Generate multiline file with Make - bash

Question

I want to create a multiline file with Make, having exact content:
#!/bin/bash
if [ "$JAVA_HOME" = "" ]; then echo "Please set JAVA_HOME"; exit 1; fi
export CONFIG_VARS=$( cat <<EOF
-Dmapred.job.tracker=$JT
EOF
)
${HADOOP_HOME}/bin/hadoop $1 $HADOOP_CONFIG_VARS ${*:2} 2>&1 | grep -v SLF4J
How can I tell make to output a file with this exact content somewhere?
I tried this:
define SCRIPT_CONTENT
#!/bin/bash
if [ "$JAVA_HOME" = "" ]; then echo "Please set JAVA_HOME"; exit 1; fi
export CONFIG_VARS=$( cat <<EOF
-Dmapred.job.tracker=$JT
EOF
)
${HADOOP_HOME}/bin/hadoop $1 $HADOOP_CONFIG_VARS ${*:2} 2>&1 | grep -v SLF4J
endef
export SCRIPT_CONTENT
bin/script:
#echo "$$SCRIPT_CONTENT" > bin/script
This paricular solution 1) wipes $ and first char after $-es and 2) is ugly because the definition should happen outside of the particular target where it's needed :(
I also tried this:
bin/script:
#echo '
#!/bin/bash
if [ "$JAVA_HOME" = "" ]; then echo "Please set JAVA_HOME"; exit 1; fi
export CONFIG_VARS=$( cat <<EOF
-Dmapred.job.tracker=$JT
EOF
)
${HADOOP_HOME}/bin/hadoop $1 $HADOOP_CONFIG_VARS ${*:2} 2>&1 | grep -v SLF4J
' > bin/script
This returns error when in make, works outside of make...
Any suggestion is very welcome!

Answer 1

Make wants any $ characters that should be reproduced literally to be escaped by inserting another $ in front of them.
More broadly, though, it seems like you're trying to use Make as a shell-script replacement. The more idomatic way to do this would be to put that content in a source file that you can copy to the destination, or to put it in a script that will write it into a specified destination. The Makefile then just has to invoke the copy command or the script.

Answer 2

With the help from this magnificent answer, I cooked up the following.
# From https://stackoverflow.com/a/8316519/874188
define \n
endef
define SCRIPT_CONTENT
#!/bin/bash
if [ "$$JAVA_HOME" = "" ]; then echo "Please set JAVA_HOME"; exit 1; fi
export CONFIG_VARS=$$( cat <<EOF
-Dmapred.job.tracker=$$JT
EOF
)
$${HADOOP_HOME}/bin/hadoop $$1 $$HADOOP_CONFIG_VARS $${*:2} 2>&1 | grep -v SLF4J
endef
bin/script:
echo '$(subst $(\n),\n,$(SCRIPT_CONTENT))' >$#
When testing, I found that I needed to have a semicolon at the end of the echo line when it didn't have any redirection. I can speculate that there is a built-in echo which gets invoked when there are no shell metacharacters in the command line?
Also, notice that the definition cannot contain any single quotes, and that all dollar signs have to be doubled. Maybe one or the other of these restrictions could be removed; I was unsuccessful, but then I didn't spend too much time or effort.

Answer 3

You cannot do this in make. Beyond what Novelocrat says regarding $, there's the fact that make is line-oriented and does not have any ability to generate a command that contains a newline character. All newlines that appear unescaped (without a backslash before them) are parsed by make as ending that recipe line, and each recipe line is sent to a different invocation of the shell. If you want the entire command to be sent as a single string to the same shell, then you must escape the newlines.
However, make will remove all backslash/newline pairs before it runs the command.
The only possible way to do this completely within make is to generate the file one line at a time, like this:
bin/script:
#echo '#!/bin/bash' > $#
#echo 'if [ "$$JAVA_HOME" = "" ]; then echo "Please set JAVA_HOME"; exit 1; fi' >> $#
#echo 'export CONFIG_VARS=$$( cat <<EOF' >> $#
#echo ' -Dmapred.job.tracker=$$JT' >> $#
#echo 'EOF' >> $#
#echo ')' >> $#
#echo '$${HADOOP_HOME}/bin/hadoop $$1 $$HADOOP_CONFIG_VARS $${*:2} 2>&1 | grep -v SLF4J' >> $#
As Novelocrat says, the typical way this is done is to have the script file as a separate file and copy it where you want it, rather than generating it.