53 lines
1.2 KiB
C
53 lines
1.2 KiB
C
#define _GNU_SOURCE
|
|
#include <stdlib.h>
|
|
#include <unistd.h>
|
|
#include <sys/mman.h>
|
|
#include <sys/fcntl.h>
|
|
#include <sys/shm.h>
|
|
#include <stdio.h>
|
|
#include "byte.h"
|
|
#include "mstorage.h"
|
|
|
|
#ifndef PAGE_SIZE
|
|
#define PAGE_SIZE 4096
|
|
#endif
|
|
|
|
#define PAGEMASK ((PAGE_SIZE)-1)
|
|
|
|
const long mstorage_add(mstorage_t* p,const char* s,unsigned long n) {
|
|
if (p->mapped-p->used<n) {
|
|
if (!p->root) {
|
|
/* nothing allocated. mmap /dev/zero */
|
|
#ifndef MAP_ANONYMOUS
|
|
int fd=open("/dev/zero",O_RDWR);
|
|
#endif
|
|
char* tmp;
|
|
long need=(n|PAGEMASK)+1;
|
|
#ifdef MAP_ANONYMOUS
|
|
if ((tmp=mmap(0,need,PROT_READ|PROT_WRITE,MAP_PRIVATE|MAP_ANONYMOUS,-1,0))==MAP_FAILED)
|
|
#else
|
|
if (fd<0) return -1;
|
|
if ((tmp=mmap(0,need,PROT_READ|PROT_WRITE,MAP_PRIVATE,fd,0))==MAP_FAILED)
|
|
#endif
|
|
return -1;
|
|
p->root=tmp;
|
|
p->mapped=need;
|
|
p->used=0;
|
|
#ifndef MAP_ANONYMOUS
|
|
close(fd);
|
|
#endif
|
|
} else {
|
|
long need=((p->used+n)|PAGEMASK)+1;
|
|
char* tmp=mremap(p->root,p->mapped,need,MREMAP_MAYMOVE);
|
|
if (tmp==MAP_FAILED) return -1;
|
|
p->mapped=need; p->root=tmp;
|
|
}
|
|
}
|
|
byte_copy(p->root+p->used,n,s);
|
|
{
|
|
unsigned long l=p->used;
|
|
p->used+=n;
|
|
return l;
|
|
}
|
|
}
|