libbtrfsutil: update btrfsutil long description

Provide at least basic description of the library for pypi.org main
page. It's for libbtrfsutil that mentions the C and python usage.

[ ci skip ]

Issue: kdave#310
Signed-off-by: David Sterba <[email protected]>

libbtrfsutil/python/.gitignore

@@ -5,3 +5,4 @@ __pycache__
 /build
 /constants.c
 /dist
+/pypi-README.md

libbtrfsutil/python/setup.py

@@ -68,8 +68,26 @@ def gen_constants():
 """)
 
 
+def read_readme():
+    # FIXME: hackish, needs to be run twice to work
+    if not os.path.exists('pypi-README.md'):
+        copy_readme()
+        raise Exception("Copied ../README.md to pypi-README.md, run again")
+    with open('pypi-README.md', 'r') as f:
+        desc = f.read()
+    return desc
+
+
+def copy_readme():
+    with open('../README.md', 'r') as f:
+        desc = f.read()
+    with open('pypi-README.md', 'w') as f:
+        f.write(desc)
+
+
 class my_build_ext(build_ext):
     def run(self):
+        open(os.path.join(os.path.dirname(__file__), "pypi-README.md"), 'r')
         # Running dist outside of git
         if not os.path.exists('../btrfsutil.h'):
             # But no generated constants.c found
@@ -84,6 +102,19 @@ def run(self):
                 except OSError:
                     pass
                 raise e
+        if not os.path.exists('../README.md'):
+            # But no generated constants.c found
+            if not os.path.exists('pypi-README.md'):
+                raise Exception("The temporary description file pypi-README.md not found, please fix manually")
+        elif out_of_date(['../README.md'], 'pypi-README.md'):
+            try:
+                copy_readme()
+            except Exception as e:
+                try:
+                    os.remove('pypi-README.md')
+                except OSError:
+                    pass
+                raise e
         super().run()
 
 
@@ -111,6 +142,8 @@ def run(self):
     #version=get_version(),
     version='6.11',
     description='Library for managing Btrfs filesystems',
+    long_description=read_readme(),
+    long_description_content_type='text/markdown',
     url='https://github.com/kdave/btrfs-progs',
     license='LGPLv2+',
     cmdclass={'build_ext': my_build_ext},