From ab318200dbc6f594e3c6169c7ee8d8249d75dbe4 Mon Sep 17 00:00:00 2001
From: Max Kellermann <max@musicpd.org>
Date: Thu, 8 Oct 2020 20:13:57 +0200
Subject: [PATCH] config/{Data,Block}: use With() in GetUnsigned(),
 GetPositive()

---
 src/config/Block.cxx  | 19 ++-----------------
 src/config/Data.cxx   | 42 ++++++++++--------------------------------
 src/config/Parser.cxx | 33 +++++++++++++++++++++++++++++++++
 src/config/Parser.hxx | 18 ++++++++++++++++++
 4 files changed, 63 insertions(+), 49 deletions(-)

diff --git a/src/config/Block.cxx b/src/config/Block.cxx
index 82cca9d80..2c3da5ace 100644
--- a/src/config/Block.cxx
+++ b/src/config/Block.cxx
@@ -47,28 +47,13 @@ BlockParam::GetIntValue() const
 unsigned
 BlockParam::GetUnsignedValue() const
 {
-	const char *const s = value.c_str();
-	char *endptr;
-	unsigned long value2 = strtoul(s, &endptr, 0);
-	if (endptr == s || *endptr != 0)
-		throw FormatRuntimeError("Not a valid number in line %i", line);
-
-	return (unsigned)value2;
+	return With(ParseUnsigned);
 }
 
 unsigned
 BlockParam::GetPositiveValue() const
 {
-	const char *const s = value.c_str();
-	char *endptr;
-	unsigned long value2 = strtoul(s, &endptr, 0);
-	if (endptr == s || *endptr != 0)
-		throw FormatRuntimeError("Not a valid number in line %i", line);
-
-	if (value2 <= 0)
-		throw FormatRuntimeError("Number in line %i must be positive", line);
-
-	return (unsigned)value2;
+	return With(ParsePositive);
 }
 
 bool
diff --git a/src/config/Data.cxx b/src/config/Data.cxx
index 479b8fa6b..143ef5612 100644
--- a/src/config/Data.cxx
+++ b/src/config/Data.cxx
@@ -84,43 +84,21 @@ ConfigData::GetPath(ConfigOption option) const
 unsigned
 ConfigData::GetUnsigned(ConfigOption option, unsigned default_value) const
 {
-	const auto *param = GetParam(option);
-	long value;
-	char *endptr;
-
-	if (param == nullptr)
-		return default_value;
-
-	const char *const s = param->value.c_str();
-	value = strtol(s, &endptr, 0);
-	if (endptr == s || *endptr != 0 || value < 0)
-		throw FormatRuntimeError("Not a valid non-negative number in line %i",
-					 param->line);
-
-	return (unsigned)value;
+	return With(option, [default_value](const char *s){
+		return s != nullptr
+			? ParseUnsigned(s)
+			: default_value;
+	});
 }
 
 unsigned
 ConfigData::GetPositive(ConfigOption option, unsigned default_value) const
 {
-	const auto *param = GetParam(option);
-	long value;
-	char *endptr;
-
-	if (param == nullptr)
-		return default_value;
-
-	const char *const s = param->value.c_str();
-	value = strtol(s, &endptr, 0);
-	if (endptr == s || *endptr != 0)
-		throw FormatRuntimeError("Not a valid number in line %i",
-					 param->line);
-
-	if (value <= 0)
-		throw FormatRuntimeError("Not a positive number in line %i",
-					 param->line);
-
-	return (unsigned)value;
+	return With(option, [default_value](const char *s){
+		return s != nullptr
+			? ParsePositive(s)
+			: default_value;
+	});
 }
 
 bool
diff --git a/src/config/Parser.cxx b/src/config/Parser.cxx
index 1d79dca8e..89c3458c1 100644
--- a/src/config/Parser.cxx
+++ b/src/config/Parser.cxx
@@ -22,6 +22,8 @@
 #include "util/StringStrip.hxx"
 #include "util/StringUtil.hxx"
 
+#include <cstdlib>
+
 bool
 ParseBool(const char *value)
 {
@@ -37,6 +39,37 @@ ParseBool(const char *value)
 	throw FormatRuntimeError(R"(Not a valid boolean ("yes" or "no"): "%s")", value);
 }
 
+long
+ParseLong(const char *s)
+{
+	char *endptr;
+	long value = strtol(s, &endptr, 10);
+	if (endptr == s || *endptr != 0)
+		throw std::runtime_error("Failed to parse number");
+
+	return value;
+}
+
+unsigned
+ParseUnsigned(const char *s)
+{
+	auto value = ParseLong(s);
+	if (value < 0)
+		throw std::runtime_error("Value must not be negative");
+
+	return (unsigned)value;
+}
+
+unsigned
+ParsePositive(const char *s)
+{
+	auto value = ParseLong(s);
+	if (value <= 0)
+		throw std::runtime_error("Value must be positive");
+
+	return (unsigned)value;
+}
+
 template<size_t OPERAND>
 static size_t
 Multiply(size_t value)
diff --git a/src/config/Parser.hxx b/src/config/Parser.hxx
index 93fccaa53..b448709cd 100644
--- a/src/config/Parser.hxx
+++ b/src/config/Parser.hxx
@@ -28,6 +28,24 @@
 bool
 ParseBool(const char *value);
 
+/**
+ * Throws on error.
+ */
+long
+ParseLong(const char *s);
+
+/**
+ * Throws on error.
+ */
+unsigned
+ParseUnsigned(const char *s);
+
+/**
+ * Throws on error.
+ */
+unsigned
+ParsePositive(const char *s);
+
 /**
  * Parse a string as a byte size.
  *