[RFC v1 1/2] libtracefs: Use explicit libtraceevent include path

[RFC v1 1/2] libtracefs: Use explicit libtraceevent include path

[Daniel Wagner]

The libtraceevent pkg-config generated by meson is not adding the
subdirectory to the CLFAGS. This is generally a good idea in order to
avoid any file name collisions. Hence use explicit include paths for
libtraceevent.

Signed-off-by: Daniel Wagner <dwagner@suse.de>
---
 include/tracefs.h     | 2 +-
 src/tracefs-events.c  | 2 +-
 src/tracefs-filter.c  | 2 +-
 src/tracefs-sqlhist.c | 2 +-
 src/tracefs-utils.c   | 4 ++--
 5 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/include/tracefs.h b/include/tracefs.h
index 693860d47a56..dd339464ca0e 100644
--- a/include/tracefs.h
+++ b/include/tracefs.h
@@ -8,7 +8,7 @@
 
 #include <fcntl.h>
 #include <sched.h>
-#include <event-parse.h>
+#include <libtraceevent/event-parse.h>
 
 char *tracefs_get_tracing_file(const char *name);
 void tracefs_put_tracing_file(char *name);
diff --git a/src/tracefs-events.c b/src/tracefs-events.c
index 65d5707362c6..ebff59e4cb7a 100644
--- a/src/tracefs-events.c
+++ b/src/tracefs-events.c
@@ -15,7 +15,7 @@
 #include <fcntl.h>
 #include <limits.h>
 
-#include <kbuffer.h>
+#include <libtraceevent/kbuffer.h>
 
 #include "tracefs.h"
 #include "tracefs-local.h"
diff --git a/src/tracefs-filter.c b/src/tracefs-filter.c
index 85d0be17f6b7..cac4e255d7d4 100644
--- a/src/tracefs-filter.c
+++ b/src/tracefs-filter.c
@@ -6,7 +6,7 @@
  * Copyright (C) 2021, VMware, Tzvetomir Stoyanov <tz.stoyanov@gmail.com>
  *
  */
-#include <trace-seq.h>
+#include <libtraceevent/trace-seq.h>
 #include <stdlib.h>
 #include <ctype.h>
 #include <errno.h>
diff --git a/src/tracefs-sqlhist.c b/src/tracefs-sqlhist.c
index 27c9c82647e4..fbdf29d5bebb 100644
--- a/src/tracefs-sqlhist.c
+++ b/src/tracefs-sqlhist.c
@@ -6,7 +6,7 @@
  * Copyright (C) 2021, VMware, Tzvetomir Stoyanov <tz.stoyanov@gmail.com>
  *
  */
-#include <trace-seq.h>
+#include <libtraceevent/trace-seq.h>
 #include <stdlib.h>
 #include <stdarg.h>
 #include <ctype.h>
diff --git a/src/tracefs-utils.c b/src/tracefs-utils.c
index 22f82afe032b..c1260d3c7c8a 100644
--- a/src/tracefs-utils.c
+++ b/src/tracefs-utils.c
@@ -15,8 +15,8 @@
 #include <unistd.h>
 #include <errno.h>
 
-#include <event-parse.h>
-#include <event-utils.h>
+#include <libtraceevent/event-parse.h>
+#include <libtraceevent/event-utils.h>
 #include "tracefs.h"
 #include "tracefs-local.h"
 
-- 
2.36.1

[RFC v1 2/2] libtracefs: Add initial support for meson

[Daniel Wagner]

Add support for building the project with meson. It's not complete
yet, for example building and installing the documentation is missing.

The rest should work as expected. The only thing I was not really
clear what the purpose is the libtraceevent-dynamic-list which seems
not be used or installed. The meson build will also generate the file
but using the host nm and not the cross tool chain if any is used. I
didn't want to invest too much time figuring out this detail if it is
actually not used.

Obviously, meson is not make and there are some changes in how to use
this build system. The meson documentation is outstanding good and
usually has good tips and tricks to solve problems. But sure there is
learning curve but hopefully not so step.

Anyway, as pure user the build steps are (in source tree builds are
not supported):

  # configure using .build as build directory and install destination
  # /tmp/test
  meson .build --prefix=/tmp/test

  # trigger the build
  ninja -C .build

  # install the library
  ninja -C .build install

I am using an alias for 'ninja -C .build' which is called 'ni'. This
makes way more convenient to use.

Signed-off-by: Daniel Wagner <dwagner@suse.de>
---
 include/meson.build |  9 ++++++++
 meson.build         | 32 +++++++++++++++++++++++++++
 src/meson.build     | 53 +++++++++++++++++++++++++++++++++++++++++++++
 utest/meson.build   | 14 ++++++++++++
 4 files changed, 108 insertions(+)
 create mode 100644 include/meson.build
 create mode 100644 meson.build
 create mode 100644 src/meson.build
 create mode 100644 utest/meson.build

diff --git a/include/meson.build b/include/meson.build
new file mode 100644
index 000000000000..1bbfe8afb280
--- /dev/null
+++ b/include/meson.build
@@ -0,0 +1,9 @@
+# SPDX-License-Identifier: LGPL-2.1
+
+headers = [
+   'tracefs.h',
+]
+
+foreach h : headers
+	install_headers(h, subdir : 'libtracefs')
+endforeach
diff --git a/meson.build b/meson.build
new file mode 100644
index 000000000000..2138d2f149f1
--- /dev/null
+++ b/meson.build
@@ -0,0 +1,32 @@
+# SPDX-License-Identifier: LGPL-2.1
+
+project(
+    'libtracefs', ['c'],
+    meson_version: '>= 0.47.0',
+    license: 'LGPL-2.1',
+    version: '1.4.0',
+    default_options: [
+      'c_std=gnu99',
+      'buildtype=release',
+      'prefix=/usr',
+      'warning_level=1',
+    ]
+)
+
+library_version = meson.project_version()
+
+libtraceevent_dep = dependency('libtraceevent', required: true)
+cunit_dep = dependency('cunit', required : false)
+
+add_project_arguments(
+    [
+      '-D_GNU_SOURCE',
+    ],
+    language : 'c',
+)
+
+incdir = include_directories(['include'])
+
+subdir('src')
+subdir('include')
+subdir('utest')
diff --git a/src/meson.build b/src/meson.build
new file mode 100644
index 000000000000..36d3be359fae
--- /dev/null
+++ b/src/meson.build
@@ -0,0 +1,53 @@
+# SPDX-License-Identifier: LGPL-2.1
+
+sources= [
+   'tracefs-dynevents.c',
+   'tracefs-eprobes.c',
+   'tracefs-events.c',
+   'tracefs-filter.c',
+   'tracefs-hist.c',
+   'tracefs-instance.c',
+   'tracefs-kprobes.c',
+   'tracefs-marker.c',
+   'tracefs-sqlhist.c',
+   'tracefs-tools.c',
+   'tracefs-uprobes.c',
+   'tracefs-utils.c',
+]
+
+flex = find_program('flex', required: true)
+bison = find_program('bison', required: true)
+
+lgen = generator(flex,
+output : '@PLAINNAME@.yy.c',
+arguments : ['-o', '@OUTPUT@', '@INPUT@'])
+
+pgen = generator(bison,
+output : ['@BASENAME@.tab.c', '@BASENAME@.tab.h'],
+arguments : ['@INPUT@', '--defines=@OUTPUT1@', '--output=@OUTPUT0@'])
+
+lfiles = lgen.process('sqlhist.l')
+pfiles = pgen.process('sqlhist.y')
+
+libtracefs = library(
+    'tracefs',
+    sources, lfiles, pfiles,
+    version: library_version,
+    dependencies: [libtraceevent_dep],
+    include_directories: [incdir],
+    install: true,
+)
+
+pkg = import('pkgconfig')
+pkg.generate(libtracefs,
+    filebase: meson.project_name(),
+    name: meson.project_name(),
+    version: meson.project_version(),
+    description: 'Manage trace fs',
+    url: 'https://git.kernel.org/pub/scm/libs/libtrace/libtracefs.git/',
+)
+
+libtracefs_dep = declare_dependency(
+    include_directories: ['.'],
+    link_with: libtracefs,
+)
diff --git a/utest/meson.build b/utest/meson.build
new file mode 100644
index 000000000000..07058afb5f9b
--- /dev/null
+++ b/utest/meson.build
@@ -0,0 +1,14 @@
+# SPDX-License-Identifier: LGPL-2.1
+
+source = [
+    'trace-utest.c',
+    'tracefs-utest.c',
+]
+
+e = executable(
+   'trace-utest',
+   source,
+   include_directories: [incdir],
+   dependencies: [libtracefs_dep, libtraceevent_dep, cunit_dep])
+
+test('trace-utest', e)
-- 
2.36.1

Re: [RFC v1 1/2] libtracefs: Use explicit libtraceevent include path

[Steven Rostedt]

On Thu,  7 Jul 2022 14:15:41 +0200
Daniel Wagner <dwagner@suse.de> wrote:

> The libtraceevent pkg-config generated by meson is not adding the
> subdirectory to the CLFAGS. This is generally a good idea in order to
> avoid any file name collisions. Hence use explicit include paths for
> libtraceevent.

Is there a way to fix this. Honestly, I hate the libtraceevent name (should
at least be traceevent), and I have been thinking of changing it.

If we do not have pkg-config working and everything needs to add explicit
include paths, then I'll never be able to change it, or even just get rid
of the subdirectory.

-- Steve

Re: [RFC v1 1/2] libtracefs: Use explicit libtraceevent include path

[Daniel Wagner]

On Thu, Jul 07, 2022 at 09:47:52AM -0400, Steven Rostedt wrote:
> On Thu,  7 Jul 2022 14:15:41 +0200
> Daniel Wagner <dwagner@suse.de> wrote:
> 
> > The libtraceevent pkg-config generated by meson is not adding the
> > subdirectory to the CLFAGS. This is generally a good idea in order to
> > avoid any file name collisions. Hence use explicit include paths for
> > libtraceevent.
> 
> Is there a way to fix this. Honestly, I hate the libtraceevent name (should
> at least be traceevent), and I have been thinking of changing it.

I suppose we can change pkg-config so that the complete path is
included, with the downside that file name collisions are more likely to
happen. E.g. the kbuffer.h is very a generic name.

In libnvme/nvme-cli we had some troubles consuming libuuid because of
inconsistent use of include paths. As far I can tell we just need to
state what the correct includes paths are.

> If we do not have pkg-config working and everything needs to add explicit
> include paths, then I'll never be able to change it, or even just get rid
> of the subdirectory.

I am not really expert how to structure the include paths. As said, I
think the most important bit is that we use it consistent. Let me try to
add the include path to pkg-config.

Re: [RFC v1 1/2] libtracefs: Use explicit libtraceevent include path

[Steven Rostedt]

On Thu, 7 Jul 2022 16:07:23 +0200
Daniel Wagner <dwagner@suse.de> wrote:

> On Thu, Jul 07, 2022 at 09:47:52AM -0400, Steven Rostedt wrote:
> > On Thu,  7 Jul 2022 14:15:41 +0200
> > Daniel Wagner <dwagner@suse.de> wrote:
> >   
> > > The libtraceevent pkg-config generated by meson is not adding the
> > > subdirectory to the CLFAGS. This is generally a good idea in order to
> > > avoid any file name collisions. Hence use explicit include paths for
> > > libtraceevent.  
> > 
> > Is there a way to fix this. Honestly, I hate the libtraceevent name (should
> > at least be traceevent), and I have been thinking of changing it.  
> 
> I suppose we can change pkg-config so that the complete path is
> included, with the downside that file name collisions are more likely to
> happen. E.g. the kbuffer.h is very a generic name.

Sorta-of ;-)  That's actually the file I want to "claim" first!

> 
> In libnvme/nvme-cli we had some troubles consuming libuuid because of
> inconsistent use of include paths. As far I can tell we just need to
> state what the correct includes paths are.
> 
> > If we do not have pkg-config working and everything needs to add explicit
> > include paths, then I'll never be able to change it, or even just get rid
> > of the subdirectory.  
> 
> I am not really expert how to structure the include paths. As said, I
> think the most important bit is that we use it consistent. Let me try to
> add the include path to pkg-config.

Thanks,

-- Steve