From c8c546fe99a343c13c7c0b8f2e5e180c19831b43 Mon Sep 17 00:00:00 2001
From: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Date: Thu, 31 Jan 2019 23:36:04 +0200
Subject: cam: options: Add option type handling to options parser
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Extend the options parser with support for option types. All options
must now specify the type of their argument, and the parser
automatically parses the argument and handles errors internally.
Available types are none, integer or string.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
---
 src/cam/options.cpp | 133 ++++++++++++++++++++++++++++++++++++++++++++++++++--
 1 file changed, 128 insertions(+), 5 deletions(-)

(limited to 'src/cam/options.cpp')

diff --git a/src/cam/options.cpp b/src/cam/options.cpp
index c13022ce..204081f3 100644
--- a/src/cam/options.cpp
+++ b/src/cam/options.cpp
@@ -12,6 +12,30 @@
 
 #include "options.h"
 
+/* -----------------------------------------------------------------------------
+ * Option
+ */
+
+const char *Option::typeName() const
+{
+	switch (type) {
+	case OptionNone:
+		return "none";
+
+	case OptionInteger:
+		return "integer";
+
+	case OptionString:
+		return "string";
+	}
+
+	return "unknown";
+}
+
+/* -----------------------------------------------------------------------------
+ * OptionBase<T>
+ */
+
 template <typename T>
 bool OptionsBase<T>::valid() const
 {
@@ -25,11 +49,45 @@ bool OptionsBase<T>::isSet(const T &opt) const
 }
 
 template <typename T>
-const std::string &OptionsBase<T>::operator[](const T &opt) const
+const OptionValue &OptionsBase<T>::operator[](const T &opt) const
 {
 	return values_.find(opt)->second;
 }
 
+template <typename T>
+bool OptionsBase<T>::parseValue(const T &opt, const Option &option,
+				const char *optarg)
+{
+	OptionValue value;
+
+	switch (option.type) {
+	case OptionNone:
+		break;
+
+	case OptionInteger:
+		unsigned int integer;
+
+		if (optarg) {
+			char *endptr;
+			integer = strtoul(optarg, &endptr, 10);
+			if (*endptr != '\0')
+				return false;
+		} else {
+			integer = 0;
+		}
+
+		value = OptionValue(integer);
+		break;
+
+	case OptionString:
+		value = OptionValue(optarg ? optarg : "");
+		break;
+	}
+
+	values_[opt] = value;
+	return true;
+}
+
 template <typename T>
 void OptionsBase<T>::clear()
 {
@@ -38,8 +96,53 @@ void OptionsBase<T>::clear()
 
 template class OptionsBase<int>;
 
-bool OptionsParser::addOption(int opt, const char *help, const char *name,
-			      OptionArgument argument, const char *argumentName)
+/* -----------------------------------------------------------------------------
+ * OptionValue
+ */
+
+OptionValue::OptionValue()
+	: type_(OptionNone)
+{
+}
+
+OptionValue::OptionValue(int value)
+	: type_(OptionInteger), integer_(value)
+{
+}
+
+OptionValue::OptionValue(const char *value)
+	: type_(OptionString), string_(value)
+{
+}
+
+OptionValue::OptionValue(const std::string &value)
+	: type_(OptionString), string_(value)
+{
+}
+
+OptionValue::operator int() const
+{
+	if (type_ != OptionInteger)
+		return 0;
+
+	return integer_;
+}
+
+OptionValue::operator std::string() const
+{
+	if (type_ != OptionString)
+		return std::string();
+
+	return string_;
+}
+
+/* -----------------------------------------------------------------------------
+ * OptionsParser
+ */
+
+bool OptionsParser::addOption(int opt, OptionType type, const char *help,
+			      const char *name, OptionArgument argument,
+			      const char *argumentName)
 {
 	/*
 	 * Options must have at least a short or long name, and a text message.
@@ -56,7 +159,8 @@ bool OptionsParser::addOption(int opt, const char *help, const char *name,
 	if (optionsMap_.find(opt) != optionsMap_.end())
 		return false;
 
-	options_.push_back(Option({ opt, name, argument, argumentName, help }));
+	options_.push_back(Option({ opt, type, name, argument, argumentName,
+				    help }));
 	optionsMap_[opt] = &options_.back();
 	return true;
 }
@@ -126,7 +230,13 @@ OptionsParser::Options OptionsParser::parse(int argc, char **argv)
 			break;
 		}
 
-		options.values_[c] = optarg ? optarg : "";
+		const Option &option = *optionsMap_[c];
+		if (!options.parseValue(c, option, optarg)) {
+			parseValueError(option);
+			usage();
+			options.clear();
+			break;
+		}
 	}
 
 	return options;
@@ -193,3 +303,16 @@ void OptionsParser::usage()
 		}
 	}
 }
+
+void OptionsParser::parseValueError(const Option &option)
+{
+	std::string optionName;
+
+	if (option.name)
+		optionName = "--" + std::string(option.name);
+	else
+		optionName = "-" + static_cast<char>(option.opt);
+
+	std::cerr << "Can't parse " << option.typeName()
+		  << " argument for option " << optionName << std::endl;
+}
-- 
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