I'm a starter at this(make), and having some problems trying to grep for a text in a file (as part of the make process on Windows). The larger problem I'm trying to solve is to check whether all binary executables in a given directory have their respective dependencies satisfied. I use depends.exe (Dependency Walker) for the later part, whose output file I'm trying to grep, and possibly abort the build process if the dependency validation fails.
binary-dependency-validate:
for BINARYEXEC in $(shell $(PATH_TO_FIND_EXE) $(PRE_DEFINED_DIR) -name "*.exe"); do \
$(PATH_TO_DEPENDS_EXE) /c /pb /ot $(PRE_DEFINED_DIR)/$$BINARYEXEC-depends.txt $(PRE_DEFINED_DIR)/$$BINARYEXEC ; \
ifeq ($(shell $(PATH_TO_GREP_EXE) "Error: At least one required implicit or forwarded dependency was not found." $(PRE_DEFINED_DIR)/$$BINARYEXEC-depends.txt),); \
#echo "Dependency ok" ; \
endif ; \
done
I'm encountering the following error :
line 1: syntax error near unexpected token `,'
Any suggestions would greatly help. I looked at this post and tried aligning ifeq without indentation as well (that didn't help either.)
The problem is that you are mixing Make language with shell language.
A makefile contains rules, and a rule contains commands which are executed by a shell:
target:
first command
second command
The commands are in shell language, and each command must be preceded by a TAB.
There are conditionals in Make:
ifeq (foo, bar)
VAR = something
endif
(The indentation is just for the eye.)
There are also conditionals in the various scripting languages:
if [ -f log ]
then
echo "log exists."
fi
A Make conditional can enclose a command within a rule:
target:
ifeq (foo, bar)
first command
endif
second command
Make will evaluate this conditional before running the rule, and there must be no TAB before ifeq or endif, because Make must not interpret them as commands to be passed to the shell.
A command (in a rule) can contain a shell conditional:
target:
if [ -f log ]; \
then echo "log exists." ; \
fi
The indentation before if is a TAB. The other whitespace is for the eye.
Your makefile has a Make conditional in the middle of a shell command; Make can't evaluate the conditional before the command executes, and the shell can't understand Make syntax. You should use a shell conditional.
It seems like you have a stray comma on the ifeq line
binary-dependency-validate:
for BINARYEXEC in $(shell $(PATH_TO_FIND_EXE) $(PRE_DEFINED_DIR) -name "*.exe"); do \
$(PATH_TO_DEPENDS_EXE) /c /pb /ot $(PRE_DEFINED_DIR)/$$BINARYEXEC-depends.txt $(PRE_DEFINED_DIR)/$$BINARYEXEC ; \
ifeq ($(shell $(PATH_TO_GREP_EXE) "Error: At least one required implicit or forwarded dependency was not found." $(PRE_DEFINED_DIR)/$$BINARYEXEC-depends.txt)); \
#echo "Dependency ok" ; \
endif ; \
done
Related
Considering that every command is run in its own shell, what is the best way to run a multi-line bash command in a makefile? For example, like this:
for i in `find`
do
all="$all $i"
done
gcc $all
You can use backslash for line continuation. However note that the shell receives the whole command concatenated into a single line, so you also need to terminate some of the lines with a semicolon:
foo:
for i in `find`; \
do \
all="$$all $$i"; \
done; \
gcc $$all
But if you just want to take the whole list returned by the find invocation and pass it to gcc, you actually don't necessarily need a multiline command:
foo:
gcc `find`
Or, using a more shell-conventional $(command) approach (notice the $ escaping though):
foo:
gcc $$(find)
As indicated in the question, every sub-command is run in its own shell. This makes writing non-trivial shell scripts a little bit messy -- but it is possible! The solution is to consolidate your script into what make will consider a single sub-command (a single line).
Tips for writing shell scripts within makefiles:
Escape the script's use of $ by replacing with $$
Convert the script to work as a single line by inserting ; between commands
If you want to write the script on multiple lines, escape end-of-line with \
Optionally start with set -e to match make's provision to abort on sub-command failure
This is totally optional, but you could bracket the script with () or {} to emphasize the cohesiveness of a multiple line sequence -- that this is not a typical makefile command sequence
Here's an example inspired by the OP:
mytarget:
{ \
set -e ;\
msg="header:" ;\
for i in $$(seq 1 3) ; do msg="$$msg pre_$${i}_post" ; done ;\
msg="$$msg :footer" ;\
echo msg=$$msg ;\
}
The ONESHELL directive allows to write multiple line recipes to be executed in the same shell invocation.
all: foo
SOURCE_FILES = $(shell find . -name '*.c')
.ONESHELL:
foo: ${SOURCE_FILES}
FILES=()
for F in $^; do
FILES+=($${F})
done
gcc "$${FILES[#]}" -o $#
There is a drawback though : special prefix characters (‘#’, ‘-’, and ‘+’) are interpreted differently.
https://www.gnu.org/software/make/manual/html_node/One-Shell.html
Of course, the proper way to write a Makefile is to actually document which targets depend on which sources. In the trivial case, the proposed solution will make foo depend on itself, but of course, make is smart enough to drop a circular dependency. But if you add a temporary file to your directory, it will "magically" become part of the dependency chain. Better to create an explicit list of dependencies once and for all, perhaps via a script.
GNU make knows how to run gcc to produce an executable out of a set of .c and .h files, so maybe all you really need amounts to
foo: $(wildcard *.h) $(wildcard *.c)
What's wrong with just invoking the commands?
foo:
echo line1
echo line2
....
And for your second question, you need to escape the $ by using $$ instead, i.e. bash -c '... echo $$a ...'.
EDIT: Your example could be rewritten to a single line script like this:
gcc $(for i in `find`; do echo $i; done)
I wanted to test some expressions of the ifeq kind that run a shell command that I read somewhere, so I wrote this tiny mymakefile (all lines being indented with a tab):
ifeq ($(shell echo test 2>/dev/null; echo $$?),0)
$(info I am inside)
endif
... and I tried to run it:
$ make -f mymakefile
make: *** No targets. Stop.
How could I test expressions like this inside their own makefile? Do I need to define a default target, or not? And how should the commands be formatted (indented with a tab, or space, or not indented at all?)
Well, I got somewhere - apparently, one must specify a target; but since I'm a make noob, I would love to see a more qualified answer.
I found this link https://www.gnu.org/software/make/manual/html_node/Conditional-Example.html that gave me a hint.. Anyways, this is mymakefile now:
.PHONY: default
default: mytarget;
ifeq ($(shell echo test 2>/dev/null; echo $$?),0)
$(info I am inside)
else
$(info I am outside)
endif
mytarget:
\t (TAB) echo A
So, the mytarget here is just a dummy, which simply does an echo A; running this prints:
$ make -f mymakefile
I am outside
echo A
A
If you don't want the echo A printed, suppress it with at sign: #echo A.
The echo A line has to be indented with a TAB - else error "mymakefile:11: *** missing separator. Stop.".
Strangely, if I indent the two $(info... lines with a TAB, then "I am outside" is printed last (?!), but when they are not indented (or indented with spaces), then it is printed first (as per the order in the file).
As part of my makefile I need to download and build ZLib. However I want to ensure that when I download ZLib, it is correct by comparing the sha256 of the downloaded .tar.gz against the known correct sha256 value. This need to work on multiple platforms.
I have so far something like the following, however the value of ZLIB_SHA256_ACTUAL always seems to be blank when I compare it with ZLIB_SHA256, so my makefile always exits with an error because the checksums are not the same. I am newish to Makefiles, can someone tell me what I am doing wrong please?
ZLIB_VER = 1.2.11
ZLIB_SHA256 = c3e5e9fdd5004dcb542feda5ee4f0ff0744628baf8ed2dd5d66f8ca1197cb1a1
SHA256_CMD = sha256sum
ifeq ($(PLATFORM), OS_MACOSX)
SHA256_CMD = openssl sha256 -r
endif
ifeq ($(PLATFORM), OS_SOLARIS)
SHA256_CMD = digest -a sha256
endif
libz.a:
-rm -rf zlib-$(ZLIB_VER)
curl -O -L http://zlib.net/zlib-$(ZLIB_VER).tar.gz
ZLIB_SHA256_ACTUAL = $(SHA256_CMD) zlib-$(ZLIB_VER).tar.gz
ifneq ($(ZLIB_SHA256), $(ZLIB_SHA256_ACTUAL))
$(error zlib-$(ZLIB_VER).tar.gz checksum mismatch, expected="$(ZLIB_SHA256)" actual="$(ZLIB_SHA256_ACTUAL)")
endif
tar xvzf zlib-$(ZLIB_VER).tar.gz
cd zlib-$(ZLIB_VER) && CFLAGS='-fPIC' ./configure --static && make
cp zlib-$(ZLIB_VER)/libz.a .
A makefile consists of two different programming languages in one file. Most of the file uses makefile syntax, that make understands and parses. But the recipes of the rules use shell syntax, which make doesn't try to interpret: it just passes the contents of the recipe to the shell to interpret.
The recipe is the part of the makefile indented with a TAB character, after a target definition. So in your example above, the target definition is libz.a: and all the lines after that which are indented with a TAB, are recipe lines. They are passed to the shell, not run by make.
The recipe is a single block of lines; you cannot intersperse recipe lines with makefile lines. Once make sees the first non-recipe line, that's the end of the recipe and make starts treating the remaining lines as if they were makefile lines.
Let's look at your rule:
libz.a:
-rm -rf zlib-$(ZLIB_VER)
curl -O -L http://zlib.net/zlib-$(ZLIB_VER).tar.gz
OK, this is fine: you've created a target libz.a and provided two command lines, which are valid shell commands, in your recipe.
ZLIB_SHA256_ACTUAL = $(SHA256_CMD) zlib-$(ZLIB_VER).tar.gz
OK, now you have problems; this is a make variable assignment, not a shell command, but since you've indented it with a TAB make will not interpret it: make will just pass it to the shell. That's not a valid shell command (in the shell, variable assignments cannot have spaces around the equal sign); this is trying to run a program named literally ZLIB_SHA256_ACTUAL and pass it the arguments = and the expansion of the SHA256_CMD variable. Even if this was recognized as a make assignment it wouldn't do what you want since it would just set the value of the variable to the string openssl sha256 -r zlib-1.2.11.tar.gz: you want to run that command and set the variable to the output.
Then the next lines:
ifneq ($(ZLIB_SHA256), $(ZLIB_SHA256_ACTUAL))
$(error zlib-$(ZLIB_VER).tar.gz checksum mismatch, expected="$(ZLIB_SHA256)" actual="$(ZLIB_SHA256_ACTUAL)")
endif
Again, this is wrong because these are make commands but you've put them into a recipe which means they'll be passed to the shell, but the shell doesn't know anything about them.
However, they never get the chance to be passed to the shell because the one thing make does with a recipe before it sends it off to the shell is expand all make variables and functions. So, when make expands this it runs the error function and that immediately fails and make never has a chance to try to run the recipe.
This is the tricky part of make. Maybe I've just confused you with all of the above stuff.
The short, simple answer is: you have to use shell commands to perform operations in a recipe. You cannot use make commands (like ifeq etc.), and if you want to set variables in a recipe they have to be shell variables, not make variables.
So, you want something like this, which uses shell syntax not make syntax for the variable assignment and test.
EDIT Note your SHA generation command doesn't print just the SHA it also prints the name of the file, so you can't compare them as strings: they'll never be the same. You need to do something fancier; there are many ways to go about it. Here I decided to use case to do the comparison:
libz.a:
-rm -rf zlib-$(ZLIB_VER)
curl -O -L http://zlib.net/zlib-$(ZLIB_VER).tar.gz
ZLIB_SHA256_ACTUAL=`$(SHA256_CMD) zlib-$(ZLIB_VER).tar.gz`; \
case "$$ZLIB_SHA256_ACTUAL " in \
($(ZLIB_SHA256)\ *) : ok ;; \
(*) echo zlib-$(ZLIB_VER).tar.gz checksum mismatch, expected=\"$(ZLIB_SHA256)\" actual=\"$$ZLIB_SHA256_ACTUAL\"; \
exit 1 ;; \
esac
tar xvzf zlib-$(ZLIB_VER).tar.gz
cd zlib-$(ZLIB_VER) && CFLAGS='-fPIC' ./configure --static && $(MAKE)
cp zlib-$(ZLIB_VER)/libz.a .
Note that each logical line in the recipe is passed to a new instance of the shell, so if you want to set a shell variable and test its value you have to combine physical lines into one logical line with the backslash/newline syntax.
Also, when running a sub-make in a recipe you should always use the variable $(MAKE) and never use just make.
I'm using a Makefile to compile my project. I get to a point which is:
$(MAKE) <some flags>; \
$(UPLOAD_SCRIPT)
The $(MAKE) line actually compiles the code, but I only want the upload script to run if the make was successful (i.e. no errors). Is there a way to do this? I'm imagining something with exit codes, storing the result in a variable, and an if statement, but I'm not super familiar with Makefiles.
Chain the 2 commands using && like this instead:
mytarget:
$(MAKE) <some flags> && $(UPLOAD_SCRIPT)
If you have more lines, and do not want to make your line look very long using &&, you can use set -e, so that the shell stops on the first error.
-e When this option is on, if a simple command fails for any of the
reasons listed in Consequences of Shell Errors or returns an exit
status value >0, and is not part of the compound list following a
while, until, or if keyword, and is not a part of an AND or OR list,
and is not a pipeline preceded by the ! reserved word, then the shell
shall immediately exit.
mytarget:
set -e; \
cmd1; \
cmd2
Considering that every command is run in its own shell, what is the best way to run a multi-line bash command in a makefile? For example, like this:
for i in `find`
do
all="$all $i"
done
gcc $all
You can use backslash for line continuation. However note that the shell receives the whole command concatenated into a single line, so you also need to terminate some of the lines with a semicolon:
foo:
for i in `find`; \
do \
all="$$all $$i"; \
done; \
gcc $$all
But if you just want to take the whole list returned by the find invocation and pass it to gcc, you actually don't necessarily need a multiline command:
foo:
gcc `find`
Or, using a more shell-conventional $(command) approach (notice the $ escaping though):
foo:
gcc $$(find)
As indicated in the question, every sub-command is run in its own shell. This makes writing non-trivial shell scripts a little bit messy -- but it is possible! The solution is to consolidate your script into what make will consider a single sub-command (a single line).
Tips for writing shell scripts within makefiles:
Escape the script's use of $ by replacing with $$
Convert the script to work as a single line by inserting ; between commands
If you want to write the script on multiple lines, escape end-of-line with \
Optionally start with set -e to match make's provision to abort on sub-command failure
This is totally optional, but you could bracket the script with () or {} to emphasize the cohesiveness of a multiple line sequence -- that this is not a typical makefile command sequence
Here's an example inspired by the OP:
mytarget:
{ \
set -e ;\
msg="header:" ;\
for i in $$(seq 1 3) ; do msg="$$msg pre_$${i}_post" ; done ;\
msg="$$msg :footer" ;\
echo msg=$$msg ;\
}
The ONESHELL directive allows to write multiple line recipes to be executed in the same shell invocation.
all: foo
SOURCE_FILES = $(shell find . -name '*.c')
.ONESHELL:
foo: ${SOURCE_FILES}
FILES=()
for F in $^; do
FILES+=($${F})
done
gcc "$${FILES[#]}" -o $#
There is a drawback though : special prefix characters (‘#’, ‘-’, and ‘+’) are interpreted differently.
https://www.gnu.org/software/make/manual/html_node/One-Shell.html
Of course, the proper way to write a Makefile is to actually document which targets depend on which sources. In the trivial case, the proposed solution will make foo depend on itself, but of course, make is smart enough to drop a circular dependency. But if you add a temporary file to your directory, it will "magically" become part of the dependency chain. Better to create an explicit list of dependencies once and for all, perhaps via a script.
GNU make knows how to run gcc to produce an executable out of a set of .c and .h files, so maybe all you really need amounts to
foo: $(wildcard *.h) $(wildcard *.c)
What's wrong with just invoking the commands?
foo:
echo line1
echo line2
....
And for your second question, you need to escape the $ by using $$ instead, i.e. bash -c '... echo $$a ...'.
EDIT: Your example could be rewritten to a single line script like this:
gcc $(for i in `find`; do echo $i; done)