4 CMake is a multi-platform build tool that can generate build files for many
5 different target platforms. See more info at http://www.cmake.org
7 CMake also allows/recommends you to do "out of source"-builds, that is,
8 the build files are separated from your sources, so there is no need to
9 create elaborate clean scripts to get a clean source tree, instead you
10 simply remove your build directory.
12 Libwebsockets has been tested to build successfully on the following platforms
13 with SSL support (both OpenSSL/wolfSSL):
15 - Windows (Visual Studio)
21 Building the library and test apps
22 ----------------------------------
24 The project settings used by CMake to generate the platform specific build
25 files is called [CMakeLists.txt](CMakeLists.txt). CMake then uses one of its "Generators" to
26 output a Visual Studio project or Make file for instance. To see a list of
27 the available generators for your platform, simply run the "cmake" command.
29 Note that by default OpenSSL will be linked, if you don't want SSL support
30 see below on how to toggle compile options.
35 1. Install CMake 2.8 or greater: http://cmake.org/cmake/resources/software.html
36 (Most Unix distributions comes with a packaged version also)
40 3. Generate the build files (default is Make files):
49 (**NOTE**: The `build/`` directory can have any name and be located anywhere
50 on your filesystem, and that the argument `..` given to cmake is simply
51 the source directory of **libwebsockets** containing the [CMakeLists.txt](CMakeLists.txt)
52 project file. All examples in this file assumes you use "..")
55 A common option you may want to give is to set the install path, same
56 as --prefix= with autotools. It defaults to /usr/local.
57 You can do this by, eg
60 $ cmake -DCMAKE_INSTALL_PREFIX:PATH=/usr ..
64 On machines that want libraries in lib64, you can also add the
65 following to the cmake line
72 If you are building against a non-distro OpenSSL (eg, in order to get
73 access to ALPN support only in newer OpenSSL versions) the nice way to
74 express that in one cmake command is eg,
77 $ cmake .. -DOPENSSL_ROOT_DIR=/usr/local/ssl \
78 -DCMAKE_INCLUDE_DIRECTORIES_PROJECT_BEFORE=/usr/local/ssl \
82 When you run the test apps using non-distro SSL, you have to force them
83 to use your libs, not the distro ones
86 $ LD_LIBRARY_PATH=/usr/local/ssl/lib libwebsockets-test-server --ssl
89 4. Finally you can build using the generated Makefile:
98 When changing cmake options, for some reason the only way to get it to see the
99 changes sometimes is delete the contents of your build directory and do the
102 Building on Windows (Visual Studio)
103 -----------------------------------
104 1. Install CMake 2.6 or greater: http://cmake.org/cmake/resources/software.html
106 2. Install OpenSSL binaries. http://www.openssl.org/related/binaries.html
108 (**NOTE**: Preferably in the default location to make it easier for CMake to find them)
111 Be sure that OPENSSL_CONF environment variable is defined and points at
112 <OpenSSL install location>\bin\openssl.cfg
114 3. Generate the Visual studio project by opening the Visual Studio cmd prompt:
120 cmake -G "Visual Studio 10" ..
123 (**NOTE**: There is also a cmake-gui available on Windows if you prefer that)
126 See this link to find out the version number corresponding to your Visual Studio edition:
127 http://superuser.com/a/194065
129 4. Now you should have a generated Visual Studio Solution in your
130 `<path to src>/build` directory, which can be used to build.
132 Building on Windows (MinGW)
133 ---------------------------
134 1. Install MinGW: http://sourceforge.net/projects/mingw/files
136 (**NOTE**: Preferably in the default location C:\MinGW)
138 2. Fix up MinGW headers
140 a) Add the following lines to C:\MinGW\include\winsock2.h:
142 #if(_WIN32_WINNT >= 0x0600)
144 typedef struct pollfd {
150 } WSAPOLLFD, *PWSAPOLLFD, FAR *LPWSAPOLLFD;
152 WINSOCK_API_LINKAGE int WSAAPI WSAPoll(LPWSAPOLLFD fdArray, ULONG fds, INT timeout);
154 #endif // (_WIN32_WINNT >= 0x0600)
156 b) Create C:\MinGW\include\mstcpip.h and copy and paste the content from following link into it:
158 http://wine-unstable.sourcearchive.com/documentation/1.1.32/mstcpip_8h-source.html
160 3. Install CMake 2.6 or greater: http://cmake.org/cmake/resources/software.html
162 4. Install OpenSSL binaries. http://www.openssl.org/related/binaries.html
164 (**NOTE**: Preferably in the default location to make it easier for CMake to find them)
167 Be sure that OPENSSL_CONF environment variable is defined and points at
168 <OpenSSL install location>\bin\openssl.cfg
170 5. Generate the build files (default is Make files) using MSYS shell:
173 $ cd /drive/path/to/src
176 $ cmake -G "MSYS Makefiles" -DCMAKE_INSTALL_PREFIX=C:/MinGW ..
179 (**NOTE**: The `build/`` directory can have any name and be located anywhere
180 on your filesystem, and that the argument `..` given to cmake is simply
181 the source directory of **libwebsockets** containing the [CMakeLists.txt](CMakeLists.txt)
182 project file. All examples in this file assumes you use "..")
185 To generate build files allowing to create libwebsockets binaries with debug information
186 set the CMAKE_BUILD_TYPE flag to DEBUG:
189 $ cmake -G "MSYS Makefiles" -DCMAKE_INSTALL_PREFIX=C:/MinGW -DCMAKE_BUILD_TYPE=DEBUG ..
192 6. Finally you can build using the generated Makefile and get the results deployed into your MinGW installation:
199 Setting compile options
200 -----------------------
202 To set compile time flags you can either use one of the CMake gui applications
203 or do it via command line.
207 To list avaialable options (ommit the H if you don't want the help text):
211 Then to set an option and build (for example turn off SSL support):
213 cmake -DLWS_WITH_SSL=0 ..
215 cmake -DLWS_WITH_SSL:BOOL=OFF ..
219 If you have a curses-enabled build you simply type:
220 (not all packages include this, my debian install does not for example).
226 On windows CMake comes with a gui application:
227 Start -> Programs -> CMake -> CMake (cmake-gui)
229 wolfSSL/CyaSSL replacement for OpenSSL
230 --------------------------------------
231 wolfSSL/CyaSSL is a lightweight SSL library targeted at embedded systems:
232 https://www.wolfssl.com/wolfSSL/Products-wolfssl.html
234 It contains a OpenSSL compatibility layer which makes it possible to pretty
235 much link to it instead of OpenSSL, giving a much smaller footprint.
237 **NOTE**: wolfssl needs to be compiled using the `--enable-opensslextra` flag for
240 Compiling libwebsockets with wolfSSL
241 ------------------------------------
244 cmake .. -DLWS_USE_WOLFSSL=1 \
245 -DLWS_WOLFSSL_INCLUDE_DIRS=/path/to/wolfssl \
246 -DLWS_WOLFSSL_LIBRARIES=/path/to/wolfssl/wolfssl.a ..
249 **NOTE**: On windows use the .lib file extension for `LWS_WOLFSSL_LIBRARIES` instead.
251 Compiling libwebsockets with CyaSSL
252 -----------------------------------
255 cmake .. -DLWS_USE_CYASSL=1 \
256 -DLWS_CYASSL_INCLUDE_DIRS=/path/to/cyassl \
257 -DLWS_CYASSL_LIBRARIES=/path/to/wolfssl/cyassl.a ..
260 **NOTE**: On windows use the .lib file extension for `LWS_CYASSL_LIBRARIES` instead.
262 Reproducing HTTP2.0 tests
263 -------------------------
265 You must have built and be running lws against a version of openssl that has
266 ALPN / NPN. Most distros still have older versions. You'll know it's right by
270 lwsts[4752]: Compiled with OpenSSL support
271 lwsts[4752]: Using SSL mode
272 lwsts[4752]: HTTP2 / ALPN enabled
277 For non-SSL HTTP2.0 upgrade
280 $ nghttp -nvasu http://localhost:7681/test.htm
283 For SSL / ALPN HTTP2.0 upgrade
286 $ nghttp -nvas https://localhost:7681/test.html
291 To enable cross-compiling **libwebsockets** using CMake you need to create
292 a "Toolchain file" that you supply to CMake when generating your build files.
293 CMake will then use the cross compilers and build paths specified in this file
294 to look for dependencies and such.
296 **Libwebsockets** includes an example toolchain file [cross-arm-linux-gnueabihf.cmake](cross-arm-linux-gnueabihf.cmake)
297 you can use as a starting point.
299 The commandline to configure for cross with this would look like
302 $ cmake .. -DCMAKE_INSTALL_PREFIX:PATH=/usr \
303 -DCMAKE_TOOLCHAIN_FILE=../cross-arm-linux-gnueabihf.cmake \
304 -DWITHOUT_EXTENSIONS=1 -DWITH_SSL=0
307 The example shows how to build with no external cross lib dependencies, you
308 need to provide the cross libraries otherwise.
310 **NOTE**: start from an EMPTY build directory if you had a non-cross build in there
311 before the settings will be cached and your changes ignored.
313 Additional information on cross compilation with CMake:
314 http://www.vtk.org/Wiki/CMake_Cross_Compiling
319 Embedded server-only configuration without extensions (ie, no compression
320 on websocket connections), but with full v13 websocket features and http
321 server, built on ARM Cortex-A9:
323 Update at 8dac94d (2013-02-18)
326 $ ./configure --without-client --without-extensions --disable-debug --without-daemonize
328 Context Creation, 1024 fd limit[2]: 16720 (includes 12 bytes per fd)
329 Per-connection [3]: 72 bytes, +1328 during headers
331 .text .rodata .data .bss
335 This shows the impact of the major configuration with/without options at
336 13ba5bbc633ea962d46d using Ubuntu ARM on a PandaBoard ES.
338 These are accounting for static allocations from the library elf, there are
339 additional dynamic allocations via malloc. These are a bit old now but give
340 the right idea for relative "expense" of features.
342 Static allocations, ARM9
344 | | .text | .rodata | .data | .bss |
345 |--------------------------------|---------|---------|-------|------|
346 | All (no without) | 35024 | 9940 | 336 | 4104 |
347 | without client | 25684 | 7144 | 336 | 4104 |
348 | without client, exts | 21652 | 6288 | 288 | 4104 |
349 | without client, exts, debug[1] | 19756 | 3768 | 288 | 4104 |
350 | without server | 30304 | 8160 | 336 | 4104 |
351 | without server, exts | 25382 | 7204 | 288 | 4104 |
352 | without server, exts, debug[1] | 23712 | 4256 | 288 | 4104 |
354 [1] `--disable-debug` only removes messages below `lwsl_notice`. Since that is
355 the default logging level the impact is not noticeable, error, warn and notice
356 logs are all still there.
358 [2] `1024` fd per process is the default limit (set by ulimit) in at least Fedora
359 and Ubuntu. You can make significant savings tailoring this to actual expected
360 peak fds, ie, at a limit of `20`, context creation allocation reduces to `4432 +
363 [3] known header content is freed after connection establishment