Script to prep the sd card image

2022-09-05 09:53:39 +00:00
parent 973cb94762
commit 8e96fcc67b
3 changed files with 674 additions and 16 deletions
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,12 +1,12 @@
 {
    "name": "bbctrl",
-    "version": "1.0.10b16",
+    "version": "1.0.10b17",
    "lockfileVersion": 2,
    "requires": true,
    "packages": {
        "": {
            "name": "bbctrl",
-            "version": "1.0.10b16",
+            "version": "1.0.10b17",
            "hasInstallScript": true,
            "license": "GPL-3.0+",
            "dependencies": {
@@ -18,6 +18,7 @@
                "eslint-plugin-import": "^2.26.0",
                "eslint-plugin-n": "^15.2.5",
                "eslint-plugin-promise": "^6.0.1",
+                "glob": "^8.0.3",
                "jshint": "^2.13.4",
                "jstransformer-escape-html": "^1.1.0",
                "jstransformer-scss": "^2.0.0",
@@ -992,6 +993,25 @@
                "pako": "~1.0.5"
            }
        },
+        "node_modules/browserify/node_modules/glob": {
+            "version": "7.2.3",
+            "resolved": "https://registry.npmjs.org/glob/-/glob-7.2.3.tgz",
+            "integrity": "sha512-nFR0zLpU2YCaRxwoCJvL6UvCH2JFyFVIvwTLsIf21AuHlMskA1hhTdk+LlYJtOlYt9v6dvszD2BGRqBL+iQK9Q==",
+            "dependencies": {
+                "fs.realpath": "^1.0.0",
+                "inflight": "^1.0.4",
+                "inherits": "2",
+                "minimatch": "^3.1.1",
+                "once": "^1.3.0",
+                "path-is-absolute": "^1.0.0"
+            },
+            "engines": {
+                "node": "*"
+            },
+            "funding": {
+                "url": "https://github.com/sponsors/isaacs"
+            }
+        },
        "node_modules/buffer": {
            "version": "5.2.1",
            "resolved": "https://registry.npmjs.org/buffer/-/buffer-5.2.1.tgz",
@@ -1172,6 +1192,25 @@
                "node": ">=0.2.5"
            }
        },
+        "node_modules/cli/node_modules/glob": {
+            "version": "7.2.3",
+            "resolved": "https://registry.npmjs.org/glob/-/glob-7.2.3.tgz",
+            "integrity": "sha512-nFR0zLpU2YCaRxwoCJvL6UvCH2JFyFVIvwTLsIf21AuHlMskA1hhTdk+LlYJtOlYt9v6dvszD2BGRqBL+iQK9Q==",
+            "dependencies": {
+                "fs.realpath": "^1.0.0",
+                "inflight": "^1.0.4",
+                "inherits": "2",
+                "minimatch": "^3.1.1",
+                "once": "^1.3.0",
+                "path-is-absolute": "^1.0.0"
+            },
+            "engines": {
+                "node": "*"
+            },
+            "funding": {
+                "url": "https://github.com/sponsors/isaacs"
+            }
+        },
        "node_modules/cliui": {
            "version": "2.1.0",
            "resolved": "https://registry.npmjs.org/cliui/-/cliui-2.1.0.tgz",
@@ -2417,19 +2456,18 @@
            }
        },
        "node_modules/glob": {
-            "version": "7.2.3",
-            "resolved": "https://registry.npmjs.org/glob/-/glob-7.2.3.tgz",
-            "integrity": "sha512-nFR0zLpU2YCaRxwoCJvL6UvCH2JFyFVIvwTLsIf21AuHlMskA1hhTdk+LlYJtOlYt9v6dvszD2BGRqBL+iQK9Q==",
+            "version": "8.0.3",
+            "resolved": "https://registry.npmjs.org/glob/-/glob-8.0.3.tgz",
+            "integrity": "sha512-ull455NHSHI/Y1FqGaaYFaLGkNMMJbavMrEGFXG/PGrg6y7sutWHUHrz6gy6WEBH6akM1M414dWKCNs+IhKdiQ==",
            "dependencies": {
                "fs.realpath": "^1.0.0",
                "inflight": "^1.0.4",
                "inherits": "2",
-                "minimatch": "^3.1.1",
-                "once": "^1.3.0",
-                "path-is-absolute": "^1.0.0"
+                "minimatch": "^5.0.1",
+                "once": "^1.3.0"
            },
            "engines": {
-                "node": "*"
+                "node": ">=12"
            },
            "funding": {
                "url": "https://github.com/sponsors/isaacs"
@@ -2446,6 +2484,25 @@
                "node": ">= 6"
            }
        },
+        "node_modules/glob/node_modules/brace-expansion": {
+            "version": "2.0.1",
+            "resolved": "https://registry.npmjs.org/brace-expansion/-/brace-expansion-2.0.1.tgz",
+            "integrity": "sha512-XnAIvQ8eM+kC6aULx6wuQiwVsnzsi9d3WxzV3FpWTGA19F621kwdbsAcFKXgKUHZWsy+mY6iL1sHTxWEFCytDA==",
+            "dependencies": {
+                "balanced-match": "^1.0.0"
+            }
+        },
+        "node_modules/glob/node_modules/minimatch": {
+            "version": "5.1.0",
+            "resolved": "https://registry.npmjs.org/minimatch/-/minimatch-5.1.0.tgz",
+            "integrity": "sha512-9TPBGGak4nHfGZsPBohm9AWg6NoT7QTCehS3BIJABslyZbzxfV78QM2Y6+i741OPZIafFAaiiEMh5OyIrJPgtg==",
+            "dependencies": {
+                "brace-expansion": "^2.0.1"
+            },
+            "engines": {
+                "node": ">=10"
+            }
+        },
        "node_modules/globals": {
            "version": "13.17.0",
            "resolved": "https://registry.npmjs.org/globals/-/globals-13.17.0.tgz",
@@ -4038,6 +4095,25 @@
                "url": "https://github.com/sponsors/isaacs"
            }
        },
+        "node_modules/rimraf/node_modules/glob": {
+            "version": "7.2.3",
+            "resolved": "https://registry.npmjs.org/glob/-/glob-7.2.3.tgz",
+            "integrity": "sha512-nFR0zLpU2YCaRxwoCJvL6UvCH2JFyFVIvwTLsIf21AuHlMskA1hhTdk+LlYJtOlYt9v6dvszD2BGRqBL+iQK9Q==",
+            "dependencies": {
+                "fs.realpath": "^1.0.0",
+                "inflight": "^1.0.4",
+                "inherits": "2",
+                "minimatch": "^3.1.1",
+                "once": "^1.3.0",
+                "path-is-absolute": "^1.0.0"
+            },
+            "engines": {
+                "node": "*"
+            },
+            "funding": {
+                "url": "https://github.com/sponsors/isaacs"
+            }
+        },
        "node_modules/ripemd160": {
            "version": "2.0.2",
            "resolved": "https://registry.npmjs.org/ripemd160/-/ripemd160-2.0.2.tgz",
@@ -4390,6 +4466,25 @@
                "node": "*"
            }
        },
+        "node_modules/stylus/node_modules/glob": {
+            "version": "7.2.3",
+            "resolved": "https://registry.npmjs.org/glob/-/glob-7.2.3.tgz",
+            "integrity": "sha512-nFR0zLpU2YCaRxwoCJvL6UvCH2JFyFVIvwTLsIf21AuHlMskA1hhTdk+LlYJtOlYt9v6dvszD2BGRqBL+iQK9Q==",
+            "dependencies": {
+                "fs.realpath": "^1.0.0",
+                "inflight": "^1.0.4",
+                "inherits": "2",
+                "minimatch": "^3.1.1",
+                "once": "^1.3.0",
+                "path-is-absolute": "^1.0.0"
+            },
+            "engines": {
+                "node": "*"
+            },
+            "funding": {
+                "url": "https://github.com/sponsors/isaacs"
+            }
+        },
        "node_modules/stylus/node_modules/mkdirp": {
            "version": "1.0.4",
            "resolved": "https://registry.npmjs.org/mkdirp/-/mkdirp-1.0.4.tgz",
@@ -5454,6 +5549,21 @@
                "util": "~0.12.0",
                "vm-browserify": "^1.0.0",
                "xtend": "^4.0.0"
+            },
+            "dependencies": {
+                "glob": {
+                    "version": "7.2.3",
+                    "resolved": "https://registry.npmjs.org/glob/-/glob-7.2.3.tgz",
+                    "integrity": "sha512-nFR0zLpU2YCaRxwoCJvL6UvCH2JFyFVIvwTLsIf21AuHlMskA1hhTdk+LlYJtOlYt9v6dvszD2BGRqBL+iQK9Q==",
+                    "requires": {
+                        "fs.realpath": "^1.0.0",
+                        "inflight": "^1.0.4",
+                        "inherits": "2",
+                        "minimatch": "^3.1.1",
+                        "once": "^1.3.0",
+                        "path-is-absolute": "^1.0.0"
+                    }
+                }
            }
        },
        "browserify-aes": {
@@ -5676,6 +5786,21 @@
            "requires": {
                "exit": "0.1.2",
                "glob": "^7.1.1"
+            },
+            "dependencies": {
+                "glob": {
+                    "version": "7.2.3",
+                    "resolved": "https://registry.npmjs.org/glob/-/glob-7.2.3.tgz",
+                    "integrity": "sha512-nFR0zLpU2YCaRxwoCJvL6UvCH2JFyFVIvwTLsIf21AuHlMskA1hhTdk+LlYJtOlYt9v6dvszD2BGRqBL+iQK9Q==",
+                    "requires": {
+                        "fs.realpath": "^1.0.0",
+                        "inflight": "^1.0.4",
+                        "inherits": "2",
+                        "minimatch": "^3.1.1",
+                        "once": "^1.3.0",
+                        "path-is-absolute": "^1.0.0"
+                    }
+                }
            }
        },
        "cliui": {
@@ -6645,16 +6770,33 @@
            }
        },
        "glob": {
-            "version": "7.2.3",
-            "resolved": "https://registry.npmjs.org/glob/-/glob-7.2.3.tgz",
-            "integrity": "sha512-nFR0zLpU2YCaRxwoCJvL6UvCH2JFyFVIvwTLsIf21AuHlMskA1hhTdk+LlYJtOlYt9v6dvszD2BGRqBL+iQK9Q==",
+            "version": "8.0.3",
+            "resolved": "https://registry.npmjs.org/glob/-/glob-8.0.3.tgz",
+            "integrity": "sha512-ull455NHSHI/Y1FqGaaYFaLGkNMMJbavMrEGFXG/PGrg6y7sutWHUHrz6gy6WEBH6akM1M414dWKCNs+IhKdiQ==",
            "requires": {
                "fs.realpath": "^1.0.0",
                "inflight": "^1.0.4",
                "inherits": "2",
-                "minimatch": "^3.1.1",
-                "once": "^1.3.0",
-                "path-is-absolute": "^1.0.0"
+                "minimatch": "^5.0.1",
+                "once": "^1.3.0"
+            },
+            "dependencies": {
+                "brace-expansion": {
+                    "version": "2.0.1",
+                    "resolved": "https://registry.npmjs.org/brace-expansion/-/brace-expansion-2.0.1.tgz",
+                    "integrity": "sha512-XnAIvQ8eM+kC6aULx6wuQiwVsnzsi9d3WxzV3FpWTGA19F621kwdbsAcFKXgKUHZWsy+mY6iL1sHTxWEFCytDA==",
+                    "requires": {
+                        "balanced-match": "^1.0.0"
+                    }
+                },
+                "minimatch": {
+                    "version": "5.1.0",
+                    "resolved": "https://registry.npmjs.org/minimatch/-/minimatch-5.1.0.tgz",
+                    "integrity": "sha512-9TPBGGak4nHfGZsPBohm9AWg6NoT7QTCehS3BIJABslyZbzxfV78QM2Y6+i741OPZIafFAaiiEMh5OyIrJPgtg==",
+                    "requires": {
+                        "brace-expansion": "^2.0.1"
+                    }
+                }
            }
        },
        "glob-parent": {
@@ -7875,6 +8017,21 @@
            "integrity": "sha512-JZkJMZkAGFFPP2YqXZXPbMlMBgsxzE8ILs4lMIX/2o0L9UBw9O/Y3o6wFw/i9YLapcUJWwqbi3kdxIPdC62TIA==",
            "requires": {
                "glob": "^7.1.3"
+            },
+            "dependencies": {
+                "glob": {
+                    "version": "7.2.3",
+                    "resolved": "https://registry.npmjs.org/glob/-/glob-7.2.3.tgz",
+                    "integrity": "sha512-nFR0zLpU2YCaRxwoCJvL6UvCH2JFyFVIvwTLsIf21AuHlMskA1hhTdk+LlYJtOlYt9v6dvszD2BGRqBL+iQK9Q==",
+                    "requires": {
+                        "fs.realpath": "^1.0.0",
+                        "inflight": "^1.0.4",
+                        "inherits": "2",
+                        "minimatch": "^3.1.1",
+                        "once": "^1.3.0",
+                        "path-is-absolute": "^1.0.0"
+                    }
+                }
            }
        },
        "ripemd160": {
@@ -8129,6 +8286,19 @@
                "source-map": "^0.7.3"
            },
            "dependencies": {
+                "glob": {
+                    "version": "7.2.3",
+                    "resolved": "https://registry.npmjs.org/glob/-/glob-7.2.3.tgz",
+                    "integrity": "sha512-nFR0zLpU2YCaRxwoCJvL6UvCH2JFyFVIvwTLsIf21AuHlMskA1hhTdk+LlYJtOlYt9v6dvszD2BGRqBL+iQK9Q==",
+                    "requires": {
+                        "fs.realpath": "^1.0.0",
+                        "inflight": "^1.0.4",
+                        "inherits": "2",
+                        "minimatch": "^3.1.1",
+                        "once": "^1.3.0",
+                        "path-is-absolute": "^1.0.0"
+                    }
+                },
                "mkdirp": {
                    "version": "1.0.4",
                    "resolved": "https://registry.npmjs.org/mkdirp/-/mkdirp-1.0.4.tgz",
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
    "name": "bbctrl",
-    "version": "1.0.10b16",
+    "version": "1.0.10b17",
    "homepage": "https://onefinitycnc.com/",
    "repository": "https://github.com/OneFinityCNC/onefinity",
    "license": "GPL-3.0+",
@@ -16,6 +16,7 @@
        "eslint-plugin-import": "^2.26.0",
        "eslint-plugin-n": "^15.2.5",
        "eslint-plugin-promise": "^6.0.1",
+        "glob": "^8.0.3",
        "jshint": "^2.13.4",
        "jstransformer-escape-html": "^1.1.0",
        "jstransformer-scss": "^2.0.0",
--- a/scripts/prep-sd-image.js
+++ b/scripts/prep-sd-image.js
@@ -0,0 +1,487 @@
+#!/usr/bin/env node
+
+const { basename, extname, resolve } = require("path");
+const { parseArgs } = require("node:util");
+const { statSync, rmdirSync, copyFileSync } = require("fs");
+const { execSync } = require("child_process");
+const { exit } = require("process");
+const { glob } = require("glob");
+const packageJSON = require("../package.json")
+
+const ARGS_CONFIG = {
+    options: {
+        input: {
+            type: "string",
+            short: "i"
+        },
+        help: {
+            type: "boolean",
+            short: "h"
+        }
+    }
+};
+
+const REQUIRED_TOOLS = [
+    "rsync",
+    "parted",
+    "losetup",
+    "tune2fs",
+    "md5sum",
+    "e2fsck",
+    "resize2fs",
+    "xz",
+    "zerofree"
+];
+
+const USER_FILES = [
+    ".bash_history",
+    ".nano",
+    ".cache",
+    ".lesshst",
+    ".wget-hsts",
+    ".viminfo",
+    ".local",
+    ".pki",
+    ".ratpoison_history",
+    ".Xauthority",
+    {
+        pattern: ".config/**",
+        ignore: [
+            "**/home/pi/.config",
+            "**/home/pi/.config/chromium",
+            "**/home/pi/.config/chromium/Default",
+            "**/home/pi/.config/chromium/Default/Extensions",
+            "**/home/pi/.config/chromium/Default/Extensions/*"
+        ]
+    },
+    "Downloads",
+    "splash.png"
+];
+
+let signalHandlers = [];
+
+function registerSignalHandler(cb) {
+    signalHandlers.push(cb);
+
+    return () => (signalHandlers = signalHandlers.filter(h => h === cb));
+}
+
+function handle(signal) {
+    console.log(`Received ${signal}`);
+
+    for (const handler of signalHandlers) {
+        handler(signal);
+    }
+}
+
+process.on("SIGTERM", handle);
+process.on("SIGINT", handle);
+process.on("SIGHUP", handle);
+
+main();
+
+function main() {
+    try {
+        const { values: { input, help } } = parseArgs(ARGS_CONFIG);
+
+        if (!input || help) {
+            displayUsageAndExit();
+        }
+
+        assertOS();
+        assertEffectiveRoot();
+        assertFileExists(input);
+        assertInstalled(REQUIRED_TOOLS);
+
+        const target = createTargetFile(input);
+
+        attachToLoopback(target, (loopback, meta) => {
+            checkAndRepair(loopback);
+            prepareFilesystem(loopback);
+            shrinkFilesystem(loopback);
+            shrinkPartition(target, loopback, meta);
+            zerofree(loopback);
+            truncateImage(target, meta);
+            compress(target, meta);
+        });
+    } catch (error) {
+        switch (error.code) {
+            case "ERR_PARSE_ARGS_UNEXPECTED_POSITIONAL":
+                displayUsageAndExit();
+        }
+
+        console.error(error);
+    }
+}
+
+function assertOS() {
+    if (process.platform !== "linux") {
+        logErrorAndExit("This script requires linux.");
+    }
+}
+
+function assertEffectiveRoot() {
+    if (process.geteuid() !== 0) {
+        logErrorAndExit("Please run this script as root");
+    }
+}
+
+function assertFileExists(file) {
+    const stats = statSync(file);
+    if (!stats.isFile) {
+        logErrorAndExit(`${file} does not exist`);
+    }
+}
+
+function assertInstalled(tools) {
+    const missingTools = [];
+
+    for (const tool of tools) {
+        runCommand(`command -v ${tool}`, {
+            onError: () => missingTools.push(tool)
+        });
+    }
+
+    if (missingTools.length) {
+        logErrorAndExit(`
+            This script requires some tools that are not installed.
+
+            Install them via:
+                apt-get install -y ${missingTools.join(" ")}
+        `);
+    }
+}
+
+function createTargetFile(file) {
+    const target = `onefinity-raspi-${packageJSON.version}.img`;
+
+    return doStep(`Copying ${file} to ${target}...`, () => {
+        runCommand(`rsync --times --progress ${file} ${target}`, {
+            stdio: "inherit",
+            onError: error => {
+                logErrorAndExit(`Failed to copy ${file} to ${target}`, error);
+            }
+        });
+
+        return target;
+    });
+}
+
+function attachToLoopback(file, cb) {
+    const meta = gatherMetadata(file);
+
+    return doStep("Attaching the image to a loopback device...", () => {
+        const loopback = runCommand(`losetup -f --show -o "${meta.rootPartition.start}" "${file}"`);
+
+        const finallyHandler = () => runCommand(`losetup -d ${loopback}`);
+        const unregister = registerSignalHandler(finallyHandler);
+
+        try {
+            cb(loopback, meta);
+        } finally {
+            finallyHandler();
+            unregister();
+        }
+    });
+}
+
+function gatherMetadata(file) {
+    return doStep("Gathering info about the image...", () => {
+        const { size: initialImageSize } = statSync(file);
+
+        const partedOutput = runCommand(`parted -s "${file}" unit B print`, {
+            onError: error => {
+                logErrorAndExit(`
+                Error fetching disk image info.
+
+                'parted' failed with exitcode ${error.status}
+                
+                Run 'parted ${file} unit B print' manually to investigate
+            `, error);
+            }
+        });
+
+        const [ number, start, end, size, type, filesystem, flags ] = partedOutput
+            .split("\n")
+            .at(-1)
+            .trim()
+            .split(/\s+/)
+            .map(col => parseInt(col) || col);
+
+        return {
+            initialImageSize,
+            rootPartition: {
+                number,
+                start,
+                end,
+                size,
+                type,
+                filesystem,
+                flags
+            }
+        };
+    });
+
+/*
+currentsize="$(echo "$tune2fs_output" | grep '^Block count:' | tr -d ' ' | cut -d ':' -f 2)"
+blocksize="$(echo "$tune2fs_output" | grep '^Block size:' | tr -d ' ' | cut -d ':' -f 2)"
+partnewsize=$(($currentsize * $blocksize))
+newpartend=$(($partstart + $partnewsize))
+
+*/
+}
+
+function checkAndRepair(loopback) {
+    return doStep("Checking the filesystem...", () => {
+        runCommand(`e2fsck -yf ${loopback}`, {
+            stdio: "inherit"
+        });
+    });
+}
+
+function prepareFilesystem(loopback) {
+    const mountpoint = runCommand("mktemp -d");
+
+    const finallyHandler = () => {
+        info("Unmounting the filesystem");
+        runCommand(`umount "${mountpoint}"`);
+        rmdirSync(mountpoint);
+    };
+    const unregister = registerSignalHandler(finallyHandler);
+
+    try {
+        doStep("Removing unnecessary files from the filesystem...", () => {
+            runCommand(`mount ${loopback} ${mountpoint}`);
+
+            scrub(mountpoint, [
+                "/etc/ssh/*_host_*",
+                "/var/swap",
+                "/tmp/*",
+                "/usr/**/__pycache__",
+                "/usr/**/*.py[co]",
+                "/usr/share/doc/*",
+                "/usr/share/plymouth/themes/buildbotics",
+                "/var/@(cache|backups|log|tmp)/*",
+                "/var/lib/apt/lists/*",
+                "/var/lib/bbctrl/@(firmware|plans|upload)/*",
+                "/var/lib/bbctrl/@(config|gamepads).json",
+                "/var/lib/dhcpcd5/*"
+            ]);
+
+            scrubUserFiles(mountpoint, "/root");
+            scrubUserFiles(mountpoint, "/home/bbmc");
+            scrubUserFiles(mountpoint, "/home/pi");
+        });
+
+        doStep("Injecting files...", () => {
+            copyFileSync(resolve(`${__dirname}/../installer/Team Onefinity.ngc`), resolve(`${mountpoint}/var/lib/bbctrl/upload/Team Onefinity.ngc`));
+        });
+    } finally {
+        finallyHandler();
+        unregister();
+    }
+}
+
+function shrinkFilesystem(loopback) {
+    return doStep(`Shrinking the root filesystem`, () => {
+        runCommand(`resize2fs -p "${loopback}" -M`, {
+            stdio: "inherit",
+            onError: error => {
+                logErrorAndExit("Error while resizing", error);
+            }
+        });
+    });
+}
+
+function shrinkPartition(target, loopback, meta) {
+    return doStep(`Shrinking the root partition`, () => {
+        const tune2fsOutput = runCommand(`tune2fs -l "${loopback}"`, {
+            onError: error => logErrorAndExit("tune2fs failed. Unable to shrink this type of image", error)
+        });
+
+        const [ , currentSize ] = tune2fsOutput.match(/^Block count:\s+(\d+)/m);
+        const [ , blockSize ] = tune2fsOutput.match(/^Block size:\s+(\d+)/m);
+        const newSize = parseInt(currentSize) * parseInt(blockSize);
+        const newEnd = meta.rootPartition.start + newSize;
+
+        runCommand(`parted -s -a minimal "${target}" rm "${meta.rootPartition.number}"`, {
+            onError: error => logErrorAndExit("parted failed while deleting root partition", error)
+        });
+
+        runCommand(`parted -s "${target}" unit B mkpart "${meta.rootPartition.type}" "${meta.rootPartition.start}" "${newEnd}"`, {
+            onError: error => logErrorAndExit("parted failed while recreating the root partition", error)
+        });
+    });
+}
+
+function zerofree(loopback) {
+    return doStep(`Setting empty blocks to zeros`, () => {
+        info("(This will take a bit - it can look like it's hung, have patience)");
+        runCommand(`zerofree -v "${loopback}"`, {
+            stdio: "inherit"
+        });
+    });
+}
+
+function truncateImage(target, meta) {
+    return doStep(`Shrinking the image`, () => {
+        const partedOutput = runCommand(`parted -s "${target}" unit B print free`, {
+            onError: error => logErrorAndExit("parted failed while shrinking the image", error)
+        });
+
+        const [ startOfFreeSpace ] = partedOutput
+            .split("\n")
+            .at(-1)
+            .trim()
+            .split(/\s+/)
+            .map(col => parseInt(col) || col);
+
+        runCommand(`truncate -s "${startOfFreeSpace}" "${target}"`);
+
+        const { size: newSize } = statSync(target);
+        info(`Shrunk ${target} from ${meta.initialImageSize} to ${newSize}`);
+    });
+}
+
+function compress(target, meta) {
+    return doStep(`Compressing the image`, () => {
+        runCommand(`xz -k9veT0 ${target}`, {
+            stdio: "inherit"
+        });
+
+        const compressed = `${target}.xz`;
+
+        const { size: newSize } = statSync(compressed);
+        info(`Shrunk ${target} from ${meta.initialImageSize} to ${newSize} (${compressed})`);
+    });
+}
+
+function scrub(mountpoint, patterns) {
+    for (const _pattern of patterns) {
+        const { pattern, ignore } = (typeof _pattern === "string")
+            ? { pattern: _pattern }
+            : _pattern;
+
+        const options = {
+            dot: true,
+            cwd: mountpoint,
+            root: mountpoint,
+            ignore
+        };
+
+        const matches = glob.sync(pattern, options);
+
+        for (const match of matches) {
+            runCommand(`rm -rvf "${match}"`, {
+                stdio: "inherit"
+            });
+        }
+    }
+}
+
+function scrubUserFiles(mountpoint, homedir) {
+    scrub(mountpoint, USER_FILES.map(item => {
+        if (typeof item === "string") {
+            return `${homedir}/${item}`;
+        }
+
+        return {
+            ...item,
+            pattern: `${homedir}/${item.pattern}`,
+        };
+    }));
+}
+
+function doStep(msg, cb) {
+    info(msg);
+
+    return cb();
+}
+
+function info(msg) {
+    console.log(`\n${msg}`);
+}
+
+function runCommand(command, _options) {
+    const options = {
+        encoding: "utf8",
+        ..._options,
+        shell: true
+    };
+
+    const { onError } = options;
+    delete options["onError"];
+
+    try {
+        const result = execSync(command, options);
+
+        return (typeof result === "string")
+            ? result.trim()
+            : result;
+    } catch (error) {
+        if (onError) {
+            onError(error);
+        } else {
+            throw error;
+        }
+    }
+}
+
+function logErrorAndExit(msg, error) {
+    const lines = msg.split("\n");
+
+    // Get rid of leading blank lines
+    while (lines.length) {
+        if (lines[0].trim().length == 0) {
+            lines.shift();
+        } else {
+            break;
+        }
+    }
+
+    // Get rid of trailing blank lines
+    while (lines.length) {
+        if (lines.at(-1).trim().length == 0) {
+            lines.pop();
+        } else {
+            break;
+        }
+    }
+
+    const [ whitespace ] = lines[0].match(/^\s*/);
+
+    console.error(lines
+        .map(line => line.replace(whitespace, "").trimEnd())
+        .join("\n")
+    );
+
+    if (error) {
+        console.error("Error:", {
+            name: error.name,
+            code: error.code,
+            message: error.message
+        });
+    }
+
+    exit(1);
+}
+
+function displayUsageAndExit() {
+    logErrorAndExit(`
+        Usage: ${basename(process.argv[1])} --input <sd-card-image-file>
+
+        This tool will:
+            - Check and repair the file system, if needed
+            - Remove unnecessary files from the root partition
+            - Shrink the root partition as much as possible
+            - Truncate the image file to be as small as possible
+            - Overwrite all filesystem blank space with zeros (better compression)
+            - Compress the output image
+
+        Two output files will be produced:
+            <sd-card-image-file>.shrunk.img (uncompressed)
+            <sd-card-image-file>.shrunk.img.xz (compressed)
+    `);
+
+    exit(1);
+}