Thread-safe error handling

In order for the interface to become more thread safe, the error
handling was revised to no longer depend on a static errno and
error string buffer.

This patch converts all error paths to return a libnl specific
error code which can be translated to a error message using
nl_geterror(int error). The functions nl_error() and
nl_get_errno() are therefore obsolete.

This change required various sets of function prototypes to be
changed in order to return an error code, the most prominent
are:

    struct nl_cache *foo_alloc_cache(...);
changed to:
    int foo_alloc_cache(..., struct nl_cache **);

    struct nl_msg *foo_build_request(...);
changed to:
    int foo_build_request(..., struct nl_msg **);

    struct foo *foo_parse(...);
changed to:
    int foo_parse(..., struct foo **);

This pretty much only leaves trivial allocation functions to
still return a pointer object which can still return NULL to
signal out of memory.

This change is a serious API and ABI breaker, sorry!

1 files changed, 1 insertions, 5 deletions

diff --git a/include/netlink/utils.h b/include/netlink/utils.h
index 207e8ec..2b6bcb7 100644
--- a/include/netlink/utils.h
+++ b/include/netlink/utils.h
@@ -6,7 +6,7 @@
  *	License as published by the Free Software Foundation version 2.1
  *	of the License.
  *
- * Copyright (c) 2003-2006 Thomas Graf <tgraf@suug.ch>
+ * Copyright (c) 2003-2008 Thomas Graf <tgraf@suug.ch>
  */
 
 #ifndef NETLINK_UTILS_H_
@@ -38,10 +38,6 @@ extern "C" {
 
 /** @} */
 
-extern char *	nl_geterror(void);
-extern int	nl_get_errno(void);
-extern void	nl_perror(const char *);
-
 /* unit pretty-printing */
 extern double	nl_cancel_down_bytes(unsigned long long, char **);
 extern double	nl_cancel_down_bits(unsigned long long, char **);