[v6,3/5] eal: make OS shims internal

Message ID 20210320130525.16452-4-dmitry.kozliuk@gmail.com (mailing list archive)
State Superseded, archived
Delegated to: David Marchand
Headers
Series eal/windows: do not expose POSIX symbols |

Checks

Context Check Description
ci/checkpatch success coding style OK

Commit Message

Dmitry Kozlyuk March 20, 2021, 1:05 p.m. UTC
  DPDK code often relies on functions and macros that are not standard C,
but are found on all platforms, even if by slightly different names.
Windows <rte_os.h> provided macros or inline definitions for such symbols.
However, when placed in public header, these symbols were unnecessarily
exposed, breaking consumer POSIX compatibility code.

Move all shims to <rte_os_internal.h>, a header to be used instead of
<rte_os.h> by internal code. Include it in libraries and PMDs that
previously imported shims from <rte_os.h>.

Signed-off-by: Dmitry Kozlyuk <dmitry.kozliuk@gmail.com>
---
 drivers/bus/pci/private.h                     |  4 +-
 drivers/bus/vdev/vdev_private.h               |  2 +
 drivers/common/mlx5/mlx5_common.h             |  1 +
 drivers/net/i40e/i40e_ethdev.c                |  1 +
 lib/librte_cmdline/cmdline.c                  |  4 -
 lib/librte_cmdline/cmdline_os_windows.c       |  2 -
 lib/librte_cmdline/cmdline_private.h          |  1 +
 lib/librte_cmdline/cmdline_socket.c           |  4 -
 lib/librte_eal/common/eal_common_config.c     |  1 -
 lib/librte_eal/common/eal_common_errno.c      |  4 +
 lib/librte_eal/common/eal_common_options.c    |  2 +-
 lib/librte_eal/common/eal_internal_cfg.h      |  1 +
 .../freebsd/include/rte_os_internal.h         | 14 +++
 .../linux/include/rte_os_internal.h           | 14 +++
 lib/librte_eal/windows/eal_hugepages.c        |  1 -
 lib/librte_eal/windows/eal_lcore.c            |  1 -
 lib/librte_eal/windows/eal_memalloc.c         |  1 -
 lib/librte_eal/windows/include/rte_os.h       | 92 +------------------
 .../windows/include/rte_os_internal.h         | 28 ++++++
 lib/librte_ethdev/ethdev_private.h            |  2 +
 lib/librte_kvargs/rte_kvargs.c                |  1 +
 21 files changed, 77 insertions(+), 104 deletions(-)
 create mode 100644 lib/librte_eal/freebsd/include/rte_os_internal.h
 create mode 100644 lib/librte_eal/linux/include/rte_os_internal.h
 create mode 100644 lib/librte_eal/windows/include/rte_os_internal.h
  

Comments

Thomas Monjalon March 26, 2021, 9:12 a.m. UTC | #1
20/03/2021 14:05, Dmitry Kozlyuk:
> DPDK code often relies on functions and macros that are not standard C,
> but are found on all platforms, even if by slightly different names.
> Windows <rte_os.h> provided macros or inline definitions for such symbols.
> However, when placed in public header, these symbols were unnecessarily
> exposed, breaking consumer POSIX compatibility code.
> 
> Move all shims to <rte_os_internal.h>, a header to be used instead of
> <rte_os.h> by internal code. Include it in libraries and PMDs that
> previously imported shims from <rte_os.h>.

This shim could have been convenient for applications.
If not named "internal", we could export the header file
and allow apps including it.

Otherwise the app can recreate this file on its side,
it is not a big deal.
Opinions?
  
Nick Connolly March 31, 2021, 9:05 p.m. UTC | #2
> This shim could have been convenient for applications.
> If not named "internal", we could export the header file
> and allow apps including it.
>
> Otherwise the app can recreate this file on its side,
> it is not a big deal.
> Opinions?
Based on my experience with SPDK, I believe this would get messy
very quickly.

For example, a common usage is to redefine close to _close.
If the application is going to use sockets without requiring changes,
then a fake fd is needed to represent a socket and close has to
handle it as well ... which will clash with the 'simplistic' redefinition
to _close, so we'd need some way of turning these on/off
individually.

I think there are really only two models that are viable - either an
external POSIX layer that is used by everything (in the general case,
Cygwin would be an example), or a private implementation that is
not exposed publicly.

Keeping the implementation private is not just about keeping
POSIX out of the headers. It's about avoiding conflicts with the
application; e.g. making sure that any signal implementation can
co-exist with the application.

Regards,
Nick
  
Thomas Monjalon March 31, 2021, 9:19 p.m. UTC | #3
31/03/2021 23:05, Nick Connolly:
> 
> > This shim could have been convenient for applications.
> > If not named "internal", we could export the header file
> > and allow apps including it.
> >
> > Otherwise the app can recreate this file on its side,
> > it is not a big deal.
> > Opinions?
> Based on my experience with SPDK, I believe this would get messy
> very quickly.
> 
> For example, a common usage is to redefine close to _close.
> If the application is going to use sockets without requiring changes,
> then a fake fd is needed to represent a socket and close has to
> handle it as well ... which will clash with the 'simplistic' redefinition
> to _close, so we'd need some way of turning these on/off
> individually.
> 
> I think there are really only two models that are viable - either an
> external POSIX layer that is used by everything (in the general case,
> Cygwin would be an example), or a private implementation that is
> not exposed publicly.
> 
> Keeping the implementation private is not just about keeping
> POSIX out of the headers. It's about avoiding conflicts with the
> application; e.g. making sure that any signal implementation can
> co-exist with the application.

I don't understand your point.
I am just proposing to allow some apps to explicitly include the shim
for their convenience in case they are fully based on DPDK and
understand the risk of conflict with some other code.
  
Nick Connolly March 31, 2021, 9:45 p.m. UTC | #4
>
> I don't understand your point.
> I am just proposing to allow some apps to explicitly include the shim
> for their convenience in case they are fully based on DPDK and
> understand the risk of conflict with some other code.


Agreed - there’s no harm in doing so.

My point was simply that for a non-trivial application I suspect it will
have limited value due to the sorts of conflicts that are likely to arise.

Regards,
Nick

>
  
Thomas Monjalon March 31, 2021, 9:55 p.m. UTC | #5
31/03/2021 23:45, Nick Connolly:
> >
> > I don't understand your point.
> > I am just proposing to allow some apps to explicitly include the shim
> > for their convenience in case they are fully based on DPDK and
> > understand the risk of conflict with some other code.
> 
> 
> Agreed - there’s no harm in doing so.
> 
> My point was simply that for a non-trivial application I suspect it will
> have limited value due to the sorts of conflicts that are likely to arise.

OK yes.
If we expose this header, we should bring it with a disclaimer.
  
Dmitry Kozlyuk April 1, 2021, 11:10 p.m. UTC | #6
2021-03-31 23:55 (UTC+0200), Thomas Monjalon:
> 31/03/2021 23:45, Nick Connolly:
> > >
> > > I don't understand your point.
> > > I am just proposing to allow some apps to explicitly include the shim
> > > for their convenience in case they are fully based on DPDK and
> > > understand the risk of conflict with some other code.  
> > 
> > 
> > Agreed - there’s no harm in doing so.
> > 
> > My point was simply that for a non-trivial application I suspect it will
> > have limited value due to the sorts of conflicts that are likely to arise.  
> 
> OK yes.
> If we expose this header, we should bring it with a disclaimer.

Let's now avoid "internal" (rte_os_shim?), but expose it later, if ever:

1. The concept of "not so public" API is new, probably a techboard subject.
2. We may want devtools checks against including it from public headers.
  
Thomas Monjalon April 1, 2021, 11:18 p.m. UTC | #7
02/04/2021 01:10, Dmitry Kozlyuk:
> 2021-03-31 23:55 (UTC+0200), Thomas Monjalon:
> > 31/03/2021 23:45, Nick Connolly:
> > > >
> > > > I don't understand your point.
> > > > I am just proposing to allow some apps to explicitly include the shim
> > > > for their convenience in case they are fully based on DPDK and
> > > > understand the risk of conflict with some other code.  
> > > 
> > > 
> > > Agreed - there’s no harm in doing so.
> > > 
> > > My point was simply that for a non-trivial application I suspect it will
> > > have limited value due to the sorts of conflicts that are likely to arise.  
> > 
> > OK yes.
> > If we expose this header, we should bring it with a disclaimer.
> 
> Let's now avoid "internal" (rte_os_shim?), but expose it later, if ever:
> 
> 1. The concept of "not so public" API is new, probably a techboard subject.
> 2. We may want devtools checks against including it from public headers.

Yes it should be well discussed and checked with scripts.
For now, let's not expose such shim, but as you said,
adopt a more descriptive name avoiding "internal" qualifier.
  

Patch

diff --git a/drivers/bus/pci/private.h b/drivers/bus/pci/private.h
index f566943f5e..d95e6f71a2 100644
--- a/drivers/bus/pci/private.h
+++ b/drivers/bus/pci/private.h
@@ -7,8 +7,10 @@ 
 
 #include <stdbool.h>
 #include <stdio.h>
-#include <rte_pci.h>
+
 #include <rte_bus_pci.h>
+#include <rte_os_internal.h>
+#include <rte_pci.h>
 
 extern struct rte_pci_bus rte_pci_bus;
 
diff --git a/drivers/bus/vdev/vdev_private.h b/drivers/bus/vdev/vdev_private.h
index ba6dc48ff3..1a60c1b5d2 100644
--- a/drivers/bus/vdev/vdev_private.h
+++ b/drivers/bus/vdev/vdev_private.h
@@ -5,6 +5,8 @@ 
 #ifndef _VDEV_PRIVATE_H_
 #define _VDEV_PRIVATE_H_
 
+#include <rte_os_internal.h>
+
 #ifdef __cplusplus
 extern "C" {
 #endif
diff --git a/drivers/common/mlx5/mlx5_common.h b/drivers/common/mlx5/mlx5_common.h
index 3855582d0d..14b061690f 100644
--- a/drivers/common/mlx5/mlx5_common.h
+++ b/drivers/common/mlx5/mlx5_common.h
@@ -14,6 +14,7 @@ 
 #include <rte_kvargs.h>
 #include <rte_devargs.h>
 #include <rte_bitops.h>
+#include <rte_os_internal.h>
 
 #include "mlx5_prm.h"
 #include "mlx5_devx_cmds.h"
diff --git a/drivers/net/i40e/i40e_ethdev.c b/drivers/net/i40e/i40e_ethdev.c
index d7cd049891..0719504e24 100644
--- a/drivers/net/i40e/i40e_ethdev.c
+++ b/drivers/net/i40e/i40e_ethdev.c
@@ -27,6 +27,7 @@ 
 #include <rte_tailq.h>
 #include <rte_hash_crc.h>
 #include <rte_bitmap.h>
+#include <rte_os_internal.h>
 
 #include "i40e_logs.h"
 #include "base/i40e_prototype.h"
diff --git a/lib/librte_cmdline/cmdline.c b/lib/librte_cmdline/cmdline.c
index 79ea5f98c8..49770869bb 100644
--- a/lib/librte_cmdline/cmdline.c
+++ b/lib/librte_cmdline/cmdline.c
@@ -18,10 +18,6 @@ 
 
 #include "cmdline_private.h"
 
-#ifdef RTE_EXEC_ENV_WINDOWS
-#define write _write
-#endif
-
 static void
 cmdline_valid_buffer(struct rdline *rdl, const char *buf,
 		     __rte_unused unsigned int size)
diff --git a/lib/librte_cmdline/cmdline_os_windows.c b/lib/librte_cmdline/cmdline_os_windows.c
index e9585c9eea..73ed9ba290 100644
--- a/lib/librte_cmdline/cmdline_os_windows.c
+++ b/lib/librte_cmdline/cmdline_os_windows.c
@@ -4,8 +4,6 @@ 
 
 #include <io.h>
 
-#include <rte_os.h>
-
 #include "cmdline_private.h"
 
 /* Missing from some MinGW-w64 distributions. */
diff --git a/lib/librte_cmdline/cmdline_private.h b/lib/librte_cmdline/cmdline_private.h
index a8a6ee9e69..ca45db9493 100644
--- a/lib/librte_cmdline/cmdline_private.h
+++ b/lib/librte_cmdline/cmdline_private.h
@@ -8,6 +8,7 @@ 
 #include <stdarg.h>
 
 #include <rte_common.h>
+#include <rte_os_internal.h>
 #ifdef RTE_EXEC_ENV_WINDOWS
 #include <rte_windows.h>
 #endif
diff --git a/lib/librte_cmdline/cmdline_socket.c b/lib/librte_cmdline/cmdline_socket.c
index 0fe1497008..998e8ade25 100644
--- a/lib/librte_cmdline/cmdline_socket.c
+++ b/lib/librte_cmdline/cmdline_socket.c
@@ -16,10 +16,6 @@ 
 #include "cmdline_private.h"
 #include "cmdline_socket.h"
 
-#ifdef RTE_EXEC_ENV_WINDOWS
-#define open _open
-#endif
-
 struct cmdline *
 cmdline_file_new(cmdline_parse_ctx_t *ctx, const char *prompt, const char *path)
 {
diff --git a/lib/librte_eal/common/eal_common_config.c b/lib/librte_eal/common/eal_common_config.c
index 56d09dda7f..1c4c4dd585 100644
--- a/lib/librte_eal/common/eal_common_config.c
+++ b/lib/librte_eal/common/eal_common_config.c
@@ -3,7 +3,6 @@ 
  */
 #include <string.h>
 
-#include <rte_os.h>
 #include <rte_string_fns.h>
 
 #include "eal_private.h"
diff --git a/lib/librte_eal/common/eal_common_errno.c b/lib/librte_eal/common/eal_common_errno.c
index 2a10fb823f..f86802705a 100644
--- a/lib/librte_eal/common/eal_common_errno.c
+++ b/lib/librte_eal/common/eal_common_errno.c
@@ -15,6 +15,10 @@ 
 #include <rte_errno.h>
 #include <rte_string_fns.h>
 
+#ifdef RTE_EXEC_ENV_WINDOWS
+#define strerror_r(errnum, buf, buflen) strerror_s(buf, buflen, errnum)
+#endif
+
 RTE_DEFINE_PER_LCORE(int, _rte_errno);
 
 const char *
diff --git a/lib/librte_eal/common/eal_common_options.c b/lib/librte_eal/common/eal_common_options.c
index 622c7bc429..28da464fc9 100644
--- a/lib/librte_eal/common/eal_common_options.c
+++ b/lib/librte_eal/common/eal_common_options.c
@@ -1936,7 +1936,7 @@  eal_check_common_options(struct internal_config *internal_cfg)
 		RTE_LOG(ERR, EAL, "Invalid length of --" OPT_MBUF_POOL_OPS_NAME" option\n");
 		return -1;
 	}
-	if (index(eal_get_hugefile_prefix(), '%') != NULL) {
+	if (strchr(eal_get_hugefile_prefix(), '%') != NULL) {
 		RTE_LOG(ERR, EAL, "Invalid char, '%%', in --"OPT_FILE_PREFIX" "
 			"option\n");
 		return -1;
diff --git a/lib/librte_eal/common/eal_internal_cfg.h b/lib/librte_eal/common/eal_internal_cfg.h
index 51dbe86e2b..fc7cb3efaf 100644
--- a/lib/librte_eal/common/eal_internal_cfg.h
+++ b/lib/librte_eal/common/eal_internal_cfg.h
@@ -11,6 +11,7 @@ 
 #define EAL_INTERNAL_CFG_H
 
 #include <rte_eal.h>
+#include <rte_os_internal.h>
 #include <rte_pci_dev_feature_defs.h>
 
 #include "eal_thread.h"
diff --git a/lib/librte_eal/freebsd/include/rte_os_internal.h b/lib/librte_eal/freebsd/include/rte_os_internal.h
new file mode 100644
index 0000000000..cabe9648fa
--- /dev/null
+++ b/lib/librte_eal/freebsd/include/rte_os_internal.h
@@ -0,0 +1,14 @@ 
+/* SPDX-License-Identifier: BSD-3-Clause */
+
+#ifndef _RTE_OS_INTERNAL_H_
+#define _RTE_OS_INTERNAL_H_
+
+#include <rte_os.h>
+
+/**
+ * @file
+ * @internal
+ * Provides semi-standard OS facilities by convenient names.
+ */
+
+#endif /* _RTE_OS_INTERNAL_H_ */
diff --git a/lib/librte_eal/linux/include/rte_os_internal.h b/lib/librte_eal/linux/include/rte_os_internal.h
new file mode 100644
index 0000000000..cabe9648fa
--- /dev/null
+++ b/lib/librte_eal/linux/include/rte_os_internal.h
@@ -0,0 +1,14 @@ 
+/* SPDX-License-Identifier: BSD-3-Clause */
+
+#ifndef _RTE_OS_INTERNAL_H_
+#define _RTE_OS_INTERNAL_H_
+
+#include <rte_os.h>
+
+/**
+ * @file
+ * @internal
+ * Provides semi-standard OS facilities by convenient names.
+ */
+
+#endif /* _RTE_OS_INTERNAL_H_ */
diff --git a/lib/librte_eal/windows/eal_hugepages.c b/lib/librte_eal/windows/eal_hugepages.c
index 83a3d0ffc6..b007dceb39 100644
--- a/lib/librte_eal/windows/eal_hugepages.c
+++ b/lib/librte_eal/windows/eal_hugepages.c
@@ -6,7 +6,6 @@ 
 #include <rte_log.h>
 #include <rte_memory.h>
 #include <rte_memzone.h>
-#include <rte_os.h>
 
 #include "eal_private.h"
 #include "eal_filesystem.h"
diff --git a/lib/librte_eal/windows/eal_lcore.c b/lib/librte_eal/windows/eal_lcore.c
index a85149be95..476c2d2bdf 100644
--- a/lib/librte_eal/windows/eal_lcore.c
+++ b/lib/librte_eal/windows/eal_lcore.c
@@ -9,7 +9,6 @@ 
 #include <rte_common.h>
 #include <rte_debug.h>
 #include <rte_lcore.h>
-#include <rte_os.h>
 
 #include "eal_private.h"
 #include "eal_thread.h"
diff --git a/lib/librte_eal/windows/eal_memalloc.c b/lib/librte_eal/windows/eal_memalloc.c
index 85a9712cea..4459d59b1a 100644
--- a/lib/librte_eal/windows/eal_memalloc.c
+++ b/lib/librte_eal/windows/eal_memalloc.c
@@ -3,7 +3,6 @@ 
  */
 
 #include <rte_errno.h>
-#include <rte_os.h>
 
 #include "eal_internal_cfg.h"
 #include "eal_memalloc.h"
diff --git a/lib/librte_eal/windows/include/rte_os.h b/lib/librte_eal/windows/include/rte_os.h
index 7ef38ff06c..8d845c57b7 100644
--- a/lib/librte_eal/windows/include/rte_os.h
+++ b/lib/librte_eal/windows/include/rte_os.h
@@ -11,7 +11,6 @@ 
  * Windows OS. It must not include Windows-specific headers.
  */
 
-#include <stdarg.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -20,101 +19,18 @@ 
 extern "C" {
 #endif
 
-/* limits.h replacement, value as in <windows.h> */
-#ifndef PATH_MAX
-#define PATH_MAX _MAX_PATH
-#endif
-
-#ifndef sleep
-#define sleep(x) Sleep(1000 * (x))
-#endif
-
-#ifndef strerror_r
-#define strerror_r(a, b, c) strerror_s(b, c, a)
-#endif
-
-#ifndef strdup
-/* strdup is deprecated in Microsoft libc and _strdup is preferred */
-#define strdup(str) _strdup(str)
-#endif
-
-#ifndef strtok_r
-#define strtok_r(str, delim, saveptr) strtok_s(str, delim, saveptr)
-#endif
-
-#ifndef index
-#define index(a, b)     strchr(a, b)
-#endif
-
-#ifndef rindex
-#define rindex(a, b)    strrchr(a, b)
-#endif
-
-#ifndef strncasecmp
-#define strncasecmp(s1, s2, count)        _strnicmp(s1, s2, count)
-#endif
-
-#ifndef close
-#define close _close
-#endif
-
-#ifndef unlink
-#define unlink _unlink
-#endif
-
 /* cpu_set macros implementation */
 #define RTE_CPU_AND(dst, src1, src2) CPU_AND(dst, src1, src2)
 #define RTE_CPU_OR(dst, src1, src2) CPU_OR(dst, src1, src2)
 #define RTE_CPU_FILL(set) CPU_FILL(set)
 #define RTE_CPU_NOT(dst, src) CPU_NOT(dst, src)
 
-/* as in <windows.h> */
+/* This is an exception without "rte_" prefix, because Windows does have
+ * ssize_t, but it's defined in <windows.h> which we avoid to expose.
+ * If ssize_t is defined in user code, it necessarily has the same type.
+ */
 typedef long long ssize_t;
 
-#ifndef RTE_TOOLCHAIN_GCC
-
-static inline int
-asprintf(char **buffer, const char *format, ...)
-{
-	int size, ret;
-	va_list arg;
-
-	va_start(arg, format);
-	size = vsnprintf(NULL, 0, format, arg);
-	va_end(arg);
-	if (size < 0)
-		return -1;
-	size++;
-
-	*buffer = (char *)malloc(size);
-	if (*buffer == NULL)
-		return -1;
-
-	va_start(arg, format);
-	ret = vsnprintf(*buffer, size, format, arg);
-	va_end(arg);
-	if (ret != size - 1) {
-		free(*buffer);
-		return -1;
-	}
-	return ret;
-}
-
-static inline const char *
-eal_strerror(int code)
-{
-	static char buffer[128];
-
-	strerror_s(buffer, sizeof(buffer), code);
-	return buffer;
-}
-
-#ifndef strerror
-#define strerror eal_strerror
-#endif
-
-#endif /* RTE_TOOLCHAIN_GCC */
-
 #ifdef __cplusplus
 }
 #endif
diff --git a/lib/librte_eal/windows/include/rte_os_internal.h b/lib/librte_eal/windows/include/rte_os_internal.h
new file mode 100644
index 0000000000..84e39eb2ae
--- /dev/null
+++ b/lib/librte_eal/windows/include/rte_os_internal.h
@@ -0,0 +1,28 @@ 
+/* SPDX-License-Identifier: BSD-3-Clause */
+
+#ifndef _RTE_OS_INTERNAL_H_
+#define _RTE_OS_INTERNAL_H_
+
+#include <rte_os.h>
+
+/**
+ * @file
+ * @internal
+ * Provides semi-standard OS facilities by convenient names.
+ */
+
+#ifndef PATH_MAX
+#define PATH_MAX _MAX_PATH
+#endif
+
+#define strdup(str) _strdup(str)
+#define strtok_r(str, delim, saveptr) strtok_s(str, delim, saveptr)
+#define strncasecmp(s1, s2, count) _strnicmp(s1, s2, count)
+
+#define open(path, flags, ...) _open(path, flags, ##__VA_ARGS__)
+#define read(fd, buf, n) _read(fd, buf, n)
+#define write(fd, buf, n) _write(fd, buf, n)
+#define close(fd) _close(fd)
+#define unlink(path) _unlink(path)
+
+#endif /* _RTE_OS_INTERNAL_H_ */
diff --git a/lib/librte_ethdev/ethdev_private.h b/lib/librte_ethdev/ethdev_private.h
index 905a45c337..bd601072fa 100644
--- a/lib/librte_ethdev/ethdev_private.h
+++ b/lib/librte_ethdev/ethdev_private.h
@@ -5,6 +5,8 @@ 
 #ifndef _ETH_PRIVATE_H_
 #define _ETH_PRIVATE_H_
 
+#include <rte_os_internal.h>
+
 #include "rte_ethdev.h"
 
 #ifdef __cplusplus
diff --git a/lib/librte_kvargs/rte_kvargs.c b/lib/librte_kvargs/rte_kvargs.c
index 285081c86c..f5221a2f71 100644
--- a/lib/librte_kvargs/rte_kvargs.c
+++ b/lib/librte_kvargs/rte_kvargs.c
@@ -6,6 +6,7 @@ 
 #include <string.h>
 #include <stdlib.h>
 
+#include <rte_os_internal.h>
 #include <rte_string_fns.h>
 
 #include "rte_kvargs.h"