mod_include.c

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

                }

                /* See the Kludge in send_parsed_file for why */
                /* Basically, it puts a bread crumb in here, then looks */
                /*   for the crumb later to see if its been here.       */
                if (rr) 
                    ap_set_module_config(rr->request_config, 
                                         &include_module, r);

                if (!error_fmt && ap_run_sub_req(rr)) {
                    error_fmt = "unable to include \"%s\" in parsed file %s";
                }
                if (error_fmt) {
                    ap_log_rerror(APLOG_MARK, loglevel,
                                  0, r, error_fmt, tag_val, r->filename);
                    CREATE_ERROR_BUCKET(ctx, tmp_buck, head_ptr, 
                                        *inserted_head);
                }

                /* destroy the sub request */
                if (rr != NULL) {
                    ap_destroy_sub_req(rr);
                }
            }
            else {
                ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
                            "unknown parameter \"%s\" to tag include in %s",
                            tag, r->filename);
                CREATE_ERROR_BUCKET(ctx, tmp_buck, head_ptr, *inserted_head);
                return 1;
            }
        }
    }
    return 0;
}


static int handle_echo(include_ctx_t *ctx, apr_bucket_brigade **bb, 
                       request_rec *r, ap_filter_t *f, apr_bucket *head_ptr, 
                       apr_bucket **inserted_head)
{
    char       *tag       = NULL;
    char       *tag_val   = NULL;
    const char *echo_text = NULL;
    apr_bucket  *tmp_buck;
    apr_size_t e_len;
    enum {E_NONE, E_URL, E_ENTITY} encode;

    encode = E_ENTITY;

    *inserted_head = NULL;
    if (ctx->flags & FLAG_PRINTING) {
        while (1) {
            ap_ssi_get_tag_and_value(ctx, &tag, &tag_val, 1);
            if (tag_val == NULL) {
                if (tag != NULL) {
                    return 1;
                }
                else {
                    return 0;
                }
            }
            if (!strcmp(tag, "var")) {
                conn_rec *c = r->connection;
                const char *val =
                    get_include_var(r, ctx,
                                    ap_ssi_parse_string(r, ctx, tag_val, NULL,
                                                        MAX_STRING_LEN, 0));
                if (val) {
                    switch(encode) {
                    case E_NONE:   
                        echo_text = val;
                        break;
                    case E_URL:
                        echo_text = ap_escape_uri(r->pool, val);  
                        break;
                    case E_ENTITY: 
                        echo_text = ap_escape_html(r->pool, val); 
                        break;
                    }

                    e_len = strlen(echo_text);
                    tmp_buck = apr_bucket_pool_create(echo_text, e_len,
                                                      r->pool, c->bucket_alloc);
                }
                else {
                    include_server_config *sconf= 
                        ap_get_module_config(r->server->module_config,
                                             &include_module);
                    tmp_buck = apr_bucket_pool_create(sconf->undefinedEcho, 
                                                      sconf->undefinedEchoLen,
                                                      r->pool, c->bucket_alloc);
                }
                APR_BUCKET_INSERT_BEFORE(head_ptr, tmp_buck);
                if (*inserted_head == NULL) {
                    *inserted_head = tmp_buck;
                }
            }
            else if (!strcmp(tag, "encoding")) {
                if (!strcasecmp(tag_val, "none")) encode = E_NONE;
                else if (!strcasecmp(tag_val, "url")) encode = E_URL;
                else if (!strcasecmp(tag_val, "entity")) encode = E_ENTITY;
                else {
                    ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
                           "unknown value \"%s\" to parameter \"encoding\" of "
                           "tag echo in %s", tag_val, r->filename);
                    CREATE_ERROR_BUCKET(ctx, tmp_buck, head_ptr, 
                                        *inserted_head);
                    return 1;
                }
            }
            else {
                ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
                            "unknown parameter \"%s\" in tag echo of %s",
                            tag, r->filename);
                CREATE_ERROR_BUCKET(ctx, tmp_buck, head_ptr, *inserted_head);
                return 1;
            }

        }
    }
    return 0;
}

/* error and tf must point to a string with room for at 
 * least MAX_STRING_LEN characters 
 */
static int handle_config(include_ctx_t *ctx, apr_bucket_brigade **bb, 
                         request_rec *r, ap_filter_t *f, apr_bucket *head_ptr, 
                         apr_bucket **inserted_head)
{
    char *tag     = NULL;
    char *tag_val = NULL;
    char *parsed_string;
    apr_table_t *env = r->subprocess_env;

    *inserted_head = NULL;
    if (ctx->flags & FLAG_PRINTING) {
        while (1) {
            ap_ssi_get_tag_and_value(ctx, &tag, &tag_val, 0);
            if (tag_val == NULL) {
                if (tag == NULL) {
                    return 0;  /* Reached the end of the string. */
                }
                else {
                    return 1;  /* tags must have values. */
                }
            }
            if (!strcmp(tag, "errmsg")) {
                if (ctx->error_str_override == NULL) {
                    ctx->error_str_override = (char *)apr_palloc(ctx->pool,
                                                              MAX_STRING_LEN);
                    ctx->error_str = ctx->error_str_override;
                }
                ap_ssi_parse_string(r, ctx, tag_val, ctx->error_str_override,
                                    MAX_STRING_LEN, 0);
            }
            else if (!strcmp(tag, "timefmt")) {
                apr_time_t date = r->request_time;
                if (ctx->time_str_override == NULL) {
                    ctx->time_str_override = (char *)apr_palloc(ctx->pool,
                                                              MAX_STRING_LEN);
                    ctx->time_str = ctx->time_str_override;
                }
                ap_ssi_parse_string(r, ctx, tag_val, ctx->time_str_override,
                                    MAX_STRING_LEN, 0);
                apr_table_setn(env, "DATE_LOCAL", ap_ht_time(r->pool, date, 
                               ctx->time_str, 0));
                apr_table_setn(env, "DATE_GMT", ap_ht_time(r->pool, date, 
                               ctx->time_str, 1));
                apr_table_setn(env, "LAST_MODIFIED",
                               ap_ht_time(r->pool, r->finfo.mtime, 
                               ctx->time_str, 0));
            }
            else if (!strcmp(tag, "sizefmt")) {
                parsed_string = ap_ssi_parse_string(r, ctx, tag_val, NULL, 
                                                    MAX_STRING_LEN, 0);
                decodehtml(parsed_string);
                if (!strcmp(parsed_string, "bytes")) {
                    ctx->flags |= FLAG_SIZE_IN_BYTES;
                }
                else if (!strcmp(parsed_string, "abbrev")) {
                    ctx->flags &= FLAG_SIZE_ABBREV;
                }
            }
            else {
                apr_bucket *tmp_buck;

                ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
                              "unknown parameter \"%s\" to tag config in %s",
                              tag, r->filename);
                CREATE_ERROR_BUCKET(ctx, tmp_buck, head_ptr, *inserted_head);
                return 1;
            }
        }
    }
    return 0;
}


static int find_file(request_rec *r, const char *directive, const char *tag,
                     char *tag_val, apr_finfo_t *finfo)
{
    char *to_send = tag_val;
    request_rec *rr = NULL;
    int ret=0;
    char *error_fmt = NULL;
    apr_status_t rv = APR_SUCCESS;

    if (!strcmp(tag, "file")) {
        /* XXX: Port to apr_filepath_merge
         * be safe; only files in this directory or below allowed 
         */
        if (!is_only_below(tag_val)) {
            error_fmt = "unable to access file \"%s\" "
                        "in parsed file %s";
        }
        else {
            ap_getparents(tag_val);    /* get rid of any nasties */

            /* note: it is okay to pass NULL for the "next filter" since
               we never attempt to "run" this sub request. */
            rr = ap_sub_req_lookup_file(tag_val, r, NULL);

            if (rr->status == HTTP_OK && rr->finfo.filetype != 0) {
                to_send = rr->filename;
                if ((rv = apr_stat(finfo, to_send, 
                    APR_FINFO_GPROT | APR_FINFO_MIN, rr->pool)) != APR_SUCCESS
                    && rv != APR_INCOMPLETE) {
                    error_fmt = "unable to get information about \"%s\" "
                        "in parsed file %s";
                }
            }
            else {
                error_fmt = "unable to lookup information about \"%s\" "
                            "in parsed file %s";
            }
        }

        if (error_fmt) {
            ret = -1;
            ap_log_rerror(APLOG_MARK, APLOG_ERR,
                          rv, r, error_fmt, to_send, r->filename);
        }

        if (rr) ap_destroy_sub_req(rr);
        
        return ret;
    }
    else if (!strcmp(tag, "virtual")) {
        /* note: it is okay to pass NULL for the "next filter" since
           we never attempt to "run" this sub request. */
        rr = ap_sub_req_lookup_uri(tag_val, r, NULL);

        if (rr->status == HTTP_OK && rr->finfo.filetype != 0) {
            memcpy((char *) finfo, (const char *) &rr->finfo,
                   sizeof(rr->finfo));
            ap_destroy_sub_req(rr);
            return 0;
        }
        else {
            ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
                        "unable to get information about \"%s\" "
                        "in parsed file %s",
                        tag_val, r->filename);
            ap_destroy_sub_req(rr);
            return -1;
        }
    }
    else {
        ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
                    "unknown parameter \"%s\" to tag %s in %s",
                    tag, directive, r->filename);
        return -1;
    }
}

static int handle_fsize(include_ctx_t *ctx, apr_bucket_brigade **bb, 
                        request_rec *r, ap_filter_t *f, apr_bucket *head_ptr, 
                        apr_bucket **inserted_head)
{
    char *tag     = NULL;
    char *tag_val = NULL;
    apr_finfo_t  finfo;
    apr_size_t  s_len;
    apr_bucket   *tmp_buck;
    char *parsed_string;

    *inserted_head = NULL;
    if (ctx->flags & FLAG_PRINTING) {
        while (1) {
            ap_ssi_get_tag_and_value(ctx, &tag, &tag_val, 1);
            if (tag_val == NULL) {
                if (tag == NULL) {
                    return 0;
                }
                else {
                    return 1;
                }
            }
            else {
                parsed_string = ap_ssi_parse_string(r, ctx, tag_val, NULL, 
                                                    MAX_STRING_LEN, 0);
                if (!find_file(r, "fsize", tag, parsed_string, &finfo)) {
                    /* XXX: if we *know* we're going to have to copy the
                     * thing off of the stack anyway, why not palloc buff
                     * instead of sticking it on the stack; then we can just
                     * use a pool bucket and skip the copy
                     */
                    char buff[50];

                    if (!(ctx->flags & FLAG_SIZE_IN_BYTES)) {
                        apr_strfsize(finfo.size, buff);
                        s_len = strlen (buff);
                    }
                    else {
                        int l, x, pos = 0;
                        char tmp_buff[50];

                        apr_snprintf(tmp_buff, sizeof(tmp_buff), 
                                     "%" APR_OFF_T_FMT, finfo.size);
                        l = strlen(tmp_buff);    /* grrr */
                        for (x = 0; x < l; x++) {
                            if (x && (!((l - x) % 3))) {
                                buff[pos++] = ',';
                            }
                            buff[pos++] = tmp_buff[x];
                        }
                        buff[pos] = '\0';
                        s_len = pos;
                    }

                    tmp_buck = apr_bucket_heap_create(buff, s_len, NULL,
                                                  r->connection->bucket_alloc);
                    APR_BUCKET_INSERT_BEFORE(head_ptr, tmp_buck);
                    if (*inserted_head == NULL) {
                        *inserted_head = tmp_buck;
                    }
                }
                else {
                    CREATE_ERROR_BUCKET(ctx, tmp_buck, head_ptr, 
                                        *inserted_head);
                    return 1;
                }
            }
        }
    }
    return 0;
}

static int handle_flastmod(include_ctx_t *ctx, apr_bucket_brigade **bb, 
                           request_rec *r, ap_filter_t *f, 
                           apr_bucket *head_ptr, apr_bucket **inserted_head)
{
    char *tag     = NULL;
    char *tag_val = NULL;
    apr_finfo_t  finfo;
    apr_size_t  t_len;
    apr_bucket   *tmp_buck;
    char *parsed_string;

    *inserted_head = NULL;
    if (ctx->flags & FLAG_PRINTING) {
        while (1) {
            ap_ssi_get_tag_and_value(ctx, &tag, &tag_val, 1);
            if (tag_val == NULL) {
                if (tag == NULL) {
                    return 0;
                }
                else {
                    return 1;
                }
            }
            else {
                parsed_string = ap_ssi_parse_string(r, ctx, tag_val, NULL, 
                                                    MAX_STRING_LEN, 0);
                if (!find_file(r, "flastmod", tag, parsed_string, &finfo)) {
                    char *t_val;

                    t_val = ap_ht_time(r->pool, finfo.mtime, ctx->time_str, 0);
                    t_len = strlen(t_val);

                    tmp_buck = apr_bucket_pool_create(t_val, t_len, r->pool,
                                                  r->connection->bucket_alloc);
                    APR_BUCKET_INSERT_BEFORE(head_ptr, tmp_buck);
                    if (*inserted_head == NULL) {