diff options
Diffstat (limited to 'libpipe/pq.h')
| -rw-r--r-- | libpipe/pq.h | 148 |
1 files changed, 85 insertions, 63 deletions
diff --git a/libpipe/pq.h b/libpipe/pq.h index 3a26aa80..2ff8c326 100644 --- a/libpipe/pq.h +++ b/libpipe/pq.h @@ -1,6 +1,6 @@ /* Packet queues - Copyright (C) 1995, 1996, 2006 Free Software Foundation, Inc. + Copyright (C) 1995, 1996, 2006, 2009 Free Software Foundation, Inc. Written by Miles Bader <miles@gnu.ai.mit.edu> @@ -25,11 +25,6 @@ #include <stddef.h> /* for size_t */ #include <string.h> #include <mach/mach.h> - -#ifndef PQ_EI -#define PQ_EI extern inline -#endif - struct packet { @@ -71,11 +66,7 @@ error_t packet_set_ports (struct packet *packet, void packet_dealloc_ports (struct packet *packet); /* Returns the number of bytes of data in PACKET. */ -PQ_EI size_t -packet_readable (struct packet *packet) -{ - return packet->buf_end - packet->buf_start; -} +size_t packet_readable (struct packet *packet); /* Append the bytes in DATA, of length DATA_LEN, to what's already in PACKET, and return the amount appended in AMOUNT if that's not the null pointer. */ @@ -96,12 +87,7 @@ error_t packet_read_ports (struct packet *packet, /* Return the source addressd in PACKET in SOURCE, deallocating it from PACKET. */ -PQ_EI void -packet_read_source (struct packet *packet, void **source) -{ - *source = packet->source; - packet->source = 0; -} +void packet_read_source (struct packet *packet, void **source); /* The packet size above which we start to do things differently to avoid copying around data. */ @@ -127,7 +113,82 @@ error_t packet_realloc (struct packet *packet, size_t new_len); /* Try to make space in PACKET for AMOUNT more bytes without growing the buffer, returning true if we could do it. */ -PQ_EI int +int packet_fit (struct packet *packet, size_t amount); + +/* Make sure that PACKET has room for at least AMOUNT more bytes, or return + the reason why not. */ +error_t packet_ensure (struct packet *packet, size_t amount); + +/* Make sure that PACKET has room for at least AMOUNT more bytes, *only* if + it can be done efficiently, e.g., the packet can be grown in place, rather + than moving the contents (or there is little enough data so that copying + it is OK). True is returned if room was made, false otherwise. */ +int packet_ensure_efficiently (struct packet *packet, size_t amount); + +struct pq +{ + struct packet *head, *tail; /* Packet queue */ + struct packet *free; /* Free packets */ +}; + +/* Pushes a new packet of type TYPE and source SOURCE, and returns it, or + NULL if there was an allocation error. SOURCE is returned to readers of + the packet, or deallocated by calling pipe_dealloc_addr. */ +struct packet *pq_queue (struct pq *pq, unsigned type, void *source); + +/* Returns the tail of the packet queue PQ, which may mean pushing a new + packet if TYPE and SOURCE do not match the current tail, or this is the + first packet. */ +struct packet *pq_tail (struct pq *pq, unsigned type, void *source); + +/* Remove the first packet (if any) in PQ, deallocating any resources it + holds. True is returned if a packet was found, false otherwise. */ +int pq_dequeue (struct pq *pq); + +/* Returns the next available packet in PQ, without removing it from the + queue, or NULL if there is none, or the next packet isn't appropiate. + A packet is inappropiate if SOURCE is non-NULL its source field doesn't + match it, or TYPE is non-NULL and the packet's type field doesn't match + it. */ +struct packet *pq_head (struct pq *pq, unsigned type, void *source); + +/* The same as pq_head, but first discards the head of the queue. */ +struct packet *pq_next (struct pq *pq, unsigned type, void *source); + +/* Dequeues all packets in PQ. */ +void pq_drain (struct pq *pq); + +/* Create a new packet queue, returning it in PQ. The only possible error is + ENOMEM. */ +error_t pq_create (struct pq **pq); + +/* Frees PQ and any resources it holds, including deallocating any ports in + packets left in the queue. */ +void pq_free (struct pq *pq); + +/* Inlining optimizations. */ + +#include <features.h> + +#ifdef __USE_EXTERN_INLINES +# ifndef PQ_H_EXTERN_INLINE +# define PQ_H_EXTERN_INLINE __extern_inline +# endif + +PQ_H_EXTERN_INLINE size_t +packet_readable (struct packet *packet) +{ + return packet->buf_end - packet->buf_start; +} + +PQ_H_EXTERN_INLINE void +packet_read_source (struct packet *packet, void **source) +{ + *source = packet->source; + packet->source = 0; +} + +PQ_H_EXTERN_INLINE int packet_fit (struct packet *packet, size_t amount) { char *buf = packet->buf, *end = packet->buf_end; @@ -157,9 +218,7 @@ packet_fit (struct packet *packet, size_t amount) return 1; } -/* Make sure that PACKET has room for at least AMOUNT more bytes, or return - the reason why not. */ -PQ_EI error_t +PQ_H_EXTERN_INLINE error_t packet_ensure (struct packet *packet, size_t amount) { if (! packet_fit (packet, amount)) @@ -172,11 +231,7 @@ packet_ensure (struct packet *packet, size_t amount) return 0; } -/* Make sure that PACKET has room for at least AMOUNT more bytes, *only* if - it can be done efficiently, e.g., the packet can be grown in place, rather - than moving the contents (or there is little enough data so that copying - it is OK). True is returned if room was made, false otherwise. */ -PQ_EI int +PQ_H_EXTERN_INLINE int packet_ensure_efficiently (struct packet *packet, size_t amount) { if (! packet_fit (packet, amount)) @@ -189,22 +244,8 @@ packet_ensure_efficiently (struct packet *packet, size_t amount) } return 0; } - -struct pq -{ - struct packet *head, *tail; /* Packet queue */ - struct packet *free; /* Free packets */ -}; -/* Pushes a new packet of type TYPE and source SOURCE, and returns it, or - NULL if there was an allocation error. SOURCE is returned to readers of - the packet, or deallocated by calling pipe_dealloc_addr. */ -struct packet *pq_queue (struct pq *pq, unsigned type, void *source); - -/* Returns the tail of the packet queue PQ, which may mean pushing a new - packet if TYPE and SOURCE do not match the current tail, or this is the - first packet. */ -PQ_EI struct packet * +PQ_H_EXTERN_INLINE struct packet * pq_tail (struct pq *pq, unsigned type, void *source) { struct packet *tail = pq->tail; @@ -214,16 +255,7 @@ pq_tail (struct pq *pq, unsigned type, void *source) return tail; } -/* Remove the first packet (if any) in PQ, deallocating any resources it - holds. True is returned if a packet was found, false otherwise. */ -int pq_dequeue (struct pq *pq); - -/* Returns the next available packet in PQ, without removing it from the - queue, or NULL if there is none, or the next packet isn't appropiate. - A packet is inappropiate if SOURCE is non-NULL its source field doesn't - match it, or TYPE is non-NULL and the packet's type field doesn't match - it. */ -PQ_EI struct packet * +PQ_H_EXTERN_INLINE struct packet * pq_head (struct pq *pq, unsigned type, void *source) { struct packet *head = pq->head; @@ -236,8 +268,7 @@ pq_head (struct pq *pq, unsigned type, void *source) return head; } -/* The same as pq_head, but first discards the head of the queue. */ -PQ_EI struct packet * +PQ_H_EXTERN_INLINE struct packet * pq_next (struct pq *pq, unsigned type, void *source) { if (!pq->head) @@ -246,15 +277,6 @@ pq_next (struct pq *pq, unsigned type, void *source) return pq_head (pq, type, source); } -/* Dequeues all packets in PQ. */ -void pq_drain (struct pq *pq); - -/* Create a new packet queue, returning it in PQ. The only possible error is - ENOMEM. */ -error_t pq_create (struct pq **pq); - -/* Frees PQ and any resources it holds, including deallocating any ports in - packets left in the queue. */ -void pq_free (struct pq *pq); +#endif /* __USE_EXTERN_INLINES */ #endif /* __PQ_H__ */ |