| Message ID | 20220128220131.10956-1-brenda.streiff@ni.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | kconfig: let 'shell' return enough output for deep path names | expand |
On Sat, Jan 29, 2022 at 7:02 AM Brenda Streiff <brenda.streiff@ni.com> wrote: > > The 'shell' built-in only returns the first 256 bytes of the command's > output. In some cases, 'shell' is used to return a path; by bumping up > the buffer size to 4096 this lets us capture up to PATH_MAX. > > The specific case where I ran into this was due to commit 1e860048c53e > ("gcc-plugins: simplify GCC plugin-dev capability test"). After this > change, we now use `$(shell,$(CC) -print-file-name=plugin)` to return > a path; if the gcc path is particularly long, then the path ends up > truncated at the 256 byte mark, which makes the HAVE_GCC_PLUGINS > depends test always fail. > > Signed-off-by: Brenda Streiff <brenda.streiff@ni.com> Thanks, applied to linux-kbuild, (but I dropped the change to tests) > --- > scripts/kconfig/preprocess.c | 2 +- > scripts/kconfig/tests/preprocess/builtin_func/Kconfig | 3 +++ > scripts/kconfig/tests/preprocess/builtin_func/expected_stdout | 1 + > 3 files changed, 5 insertions(+), 1 deletion(-) > > diff --git a/scripts/kconfig/preprocess.c b/scripts/kconfig/preprocess.c > index 0590f86df6e4..748da578b418 100644 > --- a/scripts/kconfig/preprocess.c > +++ b/scripts/kconfig/preprocess.c > @@ -141,7 +141,7 @@ static char *do_lineno(int argc, char *argv[]) > static char *do_shell(int argc, char *argv[]) > { > FILE *p; > - char buf[256]; > + char buf[4096]; > char *cmd; > size_t nread; > int i; > diff --git a/scripts/kconfig/tests/preprocess/builtin_func/Kconfig b/scripts/kconfig/tests/preprocess/builtin_func/Kconfig > index baa328827911..e9791a97f731 100644 > --- a/scripts/kconfig/tests/preprocess/builtin_func/Kconfig > +++ b/scripts/kconfig/tests/preprocess/builtin_func/Kconfig > @@ -25,3 +25,6 @@ $(warning,$(shell,printf 'hello\nworld\n\n4\n\n\n')) > # 'lineno' to the line number. > $(warning,filename=$(filename)) > $(warning,lineno=$(lineno)) > + > +# 'shell' can return more than 256 bytes of output > +$(info,$(shell,printf 'hello%01024dworld\n' '0')) > diff --git a/scripts/kconfig/tests/preprocess/builtin_func/expected_stdout b/scripts/kconfig/tests/preprocess/builtin_func/expected_stdout > index 82de3a7e97de..8e03e4dfe8f6 100644 > --- a/scripts/kconfig/tests/preprocess/builtin_func/expected_stdout > +++ b/scripts/kconfig/tests/preprocess/builtin_func/expected_stdout > @@ -1 +1,2 @@ > hello world 0 > +hello0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000world > -- > 2.20.1 >
diff --git a/scripts/kconfig/preprocess.c b/scripts/kconfig/preprocess.c index 0590f86df6e4..748da578b418 100644 --- a/scripts/kconfig/preprocess.c +++ b/scripts/kconfig/preprocess.c @@ -141,7 +141,7 @@ static char *do_lineno(int argc, char *argv[]) static char *do_shell(int argc, char *argv[]) { FILE *p; - char buf[256]; + char buf[4096]; char *cmd; size_t nread; int i; diff --git a/scripts/kconfig/tests/preprocess/builtin_func/Kconfig b/scripts/kconfig/tests/preprocess/builtin_func/Kconfig index baa328827911..e9791a97f731 100644 --- a/scripts/kconfig/tests/preprocess/builtin_func/Kconfig +++ b/scripts/kconfig/tests/preprocess/builtin_func/Kconfig @@ -25,3 +25,6 @@ $(warning,$(shell,printf 'hello\nworld\n\n4\n\n\n')) # 'lineno' to the line number. $(warning,filename=$(filename)) $(warning,lineno=$(lineno)) + +# 'shell' can return more than 256 bytes of output +$(info,$(shell,printf 'hello%01024dworld\n' '0')) diff --git a/scripts/kconfig/tests/preprocess/builtin_func/expected_stdout b/scripts/kconfig/tests/preprocess/builtin_func/expected_stdout index 82de3a7e97de..8e03e4dfe8f6 100644 --- a/scripts/kconfig/tests/preprocess/builtin_func/expected_stdout +++ b/scripts/kconfig/tests/preprocess/builtin_func/expected_stdout @@ -1 +1,2 @@ hello world 0 +hello0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000world
The 'shell' built-in only returns the first 256 bytes of the command's output. In some cases, 'shell' is used to return a path; by bumping up the buffer size to 4096 this lets us capture up to PATH_MAX. The specific case where I ran into this was due to commit 1e860048c53e ("gcc-plugins: simplify GCC plugin-dev capability test"). After this change, we now use `$(shell,$(CC) -print-file-name=plugin)` to return a path; if the gcc path is particularly long, then the path ends up truncated at the 256 byte mark, which makes the HAVE_GCC_PLUGINS depends test always fail. Signed-off-by: Brenda Streiff <brenda.streiff@ni.com> --- scripts/kconfig/preprocess.c | 2 +- scripts/kconfig/tests/preprocess/builtin_func/Kconfig | 3 +++ scripts/kconfig/tests/preprocess/builtin_func/expected_stdout | 1 + 3 files changed, 5 insertions(+), 1 deletion(-)