Add Ionut's --include-dir and -C option support

fileutil.cc

@@ -33,6 +33,7 @@
 
 #include "log.h"
 #include "strutil.h"
+#include "flags.h"
 
 bool Exists(StringPiece filename) {
   CHECK(filename.size() < PATH_MAX);
@@ -174,6 +175,17 @@ class GlobCache {
       } else {
         if (Exists(pat))
           files->push_back(pat);
+        else {
+          for (auto inc_path : g_flags.include_dirs) {
+            auto to_check = (inc_path + '/' + pat);
+            LOG("searching for %s in : %s", pat, inc_path.c_str());
+            LOG("checking for Exists(|%s|)", to_check.c_str());
+            if (Exists(to_check.c_str())) {
+              LOG("found %s in : %s", pat, inc_path.c_str());
+              files->push_back(to_check);
+            }
+          }
+        }
       }
     }
     *files = p.first->second;

flags.cc

@@ -70,6 +70,9 @@ void Flags::Parse(int argc, char** argv) {
       should_propagate = false;
     } else if (!strcmp(arg, "-c")) {
       is_syntax_check_only = true;
+    } else if (!strcmp(arg, "-C")) {
+      if (chdir(argv[++i]) != 0)
+        PERROR("chdir failed");
     } else if (!strcmp(arg, "-i")) {
       is_dry_run = true;
     } else if (!strcmp(arg, "-s")) {
@@ -159,6 +162,8 @@ void Flags::Parse(int argc, char** argv) {
     } else if (ParseCommandLineOptionWithArg("--writable", argv, &i,
                                              &writable_str)) {
       writable.push_back(writable_str);
+    } else if (!strncmp(arg, "--include-dir=", 14)) {
+      include_dirs.push_back(string(&arg[14]));
     } else if (arg[0] == '-') {
       ERROR("Unknown flag: %s", arg);
     } else {

flags.h

@@ -68,6 +68,7 @@ struct Flags {
   vector<Symbol> targets;
   vector<StringPiece> cl_vars;
   vector<string> writable;
+  vector<string> include_dirs;
 
   void Parse(int argc, char** argv);
 };

testcase/include_dir.sh

@@ -0,0 +1,13 @@
+set -e
+
+mk="$@"
+
+cat <<EOF > Makefile
+test: test2
+	echo PASS
+include myfile.mk
+EOF
+
+mkdir -p test_dir
+echo -e "test2:\n\techo \$@" > test_dir/myfile.mk
+${mk} --include-dir=test_dir 2> /dev/null