fulltext search

2025-03-09 00:00:04 +01:00 · 2018-10-14 11:38:08 +08:00 · 2018-10-14 11:38:08 +08:00 · d3bc2c3f4f
commit d3bc2c3f4f
parent 602b0934c8
35 changed files with 35405 additions and 9 deletions
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@ -43,6 +43,7 @@ option(LWS_WITH_HTTP_STREAM_COMPRESSION "Support HTTP stream compression" OFF)
 option(LWS_WITH_HTTP_BROTLI "Also offer brotli http stream compression (requires LWS_WITH_HTTP_STREAM_COMPRESSION)" OFF)
 option(LWS_WITH_ACME "Enable support for ACME automatic cert acquisition + maintenance (letsencrypt etc)" OFF)
 option(LWS_WITH_HUBBUB "Enable libhubbub rewriting support" OFF)
+option(LWS_WITH_FTS "Full Text Search support" ON)
 #
 # TLS library options... all except mbedTLS are basically OpenSSL variants.
 #
@ -132,6 +133,7 @@ if(LWS_WITH_DISTRO_RECOMMENDED)
 	set(LWS_WITH_LIBEVENT 0)
 	set(LWS_WITHOUT_EXTENSIONS 0)
 	set(LWS_ROLE_DBUS 1)
+	set(LWS_WITH_FTS 1)
 endif()

 # do you care about this?  Then send me a patch where it disables it on travis
@ -152,6 +154,7 @@ endif()

 if (LWS_WITH_ESP32)
 	set(LWS_WITH_LWSAC 0)
+	set(LWS_WITH_FTS 0)
 endif()

 project(libwebsockets C)
@ -239,7 +242,7 @@ if (LWS_WITH_HTTP2 AND LWS_WITHOUT_SERVER)
 endif()


-include_directories(include)
+include_directories(include plugins)


 if (LWS_WITH_LWSWS)
@ -886,6 +889,12 @@ if (LWS_WITH_LWSAC)
 		lib/misc/lwsac/cached-file.c)
 endif()

+if (LWS_WITH_FTS)
+	list(APPEND SOURCES
+		lib/misc/fts/trie.c
+		lib/misc/fts/trie-fd.c)
+endif()
+
 if (NOT LWS_WITHOUT_CLIENT)
 	list(APPEND SOURCES
 		lib/core/connect.c
@ -1941,6 +1950,12 @@ endif()
 		create_plugin(protocol_post_demo ""
 			      "plugins/protocol_post_demo.c" "" "")

+if (LWS_WITH_FTS)
+		create_plugin(protocol_fulltext_demo ""
+			      "plugins/protocol_fulltext_demo.c" "" "")
+endif()
+
+
 if (LWS_WITH_SSL)
 		create_plugin(protocol_lws_ssh_base "plugins/ssh-base/include"
 			      "plugins/ssh-base/sshd.c;plugins/ssh-base/telnet.c;plugins/ssh-base/kex-25519.c" "plugins/ssh-base/crypto/chacha.c;plugins/ssh-base/crypto/ed25519.c;plugins/ssh-base/crypto/fe25519.c;plugins/ssh-base/crypto/ge25519.c;plugins/ssh-base/crypto/poly1305.c;plugins/ssh-base/crypto/sc25519.c;plugins/ssh-base/crypto/smult_curve25519_ref.c" "")
--- a/cmake/lws_config.h.in
+++ b/cmake/lws_config.h.in
@ -16,6 +16,7 @@
 #cmakedefine LWS_ROLE_DBUS

 #cmakedefine LWS_WITH_LWSAC
+#cmakedefine LWS_WITH_FTS

 /* Define to 1 to use wolfSSL/CyaSSL as a replacement for OpenSSL.
 * LWS_OPENSSL_SUPPORT needs to be set also for this to work. */
--- a/doc-assets/lws-fts.svg
+++ b/doc-assets/lws-fts.svg
@ -0,0 +1,63 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<svg width="187.45mm" height="114.8mm" version="1.1" viewBox="0 0 187.4528 114.80323" xmlns="http://www.w3.org/2000/svg">
+	<defs>
+		<marker id="b" overflow="visible" orient="auto">
+			<path transform="matrix(-.2 0 0 -.2 -1.2 0)" d="m0 0 5-5-17.5 5 17.5 5z" fill-rule="evenodd" stroke="#000" stroke-width="1pt"/>
+		</marker>
+		<marker id="c" overflow="visible" orient="auto">
+			<path transform="matrix(-.2 0 0 -.2 -1.2 0)" d="m0 0 5-5-17.5 5 17.5 5z" fill-rule="evenodd" stroke="#000" stroke-width="1pt"/>
+		</marker>
+		<marker id="a" overflow="visible" orient="auto">
+			<path transform="matrix(-.2 0 0 -.2 -1.2 0)" d="m0 0 5-5-17.5 5 17.5 5z" fill-rule="evenodd" stroke="#000" stroke-width="1pt"/>
+		</marker>
+		<marker id="d" overflow="visible" orient="auto">
+			<path transform="matrix(-.2 0 0 -.2 -1.2 0)" d="m0 0 5-5-17.5 5 17.5 5z" fill-rule="evenodd" stroke="#000" stroke-width="1pt"/>
+		</marker>
+		<marker id="f" overflow="visible" orient="auto">
+			<path transform="matrix(-.2 0 0 -.2 -1.2 0)" d="m0 0 5-5-17.5 5 17.5 5z" fill-rule="evenodd" stroke="#000" stroke-width="1pt"/>
+		</marker>
+		<marker id="e" overflow="visible" orient="auto">
+			<path transform="matrix(-.2 0 0 -.2 -1.2 0)" d="m0 0 5-5-17.5 5 17.5 5z" fill-rule="evenodd" stroke="#000" stroke-width="1pt"/>
+		</marker>
+		<marker id="g" overflow="visible" orient="auto">
+			<path transform="matrix(-.2 0 0 -.2 -1.2 0)" d="m0 0 5-5-17.5 5 17.5 5z" fill-rule="evenodd" stroke="#000" stroke-width="1pt"/>
+		</marker>
+		<filter id="h" x="-.018221" y="-.030454" width="1.0364" height="1.0609" color-interpolation-filters="sRGB">
+			<feGaussianBlur stdDeviation="1.0113078"/>
+		</filter>
+	</defs>
+	<g transform="translate(223.75 183.73)">
+		<g>
+			<rect transform="matrix(1.3577 0 0 1.3577 157.53 159.82)" x="-278.39" y="-250.61" width="133.21" height="79.7" filter="url(#h)"/>
+			<rect x="-221.47" y="-181.71" width="180.86" height="108.21" fill="#fff"/>
+			<rect x="-136.12" y="-131.41" width="66.299" height="13.971" fill="#c8c4b7"/>
+			<circle transform="rotate(-90)" cx="99.407" cy="-188.19" r="13.209" fill="#5f8dd3" opacity=".742"/>
+			<text x="-188.80128" y="-102.71894" dominant-baseline="auto" fill="#000000" font-family="'Open Sans'" font-size="5.1903px" letter-spacing="0px" stroke-width=".27805" text-align="center" text-anchor="middle" word-spacing="0px" style="font-feature-settings:normal;font-variant-alternates:normal;font-variant-caps:normal;font-variant-ligatures:normal;font-variant-numeric:normal;font-variant-position:normal;line-height:1.25;shape-padding:0;text-decoration-color:#000000;text-decoration-line:none;text-decoration-style:solid;text-indent:0;text-orientation:mixed;text-transform:none;white-space:normal" xml:space="preserve"><tspan x="-188.80128" y="-102.71894">Original</tspan><tspan x="-188.80128" y="-96.231033">Text</tspan><tspan x="-188.80128" y="-89.743126">file</tspan></text>
+			<circle transform="rotate(-90)" cx="128.11" cy="-199.63" r="13.209" fill="#5f8dd3" opacity=".742"/>
+			<text x="-199.72415" y="-131.67715" dominant-baseline="auto" fill="#000000" font-family="'Open Sans'" font-size="5.1903px" letter-spacing="0px" stroke-width=".27805" text-align="center" text-anchor="middle" word-spacing="0px" style="font-feature-settings:normal;font-variant-alternates:normal;font-variant-caps:normal;font-variant-ligatures:normal;font-variant-numeric:normal;font-variant-position:normal;line-height:1.25;shape-padding:0;text-decoration-color:#000000;text-decoration-line:none;text-decoration-style:solid;text-indent:0;text-orientation:mixed;text-transform:none;white-space:normal" xml:space="preserve"><tspan x="-199.72415" y="-131.67715">Original</tspan><tspan x="-199.72415" y="-125.18925">Text</tspan><tspan x="-199.72415" y="-118.70134">file</tspan></text>
+			<circle transform="rotate(-90)" cx="156.82" cy="-184.64" r="13.209" fill="#5f8dd3" opacity=".742"/>
+			<text x="-184.48293" y="-161.14342" dominant-baseline="auto" fill="#000000" font-family="'Open Sans'" font-size="5.1903px" letter-spacing="0px" stroke-width=".27805" text-align="center" text-anchor="middle" word-spacing="0px" style="font-feature-settings:normal;font-variant-alternates:normal;font-variant-caps:normal;font-variant-ligatures:normal;font-variant-numeric:normal;font-variant-position:normal;line-height:1.25;shape-padding:0;text-decoration-color:#000000;text-decoration-line:none;text-decoration-style:solid;text-indent:0;text-orientation:mixed;text-transform:none;white-space:normal" xml:space="preserve"><tspan x="-184.48293" y="-161.14342">Original</tspan><tspan x="-184.48293" y="-154.65552">Text</tspan><tspan x="-184.48293" y="-148.1676">file</tspan></text>
+			<circle transform="rotate(-90)" cx="126.08" cy="-154.16" r="23.116" fill="#217867"/>
+			<text x="-154.524" y="-127.70548" dominant-baseline="auto" fill="#d7f4ee" font-family="'Open Sans'" font-size="13.246px" letter-spacing="0px" stroke-width=".70963" text-align="center" text-anchor="middle" word-spacing="0px" style="font-feature-settings:normal;font-variant-alternates:normal;font-variant-caps:normal;font-variant-ligatures:normal;font-variant-numeric:normal;font-variant-position:normal;line-height:1.25;shape-padding:0;text-decoration-color:#000000;text-decoration-line:none;text-decoration-style:solid;text-indent:0;text-orientation:mixed;text-transform:none;white-space:normal" xml:space="preserve"><tspan x="-154.524" y="-127.70548">Index</tspan><tspan x="-154.524" y="-111.14747">File</tspan></text>
+		</g>
+		<g fill="none" stroke="#000" stroke-width="1.1745">
+			<path d="m-177.53-107.03c6.6045-7.3666 6.6045-7.3666 6.6045-7.3666" marker-end="url(#g)"/>
+			<path d="m-175.59-147.47 6.8585 7.3666" marker-end="url(#e)"/>
+			<path d="m-186.9-127.65 11.939 0.63506" marker-end="url(#f)"/>
+		</g>
+		<g>
+			<rect x="-113.26" y="-146.65" width="27.434" height="41.151" fill="#fca"/>
+			<text x="-99.287437" y="-128.11143" dominant-baseline="auto" fill="#000000" font-family="'Open Sans'" font-size="6.7058px" letter-spacing="0px" stroke-width=".35924" text-align="center" text-anchor="middle" word-spacing="0px" style="font-feature-settings:normal;font-variant-alternates:normal;font-variant-caps:normal;font-variant-ligatures:normal;font-variant-numeric:normal;font-variant-position:normal;line-height:1.25;shape-padding:0;text-decoration-color:#000000;text-decoration-line:none;text-decoration-style:solid;text-indent:0;text-orientation:mixed;text-transform:none;white-space:normal" xml:space="preserve"><tspan x="-99.287437" y="-128.11143">Search</tspan><tspan x="-99.287437" y="-119.72922">Action</tspan></text>
+			<text x="-83.03019" y="-161.13399" dominant-baseline="auto" fill="#000000" font-family="'Open Sans'" font-size="6.7058px" letter-spacing="0px" stroke-width=".35924" text-align="center" text-anchor="middle" word-spacing="0px" style="font-feature-settings:normal;font-variant-alternates:normal;font-variant-caps:normal;font-variant-ligatures:normal;font-variant-numeric:normal;font-variant-position:normal;line-height:1.25;shape-padding:0;text-decoration-color:#000000;text-decoration-line:none;text-decoration-style:solid;text-indent:0;text-orientation:mixed;text-transform:none;white-space:normal" xml:space="preserve"><tspan x="-83.03019" y="-161.13399" stroke-width=".35924">Keyword</tspan></text>
+			<rect x="-79.982" y="-146.91" width="27.434" height="41.151" fill="#fca"/>
+			<text x="-65.248817" y="-131.4137" dominant-baseline="auto" fill="#000000" font-family="'Open Sans'" font-size="6.7058px" letter-spacing="0px" stroke-width=".35924" text-align="center" text-anchor="middle" word-spacing="0px" style="font-feature-settings:normal;font-variant-alternates:normal;font-variant-caps:normal;font-variant-ligatures:normal;font-variant-numeric:normal;font-variant-position:normal;line-height:1.25;shape-padding:0;text-decoration-color:#000000;text-decoration-line:none;text-decoration-style:solid;text-indent:0;text-orientation:mixed;text-transform:none;white-space:normal" xml:space="preserve"><tspan x="-65.248817" y="-131.4137">Auto-</tspan><tspan x="-65.248817" y="-123.03148">comp-</tspan><tspan x="-65.248817" y="-114.64926">lete</tspan></text>
+			<text x="-82.307457" y="-85.980392" dominant-baseline="auto" fill="#000000" font-family="'Open Sans'" font-size="6.7058px" letter-spacing="0px" stroke-width=".35924" text-align="center" text-anchor="middle" word-spacing="0px" style="font-feature-settings:normal;font-variant-alternates:normal;font-variant-caps:normal;font-variant-ligatures:normal;font-variant-numeric:normal;font-variant-position:normal;line-height:1.25;shape-padding:0;text-decoration-color:#000000;text-decoration-line:none;text-decoration-style:solid;text-indent:0;text-orientation:mixed;text-transform:none;white-space:normal" xml:space="preserve"><tspan x="-82.307457" y="-85.980392" stroke-width=".35924">Result lwsac</tspan></text>
+		</g>
+		<g fill="none" stroke="#000" stroke-width="1.1745">
+			<path d="m-73.75-156.75 6.8585 7.3666" marker-end="url(#d)"/>
+			<path d="m-89.77-156.75-6.8585 7.3666" marker-end="url(#a)"/>
+			<path d="m-98.136-103.91 6.8585 7.3666" marker-end="url(#c)"/>
+			<path d="m-65.384-104.42-6.8585 7.3666" marker-end="url(#b)"/>
+		</g>
+	</g>
+</svg>
--- a/include/libwebsockets.h
+++ b/include/libwebsockets.h
@ -410,6 +410,7 @@ struct lws;
 #include <libwebsockets/lws-threadpool.h>
 #include <libwebsockets/lws-tokenize.h>
 #include <libwebsockets/lws-lwsac.h>
+#include <libwebsockets/lws-fts.h>

 #if defined(LWS_WITH_TLS)

--- a/lib/core/dummy-callback.c
+++ b/lib/core/dummy-callback.c
@ -404,7 +404,7 @@ lws_callback_http_dummy(struct lws *wsi, enum lws_callback_reasons reason,
 		buf[0] = '\0';
 		lws_get_peer_simple(parent, buf, sizeof(buf));
 		if (lws_add_http_header_by_token(wsi, WSI_TOKEN_X_FORWARDED_FOR,
-				(unsigned char *)buf, strlen(buf), p, end))
+				(unsigned char *)buf, (int)strlen(buf), p, end))
 			return -1;

 		break;
--- a/lib/core/pollfd.c
+++ b/lib/core/pollfd.c
@ -520,7 +520,7 @@ lws_callback_on_writable_all_protocol_vhost(const struct lws_vhost *vhost,
 		return -1;
 	}

-	n = protocol - vhost->protocols;
+	n = (int)(protocol - vhost->protocols);

 	lws_start_foreach_dll_safe(struct lws_dll_lws *, d, d1,
 				   vhost->same_vh_protocol_heads[n].next) {
--- a/lib/misc/fts/README.md
+++ b/lib/misc/fts/README.md
@ -0,0 +1,318 @@
+# LWS Full Text Search
+
+## Introduction
+
+![lwsac flow](/doc-assets/lws-fts.svg)
+
+The general approach is to scan one or more UTF-8 input text "files" (they may
+only exist in memory) and create an in-memory optimized trie for every token in
+the file.
+
+This can then be serialized out to disk in the form of a single index file (no
+matter how many input files were involved or how large they were).
+
+The implementation is designed to be modest on memory and cpu for both index
+creation and querying, and suitable for weak machines with some kind of random
+access storage.  For searching only memory to hold results is required, the
+actual searches and autocomplete suggestions are done very rapidly by seeking
+around structures in the on-disk index file.
+
+Function|Related Link
+---|---
+Public API|[include/libwebsockets/lws-fts.h](
+https://libwebsockets.org/git/libwebsockets/tree/include/libwebsockets/lws-fts.h)
+CI test app|[minimal-examples/api-tests/api-test-fts](https://libwebsockets.org/git/libwebsockets/tree/minimal-examples/api-tests/api-test-fts)
+Demo minimal example|[minimal-examples/http-server/minimal-http-server-fulltext-search](https://libwebsockets.org/git/libwebsockets/tree/minimal-examples/http-server/minimal-http-server-fulltext-search)
+Live Demo|[https://libwebsockets.org/ftsdemo/](https://libwebsockets.org/ftsdemo/)
+
+## Query API overview
+
+Searching returns a potentially very large lwsac allocated object, with contents
+and max size controlled by the members of a struct lws_fts_search_params passed
+to the search function.  Three kinds of result are possible:
+
+### Autocomplete suggestions
+
+These are useful to provide lists of extant results in
+realtime as the user types characters that constrain the search.  So if the
+user has typed 'len', any hits for 'len' itself are reported along with
+'length', and whatever else is in the index beginning 'len'..  The results are
+selected using and are accompanied by an aggregated count of results down that
+path, and the results so the "most likely" results already measured by potential
+hits appear first.
+ 
+These results are in a linked-list headed by `result.autocomplete_head` and
+each is in a `struct lws_fts_result_autocomplete`.
+ 
+They're enabled in the search results by giving the flag
+ `LWSFTS_F_QUERY_AUTOCOMPLETE` in the search parameter flags.
+ 
+### Filepath results 
+
+Simply a list of input files containing the search term with some statistics,
+one file is mentioned in a `struct lws_fts_result_filepath` result struct.
+
+This would be useful for creating a selection UI to "drill down" to individual
+files when there are many with matches.
+
+This is enabled by the `LWSFTS_F_QUERY_FILES` search flag.
+
+### Filepath and line results
+ 
+Same as the file path list, but for each filepath, information on the line
+numbers and input file offset where the line starts are provided.
+
+This is enabled by `LWSFTS_F_QUERY_FILE_LINES`... if you additionally give
+`LWSFTS_F_QUERY_QUOTE_LINE` flag then the contents of each hit line from the
+input file are also provided.
+ 
+## Result format inside the lwsac
+
+A `struct lws_fts_result` at the start of the lwsac contains heads for linked-
+lists of autocomplete and filepath results inside the lwsac.
+
+For autocomplete suggestions, the string itself is immediately after the
+`struct lws_fts_result_autocomplete` in memory.  For filepath results, after
+each `struct lws_fts_result_filepath` is
+
+ - match information depending on the flags given to the search
+ - the filepath string
+ 
+You can always skip the line number table to get the filepath string by adding
+.matches_length to the address of the byte after the struct.
+
+The matches information is either
+
+ - 0 bytes per match
+ 
+ - 2x int32_t per match (8 bytes) if `LWSFTS_F_QUERY_FILE_LINES` given... the
+   first is the native-endian line number of the match, the second is the
+   byte offset in the original file where that line starts
+
+ - 2 x int32_t as above plus a const char * if `LWSFTS_F_QUERY_QUOTE_LINE` is
+   also given... this points to a NUL terminated string also stored in the
+   results lwsac that contains up to 255 chars of the line from the original
+   file.  In some cases, the original file was either virtual (you are indexing
+   a git revision) or is not stored with the index, in that case you can't
+   usefully use `LWSFTS_F_QUERY_QUOTE_LINE`.
+
+To facilitate interpreting what is stored per match, the original search flags
+that created the result are stored in the `struct lws_fts_result`.
+
+## Indexing In-memory and serialized to file
+
+When creating the trie, in-memory structs are used with various optimization
+schemes trading off memory usage for speed.  While in-memory, it's possible to
+add more indexed filepaths to the single index.  Once the trie is complete in
+terms of having indexed everything, it is serialized to disk.
+
+These contain many additional housekeeping pointers and trie entries which can
+be optimized out.  Most in-memory values must be held literally in large types,
+whereas most of the values in the serialized file use smaller VLI which use
+more or less bytes according to the value.  So the peak memory requirements for
+large tries are much bigger than the size of the serialized trie file that is
+output.
+
+For the linux kernel at 4.14 and default indexing whitelist on a 2.8GHz AMD
+threadripper (using one thread), the stats are:
+
+Name|Value
+---|---
+Files indexed|52932
+Input corpus size|694MiB
+Indexing cpu time|50.1s (>1000 files / sec; 13.8MBytes/sec)
+Peak alloc|78MiB
+Serialization time|202ms
+Trie File size|347MiB
+
+To index libwebsockets master under the same conditions:
+
+Name|Value
+---|---
+Files indexed|489
+Input corpus size|3MiB
+Indexing time|123ms
+Peak alloc|3MiB
+Serialization time|1ms
+Trie File size|1.4MiB
+ 
+So the peak memory requirement to generate the whole trie in memory for that
+first is around 4x the size of the final output file.
+
+Once it's generated, querying the trie file is very inexpensive, even when there
+are lots of results.
+
+ - trie entry child lists are kept sorted by the character they map to.  This
+   allows discovering there is no match as soon as a character later in the
+   order than the one being matched is seen
+   
+ - for the root trie, in addition to the linked-list child + sibling entries,
+   a 256-entry pointer table is associated with the root trie, allowing one-
+   step lookup.  But as the table is 2KiB, it's too expensive to use on all
+   trie entries
+
+## Structure on disk
+
+All explicit multibyte numbers are stored in Network (MSB-first) byte order.
+
+ - file header
+ - filepath line number tables
+ - filepath information
+ - filepath map table
+ - tries, trie instances (hits), trie child tables
+
+### VLI coding
+
+VLI (Variable Length Integer) coding works like this
+
+[b7 EON] [b6 .. b0  DATA]
+
+If EON = 0, then DATA represents the Least-significant 7 bits of the number.
+if EON = 1, DATA represents More-significant 7-bits that should be shifted
+left until the byte with EON = 0 is found to terminate the number.
+
+The VLI used is predicated around 32-bit unsigned integers
+
+Examples:
+
+ - 0x30            =    48
+ - 0x81 30         =   176
+ - 0x81 0x80 0x00  = 16384
+
+Bytes | Range
+---|---
+1|<= 127
+2|<= 16K - 1
+3|<= 2M -1
+4|<= 256M - 1
+5|<= 4G - 1
+
+The coding is very efficient if there's a high probabilty the number being
+stored is not large.  So it's great for line numbers for example, where most
+files have less that 16K lines and the VLI for the line number fits in 2 bytes,
+but if you meet a huge file, the VLI coding can also handle it.
+
+All numbers except a few in the headers that are actually written after the
+following data are stored using VLI for space- efficiency without limiting
+capability.  The numbers that are fixed up after the fact have to have a fixed
+size and can't use VLI.
+
+### File header
+
+The first byte of the file header where the magic is, is "fileoffset" 0.  All
+the stored "fileoffset"s are relative to that.
+
+The header has a fixed size of 16 bytes.
+
+size|function
+---|---
+32-bits|Magic 0xCA7A5F75
+32-bits|Fileoffset to root trie entry
+32-bits|Size of the trie file when it was created (to detect truncation)
+32-bits|Fileoffset to the filepath map
+32-bits|Number of filepaths
+
+### Filepath line tables
+
+Immediately after the file header are the line length tables.
+
+As the input files are parsed, line length tables are written for each file...
+at that time the rest of the parser data is held in memory so nothing else is
+in the file yet.  These allow you to map logical line numbers in the file to
+file offsets space- and time- efficiently without having to walk through the
+file contents.
+
+The line information is cut into blocks, allowing quick skipping over the VLI
+data that doesn't contain the line you want just by following the 8-byte header
+part.
+
+Once you find the block with your line, you have to iteratively add the VLIs
+until you hit the one you want.
+
+For normal text files with average line length below 128, the VLIs will
+typically be a single byte.  So a block of 200 line lengths is typically
+208 bytes long.
+
+There is a final linetable chunk consisting of all zeros to indicate the end
+of the filepath line chunk series for a filepath.
+
+size|function
+---|---
+16-bit|length of this chunk itself in bytes
+16-bit|count of lines covered in this chunk
+32-bit|count of bytes in the input file this chunk covers 
+VLI...|for each line in the chunk, the number of bytes in the line
+
+
+### Filepaths
+
+The single trie in the file may contain information from multiple files, for
+example one trie may cover all files in a directory.  The "Filepaths" are
+listed after the line tables, and referred to by index thereafter.
+
+For each filepath, one after the other:
+
+size|function
+---|---
+VLI|fileoffset of the start of this filepath's line table
+VLI|count of lines in the file
+VLI|length of filepath in bytes
+...|the filepath (with no NUL)
+
+### Filepath map
+
+To facilitate rapid filepath lookup, there's a filepath map table with a 32-bit
+fileoffset per filepath.  This is the way to convert filepath indexes to
+information on the filepath like its name, etc
+
+size|function
+---|---
+32-bit...|fileoffset to filepath table for each filepath
+
+### Trie entries
+
+Immediately after that, the trie entries are dumped, for each one a header:
+
+#### Trie entry header
+
+size|function
+---|---
+VLI|Fileoffset of first file table in this trie entry instance list
+VLI|number of child trie entries this trie entry has
+VLI|number of instances this trie entry has
+
+The child list follows immediately after this header
+
+#### Trie entry instance file
+
+For each file that has instances of this symbol:
+
+size|function
+---|---
+VLI|Fileoffset of next file table in this trie entry instance list
+VLI|filepath index
+VLI|count of line number instances following
+
+#### Trie entry file line number table
+
+Then for the file mentioned above, a list of all line numbers in the file with
+the symbol in them, in ascending order.  As a VLI, the median size per entry
+will typically be ~15.9 bits due to the probability of line numbers below 16K.
+
+size|function
+---|---
+VLI|line number
+...
+
+#### Trie entry child table
+
+For each child node
+
+size|function
+---|---
+VLI|file offset of child
+VLI|instance count belonging directly to this child
+VLI|aggregated number of instances down all descendent paths of child
+VLI|aggregated number of children down all descendent paths of child
+VLI|match string length
+...|the match string
--- a/lib/misc/fts/private.h
+++ b/lib/misc/fts/private.h
@ -0,0 +1,23 @@
+#include <libwebsockets.h>
+
+/* if you need > 2GB trie files */
+//typedef off_t jg2_file_offset;
+typedef uint32_t jg2_file_offset;
+
+struct lws_fts_file {
+	int fd;
+	jg2_file_offset root, flen, filepath_table;
+	int max_direct_hits;
+	int max_completion_hits;
+	int filepaths;
+};
+
+
+
+#define TRIE_FILE_HDR_SIZE 20
+#define MAX_VLI 5
+
+#define LWS_FTS_LINES_PER_CHUNK 200
+
+int
+rq32(unsigned char *b, uint32_t *d);
--- a/lib/misc/fts/trie.c
+++ b/lib/misc/fts/trie.c
--- a/lib/plat/unix/unix-misc.c
+++ b/lib/plat/unix/unix-misc.c
@ -69,7 +69,8 @@ lws_plat_write_cert(struct lws_vhost *vhost, int is_key, int fd, void *buf,
 	n = write(fd, buf, len);

 	fsync(fd);
-	lseek(fd, 0, SEEK_SET);
+	if (lseek(fd, 0, SEEK_SET) < 0)
+		return 1;

 	return n != len;
 }
--- a/lib/roles/http/server/server.c
+++ b/lib/roles/http/server/server.c
@ -1233,9 +1233,9 @@ lws_http_action(struct lws *wsi)
 				pcolon = NULL;

 			if (pcolon)
-				n = pcolon - hit->origin;
+				n = (int)(pcolon - hit->origin);
 			else
-				n = pslash - hit->origin;
+				n = (int)(pslash - hit->origin);

 			if (n >= (int)sizeof(ads) - 2)
 				n = sizeof(ads) - 2;
@ -1270,7 +1270,8 @@ lws_http_action(struct lws *wsi)
 			}

 			*p++ = '?';
-			lws_hdr_copy(wsi, p, &rpath[sizeof(rpath) - 1] - p,
+			lws_hdr_copy(wsi, p,
+				     (int)(&rpath[sizeof(rpath) - 1] - p),
 				     WSI_TOKEN_HTTP_URI_ARGS);
 			while (--na) {
 				if (*p == '\0')
--- a/minimal-examples/api-tests/api-test-fts/CMakeLists.txt
+++ b/minimal-examples/api-tests/api-test-fts/CMakeLists.txt
@ -0,0 +1,76 @@
+cmake_minimum_required(VERSION 2.8)
+include(CheckCSourceCompiles)
+
+set(SAMP lws-api-test-fts)
+set(SRCS main.c)
+
+# If we are being built as part of lws, confirm current build config supports
+# reqconfig, else skip building ourselves.
+#
+# If we are being built externally, confirm installed lws was configured to
+# support reqconfig, else error out with a helpful message about the problem.
+#
+MACRO(require_lws_config reqconfig _val result)
+
+	if (DEFINED ${reqconfig})
+	if (${reqconfig})
+		set (rq 1)
+	else()
+		set (rq 0)
+	endif()
+	else()
+		set(rq 0)
+	endif()
+
+	if (${_val} EQUAL ${rq})
+		set(SAME 1)
+	else()
+		set(SAME 0)
+	endif()
+
+	if (LWS_WITH_MINIMAL_EXAMPLES AND NOT ${SAME})
+		if (${_val})
+			message("${SAMP}: skipping as lws being built without ${reqconfig}")
+		else()
+			message("${SAMP}: skipping as lws built with ${reqconfig}")
+		endif()
+		set(${result} 0)
+	else()
+		if (LWS_WITH_MINIMAL_EXAMPLES)
+			set(MET ${SAME})
+		else()
+			CHECK_C_SOURCE_COMPILES("#include <libwebsockets.h>\nint main(void) {\n#if defined(${reqconfig})\n return 0;\n#else\n fail;\n#endif\n return 0;\n}\n" HAS_${reqconfig})
+			if (NOT DEFINED HAS_${reqconfig} OR NOT HAS_${reqconfig})
+				set(HAS_${reqconfig} 0)
+			else()
+				set(HAS_${reqconfig} 1)
+			endif()
+			if ((HAS_${reqconfig} AND ${_val}) OR (NOT HAS_${reqconfig} AND NOT ${_val}))
+				set(MET 1)
+			else()
+				set(MET 0)
+			endif()
+		endif()
+		if (NOT MET)
+			if (${_val})
+				message(FATAL_ERROR "This project requires lws must have been configured with ${reqconfig}")
+			else()
+				message(FATAL_ERROR "Lws configuration of ${reqconfig} is incompatible with this project")
+			endif()
+		endif()
+	endif()
+ENDMACRO()
+
+set(requirements 1)
+require_lws_config(LWS_WITH_FTS 1 requirements)
+
+if (requirements)
+	add_executable(${SAMP} ${SRCS})
+
+	if (websockets_shared)
+		target_link_libraries(${SAMP} websockets_shared)
+		add_dependencies(${SAMP} websockets_shared)
+	else()
+		target_link_libraries(${SAMP} websockets)
+	endif()
+endif()
--- a/minimal-examples/api-tests/api-test-fts/README.md
+++ b/minimal-examples/api-tests/api-test-fts/README.md
@ -0,0 +1,53 @@
+# lws api test fts
+
+Demonstrates how to create indexes and perform full-text searches.
+
+## build
+
+```
+ $ cmake . && make
+```
+
+## usage
+
+Commandline option|Meaning
+---|---
+-d <loglevel>|Debug verbosity in decimal, eg, -d15
+-c / --createindex|Create an index file, instead of searching
+-i / --index <file>|Use this file as the index
+
+The two modes are:
+
+ - create an index: `--createindex inputfile [inputfile...]`
+
+```
+ $ ./lws-api-test-fts -c ./the-picture-of-dorian-gray.txt
+[2018/10/15 07:14:15:1175] USER: LWS API selftest: full-text search
+[2018/10/15 07:14:15:1531] NOTICE: lws_fts_serialize: index 1 files (0MiB) cpu time 32ms, alloc: 1024KiB + 1024KiB, serialize: 3ms, file: 325KiB 
+```
+
+ - perform search[es]: `searchterm [searchterm...]`
+
+```
+ $ ./lws-api-test-fts b
+[2018/10/15 07:15:44:1442] USER: LWS API selftest: full-text search 
+[2018/10/15 07:15:44:1442] NOTICE: lws_fts_search: 'b' Matched: 3 instances, 8 children, 0ms
+[2018/10/15 07:15:44:1443] NOTICE: lws_fts_results_dump: AC b: 3 agg hits
+[2018/10/15 07:15:44:1443] NOTICE: lws_fts_results_dump: AC be: 472 agg hits
+[2018/10/15 07:15:44:1443] NOTICE: lws_fts_results_dump: AC bee: 3 agg hits
+[2018/10/15 07:15:44:1443] NOTICE: lws_fts_results_dump: AC been: 236 agg hits
+[2018/10/15 07:15:44:1443] NOTICE: lws_fts_results_dump: AC beaut: 1 agg hits
+[2018/10/15 07:15:44:1443] NOTICE: lws_fts_results_dump: AC beauty: 55 agg hits
+[2018/10/15 07:15:44:1443] NOTICE: lws_fts_results_dump: AC because: 40 agg hits
+[2018/10/15 07:15:44:1443] NOTICE: lws_fts_results_dump: AC believe: 49 agg hits
+[2018/10/15 07:15:44:1443] NOTICE: lws_fts_results_dump: AC better: 54 agg hits
+[2018/10/15 07:15:44:1443] NOTICE: lws_fts_results_dump: AC before: 75 agg hits
+[2018/10/15 07:15:44:1443] NOTICE: lws_fts_results_dump: AC beg: 5 agg hits
+[2018/10/15 07:15:44:1443] NOTICE: lws_fts_results_dump: AC began: 44 agg hits
+[2018/10/15 07:15:44:1443] NOTICE: lws_fts_results_dump: AC but: 401 agg hits
+[2018/10/15 07:15:44:1443] NOTICE: lws_fts_results_dump: AC basil: 158 agg hits
+[2018/10/15 07:15:44:1443] NOTICE: lws_fts_results_dump: AC broke: 22 agg hits
+[2018/10/15 07:15:44:1444] NOTICE: lws_fts_results_dump: AC by: 242 agg hits
+[2018/10/15 07:15:44:1444] NOTICE: lws_fts_results_dump: AC boy: 36 agg hits
+```
+
--- a/minimal-examples/api-tests/api-test-fts/canned-1.txt
+++ b/minimal-examples/api-tests/api-test-fts/canned-1.txt
@ -0,0 +1,26 @@
+API selftest: full-text search
+AC be: 472 agg hits
+AC but: 401 agg hits
+AC by: 242 agg hits
+AC been: 236 agg hits
+AC basil: 158 agg hits
+AC before: 75 agg hits
+AC beauty: 55 agg hits
+AC better: 54 agg hits
+AC believe: 49 agg hits
+AC began: 44 agg hits
+AC because: 40 agg hits
+AC boy: 36 agg hits
+AC book: 31 agg hits
+AC body: 28 agg hits
+AC both: 26 agg hits
+AC broke: 22 agg hits
+AC beg: 5 agg hits
+AC bore: 5 agg hits
+AC b: 3 agg hits
+AC bee: 3 agg hits
+AC beaut: 1 agg hits
+no filepath results
+
+
+
--- a/minimal-examples/api-tests/api-test-fts/canned-2.txt
+++ b/minimal-examples/api-tests/api-test-fts/canned-2.txt
@ -0,0 +1,42 @@
+API selftest: full-text search
+no autocomplete results
+../minimal-examples/api-tests/api-test-fts/the-picture-of-dorian-gray.txt: (8904 lines) 32 hits 
+360
+17482
+393
+18984
+562
+28820
+837
+42903
+1640
+82057
+2037
+102214
+2091
+105019
+2145
+107351
+2725
+137188
+2808
+141127
+2977
+149971
+3429
+173810
+4417
+229186
+4431
+230058
+4656
+241181
+4708
+244372
+../minimal-examples/api-tests/api-test-fts/les-mis-utf8.txt: (14399 lines) 3 hits 
+14106
+14313
+14396
+
+
+
--- a/minimal-examples/api-tests/api-test-fts/les-mis-utf8.txt
+++ b/minimal-examples/api-tests/api-test-fts/les-mis-utf8.txt
--- a/minimal-examples/api-tests/api-test-fts/main.c
+++ b/minimal-examples/api-tests/api-test-fts/main.c
@ -0,0 +1,222 @@
+/*
+ * lws-api-test-fts
+ *
+ * Copyright (C) 2018 Andy Green <andy@warmcat.com>
+ *
+ * This file is made available under the Creative Commons CC0 1.0
+ * Universal Public Domain Dedication.
+ */
+
+#include <libwebsockets.h>
+#include <getopt.h>
+#include <fcntl.h>
+
+static struct option options[] = {
+	{ "help",	no_argument,		NULL, 'h' },
+	{ "createindex", no_argument,		NULL, 'c' },
+	{ "index",	required_argument,	NULL, 'i' },
+	{ "debug",	required_argument,	NULL, 'd' },
+	{ "file",	required_argument,	NULL, 'f' },
+	{ "lines",	required_argument,	NULL, 'l' },
+	{ NULL, 0, 0, 0 }
+};
+
+static const char *index_filepath = "/tmp/lws-fts-test-index";
+static char filepath[256];
+
+int main(int argc, char **argv)
+{
+	int n, logs = LLL_USER | LLL_ERR | LLL_WARN | LLL_NOTICE;
+	int fd, fi, ft, createindex = 0, flags = LWSFTS_F_QUERY_AUTOCOMPLETE;
+	struct lws_fts_search_params params;
+	struct lws_fts_result *result;
+	struct lws_fts_file *jtf;
+	struct lws_fts *t;
+	char buf[16384];
+
+	do {
+		n = getopt_long(argc, argv, "hd:i:cfl", options, NULL);
+		if (n < 0)
+			continue;
+		switch (n) {
+		case 'i':
+			strncpy(filepath, optarg, sizeof(filepath) - 1);
+			filepath[sizeof(filepath) - 1] = '\0';
+			index_filepath = filepath;
+			break;
+		case 'd':
+			logs = atoi(optarg);
+			break;
+		case 'c':
+			createindex = 1;
+			break;
+		case 'f':
+			flags &= ~LWSFTS_F_QUERY_AUTOCOMPLETE;
+			flags |= LWSFTS_F_QUERY_FILES;
+			break;
+		case 'l':
+			flags |= LWSFTS_F_QUERY_FILES |
+				 LWSFTS_F_QUERY_FILE_LINES;
+			break;
+		case 'h':
+			fprintf(stderr,
+				"Usage: %s [--createindex]"
+					"[--index=<index filepath>] "
+					"[-d <log bitfield>] file1 file2 \n",
+					argv[0]);
+			exit(1);
+		}
+	} while (n >= 0);
+
+	lws_set_log_level(logs, NULL);
+	lwsl_user("LWS API selftest: full-text search\n");
+
+	if (createindex) {
+
+		lwsl_notice("Creating index\n");
+
+		/*
+		 * create an index by shifting through argv and indexing each
+		 * file given there into a single combined index
+		 */
+
+		ft = open(index_filepath, O_CREAT | O_WRONLY | O_TRUNC, 0600);
+		if (ft < 0) {
+			lwsl_err("%s: can't open index %s\n", __func__,
+				 index_filepath);
+
+			goto bail;
+		}
+
+		t = lws_fts_create(ft);
+		if (!t) {
+			lwsl_err("%s: Unable to allocate trie\n", __func__);
+
+			goto bail1;
+		}
+
+		while (optind < argc) {
+
+			fi = lws_fts_file_index(t, argv[optind],
+						strlen(argv[optind]), 1);
+			if (fi < 0) {
+				lwsl_err("%s: Failed to get file idx for %s\n",
+					 __func__, argv[optind]);
+
+				goto bail1;
+			}
+
+			fd = open(argv[optind], O_RDONLY);
+			if (fd < 0) {
+				lwsl_err("unable to open %s for read\n",
+						argv[optind]);
+				goto bail;
+			}
+
+			do {
+				int n = read(fd, buf, sizeof(buf));
+
+				if (n <= 0)
+					break;
+
+				if (lws_fts_fill(t, fi, buf, n)) {
+					lwsl_err("%s: lws_fts_fill failed\n",
+						 __func__);
+					close(fd);
+
+					goto bail;
+				}
+
+			} while (1);
+
+			close(fd);
+			optind++;
+		}
+
+		if (lws_fts_serialize(t)) {
+			lwsl_err("%s: serialize failed\n", __func__);
+
+			goto bail;
+		}
+
+		lws_fts_destroy(&t);
+		close(ft);
+
+		return 0;
+	}
+
+	/*
+	 * shift through argv searching for each token
+	 */
+
+	jtf = lws_fts_open(index_filepath);
+	if (!jtf)
+		goto bail;
+
+	while (optind < argc) {
+
+		struct lws_fts_result_autocomplete *ac;
+		struct lws_fts_result_filepath *fp;
+		uint32_t *l, n;
+
+		memset(&params, 0, sizeof(params));
+
+		params.needle = argv[optind];
+		params.flags = flags;
+		params.max_autocomplete = 20;
+		params.max_files = 20;
+
+		result = lws_fts_search(jtf, &params);
+
+		if (!result) {
+			lwsl_err("%s: search failed\n", __func__);
+			lws_fts_close(jtf);
+			goto bail;
+		}
+
+		ac = result->autocomplete_head;
+		fp = result->filepath_head;
+
+		if (!ac)
+			lwsl_notice("%s: no autocomplete results\n", __func__);
+
+		while (ac) {
+			lwsl_notice("%s: AC %s: %d agg hits\n", __func__,
+				((char *)(ac + 1)), ac->instances);
+
+			ac = ac->next;
+		}
+
+		if (!fp)
+			lwsl_notice("%s: no filepath results\n", __func__);
+
+		while (fp) {
+			lwsl_notice("%s: %s: (%d lines) %d hits \n", __func__,
+				(((char *)(fp + 1)) + fp->matches_length),
+				fp->lines_in_file, fp->matches);
+
+			if (fp->matches_length) {
+				l = (uint32_t *)(fp + 1);
+				n = 0;
+				while ((int)n++ < fp->matches)
+					lwsl_notice(" %d\n", *l++);
+			}
+			fp = fp->next;
+		}
+
+		lwsac_free(&params.results_head);
+
+		optind++;
+	}
+
+	lws_fts_close(jtf);
+
+	return 0;
+
+bail1:
+	close(ft);
+bail:
+	lwsl_user("FAILED\n");
+
+	return 1;
+}
--- a/minimal-examples/api-tests/api-test-fts/selftest.sh
+++ b/minimal-examples/api-tests/api-test-fts/selftest.sh
@ -0,0 +1,58 @@
+#!/bin/bash
+#
+# $1: path to minimal example binaries...
+#     if lws is built with -DLWS_WITH_MINIMAL_EXAMPLES=1
+#     that will be ./bin from your build dir
+#
+# $2: path for logs and results.  The results will go
+#     in a subdir named after the directory this script
+#     is in
+#
+# $3: offset for test index count
+#
+# $4: total test count
+#
+# $5: path to ./minimal-examples dir in lws
+#
+# Test return code 0: OK, 254: timed out, other: error indication
+
+. $5/selftests-library.sh
+
+COUNT_TESTS=4
+
+FAILS=0
+
+#
+# let's make an index with just Dorian first
+#
+dotest $1 $2 apitest -c -i /tmp/lws-fts-dorian.index \
+    "../minimal-examples/api-tests/api-test-fts/the-picture-of-dorian-gray.txt"
+
+# and let's hear about autocompletes for "b"
+
+dotest $1 $2 apitest -i /tmp/lws-fts-dorian.index b
+cat $2/api-test-fts/apitest.log | cut -d' ' -f5- > /tmp/fts1
+diff -urN /tmp/fts1 "../minimal-examples/api-tests/api-test-fts/canned-1.txt"
+if [ $? -ne 0 ] ; then
+	echo "Test 1 failed"
+	FAILS=$(( $FAILS + 1 ))
+fi
+
+#
+# let's make an index with Dorian + Les Mis in French (ie, UTF-8) as well
+#
+dotest $1 $2 apitest -c -i /tmp/lws-fts-both.index \
+   "../minimal-examples/api-tests/api-test-fts/the-picture-of-dorian-gray.txt" \
+   "../minimal-examples/api-tests/api-test-fts/les-mis-utf8.txt"
+
+# and let's hear about "help", which appears in both
+
+dotest $1 $2 apitest -i /tmp/lws-fts-both.index -f -l help
+cat $2/api-test-fts/apitest.log | cut -d' ' -f5- > /tmp/fts2
+diff -urN /tmp/fts2 "../minimal-examples/api-tests/api-test-fts/canned-2.txt"
+if [ $? -ne 0 ] ; then
+	echo "Test 1 failed"
+	FAILS=$(( $FAILS + 1 ))
+fi
+
+exit $FAILS
--- a/minimal-examples/api-tests/api-test-fts/the-picture-of-dorian-gray.txt
+++ b/minimal-examples/api-tests/api-test-fts/the-picture-of-dorian-gray.txt
--- a/minimal-examples/http-server/README.md
+++ b/minimal-examples/http-server/README.md
@ -8,6 +8,7 @@ minimal-http-server-eventlib|Same as minimal-http-server but works with a suppor
 minimal-http-server-form-get|Process a GET form
 minimal-http-server-form-post-file|Process a multipart POST form with file transfer
 minimal-http-server-form-post|Process a POST form (no file transfer)
+minimal-http-server-fulltext-search|Demonstrates using lws Fulltext Search
 minimal-http-server-mimetypes|Shows how to add support for additional mimetypes at runtime
 minimal-http-server-multivhost|Same as minimal-http-server but three different vhosts
 minimal-http-server-proxy|Reverse Proxy
--- a/minimal-examples/http-server/minimal-http-server-fulltext-search/CMakeLists.txt
+++ b/minimal-examples/http-server/minimal-http-server-fulltext-search/CMakeLists.txt
@ -0,0 +1,81 @@
+cmake_minimum_required(VERSION 2.8)
+include(CheckCSourceCompiles)
+
+set(SAMP lws-minimal-http-server-fulltext-search)
+set(SRCS minimal-http-server.c)
+
+include_directories(../../../plugins)
+
+# If we are being built as part of lws, confirm current build config supports
+# reqconfig, else skip building ourselves.
+#
+# If we are being built externally, confirm installed lws was configured to
+# support reqconfig, else error out with a helpful message about the problem.
+#
+MACRO(require_lws_config reqconfig _val result)
+
+	if (DEFINED ${reqconfig})
+	if (${reqconfig})
+		set (rq 1)
+	else()
+		set (rq 0)
+	endif()
+	else()
+		set(rq 0)
+	endif()
+
+	if (${_val} EQUAL ${rq})
+		set(SAME 1)
+	else()
+		set(SAME 0)
+	endif()
+
+	if (LWS_WITH_MINIMAL_EXAMPLES AND NOT ${SAME})
+		if (${_val})
+			message("${SAMP}: skipping as lws being built without ${reqconfig}")
+		else()
+			message("${SAMP}: skipping as lws built with ${reqconfig}")
+		endif()
+		set(${result} 0)
+	else()
+		if (LWS_WITH_MINIMAL_EXAMPLES)
+			set(MET ${SAME})
+		else()
+			CHECK_C_SOURCE_COMPILES("#include <libwebsockets.h>\nint main(void) {\n#if defined(${reqconfig})\n return 0;\n#else\n fail;\n#endif\n return 0;\n}\n" HAS_${reqconfig})
+			if (NOT DEFINED HAS_${reqconfig} OR NOT HAS_${reqconfig})
+				set(HAS_${reqconfig} 0)
+			else()
+				set(HAS_${reqconfig} 1)
+			endif()
+			if ((HAS_${reqconfig} AND ${_val}) OR (NOT HAS_${reqconfig} AND NOT ${_val}))
+				set(MET 1)
+			else()
+				set(MET 0)
+			endif()
+		endif()
+		if (NOT MET)
+			if (${_val})
+				message(FATAL_ERROR "This project requires lws must have been configured with ${reqconfig}")
+			else()
+				message(FATAL_ERROR "Lws configuration of ${reqconfig} is incompatible with this project")
+			endif()
+		endif()
+	
+	endif()
+ENDMACRO()
+
+
+set(requirements 1)
+require_lws_config(LWS_ROLE_H1 1 requirements)
+require_lws_config(LWS_WITHOUT_SERVER 0 requirements)
+
+if (requirements)
+	add_executable(${SAMP} ${SRCS})
+
+	if (websockets_shared)
+		target_link_libraries(${SAMP} websockets_shared)
+		add_dependencies(${SAMP} websockets_shared)
+	else()
+		target_link_libraries(${SAMP} websockets)
+	endif()
+endif()
--- a/minimal-examples/http-server/minimal-http-server-fulltext-search/README.md
+++ b/minimal-examples/http-server/minimal-http-server-fulltext-search/README.md
@ -0,0 +1,18 @@
+# lws minimal http server
+
+## build
+
+```
+ $ cmake . && make
+```
+
+## usage
+
+```
+ $ ./lws-minimal-http-server
+[2018/03/04 09:30:02:7986] USER: LWS minimal http server | visit http://localhost:7681
+[2018/03/04 09:30:02:7986] NOTICE: Creating Vhost 'default' port 7681, 1 protocols, IPv6 on
+```
+
+Visit http://localhost:7681
+
--- a/minimal-examples/http-server/minimal-http-server-fulltext-search/lws-fts.index
+++ b/minimal-examples/http-server/minimal-http-server-fulltext-search/lws-fts.index
--- a/minimal-examples/http-server/minimal-http-server-fulltext-search/minimal-http-server.c
+++ b/minimal-examples/http-server/minimal-http-server-fulltext-search/minimal-http-server.c
@ -0,0 +1,124 @@
+/*
+ * lws-minimal-http-server-fts
+ *
+ * Copyright (C) 2018 Andy Green <andy@warmcat.com>
+ *
+ * This file is made available under the Creative Commons CC0 1.0
+ * Universal Public Domain Dedication.
+ *
+ * This demonstrates how to use lws full-text search
+ */
+
+#include <libwebsockets.h>
+#include <string.h>
+#include <signal.h>
+
+#define LWS_PLUGIN_STATIC
+#include <protocol_fulltext_demo.c>
+
+const char *index_filepath = "./lws-fts.index";
+static int interrupted;
+
+static struct lws_protocols protocols[] = {
+	LWS_PLUGIN_PROTOCOL_FULLTEXT_DEMO,
+	{ NULL, NULL, 0, 0 } /* terminator */
+};
+
+static struct lws_protocol_vhost_options pvo_idx = {
+	NULL,
+	NULL,
+	"indexpath",		/* pvo name */
+	NULL	/* filled in at runtime */
+};
+
+static const struct lws_protocol_vhost_options pvo = {
+	NULL,		/* "next" pvo linked-list */
+	&pvo_idx,	/* "child" pvo linked-list */
+	"lws-test-fts",	/* protocol name we belong to on this vhost */
+	""		/* ignored */
+};
+
+/* override the default mount for /fts in the URL space */
+
+static const struct lws_http_mount mount_fts = {
+	/* .mount_next */		NULL,		/* linked-list "next" */
+	/* .mountpoint */		"/fts",		/* mountpoint URL */
+	/* .origin */			NULL,	/* protocol */
+	/* .def */			NULL,
+	/* .protocol */			"lws-test-fts",
+	/* .cgienv */			NULL,
+	/* .extra_mimetypes */		NULL,
+	/* .interpret */		NULL,
+	/* .cgi_timeout */		0,
+	/* .cache_max_age */		0,
+	/* .auth_mask */		0,
+	/* .cache_reusable */		0,
+	/* .cache_revalidate */		0,
+	/* .cache_intermediaries */	0,
+	/* .origin_protocol */		LWSMPRO_CALLBACK, /* dynamic */
+	/* .mountpoint_len */		4,		/* char count */
+	/* .basic_auth_login_file */	NULL,
+};
+
+static const struct lws_http_mount mount = {
+	/* .mount_next */		&mount_fts,	/* linked-list "next" */
+	/* .mountpoint */		"/",		/* mountpoint URL */
+	/* .origin */			"./mount-origin", /* serve from dir */
+	/* .def */			"index.html",	/* default filename */
+	/* .protocol */			NULL,
+	/* .cgienv */			NULL,
+	/* .extra_mimetypes */		NULL,
+	/* .interpret */		NULL,
+	/* .cgi_timeout */		0,
+	/* .cache_max_age */		0,
+	/* .auth_mask */		0,
+	/* .cache_reusable */		0,
+	/* .cache_revalidate */		0,
+	/* .cache_intermediaries */	0,
+	/* .origin_protocol */		LWSMPRO_FILE,	/* files in a dir */
+	/* .mountpoint_len */		1,		/* char count */
+	/* .basic_auth_login_file */	NULL,
+};
+
+void sigint_handler(int sig)
+{
+	interrupted = 1;
+}
+
+int main(int argc, const char **argv)
+{
+	int n = 0, logs = LLL_USER | LLL_ERR | LLL_WARN | LLL_NOTICE;
+	struct lws_context_creation_info info;
+	struct lws_context *context;
+	const char *p;
+
+	signal(SIGINT, sigint_handler);
+
+	if ((p = lws_cmdline_option(argc, argv, "-d")))
+		logs = atoi(p);
+
+	lws_set_log_level(logs, NULL);
+	lwsl_user("LWS minimal http server fulltext search | "
+		  "visit http://localhost:7681\n");
+
+	memset(&info, 0, sizeof info);
+	info.port = 7681;
+	info.mounts = &mount;
+	info.protocols = protocols;
+	info.pvo = &pvo;
+
+	pvo_idx.value = index_filepath;
+
+	context = lws_create_context(&info);
+	if (!context) {
+		lwsl_err("lws init failed\n");
+		return 1;
+	}
+
+	while (n >= 0 && !interrupted)
+		n = lws_service(context, 1000);
+
+	lws_context_destroy(context);
+
+	return 0;
+}
--- a/minimal-examples/http-server/minimal-http-server-fulltext-search/mount-origin/404.html
+++ b/minimal-examples/http-server/minimal-http-server-fulltext-search/mount-origin/404.html
@ -0,0 +1,9 @@
+<meta charset="UTF-8"> 
+<html>
+	<body>
+		<img src="libwebsockets.org-logo.png"><br>
+		<h1>404</h1>
+		Sorry, that file doesn't exist.
+	</body>
+</html>
+
--- a/minimal-examples/http-server/minimal-http-server-fulltext-search/mount-origin/dorian-gray-wikipedia.jpg
+++ b/minimal-examples/http-server/minimal-http-server-fulltext-search/mount-origin/dorian-gray-wikipedia.jpg
--- a/minimal-examples/http-server/minimal-http-server-fulltext-search/mount-origin/favicon.ico
+++ b/minimal-examples/http-server/minimal-http-server-fulltext-search/mount-origin/favicon.ico
--- a/minimal-examples/http-server/minimal-http-server-fulltext-search/mount-origin/index.html
+++ b/minimal-examples/http-server/minimal-http-server-fulltext-search/mount-origin/index.html
@ -0,0 +1,29 @@
+<!DOCTYPE html>
+<html>
+
+<head>
+ <meta charset=utf-8 http-equiv="Content-Language" content="en"/>
+ <script src="lws-fts.js"></script>
+ <link rel="stylesheet" type="text/css" href="lws-fts.css"/>
+</head>
+
+<body>
+<img src="./libwebsockets.org-logo.png"><br>
+<div class="searchbg">
+
+<span class="title">The Picture of Dorian Gray</span><br>
+
+	<table class="searchtable">
+		<tr>
+		 <td rowspan='2'><img class='eyeglass'></td>
+		    <td class='searchboxtitle'>Fulltext search<br>
+			<input type='text' id='lws_fts' class='nonviable'
+				name='lws_fts' maxlength='80'>
+		<div class='acomplete' id='acomplete'></div>
+		</td></tr></table>
+
+	<div class='searchresults' id='searchresults'></div>
+</div>
+</body>
+</html>
+
--- a/minimal-examples/http-server/minimal-http-server-fulltext-search/mount-origin/libwebsockets.org-logo.png
+++ b/minimal-examples/http-server/minimal-http-server-fulltext-search/mount-origin/libwebsockets.org-logo.png
--- a/minimal-examples/http-server/minimal-http-server-fulltext-search/mount-origin/lws-fts.css
+++ b/minimal-examples/http-server/minimal-http-server-fulltext-search/mount-origin/lws-fts.css
--- a/minimal-examples/http-server/minimal-http-server-fulltext-search/mount-origin/lws-fts.js
+++ b/minimal-examples/http-server/minimal-http-server-fulltext-search/mount-origin/lws-fts.js
@ -0,0 +1,211 @@
+/* lws-fts.js - JS supporting lws fulltext search
+ *
+ * Copyright (C) 2018 Andy Green <andy@warmcat.com>
+ *
+ *  This library is free software; you can redistribute it and/or
+ *  modify it under the terms of the GNU Lesser General Public
+ *  License as published by the Free Software Foundation:
+ *  version 2.1 of the License.
+ */
+
+(function() {
+	
+	var last_ac = "";
+	
+	function san(s)
+	{
+		s.replace("<", "!");
+		s.replace("%", "!");
+		
+		return s;
+	}
+	
+	function lws_fts_choose()
+	{
+		var xhr = new XMLHttpRequest();
+		var sr = document.getElementById("searchresults");
+		var ac = document.getElementById("acomplete");
+		var inp = document.getElementById("lws_fts");
+
+		xhr.onopen = function(e) {
+			xhr.setRequestHeader("cache-control", "max-age=0");
+		};
+
+		xhr.onload = function(e) {	
+			var jj, n, m, s = "", x, lic = 0, hl, re;
+			var sr = document.getElementById("searchresults");
+			var ac = document.getElementById("acomplete");
+			var inp = document.getElementById("lws_fts");
+			sr.style.width = (parseInt(sr.parentNode.offsetWidth, 10) - 88) + "px";
+			sr.style.opacity = "1";
+			inp.blur();
+			
+			hl = document.getElementById("lws_fts").value;
+			re = new RegExp(hl, "gi");
+			
+			// console.log(xhr.responseText);
+			jj = JSON.parse(xhr.responseText);
+			
+			if (jj.fp) {
+				lic = jj.fp.length;						
+				for (n = 0; n < lic; n++) {
+					var q;
+					
+					s += "<div class='filepath'>" + jj.fp[n].path + "</div>";
+					
+					s += "<table>";
+					for (m = 0; m < jj.fp[n].hits.length; m++)
+						s += "<tr><td class='r'>" + jj.fp[n].hits[m].l +
+							 "</td><td>" + jj.fp[n].hits[m].s +
+							 "</td></tr>";
+					
+					s += "</table>";
+	
+				}
+			}
+			
+			sr.innerHTML = s;
+		};
+		
+		inp.blur();
+		ac.style.opacity = "0";
+		sr.style.innerHTML = "";
+		xhr.open("GET", "../fts/r/" + document.getElementById("lws_fts").value);
+		xhr.send();
+	}
+	
+	function lws_fts_ac_select(e)
+	{
+		var t = e.target;
+
+		while (t) {
+			if (t.getAttribute && t.getAttribute("string")) {
+				document.getElementById("lws_fts").value =
+						t.getAttribute("string");
+
+				lws_fts_choose();
+			}
+
+			t = t.parentNode;
+		}
+	}
+	
+	function lws_fts_search_input()
+	{
+		var ac = document.getElementById("acomplete"),
+		    sb = document.getElementById("lws_fts");
+		
+		if (last_ac === sb.value)
+			return;
+		
+		last_ac = sb.value;
+		
+		ac.style.width = (parseInt(sb.offsetWidth, 10) - 2) + "px";
+		ac.style.opacity = "1";
+		
+		/* detect loss of focus for popup menu */
+		sb.addEventListener("focusout", function(e) {
+				ac.style.opacity = "0";
+		});
+		
+		
+		var xhr = new XMLHttpRequest();
+
+		xhr.onopen = function(e) {
+			xhr.setRequestHeader("cache-control", "max-age=0");
+		};
+		xhr.onload = function(e) {
+			var jj, n, s = "", x, lic = 0;
+			var inp = document.getElementById("lws_fts");
+			var ac = document.getElementById("acomplete");
+			
+			// console.log(xhr.responseText);
+			jj = JSON.parse(xhr.responseText);
+			
+			switch(parseInt(jj.indexed, 10)) {
+			case 0: /* there is no index */
+				break;
+
+			case 1: /* yay there is an index */
+			
+					if (jj.ac) {
+						lic = jj.ac.length;
+						s += "<ul id='menu-ul'>";
+						for (n = 0; n < lic; n++) {
+
+							if (jj.ac[n] && parseInt(jj.ac[n].matches, 10))
+								s += "<li id='mi_ac" + n + "' string='" +
+									san(jj.ac[n].ac) + 
+									"'><table><tr><td>" + san(jj.ac[n].ac) +
+									"</td><td class='r'>" +
+									parseInt(jj.ac[n].matches, 10) +
+									"</td></tr></table></li>";
+						}
+						
+						s += "</ul>";
+
+					 if (!lic) {
+						//s = "<img class='noentry'>";
+						inp.className = "nonviable";
+						ac.style.opacity = "0";
+					 } else {
+						 inp.className = "viable";
+						 ac.style.opacity = "1";
+					 }
+					}
+
+				break;
+				
+			default:
+				
+				/* an index is being built... */
+				
+				s = "<table><tr><td><img class='spinner'></td><td>" +
+					"<table><tr><td>Indexing</td></tr><tr><td>" +
+					"<div id='bar1' class='bar1'>" +
+					"<div id='bar2' class='bar2'>" +
+					jj.index_done + "&nbsp;/&nbsp;" + jj.index_files +
+					"</div></div></td></tr></table>" +
+					"</td></tr></table>";
+			
+				setTimeout(lws_fts_search_input, 300);
+			
+				break;
+			}
+			
+			ac.innerHTML = s;
+			
+			for (n = 0; n < lic; n++)
+				if (document.getElementById("mi_ac" + n))
+					document.getElementById("mi_ac" + n).
+						addEventListener("click", lws_fts_ac_select);
+			if (jj.index_files) {
+				document.getElementById("bar2").style.width =
+					((150 * jj.index_done) / (jj.index_files + 1)) + "px";
+			}
+		};
+		
+		xhr.open("GET", "../fts/a/" + document.getElementById("lws_fts").value);
+		xhr.send();
+	}
+
+	document.addEventListener("DOMContentLoaded", function() {
+		var inp = document.getElementById("lws_fts");
+
+		inp.addEventListener("input", lws_fts_search_input, false);
+
+		inp.addEventListener("keydown",
+				function(e) {
+			var inp = document.getElementById("lws_fts");
+			var sr = document.getElementById("searchresults");
+			var ac = document.getElementById("acomplete");
+			if (e.key === "Enter" && inp.className === "viable") {
+				lws_fts_choose();
+				sr.focus();
+				ac.style.opacity = "0";
+			}
+		}, false);
+
+	}, false);
+	
+}());
--- a/minimal-examples/http-server/minimal-http-server-fulltext-search/the-picture-of-dorian-gray.txt
+++ b/minimal-examples/http-server/minimal-http-server-fulltext-search/the-picture-of-dorian-gray.txt
--- a/minimal-examples/selftests-library.sh
+++ b/minimal-examples/selftests-library.sh
@ -57,7 +57,7 @@ dotest() {
 	T=$3
 	(
 		{
-			/usr/bin/time -p $1/lws-$MYTEST $4 $5 $6 $7 > $2/$MYTEST/$T.log 2> $2/$MYTEST/$T.log ;
+			/usr/bin/time -p $1/lws-$MYTEST $4 $5 $6 $7 $8 $9 > $2/$MYTEST/$T.log 2> $2/$MYTEST/$T.log ;
 			echo $? > $2/$MYTEST/$T.result
 		} 2> $2/$MYTEST/$T.time >/dev/null
 	) >/dev/null 2> /dev/null &
--- a/plugins/protocol_fulltext_demo.c
+++ b/plugins/protocol_fulltext_demo.c
@ -0,0 +1,293 @@
+/*
+ * ws protocol handler plugin for "fulltext demo"
+ *
+ * Copyright (C) 2010-2018 Andy Green <andy@warmcat.com>
+ *
+ * This file is made available under the Creative Commons CC0 1.0
+ * Universal Public Domain Dedication.
+ *
+ * The person who associated a work with this deed has dedicated
+ * the work to the public domain by waiving all of his or her rights
+ * to the work worldwide under copyright law, including all related
+ * and neighboring rights, to the extent allowed by law. You can copy,
+ * modify, distribute and perform the work, even for commercial purposes,
+ * all without asking permission.
+ *
+ * These test plugins are intended to be adapted for use in your code, which
+ * may be proprietary.  So unlike the library itself, they are licensed
+ * Public Domain.
+ */
+
+#if !defined (LWS_PLUGIN_STATIC)
+#define LWS_DLL
+#define LWS_INTERNAL
+#include <libwebsockets.h>
+#endif
+
+#include <stdlib.h>
+#include <string.h>
+#include <fcntl.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#ifdef WIN32
+#include <io.h>
+#endif
+#include <stdio.h>
+
+struct vhd_fts_demo {
+	const char *indexpath;
+};
+
+struct pss_fts_demo {
+	struct lwsac *result;
+	struct lws_fts_result_autocomplete *ac;
+	struct lws_fts_result_filepath *fp;
+
+	uint32_t *li;
+	int done;
+
+	uint8_t first:1;
+	uint8_t ac_done:1;
+
+	uint8_t fp_init_done:1;
+};
+
+static int
+callback_fts(struct lws *wsi, enum lws_callback_reasons reason, void *user,
+	     void *in, size_t len)
+{
+	struct vhd_fts_demo *vhd = (struct vhd_fts_demo *)
+		lws_protocol_vh_priv_get(lws_get_vhost(wsi),
+					 lws_get_protocol(wsi));
+	struct pss_fts_demo *pss = (struct pss_fts_demo *)user;
+	uint8_t buf[LWS_PRE + 2048], *start = &buf[LWS_PRE], *p = start,
+		*end = &buf[sizeof(buf) - LWS_PRE - 1];
+	struct lws_fts_search_params params;
+	const char *ccp = (const char *)in;
+	struct lws_fts_result *result;
+	struct lws_fts_file *jtf;
+	int n;
+
+	switch (reason) {
+
+	case LWS_CALLBACK_PROTOCOL_INIT:
+		vhd = lws_protocol_vh_priv_zalloc(lws_get_vhost(wsi),
+			     lws_get_protocol(wsi),sizeof(struct vhd_fts_demo));
+		if (!vhd)
+			return 1;
+		if (lws_pvo_get_str(in, "indexpath",
+				    (const char **)&vhd->indexpath))
+			return 1;
+
+		return 0;
+
+	case LWS_CALLBACK_HTTP:
+
+		pss->first = 1;
+		pss->ac_done = 0;
+
+		/*
+		 * we have a "subdirectory" selecting the task
+		 *
+		 * /a/ = autocomplete
+		 * /r/ = results
+		 */
+
+		if (strncmp(ccp, "/a/", 3) && strncmp(ccp, "/r/", 3))
+			goto reply_404;
+
+		memset(&params, 0, sizeof(params));
+
+		params.needle = ccp + 3;
+		if (*(ccp + 1) == 'a')
+			params.flags = LWSFTS_F_QUERY_AUTOCOMPLETE;
+		if (*(ccp + 1) == 'r')
+			params.flags = LWSFTS_F_QUERY_FILES |
+				       LWSFTS_F_QUERY_FILE_LINES |
+				       LWSFTS_F_QUERY_QUOTE_LINE;
+		params.max_autocomplete = 10;
+		params.max_files = 10;
+
+		jtf = lws_fts_open(vhd->indexpath);
+		if (!jtf) {
+			lwsl_err("unable to open %s\n", vhd->indexpath);
+			/* we'll inform the client in the JSON */
+			goto reply_200;
+		}
+
+		result = lws_fts_search(jtf, &params);
+		lws_fts_close(jtf);
+		if (result) {
+			pss->result = params.results_head;
+			pss->ac = result->autocomplete_head;
+			pss->fp = result->filepath_head;
+		}
+		/* NULL result will be told in the json as "indexed": 0 */
+
+reply_200:
+		if (lws_add_http_common_headers(wsi, HTTP_STATUS_OK,
+						"text/html",
+					LWS_ILLEGAL_HTTP_CONTENT_LEN, &p, end))
+			return 1;
+
+		if (lws_finalize_write_http_header(wsi, start, &p, end))
+			return 1;
+
+		lws_callback_on_writable(wsi);
+		return 0;
+
+reply_404:
+		if (lws_add_http_common_headers(wsi, HTTP_STATUS_NOT_FOUND,
+						"text/html",
+					LWS_ILLEGAL_HTTP_CONTENT_LEN, &p, end))
+			return 1;
+
+		if (lws_finalize_write_http_header(wsi, start, &p, end))
+			return 1;
+		return lws_http_transaction_completed(wsi);
+
+	case LWS_CALLBACK_CLOSED_HTTP:
+		if (pss && pss->result)
+			lwsac_free(&pss->result);
+		break;
+
+	case LWS_CALLBACK_HTTP_WRITEABLE:
+
+		if (!pss)
+			break;
+
+		n = LWS_WRITE_HTTP;
+		if (pss->first)
+			p += lws_snprintf((char *)p, lws_ptr_diff(end, p),
+				"{\"indexed\": %d, \"ac\": [", !!pss->result);
+
+		while (pss->ac && lws_ptr_diff(end, p) > 256) {
+			p += lws_snprintf((char *)p, lws_ptr_diff(end, p),
+				"%c{\"ac\": \"%s\",\"matches\": %d,"
+				"\"agg\": %d, \"elided\": %d}",
+				pss->first ? ' ' : ',', (char *)(pss->ac + 1),
+				pss->ac->instances, pss->ac->agg_instances,
+				pss->ac->elided);
+
+			pss->first = 0;
+			pss->ac = pss->ac->next;
+		}
+
+		if (!pss->ac_done && !pss->ac && pss->fp) {
+			pss->ac_done = 1;
+
+			p += lws_snprintf((char *)p, lws_ptr_diff(end, p),
+					  "], \"fp\": [");
+		}
+
+		while (pss->fp && lws_ptr_diff(end, p) > 256) {
+			if (!pss->fp_init_done) {
+				p += lws_snprintf((char *)p,
+					lws_ptr_diff(end, p),
+					"%c{\"path\": \"%s\",\"matches\": %d,"
+					"\"origlines\": %d,"
+					"\"hits\": [", pss->first ? ' ' : ',',
+					((char *)(pss->fp + 1)) +
+						pss->fp->matches_length,
+					pss->fp->matches,
+					pss->fp->lines_in_file);
+
+				pss->li = ((uint32_t *)(pss->fp + 1));
+				pss->done = 0;
+				pss->fp_init_done = 1;
+				pss->first = 0;
+			} else {
+				while (pss->done < pss->fp->matches &&
+				       lws_ptr_diff(end, p) > 256) {
+
+					p += lws_snprintf((char *)p,
+						lws_ptr_diff(end, p),
+						"%c\n{\"l\":%d,\"o\":%d,"
+						"\"s\":\"%s\"}",
+						!pss->done ? ' ' : ',',
+						pss->li[0], pss->li[1],
+						*((const char **)&pss->li[2]));
+					pss->li += 2 + (sizeof(const char *) /
+							sizeof(uint32_t));
+					pss->done++;
+				}
+
+				if (pss->done == pss->fp->matches) {
+					*p++ = ']';
+					pss->fp_init_done = 0;
+					pss->fp = pss->fp->next;
+					if (!pss->fp)
+						*p++ = '}';
+				}
+			}
+		}
+
+		if (!pss->ac && !pss->fp) {
+			n = LWS_WRITE_HTTP_FINAL;
+			p += lws_snprintf((char *)p, lws_ptr_diff(end, p),
+						"]}");
+		}
+
+		if (lws_write(wsi, (uint8_t *)start,
+			      lws_ptr_diff(p, start), n) !=
+					      lws_ptr_diff(p, start))
+			return 1;
+
+		if (n == LWS_WRITE_HTTP_FINAL) {
+			if (pss->result)
+				lwsac_free(&pss->result);
+			if (lws_http_transaction_completed(wsi))
+				return -1;
+		} else
+			lws_callback_on_writable(wsi);
+
+		return 0;
+
+	default:
+		break;
+	}
+
+	return lws_callback_http_dummy(wsi, reason, user, in, len);
+}
+
+
+#define LWS_PLUGIN_PROTOCOL_FULLTEXT_DEMO \
+	{ \
+		"lws-test-fts", \
+		callback_fts, \
+		sizeof(struct pss_fts_demo), \
+		0, \
+		0, NULL, 0 \
+	}
+
+#if !defined (LWS_PLUGIN_STATIC)
+
+static const struct lws_protocols protocols[] = {
+	LWS_PLUGIN_PROTOCOL_FULLTEXT_DEMO
+};
+
+LWS_EXTERN LWS_VISIBLE int
+init_protocol_fulltext_demo(struct lws_context *context,
+			struct lws_plugin_capability *c)
+{
+	if (c->api_magic != LWS_PLUGIN_API_MAGIC) {
+		lwsl_err("Plugin API %d, library API %d", LWS_PLUGIN_API_MAGIC,
+			 c->api_magic);
+		return 1;
+	}
+
+	c->protocols = protocols;
+	c->count_protocols = LWS_ARRAY_SIZE(protocols);
+	c->extensions = NULL;
+	c->count_extensions = 0;
+
+	return 0;
+}
+
+LWS_EXTERN LWS_VISIBLE int
+destroy_protocol_fulltext_demo(struct lws_context *context)
+{
+	return 0;
+}
+
+#endif
--- a/plugins/protocol_lws_sshd_demo.c
+++ b/plugins/protocol_lws_sshd_demo.c
@ -208,7 +208,8 @@ ssh_ops_get_server_key(struct lws *wsi, uint8_t *buf, size_t len)
 						 lws_get_protocol(wsi));
 	int n;

-	lseek(vhd->privileged_fd, 0, SEEK_SET);
+	if (lseek(vhd->privileged_fd, 0, SEEK_SET) < 0)
+		return 0;
 	n = read(vhd->privileged_fd, buf, (int)len);
 	if (n < 0) {
 		lwsl_err("%s: read failed: %d\n", __func__, n);