summaryrefslogtreecommitdiff
path: root/ot_iovec.c
diff options
context:
space:
mode:
authorerdgeist <>2007-11-12 01:37:47 +0000
committererdgeist <>2007-11-12 01:37:47 +0000
commit54bdad552e5c997258467492c0c7d022fb428090 (patch)
treeb83eca1f0d910fd687806a030510fd985c66b513 /ot_iovec.c
parent5da91fd8f240412ec0f543292a7874fe3df1cb14 (diff)
New large chunk allocation code
Diffstat (limited to 'ot_iovec.c')
-rw-r--r--ot_iovec.c60
1 files changed, 60 insertions, 0 deletions
diff --git a/ot_iovec.c b/ot_iovec.c
new file mode 100644
index 0000000..ea3dd23
--- /dev/null
+++ b/ot_iovec.c
@@ -0,0 +1,60 @@
1/* This software was written by Dirk Engling <erdgeist@erdgeist.org>
2 It is considered beerware. Prost. Skol. Cheers or whatever. */
3
4/* System */
5#include <sys/types.h>
6#include <sys/mman.h>
7#include <stdlib.h>
8#include <unistd.h>
9#include <sys/uio.h>
10
11/* Libowfat */
12
13/* Opentracker */
14#include "ot_iovec.h"
15
16void *iovec_increase( int *iovec_entries, struct iovec **iovector, size_t new_alloc ) {
17 void *new_ptr = realloc( *iovector, 1 + *iovec_entries * sizeof( struct iovec ) );
18 if( !new_ptr )
19 return NULL;
20 *iovector = new_ptr;
21 new_ptr = mmap( NULL, new_alloc, PROT_READ | PROT_WRITE, MAP_ANON | MAP_PRIVATE, -1, 0 );
22 if( !new_ptr )
23 return NULL;
24 ((*iovector)[*iovec_entries]).iov_base = new_ptr;
25 ((*iovector)[*iovec_entries]).iov_len = new_alloc;
26 ++*iovec_entries;
27 return new_ptr;
28}
29
30void iovec_free( int *iovec_entries, struct iovec **iovector ) {
31 int i;
32 for( i=0; i<*iovec_entries; ++i )
33 munmap( ((*iovector)[i]).iov_base, ((*iovector)[i]).iov_len );
34 *iovec_entries = 0;
35}
36
37void iovec_fixlast( int *iovec_entries, struct iovec **iovector, size_t new_alloc ) {
38 int page_size = getpagesize();
39 size_t old_alloc, old_pages, new_pages;
40
41 if( !*iovec_entries ) return;
42
43 old_alloc = ((*iovector)[ *iovec_entries - 1 ]).iov_len;
44 old_pages = 1 + old_alloc / page_size;
45 new_pages = 1 + new_alloc / page_size;
46
47 if( old_pages != new_pages ) {
48 munmap( ((char*)((*iovector)[ *iovec_entries - 1 ]).iov_base ) + new_pages * page_size,
49 old_alloc - new_pages * page_size );
50 }
51 ((*iovector)[*iovec_entries - 1 ]).iov_len = new_alloc;
52}
53
54size_t iovec_length( int *iovec_entries, struct iovec **iovector ) {
55 size_t length = 0;
56 int i;
57 for( i=0; i<*iovec_entries; ++i )
58 length += ((*iovector)[i]).iov_len;
59 return length;
60}