--- /dev/null
+<?xml version="1.0"?>
+<!DOCTYPE modulesynopsis SYSTEM "../style/modulesynopsis.dtd">
+<?xml-stylesheet type="text/xsl" href="../style/manual.en.xsl"?>
+<!-- $LastChangedRevision: 966890 $ -->
+
+<!--
+ 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.
+-->
+
+<modulesynopsis metafile="mod_data.xml.meta">
+
+<name>mod_data</name>
+<description>Convert response body into an RFC2397 data URL</description>
+<status>Extension</status>
+<sourcefile>mod_data.c</sourcefile>
+<identifier>data_module</identifier>
+<compatibility>Available in Apache 2.3 and later</compatibility>
+
+<summary>
+ <p>This module provides the ability to convert a response into
+ an <a href="http://tools.ietf.org/html/rfc2397">RFC2397 data URL</a>.
+ </p>
+
+ <p>Data URLs can be embedded inline within web pages using something
+ like the <module>mod_include</module> module, to remove the need for
+ clients to make separate connections to fetch what may potentially be
+ many small images. Data URLs may also be included into pages generated
+ by scripting languages such as PHP.</p>
+
+ <example><title>An example of a data URL</title>
+ data:image/gif;base64,R0lGODdhMAAwAPAAAAAAAP///ywAAAAAMAAw<br />
+ AAAC8IyPqcvt3wCcDkiLc7C0qwyGHhSWpjQu5yqmCYsapyuvUUlvONmOZtfzgFz<br />
+ ByTB10QgxOR0TqBQejhRNzOfkVJ+5YiUqrXF5Y5lKh/DeuNcP5yLWGsEbtLiOSp<br />
+ a/TPg7JpJHxyendzWTBfX0cxOnKPjgBzi4diinWGdkF8kjdfnycQZXZeYGejmJl<br />
+ ZeGl9i2icVqaNVailT6F5iJ90m6mvuTS4OK05M0vDk0Q4XUtwvKOzrcd3iq9uis<br />
+ F81M1OIcR7lEewwcLp7tuNNkM3uNna3F2JQFo97Vriy/Xl4/f1cf5VWzXyym7PH<br />
+ hhx4dbgYKAAA7<br />
+ </example>
+
+ <p>The filter takes no parameters, and can be added to the filter stack
+ using the <directive module="core">SetOutputFilter</directive> directive,
+ or any of the directives supported by the <module>mod_filter</module>
+ module.</p>
+
+ <example><title>Configuring the filter</title>
+ <Location /data/images><br />
+ <indent>
+ SetOutputFilter DATA
+ </indent>
+ </Location><br />
+ </example>
+
+</summary>
+<seealso><a href="../filter.html">Filters</a></seealso>
+
+</modulesynopsis>
--- /dev/null
+/* 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.
+ */
+
+/*
+ * mod_data.c --- Turn the response into an rfc2397 data URL, suitable for
+ * displaying as inline content on a page.
+ */
+
+#include "apr.h"
+#include "apr_strings.h"
+#include "apr_buckets.h"
+#include "apr_base64.h"
+#include "apr_lib.h"
+
+#include "ap_config.h"
+#include "util_filter.h"
+#include "httpd.h"
+#include "http_config.h"
+#include "http_log.h"
+#include "http_request.h"
+#include "http_protocol.h"
+
+#define DATA_FILTER "DATA"
+
+module AP_MODULE_DECLARE_DATA data_module;
+
+typedef struct data_ctx
+{
+ unsigned char overflow[3];
+ int count;
+ apr_bucket_brigade *bb;
+} data_ctx;
+
+/**
+ * Create a data URL as follows:
+ *
+ * data:[<mime-type>;][charset=<charset>;]base64,<payload>
+ *
+ * Where:
+ *
+ * mime-type: The mime type of the original response.
+ * charset: The optional character set corresponding to the mime type.
+ * payload: A base64 version of the response body.
+ *
+ * The content type of the response is set to text/plain.
+ *
+ * The Content-Length header, if present, is updated with the new content
+ * length based on the increase in size expected from the base64 conversion.
+ * If the Content-Length header is too large to fit into an int, we remove
+ * the Content-Length header instead.
+ */
+static apr_status_t data_out_filter(ap_filter_t *f, apr_bucket_brigade *bb)
+{
+ apr_bucket *e;
+ request_rec *r = f->r;
+ data_ctx *ctx = f->ctx;
+ apr_status_t rv = APR_SUCCESS;
+
+ /* first time in? create a context */
+ if (!ctx) {
+ char *type;
+ char *charset;
+ char *end;
+ const char *content_length;
+
+ /* base64-ing won't work on subrequests, it would be nice if
+ * it did. Within subrequests, we have no EOS to check for,
+ * so we don't know when to flush the tail to the network.
+ */
+ if (!ap_is_initial_req(f->r)) {
+ ap_remove_output_filter(f);
+ return ap_pass_brigade(f->next, bb);
+ }
+
+ ctx = f->ctx = apr_pcalloc(r->pool, sizeof(*ctx));
+ ctx->bb = apr_brigade_create(r->pool, f->c->bucket_alloc);
+
+ type = apr_pstrdup(r->pool, r->content_type);
+ if (type) {
+ charset = strchr(type, ' ');
+ if (charset) {
+ *charset++ = 0;
+ end = strchr(charset, ' ');
+ if (end) {
+ *end++ = 0;
+ }
+ }
+ }
+
+ apr_brigade_printf(ctx->bb, NULL, NULL, "data:%s%s;base64,",
+ type ? type : "", charset ? charset : "");
+
+ content_length = apr_table_get(r->headers_out, "Content-Length");
+ if (content_length) {
+ apr_off_t len, clen;
+ apr_brigade_length(ctx->bb, 1, &len);
+ clen = apr_atoi64(content_length);
+ if (clen >= 0 && clen < APR_INT32_MAX) {
+ ap_set_content_length(r, len + apr_base64_encode_len(clen) - 1);
+ }
+ else {
+ apr_table_unset(r->headers_out, "Content-Length");
+ }
+ }
+
+ ap_set_content_type(r, "text/plain");
+
+ }
+
+ /* Do nothing if asked to filter nothing. */
+ if (APR_BRIGADE_EMPTY(bb)) {
+ return ap_pass_brigade(f->next, bb);
+ }
+
+ while (APR_SUCCESS == rv && !APR_BRIGADE_EMPTY(bb)) {
+ const char *data;
+ apr_size_t size;
+ apr_size_t tail;
+ apr_size_t len;
+ /* buffer big enough for 8000 encoded bytes (6000 raw bytes) and terminator */
+ char buffer[APR_BUCKET_BUFF_SIZE + 1];
+ char encoded[((sizeof(ctx->overflow)) / 3) * 4 + 1];
+
+ /* make sure we don't read more than 6000 bytes at a time */
+ apr_brigade_partition(bb, (APR_BUCKET_BUFF_SIZE / 4 * 3), &e);
+
+ e = APR_BRIGADE_FIRST(bb);
+
+ /* EOS means we are done. */
+ if (APR_BUCKET_IS_EOS(e)) {
+
+ /* write away the tail */
+ if (ctx->count) {
+ len = apr_base64_encode_binary(encoded, ctx->overflow,
+ ctx->count);
+ apr_brigade_write(ctx->bb, NULL, NULL, encoded, len - 1);
+ ctx->count = 0;
+ }
+
+ /* pass the EOS across */
+ APR_BUCKET_REMOVE(e);
+ APR_BRIGADE_INSERT_TAIL(ctx->bb, e);
+
+ /* pass what we have down the chain */
+ ap_remove_output_filter(f);
+ rv = ap_pass_brigade(f->next, ctx->bb);
+ continue;
+ }
+
+ /* metadata buckets are preserved as is */
+ if (APR_BUCKET_IS_METADATA(e)) {
+ /*
+ * Remove meta data bucket from old brigade and insert into the
+ * new.
+ */
+ APR_BUCKET_REMOVE(e);
+ APR_BRIGADE_INSERT_TAIL(ctx->bb, e);
+ continue;
+ }
+
+ /* size will never be more than 6000 bytes */
+ if (APR_SUCCESS == (rv = apr_bucket_read(e, &data, &size,
+ APR_BLOCK_READ))) {
+
+ /* fill up and write out our overflow buffer if partially used */
+ while (size && ctx->count && ctx->count < sizeof(ctx->overflow)) {
+ ctx->overflow[ctx->count++] = *data++;
+ size--;
+ }
+ if (ctx->count == sizeof(ctx->overflow)) {
+ len = apr_base64_encode_binary(encoded, ctx->overflow,
+ sizeof(ctx->overflow));
+ apr_brigade_write(ctx->bb, NULL, NULL, encoded, len - 1);
+ ctx->count = 0;
+ }
+
+ /* write the main base64 chunk */
+ tail = size % sizeof(ctx->overflow);
+ size -= tail;
+ if (size) {
+ len = apr_base64_encode_binary(buffer,
+ (const unsigned char *) data, size);
+ apr_brigade_write(ctx->bb, NULL, NULL, buffer, len - 1);
+ }
+
+ /* save away any tail in the overflow buffer */
+ if (tail) {
+ memcpy(ctx->overflow, data + size, tail);
+ ctx->count += tail;
+ }
+
+ apr_bucket_delete(e);
+
+ /* pass what we have down the chain */
+ rv = ap_pass_brigade(f->next, ctx->bb);
+ if (rv) {
+ /* should break out of the loop, since our write to the client
+ * failed in some way. */
+ continue;
+ }
+
+ }
+
+ }
+
+ return rv;
+
+}
+
+static const command_rec data_cmds[] = { { NULL } };
+
+static void register_hooks(apr_pool_t *p)
+{
+ ap_register_output_filter(DATA_FILTER, data_out_filter, NULL,
+ AP_FTYPE_RESOURCE);
+}
+AP_DECLARE_MODULE(data) = { STANDARD20_MODULE_STUFF,
+ NULL, /* create per-directory config structure */
+ NULL, /* merge per-directory config structures */
+ NULL, /* create per-server config structure */
+ NULL, /* merge per-server config structures */
+ data_cmds, /* command apr_table_t */
+ register_hooks /* register hooks */
+};
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