acl/lib_acl/include/stdlib/acl_vbuf.h

77 lines
2.6 KiB
C

#ifndef ACL_VBUF_INCLUDE_H
#define ACL_VBUF_INCLUDE_H
#ifdef __cplusplus
extern "C" {
#endif
#include "acl_define.h"
typedef struct ACL_VBUF ACL_VBUF;
typedef int (*ACL_VBUF_GET_READY_FN) (ACL_VBUF *);
typedef int (*ACL_VBUF_PUT_READY_FN) (ACL_VBUF *);
typedef int (*ACL_VBUF_SPACE_FN) (ACL_VBUF *, int);
struct ACL_VBUF {
int flags; /* status, see below */
unsigned char *data; /* variable-length buffer */
int len; /* buffer length */
int cnt; /* bytes left to read/write */
unsigned char *ptr; /* read/write position */
ACL_VBUF_GET_READY_FN get_ready; /* read buffer empty action */
ACL_VBUF_PUT_READY_FN put_ready; /* write buffer full action */
ACL_VBUF_SPACE_FN space; /* request for buffer space */
void *ctx;
};
/*
* Typically, an application will embed a VBUF structure into a larger
* structure that also contains application-specific members. This approach
* gives us the best of both worlds. The application can still use the
* generic VBUF primitives for reading and writing VBUFs. The macro below
* transforms a pointer from VBUF structure to the structure that contains
* it.
*/
#define ACL_VBUF_TO_APPL(vbuf_ptr,app_type,vbuf_member) \
((app_type *) (((char *) (vbuf_ptr)) - offsetof(app_type,vbuf_member)))
/*
* Buffer status management.
*/
#define ACL_VBUF_FLAG_ERR (1<<0) /* some I/O error */
#define ACL_VBUF_FLAG_EOF (1<<1) /* end of data */
#define ACL_VBUF_FLAG_TIMEOUT (1<<2) /* timeout error */
#define ACL_VBUF_FLAG_BAD (ACL_VBUF_FLAG_ERR | ACL_VBUF_FLAG_EOF | ACL_VBUF_FLAG_TIMEOUT)
#define ACL_VBUF_FLAG_FIXED (1<<3) /* fixed-size buffer */
#define acl_vbuf_error(v) ((v)->flags & ACL_VBUF_FLAG_ERR)
#define acl_vbuf_eof(v) ((v)->flags & ACL_VBUF_FLAG_EOF)
#define acl_vbuf_timeout(v) ((v)->flags & ACL_VBUF_FLAG_TIMEOUT)
#define acl_vbuf_clearerr(v) ((v)->flags &= ~ACL_VBUF_FLAG_BAD)
/*
* Buffer I/O-like operations and results.
*/
#define ACL_VBUF_GET(v) ((v)->cnt < 0 ? ++(v)->cnt, \
(int) *(v)->ptr++ : acl_vbuf_get(v))
#define ACL_VBUF_PUT(v,c) ((v)->cnt > 0 ? --(v)->cnt, \
(int) (*(v)->ptr++ = (c)) : acl_vbuf_put((v),(c)))
#define ACL_VBUF_SPACE(v,n) ((v)->space((v),(n)))
#define ACL_VBUF_CHARAT(v, offset) ((int) (v).data[offset])
#define ACL_VBUF_EOF (-1) /* no more space or data */
ACL_API int acl_vbuf_get(ACL_VBUF *);
ACL_API int acl_vbuf_put(ACL_VBUF *, int);
ACL_API int acl_vbuf_unget(ACL_VBUF *, int);
ACL_API int acl_vbuf_read(ACL_VBUF *, char *, int);
ACL_API int acl_vbuf_write(ACL_VBUF *, const char *, int);
#ifdef __cplusplus
}
#endif
#endif