1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180

#!/bin/bash
########################################################################
####  Script Name: smxi-stub
####  stub installer for smxi scripts
####  Only supports true Debian based distros.
####  version: 2.9
####  Date: 20 August 2009
########################################################################
####  Copyright (C) Harald Hope, sidux team members 2007-2009
####
####  This program is free software; you can redistribute it and/or modify it under
####  the terms of the GNU General Public License as published by the Free Software
####  Foundation; either version 2 of the License, or (at your option) any later version.
####
####  This program is distributed in the hope that it will be useful, but WITHOUT
####  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
####  FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
####
####  Get the full text of the GPL here: http://www.gnu.org/licenses/gpl.txt
########################################################################

# Please do not change the logic here, it makes it too hard to read linearly:
# [ ! -f somefile ] && do something is far easier to read than [ -f somefile ] || do something
# tempfile primary cleanup is now handled by called scripts, so no need to complicate this
# simple stub with the cleanup stuff. Now it just cleans up after itself each time.

# To get the full power and user friendliness for this stub installer
# rename it to: smxi
# place it in /usr/sbin, that is, as /usr/sbin/smxi, make it executable: chmod +x /usr/sbin/smxi
# add the following symbolic links in /usr/sbin pointing to /usr/sbin/smxi:
# ln -s /usr/sbin/smxi /usr/sbin/inxi
# ln -s /usr/sbin/smxi /usr/sbin/sgfxi
# ln -s /usr/sbin/smxi /usr/sbin/svmi
# because of how default $PATH works, /usr/sbin will always be checked first for the
# scripts, and if they are missing, this stub will download and execute them, otherwise
# the request will simply be passed along to /usr/local/bin location of actual scripts

# this will handle stub for any other script also
CALLER="$( basename $0 )"
PREFIX='/usr/local/bin/'
DOWNLOAD_URL=''
DOWNLOAD_URL_INXI='http://inxi.googlecode.com/svn/trunk/'
DOWNLOAD_URL_SGFXI='http://smxi.org/sg/'
DOWNLOAD_URL_SMXI='http://smxi.org/sm/'
DOWNLOAD_URL_SVMI='http://smxi.org/sv/'
# Do  not create temp file here. It will create masses of temp files over time.
FILE_TEMP_NAME='' # will handle failed downloads
# this is the tester for ##**EOF**## endings present in scripts, change this
# if you want to extend this stub to other scripts, smxi/svmi/inxi/sgfxi all use this
SCRIPT_EOF='##\*\*EOF\*\*##'

# args: $1 - error number; $2 - extra data
error_handler()
{
	local message=''
	case $1 in
		1)	message='You must be root to run this script!'
			;;
		2)	message='Failed to download script properly. The file is empty!'
			;;
		3)	message="$PREFIX$SCRIPT not executable!"
			;;
		4)	message="Script download exited with errors.\nThe following download url failed with wget error: $2/n$DOWNLOAD_URL$SCRIPT"
			;;
		5)	message='Unknown script requested.'
			;;
		6)	message='Failed to download script. The downloaded file does not exist!'
			;;
		7)	message="$PREFIX$SCRIPT exec command failed with error number: $2\nDeleting problem file. Please try again."
			# this will handle, I think, partial, incomplete, downloads, that are not null
			if [ -f "$PREFIX$SCRIPT" ];then
				rm -f "$PREFIX$SCRIPT"
			fi
			;;
		8)	message='Failed to download script properly. The file is corrupted!'
			;;
		*)	message='Unknown error, exiting now.'
			;;
	esac
	echo -e "Error No: $1 - $message"
	# cleanup the temp file if error
	if [ -f "$FILE_TEMP_NAME" ];then
		rm -f "$FILE_TEMP_NAME"
	fi
	exit $1
}

# set the SCRIPT/DOWNLOAD_URL/SCRIPT_EOFvalues
case $CALLER in
	sgfxi)
		SCRIPT="$CALLER"
		DOWNLOAD_URL=$DOWNLOAD_URL_SGFXI
		;;
	smxi)
		SCRIPT="$CALLER"
		DOWNLOAD_URL=$DOWNLOAD_URL_SMXI
		;;
	svmi)
		SCRIPT="$CALLER"
		DOWNLOAD_URL=$DOWNLOAD_URL_SVMI
		;;
	inxi)
		SCRIPT="$CALLER"
		DOWNLOAD_URL=$DOWNLOAD_URL_INXI
		;;
	*)
		error_handler 5
		;;
esac

# this handles that annoying null file thing. Because -s is ambiguous, I added a -f check
# as well. Delete all existing null files. This test must be first. This won't handle incomplete
# downloads, but it will help a bit. This also avoids a file does not exist error
if [ -f "$PREFIX$SCRIPT" -a ! -s "$PREFIX$SCRIPT" ];then
	rm -f "$PREFIX$SCRIPT"
fi

# now that null files are removed, we can safely use the -x test. Note: be very careful
# relying on -x as a test, null files can have the exec bit set... that's bash for you...
# if $SCRIPT exists, it will handle the root tests. Root tests cannot
# be run first because they kill the -h help function
if [ -x "$PREFIX$SCRIPT" ];then
	# I'm just going to put a test for basically everything that can go wrong
	# If we're lucky, this will handle partial or incomplete downloads that are not null
	exec "$PREFIX$SCRIPT" "$@" || error_handler 7 "$?"
else
	# only in case of requirement to download script do root test, and just exit
	# if not root, anything else is counterintuitive I think for users.
	if [ "$( id -u )" -ne 0 ];then
		error_handler 1
	fi

	# if and only if file does not exist and user is root do we make the temp file
	FILE_TEMP_NAME="$( mktemp -p $PREFIX $CALLER.XXXXXXXXXX )"
	# now we'll use a simple -f test since the null case is already handled. We are not
	# downloading to overwrite existing file, but to temp file, which we then test for null
	# -O is risky here too because failed downloads create a null file automatically.
	if [ ! -f "$PREFIX$SCRIPT" ];then
		wget -q -O "$FILE_TEMP_NAME" "$DOWNLOAD_URL$SCRIPT" || error_handler 4 "$?"
	fi
	
	# the primary test is to test for file corruption, if the new file doesn't have
	# the EOF value, it is by definition corrupted. After that some simple tests.
	#  -s is prefered over -f because sometimes downloads fail and leave null size file
	# we're taking the temp file, testing it for null, then mv to correct file. Please do
	# not mess with these tests at all unless you can make them even more robust. No -f
	# is required because if wget exits with error then script exits. And if no error,
	# file will be null or existent and not null. I am adding another -f test here because
	# wget is so buggy I simply cannot predict its failure behaviors at all.
	if [ ! -e "$FILE_TEMP_NAME" ];then
		error_handler 6
	elif [ ! -s "$FILE_TEMP_NAME" ];then
 		error_handler 2
 	# then test for eof marker in files, this is basically foolproof
	elif [ -z "$( grep -si "$SCRIPT_EOF" $FILE_TEMP_NAME )" ];then
		error_handler 8
# 	# if exists and not null
	# I'm being extra careful here, there have been too many problems with this simple
	# stuff... wget needs to be fixed to handle failed downloads better... what is  missing
	# is a null file test, as opposed to exists AND null.
	elif [ -s "$FILE_TEMP_NAME" ];then
		# now that the file exists and is not null
		mv -f $FILE_TEMP_NAME $PREFIX$SCRIPT

		# make executable if not
		if [ ! -x "$PREFIX$SCRIPT" ];then
			chmod +x "$PREFIX$SCRIPT"
		fi

		# then run it with an error handler for unknown weirdness which I'm sure will appear.
		if [ -x "$PREFIX$SCRIPT" ];then
			# I'm just going to put a test for basically everything that can go wrong
			# If we're lucky, this will handle partial or incomplete downloads that are not null
			exec "$PREFIX$SCRIPT" "$@" || error_handler 7 "$?"
		else
			error_handler 3
		fi
	fi
fi