Makefile ifeq problem - path

I am trying to use ifeq in my rule pattern and I have problems with it. This is the rule I am having trouble with:
$(OBJS): $(OBJDIR)/%.o : ../%.c
#mkdir -p $(dir $#)
ifeq(mcc.exe,$(CC))
o_file:=$(shell echo $# | sed -e 's/\/cygdrive\///' | sed -e 's/\([a-zA-Z]\)/\1:/')
$(CC) $(CFLAGS) $< -o $(o_file)
else
$(CC) $(CFLAGS) $< -o $#
endif
When I run this, I get:
"/bin/sh: -c: line 0: syntax error near unexpected token `mcc.exe,mcc.exe'
/bin/sh: -c: line 0: `ifeq(mcc.exe,mcc.exe)'"
But, when I don't use indention, then I get : "Makefile:77: * missing separator. Stop."
I am using GNU make 3.81 on Cygwin. Whole issue with the ifeq comes from the fact that I have same Makefile for two toolchains and one of them (mcc.exe) can not cope with the /cygdrive/c/.../something paths, but instead there should be c:/.../something path. If you know any other way to work around this, I would be also very grateful!
Thank you in advance!

The lines containing ifeq..., else, and endif should not start with a tab. If they do they are treated as part of the recipe and sent to the shell; this leads to the syntax error you get from /bin/sh; see the make manual for an example.
I'm not exactly sure why you get an error when you don't use indentation. Perhaps you can't define a variable in a recipe like this?
Edit: I see you've found the answer. So, no indentation, and a space between ifeq and the parenthesis.

Related

Make offsetting file contents during build

I'm trying to use Make to ... make modular Dockerfiles. Long story short, I want to centralize certain elements and make the composable and reusable, like classes and functions really, but the Dockerfile syntax does not - and according to the developers, will not - offer any facilities in the image of C's #include or similar composability solutions. Not to worry, #include and friends to the rescue!
Except...
I have the following Makefile in my project:
BUILD_DIR := ${CI_PROJECT_DIR}/build
TEMPLATE_FILES := $(shell find ${CI_PROJECT_DIR} -name '*.build')
TEMPLATE_FILENAMES := $(foreach file,$(TEMPLATE_FILES),$(BUILD_DIR)/$(notdir $(file)).built)
BUILT_TEMPLATES := $(TEMPLATE_FILENAMES:.build.built=.built)
DOCKER_FILES := $(shell find ${CI_PROJECT_DIR} -name '*.Dockerfile')
DOCKER_OBJS := $(foreach file,$(DOCKER_FILES),$(BUILD_DIR)/$(notdir $(file)))
all: $(BUILT_TEMPLATES) $(DOCKER_OBJS)
$(BUILD_DIR)/%.built: $(TEMPLATE_FILES) $(BUILD_DIR) # build any templated Dockerfiles
cpp -E -P -o $(BUILD_DIR)/$(notdir $#) -I ${CI_PROJECT_DIR}/modules $<
sed -i 's/__NL__ /\n/g' $(BUILD_DIR)/$(notdir $#)
$(BUILD_DIR)/%.Dockerfile: $(DOCKER_FILES) $(BUILD_DIR)
cp $< $(BUILD_DIR)/$(notdir $(#))
$(BUILD_DIR):
mkdir -p $(BUILD_DIR)
.PHONY: clean
clean:
-rm -r $(BUILD_DIR)
The objective is to run the templated Dockerfiles through GCC to compile the #includes in them into proper Docker instructions, and just copy the rest of the files. Sounds simple enough.
Except that it looks like all the target files are "offset" from their sources - like the file names are correct, but the contents are from a file elsewhere in the list, and with no discernible order either.
One thing that I'm fairly sure is wrong - but even more wrong otherwise - is the line
$(BUILD_DIR)/%.built: $(TEMPLATE_FILES) $(BUILD_DIR) # build any templated Dockerfiles
By all manuals and documentation, it ought to be
$(BUILD_DIR)/%.built: %.build $(BUILD_DIR) # build any templated Dockerfiles
but that's even worse, because then Make just says make: *** No rule to make target '/docker/build/runner-dart-2-18-firebase.built', needed by 'all'. Stop.
I'm out of ideas here, along with my limited knowledge of Make. What am I missing to make Make make - sorry - my Dockerfiles?
This line:
$(BUILD_DIR)/%.built: $(TEMPLATE_FILES) $(BUILD_DIR)
Says that if make wants to build a target that matches that pattern, and it can find all the prerequisites, then the pattern rule matches and the recipe can be used. Let's ignore BUILD_DIR (note that it's always a bad idea to list a directory as a prerequisite, but that's not causing this problem). Suppose TEMPLATE_FILES is set to the value ./foo/foo.build ./bar/bar.build. Now the above rule expands to:
./build/%.built: ./foo/foo.build ./foo/bar.build ./build
What is the recipe?
cpp -E -P -o $(BUILD_DIR)/$(notdir $#) -I ${CI_PROJECT_DIR}/modules $<
First it's always wrong to create a file that is not exactly $# so you should use just $# not $(BUILD_DIR)/$(notdir $#). But more importantly, what will $< be set to? It is always set to the first prerequisite, and the first prerequisite is always ./foo/foo.build. So every time you run this recipe, regardless of which .built file you're trying to create, you will always be preprocessing the first .build file.
Your idea that you want this instead:
$(BUILD_DIR)/%.built: %.build $(BUILD_DIR)
is correct, in general. Why do you get the error? Because if you are trying to build the target ./build/foo.built, then the stem (part that matches %) is foo. Then make will look to see if the prerequisite foo.build exists or can be created, because you said the prerequisite is %.build. That file does NOT exist and CANNOT be created (make doesn't know how to create it), because the file is ./foo/foo.build not foo.build which is a totally different file.
You have three options. You can either write separate rules for each source directory:
$(BUILD_DIR)/%.built: foo/%.build
...
$(BUILD_DIR)/%.built: bar/%.build
...
Or, you can change your generated files so they are not all in the same directory but instead keep the source directory structure; you would change this:
TEMPLATE_FILENAMES := $(foreach file,$(TEMPLATE_FILES),$(BUILD_DIR)/$(notdir $(file)).built)
BUILT_TEMPLATES := $(TEMPLATE_FILENAMES:.build.built=.built)
to just this:
BUILT_TEMPLATES := $(patsubst %.build,$(BUILD_DIR)/%.built,$(TEMPLATE_FILES))
then create the output directory as part of the recipe:
#mkdir -p $(#D)
cpp -E -P -o $# -I ${CI_PROJECT_DIR}/modules $<
sed -i 's/__NL__ /\n/g' $#
Or finally, you could use VPATH to tell make what directories to look in to find the *.build files:
VPATH := $(sort $(dir $(TEMPLATE_FILES)))
(note, you should choose only one of these options).

Error handling in Makefile

What is wrong with this Makefile?
I want to compile some lua files to check if there are any unexpected globals defined. I'm doing this by grepping the output of luac -l and then ignoring known globals.
So for a given lua file everything is OK if grep doesn't find anything, having ignored known lua globals.
As grep's return status code is 0 if it does find something and 1 if it doesn't I want to force an error if the status code from the grep is 0 and allow everything to continue if it isn't.
The Makefile is like this
IGNORE_GLOBALS = "dofile\|string\|tostring\|tonumber\|math\|io\|type\|os\|table\|pairs\|next\|require"
all: $(patsubst src/common/%.lua, %.lua, $(wildcard src/common/*.lua))
%.lua:
#echo check $#
#luac -l src/common/$# | grep '.ETGLOBAL' | grep -v $(IGNORE_GLOBALS) && $(error Unexpected globals in $#) || echo "No unexpected globals in $#"
But when I run it immediately quits on the first file, which happens to have no unexpected globals with
Makefile:10: *** Unexpected globals in chat-cmd.lua. Stop.
line 10 is surprisingly the line before, i.e.
#echo check $#
Interestingly if I replace $(error ...) with echo ..., as in
#luac -l src/common/$# | grep '.ETGLOBAL' | grep -v $(IGNORE_GLOBALS) && echo "Unexpected globals in $#" || echo "No unexpected globals in $#"
it behaves as intended.
As #siffiejoe says in the comment. $(error) is make function and is run when the recipe as a whole is being evaluated (you can think of it like hoisting if that helps).
So as soon as the recipe needs to be run (and the first line executed) the $(error) call is evaluated.
Note: In the shell X && Y || Z is not a ternary operation. Z will be run if X succeeds and Y fails as well as when X fails. This doesn't matter here as echo cannot really fail but in general is worth paying attention to.
You want to use something more like #! lua ... | grep -v $(IGNORE_GLOBALS) || { echo 'Unexpected globals in $#'; exit 1; } there. This doesn't spit out the "everything's ok" message but removes the X && Y || Z ternary issue.
If you wanted to keep that message the simplest thing to do would be to move to an actual if statement.

clang: Remove comments in preprocessed files?

is there a way to tell clang to remove comment lines when generating preprocessed output?
Apparently, this is a difference between gcc and clang, and I have not found an option to do so
Thanks
Alex
To be more precise: It seems that I have an issue with input from file, please see this sample:
CONTENT="// \$REMOVE BEFORE FLIGHT\$\r\nprintf(\"HelloWorld!\");"
echo "Original:\n$CONTENT"
echo "-------------------------"
echo "From stdin"
echo $CONTENT | cpp -P -E -nostdinc -xc++ -
echo "-------------------------"
echo "From file"
echo $CONTENT > foo.sample
cpp -P -E -nostdinc -xc++ foo.sample
echo "\n What gives?"
Addition: It appears, that the -x Argument is changed. Using -v, I can see that on the command line, actually -x c++ is passed, whereas when using a file as input, it is changed to -x c.
Any idea why?

Best way to search the path in shell

I've got a small script called "onewhich". Its purpose is to behave like which, except that it will only give the FIRST occurrence of any executables specified as options, as found in the order they'd appear in the path.
So for example, if my path is /opt/bin:/usr/bin:/bin, and I have both /opt/bin/runme and /usr/bin/runme, then the command onewhich runme would return /opt/bin/runme.
But if I also have a /usr/bin/doit, then the command onewhich doit runme would return /usr/bin/doit instead.
The idea is to walk through the path, check for each executable specified, and if it exists, show it and exit.
Here's the script so far.
#!/bin/sh
for what in "$#"; do
for loc in `echo "${PATH}" | awk -vRS=: 1`; do
if [ -f "${loc}/${what}" ]; then
echo "${loc}/${what}"
exit 0
fi
done
done
exit 1
The problem is, I want to be better about PATH directories with special characters. Every second shell question here on StackOverflow talks about how bad it is to parse paths with tools like awk and sed. There's even a bash faq entry about it. (Proviso: I'm not using bash for this, but the recommendation is still valid.)
So I tried rewriting the script to separate paths in a pipe, like this"
#!/bin/sh
for what in "$#"; do
echo "${PATH}" | awk -vRS=: 1 | while read loc ; do
if [ -f "${loc}/${what}" ]; then
echo "${loc}/${what}"
exit 0
fi
done
done
exit 1
I'm not sure if this gives me any real advantage (since $loc is still inside quotes), but it also doesn't work because for some reason, the exit 0 seems to be ignored. Or ... it exits something (the sub-shell with the while loop that terminates the pipe, maybe), but the script exits with a value of 1 every time.
What's a better way to step through directories in ${PATH} without the risk that special characters will confuse things?
Alternately, am I reinventing the wheel? Is there maybe a way to do this that's built in to existing shell tools?
This needs to run in both Linux and FreeBSD, which is why I'm writing it in Bourne instead of bash.
Thanks.
This doesn't directly answer your question, but does eliminate the need to parse PATH at all:
onewhich () {
for what in "$#"; do
which "$what" 2>/dev/null && break
done
}
This just calls which on each command on the input list until it finds a match.
To parse PATH, you can simply set `IFS=':'.
if [ "${IFS:-x}" = "${IFS-x}" ]; then
# Only preserve the value of IFS if it is currently set
OLDIFS=$IFS
fi
IFS=":"
for f in $PATH; do # Do not quote $PATH, to allow word splitting
echo $f
done
if [ "${OLDIFS:-x}" = "${OLDIFS-x}" ]; then
IFS=$OLDIFS
fi
The above will fail if any of the directories in PATH actually contain colons.
Your first method looks to me as if it should work. In practical terms, if it's really the $PATH you'll be searching, it's unlikely you'll have spaces and newlines embedded in directories there. If you do, it's probably time to refactor.
But still, I don't think you're at risk from the possibility of bad names clobbering your loop, since you're wrapping variables in quotes. At worst, I suspect you might miss the odd valid executable, but I can't see how the script would generate errors. (I don't see how the script would miss valid executables, and I haven't tested - I'm just saying I don't see problems at first glance.)
As for your second question, about the loop, I think you've hit the nail on the head. When you run a pipe like this | that | while condition; do things; done, the while loop runs in its own shell at the end of the pipe. Exiting that shell may terminate the actions of the pipe, but that only brings you back to the parent shell, which has its own thread of execution that terminates with exit 1.
As for a better way to do this, I would consider which.
#!/bin/sh
for what in "$#"; do
which "$what"
done | head -1
And if you really want the exit values as well:
#!/bin/sh
for what in "$#"; do
which "$what" && exit 0
done
exit 1
The second might even be fewer resources, as it doesn't have to open a file handle and pipe through head.
You can also split your path using IFS. For example, if you wanted to wrap your loops the other way around, you could do this:
#!/bin/sh
IFS=":"
for loc in $PATH; do
for what in "$#"; do
if [ -x "$loc"/"$what" ]; then
echo "$loc"/"$what"
exit 0
fi
done
done
exit 1
Note that under normal circumstances, you might want to save the old value of $IFS, but you seem to be doing things in a stand-alone script, so the "new" value gets thrown out when the script exits.
All the above code is untested. YMMV.
Another way to get around the need to parse PATH at all is to run the builtin type command in new shell with a stripped environment (i. e. there simply are no functions or aliases to look up; cf. env -i sh -c 'type cmd 2>/dev/null).
# using `cmd` instead of $(cmd) for portability
onewhich() {
ec=0 # exit code
for cmd in "$#"; do
command -p env -i PATH="$PATH" sh -c '
export LC_ALL=C LANG=C
cmd="$1"
path="`type "$cmd" 2>/dev/null`"
if [ X"$path" = "X" ]; then
printf "%s\n" "error: command \"${cmd}\" not found in PATH" 1>&2
exit 1
else
case "$path" in
*\ /*)
path="/${path#*/}"
printf "%s\n" "$path";;
*)
printf "%s\n" "error: no disk file: $path" 1>&2
exit 1;;
esac
exit 0
fi
' _ "$cmd"
[ $? != 0 ] && ec=1
done
[ $ec != 0 ] && return 1
}
onewhich awk ls sed
onewhich builtin
onewhich if
Since which on success returns two full command paths if two commands are specified as arguments, exit 0 in the first onewhich script above aborts the program prematurely. In addition, if two commands are specified as arguments to which, the exit code of which is set to 1 even if only one command lookup failed (cf. which awk sedxyz ls; echo $?). To mimic this behaviour of the which command it is necessary to toggle on/off two variables (cnt and nomatches below).
onewhich() (
IFS=":"
nomatches=0
for cmd in "$#"; do
cnt=0
for loc in $PATH ; do
if [ $cnt = 0 ] && [ -x "$loc"/"$cmd" ]; then
echo "$loc"/"$cmd"
cnt=1
fi
done
[ $cnt = 0 ] && nomatches=1
done
[ $nomatches = 1 ] && exit 1 || exit 0 # exit 1: at least one cmd was not in PATH
)
onewhich awk ls sed
onewhich awk lsxyz sed
onewhich builtin
onewhich if

grep show all lines, not just matches, set exit status

I'm piping some output of a command to egrep, which I'm using to make sure a particular failure string doesn't appear in.
The command itself, unfortunately, won't return a proper non-zero exit status on failure, that's why I'm doing this.
command | egrep -i -v "badpattern"
This works as far as giving me the exit code I want (1 if badpattern appears in the output, 0 otherwise), BUT, it'll only output lines that don't match the pattern (as the -v switch was designed to do). For my needs, those lines are the most interesting lines.
Is there a way to have grep just blindly pass through all lines it gets as input, and just give me the exit code as appropriate?
If not, I was thinking I could just use perl -ne "print; exit 1 if /badpattern/". I use -n rather than -p because -p won't print the offending line (since it prints after running the one-liner). So, I use -n and call print myself, which at least gives me the first offending line, but then output (and execution) stops there, so I'd have to do something like
perl -e '$code = 0; while (<>) { print; $code = 1 if /badpattern/; } exit $code'
which does the whole deal, but is a bit much, is there a simple command line switch for grep that will just do what I'm looking for?
Actually, your perl idea is not bad. Try:
perl -pe 'END { exit $status } $status=1 if /badpattern/;'
I bet this is at least as fast as the other options being suggested.
$ tee /dev/tty < ~/.bashrc | grep -q spam && echo spam || echo no spam
How about doing a redirect to /dev/null, hence removing all lines, but you still get the exit code?
$ grep spam .bashrc > /dev/null
$ echo $?
1
$ grep alias .bashrc > /dev/null
$ echo $?
0
Or you can simply use the -q switch
-q, --quiet, --silent
Quiet; do not write anything to standard output. Exit
immediately with zero status if any match is found, even if an
error was detected. Also see the -s or --no-messages option.
(-q is specified by POSIX.)

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