string: Simplify strerror_r

Use snprintf instead of mempcpy plus itoa_word and remove unused
definitions.  There is no potential for infinite recursion because
snprintf only use strerror_r for the %m specifier.

Checked on x86-64-linux-gnu, i686-linux-gnu, powerpc64le-linux-gnu,
and s390x-linux-gnu.

Tested-by: Carlos O'Donell <carlos@redhat.com>
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
This commit is contained in:
Adhemerval Zanella 2020-05-14 18:14:43 -03:00
parent 725eeb4af1
commit 08d2024b41
2 changed files with 7 additions and 101 deletions

View File

@ -15,22 +15,10 @@
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
#include <string.h>
#include <libintl.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/param.h>
#include <_itoa.h>
/* It is critical here that we always use the `dcgettext' function for
the message translation. Since <libintl.h> only defines the macro
`dgettext' to use `dcgettext' for optimizing programs this is not
always guaranteed. */
#ifndef dgettext
# include <locale.h> /* We need LC_MESSAGES. */
# define dgettext(domainname, msgid) dcgettext (domainname, msgid, LC_MESSAGES)
#endif
/* Return a string describing the errno code in ERRNUM. */
char *
@ -39,32 +27,7 @@ __strerror_r (int errnum, char *buf, size_t buflen)
char *err = (char *) __get_errlist (errnum);
if (__glibc_unlikely (err == NULL))
{
/* Buffer we use to print the number in. For a maximum size for
`int' of 8 bytes we never need more than 20 digits. */
char numbuf[21];
const char *unk = _("Unknown error ");
size_t unklen = strlen (unk);
char *p, *q;
bool negative = errnum < 0;
numbuf[20] = '\0';
p = _itoa_word (abs (errnum), &numbuf[20], 10, 0);
/* Now construct the result while taking care for the destination
buffer size. */
q = __mempcpy (buf, unk, MIN (unklen, buflen));
if (negative && unklen < buflen)
{
*q++ = '-';
++unklen;
}
if (unklen < buflen)
memcpy (q, p, MIN ((size_t) (&numbuf[21] - p), buflen - unklen));
/* Terminate the string in any case. */
if (buflen > 0)
buf[buflen - 1] = '\0';
__snprintf (buf, buflen, "%s%d", _("Unknown error "), errnum);
return buf;
}

View File

@ -15,22 +15,12 @@
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
#include <string.h>
#include <libintl.h>
#include <stdio.h>
#include <string.h>
#include <mach/error.h>
#include <errorlib.h>
#include <sys/param.h>
#include <_itoa.h>
/* It is critical here that we always use the `dcgettext' function for
the message translation. Since <libintl.h> only defines the macro
`dgettext' to use `dcgettext' for optimizing programs this is not
always guaranteed. */
#ifndef dgettext
# include <locale.h> /* We need LC_MESSAGES. */
# define dgettext(domainname, msgid) dcgettext (domainname, msgid, LC_MESSAGES)
#endif
/* Return a string describing the errno code in ERRNUM. */
char *
@ -50,26 +40,8 @@ __strerror_r (int errnum, char *buf, size_t buflen)
if (system > err_max_system || ! __mach_error_systems[system].bad_sub)
{
/* Buffer we use to print the number in. For a maximum size for
`int' of 8 bytes we never need more than 20 digits. */
char numbuf[21];
const char *unk = _("Error in unknown error system: ");
const size_t unklen = strlen (unk);
char *p, *q;
numbuf[20] = '\0';
p = _itoa_word (errnum, &numbuf[20], 16, 1);
/* Now construct the result while taking care for the destination
buffer size. */
q = __mempcpy (buf, unk, MIN (unklen, buflen));
if (unklen < buflen)
memcpy (q, p, MIN (&numbuf[21] - p, buflen - unklen));
/* Terminate the string in any case. */
if (buflen > 0)
buf[buflen - 1] = '\0';
__snprintf (buf, buflen, "%s: %d", _("Error in unknown error system: "),
errnum);
return buf;
}
@ -80,37 +52,8 @@ __strerror_r (int errnum, char *buf, size_t buflen)
if (code >= es->subsystem[sub].max_code)
{
/* Buffer we use to print the number in. For a maximum size for
`int' of 8 bytes we never need more than 20 digits. */
char numbuf[21];
const char *unk = _("Unknown error ");
const size_t unklen = strlen (unk);
char *p, *q;
size_t len = strlen (es->subsystem[sub].subsys_name);
numbuf[20] = '\0';
p = _itoa_word (errnum, &numbuf[20], 10, 0);
/* Now construct the result while taking care for the destination
buffer size. */
q = __mempcpy (buf, unk, MIN (unklen, buflen));
if (unklen < buflen)
{
q = __mempcpy (q, es->subsystem[sub].subsys_name,
MIN (len, buflen - unklen));
if (unklen + len < buflen)
{
*q++ = ' ';
if (unklen + len + 1 < buflen)
memcpy (q, p,
MIN (&numbuf[21] - p, buflen - unklen - len - 1));
}
}
/* Terminate the string in any case. */
if (buflen > 0)
buf[buflen - 1] = '\0';
__snprintf (buf, buflen, "%s%s %d", _("Unknown error "),
es->subsystem[sub].subsys_name, errnum);
return buf;
}