pbx: Create pbx_include.c for management of 'struct ast_include'.

This changes context includes from a linked list to a vector, makes
'struct ast_include' opaque to pbx.c.

Although ast_walk_context_includes is maintained the procedure is no
longer efficient except for the first call (inc==NULL).  This
functionality is replaced by two new functions implemented by vector
macros.
* ast_context_includes_count (AST_VECTOR_SIZE)
* ast_context_includes_get (AST_VECTOR_GET)

As with ast_walk_context_includes callers of these functions are
expected to have locked contexts.  Only a few places in Asterisk walked
the includes, they have been converted to use the new functions.

const have been applied where possible to parameters for ast_include
functions.

Change-Id: Ib5c882e27cf96fb2aec67a39c18b4c71c9c83b60

main/pbx_include.c

@@ -0,0 +1,112 @@
+/*
+ * Asterisk -- An open source telephony toolkit.
+ *
+ * Copyright (C) 2016, CFWare, LLC
+ *
+ * Corey Farrell <git@cfware.com>
+ *
+ * See http://www.asterisk.org for more information about
+ * the Asterisk project. Please do not directly contact
+ * any of the maintainers of this project for assistance;
+ * the project provides a web site, mailing lists and IRC
+ * channels for your use.
+ *
+ * This program is free software, distributed under the terms of
+ * the GNU General Public License Version 2. See the LICENSE file
+ * at the top of the source tree.
+ */
+
+/*! \file
+ *
+ * \brief Dialplan context include routines.
+ *
+ * \author Corey Farrell <git@cfware.com>
+ */
+
+/*** MODULEINFO
+	<support_level>core</support_level>
+ ***/
+
+#include "asterisk.h"
+
+ASTERISK_REGISTER_FILE()
+
+#include "asterisk/_private.h"
+#include "asterisk/pbx.h"
+#include "pbx_private.h"
+
+/*! ast_include: include= support in extensions.conf */
+struct ast_include {
+	const char *name;
+	/*! Context to include */
+	const char *rname;
+	/*! Registrar */
+	const char *registrar;
+	/*! If time construct exists */
+	int hastime;
+	/*! time construct */
+	struct ast_timing timing;
+	char stuff[0];
+};
+
+const char *ast_get_include_name(const struct ast_include *inc)
+{
+	return inc ? inc->name : NULL;
+}
+
+const char *include_rname(const struct ast_include *inc)
+{
+	return inc ? inc->rname : NULL;
+}
+
+const char *ast_get_include_registrar(const struct ast_include *inc)
+{
+	return inc ? inc->registrar : NULL;
+}
+
+int include_valid(const struct ast_include *inc)
+{
+	if (!inc->hastime) {
+		return 1;
+	}
+
+	return ast_check_timing(&(inc->timing));
+}
+
+struct ast_include *include_alloc(const char *value, const char *registrar)
+{
+	struct ast_include *new_include;
+	char *c;
+	int valuebufsz = strlen(value) + 1;
+	char *p;
+
+	/* allocate new include structure ... */
+	new_include = ast_calloc(1, sizeof(*new_include) + (valuebufsz * 2));
+	if (!new_include) {
+		return NULL;
+	}
+
+	/* Fill in this structure. Use 'p' for assignments, as the fields
+	 * in the structure are 'const char *'
+	 */
+	p = new_include->stuff;
+	new_include->name = p;
+	strcpy(p, value);
+	p += valuebufsz;
+	new_include->rname = p;
+	strcpy(p, value);
+	/* Strip off timing info, and process if it is there */
+	if ((c = strchr(p, ',')) ) {
+		*c++ = '\0';
+		new_include->hastime = ast_build_timing(&(new_include->timing), c);
+	}
+	new_include->registrar = registrar;
+
+	return new_include;
+}
+
+void include_free(struct ast_include *inc)
+{
+	ast_destroy_timing(&(inc->timing));
+	ast_free(inc);
+}