mod_trimxml
ビルド方法
$ /usr/sbin/apxs -c mod_trimxml.c $ sudo /usr/sbin/apxs -i -A mod_trimxml.la
設定
Filter として TRIMXML を設定します。
.htaccess の設定例
# LoadModule trimxml_module modules/mod_trimxml.so
<IfModule mod_trimxml.c>
AddOutputFilterByType TRIMXML text/html
# TrimXmlUseBuiltinRule On # default: On
</IfModule>
TrimXmlUseBuiltinRule
モジュール組み込みのブラウザ判定ルーチンを使うかどうかの設定です。MSIE 2〜6 の場合にXML宣言を削除します。たいした判別ルーチンではないので期待しないでください。
デフォルトで On です。
ソース
/* mod_trimxml.c */ #include "apr_lib.h" #include "apr_strings.h" #include "ap_config.h" #include "httpd.h" #include "http_config.h" #include "http_protocol.h" #include "http_log.h" #include "http_main.h" #include "http_request.h" #include "mod_core.h" #define MATCHING_TOKEN "<?xml" #define MATCHING_TOKEN_LEN 5 module AP_MODULE_DECLARE_DATA trimxml_module; typedef struct { int use_builtin_rule; apr_array_header_t *conditional_env; } trimxml_config_rec; enum trimxml_stage_t { STAGE_START = 0, STAGE_SKIP_SPACE = STAGE_START, STAGE_WANT_TOKEN, STAGE_SKIP_TOKEN, STAGE_SKIP_CRLF, STAGE_DONE = -1 }; typedef struct { int stage; int wanted_len; apr_bucket_brigade *bb1; /* heading whitespaces */ apr_bucket_brigade *bb2; /* token for judgement */ } trimxml_ctx_t; #define APR_BUCKET_MOVE_TO_BRIGADE(e, b) \ do { \ APR_BUCKET_REMOVE((e)); \ APR_BRIGADE_INSERT_TAIL((b), (e)); \ } while (0) static int builtin_rule(request_rec *r) { const char *str; char *p; str = apr_table_get(r->headers_in, "User-Agent"); if (! str) return 0; p = strstr(str, "MSIE "); if (! p) return 0; p += 5; /* version */ if (! (*p >= '2') && (*p <= '6')) return 0; return ! strstr(str, "Opera"); } static int conditional_env_rule(request_rec *r, trimxml_config_rec *conf) { int num_envs; char **envs_ptr; if (! conf->conditional_env) return 0; envs_ptr = (char **) conf->conditional_env->elts; num_envs = conf->conditional_env->nelts; for (; num_envs > 0; envs_ptr ++, num_envs --) { char *env_ptr = *envs_ptr; const char *env_val = apr_table_get(r->subprocess_env, env_ptr); if (! env_val) continue; if (strcmp(env_val, "0")) return 1; /* anything but '0' */ } return 0; } static int xml_must_be_trimmed(request_rec *r) { trimxml_config_rec *conf = ap_get_module_config(r->per_dir_config, &trimxml_module); if (conf->use_builtin_rule) return builtin_rule(r); else return conditional_env_rule(r, conf); } static apr_status_t trimxml_filter(ap_filter_t *f, apr_bucket_brigade *bb) { request_rec *r = f->r; trimxml_ctx_t *ctx = f->ctx; if ((APR_BRIGADE_EMPTY(bb)) /* fast exit */ || (ctx && ctx->stage == STAGE_DONE)) /* already done */ return ap_pass_brigade(f->next, bb); if (! ctx) { /* initialization on the first time */ if (! xml_must_be_trimmed(r)) { ap_remove_output_filter(f); return ap_pass_brigade(f->next, bb); } else { f->ctx = ctx = apr_palloc(r->pool, sizeof(*ctx)); ctx->bb1 = apr_brigade_create(r->pool, f->c->bucket_alloc); ctx->bb2 = apr_brigade_create(r->pool, f->c->bucket_alloc); if (! ctx->bb1 || ! ctx->bb2) /** @todo: */; ctx->stage = STAGE_START; } } while (! APR_BRIGADE_EMPTY(bb)) { apr_status_t rv; apr_bucket *e; apr_size_t len; const char *str, *pos; e = APR_BRIGADE_FIRST(bb); if (APR_BUCKET_IS_EOS(e)) { switch (ctx->stage) { case STAGE_WANT_TOKEN: APR_BRIGADE_PREPEND(bb, ctx->bb2); APR_BRIGADE_PREPEND(bb, ctx->bb1); apr_brigade_destroy(ctx->bb1); apr_brigade_destroy(ctx->bb2); /* ctx->bb2 = ctx->bb1 = NULL; */ break; case STAGE_SKIP_SPACE: /* might be If-Modified-Since */ apr_brigade_destroy(ctx->bb2); /* ctx->bb2 = NULL; */ /* processing advance (prepend bb1) */ case STAGE_SKIP_TOKEN: case STAGE_SKIP_CRLF: /* Final */ APR_BRIGADE_PREPEND(bb, ctx->bb1); apr_brigade_destroy(ctx->bb1); /* ctx->bb1 = NULL; */ } ctx->stage = STAGE_DONE; return ap_pass_brigade(f->next, bb); } rv = apr_bucket_read(e, &str, &len, APR_BLOCK_READ); if (rv != APR_SUCCESS) return rv; /** @todo: */ switch (ctx->stage) { case STAGE_SKIP_SPACE: for (pos = str; len > 0; pos ++, len --) if (! apr_isspace(*pos)) break; if (len <= 0) { /* whole bucket is filled with spaces, wait next */ APR_BUCKET_MOVE_TO_BRIGADE(e, ctx->bb1); } else { apr_bucket_split(e, pos - str); APR_BUCKET_MOVE_TO_BRIGADE(e, ctx->bb1); ctx->wanted_len = MATCHING_TOKEN_LEN; ctx->stage = STAGE_WANT_TOKEN; } break; case STAGE_WANT_TOKEN: pos = str; while (len > 0 && ctx->wanted_len > 0) { pos ++, ctx->wanted_len --, len --; } if (ctx->wanted_len > 0) { /* not enough */ APR_BUCKET_MOVE_TO_BRIGADE(e, ctx->bb2); } else { char *buf; apr_bucket_split(e, pos - str); APR_BUCKET_MOVE_TO_BRIGADE(e, ctx->bb2); /* Now, make judgement */ len = MATCHING_TOKEN_LEN + 1; buf = apr_palloc(r->pool, len); if (! buf) /** @todo: */; rv = apr_brigade_flatten(ctx->bb2, buf, &len); if (rv != APR_SUCCESS) return rv; /** @todo: */ if (len < MATCHING_TOKEN_LEN || memcmp(buf, MATCHING_TOKEN, MATCHING_TOKEN_LEN)) { /* <?xml?> token doesn't exist */ /* Final */ APR_BRIGADE_PREPEND(bb, ctx->bb2); APR_BRIGADE_PREPEND(bb, ctx->bb1); apr_brigade_destroy(ctx->bb1); apr_brigade_destroy(ctx->bb2); /* ctx->bb2 = ctx->bb1 = NULL; */ ctx->stage = STAGE_DONE; return ap_pass_brigade(f->next, bb); } else { /* <?xml?> token exist */ apr_brigade_destroy(ctx->bb2); /* now useless */ /* ctx->bb2 = NULL; */ ctx->stage = STAGE_SKIP_TOKEN; } } break; case STAGE_SKIP_TOKEN: for (pos = str; len > 0; pos ++, len --) if (*pos == '>') break; if (len > 0) { apr_bucket_split(e, pos - str + 1); /* includes trail */ APR_BUCKET_REMOVE(e); /* to trash */ ctx->stage = STAGE_SKIP_CRLF; } break; case STAGE_SKIP_CRLF: for (pos = str; len > 0; pos ++, len --) if (! apr_isspace(*pos)) break; if (len > 0) { apr_bucket_split(e, pos - str); APR_BUCKET_REMOVE(e); /* to trash */ /* Final */ APR_BRIGADE_PREPEND(bb, ctx->bb1); apr_brigade_destroy(ctx->bb1); /* ctx->bb1 = NULL; */ ctx->stage = STAGE_DONE; return ap_pass_brigade(f->next, bb); } break; } } return APR_SUCCESS; } static void *create_config_rec(apr_pool_t *p, char *dummy) { trimxml_config_rec *c = apr_pcalloc(p, sizeof(trimxml_config_rec)); c->use_builtin_rule = 1; /* default: On */ c->conditional_env = NULL; return c; } static const char *add_conditonal_env(cmd_parms *cmd, void *mconfig, const char *arg) { trimxml_config_rec *c = mconfig; if (! c->conditional_env) c->conditional_env = apr_array_make(cmd->pool, 1, sizeof(char *)); *((const char **) apr_array_push(c->conditional_env)) = arg; return NULL; } static const command_rec trimxml_cmds[] = { AP_INIT_FLAG("TrimXmlUseBuiltinRule", ap_set_flag_slot, (void *) APR_OFFSETOF(trimxml_config_rec, use_builtin_rule), OR_OPTIONS, "Set to 'Off' to disable builtin browser detection mechanism. " "Use this option in conjunction with TrimXmlConditionalEnv. " "(default: On)."), AP_INIT_ITERATE("TrimXmlConditionalEnv", add_conditonal_env, NULL, OR_OPTIONS, "A list of environments for trimming <?xml?> tag. " "Only available if TrimXmlUseBuiltinRule option is set to 'Off'."), {NULL} }; static void register_hooks(apr_pool_t *p) { ap_register_output_filter("TRIMXML", trimxml_filter, NULL, AP_FTYPE_CONTENT_SET); /* after all AP_FTYPE_RESOURCE filters, and doesn't modify content-type */ } module AP_MODULE_DECLARE_DATA trimxml_module = { STANDARD20_MODULE_STUFF, create_config_rec, /* create per-directory config structure */ NULL, /* merge per-directory config structure */ NULL, /* create per-server config structure */ NULL, /* merge per-directory config structure */ trimxml_cmds, /* command apr_table_t */ register_hooks /* register hooks */ };
