1 files changed, 122 insertions, 0 deletions
diff --git a/contrib/llvm-project/clang/lib/Format/MatchFilePath.cpp b/contrib/llvm-project/clang/lib/Format/MatchFilePath.cpp
new file mode 100644
index 000000000000..412ee4954587
--- /dev/null
+++ b/contrib/llvm-project/clang/lib/Format/MatchFilePath.cpp
@@ -0,0 +1,122 @@
+//===--- MatchFilePath.cpp - Match file path with pattern -------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+///
+/// \file
+/// This file implements the functionality of matching a file path name to
+/// a pattern, similar to the POSIX fnmatch() function.
+///
+//===----------------------------------------------------------------------===//
+
+#include "MatchFilePath.h"
+
+using namespace llvm;
+
+namespace clang {
+namespace format {
+
+// Check whether `FilePath` matches `Pattern` based on POSIX (1003.1-2008)
+// 2.13.1, 2.13.2, and Rule 1 of 2.13.3.
+bool matchFilePath(StringRef Pattern, StringRef FilePath) {
+  assert(!Pattern.empty());
+  assert(!FilePath.empty());
+
+  // No match if `Pattern` ends with a non-meta character not equal to the last
+  // character of `FilePath`.
+  if (const auto C = Pattern.back(); !strchr("?*]", C) && C != FilePath.back())
+    return false;
+
+  constexpr auto Separator = '/';
+  const auto EOP = Pattern.size();  // End of `Pattern`.
+  const auto End = FilePath.size(); // End of `FilePath`.
+  unsigned I = 0;                   // Index to `Pattern`.
+
+  for (unsigned J = 0; J < End; ++J) {
+    if (I == EOP)
+      return false;
+
+    switch (const auto F = FilePath[J]; Pattern[I]) {
+    case '\\':
+      if (++I == EOP || F != Pattern[I])
+        return false;
+      break;
+    case '?':
+      if (F == Separator)
+        return false;
+      break;
+    case '*': {
+      while (++I < EOP && Pattern[I] == '*') { // Skip consecutive stars.
+      }
+      const auto K = FilePath.find(Separator, J); // Index of next `Separator`.
+      const bool NoMoreSeparatorsInFilePath = K == StringRef::npos;
+      if (I == EOP) // `Pattern` ends with a star.
+        return NoMoreSeparatorsInFilePath;
+      // `Pattern` ends with a lone backslash.
+      if (Pattern[I] == '\\' && ++I == EOP)
+        return false;
+      // The star is followed by a (possibly escaped) `Separator`.
+      if (Pattern[I] == Separator) {
+        if (NoMoreSeparatorsInFilePath)
+          return false;
+        J = K; // Skip to next `Separator` in `FilePath`.
+        break;
+      }
+      // Recurse.
+      for (auto Pat = Pattern.substr(I); J < End && FilePath[J] != Separator;
+           ++J) {
+        if (matchFilePath(Pat, FilePath.substr(J)))
+          return true;
+      }
+      return false;
+    }
+    case '[':
+      // Skip e.g. `[!]`.
+      if (I + 3 < EOP || (I + 3 == EOP && Pattern[I + 1] != '!')) {
+        // Skip unpaired `[`, brackets containing slashes, and `[]`.
+        if (const auto K = Pattern.find_first_of("]/", I + 1);
+            K != StringRef::npos && Pattern[K] == ']' && K > I + 1) {
+          if (F == Separator)
+            return false;
+          ++I; // After the `[`.
+          bool Negated = false;
+          if (Pattern[I] == '!') {
+            Negated = true;
+            ++I; // After the `!`.
+          }
+          bool Match = false;
+          do {
+            if (I + 2 < K && Pattern[I + 1] == '-') {
+              Match = Pattern[I] <= F && F <= Pattern[I + 2];
+              I += 3; // After the range, e.g. `A-Z`.
+            } else {
+              Match = F == Pattern[I++];
+            }
+          } while (!Match && I < K);
+          if (Negated ? Match : !Match)
+            return false;
+          I = K + 1; // After the `]`.
+          continue;
+        }
+      }
+      [[fallthrough]]; // Match `[` literally.
+    default:
+      if (F != Pattern[I])
+        return false;
+    }
+
+    ++I;
+  }
+
+  // Match trailing stars with null strings.
+  while (I < EOP && Pattern[I] == '*')
+    ++I;
+
+  return I == EOP;
+}
+
+} // namespace format
+} // namespace clang