fileset

commit 4b5aa00a59b0bfae501233813f47e23d4087d15d
parent f05525714a786a7770ee50e643968c7e935c7b28
Author: Jan Pobrislo <ccx@webprojekty.cz>
Date:   Fri,  2 Jun 2017 19:02:58 +0200

fix devices in fslist, WIP cpio2fs
Diffstat:
A
bin/cpio2fs
 | 
132
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
M
bin/fslist
 | 
2
+-

2 files changed, 133 insertions(+), 1 deletion(-)
diff --git a/bin/cpio2fs b/bin/cpio2fs
@@ -0,0 +1,132 @@
+#!/bin/zsh
+# Reads cpio archive and emits fileset file
+setopt no_unset warn_create_global no_multibyte
+
+typeset -gA cpio_struct ftypes hardlinks
+typeset -g delim filename ftype fmode
+
+ftypes=(  # convert hex type to mnemonic character
+	C  s  # socket
+	c  s
+	A  l  # symbolic link
+	a  l
+	8  f  # regular file
+	6  b  # block device
+	4  d  # directory
+	2  u  # character device
+	1  p  # FIFO
+)
+
+
+### Defaults for options passed by env {{{1
+
+# TODO: make into command-line arguments
+: ${compact:=1}
+: ${print_m:=1}
+: ${print_o:=1}
+: ${print_c:=1}
+if (($+commands[file])) && (($+commands[base64])); then
+	: ${print_b:=1}
+else
+	: ${print_b:=0}
+	if (($+commands[file])) && (($+commands[xxd])); then
+		: ${print_x:=1}
+	fi
+fi
+: ${print_x:=0}
+
+
+### Generic helpers {{{1
+
+die() {
+	printf '%s\n' "$@"
+	exit 1
+}
+
+
+### cpio header reader functions {{{1
+
+read_newc() {
+	local field
+	for field size in
+		c_magic 6 \
+		c_dev 6 \
+		c_ino 6 \
+		c_mode 6 \
+		c_uid 6 \
+		c_gid 6 \
+		c_nlink 6 \
+		c_rdev 6 \
+		c_mtime 11 \
+		c_namesize 6 \
+		c_filesize 11
+	do
+		read -k size || die "Short read of cpio archive header"
+		[[ $REPLY =~ '^[0-7]{'$size'}$' ]] \
+			|| die "Invalid octal header value: ${(qqq)REPLY}"
+		cpio_struct[$field]=$(( [##8] $REPLY ))
+	done
+	cpio_struct[rdev_major]=$(( $s[rdev] >> 8 ))
+	cpio_struct[rdev_minor]=$(( $s[rdev] & 255 ))
+}
+
+read_newc() {
+	local field
+	cpio_struct=( )
+	for field in c_ino c_mode c_uid c_gid c_nlink c_mtime c_filesize \
+		c_devmajor c_devminor c_rdevmajor c_rdevminor c_namesize c_check
+	do
+		read -k 8 || die "Short read of cpio archive header"
+		[[ $REPLY =~ '^[0-7a-fA-F]{8}$' ]] \
+			|| die "Invalid hexadecimal header value: ${(qqq)REPLY}"
+		cpio_struct[$field]=$(( [##16] $REPLY ))
+	done
+	cpio_struct[c_dev]=$cpio_struct[c_devmajor]:$cpio_struct[c_devminor]
+}
+
+read_cpio_header() {
+	read -k 6 || return $?
+	cpio_struct=( c_magic $REPLY )
+	case "$c_magic" in
+		(070707)  # oldc (aka Portable ASCII Format)
+			read_oldc_header;;
+		(070701)  # newc (aka New ASCII Format)
+			read_newc_header;;
+		(070702)  # crc (aka New CRC Format) is same in structure as newc
+			read_newc_header;;
+		(*)
+			die "Unknown cpio format number: ${(qqq)c_magic}";;
+	esac
+}
+
+### FileSet writer functions {{{1
+
+statement() {
+	# start on new line for multiline statements - more readable
+	if [[ -n delim && $1 == *$'\n'* ]]; then
+		delim=$'\n'
+	fi
+	printf '%s%s' $delim ${1//$'\n'/$'\n\t'}
+	delim=${2:-$'\t'}
+}
+
+statement_end() {
+	printf '\n'
+	delim=''
+}
+
+
+process_file() {
+	local filename ftype fmode t
+	filename="$(dd bs=$cpio_struct[c_namesize] count=1 | tr -d '\0')" \
+		|| die "Could not read filename"
+	ftype=$(( [##16] $cpio_struct[c_mode] >> 12 ))
+	fmode=$(( [##8] $cpio_struct[c_mode] & 8#7777 ))
+	t=$ftypes[$ftype]
+}
+
+
+### Mainloop {{{1
+while read_cpio_header; do
+	process_file
+done
diff --git a/bin/fslist b/bin/fslist
@@ -88,7 +88,7 @@ for fname in $fnames; do
 		fi
 	fi
 
-	if [[ $t == [BC] ]]; then
+	if [[ $t == [bu] ]]; then
 		statement $t$(( $s[rdev] >> 8 )):$(( $s[rdev] & 255 ))
 	elif [[ $t == l ]]; then
 		statement $'l\t'$s[link] $'\t'