diff options
Diffstat (limited to 'mdk-stage1/dietlibc/lib/alloc.c')
| -rw-r--r-- | mdk-stage1/dietlibc/lib/alloc.c | 243 |
1 files changed, 0 insertions, 243 deletions
diff --git a/mdk-stage1/dietlibc/lib/alloc.c b/mdk-stage1/dietlibc/lib/alloc.c deleted file mode 100644 index 8cb87a69b..000000000 --- a/mdk-stage1/dietlibc/lib/alloc.c +++ /dev/null @@ -1,243 +0,0 @@ -/* - * malloc/free by O.Dreesen - */ - -#include <linux/unistd.h> -#include <asm/mman.h> -#include <linux/errno.h> -#include "dietfeatures.h" - -#if 0 -#include <sys/mman.h> -#define _LIBC -#include <errno.h> -#endif - -#include <linux/types.h> - -#if defined(MAP_ANONYMOUS) && !defined(MAP_ANON) -#define MAP_ANON MAP_ANONYMOUS -#endif - -#ifndef MAP_FAILED -#define MAP_FAILED ((void*)-1) -#endif - -#ifndef NULL -#define NULL ((void*)0) -#endif - -extern void * mmap(void *start, size_t length, int prot , int flags, int fd, off_t offset); -extern void *memset(void *s, int c, size_t n); -extern void *memcpy(void *dest, const void *src, size_t n); - -typedef struct t_alloc_head { - unsigned int magic1; - struct t_alloc_head *ptr; - unsigned long size; - unsigned int magic2; -} alloc_head; - -/* guess what ? the virtual block size */ -#define MEM_BLOCK_SIZE 4096 - -/* minimum allocated bytes */ -#define MEM_ALLOC_MIN 4 - -/* Initial start position in memory */ -#define MEM_ALLOC_START ((char*)0x18000000) - -/* Make every block align */ -#define MEM_ALIGN(s) (((s)+MEM_ALLOC_MIN-1)&(~(MEM_ALLOC_MIN-1))) -#define PAGE_ALIGN(s) (((s)+MEM_BLOCK_SIZE-1)&(~(MEM_BLOCK_SIZE-1))) -#define PAGE_ALIGNP(p) ((char*)PAGE_ALIGN((size_t)(p))) - -#define END_OF_BLOCK(p) ((alloc_head*)(((char*)(p))+((p)->size))) -#define START_BLOCK(p) ((alloc_head*)(((char*)(p))-sizeof(alloc_head))) -#define START_DATA(p) (((char*)(p))+sizeof(alloc_head)) -#define MIN_ALLOC(s) (((((s)+sizeof(alloc_head)-1)/MEM_ALLOC_MIN)+1)*MEM_ALLOC_MIN) - -#define ALLOC_MAGIC1 0xbad2f7ee -#define ALLOC_MAGIC2 0xf7ee2bad - -/* freelist handler */ -static alloc_head base = {ALLOC_MAGIC1,&base,0,ALLOC_MAGIC2}; -static char *alloc_get_end = MEM_ALLOC_START; - -void __libc_free(void *ptr) -{ - alloc_head *prev,*p,*block; - - if (ptr==NULL) return; - - block=START_BLOCK(ptr); - if (block->magic1 != ALLOC_MAGIC1) return; - if (block->magic2 != ALLOC_MAGIC2) return; - - prev=&base; - for (p=prev->ptr ; ; prev=p, p=p->ptr) - { - if ((block>prev)&&(block<p)) break; /* found the gap block belongs */ - if ((prev>p)&&(block<p)) break; /* block pre freelist */ - if ((prev>p)&&(block>prev)) break; /* block after freelist */ - - /* emergency escape: freelist has ONLY one entry the freelist base */ - if (p->ptr==p) break; - } - prev->ptr = block; - - if (END_OF_BLOCK(block)==p) - { /* join right neighbor */ - block->ptr = p->ptr; - block->size += p->size; - } - else - block->ptr = p; - - if (END_OF_BLOCK(prev)==block) - { /* join left neighbor */ - prev->size += block->size; - prev->ptr = block->ptr; - } -} -void free(void *ptr) __attribute__((weak,alias("__libc_free"))); - -static void *alloc_get_mem(unsigned long size) -{ - char *tmp; - alloc_head *ah; - - size=PAGE_ALIGN(size); - - /* map free pages @ alloc_get_end */ - tmp=mmap(alloc_get_end, size, PROT_READ|PROT_WRITE, - MAP_ANONYMOUS|MAP_PRIVATE|MAP_FIXED, -1, 0); - if (tmp==MAP_FAILED) - { - /* OK we can't map free pages @ alloc_get_end so try free position */ - tmp=mmap(0, size, PROT_READ|PROT_WRITE, - MAP_ANONYMOUS|MAP_PRIVATE, -1, 0); - if (tmp==MAP_FAILED) - { - errno = ENOMEM; - return NULL; /* PANIC ! */ - } - alloc_get_end=tmp; - } - - alloc_get_end+=size; - - /* make a header */ - ah=(alloc_head*)tmp; - ah->magic1=ALLOC_MAGIC1; - ah->magic2=ALLOC_MAGIC2; - ah->ptr=ah; - ah->size=size; - - /* link new free maped pages in freelist */ - __libc_free(START_DATA(tmp)); - - return &base; -} - -void *__libc_malloc(size_t size) -{ - alloc_head *p, *prev; - size_t need; - - /* needed MEM_ALLOC_MIN */ - need=MIN_ALLOC(size); - - prev=&base; - for (p=prev->ptr;;prev=p,p=p->ptr) - { - if (p->size>=need) - { - if (p->size==need) - { /* fit PERFECT */ - prev->ptr=p->ptr; /* relink freelist */ - } - else - { - alloc_head *tmp=(alloc_head*)(((char*)p)+need); - if ((p->size-need)<sizeof(alloc_head)) - { /* work around: if there is not enough space for freelist head. - * this waste some bytes ( < sizeof(alloc_head) ) */ - need=p->size; - prev->ptr=p->ptr; /* relink freelist */ - } - else - { - prev->ptr=tmp; - tmp->magic1=ALLOC_MAGIC1; - tmp->magic2=ALLOC_MAGIC2; - tmp->ptr=p->ptr; - tmp->size=p->size-need; /* remaining size */ - } - - p->size=need; /* set size */ - } - p->ptr=p; /* self-link */ - - return (void*)START_DATA(p); - } - else if (p==&base) - { - if ((p=alloc_get_mem(need))==NULL) goto err_out; - } - } -err_out: - return NULL; -} -void *malloc(size_t size) __attribute__((weak,alias("__libc_malloc"))); - -void *calloc(size_t nmemb,size_t size) -{ - size_t n=nmemb*size; - void *tmp=malloc(n); - if (tmp) memset(tmp,0,n); - return tmp; -} - -void *realloc(void *ptr,size_t size) -{ - alloc_head *tmp=0,*tf=0; - long need=0; - long diff=0; - - if (ptr) - { - if (size) - { - tmp=START_BLOCK(ptr); - need=MIN_ALLOC(size); /* only this size will survive */ - diff=tmp->size-need; - if (diff<0) - { - if ((tf=malloc(size))) - { - memcpy(tf,ptr,tmp->size-sizeof(alloc_head)); - free(ptr); - return tf; - } - return NULL; - } - if (diff>=sizeof(alloc_head)) - { - tmp->size=need; - tf=END_OF_BLOCK(tmp); - tf->magic1=ALLOC_MAGIC1; - tf->magic2=ALLOC_MAGIC2; - tf->ptr=tf; - tf->size=diff; - free(START_DATA(tf)); - } - return ptr; - } - else - free(ptr); - } - else if (size>0) - return malloc(size); - return NULL; -} |