blob: 0b3bfe7aefce13e41ba6a248701b247d7206c696 (
plain)
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
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
|
#!/bin/sh
#
# Shell command language linker
#
# Copyright (C) 2015, 2019 Patrick "P. J." McDermott
#
# 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 3 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.
#
# You should have received a copy of the GNU General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.
set -u
VERSION='0.3.0'
die()
{
local fmt="${1}"
shift 1
printf "shld: ${fmt}\n" "${@}" >&2
exit 2
}
link()
{
local make_executable="${1}"
local interpreter="${2}"
local entry_point="${3}"
local libs="${4}"
local output="${5}"
shift 5
local input=
# Open output file.
if ! exec 3>"${output}~"; then
die 'Cannot open file "%s"' "${output}~"
fi
# Write magic number and interpreter path.
if ${make_executable}; then
printf '#!%s\n' "${interpreter}" >&3
fi
# Write __init() function.
cat >&3 <<-'EOF'
__init_funcs=''
__init()
{
__init_funcs="${__init_funcs} ${1}"
}
EOF
# Read input files.
for input in "${@}"; do
if ! cat "${input}" >&3; then
die 'Cannot read file "%s"' "${input}"
fi
done
# Write __DT_NEEDED list and basic RTLD.
printf "__DT_NEEDED='%s'\n" "${libs}" >&3
cat >&3 <<-'EOF'
: ${SHLD_LIBRARY_PATH:=${LIBDATADIR}}
for __lib in ${__DT_NEEDED}; do
__found=false
IFS=':'
for __el in ${SHLD_LIBRARY_PATH}; do
if __f="$(cat "${__el}/${__lib}" 2>/dev/null)"
then
eval "${__f}"
__found=true
break
fi
done
unset IFS
if ! ${__found}; then
printf "%s: error while loading shell $(: \
)shared libraries: %s: cannot open $(: \
)shell shared object file\n" \
"${0}" "${__lib}" >&2
exit 127
fi
done
unset __lib __el __found __f
EOF
# Add call to init functions.
cat >&3 <<-'EOF'
unset IFS
for __func in ${__init_funcs}; do
${__func}
done
EOF
# Add call to entry point.
if ${make_executable}; then
printf '%s "${@}"\n' "${entry_point}" >&3
fi
# Close output file, make it executable, and set its name.
exec 3>&-
if ${make_executable}; then
if ! chmod a+x "${output}~"; then
die 'Cannot set mode of file "%s"' "${output}~"
fi
fi
if ! mv "${output}~" "${output}"; then
die 'Cannot rename file to "%s"' "${output}"
fi
}
usage()
{
printf 'Usage: %s [option ...] <file>...\n' "${0}"
}
help()
{
usage
cat <<EOF
Options:
-h Display this information
-V Display linker version information
-l <lib> Add <lib> to the list of libraries to load at run time
-I <interp> Make an executable and use <interp> as the interpreter for your
program, instead of the default of "/bin/sh"
-e <entry> Make an executable and use <entry> as the function for beginning
execution of your program, instead of the default of "main"
-o <output> Use <output> as the name of the program produced by shld, instead
of the default of "out.sh"
EOF
}
version()
{
cat <<EOF
shld ${VERSION}
Copyright (C) 2015 Patrick "P. J." McDermott
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>.
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.
EOF
}
main()
{
local opt=
local libs=''
local make_executable=false
local interpreter='/bin/sh'
local entry_point='main'
local output='out.sh'
while getopts 'hVl:I:e:o:' opt; do
case "${opt}" in
'h')
help
exit
;;
'V')
version
exit
;;
'l')
libs="${libs}${OPTARG} "
;;
'I')
interpreter="${OPTARG}"
make_executable=true
;;
'e')
entry_point="${OPTARG}"
make_executable=true
;;
'o')
output="${OPTARG}"
;;
esac
done
shift $(($OPTIND - 1))
if [ ${#} -lt 1 ]; then
usage >&2
exit 1
fi
link "${make_executable}" "${interpreter}" "${entry_point}" "${libs}" \
"${output}" "${@}"
}
main "${@}"
|
