qcacmn: Add qdf_file and qdf_parse files to QDF

Add an QDF abstraction for reading a file. Also, add the first consumer,
qdf_ini_parse(), as well. This is pure parsing logic, which offloads the
actual content handling to the caller via callback functions.

Change-Id: Idfca74c5543a5b0da7ddd1bdc6e2ad2be59ed36b
CRs-Fixed: 2184463

qdf/inc/qdf_parse.h

@@ -0,0 +1,58 @@
+/*
+ * Copyright (c) 2018 The Linux Foundation. All rights reserved.
+ *
+ * Permission to use, copy, modify, and/or distribute this software for
+ * any purpose with or without fee is hereby granted, provided that the
+ * above copyright notice and this permission notice appear in all
+ * copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL
+ * WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE
+ * AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
+ * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
+ * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
+ * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+ * PERFORMANCE OF THIS SOFTWARE.
+ */
+
+/**
+ * DOC: Thin filesystem API abstractions
+ */
+
+#ifndef __QDF_PARSE_H
+#define __QDF_PARSE_H
+
+#include "qdf_status.h"
+
+/**
+ * cfg_ini_parse() - parse an ini file
+ * @ini_path: The full file path of the ini file to parse
+ * @item_cb: Ini item (key/value pair) handler callback function
+ *	Return QDF_STATUS_SUCCESS to continue parsing, else to abort
+ * @section_cb: Ini section header handler callback function
+ *	Return QDF_STATUS_SUCCESS to continue parsing, else to abort
+ *
+ * The *.ini file format is a simple format consiting of a list of key/value
+ * pairs (items), separated by an '=' character. Comments are initiated with
+ * a '#' character. Sections are also supported, using '[' and ']' around the
+ * section name. e.g.
+ *
+ *	# comments are started with a '#' character
+ *	# items are key/value string pairs, separated by the '=' character
+ *	someKey1=someValue1
+ *	someKey2=someValue2 # this is also a comment
+ *
+ *	# section headers are enclosed in square brackets
+ *	[some section header] # new section begins
+ *	someKey3=someValue3
+ *
+ * Return: QDF_STATUS
+ */
+QDF_STATUS
+qdf_ini_parse(const char *ini_path,
+	      QDF_STATUS (*item_cb)(const char *key, const char *value),
+	      QDF_STATUS (*section_cb)(const char *name));
+
+#endif /* __QDF_PARSE_H */
+