diff options
Diffstat (limited to 'common/membuf.c')
| -rw-r--r-- | common/membuf.c | 45 |
1 files changed, 44 insertions, 1 deletions
diff --git a/common/membuf.c b/common/membuf.c index f9f82d357..8648044a7 100644 --- a/common/membuf.c +++ b/common/membuf.c @@ -1,5 +1,5 @@ /* membuf.c - A simple implementation of a dynamic buffer. - * Copyright (C) 2001, 2003, 2009 Free Software Foundation, Inc. + * Copyright (C) 2001, 2003, 2009, 2011 Free Software Foundation, Inc. * * This file is part of GnuPG. * @@ -56,6 +56,26 @@ init_membuf_secure (membuf_t *mb, int initiallen) } +/* Shift the the content of the membuf MB by AMOUNT bytes. The next + operation will then behave as if AMOUNT bytes had not been put into + the buffer. If AMOUNT is greater than the actual accumulated + bytes, the membuf is basically reset to its initial state. */ +void +clear_membuf (membuf_t *mb, size_t amount) +{ + /* No need to clear if we are already out of core. */ + if (mb->out_of_core) + return; + if (amount >= mb->len) + mb->len = 0; + else + { + mb->len -= amount; + memmove (mb->buf, mb->buf+amount, mb->len); + } +} + + void put_membuf (membuf_t *mb, const void *buf, size_t len) { @@ -116,3 +136,26 @@ get_membuf (membuf_t *mb, size_t *len) mb->out_of_core = ENOMEM; /* hack to make sure it won't get reused. */ return p; } + + +/* Peek at the membuf MB. On success a pointer to the buffer is + returned which is valid until the next operation on MB. If LEN is + not NULL the current LEN of the buffer is stored there. On error + NULL is returned and ERRNO is set. */ +const void * +peek_membuf (membuf_t *mb, size_t *len) +{ + const char *p; + + if (mb->out_of_core) + { + gpg_err_set_errno (mb->out_of_core); + return NULL; + } + + p = mb->buf; + if (len) + *len = mb->len; + return p; +} + |