diff options
| -rw-r--r-- | sys/kern/subr_sbuf.c | 84 |
1 files changed, 42 insertions, 42 deletions
diff --git a/sys/kern/subr_sbuf.c b/sys/kern/subr_sbuf.c index c94657ca97a2..ebde3bee6405 100644 --- a/sys/kern/subr_sbuf.c +++ b/sys/kern/subr_sbuf.c @@ -187,39 +187,6 @@ sbuf_extend(struct sbuf *s, int addlen) } /* - * Initialize the internals of an sbuf. - * If buf is non-NULL, it points to a static or already-allocated string - * big enough to hold at least length characters. - */ -static struct sbuf * -sbuf_newbuf(struct sbuf *s, char *buf, int length, int flags) -{ - - memset(s, 0, sizeof(*s)); - s->s_flags = flags; - s->s_size = length; - s->s_buf = buf; - - if (!SBUF_CANEXTEND(s)) { - KASSERT(s->s_size >= SBUF_MINSIZE, - ("attempt to create an sbuf smaller than %d bytes", - SBUF_MINSIZE)); - } - - if (s->s_buf != NULL) - return (s); - - if (SBUF_CANEXTEND(s)) - s->s_size = sbuf_extendsize(s->s_size); - - s->s_buf = SBMALLOC(s->s_size, SBUF_MALLOCFLAG(s)); - if (s->s_buf == NULL) - return (NULL); - SBUF_SETFLAG(s, SBUF_DYNAMIC); - return (s); -} - -/* * Initialize an sbuf. * If buf is non-NULL, it points to a static or already-allocated string * big enough to hold at least length characters. @@ -232,19 +199,52 @@ sbuf_new(struct sbuf *s, char *buf, int length, int flags) ("attempt to create an sbuf of negative length (%d)", length)); KASSERT((flags & ~SBUF_USRFLAGMSK) == 0, ("%s called with invalid flags", __func__)); + KASSERT((flags & SBUF_AUTOEXTEND) || length >= SBUF_MINSIZE, + ("sbuf buffer %d smaller than minimum %d bytes", length, + SBUF_MINSIZE)); flags &= SBUF_USRFLAGMSK; - if (s != NULL) - return (sbuf_newbuf(s, buf, length, flags)); - s = SBMALLOC(sizeof(*s), (flags & SBUF_NOWAIT) ? M_NOWAIT : M_WAITOK); - if (s == NULL) - return (NULL); - if (sbuf_newbuf(s, buf, length, flags) == NULL) { - SBFREE(s); - return (NULL); + /* + * Allocate 'DYNSTRUCT' sbuf from the heap, if NULL 's' was provided. + */ + if (s == NULL) { + s = SBMALLOC(sizeof(*s), + (flags & SBUF_NOWAIT) ? M_NOWAIT : M_WAITOK); + if (s == NULL) + goto out; + SBUF_SETFLAG(s, SBUF_DYNSTRUCT); + } else { + /* + * DYNSTRUCT SBMALLOC sbufs are allocated with M_ZERO, but + * user-provided sbuf objects must be initialized. + */ + memset(s, 0, sizeof(*s)); + } + + s->s_flags |= flags; + s->s_size = length; + s->s_buf = buf; + + /* + * Allocate DYNAMIC, i.e., heap data buffer backing the sbuf, if no + * buffer was provided. + */ + if (s->s_buf == NULL) { + if (SBUF_CANEXTEND(s)) + s->s_size = sbuf_extendsize(s->s_size); + s->s_buf = SBMALLOC(s->s_size, SBUF_MALLOCFLAG(s)); + if (s->s_buf == NULL) + goto out; + SBUF_SETFLAG(s, SBUF_DYNAMIC); + } + +out: + if (s != NULL && s->s_buf == NULL) { + if (SBUF_ISDYNSTRUCT(s)) + SBFREE(s); + s = NULL; } - SBUF_SETFLAG(s, SBUF_DYNSTRUCT); return (s); } |