[dpdk-dev] [PATCH 1/1] compat: fixed versioning macros

[dpdk-dev] [PATCH 1/1] compat: fixed versioning macros

[Maciej Gajdzica]

Previous version of versioning macros didn't work properly. When
building dpdk as static library, external application couldn't use
versioned function. It happened, because versioning macros for static
library were empty. Now the same version of versioning macros is used
for both static and dynamic libraries.

Signed-off-by: Maciej Gajdzica <maciejx.t.gajdzica@intel.com>
---
 lib/librte_compat/rte_compat.h |   25 +++++--------------------
 1 file changed, 5 insertions(+), 20 deletions(-)

diff --git a/lib/librte_compat/rte_compat.h b/lib/librte_compat/rte_compat.h
index fb0dc19..c5752c1 100644
--- a/lib/librte_compat/rte_compat.h
+++ b/lib/librte_compat/rte_compat.h
@@ -32,8 +32,6 @@
 #define _RTE_COMPAT_H_
 #include <rte_common.h>
 
-#ifdef RTE_BUILD_SHARED_LIB
-
 /*
  * Provides backwards compatibility when updating exported functions.
  * When a symol is exported from a library to provide an API, it also provides a
@@ -59,12 +57,14 @@
  * 3) Add this macro immediately below the function
  *	VERSION_SYMBOL(foo, _v20, 2.0);
  *
- * 4) Implement a new version of foo.
- *	char foo(int value, int otherval) { ...}
+ * 4) Implement a new version of foo with _v21 suffix.
+ *	char foo_v21(int value, int otherval) { ...}
  *
  * 5) Mark the newest version as the default version
- *	BIND_DEFAULT_SYMBOL(foo, 2.1);
+ *	BIND_DEFAULT_SYMBOL(foo, _v21, 2.1);
  *
+ * 6) Header file should contain definitions of all three
+ * functions (foo, foo_v20, foo_v21).
  */
 
 /*
@@ -96,19 +96,4 @@
 #define BIND_DEFAULT_SYMBOL(b, e, n) __asm__(".symver " RTE_STR(b) RTE_STR(e) ", "RTE_STR(b)"@@DPDK_"RTE_STR(n))
 #define __vsym __attribute__((used))
 
-#else
-/*
- * No symbol versioning in use
- */
-#define VERSION_SYMBOL(b, e, v)
-#define __vsym
-#define BASE_SYMBOL(b, n)
-#define BIND_DEFAULT_SYMBOL(b, v)
-
-/*
- * RTE_BUILD_SHARED_LIB=n
- */
-#endif
-
-
 #endif /* _RTE_COMPAT_H_ */
-- 
1.7.9.5

Re: [dpdk-dev] [dpdk-dev,1/1] compat: fixed versioning macros

[Neil Horman]

On Tue, Jun 23, 2015 at 01:38:14PM +0200, Maciej Gajdzica wrote:
> Previous version of versioning macros didn't work properly. When
> building dpdk as static library, external application couldn't use
> versioned function. It happened, because versioning macros for static
> library were empty. Now the same version of versioning macros is used
> for both static and dynamic libraries.
> 
> Signed-off-by: Maciej Gajdzica <maciejx.t.gajdzica@intel.com>
> 
> ---
> lib/librte_compat/rte_compat.h |   25 +++++--------------------
>  1 file changed, 5 insertions(+), 20 deletions(-)
> 
> diff --git a/lib/librte_compat/rte_compat.h b/lib/librte_compat/rte_compat.h
> index fb0dc19..c5752c1 100644
> --- a/lib/librte_compat/rte_compat.h
> +++ b/lib/librte_compat/rte_compat.h
> @@ -32,8 +32,6 @@
>  #define _RTE_COMPAT_H_
>  #include <rte_common.h>
>  
> -#ifdef RTE_BUILD_SHARED_LIB
> -
>  /*
>   * Provides backwards compatibility when updating exported functions.
>   * When a symol is exported from a library to provide an API, it also provides a
> @@ -59,12 +57,14 @@
>   * 3) Add this macro immediately below the function
>   *	VERSION_SYMBOL(foo, _v20, 2.0);
>   *
> - * 4) Implement a new version of foo.
> - *	char foo(int value, int otherval) { ...}
> + * 4) Implement a new version of foo with _v21 suffix.
> + *	char foo_v21(int value, int otherval) { ...}
>   *
>   * 5) Mark the newest version as the default version
> - *	BIND_DEFAULT_SYMBOL(foo, 2.1);
> + *	BIND_DEFAULT_SYMBOL(foo, _v21, 2.1);
>   *
> + * 6) Header file should contain definitions of all three
> + * functions (foo, foo_v20, foo_v21).
>   */
>  
>  /*
> @@ -96,19 +96,4 @@
>  #define BIND_DEFAULT_SYMBOL(b, e, n) __asm__(".symver " RTE_STR(b) RTE_STR(e) ", "RTE_STR(b)"@@DPDK_"RTE_STR(n))
>  #define __vsym __attribute__((used))
>  
> -#else
> -/*
> - * No symbol versioning in use
> - */
> -#define VERSION_SYMBOL(b, e, v)
> -#define __vsym
> -#define BASE_SYMBOL(b, n)
> -#define BIND_DEFAULT_SYMBOL(b, v)
> -
> -/*
> - * RTE_BUILD_SHARED_LIB=n
> - */
> -#endif
> -
> -
>  #endif /* _RTE_COMPAT_H_ */

NAK

Sorry it took me a bit to get to this, but you don't want to remove th empty
definitions from this header.  The .symver directives aren't meaningful when
doing a static build, and we don't want them to cause any odd compilation
errors.  

Neil