pre-commit

#!/bin/bash
#
# Copyright thomas dot braun aeht virtuell minus zuhause dot de,  2013
#
# A hook script to check that the to-be-commited files are valid
# filenames on a windows platform.
# Sources:
# - http://stackoverflow.com/a/62888
# - http://msdn.microsoft.com/en-us/library/aa365247.aspx
#
# To enable this hook, rename this file to "pre-commit", move it to ".git/hook" and make it executable.

if git rev-parse --verify HEAD >/dev/null 2>&1
then
	against=HEAD
else
	# Initial commit: diff against an empty tree object
	against=
fi

enforcecompatiblefilenames=$(git config hooks.enforcecompatiblefilenames)

# Redirect output to stderr.
exec 1>&2

if test "$enforcecompatiblefilenames" != "true"
then
  exit 0
fi

git diff --cached --name-only --diff-filter=A -z $against | while IFS= read -r -d '' filename; do
  # Non-printable characters from ASCII range 0-31 
  nonprintablechars=$(echo -n "$filename" | LC_ALL=C tr -d '[ -~]' | wc -c)

  # Illegal characters: < > : " / \ | ? *
  # We don't test for / (forward slash) here as that is even on *nix not allowed in *filename*
  illegalchars=$(echo -n "$filename" | LC_ALL=C grep -E '(<|>|:|"|\\|\||\?|\*)' | wc -c)

  # Reserved names plus possible extension
  # CON, PRN, AUX, NUL, COM1, COM2, COM3, COM4, COM5, COM6, COM7, COM8, COM9, LPT1, LPT2, LPT3, LPT4, LPT5, LPT6, LPT7, LPT8, and LPT9
  reservednames=$(echo -n "$filename" | LC_ALL=C grep -i -E '(CON|PRN|AUX|NUL|COM1|COM2|COM3|COM4|COM5|COM6|COM7|COM8|COM9|LPT1|LPT2|LPT3|LPT4|LPT5|LPT6|LPT7|LPT8|LPT9).[a-z]{3}' | wc -c)

  # No trailing period or space
  trailingperiodorspace=$(echo -n "$filename" | LC_ALL=C grep -E '(\.| )$' | wc -c)

  # File name is all periods
  filenameallperiods=$(echo -n "$filename" | LC_ALL=C grep -E '^\.+$' | wc -c)

  # Check complete path length to be smaller than 260 characters
  # This test can not be really accurate as we don't know if PWD on the windows filesystem itself is not very long 
  absolutepathtoolong=0
  if test $(echo "$filename" | wc -c) -ge 260
  then
    absolutepathtoolong=1
  fi

  # debug output
  if test -n "$GIT_TRACE"
  then
    echo "File: ${filename}"
    echo nonprintablechars=$nonprintablechars
    echo illegalchars=$illegalchars
    echo reservednames=$reservednames
    echo trailingperiodorspace=$trailingperiodorspace
    echo filenameallperiods=$filenameallperiods
    echo absolutepathtoolong=$absolutepathtoolong
  fi

  if test $nonprintablechars -ne 0 \
     || test $illegalchars -ne 0 \
     || test $reservednames -ne 0 \
     || test $trailingperiodorspace -ne 0 \
     || test $filenameallperiods -ne 0 \
     || test $absolutepathtoolong -ne 0
  then
    echo "Error: Attempt to add a file name which is incompatible to windows file systems."
    echo
    echo "If you know what you are doing you can disable this"
    echo "check using:"
    echo
    echo "git config hooks.enforcecompatiblefilenames false"
    echo
    exit 1
  fi
done