[2/4] libcamera: shared_mem_object: Fix compilation with uClibc

19993 diff mbox series

uClibc doesn't provide a memfd_create() implementation. Fix it by using
a direct syscall when the function isn't available.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
---
 meson.build                         | 4 ++++
 src/libcamera/shared_mem_object.cpp | 6 ++++++
 2 files changed, 10 insertions(+)

Hi Laurent,

Thank you for the patch

On 03/05/24 8:22 am, Laurent Pinchart wrote:
> uClibc doesn't provide a memfd_create() implementation. Fix it by using
> a direct syscall when the function isn't available.
>
> Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

Reviewed-by: Umang Jain <umang.jain@ideasonboard.com>
> ---
>   meson.build                         | 4 ++++
>   src/libcamera/shared_mem_object.cpp | 6 ++++++
>   2 files changed, 10 insertions(+)
>
> diff --git a/meson.build b/meson.build
> index 740ead1be85f..39e4947f8c97 100644
> --- a/meson.build
> +++ b/meson.build
> @@ -82,6 +82,10 @@ if cc.has_header_symbol('locale.h', 'locale_t', prefix : '#define _GNU_SOURCE')
>       config_h.set('HAVE_LOCALE_T', 1)
>   endif
>   
> +if cc.has_header_symbol('sys/mman.h', 'memfd_create', prefix : '#define _GNU_SOURCE')
> +    config_h.set('HAVE_MEMFD_CREATE', 1)
> +endif
> +
>   if cc.has_header_symbol('stdlib.h', 'secure_getenv', prefix : '#define _GNU_SOURCE')
>       config_h.set('HAVE_SECURE_GETENV', 1)
>   endif
> diff --git a/src/libcamera/shared_mem_object.cpp b/src/libcamera/shared_mem_object.cpp
> index b018fb3bc0a5..e8cb59f7a90f 100644
> --- a/src/libcamera/shared_mem_object.cpp
> +++ b/src/libcamera/shared_mem_object.cpp
> @@ -12,6 +12,8 @@
>   
>   #include <stddef.h>
>   #include <stdint.h>
> +#include <sys/mman.h>
> +#include <sys/syscall.h>
>   #include <sys/types.h>
>   #include <unistd.h>
>   
> @@ -56,7 +58,11 @@ SharedMem::SharedMem() = default;
>    */
>   SharedMem::SharedMem(const std::string &name, std::size_t size)
>   {
> +#if HAVE_MEMFD_CREATE
>   	int fd = memfd_create(name.c_str(), MFD_CLOEXEC);
> +#else
> +	int fd = syscall(SYS_memfd_create, name.c_str(), MFD_CLOEXEC);
> +#endif
>   	if (fd < 0)
>   		return;
>

Hi Laurent,

thanks for the patch.

On Fri, May 03, 2024 at 05:52:03AM +0300, Laurent Pinchart wrote:
> uClibc doesn't provide a memfd_create() implementation. Fix it by using

Ahh that answeres my previous question :-)

> a direct syscall when the function isn't available.
> 
> Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

Reviewed-by: Stefan Klug <stefan.klug@ideasonboard.com> 

Cheers,
Stefan

> ---
>  meson.build                         | 4 ++++
>  src/libcamera/shared_mem_object.cpp | 6 ++++++
>  2 files changed, 10 insertions(+)
> 
> diff --git a/meson.build b/meson.build
> index 740ead1be85f..39e4947f8c97 100644
> --- a/meson.build
> +++ b/meson.build
> @@ -82,6 +82,10 @@ if cc.has_header_symbol('locale.h', 'locale_t', prefix : '#define _GNU_SOURCE')
>      config_h.set('HAVE_LOCALE_T', 1)
>  endif
>  
> +if cc.has_header_symbol('sys/mman.h', 'memfd_create', prefix : '#define _GNU_SOURCE')
> +    config_h.set('HAVE_MEMFD_CREATE', 1)
> +endif
> +
>  if cc.has_header_symbol('stdlib.h', 'secure_getenv', prefix : '#define _GNU_SOURCE')
>      config_h.set('HAVE_SECURE_GETENV', 1)
>  endif
> diff --git a/src/libcamera/shared_mem_object.cpp b/src/libcamera/shared_mem_object.cpp
> index b018fb3bc0a5..e8cb59f7a90f 100644
> --- a/src/libcamera/shared_mem_object.cpp
> +++ b/src/libcamera/shared_mem_object.cpp
> @@ -12,6 +12,8 @@
>  
>  #include <stddef.h>
>  #include <stdint.h>
> +#include <sys/mman.h>
> +#include <sys/syscall.h>
>  #include <sys/types.h>
>  #include <unistd.h>
>  
> @@ -56,7 +58,11 @@ SharedMem::SharedMem() = default;
>   */
>  SharedMem::SharedMem(const std::string &name, std::size_t size)
>  {
> +#if HAVE_MEMFD_CREATE
>  	int fd = memfd_create(name.c_str(), MFD_CLOEXEC);
> +#else
> +	int fd = syscall(SYS_memfd_create, name.c_str(), MFD_CLOEXEC);
> +#endif
>  	if (fd < 0)
>  		return;
>  
> -- 
> Regards,
> 
> Laurent Pinchart
>