freebsd-skq/contrib/libxo/libxo/xo_buf.h
Marcel Moolenaar d1a0d267b7 Upgrade libxo to 0.4.5.
Local changes incorporated by 0.4.5: r284340
Local changes retained: r276260, r282117

Obtained from:	https://github.com/Juniper/libxo
2015-08-24 16:26:20 +00:00

159 lines
3.3 KiB
C

/*
* Copyright (c) 2015, Juniper Networks, Inc.
* All rights reserved.
* This SOFTWARE is licensed under the LICENSE provided in the
* ../Copyright file. By downloading, installing, copying, or otherwise
* using the SOFTWARE, you agree to be bound by the terms of that
* LICENSE.
* Phil Shafer, August 2015
*/
/*
* This file is an _internal_ part of the libxo plumbing, not suitable
* for external use. It is not considered part of the libxo API and
* will not be a stable part of that API. Mine, not your's, dude...
* The real hope is that something like this will become a standard part
* of libc and I can kill this off.
*/
#ifndef XO_BUF_H
#define XO_BUF_H
#define XO_BUFSIZ (8*1024) /* Initial buffer size */
/*
* xo_buffer_t: a memory buffer that can be grown as needed. We
* use them for building format strings and output data.
*/
typedef struct xo_buffer_s {
char *xb_bufp; /* Buffer memory */
char *xb_curp; /* Current insertion point */
unsigned xb_size; /* Size of buffer */
} xo_buffer_t;
/*
* Initialize the contents of an xo_buffer_t.
*/
static inline void
xo_buf_init (xo_buffer_t *xbp)
{
xbp->xb_size = XO_BUFSIZ;
xbp->xb_bufp = xo_realloc(NULL, xbp->xb_size);
xbp->xb_curp = xbp->xb_bufp;
}
/*
* Reset the buffer to empty
*/
static inline void
xo_buf_reset (xo_buffer_t *xbp)
{
xbp->xb_curp = xbp->xb_bufp;
}
/*
* Return the number of bytes left in the buffer
*/
static inline int
xo_buf_left (xo_buffer_t *xbp)
{
return xbp->xb_size - (xbp->xb_curp - xbp->xb_bufp);
}
/*
* See if the buffer to empty
*/
static inline int
xo_buf_is_empty (xo_buffer_t *xbp)
{
return (xbp->xb_curp == xbp->xb_bufp);
}
/*
* Return the current offset
*/
static inline unsigned
xo_buf_offset (xo_buffer_t *xbp)
{
return xbp ? (xbp->xb_curp - xbp->xb_bufp) : 0;
}
static inline char *
xo_buf_data (xo_buffer_t *xbp, unsigned offset)
{
if (xbp == NULL)
return NULL;
return xbp->xb_bufp + offset;
}
static inline char *
xo_buf_cur (xo_buffer_t *xbp)
{
if (xbp == NULL)
return NULL;
return xbp->xb_curp;
}
/*
* Initialize the contents of an xo_buffer_t.
*/
static inline void
xo_buf_cleanup (xo_buffer_t *xbp)
{
if (xbp->xb_bufp)
xo_free(xbp->xb_bufp);
bzero(xbp, sizeof(*xbp));
}
/*
* Does the buffer have room for the given number of bytes of data?
* If not, realloc the buffer to make room. If that fails, we
* return 0 to tell the caller they are in trouble.
*/
static inline int
xo_buf_has_room (xo_buffer_t *xbp, int len)
{
if (xbp->xb_curp + len >= xbp->xb_bufp + xbp->xb_size) {
int sz = xbp->xb_size + XO_BUFSIZ;
char *bp = xo_realloc(xbp->xb_bufp, sz);
if (bp == NULL)
return 0;
xbp->xb_curp = bp + (xbp->xb_curp - xbp->xb_bufp);
xbp->xb_bufp = bp;
xbp->xb_size = sz;
}
return 1;
}
/*
* Append the given string to the given buffer
*/
static inline void
xo_buf_append (xo_buffer_t *xbp, const char *str, int len)
{
if (!xo_buf_has_room(xbp, len))
return;
memcpy(xbp->xb_curp, str, len);
xbp->xb_curp += len;
}
/*
* Append the given NUL-terminated string to the given buffer
*/
static inline void
xo_buf_append_str (xo_buffer_t *xbp, const char *str)
{
int len = strlen(str);
if (!xo_buf_has_room(xbp, len))
return;
memcpy(xbp->xb_curp, str, len);
xbp->xb_curp += len;
}
#endif /* XO_BUF_H */