Index: tools/clang-format/ClangFormat.cpp
===================================================================
--- tools/clang-format/ClangFormat.cpp
+++ tools/clang-format/ClangFormat.cpp
@@ -22,6 +22,7 @@
 #include "clang/Rewrite/Core/Rewriter.h"
 #include "llvm/Support/CommandLine.h"
 #include "llvm/Support/FileSystem.h"
+#include "llvm/Support/Regex.h"
 #include "llvm/Support/Signals.h"
 
 using namespace llvm;
@@ -51,32 +52,32 @@
                      "Can only be used with one input file."),
             cl::cat(ClangFormatCategory));
 static cl::list<std::string>
-LineRanges("lines", cl::desc("<start line>:<end line> - format a range of\n"
-                             "lines (both 1-based).\n"
-                             "Multiple ranges can be formatted by specifying\n"
-                             "several -lines arguments.\n"
-                             "Can't be used with -offset and -length.\n"
-                             "Can only be used with one input file."),
-           cl::cat(ClangFormatCategory));
+    LineRanges("lines",
+               cl::desc("<start line>:<end line> - format a range of\n"
+                        "lines (both 1-based).\n"
+                        "Multiple ranges can be formatted by specifying\n"
+                        "several -lines arguments.\n"
+                        "Can't be used with -offset and -length.\n"
+                        "Can only be used with one input file."),
+               cl::cat(ClangFormatCategory));
 static cl::opt<std::string>
-    Style("style",
-          cl::desc(clang::format::StyleOptionHelpDescription),
+    Style("style", cl::desc(clang::format::StyleOptionHelpDescription),
           cl::init("file"), cl::cat(ClangFormatCategory));
 static cl::opt<std::string>
-FallbackStyle("fallback-style",
-              cl::desc("The name of the predefined style used as a\n"
-                       "fallback in case clang-format is invoked with\n"
-                       "-style=file, but can not find the .clang-format\n"
-                       "file to use.\n"
-                       "Use -fallback-style=none to skip formatting."),
-              cl::init("LLVM"), cl::cat(ClangFormatCategory));
+    FallbackStyle("fallback-style",
+                  cl::desc("The name of the predefined style used as a\n"
+                           "fallback in case clang-format is invoked with\n"
+                           "-style=file, but can not find the .clang-format\n"
+                           "file to use.\n"
+                           "Use -fallback-style=none to skip formatting."),
+                  cl::init("LLVM"), cl::cat(ClangFormatCategory));
 
-static cl::opt<std::string>
-AssumeFileName("assume-filename",
-               cl::desc("When reading from stdin, clang-format assumes this\n"
-                        "filename to look for a style config file (with\n"
-                        "-style=file) and to determine the language."),
-               cl::init("<stdin>"), cl::cat(ClangFormatCategory));
+static cl::opt<std::string> AssumeFileName(
+    "assume-filename",
+    cl::desc("When reading from stdin, clang-format assumes this\n"
+             "filename to look for a style config file (with\n"
+             "-style=file) and to determine the language."),
+    cl::init("<stdin>"), cl::cat(ClangFormatCategory));
 
 static cl::opt<bool> Inplace("i",
                              cl::desc("Inplace edit <file>s, if specified."),
@@ -91,9 +92,8 @@
                         "Can be used with -style option."),
                cl::cat(ClangFormatCategory));
 static cl::opt<unsigned>
-    Cursor("cursor",
-           cl::desc("The position of the cursor when invoking\n"
-                    "clang-format from an editor integration"),
+    Cursor("cursor", cl::desc("The position of the cursor when invoking\n"
+                              "clang-format from an editor integration"),
            cl::init(0), cl::cat(ClangFormatCategory));
 
 static cl::opt<bool> SortIncludes(
@@ -102,9 +102,23 @@
              "SortIncludes style flag"),
     cl::cat(ClangFormatCategory));
 
+static cl::opt<bool> Recursively("r",
+                                 cl::desc("Recursively search for <file>s."),
+                                 cl::cat(ClangFormatCategory));
+
 static cl::list<std::string> FileNames(cl::Positional, cl::desc("[<file> ...]"),
                                        cl::cat(ClangFormatCategory));
 
+static bool checkMultipleFilesPreconditions() {
+  if (!Offsets.empty() || !Lengths.empty() || !LineRanges.empty()) {
+    errs() << "error: -offset, -length and -lines can only be used for "
+              "single file.\n";
+    return true;
+  }
+
+  return false;
+}
+
 namespace clang {
 namespace format {
 
@@ -307,9 +321,50 @@
   return false;
 }
 
-}  // namespace format
-}  // namespace clang
+static bool formatRecusively() {
+  if (checkMultipleFilesPreconditions()) {
+    return false;
+  }
 
+  std::vector<std::string> files;
+
+  for (unsigned i = 0; i < FileNames.size(); ++i) {
+    SmallVector<char, 256> currentPath;
+    std::error_code ec;
+    llvm::sys::fs::file_status fileStatus;
+    llvm::sys::fs::current_path(currentPath);
+
+    for (llvm::sys::fs::recursive_directory_iterator I(currentPath, ec), E;
+         I != E; I.increment(ec)) {
+      if (ec) {
+        errs() << "error: error wile recursive files formatting. Error code: "
+               << ec.value();
+        return true;
+      }
+
+      Regex regex(FileNames[i]);
+
+      I->status(fileStatus);
+
+      if (fileStatus.type() == llvm::sys::fs::file_type::regular_file &&
+          regex.match(I->path())) {
+        files.push_back(I->path());
+      }
+    }
+  }
+
+  bool Error = false;
+
+  for (unsigned i = 0; i < files.size(); ++i) {
+    Error |= clang::format::format(files[i]);
+  }
+
+  return Error;
+}
+
+} // namespace format
+} // namespace clang
+
 static void PrintVersion() {
   raw_ostream &OS = outs();
   OS << clang::getClangToolFullVersion("clang-format") << '\n';
@@ -342,6 +397,10 @@
     return 0;
   }
 
+  if (Recursively) {
+    return clang::format::formatRecusively();
+  }
+
   bool Error = false;
   switch (FileNames.size()) {
   case 0:
@@ -351,15 +410,13 @@
     Error = clang::format::format(FileNames[0]);
     break;
   default:
-    if (!Offsets.empty() || !Lengths.empty() || !LineRanges.empty()) {
-      errs() << "error: -offset, -length and -lines can only be used for "
-                "single file.\n";
+    if (checkMultipleFilesPreconditions()) {
       return 1;
     }
     for (unsigned i = 0; i < FileNames.size(); ++i)
       Error |= clang::format::format(FileNames[i]);
+
     break;
   }
   return Error ? 1 : 0;
 }
-