0.7.4.18: Fixing Alpha fixes
[sbcl.git] / src / runtime / os-common.c
1 /*
2  * This software is part of the SBCL system. See the README file for
3  * more information.
4  *
5  * This software is derived from the CMU CL system, which was
6  * written at Carnegie Mellon University and released into the
7  * public domain. The software is in the public domain and is
8  * provided with absolutely no warranty. See the COPYING and CREDITS
9  * files for more information.
10  */
11
12 #include <stdio.h>
13 #include <errno.h>
14 #include <strings.h>
15
16 #include "os.h"
17 #include "interr.h"
18
19 /* Except for os_zero, these routines are only called by Lisp code.
20  * These routines may also be replaced by os-dependent versions
21  * instead. See hpux-os.c for some useful restrictions on actual
22  * usage. */
23
24 void
25 os_zero(os_vm_address_t addr, os_vm_size_t length)
26 {
27     os_vm_address_t block_start;
28     os_vm_size_t block_size;
29
30 #ifdef DEBUG
31     fprintf(stderr,";;; os_zero: addr: 0x%08x, len: 0x%08x\n",addr,length);
32 #endif
33
34     block_start = os_round_up_to_page(addr);
35
36     length -= block_start-addr;
37     block_size = os_trunc_size_to_page(length);
38
39     if (block_start > addr)
40         bzero((char *)addr, block_start-addr);
41     if (block_size < length)
42         bzero((char *)block_start+block_size, length-block_size);
43
44     if (block_size != 0) {
45         /* Now deallocate and allocate the block so that it faults in
46          * zero-filled. */
47
48         os_invalidate(block_start, block_size);
49         addr = os_validate(block_start, block_size);
50
51         if (addr == NULL || addr != block_start)
52             lose("os_zero: block moved! 0x%08x ==> 0x%08x",
53                  block_start,
54                  addr);
55     }
56 }
57
58 os_vm_address_t
59 os_allocate(os_vm_size_t len)
60 {
61     return os_validate((os_vm_address_t)NULL, len);
62 }
63
64 os_vm_address_t
65 os_allocate_at(os_vm_address_t addr, os_vm_size_t len)
66 {
67     return os_validate(addr, len);
68 }
69
70 void
71 os_deallocate(os_vm_address_t addr, os_vm_size_t len)
72 {
73     os_invalidate(addr,len);
74 }
75
76 /* (This function once tried to grow the chunk by asking os_validate
77  * whether the space was available, but that really only works under
78  * Mach.) */
79 os_vm_address_t
80 os_reallocate(os_vm_address_t addr, os_vm_size_t old_len, os_vm_size_t len)
81 {
82     addr=os_trunc_to_page(addr);
83     len=os_round_up_size_to_page(len);
84     old_len=os_round_up_size_to_page(old_len);
85
86     if (addr==NULL)
87         return os_allocate(len);
88     else{
89         long len_diff=len-old_len;
90
91         if (len_diff<0)
92             os_invalidate(addr+len,-len_diff);
93         else{
94             if (len_diff!=0) {
95               os_vm_address_t new=os_allocate(len);
96
97               if(new!=NULL){
98                 bcopy(addr,new,old_len);
99                 os_invalidate(addr,old_len);
100                 }
101                 
102               addr=new;
103             }
104         }
105         return addr;
106     }
107 }
108
109 int
110 os_get_errno(void)
111 {
112     return errno;
113 }