On Fri, Sep 21, 2018 at 03:20:37PM -0400, Steven Rostedt wrote: > From: "Steven Rostedt (VMware)" <[email protected]> > > While working on having PowerTop use libtracevent as a shared object > library, Tzvetomir hit "str_error_r not defined". This was added by commit > c3cec9e68f12d ("tools lib traceevent: Use str_error_r()") because > strerror_r() has two definitions, where one is GNU specific, and the other > is XSI complient. The strerror_r() is in a wrapper str_error_r() to keep the > code from having to worry about which compiler is being used. > > The problem is that str_error_r() is external to libtraceevent, and not part > of the library. If it is used as a shared object then the tools using it > will need to define that function. I do not want that function defined in > libtraceevent itself, as it is out of scope for that library. > > As there's only a single instance of this call, I replaced it with an open > coded algorithm that just uses strerror() and strncpy() to place the error > message in the given buffer. We don't need to worry about the errors that > strerror_r() returns. If the buffer isn't big enough, we simply truncate it. > > Reported-by: Tzvetomir Stoyanov <[email protected]> > Signed-off-by: Steven Rostedt (VMware) <[email protected]>
Acked-by: Jiri Olsa <[email protected]> thanks, jirka > --- > > Changes from v1: > > - Account for buflen being zero (do nothing). > > tools/lib/traceevent/event-parse.c | 8 ++++++-- > 1 file changed, 6 insertions(+), 2 deletions(-) > > diff --git a/tools/lib/traceevent/event-parse.c > b/tools/lib/traceevent/event-parse.c > index 7980fc6c3bac..ba7570646d2c 100644 > --- a/tools/lib/traceevent/event-parse.c > +++ b/tools/lib/traceevent/event-parse.c > @@ -18,7 +18,6 @@ > #include <errno.h> > #include <stdint.h> > #include <limits.h> > -#include <linux/string.h> > #include <linux/time64.h> > > #include <netinet/in.h> > @@ -6215,7 +6214,12 @@ int tep_strerror(struct tep_handle *pevent > __maybe_unused, > const char *msg; > > if (errnum >= 0) { > - str_error_r(errnum, buf, buflen); > + const char *error_str = strerror(errnum); > + > + if (buflen > 0) { > + strncpy(buf, error_str, buflen); > + buf[buflen - 1] = 0; > + } > return 0; > } > > -- > 2.13.6 >
