diff options
Diffstat (limited to 'libpipe/pq.c')
| -rw-r--r-- | libpipe/pq.c | 37 |
1 files changed, 30 insertions, 7 deletions
diff --git a/libpipe/pq.c b/libpipe/pq.c index afdda051..102f3ee3 100644 --- a/libpipe/pq.c +++ b/libpipe/pq.c @@ -349,13 +349,13 @@ packet_write (struct packet *packet, return 0; } -/* Removes up to AMOUNT bytes from the beginning of the data in PACKET, and +/* Remove or peek up to AMOUNT bytes from the beginning of the data in PACKET, and puts it into *DATA, and the amount read into DATA_LEN. If more than the original *DATA_LEN bytes are available, new memory is vm_allocated, and the address and length of this array put into DATA and DATA_LEN. */ -error_t -packet_read (struct packet *packet, - char **data, size_t *data_len, size_t amount) +static error_t +packet_fetch (struct packet *packet, + char **data, size_t *data_len, size_t amount, int remove) { char *start = packet->buf_start; char *end = packet->buf_end; @@ -367,7 +367,7 @@ packet_read (struct packet *packet, { char *buf = packet->buf; - if (packet->buf_vm_alloced && amount >= vm_page_size) + if (remove && packet->buf_vm_alloced && amount >= vm_page_size) /* We can return memory from BUF directly without copying. */ { if (buf + vm_page_size <= start) @@ -414,7 +414,7 @@ packet_read (struct packet *packet, bcopy (start, *data, amount); start += amount; - if (start - buf > 2 * PACKET_SIZE_LARGE) + if (remove && start - buf > 2 * PACKET_SIZE_LARGE) /* Get rid of unused space at the beginning of the buffer -- we know it's vm_alloced because of the size, and this will allow the buffer to just slide through memory. Because we wait for @@ -430,10 +430,33 @@ packet_read (struct packet *packet, packet->buf_len -= dealloc; } - packet->buf_start = start; + if (remove) + packet->buf_start = start; } } *data_len = amount; return 0; } + +/* Removes up to AMOUNT bytes from the beginning of the data in PACKET, and + puts it into *DATA, and the amount read into DATA_LEN. If more than the + original *DATA_LEN bytes are available, new memory is vm_allocated, and + the address and length of this array put into DATA and DATA_LEN. */ +error_t +packet_read (struct packet *packet, + char **data, size_t *data_len, size_t amount) +{ + return packet_fetch (packet, data, data_len, amount, 1); +} + +/* Peek up to AMOUNT bytes from the beginning of the data in PACKET, and + puts it into *DATA, and the amount read into DATA_LEN. If more than the + original *DATA_LEN bytes are available, new memory is vm_allocated, and + the address and length of this array put into DATA and DATA_LEN. */ +error_t +packet_peek (struct packet *packet, + char **data, size_t *data_len, size_t amount) +{ + return packet_fetch (packet, data, data_len, amount, 0); +} |