all: misc updates

src/Makefile

@@ -22,7 +22,7 @@ endif
 # redirect to top-level CMake build
 #
 
-# note that top-level Makefile .DEFAULT_GOAL is build/release
+# NOTE that top-level Makefile .DEFAULT_GOAL is build/release
 .DEFAULT_GOAL = build/debug
 
 build/debug:   $(top_srcdir)/build/debug/upx

src/check/dt_check.cpp

@@ -541,18 +541,21 @@ void upx_compiler_sanity_check(void) noexcept {
 **************************************************************************/
 
 TEST_CASE("assert_noexcept") {
-    // just to make sure that our assert macros don't generate any warnings
+    // just to make sure that our own assert macros don't generate any warnings
     byte dummy = 0;
     byte *ptr1 = &dummy;
     const byte *const ptr2 = &dummy;
+    void *ptr3 = nullptr;
     assert(true);
     assert(1);
     assert(ptr1);
     assert(ptr2);
+    assert(!ptr3);
     assert_noexcept(true);
     assert_noexcept(1);
     assert_noexcept(ptr1);
     assert_noexcept(ptr2);
+    assert_noexcept(!ptr3);
 }
 
 TEST_CASE("noncopyable") {

src/conf.h

@@ -317,6 +317,7 @@ typedef upx_int64_t upx_off_t;
 #  define attribute_format(a,b) /*empty*/
 #endif
 
+// for no-op debug output
 inline void NO_printf(const char *, ...) attribute_format(1, 2);
 inline void NO_fprintf(FILE *, const char *, ...) attribute_format(2, 3);
 inline void NO_printf(const char *, ...) {}

src/headers.h

@@ -30,6 +30,7 @@
 #error "C++17 is required"
 #endif
 
+// sanity check
 #if defined(__ILP32) || defined(__ILP32__)
 static_assert(sizeof(int) == 4);
 static_assert(sizeof(long) == 4);

src/packer.h

@@ -288,7 +288,7 @@ protected:
     template <class T>
     static inline constexpr bool is_te16_type = is_same_any_v<T, byte, upx_uint16_t, BE16, LE16>;
     template <class T>
-    static inline constexpr bool is_te32_type = is_same_any_v<T, byte, unsigned, BE32, LE32>;
+    static inline constexpr bool is_te32_type = is_same_any_v<T, byte, upx_uint32_t, BE32, LE32>;
     template <class T>
     static inline constexpr bool is_te64_type = is_same_any_v<T, byte, upx_uint64_t, BE64, LE64>;
 

src/util/xspan.cpp

@@ -33,7 +33,7 @@ XSPAN_NAMESPACE_BEGIN
 // debugging stats
 struct XSpanStats {
     upx_std_atomic(size_t) check_range_counter;
-    // doctest checks will set these:
+    // these normally will be zero, but doctest checks will populate them
     upx_std_atomic(size_t) fail_nullptr;
     upx_std_atomic(size_t) fail_nullbase;
     upx_std_atomic(size_t) fail_not_same_base;
@@ -70,15 +70,15 @@ void xspan_fail_range_range() {
     throwCantPack("xspan_check_range: pointer out of range; take care!");
 }
 
-void xspan_check_range(const void *p, const void *base, ptrdiff_t size_in_bytes) {
-    if very_unlikely (p == nullptr)
+void xspan_check_range(const void *ptr, const void *base, ptrdiff_t size_in_bytes) {
+    xspan_stats.check_range_counter += 1;
+    if very_unlikely (ptr == nullptr)
         xspan_fail_range_nullptr();
     if very_unlikely (base == nullptr)
         xspan_fail_range_nullbase();
-    ptrdiff_t off = (const charptr) p - (const charptr) base;
+    ptrdiff_t off = (const charptr) ptr - (const charptr) base;
     if very_unlikely (off < 0 || off > size_in_bytes || size_in_bytes > UPX_RSIZE_MAX)
         xspan_fail_range_range();
-    xspan_stats.check_range_counter += 1;
     NO_fprintf(stderr, "xspan_check_range done\n");
 }
 

src/util/xspan.h

@@ -43,7 +43,7 @@
 #define XSPAN_CONFIG_ENABLE_IMPLICIT_CONVERSION 0
 #endif
 // allow automatic conversion PtrOrSpanOrNull => PtrOrSpan => Span (with run-time checks)
-// choose between compile-time safety vs. possible run-time errors
+// choose between compile-time safety vs. possible run-time exceptions
 #ifndef XSPAN_CONFIG_ENABLE_SPAN_CONVERSION
 #define XSPAN_CONFIG_ENABLE_SPAN_CONVERSION 1
 #endif

src/util/xspan_impl.h

@@ -42,13 +42,13 @@
 XSPAN_NAMESPACE_BEGIN
 
 // HINT: set env-var "UPX_DEBUG_DOCTEST_DISABLE=1" for improved debugging experience
-noinline void xspan_fail_nullptr();
-noinline void xspan_fail_nullbase();
-noinline void xspan_fail_not_same_base();
-noinline void xspan_fail_range_nullptr();
-noinline void xspan_fail_range_nullbase();
-noinline void xspan_fail_range_range();
-void xspan_check_range(const void *p, const void *base, ptrdiff_t size_in_bytes);
+noinline void xspan_fail_nullptr(void);
+noinline void xspan_fail_nullbase(void);
+noinline void xspan_fail_not_same_base(void);
+noinline void xspan_fail_range_nullptr(void);
+noinline void xspan_fail_range_nullbase(void);
+noinline void xspan_fail_range_range(void);
+void xspan_check_range(const void *ptr, const void *base, ptrdiff_t size_in_bytes);
 
 // help constructor to distinguish between number of elements and bytes
 struct XSpanCount {

src/util/xspan_impl_common.h

@@ -113,6 +113,7 @@ forceinline ~CSelf() noexcept {}
 #endif
     noinline void invalidate() {
         assertInvariants();
+        // poison the pointer
         ptr = (pointer) (upx_uintptr_t) 16; // point to non-null invalid address
         // ptr = (pointer) (void *) &ptr; // point to self
         base = ptr;

src/util/xspan_impl_ptr.h

@@ -59,6 +59,8 @@ private:
 
 public:
 #if XSPAN_CONFIG_ENABLE_IMPLICIT_CONVERSION || 1
+    // Ptr always provides automatic conversion to underlying type because
+    // it has limited functionality
     operator pointer() const noexcept { return ptr; }
 #endif
 
@@ -75,6 +77,7 @@ public:
 #endif
     noinline void invalidate() {
         assertInvariants();
+        // poison the pointer
         ptr = (pointer) (upx_uintptr_t) 16; // point to non-null invalid address
         // ptr = (pointer) (void *) &ptr; // point to self
         assertInvariants();