Module Name: src
Committed By: christos
Date: Sun Nov 20 23:01:19 UTC 2011
Modified Files:
src/sys/kern: subr_prf.c
Log Message:
snprintf/vsnprintf can accept NULL/0 buffers and work properly as expected.
Before they used to return incorrect length on short buffers. Remove unused
error path.
To generate a diff of this commit:
cvs rdiff -u -r1.143 -r1.144 src/sys/kern/subr_prf.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/kern/subr_prf.c
diff -u src/sys/kern/subr_prf.c:1.143 src/sys/kern/subr_prf.c:1.144
--- src/sys/kern/subr_prf.c:1.143 Thu Sep 29 16:52:39 2011
+++ src/sys/kern/subr_prf.c Sun Nov 20 18:01:18 2011
@@ -1,4 +1,4 @@
-/* $NetBSD: subr_prf.c,v 1.143 2011/09/29 20:52:39 christos Exp $ */
+/* $NetBSD: subr_prf.c,v 1.144 2011/11/20 23:01:18 christos Exp $ */
/*-
* Copyright (c) 1986, 1988, 1991, 1993
@@ -37,7 +37,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: subr_prf.c,v 1.143 2011/09/29 20:52:39 christos Exp $");
+__KERNEL_RCSID(0, "$NetBSD: subr_prf.c,v 1.144 2011/11/20 23:01:18 christos Exp $");
#include "opt_ddb.h"
#include "opt_ipkdb.h"
@@ -1024,8 +1024,9 @@ sprintf(char *bf, const char *fmt, ...)
va_start(ap, fmt);
retval = kprintf(fmt, TOBUFONLY, NULL, bf, ap);
va_end(ap);
- *(bf + retval) = 0; /* null terminate */
- return(retval);
+ if (bf)
+ bf[retval] = '\0'; /* nul terminate */
+ return retval;
}
/*
@@ -1038,8 +1039,9 @@ vsprintf(char *bf, const char *fmt, va_l
int retval;
retval = kprintf(fmt, TOBUFONLY, NULL, bf, ap);
- *(bf + retval) = 0; /* null terminate */
- return (retval);
+ if (bf)
+ bf[retval] = '\0'; /* nul terminate */
+ return retval;
}
/*
@@ -1052,14 +1054,13 @@ snprintf(char *bf, size_t size, const ch
va_list ap;
char *p;
- if (size < 1)
- return (-1);
- p = bf + size - 1;
+ p = bf + size;
va_start(ap, fmt);
retval = kprintf(fmt, TOBUFONLY, &p, bf, ap);
va_end(ap);
- *(p) = 0; /* null terminate */
- return(retval);
+ if (bf && p < bf + size)
+ *p = '\0'; /* nul terminate */
+ return retval;
}
/*
@@ -1071,12 +1072,11 @@ vsnprintf(char *bf, size_t size, const c
int retval;
char *p;
- if (size < 1)
- return (-1);
- p = bf + size - 1;
+ p = bf + size;
retval = kprintf(fmt, TOBUFONLY, &p, bf, ap);
- *(p) = 0; /* null terminate */
- return(retval);
+ if (bf && p < bf + size)
+ *p = '\0'; /* nul terminate */
+ return retval;
}
/*
@@ -1134,13 +1134,10 @@ vsnprintf(char *bf, size_t size, const c
#define KPRINTF_PUTCHAR(C) { \
if (oflags == TOBUFONLY) { \
- if ((vp != NULL) && (sbuf == tailp)) { \
- ret += 1; /* indicate error */ \
- goto overflow; \
- } \
- *sbuf++ = (C); \
+ if ((vp == NULL) || (sbuf < tailp)) \
+ *sbuf++ = (C); \
} else { \
- putchar((C), oflags, (struct tty *)vp); \
+ putchar((C), oflags, vp); \
} \
}
@@ -1181,9 +1178,10 @@ kprintf(const char *fmt0, int oflags, vo
char bf[KPRINTF_BUFSIZE]; /* space for %c, %[diouxX] */
char *tailp; /* tail pointer for snprintf */
- tailp = NULL; /* XXX: shutup gcc */
if (oflags == TOBUFONLY && (vp != NULL))
tailp = *(char **)vp;
+ else
+ tailp = NULL;
cp = NULL; /* XXX: shutup gcc */
size = 0; /* XXX: shutup gcc */
@@ -1526,7 +1524,5 @@ done:
if ((oflags == TOBUFONLY) && (vp != NULL))
*(char **)vp = sbuf;
(*v_flush)();
-overflow:
- return (ret);
- /* NOTREACHED */
+ return ret;
}
