[PHP] Add support for PHP7.

PHP5's C extension API has changed substantially so you need to use
-php7 to specify you want PHP7 compatible wrappers.
Fixes https://github.com/swig/swig/issues/571

Examples/php5/funcptr/Makefile

@@ -0,0 +1,20 @@
+TOP        = ../..
+SWIGEXE    = $(TOP)/../swig
+SWIG_LIB_DIR = $(TOP)/../$(TOP_BUILDDIR_TO_TOP_SRCDIR)Lib
+SRCS       = example.c
+TARGET     = example
+INTERFACE  = example.i
+LIBS       =
+SWIGOPT    =
+
+check: build
+	$(MAKE) -f $(TOP)/Makefile SRCDIR='$(SRCDIR)' php_run
+
+build:
+	$(MAKE) -f $(TOP)/Makefile SRCDIR='$(SRCDIR)' SRCS='$(SRCS)' \
+	SWIG_LIB_DIR='$(SWIG_LIB_DIR)' SWIGEXE='$(SWIGEXE)' \
+	SWIGOPT='$(SWIGOPT)' TARGET='$(TARGET)' INTERFACE='$(INTERFACE)' \
+	php
+
+clean:
+	$(MAKE) -f $(TOP)/Makefile SRCDIR='$(SRCDIR)' php_clean

Examples/php5/funcptr/example.c

@@ -0,0 +1,17 @@
+/* File : example.c */
+
+int do_op(int a, int b, int (*op)(int,int)) {
+  return (*op)(a,b);
+}
+
+int add(int a, int b) {
+  return a+b;
+}
+
+int sub(int a, int b) {
+  return a-b;
+}
+
+int mul(int a, int b) {
+  return a*b;
+}

Examples/php5/funcptr/example.h

@@ -0,0 +1,7 @@
+/* file: example.h */
+
+extern int do_op(int,int, int (*op)(int,int));
+extern int add(int,int);
+extern int sub(int,int);
+extern int mul(int,int);
+

Examples/php5/funcptr/example.i

@@ -0,0 +1,15 @@
+/* File : example.i */
+%module example
+%{
+#include "example.h"
+%}
+
+/* Wrap a function taking a pointer to a function */
+extern int  do_op(int a, int b, int (*op)(int, int));
+
+/* Now install a bunch of "ops" as constants */
+%constant int (*ADD)(int,int) = add;
+%constant int (*SUB)(int,int) = sub;
+%constant int (*MUL)(int,int) = mul;
+
+

Examples/php5/funcptr/runme.php

@@ -0,0 +1,24 @@
+<?php
+
+require "example.php";
+
+$a = 37;
+$b = 42;
+
+# Now call our C function with a bunch of callbacks
+
+print "Trying some C callback functions\n";
+print "    a        = $a\n";
+print "    b        = $b\n";
+print "    ADD(a,b) = ". do_op($a,$b,ADD)."\n";
+print "    SUB(a,b) = ". do_op($a,$b,SUB)."\n";
+print "    MUL(a,b) = ". do_op($a,$b,MUL)."\n";
+
+print "Here is what the C callback function objects look like in php\n";
+print "Using swig style string pointers as we need them registered as constants\n";
+print "    ADD      = " . ADD . "\n";
+print "    SUB      = " . SUB . "\n";
+print "    MUL      = " . MUL . "\n";
+
+?>
+