A small shell script to fetch code from git upstreams in all directories

run-git-fetch.sh

#! /bin/bash

# find . -maxdepth 1 -type d \( ! -name . \) -print0 | xargs -0 -L1 /path/to/run-git-fetch.sh

fetch_file=".git-fetch"

echo "Working in $1"
cd "$1" || exit

fetch_upstream_and_merge()
{
    echo "Running git fetch origin in this dir"
    if git fetch origin 2> /dev/null;
    then
        touch $fetch_file
        curr_branch="$(git branch | grep \* | cut -f2 -d' ')"
        echo "Trying to merge origin/$curr_branch into current branch."
        if [[ "$(git diff)" ]]
        then
            echo "Working tree is not clean, not doing anything."
        else
            git merge origin/"$curr_branch" && echo "Local branch $curr_branch is now up-to-date."
        fi
    else
        echo "git fetch failed, not doing anything."
    fi
}

if [ -e $fetch_file ]
then
    echo "Fetch File exists in this dir"
    current_time_in_secs="$(date +%s)";
    # Where am I? Stat works differently on Linux and Mac :(
    machine_info="$(uname -s)"
    case "$machine_info" in
        Linux*)     fetch_file_last_modified=$(stat -c "%Y" $fetch_file);;
        Darwin*)    fetch_file_last_modified=$(stat -f "%m" $fetch_file);;
        # Unknown Machine, go with Linux default
        *)          fetch_file_last_modified=$(stat -c "%Y" $fetch_file)
    esac

    # If we ran a git-fetch less than 5 hours ago, don't do anything.
    if [ $((current_time_in_secs - fetch_file_last_modified)) -gt 18000 ]
    then
        fetch_upstream_and_merge
    else
        echo "We have run git-fetch recently. Skipping"
    fi
else
    echo "Fetch File does not exist in this dir."
    fetch_upstream_and_merge
fi