Compiling and linking Helix Core Server applications

The following sections tell you how to build your application on the target platform.

To build p4api.cc, include clientapi.h, which includes all the necessary header files for the sample client application.

Additional script libraries for Helix Core extensions

To learn about this technology, see the Helix Core Extensions Developer Guide.

Name	Description
libp4script.a	For the code common to server and client
libp4script_c.a	For the client-side
libp4script_curl	If you already have a copy of curl, you can skip linking to this version
libp4script_sqlite	If you already have a copy of SQLite, you can skip linking to this version

Link order

The link libraries distributed with P4API must be linked explicitly in the following order:

	UNIX	Windows
1	libclient.a	libclient.lib
2	librpc.a	librpc.lib
3	libsupp.a	libsupp.lib

SSL support

P4API libraries must be linked against the OpenSSL libraries from http://www.openssl.org/.

OpenSSL Library Version

We recommend keeping current with the latest minor version matching the version referenced in the Helix C/C++ API file librpc.a (or librpc.lib on Windows). To see which version is referenced by the library, run the following command on UNIX variants or Macintosh:

strings librpc.a | grep ^OpenSSL

On Windows:

strings librpc.lib | findstr /B OpenSSL

This command will produce an output similar to the following:

OpenSSL 1.0.1p 9 Jul 2015

In this example, you would use the latest minor version of OpenSSL that matches version 1.0.1.

Link order for SSL support

To enable SSL support, link with the ssl and crypto libraries from OpenSSL. This results in the following link order:

• libclient.a
• librpc.a
• libsupp.a
• libssl.a
• libcrypto.a

On Windows, the ssl and crypto OpenSSL libraries are named ssleay32.lib and libeay32.lib respectively.

Compiler support

UNIX

For all UNIX platforms, you can use the gcc compiler to compile client applications with the Helix C/C++ API.

Note that clientapi.h includes stdhdrs.h, which might attempt to set platform-specific defines. To ensure these defines are set properly, compile with the -DOS_XXX flag, where XXX is the platform name as specified by Perforce. (Use p4 -V to display the platform name; for example, for LINUX52X86, specify -DOS_LINUX.)

Some platforms require extra link libraries for sockets. Solaris requires the following compiler flags:

-lsocket -lnsl

Linux

Some platforms require extra link libraries for runtime support. Linux requires the following compiler flag:

-lrt

Windows

Using Microsoft Visual Studio (VC++), compile your client application with the following flags:

/DOS_NT /MT /DCASE_INSENSITIVE

For debugging, compile with the /MTd flag for multithreading.
Do not compile with /MD or /MDd, because these flags can cause undefined behavior.

Link with the following libraries:

• libcmt.lib
• oldnames.lib
• kernel32.lib
• ws2_32.lib
• advapi32.lib

Sample Jamfile

The following example shows a Jamfile that can be used to build p4api.cc, a Helix Core Server application. (This example is in the api subdirectory.)

CFLAGS = -g -D_GNU_SOURCE ;
LINK = c ;OPTIM = ;
Main p4api : p4api.cc ;
ObjectHdrs p4api : api ;
LinkLibraries p4api : api/libclient.a api/librpc.a api/libsupp.a

For more about jam, see Building with Jam.

Sample Makefile

The following is a GNU make file for building p4api.cc, a Helix Core Server application. (The example assumes the API is installed in the api subdirectory.)

SOURCES = p4api.cc
INCLUDES = -Iapi
OBJECTS = ${SOURCES:.cc=.o}
LIBRARIES = api/libclient.a api/librpc.a api/libsupp.a
BINARY = p4api
RM = /bin/rm -f

C = c
CFLAGS = -c -g -D_GNU_SOURCE
LINK = c
LINKFLAGS =

.cc.o :
   ${C} ${CFLAGS} $< ${INCLUDES}

${BINARY} : ${OBJECTS}
   ${LINK} -o ${BINARY} ${OBJECTS} ${LIBRARIES}

clean :
   - ${RM} ${OBJECTS} ${BINARY}