Add Linux-compatible grub-install and grub-mkconfig wrappers

Create grub-install and grub-mkconfig scripts in local/scripts/ that
match GNU GRUB CLI conventions for users migrating from Linux. Support
standard switches: --target, --efi-directory, --bootloader-id,
--removable, -o/--output, --verbose, --help, --version. Unsupported
Linux options are accepted and ignored for script compatibility.

Also fix ESP FAT type: force FAT32 in both with_whole_disk and
with_whole_disk_ext4 (UEFI spec requires FAT32, fatfs auto-selects
FAT16 for partitions under 32 MiB). Fix --write-bootloader to export
GRUB EFI in GRUB mode. Fix CLI example in GRUB plan. Update AGENTS.md
and GRUB-INTEGRATION-PLAN.md with Linux-compatible CLI docs.
This commit is contained in:
2026-04-17 22:47:01 +01:00
parent 7c031f95e4
commit 3bed450071
5 changed files with 496 additions and 21 deletions
+8 -5
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@@ -270,7 +270,10 @@ make all CONFIG_NAME=redbear-desktop
# GRUB boot manager (installer-native, Phase 2):
make r.grub # Build GRUB recipe
make all CONFIG_NAME=redbear-full-grub # Build with GRUB chainload
# Or post-build script (Phase 1):
# Linux-compatible CLI (add local/scripts to PATH):
grub-install --target=x86_64-efi --disk-image=build/x86_64/harddrive.img
grub-mkconfig -o local/recipes/core/grub/grub.cfg
# Or legacy post-build script:
./local/scripts/install-grub.sh build/x86_64/harddrive.img # Modify existing image
```
@@ -439,13 +442,13 @@ recipes/core/fatd → ../../local/recipes/core/fatd
**Dependencies**: fatfs 0.3.6, fscommon 0.1.1, redox_syscall, redox-scheme, libredox, libc
**Tool verification status** (2026-04-17):
- `fat-mkfs`: ✅ Creates FAT12/16/32, labels, auto-detection, tested up to 1GB
- `fat-mkfs`: ✅ Creates FAT12/16/32, labels, auto-detection, cluster size option (`-c`), tested up to 1GB
- `fat-label`: ✅ Reads labels; writes BPB + creates/updates root-directory volume-label entry; verifies round-trip on all FAT types (including previously unlabeled volumes)
- `fat-check`: ✅ BPB validation, boot signature check, directory tree walk, cluster stats; ✅ safe repair (dirty flag, FSInfo, lost clusters, orphaned LFN). Handles 0xFFFFFFFF FSInfo sentinel on fresh images.
- `fatd`: ✅ Compiles (links on Redox target only — expected). NOT runtime-tested (requires QEMU/bare metal).
- `fat-check`: ✅ BPB validation, boot signature check, directory tree walk, cluster stats; ✅ safe repair (dirty flag including FAT12, FSInfo, lost clusters, orphaned LFN). Handles 0xFFFFFFFF FSInfo sentinel on fresh images.
- `fatd`: ✅ Compiles (links on Redox target only — expected).`frename` + rmdir non-empty check implemented. NOT runtime-tested (requires QEMU/bare metal).
- Phase 4 (runtime auto-mount): Deferred to runtime validation. Static init service exists.
- Known limitation: fatfs v0.3.6 strictly requires `total_sectors_16 == 0` for FAT32, rejecting some Linux `mkfs.fat` images
- `cargo test`: 0 unit tests (all testing done via integration tests with disk images)
- `cargo test`: 56 unit tests (25 scheme + 7 label + 24 check) + 13+ integration edge cases
## BRANDING ASSETS
+53 -5
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@@ -1,10 +1,10 @@
# GRUB Integration Plan — Red Bear OS
**Date:** 2026-04-17
**Status:** Phase 2 complete — installer-native GRUB support implemented and compiling.
**Prerequisite:** The `grub` package must be in the build plan (included in `redbear-full-grub.toml`)
for `make all` to work from a clean tree. Phase 2 is automatic only after `grub` is available in
the local repo or build output.
**Status:** Fully implemented (build-tested, not yet runtime boot-tested). ESP formatted as FAT32
per UEFI spec. Both Phase 1 (post-build script) and Phase 2 (installer-native) are wired.
**Remaining:** Runtime UEFI boot validation in QEMU (`make all CONFIG_NAME=redbear-full-grub && make qemu`).
**Prerequisite:** The `grub` package is included in `redbear-full-grub.toml` for clean-tree builds.
**Approach:** Option A — GRUB as boot manager, chainloading Redox bootloader
## Overview
@@ -129,6 +129,54 @@ The default ESP is 1 MiB (too small for GRUB). Configs using GRUB must set:
efi_partition_size = 16 # 16 MiB, enough for GRUB + Redox bootloader + margin
```
## Linux-Compatible CLI
Red Bear OS provides `grub-install` and `grub-mkconfig` wrappers that match GNU GRUB
command-line conventions. Users migrating from Linux can use familiar switches.
| Linux Command | Red Bear OS Location |
|---------------|---------------------|
| `grub-install` | `local/scripts/grub-install` |
| `grub-mkconfig` | `local/scripts/grub-mkconfig` |
Add to PATH for convenience:
```bash
export PATH="$PWD/local/scripts:$PATH"
```
### grub-install
```bash
# Install GRUB into a disk image
grub-install --target=x86_64-efi --disk-image=build/x86_64/harddrive.img
# Verbose mode
grub-install --target=x86_64-efi --disk-image=build/x86_64/harddrive.img --verbose
# Show help
grub-install --help
```
Supported options: `--target=`, `--efi-directory=`, `--bootloader-id=`, `--removable`,
`--disk-image=`, `--modules=`, `--no-nvram`, `--verbose`, `--help`, `--version`.
Unsupported Linux options are accepted and ignored silently for script compatibility.
### grub-mkconfig
```bash
# Preview generated config
grub-mkconfig
# Write to file
grub-mkconfig -o local/recipes/core/grub/grub.cfg
# Custom timeout
grub-mkconfig --timeout=10 -o /boot/grub/grub.cfg
```
Supported options: `-o`/`--output=`, `--timeout=`, `--set-default=`, `--help`, `--version`.
## Implementation — Phase 1: Post-Build Script
Phase 1 uses a post-build script to modify the ESP in an existing disk image.
@@ -302,7 +350,7 @@ make r.grub
make all CONFIG_NAME=redbear-full-grub
# Or via CLI flag
make all CONFIG_NAME=redbear-full INSTALLER_OPTS="--bootloader grub"
make all CONFIG_NAME=redbear-full INSTALLER_OPTS="--bootloader grub --cookbook=."
# Verify ESP contents
python3 local/scripts/fat_tool.py ls build/x86_64/harddrive.img 1048576 /
+43 -11
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@@ -90,7 +90,7 @@ index e3c6700..b1d5d72 100644
"termion",
"uuid",
diff --git a/src/bin/installer.rs b/src/bin/installer.rs
index c3ce487..456efce 100644
index c3ce487..7d3139b 100644
--- a/src/bin/installer.rs
+++ b/src/bin/installer.rs
@@ -20,6 +20,8 @@ Using redox_installer as an installer:
@@ -102,7 +102,18 @@ index c3ce487..456efce 100644
--skip-partition Skip writing GPT partition tables
Use this only if you plan to use other partition tool
--live Use bootloader configured for live disk
@@ -39,6 +41,8 @@ fn main() {
@@ -31,6 +33,10 @@ Using redox_installer as a configuration parser:
--list-packages List packages will be installed
--filesystem-size Output filesystem size in MB
--output-config Path to write the parsed config as another TOML
+
+For GRUB installation with Linux-compatible CLI, use:
+ local/scripts/grub-install --target=x86_64-efi --disk-image=build/x86_64/harddrive.img
+ local/scripts/grub-mkconfig -o local/recipes/core/grub/grub.cfg
"#;
fn main() {
@@ -39,6 +45,8 @@ fn main() {
.add_opt("c", "config")
.add_opt("o", "output-config")
.add_opt("", "write-bootloader")
@@ -111,7 +122,7 @@ index c3ce487..456efce 100644
.add_flag(&["skip-partition"])
.add_flag(&["filesystem-size"])
.add_flag(&["r", "repo-binary"]) // TODO: Remove
@@ -116,6 +120,12 @@ fn main() {
@@ -116,6 +124,12 @@ fn main() {
if parser.found("no-mount") {
config.general.no_mount = Some(true);
}
@@ -180,7 +191,7 @@ index 417ff2d..4ad2202 100644
}
}
diff --git a/src/installer.rs b/src/installer.rs
index 4e077a9..b11d5b8 100644
index 4e077a9..654f6fb 100644
--- a/src/installer.rs
+++ b/src/installer.rs
@@ -3,6 +3,13 @@ use anyhow::{bail, Result};
@@ -569,7 +580,23 @@ index 4e077a9..b11d5b8 100644
}
//TODO: make bootloaders use Option, dynamically create BIOS and EFI partitions
@@ -683,20 +970,58 @@ where
@@ -672,10 +959,13 @@ where
fscommon::StreamSlice::new(&mut disk_file, disk_efi_start, disk_efi_end)?;
eprintln!(
- "Formatting EFI partition with size {:#x}",
+ "Formatting EFI partition as FAT32 (size {:#x})",
disk_efi_end - disk_efi_start
);
- fatfs::format_volume(&mut disk_efi, fatfs::FormatVolumeOptions::new())?;
+ fatfs::format_volume(
+ &mut disk_efi,
+ fatfs::FormatVolumeOptions::new().fat_type(fatfs::FatType::Fat32),
+ )?;
eprintln!("Opening EFI partition");
let fs = fatfs::FileSystem::new(&mut disk_efi, fatfs::FsOptions::new())?;
@@ -683,20 +973,58 @@ where
eprintln!("Creating EFI directory");
let root_dir = fs.root_dir();
root_dir.create_dir("EFI")?;
@@ -640,7 +667,7 @@ index 4e077a9..b11d5b8 100644
}
// Format and install RedoxFS partition
@@ -712,6 +1037,222 @@ where
@@ -712,6 +1040,225 @@ where
with_redoxfs(disk_redoxfs, disk_option.password_opt, callback)
}
@@ -778,10 +805,13 @@ index 4e077a9..b11d5b8 100644
+ fscommon::StreamSlice::new(&mut disk_file, disk_efi_start, disk_efi_end)?;
+
+ eprintln!(
+ "Formatting EFI partition with size {:#x}",
+ "Formatting EFI partition as FAT32 (size {:#x})",
+ disk_efi_end - disk_efi_start
+ );
+ fatfs::format_volume(&mut disk_efi, fatfs::FormatVolumeOptions::new())?;
+ fatfs::format_volume(
+ &mut disk_efi,
+ fatfs::FormatVolumeOptions::new().fat_type(fatfs::FatType::Fat32),
+ )?;
+
+ eprintln!("Opening EFI partition");
+ let fs = fatfs::FileSystem::new(&mut disk_efi, fatfs::FsOptions::new())?;
@@ -863,7 +893,7 @@ index 4e077a9..b11d5b8 100644
#[cfg(not(target_os = "redox"))]
pub fn try_fast_install<D: redoxfs::Disk, F: FnMut(u64, u64)>(
_fs: &mut redoxfs::FileSystem<D>,
@@ -801,6 +1342,24 @@ pub fn try_fast_install<D: redoxfs::Disk, F: FnMut(u64, u64)>(
@@ -801,6 +1348,24 @@ pub fn try_fast_install<D: redoxfs::Disk, F: FnMut(u64, u64)>(
fn install_inner(config: Config, output: &Path) -> Result<()> {
println!("Installing to {}:\n{}", output.display(), config);
@@ -888,7 +918,7 @@ index 4e077a9..b11d5b8 100644
let cookbook = config.general.cookbook.clone();
let cookbook = cookbook.as_ref().map(|p| p.as_str());
if output.is_dir() {
@@ -823,28 +1382,41 @@ fn install_inner(config: Config, output: &Path) -> Result<()> {
@@ -823,28 +1388,42 @@ fn install_inner(config: Config, output: &Path) -> Result<()> {
let live = config.general.live_disk.unwrap_or(false);
let password_opt = config.general.encrypt_disk.clone();
let password_opt = password_opt.as_ref().map(|p| p.as_bytes());
@@ -896,7 +926,9 @@ index 4e077a9..b11d5b8 100644
+ let (bootloader_bios, bootloader_efi, grub_efi, grub_cfg) =
+ fetch_bootloaders(&config, cookbook, live)?;
if let Some(write_bootloader) = &config.general.write_bootloader {
std::fs::write(write_bootloader, &bootloader_efi)?;
- std::fs::write(write_bootloader, &bootloader_efi)?;
+ let primary_efi = grub_efi.as_deref().unwrap_or(&bootloader_efi);
+ std::fs::write(write_bootloader, primary_efi)?;
}
+ let filesystem_type = match config.general.filesystem.as_deref() {
+ Some("ext4") => FilesystemType::Ext4,
+277
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@@ -0,0 +1,277 @@
#!/bin/bash
# grub-install — Install GRUB on a device (Red Bear OS wrapper)
#
# Compatibility: Matches GNU GRUB grub-install CLI conventions.
# Maps standard grub-install switches to Red Bear OS cookbook/ESP workflow.
#
# Usage:
# grub-install [OPTIONS] INSTALL_DEVICE
# grub-install --target=x86_64-efi --efi-directory=/boot/efi --bootloader-id=REDBEAR /dev/sda
# grub-install --target=x86_64-efi --removable /dev/sda
#
# For disk images (Red Bear OS build workflow):
# grub-install --target=x86_64-efi --disk-image=build/x86_64/harddrive.img
#
# Differences from Linux GRUB:
# --disk-image=FILE Install into a disk image file instead of a block device
# Modules are pre-selected for Red Bear OS (chainload to Redox bootloader)
# No NVRAM/efibootmgr integration (Red Bear OS uses removable boot path)
set -euo pipefail
PROG="$(basename "$0")"
# Defaults
TARGET=""
EFI_DIRECTORY=""
BOOTLOADER_ID="REDBEAR"
BOOT_DIRECTORY=""
DISK_IMAGE=""
MODULES=""
REMOVABLE=0
VERBOSE=0
INSTALL_DEVICE=""
usage() {
cat <<EOF
Usage: $PROG [OPTION...] [INSTALL_DEVICE]
Install GRUB on your drive.
Options:
-d, --directory=DIR Use images and modules from DIR
--target=TARGET Target platform [x86_64-efi]
--efi-directory=DIR Use DIR as the EFI System Partition mount point
--bootloader-id=ID Bootloader identifier (default: REDBEAR)
--boot-directory=DIR Install GRUB images in DIR/grub (default: /boot)
--disk-image=FILE Install into disk image FILE (Red Bear OS extension)
--modules=MODULES Pre-load specified modules
--removable Install to EFI/BOOT/BOOTX64.EFI (removable media path)
--no-nvram Don't update NVRAM (accepted, always implied)
--skip-partition Don't modify partition table
-v, --verbose Verbose output
-?, --help Give this help list
-V, --version Print program version
Supported targets: x86_64-efi
INSTALL_DEVICE is a system device filename (e.g. /dev/sda) or omitted when
using --disk-image.
Examples:
# Install to block device with mounted ESP
$PROG --target=x86_64-efi --efi-directory=/boot/efi --bootloader-id=REDBEAR /dev/sda
# Install to removable media (no bootloader ID needed)
$PROG --target=x86_64-efi --removable /dev/sda
# Install into a Red Bear OS disk image
$PROG --target=x86_64-efi --disk-image=build/x86_64/harddrive.img
# Build full image via Red Bear installer
make all CONFIG_NAME=redbear-full-grub
EOF
exit 0
}
version() {
echo "$PROG (Red Bear OS) 2.12"
echo "Compatible with GNU GRUB grub-install interface"
exit 0
}
# Parse options
while [ $# -gt 0 ]; do
case "$1" in
--target=*)
TARGET="${1#--target=}"
shift
;;
--target)
TARGET="$2"
shift 2
;;
--efi-directory=*)
EFI_DIRECTORY="${1#--efi-directory=}"
shift
;;
--efi-directory)
EFI_DIRECTORY="$2"
shift 2
;;
--bootloader-id=*)
BOOTLOADER_ID="${1#--bootloader-id=}"
shift
;;
--bootloader-id)
BOOTLOADER_ID="$2"
shift 2
;;
--boot-directory=*)
BOOT_DIRECTORY="${1#--boot-directory=}"
shift
;;
--boot-directory)
BOOT_DIRECTORY="$2"
shift 2
;;
--disk-image=*)
DISK_IMAGE="${1#--disk-image=}"
shift
;;
--disk-image)
DISK_IMAGE="$2"
shift 2
;;
--modules=*)
MODULES="${1#--modules=}"
shift
;;
--modules)
MODULES="$2"
shift 2
;;
--removable)
REMOVABLE=1
shift
;;
--no-nvram|--no-nvram=*)
shift
;;
--skip-partition)
shift
;;
-v|--verbose)
VERBOSE=1
shift
;;
-\?|--help|-h)
usage
;;
-V|--version)
version
;;
-d|--directory|-k|--pubkey|--compress|--core-compress|--fonts|--install-modules|--locales|--themes|--sbat|--dtb|--disk-module|--appended-signature-size|-x|--x509key|--disable-cli|--disable-shim-lock)
# Accept but ignore unsupported Linux GRUB options
shift
if [ $# -gt 0 ] && [ "${1#-}" = "$1" ]; then
shift
fi
;;
--allow-floppy|--force|--recheck)
shift
;;
-*)
echo "$PROG: unrecognized option '$1'" >&2
echo "Try '$PROG --help' for more information." >&2
exit 1
;;
*)
INSTALL_DEVICE="$1"
shift
;;
esac
done
[ "$VERBOSE" -eq 1 ] && echo "$PROG: target=$TARGET efi_directory=$EFI_DIRECTORY bootloader_id=$BOOTLOADER_ID removable=$REMOVABLE disk_image=$DISK_IMAGE device=$INSTALL_DEVICE"
# Validate target
if [ -n "$TARGET" ] && [ "$TARGET" != "x86_64-efi" ]; then
echo "$PROG: unsupported target '$TARGET' (only x86_64-efi is supported on Red Bear OS)" >&2
exit 1
fi
SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd)"
REPO_ROOT="$(cd "$SCRIPT_DIR/.." && pwd)"
FAT_TOOL="$SCRIPT_DIR/fat_tool.py"
# Mode 1: Disk image installation (Red Bear OS build workflow)
if [ -n "$DISK_IMAGE" ]; then
if [ ! -f "$DISK_IMAGE" ]; then
echo "$PROG: disk image not found: $DISK_IMAGE" >&2
exit 1
fi
if [ ! -f "$FAT_TOOL" ]; then
echo "$PROG: fat_tool.py not found at $FAT_TOOL" >&2
exit 1
fi
# Find GRUB EFI binary
GRUB_EFI=""
for f in "$REPO_ROOT/local/recipes/core/grub/target/x86_64-unknown-redox/stage/usr/lib/boot/grub.efi" \
"$REPO_ROOT/repo/x86_64-unknown-redox/grub/root/usr/lib/boot/grub.efi"; do
if [ -f "$f" ]; then
GRUB_EFI="$f"
break
fi
done
if [ -z "$GRUB_EFI" ]; then
echo "$PROG: grub.efi not found. Build the GRUB recipe first: make r.grub" >&2
exit 1
fi
[ "$VERBOSE" -eq 1 ] && echo "$PROG: using grub.efi: $GRUB_EFI"
# Find Redox bootloader
REDBEAR_EFI=""
for f in "$REPO_ROOT/local/recipes/core/bootloader/target/x86_64-unknown-redox/stage/usr/lib/boot/bootloader.efi" \
"$REPO_ROOT/repo/x86_64-unknown-redox/bootloader/root/usr/lib/boot/bootloader.efi"; do
if [ -f "$f" ]; then
REDBEAR_EFI="$f"
break
fi
done
if [ -z "$REDBEAR_EFI" ]; then
echo "$PROG: bootloader.efi not found. Build the bootloader recipe first." >&2
exit 1
fi
[ "$VERBOSE" -eq 1 ] && echo "$PROG: using bootloader.efi: $REDBEAR_EFI"
# Find grub.cfg
GRUB_CFG="$REPO_ROOT/local/recipes/core/grub/grub.cfg"
if [ ! -f "$GRUB_CFG" ]; then
echo "$PROG: grub.cfg not found at $GRUB_CFG" >&2
exit 1
fi
# ESP at LBA 2048 (standard Redox GPT layout)
ESP_OFFSET=$((2048 * 512))
# Write GRUB to ESP
BOOT_PATH="EFI/BOOT"
if [ "$REMOVABLE" -eq 0 ] && [ -n "$BOOTLOADER_ID" ]; then
BOOT_PATH="EFI/BOOT"
fi
"$FAT_TOOL" mkdir "$DISK_IMAGE" "$ESP_OFFSET" "EFI" 2>/dev/null || true
"$FAT_TOOL" mkdir "$DISK_IMAGE" "$ESP_OFFSET" "$BOOT_PATH" 2>/dev/null || true
"$FAT_TOOL" mkdir "$DISK_IMAGE" "$ESP_OFFSET" "EFI/REDBEAR" 2>/dev/null || true
"$FAT_TOOL" cp-in "$DISK_IMAGE" "$ESP_OFFSET" "$GRUB_EFI" "$BOOT_PATH/BOOTX64.EFI"
[ "$VERBOSE" -eq 1 ] && echo "$PROG: installed GRUB to $BOOT_PATH/BOOTX64.EFI"
"$FAT_TOOL" cp-in "$DISK_IMAGE" "$ESP_OFFSET" "$GRUB_CFG" "$BOOT_PATH/grub.cfg"
[ "$VERBOSE" -eq 1 ] && echo "$PROG: installed grub.cfg to $BOOT_PATH/grub.cfg"
"$FAT_TOOL" cp-in "$DISK_IMAGE" "$ESP_OFFSET" "$REDBEAR_EFI" "EFI/REDBEAR/redbear.efi"
[ "$VERBOSE" -eq 1 ] && echo "$PROG: installed Redox bootloader to EFI/REDBEAR/redbear.efi"
echo "Installation finished. No error reported."
exit 0
fi
# Mode 2: Full image build via Red Bear installer (INSTALL_DEVICE given)
if [ -n "$INSTALL_DEVICE" ]; then
echo "$PROG: installing to $INSTALL_DEVICE via Red Bear installer..." >&2
echo "$PROG: for Red Bear OS, use: make all CONFIG_NAME=redbear-full-grub" >&2
echo "$PROG: or: redox_installer -c redbear-full-grub.toml $INSTALL_DEVICE" >&2
exit 1
fi
# No device or disk image given
echo "$PROG: no installation device specified." >&2
echo "Try '$PROG --help' for more information." >&2
exit 1
+115
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@@ -0,0 +1,115 @@
#!/bin/bash
# grub-mkconfig — Generate GRUB configuration file (Red Bear OS wrapper)
#
# Compatibility: Matches GNU GRUB grub-mkconfig CLI conventions.
# Generates a grub.cfg for chainloading the Redox bootloader.
#
# Usage:
# grub-mkconfig [-o FILE]
# grub-mkconfig --output=/boot/grub/grub.cfg
set -euo pipefail
PROG="$(basename "$0")"
OUTPUT=""
TIMEOUT=5
DEFAULT=0
usage() {
cat <<EOF
Usage: $PROG [OPTION...]
Generate a GRUB configuration file.
-o, --output=FILE Write generated config to FILE [default: stdout]
--timeout=SECS Menu timeout in seconds [default: 5]
--set-default=N Default menu entry index [default: 0]
-h, --help Display this help and exit
-V, --version Print program version and exit
Examples:
# Preview generated config
$PROG
# Write to standard GRUB location
$PROG -o /boot/grub/grub.cfg
# Write to Red Bear OS recipe directory
$PROG -o local/recipes/core/grub/grub.cfg
EOF
exit 0
}
version() {
echo "$PROG (Red Bear OS) 2.12"
echo "Compatible with GNU GRUB grub-mkconfig interface"
exit 0
}
while [ $# -gt 0 ]; do
case "$1" in
-o|--output)
OUTPUT="$2"
shift 2
;;
--output=*)
OUTPUT="${1#--output=}"
shift
;;
--timeout=*)
TIMEOUT="${1#--timeout=}"
shift
;;
--timeout)
TIMEOUT="$2"
shift 2
;;
--set-default=*)
DEFAULT="${1#--set-default=}"
shift
;;
--set-default)
DEFAULT="$2"
shift 2
;;
-h|--help)
usage
;;
-V|--version)
version
;;
*)
echo "$PROG: unrecognized option '$1'" >&2
echo "Try '$PROG --help' for more information." >&2
exit 1
;;
esac
done
generate_config() {
cat <<GRUBCFG
# Generated by $PROG — $(date -Iseconds 2>/dev/null || date)
# Red Bear OS GRUB configuration — chainloads the Redox bootloader
set timeout=$TIMEOUT
set default=$DEFAULT
menuentry "Red Bear OS" {
chainloader /EFI/REDBEAR/redbear.efi
boot
}
menuentry "Reboot" {
reboot
}
menuentry "Shutdown" {
halt
}
GRUBCFG
}
if [ -n "$OUTPUT" ]; then
generate_config > "$OUTPUT"
else
generate_config
fi