From c6218dbae579de0cd20f5a7f1e9877673e28225d Mon Sep 17 00:00:00 2001 From: Eric Andersen Date: Wed, 20 Dec 2000 22:52:58 +0000 Subject: A number of updates from Manuel Novoa III. Things look good... --- libc/string/strerror.c | 61 +++++++++++++++++++++++++++++++++++++++++--------- 1 file changed, 50 insertions(+), 11 deletions(-) (limited to 'libc/string/strerror.c') diff --git a/libc/string/strerror.c b/libc/string/strerror.c index 91565965f..3aa8b57e2 100644 --- a/libc/string/strerror.c +++ b/libc/string/strerror.c @@ -16,31 +16,70 @@ License along with the GNU C Library; see the file COPYING.LIB. If not, write to the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ +/* + * Manuel Novoa III Dec 2000 + * + * Converted to use my new (un)signed long (long) to string routines, which + * are smaller than the previous functions and don't require static buffers. + * Removed dependence on strcat in the process. + * + * Also appended a test routine ( -DSTRERROR_TEST ) to allow a quick check + * on the buffer length when the sys_errorlist is modified. + */ + #include #include #include +#include + +#if (INT_MAX >> 31) +/* We're set up for 32 bit ints */ +#error need to check size allocation for static buffer 'retbuf' +#endif -extern char *itoa(int); +extern char *__ltostr(char *buf, long uval, int base, int uppercase); + +static char retbuf[33]; /* 33 is sufficient for 32 bit ints */ +static const char unknown_error[] = "Unknown Error: errno"; /* = */ /* Return a string descibing the errno code in ERRNUM. The storage is good only until the next call to strerror. Writing to the storage causes undefined behavior. */ char *strerror(int err) { - static char retbuf[80]; + char *pos; - if (sys_nerr) { - if (err < 0 || err >= sys_nerr) - goto unknown; + if ((err >= 0) && (err < sys_nerr)) { strcpy(retbuf, sys_errlist[err]); return retbuf; } - if (err <= 0) - goto unknown; + /* unknown error */ + pos = __ltostr(retbuf + sizeof(retbuf) + 1, err, 10, 0) + - sizeof(unknown_error); /* leave space for the '=' */ + strcpy(pos, unknown_error); + *(pos + sizeof(unknown_error) - 1) = '='; + return pos; +} + +#if STRERROR_TEST +/* quick way to check for sufficient buffer length */ +#include +#include +int main(void) +{ + int max = 0; + int i, j; + char *p; + for ( i=0 ; i < sys_nerr ; i++ ) { + j = strlen(sys_errlist[i])+1; + if (j > max) max = j; + } + printf("max len = %i\n", j); - unknown: - strcpy(retbuf, "Unknown Error: errno="); - strcat(retbuf, (char *) itoa(err)); - return retbuf; + p = strerror(INT_MIN); + printf("<%s> %d\n", p, strlen(p)+1); + printf("current buffer length is %d\n", sizeof(retbuf)); + return EXIT_SUCCESS; } +#endif -- cgit v1.2.3