system/freebsd-src
system/freebsd-src
1
0
Fork 0
mirror of https://github.com/freebsd/freebsd-src synced 2024-07-21 10:19:04 +00:00
Code Issues Actions 2 Packages Projects Releases Wiki Activity

rtld_malloc: add __crt_aligned_alloc_offset()

Browse source 
(cherry picked from commit c29ee08204)
This commit is contained in:
Konstantin Belousov 2023-07-22 07:21:45 +03:00
parent 0c8823bad5
commit a3a71ddc77
2 changed files with 32 additions and 3 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

34
libexec/rtld-elf/rtld_malloc.c
View file

@ -86,13 +86,15 @@ static void morecore(int bucket);
static int morepages(int n);
#define MAGIC 0xef /* magic # on accounting info */
#define AMAGIC 0xdf /* magic # for aligned alloc */
/*
* nextf[i] is the pointer to the next free block of size
* (FIRST_BUCKET_SIZE << i). The overhead information precedes the data
* area returned to the user.
*/
#define FIRST_BUCKET_SIZE 8
#define LOW_BITS 3
#define FIRST_BUCKET_SIZE (1U << LOW_BITS)
#define NBUCKETS 30
static union overhead *nextf[NBUCKETS];
@ -169,6 +171,28 @@ __crt_calloc(size_t num, size_t size)
return (ret);
}
void *
__crt_aligned_alloc_offset(size_t align, size_t size, size_t offset)
{
void *mem, *ov;
union overhead ov1;
uintptr_t x;
if (align < FIRST_BUCKET_SIZE)
align = FIRST_BUCKET_SIZE;
offset &= align - 1;
mem = __crt_malloc(size + align + offset + sizeof(union overhead));
if (mem == NULL)
return (NULL);
x = roundup2((uintptr_t)mem + sizeof(union overhead), align);
x += offset;
ov = cp2op((void *)x);
ov1.ov_magic = AMAGIC;
ov1.ov_index = x - (uintptr_t)mem - sizeof(union overhead);
memcpy(ov, &ov1, sizeof(ov1));
return ((void *)x);
}
/*
* Allocate more memory to the indicated bucket.
*/
@ -210,12 +234,16 @@ morecore(int bucket)
void
__crt_free(void *cp)
{
union overhead *op, op1;
void *opx;
int size;
union overhead *op;
if (cp == NULL)
return;
op = cp2op(cp);
opx = cp2op(cp);
memcpy(&op1, opx, sizeof(op1));
op = op1.ov_magic == AMAGIC ? (void *)((caddr_t)cp - op1.ov_index) :
opx;
if (op->ov_magic != MAGIC)
return; /* sanity */
size = op->ov_index;

1
libexec/rtld-elf/rtld_malloc.h
View file

@ -32,6 +32,7 @@
#ifndef RTLD_MALLOC_H
#define RTLD_MALLOC_H
void *__crt_aligned_alloc_offset(size_t align, size_t size, size_t offset);
void *__crt_calloc(size_t num, size_t size);
void __crt_free(void *cp);
void *__crt_malloc(size_t nbytes);