Home | History | Annotate | Download | only in sdk
      1 .. _sdk-examples-2:
      2 
      3 Running the SDK Examples
      4 ========================
      5 
      6 Every Native Client SDK bundle comes with a folder of example applications.
      7 Each example demonstrates one or two key Native Client programming concepts.
      8 After you've :doc:`downloaded the SDK <download>`, follow the instructions
      9 on this page to build and run the examples.
     10 
     11 Configure the Google Chrome Browser
     12 -----------------------------------
     13 
     14 #. Your version of Chrome must be equal to or greater than the version of
     15    your SDK bundle. For example, if you're developing with the ``pepper_31``
     16    bundle, you must use Google Chrome version 31 or greater. To find out what
     17    version of Chrome you're using, type ``about:chrome`` or ``about:version``
     18    in the Chrome address bar.
     19 
     20 #. For Portable Native Client, no extra Chrome flags are needed as of
     21    Chrome version 31.
     22 
     23    For other Native Client applications, or to **debug** Portable Native
     24    Client applications by translating the **pexe** to a **nexe** ahead of
     25    time, enable the Native Client flag. Native Client is enabled by default
     26    only for applications distributed through the Chrome Web Store. To run
     27    Native Client applications that are not distributed through the Chrome
     28    Web Store, like the SDK examples, you must specifically enable the Native
     29    Client flag in Chrome:
     30 
     31    * Type ``about:flags`` in the Chrome address bar and scroll down to
     32      "Native Client".
     33    * If the link below "Native Client" says "Disable", then Native Client is
     34      already enabled and you don't need to do anything else.
     35    * If the link below "Native Client" says "Enable", click the "Enable"
     36      link, scroll down to the bottom of the page, and click the "Relaunch
     37      Now" button. All browser windows will restart when you relaunch Chrome.
     38 
     39 #. Disable the Chrome cache. Chrome caches resources aggressively; when you
     40    are building a Native Client application you should disable the cache to
     41    make sure that Chrome loads the latest version:
     42 
     43    * Open Chrome's developer tools by clicking the menu icon |menu-icon| and
     44      choosing Tools > Developer tools.
     45    * Click the gear icon |gear-icon| in the bottom right corner of the
     46      Chrome window.
     47    * Under the "General" settings, check the box next to "Disable cache".
     48 
     49 Build the SDK examples
     50 ----------------------
     51 
     52 Starting with the ``pepper_24`` bundle, the Makefile scripts for the SDK
     53 examples build multiple versions of the examples using all three SDK
     54 toolchains (newlib, glibc, and PNaCl) and in both release and debug
     55 configurations.  (Note that some examples build only with the particular
     56 toolchains).
     57 
     58 To build all the examples, go to the examples directory in a specific SDK
     59 bundle and run ``make``::
     60 
     61   $ cd pepper_31/examples
     62   $ make
     63   make -C api  all
     64   make[1]: Entering directory `pepper_31/examples/api'
     65   make -C audio  all
     66   make[2]: Entering directory `pepper_31/examples/api/audio'
     67     CXX  newlib/Debug/audio_x86_32.o
     68     LINK newlib/Debug/audio_x86_32.nexe
     69     CXX  newlib/Debug/audio_x86_64.o
     70     LINK newlib/Debug/audio_x86_64.nexe
     71     CXX  newlib/Debug/audio_arm.o
     72     LINK newlib/Debug/audio_arm.nexe
     73     CREATE_NMF newlib/Debug/audio.nmf
     74   make[2]: Leaving directory `pepper_31/examples/api/audio'
     75   make -C url_loader  all
     76   make[2]: Entering directory `pepper_31/examples/api/url_loader'
     77     CXX  newlib/Debug/url_loader_x86_32.o
     78   ...
     79 
     80 Calling ``make`` from inside a particular example's directory will build only
     81 that example::
     82 
     83   $ cd pepper_31/examples/api/core
     84   $ make
     85     CXX  newlib/Debug/core_x86_32.o
     86     LINK newlib/Debug/core_x86_32.nexe
     87     CXX  newlib/Debug/core_x86_64.o
     88     LINK newlib/Debug/core_x86_64.nexe
     89     CXX  newlib/Debug/core_arm.o
     90     LINK newlib/Debug/core_arm.nexe
     91     CREATE_NMF newlib/Debug/core.nmf
     92 
     93 You can call ``make`` with the ``TOOLCHAIN`` and ``CONFIG`` parameters to
     94 override the defaults::
     95 
     96   $ make TOOLCHAIN=pnacl CONFIG=Release
     97     CXX  pnacl/Release/core_pnacl.o
     98     LINK pnacl/Release/core.bc
     99     FINALIZE pnacl/Release/core.pexe
    100     CREATE_NMF pnacl/Release/core.nmf
    101 
    102 
    103 You can also set ``TOOLCHAIN`` to "all" to build one or more examples with
    104 all available toolchains::
    105 
    106   $ make TOOLCHAIN=all
    107   make TOOLCHAIN=newlib
    108   make[1]: Entering directory `pepper_31/examples/api/core'
    109     CXX  newlib/Debug/core_x86_32.o
    110     LINK newlib/Debug/core_x86_32.nexe
    111     CXX  newlib/Debug/core_x86_64.o
    112     LINK newlib/Debug/core_x86_64.nexe
    113     CXX  newlib/Debug/core_arm.o
    114     LINK newlib/Debug/core_arm.nexe
    115     CREATE_NMF newlib/Debug/core.nmf
    116   make[1]: Leaving directory `pepper_31/examples/api/core'
    117   make TOOLCHAIN=glibc
    118   make[1]: Entering directory `pepper_31/examples/api/core'
    119     CXX  glibc/Debug/core_x86_32.o
    120     LINK glibc/Debug/core_x86_32.nexe
    121     CXX  glibc/Debug/core_x86_64.o
    122     LINK glibc/Debug/core_x86_64.nexe
    123     CREATE_NMF glibc/Debug/core.nmf
    124   make[1]: Leaving directory `pepper_31/examples/api/core'
    125   make TOOLCHAIN=pnacl
    126   make[1]: Entering directory `pepper_31/examples/api/core'
    127     CXX  pnacl/Debug/core.o
    128     LINK pnacl/Debug/core_unstripped.bc
    129     FINALIZE pnacl/Debug/core_unstripped.pexe
    130     CREATE_NMF pnacl/Debug/core.nmf
    131   make[1]: Leaving directory `pepper_31/examples/api/core'
    132   make TOOLCHAIN=linux
    133   make[1]: Entering directory `pepper_31/examples/api/core'
    134     CXX  linux/Debug/core.o
    135     LINK linux/Debug/core.so
    136   make[1]: Leaving directory `pepper_31/examples/api/core'
    137 
    138 
    139 After running ``make``, each example directory will contain one or more of
    140 the following subdirectories:
    141 
    142 * a ``newlib`` directory with subdirectories ``Debug`` and ``Release``;
    143 * a ``glibc`` directory with subdirectories ``Debug`` and ``Release``;
    144 * a ``pnacl`` directory with subdirectories ``Debug`` and ``Release``;
    145 
    146 For the newlib and glibc toolchains the Debug and Release subdirectories
    147 contain .nexe files for all target architectures. For the PNaCl toolchain
    148 they contain a single .pexe file. PNaCl debug also produces pre-translated
    149 .nexe files, for ease of debugging. All Debug and Release directories contain
    150 a manifest (.nmf) file that references the associated .nexe or .pexe files.
    151 For information about Native Client manifest files, see the :doc:`Technical
    152 Overview <../overview>`.
    153 
    154 For details on how to use ``make``, see the `GNU 'make' Manual
    155 <http://www.gnu.org/software/make/manual/make.html>`_. For details on how to
    156 use the SDK toolchain itself, see :doc:`Building Native Client Modules
    157 <../devguide/devcycle/building>`.
    158 
    159 .. _running_the_sdk_examples:
    160 
    161 Run the SDK examples
    162 --------------------
    163 
    164 To run the SDK examples, you can use the ``make run`` command::
    165 
    166   $ cd pepper_31/examples/api/core
    167   $ make run
    168 
    169 This will launch a local HTTP server which will serve the data for the
    170 example. It then launches Chrome with the address of this server, usually
    171 ``http://localhost:5103``. After you close Chrome, the local HTTP server is
    172 automatically shutdown.
    173 
    174 This command will try to find an executable named ``google-chrome`` in your
    175 ``PATH`` environment variable. If it can't, you'll get an error message like
    176 this::
    177 
    178   pepper_31/tools/common.mk:415: No valid Chrome found at CHROME_PATH=
    179   pepper_31/tools/common.mk:415: *** Set CHROME_PATH via an environment variable, or command-line..  Stop.
    180 
    181 Set the CHROME_PATH environment variable to the location of your Chrome
    182 executable.
    183 
    184 * On Windows:
    185 
    186   The default install location of Chrome is
    187   ``C:\Program Files (x86)\Google\Chrome\Application\chrome.exe`` for Chrome
    188   stable and
    189   ``C:\Users\<username>\AppData\Local\Google\Chrome SxS\Application\chrome.exe``
    190   for Chrome Canary; try looking in those directories first::
    191 
    192     > set CHROME_PATH=<Path to chrome.exe>
    193 
    194 * On Linux::
    195 
    196     $ export CHROME_PATH=<Path to google-chrome>
    197 
    198 * On Mac:
    199 
    200   The default install location of Chrome is
    201   ``/Applications/Google Chrome.app/Contents/MacOS/Google Chrome`` for
    202   Chrome Stable and
    203   ``Applications/Google Chrome Canary.app/Contents/MacOS/Google Chrome Canary``
    204   for Chrome Canary. Note that you have to reference the executable inside the
    205   application bundle, not the top-level ``.app`` directory::
    206 
    207     $ export CHROME_PATH=<Path to Google Chrome>
    208 
    209 You can run via a different toolchain or configuration by using the
    210 ``TOOLCHAIN`` and ``CONFIG`` parameters to make::
    211 
    212   $ make run TOOLCHAIN=pnacl CONFIG=Debug
    213 
    214 .. _run_sdk_examples_as_packaged:
    215 
    216 Run the SDK examples as packaged apps
    217 -------------------------------------
    218 
    219 Each example can also be launched as a packaged app. For more information about
    220 using Native Client for packaged apps, see :ref:`Packaged application
    221 <distributing_packaged>`.  For general information about packaged apps, see the
    222 `Chrome apps documentation </apps/about_apps>`_.
    223 
    224 Some Pepper features, such as TCP/UDP socket access, are only allowed in
    225 packaged apps. The examples that use these features must be run as packaged
    226 apps, by using the ``make run_package`` command::
    227 
    228   $ make run_package
    229 
    230 You can use ``TOOLCHAIN`` and ``CONFIG`` parameters as above to run with a
    231 different toolchain or configuration.
    232 
    233 
    234 .. _debugging_the_sdk_examples:
    235 
    236 Debugging the SDK examples
    237 --------------------------
    238 
    239 The NaCl SDK uses `GDB <https://www.gnu.org/software/gdb/>`_ to debug Native
    240 Client code. The SDK includes a prebuilt version of GDB that is compatible with
    241 NaCl code. To use it, run the ``make debug`` command from an example directory::
    242 
    243   $ make debug
    244 
    245 This will launch Chrome with the ``--enable-nacl-debug`` flag set. This flag
    246 will cause Chrome to pause when a NaCl module is first loaded, waiting for a
    247 connection from gdb. The ``make debug`` command also simultaneously launches
    248 GDB and loads the symbols for that NEXE. To connect GDB to Chrome, in the GDB
    249 console, type::
    250 
    251   (gdb) target remote :4014
    252 
    253 This tells GDB to connect to a TCP port on ``localhost:4014``--the port that
    254 Chrome is listening on. GDB will respond::
    255 
    256   Remote debugging using :4014
    257   0x000000000fa00080 in ?? ()
    258 
    259 At this point, you can use the standard GDB commands to debug your NaCl module.
    260 The most common commands you will use to debug are ``continue``, ``step``,
    261 ``next``, ``break`` and ``backtrace``. See :doc:`Debugging
    262 <../devguide/devcycle/debugging>` for more information about debugging a Native Client
    263 application.
    264 
    265 
    266 .. |menu-icon| image:: /images/menu-icon.png
    267 .. |gear-icon| image:: /images/gear-icon.png
    268