From 98b0c9dfba7e5c413668f833934dace92372bbe3 Mon Sep 17 00:00:00 2001 From: Paul Ackersviller Date: Tue, 4 Dec 2007 01:24:20 +0000 Subject: Slight tweak of pws's 24148: attempt to use strerror_r() to make error messages in signal handle safer. --- Src/utils.c | 38 ++++++++++++++++++++++++++++++++++++-- 1 file changed, 36 insertions(+), 2 deletions(-) diff --git a/Src/utils.c b/Src/utils.c index e1459cb2b..a71eddf16 100644 --- a/Src/utils.c +++ b/Src/utils.c @@ -129,6 +129,13 @@ zz_plural_z_alpha(void) void zerrmsg(const char *fmt, const char *str, int num) { +#ifdef HAVE_STRERROR_R +#define ERRBUFSIZE (80) + int olderrno; + char errbuf[ERRBUFSIZE]; +#endif + char *errmsg; + if ((unset(SHINSTDIN) || locallevel) && lineno) fprintf(stderr, "%ld: ", (long)lineno); else @@ -166,12 +173,39 @@ zerrmsg(const char *fmt, const char *str, int num) errflag = 1; return; } +#ifdef HAVE_STRERROR_R + /* + * There are two incompatible strerror_r()s floating round. + * The GNU extension refuses to copy the message into the + * buffer if it can return a constant string. To suppress it + * we need to define _XOPEN_SOURCE to 600. I don't dare do + * this because we're already depending on _GNU_SOURCE. So + * try to handle both by looking for errno being set (for the + * standard version failing) or errbuf being left untouched + * (for the GNU version). One presumes that if strerror_r() + * didn't copy anything to errbuf, then it's safe to + * call strerror() to get the string. + * + * This is a mess, but it's about a decade and half + * too late to shirk from messes in the source. + */ + olderrno = errno; + errno = 0; + errbuf[0] = '\0'; + strerror_r(num, errbuf, ERRBUFSIZE); + if (errno || errbuf[0] == '\0') + errmsg = strerror(num); + else + errmsg = errbuf; + errno = olderrno; +#else + errmsg = strerror(num); +#endif /* If the message is not about I/O problems, it looks better * * if we uncapitalize the first letter of the message */ if (num == EIO) - fputs(strerror(num), stderr); + fputs(errmsg, stderr); else { - char *errmsg = strerror(num); fputc(tulower(errmsg[0]), stderr); fputs(errmsg + 1, stderr); } -- cgit 1.4.1