mirror of
https://github.com/NixOS/nixpkgs.git
synced 2024-12-01 18:12:46 +00:00
261 lines
8.5 KiB
Bash
261 lines
8.5 KiB
Bash
# Assert that FILE exists and is executable
|
||
#
|
||
# assertExecutable FILE
|
||
assertExecutable() {
|
||
local file="$1"
|
||
[[ -f "$file" && -x "$file" ]] || \
|
||
die "Cannot wrap '$file' because it is not an executable file"
|
||
}
|
||
|
||
# Generate a binary executable wrapper for wrapping an executable.
|
||
# The binary is compiled from generated C-code using gcc.
|
||
# makeBinaryWrapper EXECUTABLE OUT_PATH ARGS
|
||
|
||
# ARGS:
|
||
# --argv0 NAME : set name of executed process to NAME
|
||
# (otherwise it’s called …-wrapped)
|
||
# --set VAR VAL : add VAR with value VAL to the executable’s
|
||
# environment
|
||
# --set-default VAR VAL : like --set, but only adds VAR if not already set in
|
||
# the environment
|
||
# --unset VAR : remove VAR from the environment
|
||
# --add-flags FLAGS : add FLAGS to invocation of executable
|
||
|
||
# --prefix ENV SEP VAL : suffix/prefix ENV with VAL, separated by SEP
|
||
# --suffix
|
||
|
||
# To troubleshoot a binary wrapper after you compiled it,
|
||
# use the `strings` command or open the binary file in a text editor.
|
||
makeBinaryWrapper() {
|
||
assertExecutable "$1"
|
||
makeDocumentedCWrapper "$1" "${@:3}" | gcc -Os -x c -o "$2" -
|
||
}
|
||
|
||
# Syntax: wrapProgramBinary <PROGRAM> <MAKE-WRAPPER FLAGS...>
|
||
wrapProgramBinary() {
|
||
local prog="$1"
|
||
local hidden
|
||
|
||
assertExecutable "$prog"
|
||
|
||
hidden="$(dirname "$prog")/.$(basename "$prog")"-wrapped
|
||
while [ -e "$hidden" ]; do
|
||
hidden="${hidden}_"
|
||
done
|
||
mv "$prog" "$hidden"
|
||
# Silence warning about unexpanded $0:
|
||
# shellcheck disable=SC2016
|
||
makeBinaryWrapper "$hidden" "$prog" --argv0 '$0' "${@:2}"
|
||
}
|
||
|
||
# Generate source code for the wrapper in such a way that the wrapper source code
|
||
# will still be readable even after compilation
|
||
# makeDocumentedCWrapper EXECUTABLE ARGS
|
||
# ARGS: same as makeBinaryWrapper
|
||
makeDocumentedCWrapper() {
|
||
local src docs
|
||
src=$(makeCWrapper "$@")
|
||
docs=$(documentationString "$src")
|
||
printf '%s\n\n' "$src"
|
||
printf '%s\n' "$docs"
|
||
}
|
||
|
||
# makeCWrapper EXECUTABLE ARGS
|
||
# ARGS: same as makeBinaryWrapper
|
||
makeCWrapper() {
|
||
local argv0 n params cmd main flagsBefore flags executable params length
|
||
local uses_prefix uses_suffix uses_concat3 uses_assert
|
||
executable=$(escapeStringLiteral "$1")
|
||
params=("$@")
|
||
length=${#params[*]}
|
||
for ((n = 1; n < length; n += 1)); do
|
||
p="${params[n]}"
|
||
case $p in
|
||
--set)
|
||
cmd=$(setEnv "${params[n + 1]}" "${params[n + 2]}")
|
||
main="$main $cmd"$'\n'
|
||
n=$((n + 2))
|
||
[ $n -ge "$length" ] && main="$main #error makeCWrapper: $p takes 2 arguments"$'\n'
|
||
;;
|
||
--set-default)
|
||
cmd=$(setDefaultEnv "${params[n + 1]}" "${params[n + 2]}")
|
||
main="$main $cmd"$'\n'
|
||
n=$((n + 2))
|
||
[ $n -ge "$length" ] && main="$main #error makeCWrapper: $p takes 2 arguments"$'\n'
|
||
;;
|
||
--unset)
|
||
cmd=$(unsetEnv "${params[n + 1]}")
|
||
main="$main $cmd"$'\n'
|
||
n=$((n + 1))
|
||
[ $n -ge "$length" ] && main="$main #error makeCWrapper: $p takes 1 argument"$'\n'
|
||
;;
|
||
--prefix)
|
||
cmd=$(setEnvPrefix "${params[n + 1]}" "${params[n + 2]}" "${params[n + 3]}")
|
||
main="$main $cmd"$'\n'
|
||
uses_prefix=1
|
||
uses_concat3=1
|
||
uses_assert=1
|
||
n=$((n + 3))
|
||
[ $n -ge "$length" ] && main="$main #error makeCWrapper: $p takes 3 arguments"$'\n'
|
||
;;
|
||
--suffix)
|
||
cmd=$(setEnvSuffix "${params[n + 1]}" "${params[n + 2]}" "${params[n + 3]}")
|
||
main="$main $cmd"$'\n'
|
||
uses_suffix=1
|
||
uses_concat3=1
|
||
uses_assert=1
|
||
n=$((n + 3))
|
||
[ $n -ge "$length" ] && main="$main #error makeCWrapper: $p takes 3 arguments"$'\n'
|
||
;;
|
||
--add-flags)
|
||
flags="${params[n + 1]}"
|
||
flagsBefore="$flagsBefore $flags"
|
||
uses_assert=1
|
||
n=$((n + 1))
|
||
[ $n -ge "$length" ] && main="$main #error makeCWrapper: $p takes 1 argument"$'\n'
|
||
;;
|
||
--argv0)
|
||
argv0=$(escapeStringLiteral "${params[n + 1]}")
|
||
n=$((n + 1))
|
||
[ $n -ge "$length" ] && main="$main #error makeCWrapper: $p takes 1 argument"$'\n'
|
||
;;
|
||
*) # Using an error macro, we will make sure the compiler gives an understandable error message
|
||
main="$main #error makeCWrapper: Uknown argument ${p}"$'\n'
|
||
;;
|
||
esac
|
||
done
|
||
# shellcheck disable=SC2086
|
||
[ -z "$flagsBefore" ] || main="$main"${main:+$'\n'}$(addFlags $flagsBefore)$'\n'$'\n'
|
||
main="$main argv[0] = \"${argv0:-${executable}}\";"$'\n'
|
||
main="$main return execv(\"${executable}\", argv);"$'\n'
|
||
|
||
printf '%s\n' "#include <unistd.h>"
|
||
printf '%s\n' "#include <stdlib.h>"
|
||
[ -z "$uses_concat3" ] || printf '%s\n' "#include <string.h>"
|
||
[ -z "$uses_assert" ] || printf '%s\n' "#include <assert.h>"
|
||
[ -z "$uses_concat3" ] || printf '\n%s\n' "$(concat3Fn)"
|
||
[ -z "$uses_prefix" ] || printf '\n%s\n' "$(setEnvPrefixFn)"
|
||
[ -z "$uses_suffix" ] || printf '\n%s\n' "$(setEnvSuffixFn)"
|
||
printf '\n%s' "int main(int argc, char **argv) {"
|
||
printf '\n%s' "$main"
|
||
printf '%s\n' "}"
|
||
}
|
||
|
||
addFlags() {
|
||
local result n flag flags var
|
||
var="argv_tmp"
|
||
flags=("$@")
|
||
for ((n = 0; n < ${#flags[*]}; n += 1)); do
|
||
flag=$(escapeStringLiteral "${flags[$n]}")
|
||
result="$result ${var}[$((n+1))] = \"$flag\";"$'\n'
|
||
done
|
||
printf ' %s\n' "char **$var = malloc(sizeof(*$var) * ($((n+1)) + argc));"
|
||
printf ' %s\n' "assert($var != NULL);"
|
||
printf ' %s\n' "${var}[0] = argv[0];"
|
||
printf '%s' "$result"
|
||
printf ' %s\n' "for (int i = 1; i < argc; ++i) {"
|
||
printf ' %s\n' " ${var}[$n + i] = argv[i];"
|
||
printf ' %s\n' "}"
|
||
printf ' %s\n' "${var}[$n + argc] = NULL;"
|
||
printf ' %s\n' "argv = $var;"
|
||
}
|
||
|
||
# prefix ENV SEP VAL
|
||
setEnvPrefix() {
|
||
local env sep val
|
||
env=$(escapeStringLiteral "$1")
|
||
sep=$(escapeStringLiteral "$2")
|
||
val=$(escapeStringLiteral "$3")
|
||
printf '%s' "set_env_prefix(\"$env\", \"$sep\", \"$val\");"
|
||
}
|
||
|
||
# suffix ENV SEP VAL
|
||
setEnvSuffix() {
|
||
local env sep val
|
||
env=$(escapeStringLiteral "$1")
|
||
sep=$(escapeStringLiteral "$2")
|
||
val=$(escapeStringLiteral "$3")
|
||
printf '%s' "set_env_suffix(\"$env\", \"$sep\", \"$val\");"
|
||
}
|
||
|
||
# setEnv KEY VALUE
|
||
setEnv() {
|
||
local key value
|
||
key=$(escapeStringLiteral "$1")
|
||
value=$(escapeStringLiteral "$2")
|
||
printf '%s' "putenv(\"$key=$value\");"
|
||
}
|
||
|
||
# setDefaultEnv KEY VALUE
|
||
setDefaultEnv() {
|
||
local key value
|
||
key=$(escapeStringLiteral "$1")
|
||
value=$(escapeStringLiteral "$2")
|
||
printf '%s' "setenv(\"$key\", \"$value\", 0);"
|
||
}
|
||
|
||
# unsetEnv KEY
|
||
unsetEnv() {
|
||
local key
|
||
key=$(escapeStringLiteral "$1")
|
||
printf '%s' "unsetenv(\"$key\");"
|
||
}
|
||
|
||
# Put the entire source code into const char* SOURCE_CODE to make it readable after compilation.
|
||
# documentationString SOURCE_CODE
|
||
documentationString() {
|
||
local docs
|
||
docs=$(escapeStringLiteral $'\n----------\n// This binary wrapper was compiled from the following generated C-code:\n'"$1"$'\n----------\n')
|
||
printf '%s' "const char * SOURCE_CODE = \"$docs\";"
|
||
}
|
||
|
||
# Makes it safe to insert STRING within quotes in a C String Literal.
|
||
# escapeStringLiteral STRING
|
||
escapeStringLiteral() {
|
||
local result
|
||
result=${1//$'\\'/$'\\\\'}
|
||
result=${result//\"/'\"'}
|
||
result=${result//$'\n'/"\n"}
|
||
result=${result//$'\r'/"\r"}
|
||
printf '%s' "$result"
|
||
}
|
||
|
||
concat3Fn() {
|
||
printf '%s' "\
|
||
char *concat3(char *x, char *y, char *z) {
|
||
int xn = strlen(x);
|
||
int yn = strlen(y);
|
||
int zn = strlen(z);
|
||
char *res = malloc(sizeof(*res)*(xn + yn + zn + 1));
|
||
assert(res != NULL);
|
||
strncpy(res, x, xn);
|
||
strncpy(res + xn, y, yn);
|
||
strncpy(res + xn + yn, z, zn);
|
||
res[xn + yn + zn] = '\0';
|
||
return res;
|
||
}
|
||
"
|
||
}
|
||
|
||
setEnvPrefixFn() {
|
||
printf '%s' "\
|
||
void set_env_prefix(char *env, char *sep, char *val) {
|
||
char *existing = getenv(env);
|
||
if (existing) val = concat3(val, sep, existing);
|
||
setenv(env, val, 1);
|
||
if (existing) free(val);
|
||
}
|
||
"
|
||
}
|
||
|
||
setEnvSuffixFn() {
|
||
printf '%s' "\
|
||
void set_env_suffix(char *env, char *sep, char *val) {
|
||
char *existing = getenv(env);
|
||
if (existing) val = concat3(existing, sep, val);
|
||
setenv(env, val, 1);
|
||
if (existing) free(val);
|
||
}
|
||
"
|
||
}
|