| Index: misc/nacl/README |
| =================================================================== |
| --- a/misc/nacl/README |
| +++ b/misc/nacl/README |
| @@ -1,12 +1,14 @@ |
| Native Client |
| ============= |
| -This document outlines the basics of building and developing the Go runtime and programs in the Native Client (NaCl) environment. |
| +This document outlines the basics of building and developing the Go runtime and |
| +programs in the Native Client (NaCl) environment. |
| Go 1.3 supports three architectures |
| * nacl/386 which is standard 386. |
| - * nacl/amd64p32 which is a 64 bit architecture, where the address space is limited to a 4gb window. |
| + * nacl/amd64p32 which is a 64 bit architecture, where the address space is |
| + limited to a 4gb window. |
| * nacl/arm which is 32-bit ARMv7A architecture with 1GB address space. |
| For background it is recommended that you read http://golang.org/s/go13nacl. |
| @@ -14,34 +16,48 @@ |
| Prerequisites |
| ------------- |
| -Native Client programs are executed inside a sandbox, the NaCl runtime. This runtime must be installed before you can use NaCl programs. |
| +Native Client programs are executed inside a sandbox, the NaCl runtime. This |
| +runtime must be installed before you can use NaCl programs. |
| -The NaCl distribution comes with an installer which ensures you have access to the latest version of the runtime. The version tracks the Chrome numbering scheme. |
| +The NaCl distribution comes with an installer which ensures you have access to |
| +the latest version of the runtime. The version tracks the Chrome numbering |
| +scheme. |
| # Download NaCl |
| -Download nacl_sdk.zip file from https://developers.google.com/native-client/dev/sdk/download, and unpack it. I chose /opt/nacl_sdk |
| +Download nacl_sdk.zip file from |
| + https://developers.google.com/native-client/dev/sdk/download |
| +and unpack it. I chose /opt/nacl_sdk. |
| # Update |
| -The zip file contains a small skeleton that can be used to download the correct sdk. These are released every 6-8 weeks, in line with Chrome releases. |
| +The zip file contains a small skeleton that can be used to download the correct |
| +sdk. These are released every 6-8 weeks, in line with Chrome releases. |
| % cd /opt/nacl_sdk |
| % ./naclsdk update |
| -At this time pepper_33 is the stable version. If naclsdk downloads a later version, please adjust accordingly. As of June 2014, only the canary sdk provides support for nacl/arm. |
| +At this time pepper_34 is the stable version. If naclsdk downloads a later |
| +version, please adjust accordingly. As of June 2014, only the canary sdk |
| +provides support for nacl/arm. |
| -The cmd/go helper scripts expect that the runtime loaders, sel_ldr_{x86_{32,64},arm} and nacl_helper_bootstrap_arm are in your path. I find it easiest to make a symlink from the NaCl distribution to my $GOPATH/bin directory. |
| +The cmd/go helper scripts expect that the loaders sel_ldr_{x86_{32,64},arm} and |
| +nacl_helper_bootstrap_arm are in your path. I find it easiest to make a symlink |
| +from the NaCl distribution to my $GOPATH/bin directory. |
| - % ln -nfs /opt/nacl_sdk/pepper_33/tools/sel_ldr_x86_32 $GOPATH/bin/sel_ldr_x86_32 |
| - % ln -nfs /opt/nacl_sdk/pepper_33/tools/sel_ldr_x86_64 $GOPATH/bin/sel_ldr_x86_64 |
| + % ln -nfs /opt/nacl_sdk/pepper_34/tools/sel_ldr_x86_32 $GOPATH/bin/sel_ldr_x86_32 |
| + % ln -nfs /opt/nacl_sdk/pepper_34/tools/sel_ldr_x86_64 $GOPATH/bin/sel_ldr_x86_64 |
| % ln -nfs /opt/nacl_sdk/pepper_canary/tools/sel_ldr_arm $GOPATH/bin/sel_ldr_arm |
| - % ln -nfs /opt/nacl_sdk/pepper_canary/tools/nacl_helper_bootstrap_arm $GOPATH/bin/nacl_helper_bootstrap_arm # only required for NaCl/ARM. |
| + |
| +Additionally, for NaCl/ARM only: |
| + |
| + % ln -nfs /opt/nacl_sdk/pepper_canary/tools/nacl_helper_bootstrap_arm $GOPATH/bin/nacl_helper_bootstrap_arm |
| Support scripts |
| --------------- |
| -Symlink the two scripts in this directory into your $PATH, just as you did with NaCl sdk above. |
| +Symlink the two scripts in this directory into your $PATH, just as you did with |
| +NaCl sdk above. |
| % ln -nfs $GOROOT/go/misc/nacl/go_nacl_amd64p32_exec $GOPATH/bin/go_nacl_amd64p32_exec |
| % ln -nfs $GOROOT/go/misc/nacl/go_nacl_386_exec $GOPATH/bin/go_nacl_386_exec |
| @@ -50,18 +66,57 @@ |
| Building and testing |
| -------------------- |
| -Building for NaCl is similar to cross compiling for other platforms. However, as it is not possible to ever build in a `native` NaCl environment, the cmd/go tool has been enhanced to allow the full build, all.bash, to be executed, rather than just the compile stage, make.bash. |
| +Building for NaCl is similar to cross compiling for other platforms. However, |
| +as it is not possible to ever build in a `native` NaCl environment, the cmd/go |
| +tool has been enhanced to allow the full build, all.bash, to be executed, |
| +rather than just the compile stage, make.bash. |
| -The cmd/go tool knows that if GOOS is set to `nacl` it should not try to execute any binaries itself. Instead it passes their execution to a support script which sets up a Native Client environment and invokes the NaCl sandbox. |
| +The cmd/go tool knows that if GOOS is set to `nacl` it should not try to |
| +execute any binaries itself. Instead it passes their execution to a support |
| +script which sets up a Native Client environment and invokes the NaCl sandbox. |
| -The script's name has a special format, go_$GOOS_$GOARCH_exec, so cmd/go can find it. |
| +The script's name has a special format, go_$GOOS_$GOARCH_exec, so cmd/go can |
| +find it. |
| -In short, if the support scripts are in place, the cmd/go tool can be used as per normal. |
| +In short, if the support scripts are in place, the cmd/go tool can be used as |
| +per normal. |
| # Build and test Go for NaCl |
| -NaCl does not permit direct file system access. Instead, package syscall provides a simulated file system served by in-memory data. The script nacltest.bash is the NaCl equivalent of all.bash. It builds NaCl with an in-memory file system containing files needed for tests, and then it runs the tests. |
| +NaCl does not permit direct file system access. Instead, package syscall |
| +provides a simulated file system served by in-memory data. The script |
| +nacltest.bash is the NaCl equivalent of all.bash. It builds NaCl with an |
| +in-memory file system containing files needed for tests, and then it runs the |
| +tests. |
| % cd go/src |
| % env GOARCH=amd64p32 ./nacltest.bash |
| +Debugging |
| +--------- |
| + |
| +Assuming that you have built nacl/amd64p32 binary ./mybin and can run as: |
| + |
| + % sel_ldr_x86_64 -l /dev/null -S -e ./mybin |
| + |
| +Create the nacl manifest file mybin.manifest with the following contents: |
| + |
| + { "program": { "x86-64": { "url": "mybin" } } } |
| + |
| +url is the path to the binary relative to the manifest file. |
| +Then, run the program as: |
| + |
| + % sel_ldr_x86_64 -g -l /dev/null -S -e ./mybin |
| + |
| +The -g flag instructs the loader to stop at startup. Then, in another console: |
| + |
| + % /opt/nacl_sdk/pepper_34/toolchain/linux_x86_glibc/bin/x86_64-nacl-gdb |
| + % nacl-manifest mybin.manifest |
| + % target remote :4014 |
| + |
| +If you see that the program is stopped in _rt0_amd64p32_nacl, then symbols are |
| +loaded successfully and you can type 'c' to start the program. |
| +Next time you can automate it as: |
| + |
| + % /opt/nacl_sdk/pepper_34/toolchain/linux_x86_glibc/bin/x86_64-nacl-gdb \ |
| + -ex 'nacl-manifest mybin.manifest' -ex 'target remote :4014' |
