SetEnvIf Request_URI ^/manual/de/ prefer-language=de - : - (but with regexps, see the backport proposal above). We're going to - get a clever system for choosing the language either by user's choice - or language negotiation. If user's choice doesn't exist, it falls back - to negotiation again. - (There's a somewhat outdated example for such cross language links: - , done with mod_rewrite, waiting for - mod_negotiation enhancement ;-)) - modules/mappers/mod_negotiation.c r1.110,r1.115 - +1: nd, trawick, wrowe - * Allow mod_dav to do weak entity comparison functions. modules/dav/main/util.c: r1.45 [ This one is under review. Don't merge. ] diff --git a/modules/mappers/mod_negotiation.c b/modules/mappers/mod_negotiation.c index 8f2670ca937..b486d6ee781 100644 --- a/modules/mappers/mod_negotiation.c +++ b/modules/mappers/mod_negotiation.c @@ -2202,74 +2202,134 @@ static int is_variant_better(negotiation_state *neg, var_rec *variant, return 1; } +/* figure out, whether a variant is in a specific language + * it returns also false, if the variant has no language. + */ +static int variant_has_language(var_rec *variant, const char *lang) +{ + int j, max; + + /* fast exit */ + if ( !lang + || !variant->content_languages + || !(max = variant->content_languages->nelts)) { + return 0; + } + + for (j = 0; j < max; ++j) { + if (!strcmp(lang, + ((char **) (variant->content_languages->elts))[j])) { + return 1; + } + } + + return 0; +} + static int best_match(negotiation_state *neg, var_rec **pbest) { int j; - var_rec *best = NULL; + var_rec *best; float bestq = 0.0f; enum algorithm_results algorithm_result; var_rec *avail_recs = (var_rec *) neg->avail_vars->elts; + const char *preferred_language = apr_table_get(neg->r->subprocess_env, + "prefer-language"); + set_default_lang_quality(neg); /* - * Find the 'best' variant + * Find the 'best' variant + * We run the loop possibly twice: if "prefer-language" + * environment variable is set but we did not find an appropriate + * best variant. In that case forget the preferred language and + * negotiate over all variants. */ - for (j = 0; j < neg->avail_vars->nelts; ++j) { - var_rec *variant = &avail_recs[j]; - - /* Find all the relevant 'quality' values from the - * Accept... headers, and store in the variant. This also - * prepares for sending an Alternates header etc so we need to - * do it even if we do not actually plan to find a best - * variant. - */ - set_accept_quality(neg, variant); - set_language_quality(neg, variant); - set_encoding_quality(neg, variant); - set_charset_quality(neg, variant); + do { + best = NULL; - /* Only do variant selection if we may actually choose a - * variant for the client - */ - if (neg->may_choose) { + for (j = 0; j < neg->avail_vars->nelts; ++j) { + var_rec *variant = &avail_recs[j]; - /* Now find out if this variant is better than the current - * best, either using the RVSA/1.0 algorithm, or Apache's - * internal server-driven algorithm. Presumably other - * server-driven algorithms are possible, and could be - * implemented here. + /* if a language is preferred, but the current variant + * is not in that language, then drop it for now */ + if ( preferred_language + && !variant_has_language(variant, preferred_language)) { + continue; + } - if (neg->use_rvsa) { - if (is_variant_better_rvsa(neg, variant, best, &bestq)) { - best = variant; - } + /* Find all the relevant 'quality' values from the + * Accept... headers, and store in the variant. This also + * prepares for sending an Alternates header etc so we need to + * do it even if we do not actually plan to find a best + * variant. + */ + set_accept_quality(neg, variant); + /* accept the preferred language, even when it's not listed within + * the Accept-Language header + */ + if (preferred_language) { + variant->lang_quality = 1.0f; + variant->definite = 1; } else { - if (is_variant_better(neg, variant, best, &bestq)) { - best = variant; + set_language_quality(neg, variant); + } + set_encoding_quality(neg, variant); + set_charset_quality(neg, variant); + + /* Only do variant selection if we may actually choose a + * variant for the client + */ + if (neg->may_choose) { + + /* Now find out if this variant is better than the current + * best, either using the RVSA/1.0 algorithm, or Apache's + * internal server-driven algorithm. Presumably other + * server-driven algorithms are possible, and could be + * implemented here. + */ + + if (neg->use_rvsa) { + if (is_variant_better_rvsa(neg, variant, best, &bestq)) { + best = variant; + } + } + else { + if (is_variant_better(neg, variant, best, &bestq)) { + best = variant; + } } } } - } - /* We now either have a best variant, or no best variant */ + /* We now either have a best variant, or no best variant */ - if (neg->use_rvsa) { - /* calculate result for RVSA/1.0 algorithm: - * only a choice response if the best variant has q>0 - * and is definite - */ - algorithm_result = (best && best->definite) && (bestq > 0) ? - alg_choice : alg_list; - } - else { - /* calculate result for Apache negotiation algorithm */ - algorithm_result = bestq > 0 ? alg_choice : alg_list; - } + if (neg->use_rvsa) { + /* calculate result for RVSA/1.0 algorithm: + * only a choice response if the best variant has q>0 + * and is definite + */ + algorithm_result = (best && best->definite) && (bestq > 0) ? + alg_choice : alg_list; + } + else { + /* calculate result for Apache negotiation algorithm */ + algorithm_result = bestq > 0 ? alg_choice : alg_list; + } + + /* run the loop again, if the "prefer-language" got no clear result */ + if (preferred_language && (!best || algorithm_result != alg_choice)) { + preferred_language = NULL; + continue; + } + + break; + } while (1); /* Returning a choice response with a non-neighboring variant is a * protocol security error in TCN (see rfc2295). We do *not*