flatc now creates the output directory if it doesn't exist yet.

Also cleaned up the general mkdir functionality.

Tested: on OS X.

Tested that a command line like: ./flatc -j -o foo/bar/baz tests/monster_test.fbs
generates files in foo/bar/baz/MyGame/Example/*.java which previously didn't exist.

Windows code was previously tested but has been moved, so needs to be tested again.

Change-Id: Iee943121b3be4f92961a3ec94c2cb578165f114a

include/flatbuffers/util.h

@@ -22,6 +22,11 @@
 #include <string>
 #include <sstream>
 #include <stdlib.h>
+#ifdef _WIN32
+#include <direct.h>
+#else
+#include <sys/stat.h>
+#endif
 
 namespace flatbuffers {
 
@@ -103,25 +108,40 @@ inline bool SaveFile(const char *name, const std::string &buf, bool binary) {
 static const char kPosixPathSeparator = '/';
 #ifdef _WIN32
 static const char kPathSeparator = '\\';
-static const char *PathSeparatorSet = "\\:/";
+static const char *PathSeparatorSet = "\\/";  // Intentionally no ':'
 #else
 static const char kPathSeparator = kPosixPathSeparator;
 static const char *PathSeparatorSet = "/";
 #endif // _WIN32
 
+// Returns the path with the extension, if any, removed.
 inline std::string StripExtension(const std::string &filepath) {
   size_t i = filepath.find_last_of(".");
   return i != std::string::npos ? filepath.substr(0, i) : filepath;
 }
 
+// Return the last component of the path, after the last separator.
 inline std::string StripPath(const std::string &filepath) {
   size_t i = filepath.find_last_of(PathSeparatorSet);
   return i != std::string::npos ? filepath.substr(i + 1) : filepath;
 }
 
+// Strip the last component of the path + separator.
 inline std::string StripFileName(const std::string &filepath) {
   size_t i = filepath.find_last_of(PathSeparatorSet);
-  return i != std::string::npos ? filepath.substr(0, i + 1) : "";
+  return i != std::string::npos ? filepath.substr(0, i) : "";
+}
+
+// This function ensure a directory exists, by recursively
+// creating dirs for any parts of the path that don't exist yet.
+inline void EnsureDirExists(const std::string &filepath) {
+  auto parent = StripFileName(filepath);
+  if (parent.length()) EnsureDirExists(parent);
+  #ifdef _WIN32
+    _mkdir(filepath.c_str())
+  #else
+    mkdir(filepath.c_str(), S_IRWXU|S_IRGRP|S_IXGRP);
+  #endif
 }
 
 // To and from UTF-8 unicode conversion functions

src/flatc.cpp

@@ -180,6 +180,7 @@ int main(int argc, const char *argv[]) {
 
       for (size_t i = 0; i < num_generators; ++i) {
         if (generator_enabled[i]) {
+          flatbuffers::EnsureDirExists(output_path);
           if (!generators[i].generate(parser, output_path, filebase, opts)) {
             Error((std::string("Unable to generate ") +
                    generators[i].name +

src/idl_gen_java.cpp

@@ -20,13 +20,6 @@
 #include "flatbuffers/idl.h"
 #include "flatbuffers/util.h"
 
-#ifdef _WIN32
-#include <direct.h>
-#define mkdir(n, m) _mkdir(n)
-#else
-#include <sys/stat.h>
-#endif
-
 namespace flatbuffers {
 namespace java {
 
@@ -351,8 +344,8 @@ static bool SaveClass(const Parser &parser, const Definition &def,
     }
     namespace_java += *it;
     namespace_dir += *it;
-    mkdir(namespace_dir.c_str(), S_IRWXU|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH);
   }
+  EnsureDirExists(namespace_dir);
 
   std::string code = "// automatically generated, do not modify\n\n";
   code += "package " + namespace_java + ";\n\n";

src/idl_parser.cpp

@@ -838,7 +838,8 @@ bool Parser::Parse(const char *source, const char *filepath) {
     while (IsNext(kTokenInclude)) {
       auto name = attribute_;
       Expect(kTokenStringConstant);
-      name = StripFileName(filepath) + name;
+      auto path = StripFileName(filepath);
+      if (path.length()) name = path + kPathSeparator + name;
       if (included_files_.find(name) == included_files_.end()) {
         // We found an include file that we have not parsed yet.
         // Load it and parse it.