[PATCH v4 02/13] scripts: port make-gpt.sh to bash

[Demi Marie Obenour <demiobenour@gmail.com>]

Future changes will be using bash-specific features.  Use bash-specific
code for this.  Also add some error checks.

No other functional change intended.

Signed-off-by: Demi Marie Obenour <demiobenour@gmail.com>
---
Changes since v4:
- Improve commit message.

Changes since v2:

- Do not use wrapper script.
- Make script non-executable.
- Invoke script as 'bash FILE' to work around /usr/bin/env not working
  during a Nix build.
---
 host/initramfs/Makefile |  4 ++--
 host/rootfs/Makefile    |  2 +-
 img/app/Makefile        |  2 +-
 release/live/Makefile   |  2 +-
 scripts/make-gpt.sh     | 20 ++++++++++----------
 vm/sys/net/Makefile     |  2 +-
 6 files changed, 16 insertions(+), 16 deletions(-)

diff --git a/host/initramfs/Makefile b/host/initramfs/Makefile
index f27f5e07c4707914962197b4fea8f385729370aa..2304b0885a152d8a659dddcc58f948d096034e2d 100644
--- a/host/initramfs/Makefile
+++ b/host/initramfs/Makefile
@@ -36,7 +36,7 @@ build/mountpoints:
 	find build/mountpoints -mindepth 1 -exec touch -d @0 {} ';'
 
 build/live.img: ../../scripts/format-uuid.sh ../../scripts/make-gpt.sh ../../scripts/sfdisk-field.awk $(ROOT_FS_IMAGES)
-	../../scripts/make-gpt.sh $@.tmp \
+	bash ../../scripts/make-gpt.sh $@.tmp \
 	    $(ROOT_FS_VERITY):verity:$$(../../scripts/format-uuid.sh "$$(dd if=$(ROOT_FS_VERITY_ROOTHASH) bs=32 skip=1 count=1 status=none)") \
 	    $(ROOT_FS_IMAGE):root:$$(../../scripts/format-uuid.sh "$$(head -c 32 $(ROOT_FS_VERITY_ROOTHASH))")
 	mv $@.tmp $@
@@ -45,7 +45,7 @@ build/loop.tar: build/live.img
 	$(TAR) -cf $@ build/live.img
 
 build/loop.img: ../../scripts/make-gpt.sh ../../scripts/sfdisk-field.awk build/loop.ext4
-	../../scripts/make-gpt.sh $@.tmp \
+	bash ../../scripts/make-gpt.sh $@.tmp \
 	    build/loop.ext4:56a3bbc3-aefa-43d9-a64d-7b3fd59bbc4e
 	mv $@.tmp $@
 
diff --git a/host/rootfs/Makefile b/host/rootfs/Makefile
index 4cb048ac08b3265b0435d6ff6fc612a58c169ce9..f45758041f2f682618cb0f9e54e5a74f0b49874e 100644
--- a/host/rootfs/Makefile
+++ b/host/rootfs/Makefile
@@ -93,7 +93,7 @@ clean:
 .PHONY: clean
 
 build/live.img: ../../scripts/format-uuid.sh ../../scripts/make-gpt.sh ../../scripts/sfdisk-field.awk build/verity-timestamp $(ROOT_FS_IMAGES)
-	../../scripts/make-gpt.sh $@.tmp \
+	bash ../../scripts/make-gpt.sh $@.tmp \
 	    $(ROOT_FS_VERITY):verity:$$(../../scripts/format-uuid.sh "$$(dd if=$(ROOT_FS_VERITY_ROOTHASH) bs=32 skip=1 count=1 status=none)") \
 	    $(ROOT_FS_IMAGE):root:$$(../../scripts/format-uuid.sh "$$(head -c 32 $(ROOT_FS_VERITY_ROOTHASH))")
 	mv $@.tmp $@
diff --git a/img/app/Makefile b/img/app/Makefile
index 48eba871339d314479f730101246ace3fa39e2db..f16c2df1b90bbec6750f2980da4dbaf49c9cb0ea 100644
--- a/img/app/Makefile
+++ b/img/app/Makefile
@@ -26,7 +26,7 @@ $(imgdir)/appvm/vmlinux: $(KERNEL)
 
 $(imgdir)/appvm/blk/root.img: ../../scripts/make-gpt.sh ../../scripts/sfdisk-field.awk build/rootfs.erofs
 	mkdir -p $$(dirname $@)
-	../../scripts/make-gpt.sh $@.tmp \
+	bash ../../scripts/make-gpt.sh $@.tmp \
 	    build/rootfs.erofs:root:5460386f-2203-4911-8694-91400125c604:root
 	mv $@.tmp $@
 
diff --git a/release/live/Makefile b/release/live/Makefile
index b37ccce42feb3ac7e8ce4faf96a67902b55be808..c712db3727b7008105388a278552fd3d81eb3b4c 100644
--- a/release/live/Makefile
+++ b/release/live/Makefile
@@ -10,7 +10,7 @@ DTBS ?= build/empty
 dest = build/live.img
 
 $(dest): ../../scripts/format-uuid.sh ../../scripts/make-gpt.sh ../../scripts/sfdisk-field.awk build/boot.fat $(ROOT_FS_IMAGES)
-	../../scripts/make-gpt.sh $@.tmp \
+	bash ../../scripts/make-gpt.sh $@.tmp \
 	    build/boot.fat:c12a7328-f81f-11d2-ba4b-00a0c93ec93b \
 	    $(ROOT_FS_VERITY):verity:$$(../../scripts/format-uuid.sh "$$(dd if=$(ROOT_FS_VERITY_ROOTHASH) bs=32 skip=1 count=1 status=none)") \
 	    $(ROOT_FS_IMAGE):root:$$(../../scripts/format-uuid.sh "$$(head -c 32 $(ROOT_FS_VERITY_ROOTHASH))")
diff --git a/scripts/make-gpt.sh b/scripts/make-gpt.sh
old mode 100755
new mode 100644
index 96f0d2c8494c093558c0e32e7e920b569bb078ef..0ae3d0005e5ae7d6214270fedb2fafb0a7064cf5
--- a/scripts/make-gpt.sh
+++ b/scripts/make-gpt.sh
@@ -1,11 +1,11 @@
-#!/bin/sh -eu
-#
+#!/usr/bin/env -S bash --
 # SPDX-FileCopyrightText: 2021-2023 Alyssa Ross <hi@alyssa.is>
 # SPDX-FileCopyrightText: 2022 Unikie
 # SPDX-License-Identifier: EUPL-1.2+
 #
-# usage: make-gpt.sh GPT_PATH PATH:PARTTYPE[:PARTUUID[:PARTLABEL]]...
+# usage: bash make-gpt.sh GPT_PATH PATH:PARTTYPE[:PARTUUID[:PARTLABEL]]...
 
+set -xeuo pipefail
 ONE_MiB=1048576
 
 # Prints the number of 1MiB blocks required to store the file named
@@ -40,16 +40,15 @@ scriptsDir="$(dirname "$0")"
 out="$1"
 shift
 
-nl='
-'
 table="label: gpt"
 
 # Keep 1MiB free at the start, and 1MiB free at the end.
 gptBytes=$((ONE_MiB * 2))
 for partition; do
-	sizeMiB="$(sizeMiB "$(partitionPath "$partition")")"
-	table="$table${nl}size=${sizeMiB}MiB,$(awk -f "$scriptsDir/sfdisk-field.awk" -v partition="$partition")"
-	gptBytes="$((gptBytes + sizeMiB * ONE_MiB))"
+	partitionPath=$(partitionPath "$partition")
+	sizeMiB=$(sizeMiB "$partitionPath")
+	table+=$'\n'"size=${sizeMiB}MiB,$(awk -f "$scriptsDir/sfdisk-field.awk" -v partition="$partition")"
+	gptBytes=$((gptBytes + sizeMiB * ONE_MiB))
 done
 
 rm -f "$out"
@@ -60,6 +59,7 @@ EOF
 
 n=0
 for partition; do
-	fillPartition "$out" "$n" "$(partitionPath "$partition")"
-	n="$((n + 1))"
+	partitionPath=$(partitionPath "$partition")
+	fillPartition "$out" "$n" "$partitionPath"
+	n=$((n + 1))
 done
diff --git a/vm/sys/net/Makefile b/vm/sys/net/Makefile
index d71c2325eff3bae921f33c61f799846d35e401c2..e403d697d90c0021a7a8d1dbc1553cfbda74a117 100644
--- a/vm/sys/net/Makefile
+++ b/vm/sys/net/Makefile
@@ -25,7 +25,7 @@ $(vmdir)/netvm/vmlinux: $(KERNEL)
 
 $(vmdir)/netvm/blk/root.img: ../../../scripts/make-gpt.sh ../../../scripts/sfdisk-field.awk build/rootfs.erofs
 	mkdir -p $$(dirname $@)
-	../../../scripts/make-gpt.sh $@.tmp \
+	bash ../../../scripts/make-gpt.sh $@.tmp \
 	    build/rootfs.erofs:root:ea21da27-0391-48da-9235-9d2ab2ca7844:root
 	mv $@.tmp $@
 

-- 
2.52.0