Update for Go 1.2 release. Add support for linking SWIG code directly

into executable, rather than using a shared library.
This commit is contained in:
Ian Lance Taylor 2013-12-16 19:50:17 -08:00
commit 1dca0af024
32 changed files with 385 additions and 371 deletions

View file

@ -55,7 +55,7 @@ there is no convenient way to call C++ code. SWIG fills this gap.
<p>
There are (at least) two different Go compilers. One is the gc
compiler, normally invoked under the names 6g, 8g, or 5g. The other
compiler, normally invoked under via the go tool. The other
is the gccgo compiler, which is a frontend to the gcc compiler suite.
The interface to C/C++ code is completely different for the two Go
compilers. SWIG supports both, selected by a command line option.
@ -80,7 +80,7 @@ code for gccgo, you should also use the <tt>-gccgo</tt> option.
<p>
These are the command line options for SWIG's GO module. They can
These are the command line options for SWIG's Go module. They can
also be seen by using:
</p>
@ -108,7 +108,7 @@ swig -go -help
<tr>
<td>-gccgo</td>
<td>Generate code for gccgo. The default is to generate code for
6g/8g/5g.</td>
the gc compiler.</td>
</tr>
<tr>
@ -117,13 +117,21 @@ swig -go -help
package name is the SWIG module name.</td>
</tr>
<tr>
<td>-use-shlib</td>
<td>Tell SWIG to emit code that uses a shared library. This is only
meaningful for the gc compiler, which needs to know at compile time
whether a shared library will be used.</td>
</tr>
<tr>
<td>-soname %lt;name%gt;</td>
<td>Set the runtime name of the shared library that the dynamic linker
should include at runtime. The default is the package name with
".so" appended. This is only used when generating code for
6g/8g/5g; when using gccgo, the equivalent name will be taken from
the <code>-soname</code> option passed to the linker.</td>
the gc compiler; when using gccgo, the equivalent name will be taken from
the <code>-soname</code> option passed to the linker. Using this
option implies the -use-shlib option.</td>
</tr>
<tr>
@ -165,25 +173,56 @@ may be helpful to include it in your code, compiled with the usual C
or C++ compiler.
<li>
If using the gc compiler, MODULE_gc.c will contain C code which should
be compiled with the C compiler distributed as part of the gc compiler: 6c, 8c,
or 5c. It should then be combined with the compiled MODULE.go using
gopack. This file will not be generated when using gccgo.
be compiled with the C compiler distributed as part of the gc
compiler. It should then be combined with the compiled MODULE.go
using gopack. This file will not be generated when using gccgo.
</ul>
<p>
A typical command sequence would look like this:
Most Go programs are built using the go tool. The go tool has limited
support for SWIG. To use it, put your SWIG interface into a file with
the extension .swig, or, if you are wrapping C++ code, .swigcxx. Put
that file in a GOPATH/src directory as usual for Go sources. Put
other interface code in the same directory with extensions of .c and
.cxx. The go build command and go install commands will automatically
run SWIG for you and will build the interface code.
</p>
<p>
You can also use SWIG directly yourself. When using the gc compiler
version 1.2 or later, or when using gccgo, the code generated by SWIG
can be linked directly into the Go program. A typical command
sequence when using the gc compiler would look like this:
</p>
<div class="code"><pre>
% swig -go example.i
% gcc -c code.c # The C library being wrapped.
% gcc -c example_wrap.c
% go tool 6g example.go
% go tool 6c example_gc.c
% go tool pack grc example.a example.6 example_gc.6 code.o example_wrap.o
% go tool 6g main.go
% go tool 6l main.6
</pre></div>
<p>
You can also put the wrapped code into a shared library, and when
using the gc compiler before version 1.2 this is the only supported
option. A typical command sequence for this approach would look like
this:
</p>
<div class="code"><pre>
% swig -go -use-shlib example.i
% gcc -c -fpic example.c
% gcc -c -fpic example_wrap.c
% gcc -shared example.o example_wrap.o -o example.so
% 6g example.go
% 6c example_gc.c
% gopack grc example.a example.6 example_gc.6
% 6g main.go # your code, not generated by SWIG
% 6l main.6
% go tool 6g example.go
% go tool 6c example_gc.c
% go tool pack grc example.a example.6 example_gc.6
% go tool 6g main.go # your code, not generated by SWIG
% go tool 6l main.6
</pre></div>
<H2><a name="Go_basic_tour"></a>22.3 A tour of basic C/C++ wrapping</H2>