From 50f03f595092b2976f263592ee8cfef0aa02258c Mon Sep 17 00:00:00 2001
From: Diederik de Groot <ddegroot@talon.nl>
Date: Fri, 21 Apr 2017 16:39:03 +0200
Subject: [PATCH] Enh: scripts/MakeHeader script

Only write a new .h file if something changed for the header file being created.
This prevents a lot of recompilation during development
---
 scripts/MakeHeader.py | 57 +++++++++++++++++++++++++------------------
 1 file changed, 33 insertions(+), 24 deletions(-)

diff --git a/scripts/MakeHeader.py b/scripts/MakeHeader.py
index bcf1005a..a9a5f205 100755
--- a/scripts/MakeHeader.py
+++ b/scripts/MakeHeader.py
@@ -1,6 +1,9 @@
 #!/usr/bin/env python
-
 import os, sys, string
+try:
+   from cStringIO import StringIO
+except:
+   from StringIO import StringIO
 
 ANY=1
 COPY=2
@@ -13,23 +16,15 @@ static = 0
 file = open(sys.argv[1])
 name = sys.argv[1][:-2]
 
-out = open(name + ".h", "w")
-class writer:
-   def __init__(self, file):
-      self.file = file
-   def write(self, text):
-      self.file.write(text + "\n")
-out = writer(out)
-
-print("Generating "+name+".h")
+out = StringIO()
 
 selfheader = '#include "' + name + '.h"'
 
-out.write( "/* Do not edit this file. It was automatically generated. */" )
-out.write( "" )
+out.write( "/* Do not edit this file. It was automatically generated. */\n" )
+out.write( "\n" )
 
-out.write( "#ifndef HEADER_" + os.path.basename(name) )
-out.write( "#define HEADER_" + os.path.basename(name) )
+out.write( "#ifndef HEADER_" + os.path.basename(name) + "\n")
+out.write( "#define HEADER_" + os.path.basename(name) + "\n")
 is_blank = False
 for line in file.readlines():
    line = line[:-1]
@@ -41,7 +36,7 @@ for line in file.readlines():
       elif line.find("#include") == 0:
          pass
       elif line.find("htop - ") == 0 and line[-2:] == ".c":
-         out.write(line[:-2] + ".h")
+         out.write(line[:-2] + ".h\n")
       elif line.find("static ") != -1:
          if line[-1] == "{":
             state = SKIP
@@ -52,31 +47,31 @@ for line in file.readlines():
          static = 0
          equals = line.find(" = ")
          if line[-3:] == "= {":
-            out.write( "extern " + line[:-4] + ";" )
+            out.write( "extern " + line[:-4] + ";\n" )
             state = SKIP
          elif equals != -1:
-            out.write("extern " + line[:equals] + ";" )
+            out.write("extern " + line[:equals] + ";\n" )
          elif line.startswith("typedef struct"):
             state = SKIP
          elif line[-1] == "{":
-            out.write( line[:-2].replace("inline", "extern") + ";" )
+            out.write( line[:-2].replace("inline", "extern") + ";\n" )
             state = SKIP
          else:
-            out.write( line )
+            out.write( line + "\n")
          is_blank = False
       elif line == "":
          if not is_blank:
-            out.write( line )
+            out.write( line + "\n")
          is_blank = True
       else:
-         out.write( line )
+         out.write( line  + "\n")
          is_blank = False
    elif state == COPY:
       is_blank = False
       if line == "}*/":
          state = ANY
       else:
-         out.write( line )
+         out.write( line + "\n")
    elif state == SKIP:
       is_blank = False
       if len(line) >= 1 and line[0] == "}":
@@ -89,5 +84,19 @@ for line in file.readlines():
       is_blank = False
       state = ANY
 
-out.write( "" )
-out.write( "#endif" )
+out.write( "\n" )
+out.write( "#endif\n" )
+
+# only write a new .h file if something changed.
+# This prevents a lot of recompilation during development
+out.seek(0)
+try:
+   with open(name + ".h", "r") as orig:
+      origcontents = orig.readlines()
+except:
+   origcontents = ""
+if origcontents != out.readlines():
+   with open(name + ".h", "w") as new:
+      print("Writing "+name+".h")
+      new.write(out.getvalue())
+out.close()