Modified version of Andy Casey's (@andycasey) post-commit hook to run latexdiff between different revisions of a latex draft (see http://astrowizici.st/blog/2013/10/04/publishing-with-git); works on Macs and when the paper is in a sub-directory of the main git repository.

post-commit

#!/bin/sh

# Post-commit hook for revision-awsm-ness

function gettempfilename()
{
    tempfilename=$1-$RANDOM$RANDOM.tex
    if [ -e $tempfilename ]
    then
        tempfilename=$(gettempfilename)
    fi
    echo $tempfilename
}

current_hash=$(git rev-parse HEAD)
current_dir=$(git diff-tree --no-commit-id --name-only -r $current_hash | xargs -I file dirname file)
num_revisions=$(git log --pretty=oneline $current_dir | grep -ic "revision [v\d+(?:\.\d+)*]")

# See if there are at least two revisions so that we can do a comparison
if [ $num_revisions -lt 2 ]
then
    exit
else

    # Check to see if the last named revision is actually the commit hash that just happened
    current_revision=$(git log --pretty=oneline $current_dir | grep -i "revision [v\d\.]" | grep -oEi "v\d+(?:\.\d+)" | head -n 1)
    most_recent_revision_hash=$(git log --pretty=oneline $current_dir | grep -i "revision [v\d+(?:\.\d+)*]" | head -n 1 | awk '{ print $1 }')

    # If the last commit wasn't the one that contained the most recent revision number, then there's nothing to do.
    if [[ "$current_hash" != "$most_recent_revision_hash" ]]; then
        exit
    fi

    previous_revision=$(git log --pretty=oneline $current_dir | grep -i "revision [v\d\.]" | grep -oEi "v\d+(?:\.\d+)" | sed -n 2p)
    previous_revision_hash=$(git log --pretty=oneline $current_dir | grep -i "revision [v\d+(?:\.\d+)*]" | sed -n 2p | awk '{ print $1 }')

    # Use the most edited tex file in this repository as the manuscript, unless the manuscript filename was specified as an argument
    most_edited_tex_file=$(git log --pretty=format: --name-only $current_dir | sort | uniq -c | sort -rg | grep ".tex$" | head -n 1 | awk '{ print $2 }')
    manuscript_filename=${1:-$most_edited_tex_file}
    manuscript_filename_no_ext="${manuscript_filename%.*}"

    # If we can't find the manuscript filename, then exit.
    if [ ! -f $manuscript_filename ]; then
        echo "Manuscript file $manuscript_filename does not exist."
    fi

    # Get the manuscript file associated with the previous revision hash
    previous_manuscript_filename=$(gettempfilename previous)
    git show $previous_revision_hash:$manuscript_filename > $previous_manuscript_filename

    # Use latexdiff to create a difference version
    diff_ms_no_file_ext="$manuscript_filename_no_ext-revisions-$current_revision"
    latexdiff $previous_manuscript_filename $manuscript_filename > $diff_ms_no_file_ext.tex
    rm -f $previous_manuscript_filename
    # mv this file to the original directory and cd into that directory
    diff_ms_dir=$(dirname $diff_ms_no_file_ext)
    diff_ms_no_file_ext_no_dir=$(basename $diff_ms_no_file_ext)
    cd $diff_ms_dir

    # Compile the difference file
    latex $diff_ms_no_file_ext_no_dir.tex > /dev/null 2>&1
    latex $diff_ms_no_file_ext_no_dir.tex > /dev/null 2>&1
    latex $diff_ms_no_file_ext_no_dir.tex > /dev/null 2>&1
    latex $diff_ms_no_file_ext_no_dir.tex > /dev/null 2>&1
    dvipdf $diff_ms_no_file_ext_no_dir.dvi > /dev/null 2>&1

    # Remove the intermediate files
    ls $diff_ms_no_file_ext_no_dir.* | grep -v pdf | xargs rm -f
    ls ${diff_ms_no_file_ext_no_dir}Notes.bib | grep -v pdf | xargs rm -f
    ls ${diff_ms_no_file_ext_no_dir}Notess.bib | grep -v pdf | xargs rm -f
    echo "Revisions to $manuscript_filename made between $previous_revision"\
         "and $current_revision are highlighted in $diff_ms_no_file_ext_no_dir.pdf"
fi
fi