fuzz: Introduce CallOneOf helper to replace switch-case

Can be reviewed with --ignore-all-space

1 files changed, 96 insertions, 99 deletions

diff --git a/src/test/fuzz/util.h b/src/test/fuzz/util.h
index 4e8e501895..b7cf395e76 100644
--- a/src/test/fuzz/util.h
+++ b/src/test/fuzz/util.h
@@ -36,6 +36,17 @@
 #include <string>
 #include <vector>
 
+template <typename... Callables>
+void CallOneOf(FuzzedDataProvider& fuzzed_data_provider, Callables... callables)
+{
+    constexpr size_t call_size{sizeof...(callables)};
+    static_assert(call_size >= 1);
+    const size_t call_index{fuzzed_data_provider.ConsumeIntegralInRange<size_t>(0, call_size - 1)};
+
+    size_t i{0};
+    return ((i++ == call_index ? callables() : void()), ...);
+}
+
 [[nodiscard]] inline std::vector<uint8_t> ConsumeRandomLengthByteVector(FuzzedDataProvider& fuzzed_data_provider, const size_t max_length = 4096) noexcept
 {
     const std::string s = fuzzed_data_provider.ConsumeRandomLengthString(max_length);
@@ -165,37 +176,31 @@ template <typename WeakEnumType, size_t size>
 [[nodiscard]] inline CTxDestination ConsumeTxDestination(FuzzedDataProvider& fuzzed_data_provider) noexcept
 {
     CTxDestination tx_destination;
-    switch (fuzzed_data_provider.ConsumeIntegralInRange<int>(0, 5)) {
-    case 0: {
-        tx_destination = CNoDestination{};
-        break;
-    }
-    case 1: {
-        tx_destination = PKHash{ConsumeUInt160(fuzzed_data_provider)};
-        break;
-    }
-    case 2: {
-        tx_destination = ScriptHash{ConsumeUInt160(fuzzed_data_provider)};
-        break;
-    }
-    case 3: {
-        tx_destination = WitnessV0ScriptHash{ConsumeUInt256(fuzzed_data_provider)};
-        break;
-    }
-    case 4: {
-        tx_destination = WitnessV0KeyHash{ConsumeUInt160(fuzzed_data_provider)};
-        break;
-    }
-    case 5: {
-        WitnessUnknown witness_unknown{};
-        witness_unknown.version = fuzzed_data_provider.ConsumeIntegral<int>();
-        const std::vector<uint8_t> witness_unknown_program_1 = fuzzed_data_provider.ConsumeBytes<uint8_t>(40);
-        witness_unknown.length = witness_unknown_program_1.size();
-        std::copy(witness_unknown_program_1.begin(), witness_unknown_program_1.end(), witness_unknown.program);
-        tx_destination = witness_unknown;
-        break;
-    }
-    }
+    CallOneOf(
+        fuzzed_data_provider,
+        [&] {
+            tx_destination = CNoDestination{};
+        },
+        [&] {
+            tx_destination = PKHash{ConsumeUInt160(fuzzed_data_provider)};
+        },
+        [&] {
+            tx_destination = ScriptHash{ConsumeUInt160(fuzzed_data_provider)};
+        },
+        [&] {
+            tx_destination = WitnessV0ScriptHash{ConsumeUInt256(fuzzed_data_provider)};
+        },
+        [&] {
+            tx_destination = WitnessV0KeyHash{ConsumeUInt160(fuzzed_data_provider)};
+        },
+        [&] {
+            WitnessUnknown witness_unknown{};
+            witness_unknown.version = fuzzed_data_provider.ConsumeIntegral<int>();
+            const std::vector<uint8_t> witness_unknown_program_1 = fuzzed_data_provider.ConsumeBytes<uint8_t>(40);
+            witness_unknown.length = witness_unknown_program_1.size();
+            std::copy(witness_unknown_program_1.begin(), witness_unknown_program_1.end(), witness_unknown.program);
+            tx_destination = witness_unknown;
+        });
     return tx_destination;
 }
 
@@ -354,32 +359,26 @@ public:
             return nullptr;
         }
         std::string mode;
-        switch (m_fuzzed_data_provider.ConsumeIntegralInRange<int>(0, 5)) {
-        case 0: {
-            mode = "r";
-            break;
-        }
-        case 1: {
-            mode = "r+";
-            break;
-        }
-        case 2: {
-            mode = "w";
-            break;
-        }
-        case 3: {
-            mode = "w+";
-            break;
-        }
-        case 4: {
-            mode = "a";
-            break;
-        }
-        case 5: {
-            mode = "a+";
-            break;
-        }
-        }
+        CallOneOf(
+            m_fuzzed_data_provider,
+            [&] {
+                mode = "r";
+            },
+            [&] {
+                mode = "r+";
+            },
+            [&] {
+                mode = "w";
+            },
+            [&] {
+                mode = "w+";
+            },
+            [&] {
+                mode = "a";
+            },
+            [&] {
+                mode = "a+";
+            });
 #ifdef _GNU_SOURCE
         const cookie_io_functions_t io_hooks = {
             FuzzedFileProvider::read,
@@ -477,66 +476,64 @@ public:
     return {fuzzed_data_provider};
 }
 
-#define WRITE_TO_STREAM_CASE(id, type, consume) \
-    case id: {                                  \
-        type o = consume;                       \
-        stream << o;                            \
-        break;                                  \
+#define WRITE_TO_STREAM_CASE(type, consume) \
+    [&] {                                   \
+        type o = consume;                   \
+        stream << o;                        \
     }
 template <typename Stream>
 void WriteToStream(FuzzedDataProvider& fuzzed_data_provider, Stream& stream) noexcept
 {
     while (fuzzed_data_provider.ConsumeBool()) {
         try {
-            switch (fuzzed_data_provider.ConsumeIntegralInRange<int>(0, 13)) {
-                WRITE_TO_STREAM_CASE(0, bool, fuzzed_data_provider.ConsumeBool())
-                WRITE_TO_STREAM_CASE(1, char, fuzzed_data_provider.ConsumeIntegral<char>())
-                WRITE_TO_STREAM_CASE(2, int8_t, fuzzed_data_provider.ConsumeIntegral<int8_t>())
-                WRITE_TO_STREAM_CASE(3, uint8_t, fuzzed_data_provider.ConsumeIntegral<uint8_t>())
-                WRITE_TO_STREAM_CASE(4, int16_t, fuzzed_data_provider.ConsumeIntegral<int16_t>())
-                WRITE_TO_STREAM_CASE(5, uint16_t, fuzzed_data_provider.ConsumeIntegral<uint16_t>())
-                WRITE_TO_STREAM_CASE(6, int32_t, fuzzed_data_provider.ConsumeIntegral<int32_t>())
-                WRITE_TO_STREAM_CASE(7, uint32_t, fuzzed_data_provider.ConsumeIntegral<uint32_t>())
-                WRITE_TO_STREAM_CASE(8, int64_t, fuzzed_data_provider.ConsumeIntegral<int64_t>())
-                WRITE_TO_STREAM_CASE(9, uint64_t, fuzzed_data_provider.ConsumeIntegral<uint64_t>())
-                WRITE_TO_STREAM_CASE(10, float, fuzzed_data_provider.ConsumeFloatingPoint<float>())
-                WRITE_TO_STREAM_CASE(11, double, fuzzed_data_provider.ConsumeFloatingPoint<double>())
-                WRITE_TO_STREAM_CASE(12, std::string, fuzzed_data_provider.ConsumeRandomLengthString(32))
-                WRITE_TO_STREAM_CASE(13, std::vector<char>, ConsumeRandomLengthIntegralVector<char>(fuzzed_data_provider))
-            }
+            CallOneOf(
+                fuzzed_data_provider,
+                WRITE_TO_STREAM_CASE(bool, fuzzed_data_provider.ConsumeBool()),
+                WRITE_TO_STREAM_CASE(char, fuzzed_data_provider.ConsumeIntegral<char>()),
+                WRITE_TO_STREAM_CASE(int8_t, fuzzed_data_provider.ConsumeIntegral<int8_t>()),
+                WRITE_TO_STREAM_CASE(uint8_t, fuzzed_data_provider.ConsumeIntegral<uint8_t>()),
+                WRITE_TO_STREAM_CASE(int16_t, fuzzed_data_provider.ConsumeIntegral<int16_t>()),
+                WRITE_TO_STREAM_CASE(uint16_t, fuzzed_data_provider.ConsumeIntegral<uint16_t>()),
+                WRITE_TO_STREAM_CASE(int32_t, fuzzed_data_provider.ConsumeIntegral<int32_t>()),
+                WRITE_TO_STREAM_CASE(uint32_t, fuzzed_data_provider.ConsumeIntegral<uint32_t>()),
+                WRITE_TO_STREAM_CASE(int64_t, fuzzed_data_provider.ConsumeIntegral<int64_t>()),
+                WRITE_TO_STREAM_CASE(uint64_t, fuzzed_data_provider.ConsumeIntegral<uint64_t>()),
+                WRITE_TO_STREAM_CASE(float, fuzzed_data_provider.ConsumeFloatingPoint<float>()),
+                WRITE_TO_STREAM_CASE(double, fuzzed_data_provider.ConsumeFloatingPoint<double>()),
+                WRITE_TO_STREAM_CASE(std::string, fuzzed_data_provider.ConsumeRandomLengthString(32)),
+                WRITE_TO_STREAM_CASE(std::vector<char>, ConsumeRandomLengthIntegralVector<char>(fuzzed_data_provider)));
         } catch (const std::ios_base::failure&) {
             break;
         }
     }
 }
 
-#define READ_FROM_STREAM_CASE(id, type) \
-    case id: {                          \
-        type o;                         \
-        stream >> o;                    \
-        break;                          \
+#define READ_FROM_STREAM_CASE(type) \
+    [&] {                           \
+        type o;                     \
+        stream >> o;                \
     }
 template <typename Stream>
 void ReadFromStream(FuzzedDataProvider& fuzzed_data_provider, Stream& stream) noexcept
 {
     while (fuzzed_data_provider.ConsumeBool()) {
         try {
-            switch (fuzzed_data_provider.ConsumeIntegralInRange<int>(0, 13)) {
-                READ_FROM_STREAM_CASE(0, bool)
-                READ_FROM_STREAM_CASE(1, char)
-                READ_FROM_STREAM_CASE(2, int8_t)
-                READ_FROM_STREAM_CASE(3, uint8_t)
-                READ_FROM_STREAM_CASE(4, int16_t)
-                READ_FROM_STREAM_CASE(5, uint16_t)
-                READ_FROM_STREAM_CASE(6, int32_t)
-                READ_FROM_STREAM_CASE(7, uint32_t)
-                READ_FROM_STREAM_CASE(8, int64_t)
-                READ_FROM_STREAM_CASE(9, uint64_t)
-                READ_FROM_STREAM_CASE(10, float)
-                READ_FROM_STREAM_CASE(11, double)
-                READ_FROM_STREAM_CASE(12, std::string)
-                READ_FROM_STREAM_CASE(13, std::vector<char>)
-            }
+            CallOneOf(
+                fuzzed_data_provider,
+                READ_FROM_STREAM_CASE(bool),
+                READ_FROM_STREAM_CASE(char),
+                READ_FROM_STREAM_CASE(int8_t),
+                READ_FROM_STREAM_CASE(uint8_t),
+                READ_FROM_STREAM_CASE(int16_t),
+                READ_FROM_STREAM_CASE(uint16_t),
+                READ_FROM_STREAM_CASE(int32_t),
+                READ_FROM_STREAM_CASE(uint32_t),
+                READ_FROM_STREAM_CASE(int64_t),
+                READ_FROM_STREAM_CASE(uint64_t),
+                READ_FROM_STREAM_CASE(float),
+                READ_FROM_STREAM_CASE(double),
+                READ_FROM_STREAM_CASE(std::string),
+                READ_FROM_STREAM_CASE(std::vector<char>));
         } catch (const std::ios_base::failure&) {
             break;
         }