diff options
Diffstat (limited to 'libio')
| -rw-r--r-- | libio/fmemopen.c | 28 |
1 files changed, 15 insertions, 13 deletions
diff --git a/libio/fmemopen.c b/libio/fmemopen.c index 9264b724ee..0f655909e8 100644 --- a/libio/fmemopen.c +++ b/libio/fmemopen.c @@ -50,16 +50,14 @@ fmemopen_read (void *cookie, char *b, size_t s) if (c->pos + s > c->maxpos) { - if ((size_t) c->pos == c->maxpos) - return 0; - s = c->size - c->pos; + s = c->maxpos - c->pos; + if ((size_t) c->pos > c->maxpos) + s = 0; } memcpy (b, &(c->buffer[c->pos]), s); c->pos += s; - if ((size_t) c->pos > c->maxpos) - c->maxpos = c->pos; return s; } @@ -70,28 +68,29 @@ fmemopen_write (void *cookie, const char *b, size_t s) { fmemopen_cookie_t *c = (fmemopen_cookie_t *) cookie;; _IO_off64_t pos = c->append ? c->maxpos : c->pos; - int addnullc; - - addnullc = (s == 0 || b[s - 1] != '\0'); + int addnullc = (s == 0 || b[s - 1] != '\0'); - if (pos + s + addnullc > c->size) + if (pos + s > c->size) { if ((size_t) (c->pos + addnullc) >= c->size) { __set_errno (ENOSPC); return 0; } - s = c->size - pos - addnullc; + s = c->size - pos; } memcpy (&(c->buffer[pos]), b, s); - c->pos += s; + c->pos = pos + s; if ((size_t) c->pos > c->maxpos) { c->maxpos = c->pos; - if (addnullc) + if (c->maxpos < c->size && addnullc) c->buffer[c->maxpos] = '\0'; + /* A null byte is written in a stream open for update iff it fits. */ + else if (c->append == 0 && addnullc != 0) + c->buffer[c->size-1] = '\0'; } return s; @@ -123,7 +122,10 @@ fmemopen_seek (void *cookie, _IO_off64_t *p, int w) } if (np < 0 || (size_t) np > c->size) - return -1; + { + __set_errno (EINVAL); + return -1; + } *p = c->pos = np; |