Re: [dpdk-dev] [PATCH] eal: fix broken rte strerror

[Thomas Monjalon <thomas@monjalon.net>]

02/11/2018 09:11, Jerin Jacob:
> errno_autotest testcase were failed since
> commit 5d7b673d5fd6 ("mk: build with _GNU_SOURCE defined by default")
> RTE>>errno_autotest
> rte_strerror: 'Unknown error 11',
> strerror: 'Resource temporarily unavailable'
> Test Failed
> 
> There are two different version of strerror_t() based on
> _GNU_SOURCE definition.
> 
> /* XSI-compliant */
> int strerror_r(int errnum, char *buf, size_t buflen);
> 
> /* GNU-specific */
> char *strerror_r(int errnum, char *buf, size_t buflen);
> 
> Since the GNU-specific version returns char* the exiting "if"
> condition around the strerror_r fails.
> 
> Switching back to XSI-compliant version to allow
> 
> a) Portable strerror_r() usage as musl c library uses
> non GNU speficic version
> https://git.musl-libc.org/cgit/musl/tree/src/string/strerror_r.c
> 
> b) Based on strerror_r(3) man page, it is possible that GNU-specific
> version need not use char *buf to fill error message instead it
> can use the immutable static string from the library and return it.
> 
> note from strerror_r(3) man page:
> 
> The GNU-specific strerror_r() returns a pointer to a string containing
> the error message.  This may be either a pointer to a string that the
> function stores in buf, or a pointer to some (immutable)
> static string (in which case buf is unused).
> 
> Fixes: 5d7b673d5fd6 ("mk: build with _GNU_SOURCE defined by default")
> 
> Signed-off-by: Jerin Jacob <jerin.jacob@caviumnetworks.com>

You may be interested by this patch from Ferruh:
	https://patches.dpdk.org/patch/47622/