| Message ID | 20230525002045.82937-1-deborah.brouwer@collabora.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | v4l2-tracer: Fix libv4l2tracer.so loader | expand |
Thanks Deborah, Le mercredi 24 mai 2023 à 17:20 -0700, Deborah Brouwer a écrit : > From: Nicolas Dufresne <nicolas.dufresne@collabora.com> > > The code was still assuming libtools being use, so it didn't work > installed anymore. Also, it didn't work installed if the full > v4l2-tracer path was being passed. > > Fix this by always trying next by libv4l2tracer.so loading (using stat() > to validate) and always fallback to the installed path otherwise. > > Signed-off-by: Nicolas Dufresne <nicolas.dufresne@collabora.com> Mind adding you Singed-off-by ? > --- > Hi - thanks to Nicolas for this patch. > I tested tracing and retracing on both installed and uninstalled > v4l2-tracer including with and without an absolute path and it > all works as expected. > > Note that I've got three sets of v4l2-tracer patches outstanding now, > but they all still apply independently of each other: > > Tuner patches: > https://lore.kernel.org/linux-media/cover.1684453027.git.deborah.brouwer@collabora.com/ > > Debug patches: > https://lore.kernel.org/linux-media/cover.1681245372.git.deborah.brouwer@collabora.com/ > > Thanks, > Deb > > utils/v4l2-tracer/v4l2-tracer.cpp | 33 +++++++++++++++++-------------- > 1 file changed, 18 insertions(+), 15 deletions(-) > > diff --git a/utils/v4l2-tracer/v4l2-tracer.cpp b/utils/v4l2-tracer/v4l2-tracer.cpp > index e3f002a9..7c3662be 100644 > --- a/utils/v4l2-tracer/v4l2-tracer.cpp > +++ b/utils/v4l2-tracer/v4l2-tracer.cpp > @@ -5,6 +5,7 @@ > > #include "retrace.h" > #include <climits> > +#include <sys/stat.h> > #include <sys/wait.h> > #include <time.h> > > @@ -295,24 +296,26 @@ int tracer(int argc, char *argv[], bool retrace) > fclose(trace_file); > > /* > - * Preload the libv4l2tracer library. If the program is installed, load the library > - * from its installed location, otherwise load it locally. If it's loaded locally, > - * use ./configure --disable-dyn-libv4l. > + * Preload the libv4l2tracer library. The libv4l2tracer is looked up next to > + * the executable first in order to support uninstalled build. > */ > std::string libv4l2tracer_path; > std::string program = argv[0]; > - std::size_t idx = program.rfind("/v4l2-tracer"); > - if (idx != std::string::npos) { > - libv4l2tracer_path = program.replace(program.begin() + idx + 1, program.end(), ".libs"); > - DIR *directory_pointer = opendir(libv4l2tracer_path.c_str()); > - if (directory_pointer == nullptr) > - libv4l2tracer_path = program.replace(program.begin() + idx, program.end(), "./.libs"); > - else > - closedir(directory_pointer); > - } else { > - libv4l2tracer_path = LIBTRACER_PATH; > - } > - libv4l2tracer_path += "/libv4l2tracer.so"; > + std::size_t idx = program.rfind("/"); > + struct stat sb; > + > + if (idx == std::string::npos) > + idx = 0; > + else > + idx++; > + > + /* look for libv4l2tracer next to the executable */ > + libv4l2tracer_path = program.replace(program.begin() + idx, program.end(), "libv4l2tracer.so"); > + > + /* otherwise, use the installation path */ > + if (stat(libv4l2tracer_path.c_str(), &sb) == -1) > + libv4l2tracer_path = std::string(LIBTRACER_PATH) + "/libv4l2tracer.so"; > + > if (is_verbose()) > fprintf(stderr, "Loading libv4l2tracer: %s\n", libv4l2tracer_path.c_str()); > setenv("LD_PRELOAD", libv4l2tracer_path.c_str(), 0);
On Thu, May 25, 2023 at 12:45:28PM -0400, Nicolas Dufresne wrote: > Thanks Deborah, > > Le mercredi 24 mai 2023 à 17:20 -0700, Deborah Brouwer a écrit : > > From: Nicolas Dufresne <nicolas.dufresne@collabora.com> > > > > The code was still assuming libtools being use, so it didn't work > > installed anymore. Also, it didn't work installed if the full > > v4l2-tracer path was being passed. > > > > Fix this by always trying next by libv4l2tracer.so loading (using stat() > > to validate) and always fallback to the installed path otherwise. > > > > Signed-off-by: Nicolas Dufresne <nicolas.dufresne@collabora.com> > > Mind adding you Singed-off-by ? Actually Hans already applied your patch (thanks!) but will do it next time. > > > --- > > Hi - thanks to Nicolas for this patch. > > I tested tracing and retracing on both installed and uninstalled > > v4l2-tracer including with and without an absolute path and it > > all works as expected. > > > > Note that I've got three sets of v4l2-tracer patches outstanding now, > > but they all still apply independently of each other: > > > > Tuner patches: > > https://lore.kernel.org/linux-media/cover.1684453027.git.deborah.brouwer@collabora.com/ > > > > Debug patches: > > https://lore.kernel.org/linux-media/cover.1681245372.git.deborah.brouwer@collabora.com/ > > > > Thanks, > > Deb > > > > utils/v4l2-tracer/v4l2-tracer.cpp | 33 +++++++++++++++++-------------- > > 1 file changed, 18 insertions(+), 15 deletions(-) > > > > diff --git a/utils/v4l2-tracer/v4l2-tracer.cpp b/utils/v4l2-tracer/v4l2-tracer.cpp > > index e3f002a9..7c3662be 100644 > > --- a/utils/v4l2-tracer/v4l2-tracer.cpp > > +++ b/utils/v4l2-tracer/v4l2-tracer.cpp > > @@ -5,6 +5,7 @@ > > > > #include "retrace.h" > > #include <climits> > > +#include <sys/stat.h> > > #include <sys/wait.h> > > #include <time.h> > > > > @@ -295,24 +296,26 @@ int tracer(int argc, char *argv[], bool retrace) > > fclose(trace_file); > > > > /* > > - * Preload the libv4l2tracer library. If the program is installed, load the library > > - * from its installed location, otherwise load it locally. If it's loaded locally, > > - * use ./configure --disable-dyn-libv4l. > > + * Preload the libv4l2tracer library. The libv4l2tracer is looked up next to > > + * the executable first in order to support uninstalled build. > > */ > > std::string libv4l2tracer_path; > > std::string program = argv[0]; > > - std::size_t idx = program.rfind("/v4l2-tracer"); > > - if (idx != std::string::npos) { > > - libv4l2tracer_path = program.replace(program.begin() + idx + 1, program.end(), ".libs"); > > - DIR *directory_pointer = opendir(libv4l2tracer_path.c_str()); > > - if (directory_pointer == nullptr) > > - libv4l2tracer_path = program.replace(program.begin() + idx, program.end(), "./.libs"); > > - else > > - closedir(directory_pointer); > > - } else { > > - libv4l2tracer_path = LIBTRACER_PATH; > > - } > > - libv4l2tracer_path += "/libv4l2tracer.so"; > > + std::size_t idx = program.rfind("/"); > > + struct stat sb; > > + > > + if (idx == std::string::npos) > > + idx = 0; > > + else > > + idx++; > > + > > + /* look for libv4l2tracer next to the executable */ > > + libv4l2tracer_path = program.replace(program.begin() + idx, program.end(), "libv4l2tracer.so"); > > + > > + /* otherwise, use the installation path */ > > + if (stat(libv4l2tracer_path.c_str(), &sb) == -1) > > + libv4l2tracer_path = std::string(LIBTRACER_PATH) + "/libv4l2tracer.so"; > > + > > if (is_verbose()) > > fprintf(stderr, "Loading libv4l2tracer: %s\n", libv4l2tracer_path.c_str()); > > setenv("LD_PRELOAD", libv4l2tracer_path.c_str(), 0); >
diff --git a/utils/v4l2-tracer/v4l2-tracer.cpp b/utils/v4l2-tracer/v4l2-tracer.cpp index e3f002a9..7c3662be 100644 --- a/utils/v4l2-tracer/v4l2-tracer.cpp +++ b/utils/v4l2-tracer/v4l2-tracer.cpp @@ -5,6 +5,7 @@ #include "retrace.h" #include <climits> +#include <sys/stat.h> #include <sys/wait.h> #include <time.h> @@ -295,24 +296,26 @@ int tracer(int argc, char *argv[], bool retrace) fclose(trace_file); /* - * Preload the libv4l2tracer library. If the program is installed, load the library - * from its installed location, otherwise load it locally. If it's loaded locally, - * use ./configure --disable-dyn-libv4l. + * Preload the libv4l2tracer library. The libv4l2tracer is looked up next to + * the executable first in order to support uninstalled build. */ std::string libv4l2tracer_path; std::string program = argv[0]; - std::size_t idx = program.rfind("/v4l2-tracer"); - if (idx != std::string::npos) { - libv4l2tracer_path = program.replace(program.begin() + idx + 1, program.end(), ".libs"); - DIR *directory_pointer = opendir(libv4l2tracer_path.c_str()); - if (directory_pointer == nullptr) - libv4l2tracer_path = program.replace(program.begin() + idx, program.end(), "./.libs"); - else - closedir(directory_pointer); - } else { - libv4l2tracer_path = LIBTRACER_PATH; - } - libv4l2tracer_path += "/libv4l2tracer.so"; + std::size_t idx = program.rfind("/"); + struct stat sb; + + if (idx == std::string::npos) + idx = 0; + else + idx++; + + /* look for libv4l2tracer next to the executable */ + libv4l2tracer_path = program.replace(program.begin() + idx, program.end(), "libv4l2tracer.so"); + + /* otherwise, use the installation path */ + if (stat(libv4l2tracer_path.c_str(), &sb) == -1) + libv4l2tracer_path = std::string(LIBTRACER_PATH) + "/libv4l2tracer.so"; + if (is_verbose()) fprintf(stderr, "Loading libv4l2tracer: %s\n", libv4l2tracer_path.c_str()); setenv("LD_PRELOAD", libv4l2tracer_path.c_str(), 0);