Add a pre-extract script (issue #242)

README.md

@@ -98,6 +98,7 @@ makeself.sh [args] archive_dir file_name label startup_script [script_args]
     * **`--follow`** : Follow the symbolic links inside of the archive directory, i.e. store the files that are being pointed to instead of the links themselves.
     * **`--append`** _(new in 2.1.x)_: Append data to an existing archive, instead of creating a new one. In this mode, the settings from the original archive are reused (compression type, label, embedded script), and thus don't need to be specified again on the command line.
     * **`--header`** : Makeself uses a separate file to store the header stub, called `makeself-header.sh`. By default, it is assumed that it is stored in the same location as makeself.sh. This option can be used to specify its actual location if it is stored someplace else.
+    * **`--preextract`** : Specify a pre-extraction script. The script is executed with the same environment and initial `script_args` as `startup_script`.
     * **`--cleanup`** : Specify a script that is run when execution is interrupted or finishes successfully. The script is executed with the same environment and initial `script_args` as `startup_script`. 
     * **`--copy`** : Upon extraction, the archive will first extract itself to a temporary directory. The main application of this is to allow self-contained installers stored in a Makeself archive on a CD, when the installer program will later need to unmount the CD and allow a new one to be inserted. This prevents "Filesystem busy" errors for installers that span multiple CDs.
     * **`--nox11`** : Disable the automatic spawning of a new terminal in X11.

makeself-header.sh

@@ -24,6 +24,7 @@ scriptargs="$SCRIPTARGS"
 cleanup_script="${CLEANUP_SCRIPT}"
 licensetxt="$LICENSE"
 helpheader="${HELPHEADER}"
+preextract="${PREEXTRACT_ENCODED}"
 targetdir="$archdirname"
 filesizes="$filesizes"
 totalsize="$totalsize"
@@ -164,7 +165,8 @@ Makeself version $MS_VERSION
   \$0 --lsm    Print embedded lsm entry (or no LSM)
   \$0 --list   Print the list of files in the archive
   \$0 --check  Checks integrity of the archive
-  \$0 --verify-sig key Verify signature agains a provided key id
+  \$0 --verify-sig key Verify signature against a provided key id
+  \$0 --show-preextract Print pre-extraction script
 
  2) Running \$0 :
   \$0 [options] [--] [additional arguments to embedded script]
@@ -305,6 +307,31 @@ MS_Check()
     fi
 }
 
+MS_Preextract()
+{
+    if test -z "\$preextract"; then
+        return
+    elif test x"\$verbose" = xy; then
+        MS_Printf "About to run pre-extraction script ... Proceed ? [Y/n] "
+        read yn
+        if test x"\$yn" = xn; then
+            eval \$finish; exit 1
+        fi
+    fi
+
+    prescript=\`mktemp "\$tmpdir/XXXXXX"\`
+    echo "\$preextract" | base64 -d > "\$prescript"
+    chmod a+x "\$prescript"
+
+    (cd "\$tmpdir"; eval "\"\$prescript\" \$scriptargs \"\\\$@\""); res=\$?
+
+    rm -f "\$prescript"
+    if test \$res -ne 0; then
+        echo "Pre-extraction script returned an error code (\$res)" >&2
+        eval \$finish; exit 1
+    fi
+}
+
 MS_Decompress()
 {
     if test x"\$decrypt_cmd" != x""; then
@@ -456,13 +483,22 @@ EOLSM
     shift 2 || { MS_Help; exit 1; }
     MS_Verify_Sig "\$0"
     ;;
+    --show-preextract)
+    if test -z "\$preextract"; then
+        echo "Pre-extraction script is not provided." >&2
+        exit 1
+    fi
+    echo "\$preextract" | base64 -d
+    exit 0
+    ;;
     --confirm)
 	verbose=y
 	shift
 	;;
 	--noexec)
 	script=""
     cleanup_script=""
+    preextract=""
 	shift
 	;;
     --noexec-cleanup)
@@ -623,6 +659,8 @@ if test x"\$SETUP_NOCHECK" != x1; then
 fi
 offset=\`head -n "\$skip" "\$0" | wc -c | sed "s/ //g"\`
 
+MS_Preextract "\$@"
+
 if test x"\$verbose" = xy; then
 	MS_Printf "About to extract $USIZE KB in \$tmpdir ... Proceed ? [Y/n] "
 	read yn

makeself.1

@@ -105,6 +105,9 @@ Specify location of the header script.
 .B --help-header file
 Add a header to the archive's help output.
 .TP
+.B --preextract file
+Specify a pre-extraction script.
+.TP
 .B --cleanup file
 Specify a cleanup script that executes on interrupt and when finished successfully.
 .TP

makeself.sh

@@ -93,6 +93,7 @@ MS_Usage()
     echo "    --nocrc            : Don't calculate a CRC for archive"
     echo "    --sha256           : Compute a SHA256 checksum for the archive"
     echo "    --header file      : Specify location of the header script"
+    echo "    --preextract file  : Specify a pre-extraction script"
     echo "    --cleanup file     : Specify a cleanup script that executes on interrupt and when finished successfully."
     echo "    --follow           : Follow the symlinks in the archive"
     echo "    --noprogress       : Do not show the progress during the decompression"
@@ -311,6 +312,12 @@ do
 	HEADER="$2"
     shift 2 || { MS_Usage; exit 1; }
 	;;
+    --preextract)
+    preextract_file="$2"
+    shift 2 || { MS_Usage; exit 1; }
+    test -r "$preextract_file" || { echo "Unable to open pre-extraction script: $preextract_file" >&2; exit 1; }
+    PREEXTRACT_ENCODED=`base64 "$preextract_file"`
+    ;;
     --cleanup)
     CLEANUP_SCRIPT="$2"
     shift 2 || { MS_Usage; exit 1; }

test/preextracttest

@@ -0,0 +1,98 @@
+#!/bin/bash
+set -eu
+THIS="$(readlink -f "$0")"
+THISDIR="$(dirname "${THIS}")"
+SUT="$(dirname "${THISDIR}")/makeself.sh"
+
+setUp() {
+  temp=$(mktemp -d -t XXXXX)
+  pushd "${temp}"
+  mkdir src
+  echo "echo This is a test" > src/startup.sh
+  chmod a+x src/startup.sh
+}
+
+tearDown() {
+  popd
+  rm -rf "${temp}"
+}
+
+testPreextractOpts() {
+  echo 'echo A complex pre-extraction script.
+    sleep 99 &
+    cat a.txt 2>/dev/null || cat b.txt && cat c.txt
+    echo "$$ Some\toutput\n\a\b\0777 $var1 ${var2} `cat var3.txt` $(env)" > text.txt
+  ' > preextract.sh
+
+  ${SUT} --nox11 --preextract preextract.sh src src.sh alabel ./startup.sh
+  assertEquals 0 $?
+
+  ./src.sh --show-preextract > show-preextract.out
+  assertEquals 0 $?
+
+  diff preextract.sh show-preextract.out
+  assertEquals 0 $?
+}
+
+testWithNoPreextractOpts() {
+  ${SUT} src src.sh alabel ./startup.sh
+  assertEquals 0 $?
+
+  ./src.sh --show-preextract
+  assertEquals 1 $?
+}
+
+testPreextractRun() {
+  echo 'echo Validating provided options...' > preextract.sh
+  ${SUT} --nox11 --preextract preextract.sh src src.sh alabel ./startup.sh
+  assertEquals 0 $?
+
+  ./src.sh
+  assertEquals 0 $?
+
+  ./src.sh | grep -qF 'Validating provided options...'
+  assertEquals 0 $?
+}
+
+testPreextractNoexec() {
+  echo 'exit 2' > preextract.sh
+  ${SUT} --preextract preextract.sh src src.sh alabel ./startup.sh
+  assertEquals 0 $?
+
+  ./src.sh
+  assertEquals 1 $?
+
+  ./src.sh --noexec
+  assertEquals 0 $?
+}
+
+testPreextractArgs() {
+  echo 'echo $*' > preextract.sh
+  ${SUT} --nox11 --preextract preextract.sh src src.sh alabel ./startup.sh --logdir /var/log
+  assertEquals 0 $?
+
+  test_cmd='./src.sh -- --env dev'
+
+  eval "${test_cmd}"
+  assertEquals 0 $?
+
+  eval "${test_cmd}" | grep -qF -- '--logdir /var/log --env dev'
+  assertEquals 0 $?
+}
+
+testPreextractEnvPassing() {
+  # imitate user input
+  echo 'echo "export INSTALLATION_DIR=/usr/bin" > preextract.env' > preextract.sh
+  echo '. ./preextract.env; echo $INSTALLATION_DIR' > src/startup.sh
+  ${SUT} --nox11 --preextract preextract.sh src src.sh alabel ./startup.sh
+  assertEquals 0 $?
+
+  ./src.sh
+  assertEquals 0 $?
+
+  ./src.sh | grep -qF '/usr/bin'
+  assertEquals 0 $?
+}
+
+# Load and run shUnit2.
+source "./shunit2/shunit2"