Issue 1089: Move the script generate_patches.sh from lipcap to meta tools

tools/generate_patches.sh

@@ -0,0 +1,167 @@
+#!/usr/bin/env bash
+
+echo_error()
+{
+    echo "ERROR: $1"
+}
+
+echo_usage()
+{
+    echo "Usage: ./generate_patches.sh -p <port-dir absolute path> -s <src-dir absolute path> [optional]-> --dry-run (Lists the modified files without generating patches)"
+
+    echo ""
+    echo "** Follow these steps to generate patch files using this script **"
+    echo "1) Apply the patches and generate source code repo using zopen build command"
+    echo "2) Commit the files modified by applying patches"
+    echo "3) Perform development or bug fix changes on top of the commit created in step 2. Once the changes are ready, create a new commit(s)."
+    echo "4) Use this script to generate patch files (in port/patches/ directory) for the files modified in step 3."
+    echo ""
+    echo "NOTE: The source repo should not be in a detached state"
+}
+
+get_commit_ids()
+{
+    BASE_COMMIT=      # source code gets cloned with this latest commit
+    PATCHED_COMMIT=   # Run zopen build to apply all the patches from port
+    CURRENT_COMMIT=   # Commit with further dev changes
+
+    #Check here if the branch is in detached state
+    if [ $(git branch -a | grep '* ' | grep -c "detached") != 0 ] 
+    then
+        echo_error "This is in detached state, please create a branch and try again!"
+        echo_usage
+        exit 1;
+    fi
+
+    #Find the current branch name
+    curr_branch=$(git branch -a | grep '* ' | cut -d ' ' -f 2)
+
+    #Find the commit from which curr_branch diverged
+    BASE_COMMIT=$(git reflog show ${curr_branch} | grep "branch: Created" | cut -d ' ' -f 1)
+
+    #Find the first commit after curr_branch branch diverged, this is the commit 
+    #with all previous patches applied
+    PATCHED_COMMIT=$(git rev-list --reverse ${curr_branch} | grep -A1 ${BASE_COMMIT} | tail -n 1)
+
+    #Find the latest commit 
+    CURRENT_COMMIT=$(git rev-list ${curr_branch} | head -n 1)
+
+    if [[ -z ${BASE_COMMIT} || -z ${PATCHED_COMMIT} || -z ${CURRENT_COMMIT} ]]
+    then
+        echo_error "Something is wrong, BASE_COMMIT, PATCHED_COMMIT and CURRENT_COMMIT needed but are not set"
+        echo_usage
+        exit
+    fi
+}
+
+gen_patches()
+{
+    if [ ${PATCHED_COMMIT} == ${CURRENT_COMMIT} ] 
+    then
+        #Generating patch files for the first time
+        MODIFIED_FILES=$(git diff-tree --no-commit-id --name-only ${BASE_COMMIT} ${CURRENT_COMMIT} -r)
+    else
+        MODIFIED_FILES=$(git diff-tree --no-commit-id --name-only ${PATCHED_COMMIT} ${CURRENT_COMMIT} -r)
+    fi
+
+    echo -e "\nModified files:\n" 
+    echo -e "${MODIFIED_FILES}\n"
+
+    if [ ${DRY_RUN} == "true" ] ;
+    then
+        return
+    fi
+
+    for file in ${MODIFIED_FILES}
+    do
+        echo "Generating diff for ${file}"
+
+        #Save the patch files to port/patches/
+        PATCH_FILE=${PORT_DIR}/patches/${file}.patch
+        PATCH_FILE_DIR=$(dirname ${PATCH_FILE})
+
+        if [ ! -d ${PATCH_FILE_DIR} ]
+        then
+            echo "${PATCH_FILE_DIR} does not exists, creating one"
+    	    mkdir -p ${PATCH_FILE_DIR}
+        fi
+
+        if [ -f ${PATCH_FILE} ]
+        then
+            echo "WARNING: ${PATCH_FILE} already exists, contents will be overwritten"
+        fi
+
+        echo ""
+        #Generate patch file
+        git diff ${BASE_COMMIT} -- ${file} > ${PATCH_FILE}
+
+        #Add the file to the staging area
+        # cd ${PORT_DIR} ; git add ${PATCH_FILE} ; cd - 
+    done
+}
+
+## main() STARTS HERE ##
+DRY_RUN=false
+
+if [[ $# != "4" && $# != 5 ]]
+then
+    echo_usage
+    exit 1;
+fi
+
+while [ ! -z $1 ]; do
+    case "$1" in
+        -s)
+            SRC_DIR=${2}
+            shift 2
+            ;;
+        -p)
+            PORT_DIR=${2}
+            shift 2
+            ;;
+        --dry-run)
+            DRY_RUN=true
+            echo "--dry-run is set to true: modified files will be listed but patches won't be generated"
+            shift
+            break
+            ;;
+        -h | --help)
+            echo_usage
+            exit 1
+            ;;
+        :)
+            echo_error "Invalid option"
+            echo_usage
+            exit 1
+            ;;
+    esac
+done
+
+if [ ! -d ${SRC_DIR} ]
+then
+    echo_error "${SRC_DIR} does not exist"
+    echo_usage
+    exit
+fi
+
+if [ ! -d ${PORT_DIR} ]
+then
+    echo_error "${PORT_DIR} does not exist"
+    echo_usage
+    exit
+fi
+
+pushd ${SRC_DIR}
+
+get_commit_ids
+
+echo "SRC_DIR          ${SRC_DIR}"
+echo "PORT_DIR         ${PORT_DIR}"
+echo "BASE_COMMIT      ${BASE_COMMIT}"
+echo "PATCHED_COMMIT   ${PATCHED_COMMIT}"
+echo "CURRENT_COMMIT   ${CURRENT_COMMIT}"
+
+# Generate patches later
+gen_patches
+
+popd