[UCRT] Import Microsoft.Windows.SDK.CRTSource version 10.0.22621.3

Imported from https://www.nuget.org/packages/Microsoft.Windows.SDK.CRTSource/10.0.22621.3
License: MIT

sdk/lib/ucrt/stdlib/bsearch.cpp

@@ -0,0 +1,126 @@
+//
+// bsearch.cpp
+//
+//      Copyright (c) Microsoft Corporation. All rights reserved.
+//
+// Defines bsearch(), which performs a binary search over an array.
+//
+#include <corecrt_internal.h>
+#include <search.h>
+
+#ifdef _M_CEE
+    #define __fileDECL __clrcall
+#else
+    #define __fileDECL __cdecl
+#endif
+
+/***
+*char *bsearch() - do a binary search on an array
+*
+*Purpose:
+*   Does a binary search of a sorted array for a key.
+*
+*Entry:
+*   const char *key    - key to search for
+*   const char *base   - base of sorted array to search
+*   unsigned int num   - number of elements in array
+*   unsigned int width - number of bytes per element
+*   int (*compare)()   - pointer to function that compares two array
+*           elements, returning neg when #1 < #2, pos when #1 > #2, and
+*           0 when they are equal. Function is passed pointers to two
+*           array elements.
+*
+*Exit:
+*   if key is found:
+*           returns pointer to occurrence of key in array
+*   if key is not found:
+*           returns nullptr
+*
+*Exceptions:
+*   Input parameters are validated. Refer to the validation section of the function.
+*
+*******************************************************************************/
+
+#ifdef __USE_CONTEXT
+    #define __COMPARE(context, p1, p2) (*compare)(context, p1, p2)
+#else
+    #define __COMPARE(context, p1, p2) (*compare)(p1, p2)
+#endif
+
+#ifndef _M_CEE
+extern "C"
+#endif
+
+_CRT_SECURITYSAFECRITICAL_ATTRIBUTE
+#ifdef __USE_CONTEXT
+void* __fileDECL bsearch_s(
+    void const* const key,
+    void const* const base,
+    size_t            num,
+    size_t      const width,
+    int (__fileDECL* const compare)(void*, void const*, void const*),
+    void*       const context
+    )
+#else // __USE_CONTEXT
+void* __fileDECL bsearch(
+    void const* const key,
+    void const* const base,
+    size_t            num,
+    size_t      const width,
+    int (__fileDECL* const compare)(void const*, void const*)
+    )
+#endif // __USE_CONTEXT
+{
+    _VALIDATE_RETURN(base != nullptr || num == 0, EINVAL, nullptr);
+    _VALIDATE_RETURN(width > 0, EINVAL, nullptr);
+    _VALIDATE_RETURN(compare != nullptr, EINVAL, nullptr);
+
+    char const* lo = reinterpret_cast<char const*>(base);
+    char const* hi = reinterpret_cast<char const*>(base) + (num - 1) * width;
+
+    // Reentrancy diligence: Save (and unset) global-state mode to the stack before making callout to 'compare'
+    __crt_state_management::scoped_global_state_reset saved_state;
+
+    // We allow a nullptr key here because it breaks some older code and because
+    // we do not dereference this ourselves so we can't be sure that it's a
+    // problem for the comparison function
+
+    while (lo <= hi)
+    {
+        size_t const half = num / 2;
+        if (half != 0)
+        {
+            char const* const mid = lo + (num & 1 ? half : (half - 1)) * width;
+
+            int const result = __COMPARE(context, key, mid);
+            if (result == 0)
+            {
+                return const_cast<void*>(static_cast<void const*>(mid));
+            }
+            else if (result < 0)
+            {
+                hi = mid - width;
+                num = num & 1 ? half : half - 1;
+            }
+            else
+            {
+                lo = mid + width;
+                num = half;
+            }
+        }
+        else if (num != 0)
+        {
+            return __COMPARE(context, key, lo)
+                ? nullptr
+                : const_cast<void*>(static_cast<void const*>(lo));
+        }
+        else
+        {
+            break;
+        }
+    }
+
+    return nullptr;
+}
+
+#undef __COMPARE