[libcamera-devel,v4] v4l2: v4l2_compat: Intercept open64, openat64, and mmap64

4079 diff mbox series

Some applications (eg. Firefox, Google Chrome, Skype) use open64,
openat64, and mmap64 instead of their non-64 versions that we currently
intercept. Intercept these calls as well. _LARGEFILE64_SOURCE needs to
be set so that the 64-bit symbols are available and not synonymous to
the non-64-bit versions on 64-bit systems.

Also, since we set _FILE_OFFSET_BITS to 32 to force the various open and
mmap symbols that we export to not be the 64-bit versions, our dlsym to
get the original open and mmap calls will not automatically be converted
to their 64-bit versions. Since we intercept both 32-bit and 64-bit
versions of open and mmap, we should be using the 64-bit version to
service both. Fetch the 64-bit versions of openat and mmap directly.

musl defines the 64-bit symbols as macros that are equivalent to the
non-64-bit symbols, so we put compile guards that check if the 64-bit
symbols are defined.

Signed-off-by: Paul Elder <paul.elder@ideasonboard.com>
Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
Tested-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> # Compile with musl
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

---
Changes in v4:
- fix compile guard for __open64_2 and __openat64_2 to be #ifndef open64
  and openat64, respectively

Changes in v3:
- add __open64_2 and __openat64_2

Changes in v2:
- squash intercept 64-bit calls and use 64-bit calls into
  this one patch
- use off64_t instead of __off64_t
- add compile guard to get musl to play nicely with the 64-bit calls
  coexisting with the non-64-bit calls
---
 src/v4l2/meson.build             |  1 +
 src/v4l2/v4l2_camera_proxy.cpp   |  2 +-
 src/v4l2/v4l2_camera_proxy.h     |  3 ++-
 src/v4l2/v4l2_compat.cpp         | 43 ++++++++++++++++++++++++++++++++
 src/v4l2/v4l2_compat_manager.cpp |  6 ++---
 src/v4l2/v4l2_compat_manager.h   |  5 ++--
 6 files changed, 53 insertions(+), 7 deletions(-)

Hi Paul,

On 19/06/2020 06:31, Paul Elder wrote:
> Some applications (eg. Firefox, Google Chrome, Skype) use open64,
> openat64, and mmap64 instead of their non-64 versions that we currently
> intercept. Intercept these calls as well. _LARGEFILE64_SOURCE needs to
> be set so that the 64-bit symbols are available and not synonymous to
> the non-64-bit versions on 64-bit systems.
> 
> Also, since we set _FILE_OFFSET_BITS to 32 to force the various open and
> mmap symbols that we export to not be the 64-bit versions, our dlsym to
> get the original open and mmap calls will not automatically be converted
> to their 64-bit versions. Since we intercept both 32-bit and 64-bit
> versions of open and mmap, we should be using the 64-bit version to
> service both. Fetch the 64-bit versions of openat and mmap directly.
> 
> musl defines the 64-bit symbols as macros that are equivalent to the
> non-64-bit symbols, so we put compile guards that check if the 64-bit
> symbols are defined.
> 
> Signed-off-by: Paul Elder <paul.elder@ideasonboard.com>
> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
> Tested-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> # Compile with musl
> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

Sounds good to me.

Does this now bring in functionality with those applications? or are
there still some issues pending to resolve?

Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>

> 
> ---
> Changes in v4:
> - fix compile guard for __open64_2 and __openat64_2 to be #ifndef open64
>   and openat64, respectively
> 
> Changes in v3:
> - add __open64_2 and __openat64_2
> 
> Changes in v2:
> - squash intercept 64-bit calls and use 64-bit calls into
>   this one patch
> - use off64_t instead of __off64_t
> - add compile guard to get musl to play nicely with the 64-bit calls
>   coexisting with the non-64-bit calls
> ---
>  src/v4l2/meson.build             |  1 +
>  src/v4l2/v4l2_camera_proxy.cpp   |  2 +-
>  src/v4l2/v4l2_camera_proxy.h     |  3 ++-
>  src/v4l2/v4l2_compat.cpp         | 43 ++++++++++++++++++++++++++++++++
>  src/v4l2/v4l2_compat_manager.cpp |  6 ++---
>  src/v4l2/v4l2_compat_manager.h   |  5 ++--
>  6 files changed, 53 insertions(+), 7 deletions(-)
> 
> diff --git a/src/v4l2/meson.build b/src/v4l2/meson.build
> index 0fb941e..f2e4aaf 100644
> --- a/src/v4l2/meson.build
> +++ b/src/v4l2/meson.build
> @@ -15,6 +15,7 @@ v4l2_compat_cpp_args = [
>      # file operations, disable transparent large file support.
>      '-U_FILE_OFFSET_BITS',
>      '-D_FILE_OFFSET_BITS=32',
> +    '-D_LARGEFILE64_SOURCE',
>      '-fvisibility=hidden',
>  ]
>  
> diff --git a/src/v4l2/v4l2_camera_proxy.cpp b/src/v4l2/v4l2_camera_proxy.cpp
> index 19b300f..bf47aa7 100644
> --- a/src/v4l2/v4l2_camera_proxy.cpp
> +++ b/src/v4l2/v4l2_camera_proxy.cpp
> @@ -76,7 +76,7 @@ void V4L2CameraProxy::close()
>  }
>  
>  void *V4L2CameraProxy::mmap(void *addr, size_t length, int prot, int flags,
> -			    off_t offset)
> +			    off64_t offset)
>  {
>  	LOG(V4L2Compat, Debug) << "Servicing mmap";
>  
> diff --git a/src/v4l2/v4l2_camera_proxy.h b/src/v4l2/v4l2_camera_proxy.h
> index 7c65c88..27d3e50 100644
> --- a/src/v4l2/v4l2_camera_proxy.h
> +++ b/src/v4l2/v4l2_camera_proxy.h
> @@ -11,6 +11,7 @@
>  #include <linux/videodev2.h>
>  #include <map>
>  #include <memory>
> +#include <sys/mman.h>
>  #include <sys/types.h>
>  #include <vector>
>  
> @@ -28,7 +29,7 @@ public:
>  	int open(bool nonBlocking);
>  	void dup();
>  	void close();
> -	void *mmap(void *addr, size_t length, int prot, int flags, off_t offset);
> +	void *mmap(void *addr, size_t length, int prot, int flags, off64_t offset);
>  	int munmap(void *addr, size_t length);
>  
>  	int ioctl(unsigned long request, void *arg);
> diff --git a/src/v4l2/v4l2_compat.cpp b/src/v4l2/v4l2_compat.cpp
> index 2a9a176..fd73381 100644
> --- a/src/v4l2/v4l2_compat.cpp
> +++ b/src/v4l2/v4l2_compat.cpp
> @@ -44,6 +44,23 @@ LIBCAMERA_PUBLIC int __open_2(const char *path, int oflag)
>  	return open(path, oflag);
>  }
>  
> +#ifndef open64
> +LIBCAMERA_PUBLIC int open64(const char *path, int oflag, ...)
> +{
> +	mode_t mode = 0;
> +	if (oflag & O_CREAT || oflag & O_TMPFILE)
> +		extract_va_arg(mode_t, mode, oflag);
> +
> +	return V4L2CompatManager::instance()->openat(AT_FDCWD, path,
> +						     oflag | O_LARGEFILE, mode);
> +}
> +
> +LIBCAMERA_PUBLIC int __open64_2(const char *path, int oflag)
> +{
> +	return open(path, oflag);
> +}
> +#endif
> +
>  LIBCAMERA_PUBLIC int openat(int dirfd, const char *path, int oflag, ...)
>  {
>  	mode_t mode = 0;
> @@ -58,6 +75,23 @@ LIBCAMERA_PUBLIC int __openat_2(int dirfd, const char *path, int oflag)
>  	return openat(dirfd, path, oflag);
>  }
>  
> +#ifndef openat64
> +LIBCAMERA_PUBLIC int openat64(int dirfd, const char *path, int oflag, ...)
> +{
> +	mode_t mode = 0;
> +	if (oflag & O_CREAT || oflag & O_TMPFILE)
> +		extract_va_arg(mode_t, mode, oflag);
> +
> +	return V4L2CompatManager::instance()->openat(dirfd, path,
> +						     oflag | O_LARGEFILE, mode);
> +}
> +
> +LIBCAMERA_PUBLIC int __openat64_2(int dirfd, const char *path, int oflag)
> +{
> +	return openat(dirfd, path, oflag);
> +}
> +#endif
> +
>  LIBCAMERA_PUBLIC int dup(int oldfd)
>  {
>  	return V4L2CompatManager::instance()->dup(oldfd);
> @@ -75,6 +109,15 @@ LIBCAMERA_PUBLIC void *mmap(void *addr, size_t length, int prot, int flags,
>  						   fd, offset);
>  }
>  
> +#ifndef mmap64
> +LIBCAMERA_PUBLIC void *mmap64(void *addr, size_t length, int prot, int flags,
> +			      int fd, off64_t offset)
> +{
> +	return V4L2CompatManager::instance()->mmap(addr, length, prot, flags,
> +						   fd, offset);
> +}
> +#endif
> +
>  LIBCAMERA_PUBLIC int munmap(void *addr, size_t length)
>  {
>  	return V4L2CompatManager::instance()->munmap(addr, length);
> diff --git a/src/v4l2/v4l2_compat_manager.cpp b/src/v4l2/v4l2_compat_manager.cpp
> index 56533c4..8da3316 100644
> --- a/src/v4l2/v4l2_compat_manager.cpp
> +++ b/src/v4l2/v4l2_compat_manager.cpp
> @@ -39,11 +39,11 @@ void get_symbol(T &func, const char *name)
>  V4L2CompatManager::V4L2CompatManager()
>  	: cm_(nullptr)
>  {
> -	get_symbol(fops_.openat, "openat");
> +	get_symbol(fops_.openat, "openat64");
>  	get_symbol(fops_.dup, "dup");
>  	get_symbol(fops_.close, "close");
>  	get_symbol(fops_.ioctl, "ioctl");
> -	get_symbol(fops_.mmap, "mmap");
> +	get_symbol(fops_.mmap, "mmap64");
>  	get_symbol(fops_.munmap, "munmap");
>  }
>  
> @@ -200,7 +200,7 @@ int V4L2CompatManager::close(int fd)
>  }
>  
>  void *V4L2CompatManager::mmap(void *addr, size_t length, int prot, int flags,
> -			      int fd, off_t offset)
> +			      int fd, off64_t offset)
>  {
>  	V4L2CameraProxy *proxy = getProxy(fd);
>  	if (!proxy)
> diff --git a/src/v4l2/v4l2_compat_manager.h b/src/v4l2/v4l2_compat_manager.h
> index 14338a5..3d4e512 100644
> --- a/src/v4l2/v4l2_compat_manager.h
> +++ b/src/v4l2/v4l2_compat_manager.h
> @@ -11,6 +11,7 @@
>  #include <fcntl.h>
>  #include <map>
>  #include <memory>
> +#include <sys/mman.h>
>  #include <sys/types.h>
>  #include <vector>
>  
> @@ -30,7 +31,7 @@ public:
>  		using close_func_t = int (*)(int fd);
>  		using ioctl_func_t = int (*)(int fd, unsigned long request, ...);
>  		using mmap_func_t = void *(*)(void *addr, size_t length, int prot,
> -					      int flags, int fd, off_t offset);
> +					      int flags, int fd, off64_t offset);
>  		using munmap_func_t = int (*)(void *addr, size_t length);
>  
>  		openat_func_t openat;
> @@ -51,7 +52,7 @@ public:
>  	int dup(int oldfd);
>  	int close(int fd);
>  	void *mmap(void *addr, size_t length, int prot, int flags,
> -		   int fd, off_t offset);
> +		   int fd, off64_t offset);
>  	int munmap(void *addr, size_t length);
>  	int ioctl(int fd, unsigned long request, void *arg);
>  
>

Hi Kieran,

Thank you for the review.

On Fri, Jun 19, 2020 at 10:35:37AM +0100, Kieran Bingham wrote:
> Hi Paul,
> 
> On 19/06/2020 06:31, Paul Elder wrote:
> > Some applications (eg. Firefox, Google Chrome, Skype) use open64,
> > openat64, and mmap64 instead of their non-64 versions that we currently
> > intercept. Intercept these calls as well. _LARGEFILE64_SOURCE needs to
> > be set so that the 64-bit symbols are available and not synonymous to
> > the non-64-bit versions on 64-bit systems.
> > 
> > Also, since we set _FILE_OFFSET_BITS to 32 to force the various open and
> > mmap symbols that we export to not be the 64-bit versions, our dlsym to
> > get the original open and mmap calls will not automatically be converted
> > to their 64-bit versions. Since we intercept both 32-bit and 64-bit
> > versions of open and mmap, we should be using the 64-bit version to
> > service both. Fetch the 64-bit versions of openat and mmap directly.
> > 
> > musl defines the 64-bit symbols as macros that are equivalent to the
> > non-64-bit symbols, so we put compile guards that check if the 64-bit
> > symbols are defined.
> > 
> > Signed-off-by: Paul Elder <paul.elder@ideasonboard.com>
> > Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
> > Tested-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> # Compile with musl
> > Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> 
> Sounds good to me.
> 
> Does this now bring in functionality with those applications? or are
> there still some issues pending to resolve?

Unfortunately, not yet. The patches to support v4l2-compliance gets us
most of the way there, and I think there are still a few tweaks left
needed for Firefox at least. Chrome and Skype are different beasts :/

> Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
> > 


Thanks,

Paul

> > ---
> > Changes in v4:
> > - fix compile guard for __open64_2 and __openat64_2 to be #ifndef open64
> >   and openat64, respectively
> > 
> > Changes in v3:
> > - add __open64_2 and __openat64_2
> > 
> > Changes in v2:
> > - squash intercept 64-bit calls and use 64-bit calls into
> >   this one patch
> > - use off64_t instead of __off64_t
> > - add compile guard to get musl to play nicely with the 64-bit calls
> >   coexisting with the non-64-bit calls
> > ---
> >  src/v4l2/meson.build             |  1 +
> >  src/v4l2/v4l2_camera_proxy.cpp   |  2 +-
> >  src/v4l2/v4l2_camera_proxy.h     |  3 ++-
> >  src/v4l2/v4l2_compat.cpp         | 43 ++++++++++++++++++++++++++++++++
> >  src/v4l2/v4l2_compat_manager.cpp |  6 ++---
> >  src/v4l2/v4l2_compat_manager.h   |  5 ++--
> >  6 files changed, 53 insertions(+), 7 deletions(-)
> > 
> > diff --git a/src/v4l2/meson.build b/src/v4l2/meson.build
> > index 0fb941e..f2e4aaf 100644
> > --- a/src/v4l2/meson.build
> > +++ b/src/v4l2/meson.build
> > @@ -15,6 +15,7 @@ v4l2_compat_cpp_args = [
> >      # file operations, disable transparent large file support.
> >      '-U_FILE_OFFSET_BITS',
> >      '-D_FILE_OFFSET_BITS=32',
> > +    '-D_LARGEFILE64_SOURCE',
> >      '-fvisibility=hidden',
> >  ]
> >  
> > diff --git a/src/v4l2/v4l2_camera_proxy.cpp b/src/v4l2/v4l2_camera_proxy.cpp
> > index 19b300f..bf47aa7 100644
> > --- a/src/v4l2/v4l2_camera_proxy.cpp
> > +++ b/src/v4l2/v4l2_camera_proxy.cpp
> > @@ -76,7 +76,7 @@ void V4L2CameraProxy::close()
> >  }
> >  
> >  void *V4L2CameraProxy::mmap(void *addr, size_t length, int prot, int flags,
> > -			    off_t offset)
> > +			    off64_t offset)
> >  {
> >  	LOG(V4L2Compat, Debug) << "Servicing mmap";
> >  
> > diff --git a/src/v4l2/v4l2_camera_proxy.h b/src/v4l2/v4l2_camera_proxy.h
> > index 7c65c88..27d3e50 100644
> > --- a/src/v4l2/v4l2_camera_proxy.h
> > +++ b/src/v4l2/v4l2_camera_proxy.h
> > @@ -11,6 +11,7 @@
> >  #include <linux/videodev2.h>
> >  #include <map>
> >  #include <memory>
> > +#include <sys/mman.h>
> >  #include <sys/types.h>
> >  #include <vector>
> >  
> > @@ -28,7 +29,7 @@ public:
> >  	int open(bool nonBlocking);
> >  	void dup();
> >  	void close();
> > -	void *mmap(void *addr, size_t length, int prot, int flags, off_t offset);
> > +	void *mmap(void *addr, size_t length, int prot, int flags, off64_t offset);
> >  	int munmap(void *addr, size_t length);
> >  
> >  	int ioctl(unsigned long request, void *arg);
> > diff --git a/src/v4l2/v4l2_compat.cpp b/src/v4l2/v4l2_compat.cpp
> > index 2a9a176..fd73381 100644
> > --- a/src/v4l2/v4l2_compat.cpp
> > +++ b/src/v4l2/v4l2_compat.cpp
> > @@ -44,6 +44,23 @@ LIBCAMERA_PUBLIC int __open_2(const char *path, int oflag)
> >  	return open(path, oflag);
> >  }
> >  
> > +#ifndef open64
> > +LIBCAMERA_PUBLIC int open64(const char *path, int oflag, ...)
> > +{
> > +	mode_t mode = 0;
> > +	if (oflag & O_CREAT || oflag & O_TMPFILE)
> > +		extract_va_arg(mode_t, mode, oflag);
> > +
> > +	return V4L2CompatManager::instance()->openat(AT_FDCWD, path,
> > +						     oflag | O_LARGEFILE, mode);
> > +}
> > +
> > +LIBCAMERA_PUBLIC int __open64_2(const char *path, int oflag)
> > +{
> > +	return open(path, oflag);
> > +}
> > +#endif
> > +
> >  LIBCAMERA_PUBLIC int openat(int dirfd, const char *path, int oflag, ...)
> >  {
> >  	mode_t mode = 0;
> > @@ -58,6 +75,23 @@ LIBCAMERA_PUBLIC int __openat_2(int dirfd, const char *path, int oflag)
> >  	return openat(dirfd, path, oflag);
> >  }
> >  
> > +#ifndef openat64
> > +LIBCAMERA_PUBLIC int openat64(int dirfd, const char *path, int oflag, ...)
> > +{
> > +	mode_t mode = 0;
> > +	if (oflag & O_CREAT || oflag & O_TMPFILE)
> > +		extract_va_arg(mode_t, mode, oflag);
> > +
> > +	return V4L2CompatManager::instance()->openat(dirfd, path,
> > +						     oflag | O_LARGEFILE, mode);
> > +}
> > +
> > +LIBCAMERA_PUBLIC int __openat64_2(int dirfd, const char *path, int oflag)
> > +{
> > +	return openat(dirfd, path, oflag);
> > +}
> > +#endif
> > +
> >  LIBCAMERA_PUBLIC int dup(int oldfd)
> >  {
> >  	return V4L2CompatManager::instance()->dup(oldfd);
> > @@ -75,6 +109,15 @@ LIBCAMERA_PUBLIC void *mmap(void *addr, size_t length, int prot, int flags,
> >  						   fd, offset);
> >  }
> >  
> > +#ifndef mmap64
> > +LIBCAMERA_PUBLIC void *mmap64(void *addr, size_t length, int prot, int flags,
> > +			      int fd, off64_t offset)
> > +{
> > +	return V4L2CompatManager::instance()->mmap(addr, length, prot, flags,
> > +						   fd, offset);
> > +}
> > +#endif
> > +
> >  LIBCAMERA_PUBLIC int munmap(void *addr, size_t length)
> >  {
> >  	return V4L2CompatManager::instance()->munmap(addr, length);
> > diff --git a/src/v4l2/v4l2_compat_manager.cpp b/src/v4l2/v4l2_compat_manager.cpp
> > index 56533c4..8da3316 100644
> > --- a/src/v4l2/v4l2_compat_manager.cpp
> > +++ b/src/v4l2/v4l2_compat_manager.cpp
> > @@ -39,11 +39,11 @@ void get_symbol(T &func, const char *name)
> >  V4L2CompatManager::V4L2CompatManager()
> >  	: cm_(nullptr)
> >  {
> > -	get_symbol(fops_.openat, "openat");
> > +	get_symbol(fops_.openat, "openat64");
> >  	get_symbol(fops_.dup, "dup");
> >  	get_symbol(fops_.close, "close");
> >  	get_symbol(fops_.ioctl, "ioctl");
> > -	get_symbol(fops_.mmap, "mmap");
> > +	get_symbol(fops_.mmap, "mmap64");
> >  	get_symbol(fops_.munmap, "munmap");
> >  }
> >  
> > @@ -200,7 +200,7 @@ int V4L2CompatManager::close(int fd)
> >  }
> >  
> >  void *V4L2CompatManager::mmap(void *addr, size_t length, int prot, int flags,
> > -			      int fd, off_t offset)
> > +			      int fd, off64_t offset)
> >  {
> >  	V4L2CameraProxy *proxy = getProxy(fd);
> >  	if (!proxy)
> > diff --git a/src/v4l2/v4l2_compat_manager.h b/src/v4l2/v4l2_compat_manager.h
> > index 14338a5..3d4e512 100644
> > --- a/src/v4l2/v4l2_compat_manager.h
> > +++ b/src/v4l2/v4l2_compat_manager.h
> > @@ -11,6 +11,7 @@
> >  #include <fcntl.h>
> >  #include <map>
> >  #include <memory>
> > +#include <sys/mman.h>
> >  #include <sys/types.h>
> >  #include <vector>
> >  
> > @@ -30,7 +31,7 @@ public:
> >  		using close_func_t = int (*)(int fd);
> >  		using ioctl_func_t = int (*)(int fd, unsigned long request, ...);
> >  		using mmap_func_t = void *(*)(void *addr, size_t length, int prot,
> > -					      int flags, int fd, off_t offset);
> > +					      int flags, int fd, off64_t offset);
> >  		using munmap_func_t = int (*)(void *addr, size_t length);
> >  
> >  		openat_func_t openat;
> > @@ -51,7 +52,7 @@ public:
> >  	int dup(int oldfd);
> >  	int close(int fd);
> >  	void *mmap(void *addr, size_t length, int prot, int flags,
> > -		   int fd, off_t offset);
> > +		   int fd, off64_t offset);
> >  	int munmap(void *addr, size_t length);
> >  	int ioctl(int fd, unsigned long request, void *arg);
> >  
> > 
> 
> -- 
> Regards
> --
> Kieran

Hi Paul,

On 19/06/2020 06:31, Paul Elder wrote:
> Some applications (eg. Firefox, Google Chrome, Skype) use open64,
> openat64, and mmap64 instead of their non-64 versions that we currently
> intercept. Intercept these calls as well. _LARGEFILE64_SOURCE needs to
> be set so that the 64-bit symbols are available and not synonymous to
> the non-64-bit versions on 64-bit systems.
> 
> Also, since we set _FILE_OFFSET_BITS to 32 to force the various open and
> mmap symbols that we export to not be the 64-bit versions, our dlsym to
> get the original open and mmap calls will not automatically be converted
> to their 64-bit versions. Since we intercept both 32-bit and 64-bit
> versions of open and mmap, we should be using the 64-bit version to
> service both. Fetch the 64-bit versions of openat and mmap directly.
> 
> musl defines the 64-bit symbols as macros that are equivalent to the
> non-64-bit symbols, so we put compile guards that check if the 64-bit
> symbols are defined.
> 
> Signed-off-by: Paul Elder <paul.elder@ideasonboard.com>
> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
> Tested-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> # Compile with musl
> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> 
> ---
> Changes in v4:
> - fix compile guard for __open64_2 and __openat64_2 to be #ifndef open64
>   and openat64, respectively
> 
> Changes in v3:
> - add __open64_2 and __openat64_2
> 
> Changes in v2:
> - squash intercept 64-bit calls and use 64-bit calls into
>   this one patch
> - use off64_t instead of __off64_t
> - add compile guard to get musl to play nicely with the 64-bit calls
>   coexisting with the non-64-bit calls
> ---
>  src/v4l2/meson.build             |  1 +
>  src/v4l2/v4l2_camera_proxy.cpp   |  2 +-
>  src/v4l2/v4l2_camera_proxy.h     |  3 ++-
>  src/v4l2/v4l2_compat.cpp         | 43 ++++++++++++++++++++++++++++++++
>  src/v4l2/v4l2_compat_manager.cpp |  6 ++---
>  src/v4l2/v4l2_compat_manager.h   |  5 ++--
>  6 files changed, 53 insertions(+), 7 deletions(-)
> 
> diff --git a/src/v4l2/meson.build b/src/v4l2/meson.build
> index 0fb941e..f2e4aaf 100644
> --- a/src/v4l2/meson.build
> +++ b/src/v4l2/meson.build
> @@ -15,6 +15,7 @@ v4l2_compat_cpp_args = [
>      # file operations, disable transparent large file support.
>      '-U_FILE_OFFSET_BITS',
>      '-D_FILE_OFFSET_BITS=32',
> +    '-D_LARGEFILE64_SOURCE',
>      '-fvisibility=hidden',
>  ]
>  
> diff --git a/src/v4l2/v4l2_camera_proxy.cpp b/src/v4l2/v4l2_camera_proxy.cpp
> index 19b300f..bf47aa7 100644
> --- a/src/v4l2/v4l2_camera_proxy.cpp
> +++ b/src/v4l2/v4l2_camera_proxy.cpp
> @@ -76,7 +76,7 @@ void V4L2CameraProxy::close()
>  }
>  
>  void *V4L2CameraProxy::mmap(void *addr, size_t length, int prot, int flags,
> -			    off_t offset)
> +			    off64_t offset)
>  {
>  	LOG(V4L2Compat, Debug) << "Servicing mmap";


This change has introduced the following coverity warning.

Please use the tag "Reported-by: Coverity CID=292401" if you fix this issue.

--
Kieran

> 
> New defect(s) Reported-by: Coverity Scan
> Showing 1 of 1 defect(s)
> 
> 
> ** CID 292401:  Integer handling issues  (OVERFLOW_BEFORE_WIDEN)
> /home/linuxembedded/iob/libcamera/libcamera-daily/src/v4l2/v4l2_camera_proxy.cpp: 90 in V4L2CameraProxy::mmap(void *, unsigned long, int, int, long)()
> 
> 
> ________________________________________________________________________________________________________
> *** CID 292401:  Integer handling issues  (OVERFLOW_BEFORE_WIDEN)
> /home/linuxembedded/iob/libcamera/libcamera-daily/src/v4l2/v4l2_camera_proxy.cpp: 90 in V4L2CameraProxy::mmap(void *, unsigned long, int, int, long)()
> 84     	if (prot != (PROT_READ | PROT_WRITE)) {
> 85     		errno = EINVAL;
> 86     		return MAP_FAILED;
> 87     	}
> 88     
> 89     	unsigned int index = offset / sizeimage_;
>>>>     CID 292401:  Integer handling issues  (OVERFLOW_BEFORE_WIDEN)
>>>>     Potentially overflowing expression "index * this->sizeimage_" with type "unsigned int" (32 bits, unsigned) is evaluated using 32-bit arithmetic, and then used in a context that expects an expression of type "off64_t" (64 bits, signed).
> 90     	if (static_cast<off_t>(index * sizeimage_) != offset ||
> 91     	    length != sizeimage_) {
> 92     		errno = EINVAL;
> 93     		return MAP_FAILED;
> 94     	}
> 95     

--
Kieran



>  
> diff --git a/src/v4l2/v4l2_camera_proxy.h b/src/v4l2/v4l2_camera_proxy.h
> index 7c65c88..27d3e50 100644
> --- a/src/v4l2/v4l2_camera_proxy.h
> +++ b/src/v4l2/v4l2_camera_proxy.h
> @@ -11,6 +11,7 @@
>  #include <linux/videodev2.h>
>  #include <map>
>  #include <memory>
> +#include <sys/mman.h>
>  #include <sys/types.h>
>  #include <vector>
>  
> @@ -28,7 +29,7 @@ public:
>  	int open(bool nonBlocking);
>  	void dup();
>  	void close();
> -	void *mmap(void *addr, size_t length, int prot, int flags, off_t offset);
> +	void *mmap(void *addr, size_t length, int prot, int flags, off64_t offset);
>  	int munmap(void *addr, size_t length);
>  
>  	int ioctl(unsigned long request, void *arg);
> diff --git a/src/v4l2/v4l2_compat.cpp b/src/v4l2/v4l2_compat.cpp
> index 2a9a176..fd73381 100644
> --- a/src/v4l2/v4l2_compat.cpp
> +++ b/src/v4l2/v4l2_compat.cpp
> @@ -44,6 +44,23 @@ LIBCAMERA_PUBLIC int __open_2(const char *path, int oflag)
>  	return open(path, oflag);
>  }
>  
> +#ifndef open64
> +LIBCAMERA_PUBLIC int open64(const char *path, int oflag, ...)
> +{
> +	mode_t mode = 0;
> +	if (oflag & O_CREAT || oflag & O_TMPFILE)
> +		extract_va_arg(mode_t, mode, oflag);
> +
> +	return V4L2CompatManager::instance()->openat(AT_FDCWD, path,
> +						     oflag | O_LARGEFILE, mode);
> +}
> +
> +LIBCAMERA_PUBLIC int __open64_2(const char *path, int oflag)
> +{
> +	return open(path, oflag);
> +}
> +#endif
> +
>  LIBCAMERA_PUBLIC int openat(int dirfd, const char *path, int oflag, ...)
>  {
>  	mode_t mode = 0;
> @@ -58,6 +75,23 @@ LIBCAMERA_PUBLIC int __openat_2(int dirfd, const char *path, int oflag)
>  	return openat(dirfd, path, oflag);
>  }
>  
> +#ifndef openat64
> +LIBCAMERA_PUBLIC int openat64(int dirfd, const char *path, int oflag, ...)
> +{
> +	mode_t mode = 0;
> +	if (oflag & O_CREAT || oflag & O_TMPFILE)
> +		extract_va_arg(mode_t, mode, oflag);
> +
> +	return V4L2CompatManager::instance()->openat(dirfd, path,
> +						     oflag | O_LARGEFILE, mode);
> +}
> +
> +LIBCAMERA_PUBLIC int __openat64_2(int dirfd, const char *path, int oflag)
> +{
> +	return openat(dirfd, path, oflag);
> +}
> +#endif
> +
>  LIBCAMERA_PUBLIC int dup(int oldfd)
>  {
>  	return V4L2CompatManager::instance()->dup(oldfd);
> @@ -75,6 +109,15 @@ LIBCAMERA_PUBLIC void *mmap(void *addr, size_t length, int prot, int flags,
>  						   fd, offset);
>  }
>  
> +#ifndef mmap64
> +LIBCAMERA_PUBLIC void *mmap64(void *addr, size_t length, int prot, int flags,
> +			      int fd, off64_t offset)
> +{
> +	return V4L2CompatManager::instance()->mmap(addr, length, prot, flags,
> +						   fd, offset);
> +}
> +#endif
> +
>  LIBCAMERA_PUBLIC int munmap(void *addr, size_t length)
>  {
>  	return V4L2CompatManager::instance()->munmap(addr, length);
> diff --git a/src/v4l2/v4l2_compat_manager.cpp b/src/v4l2/v4l2_compat_manager.cpp
> index 56533c4..8da3316 100644
> --- a/src/v4l2/v4l2_compat_manager.cpp
> +++ b/src/v4l2/v4l2_compat_manager.cpp
> @@ -39,11 +39,11 @@ void get_symbol(T &func, const char *name)
>  V4L2CompatManager::V4L2CompatManager()
>  	: cm_(nullptr)
>  {
> -	get_symbol(fops_.openat, "openat");
> +	get_symbol(fops_.openat, "openat64");
>  	get_symbol(fops_.dup, "dup");
>  	get_symbol(fops_.close, "close");
>  	get_symbol(fops_.ioctl, "ioctl");
> -	get_symbol(fops_.mmap, "mmap");
> +	get_symbol(fops_.mmap, "mmap64");
>  	get_symbol(fops_.munmap, "munmap");
>  }
>  
> @@ -200,7 +200,7 @@ int V4L2CompatManager::close(int fd)
>  }
>  
>  void *V4L2CompatManager::mmap(void *addr, size_t length, int prot, int flags,
> -			      int fd, off_t offset)
> +			      int fd, off64_t offset)
>  {
>  	V4L2CameraProxy *proxy = getProxy(fd);
>  	if (!proxy)
> diff --git a/src/v4l2/v4l2_compat_manager.h b/src/v4l2/v4l2_compat_manager.h
> index 14338a5..3d4e512 100644
> --- a/src/v4l2/v4l2_compat_manager.h
> +++ b/src/v4l2/v4l2_compat_manager.h
> @@ -11,6 +11,7 @@
>  #include <fcntl.h>
>  #include <map>
>  #include <memory>
> +#include <sys/mman.h>
>  #include <sys/types.h>
>  #include <vector>
>  
> @@ -30,7 +31,7 @@ public:
>  		using close_func_t = int (*)(int fd);
>  		using ioctl_func_t = int (*)(int fd, unsigned long request, ...);
>  		using mmap_func_t = void *(*)(void *addr, size_t length, int prot,
> -					      int flags, int fd, off_t offset);
> +					      int flags, int fd, off64_t offset);
>  		using munmap_func_t = int (*)(void *addr, size_t length);
>  
>  		openat_func_t openat;
> @@ -51,7 +52,7 @@ public:
>  	int dup(int oldfd);
>  	int close(int fd);
>  	void *mmap(void *addr, size_t length, int prot, int flags,
> -		   int fd, off_t offset);
> +		   int fd, off64_t offset);
>  	int munmap(void *addr, size_t length);
>  	int ioctl(int fd, unsigned long request, void *arg);
>  
>