diff options
Diffstat (limited to 'lib/qiovec.h')
| -rw-r--r-- | lib/qiovec.h | 174 |
1 files changed, 164 insertions, 10 deletions
diff --git a/lib/qiovec.h b/lib/qiovec.h index 230198f3..0cbf0364 100644 --- a/lib/qiovec.h +++ b/lib/qiovec.h @@ -26,22 +26,54 @@ #include <sys/uio.h> /* iovec stuff */ /*============================================================================== + * Alternative naming for struct iovec and its entries. + */ +struct qiov_item +{ + const char* base ; + size_t len ; +} ; + +typedef struct qiov_item* qiov_item ; +typedef struct qiov_item qiov_item_t[1] ; +typedef struct qiov_item* qiov_vector ; + +union +{ + struct qiov_item q ; + struct iovec s ; +} union_iovec ; + +CONFIRM(sizeof(struct qiov_item) == sizeof(struct iovec)) ; + +CONFIRM(offsetof(struct qiov_item, base) == offsetof(struct iovec, iov_base)) ; +CONFIRM(sizeof (union_iovec.q. base) == sizeof (union_iovec.s.iov_base)) ; +CONFIRM(offsetof(struct qiov_item, len) == offsetof(struct iovec, iov_len)) ; +CONFIRM(sizeof (union_iovec.q. len) == sizeof (union_iovec.s.iov_len)) ; + +/*============================================================================== * Flexible size "struct iovec" * * NB: a completely zero structure is a valid, empty qiovec. */ -typedef struct qiovec* qiovec ; -typedef struct qiovec qiovec_t ; struct qiovec { - struct iovec* vec ; /* the actual iovec array */ + qiov_vector vec ; /* the actual iovec array */ + + uint i_get ; /* next entry to get */ + uint i_put ; /* next entry to put */ + + uint i_alloc ; /* number of entries allocated */ bool writing ; /* started, but not finished */ +} ; - unsigned i_get ; /* next entry to get */ - unsigned i_put ; /* next entry to put */ +typedef struct qiovec* qiovec ; +typedef struct qiovec qiovec_t[1] ; - unsigned i_alloc ; /* number of entries allocated */ +enum +{ + QIOVEC_INIT_ALL_ZEROS = true } ; /*============================================================================== @@ -50,18 +82,39 @@ struct qiovec extern qiovec qiovec_init_new(qiovec qiov) ; extern qiovec qiovec_reset(qiovec qiov, bool free_structure) ; - -#define qiovec_reset_keep(qiov) qiovec_reset(qiov, 0) -#define qiovec_reset_free(qiov) qiovec_reset(qiov, 1) +Inline qiovec qiovec_free(qiovec qiov) ; Inline bool qiovec_empty(qiovec qiov) ; +extern size_t qiovec_length(qiovec qiov) ; extern void qiovec_clear(qiovec qiov) ; -extern void qiovec_push(qiovec qiov, const void* base, size_t len) ; extern int qiovec_write_nb(int fd, qiovec qiov) ; +Inline uint qiovec_count(qiovec qiov) ; +Inline void qiovec_push_this(qiovec qiov, const void* base, size_t len) ; +Inline void qiovec_push(qiovec qiov, qiov_item item) ; +Inline void qiovec_pop(qiovec qiov, qiov_item item) ; +Inline void qiovec_shift(qiovec qiov, qiov_item item) ; +Inline void qiovec_unshift(qiovec qiov, qiov_item item) ; + extern int iovec_write_nb(int fd, struct iovec* p_iov, int n) ; Inline void iovec_set(struct iovec* p_iov, const void* base, size_t len) ; +Private void qiovec_extend(qiovec qiov) ; +Private void qiovec_shuffle(qiovec qiov) ; + +/*------------------------------------------------------------------------------ + * Free given qiovec + * + * It is the caller's responsibility to free anything that the qiovec may + * point to. + * + * Returns: NULL + */ +Inline qiovec qiovec_free(qiovec qiov) +{ + return qiovec_reset(qiov, free_it) ; +} ; + /*------------------------------------------------------------------------------ * Is given qiov empty ? * @@ -75,6 +128,107 @@ qiovec_empty(qiovec qiov) } ; /*------------------------------------------------------------------------------ + * How many entries in the given qiov ? + */ +Inline uint +qiovec_count(qiovec qiov) +{ + return (qiov->i_put - qiov->i_get) ; +} ; + +/*------------------------------------------------------------------------------ + * Push to qiov -- same as qiovec_push, but with item. + * + * Ignores zero length items. + */ +Inline void +qiovec_push_this(qiovec qiov, const void* base, size_t len) +{ + qiov_item_t item ; + + item->base = base ; + item->len = len ; + qiovec_push(qiov, item) ; +} ; + +/*------------------------------------------------------------------------------ + * Push (copy of) item to qiov -- ie append it to the end of the vector. + */ +Inline void +qiovec_push(qiovec qiov, qiov_item item) +{ + if (item->len != 0) + { + if (qiov->i_put >= qiov->i_alloc) + qiovec_extend(qiov) ; + + qiov->vec[qiov->i_put++] = *item ; + } ; +} ; + +/*------------------------------------------------------------------------------ + * Pop last item from qiov -- return empty item if none. + */ +Inline void +qiovec_pop(qiovec qiov, qiov_item item) +{ + if (qiov->i_get < qiov->i_put) + { + *item = qiov->vec[--qiov->i_put] ; + if (qiov->i_get == qiov->i_put) + qiov->i_get = qiov->i_put = 0 ; + } + else + { + assert(qiov->i_get == qiov->i_put) ; + item->base = NULL ; + item->len = 0 ; + + qiov->i_get = qiov->i_put = 0 ; + } ; +} ; + +/*------------------------------------------------------------------------------ + * Shift first item off qiov -- return empty item if none. + */ +Inline void +qiovec_shift(qiovec qiov, qiov_item item) +{ + if (qiov->i_get < qiov->i_put) + { + *item = qiov->vec[qiov->i_get++] ; + if (qiov->i_get == qiov->i_put) + qiov->i_get = qiov->i_put = 0 ; + } + else + { + assert(qiov->i_get == qiov->i_put) ; + item->base = NULL ; + item->len = 0 ; + + qiov->i_get = qiov->i_put = 0 ; + } ; +} ; + +/*------------------------------------------------------------------------------ + * Unshift item onto qiov -- ie prepend it to the start of the vector. + */ +Inline void +qiovec_unshift(qiovec qiov, qiov_item item) +{ + if (qiov->i_get == 0) + { + if (qiov->i_put == 0) + return qiovec_push(qiov, item) ; + + qiovec_shuffle(qiov) ; + } ; + + if (item->len != 0) + qiov->vec[--qiov->i_get] = *item ; +} ; + +/*------------------------------------------------------------------------------ * Set a given struct iovec * * Gets around the fact that the standard structure does not have a const |