| 1 | /* Emulation of getpagesize() for systems that need it. */
|
|---|
| 2 |
|
|---|
| 3 | /*
|
|---|
| 4 |
|
|---|
| 5 | NAME
|
|---|
| 6 |
|
|---|
| 7 | getpagesize -- return the number of bytes in page of memory
|
|---|
| 8 |
|
|---|
| 9 | SYNOPSIS
|
|---|
| 10 |
|
|---|
| 11 | int getpagesize (void)
|
|---|
| 12 |
|
|---|
| 13 | DESCRIPTION
|
|---|
| 14 |
|
|---|
| 15 | Returns the number of bytes in a page of memory. This is the
|
|---|
| 16 | granularity of many of the system memory management routines.
|
|---|
| 17 | No guarantee is made as to whether or not it is the same as the
|
|---|
| 18 | basic memory management hardware page size.
|
|---|
| 19 |
|
|---|
| 20 | BUGS
|
|---|
| 21 |
|
|---|
| 22 | Is intended as a reasonable replacement for systems where this
|
|---|
| 23 | is not provided as a system call. The value of 4096 may or may
|
|---|
| 24 | not be correct for the systems where it is returned as the default
|
|---|
| 25 | value.
|
|---|
| 26 |
|
|---|
| 27 | */
|
|---|
| 28 |
|
|---|
| 29 | #ifndef VMS
|
|---|
| 30 |
|
|---|
| 31 | #include "config.h"
|
|---|
| 32 |
|
|---|
| 33 | #include <sys/types.h>
|
|---|
| 34 | #ifdef HAVE_SYS_PARAM_H
|
|---|
| 35 | #include <sys/param.h>
|
|---|
| 36 | #endif
|
|---|
| 37 |
|
|---|
| 38 | #undef GNU_OUR_PAGESIZE
|
|---|
| 39 | #if defined (HAVE_SYSCONF) && defined (HAVE_UNISTD_H)
|
|---|
| 40 | #include <unistd.h>
|
|---|
| 41 | #ifdef _SC_PAGESIZE
|
|---|
| 42 | #define GNU_OUR_PAGESIZE sysconf(_SC_PAGESIZE)
|
|---|
| 43 | #endif
|
|---|
| 44 | #endif
|
|---|
| 45 |
|
|---|
| 46 | #ifndef GNU_OUR_PAGESIZE
|
|---|
| 47 | # ifdef PAGESIZE
|
|---|
| 48 | # define GNU_OUR_PAGESIZE PAGESIZE
|
|---|
| 49 | # else /* no PAGESIZE */
|
|---|
| 50 | # ifdef EXEC_PAGESIZE
|
|---|
| 51 | # define GNU_OUR_PAGESIZE EXEC_PAGESIZE
|
|---|
| 52 | # else /* no EXEC_PAGESIZE */
|
|---|
| 53 | # ifdef NBPG
|
|---|
| 54 | # define GNU_OUR_PAGESIZE (NBPG * CLSIZE)
|
|---|
| 55 | # ifndef CLSIZE
|
|---|
| 56 | # define CLSIZE 1
|
|---|
| 57 | # endif /* CLSIZE */
|
|---|
| 58 | # else /* no NBPG */
|
|---|
| 59 | # ifdef NBPC
|
|---|
| 60 | # define GNU_OUR_PAGESIZE NBPC
|
|---|
| 61 | # else /* no NBPC */
|
|---|
| 62 | # define GNU_OUR_PAGESIZE 4096 /* Just punt and use reasonable value */
|
|---|
| 63 | # endif /* NBPC */
|
|---|
| 64 | # endif /* NBPG */
|
|---|
| 65 | # endif /* EXEC_PAGESIZE */
|
|---|
| 66 | # endif /* PAGESIZE */
|
|---|
| 67 | #endif /* GNU_OUR_PAGESIZE */
|
|---|
| 68 |
|
|---|
| 69 | int
|
|---|
| 70 | getpagesize ()
|
|---|
| 71 | {
|
|---|
| 72 | return (GNU_OUR_PAGESIZE);
|
|---|
| 73 | }
|
|---|
| 74 |
|
|---|
| 75 | #else /* VMS */
|
|---|
| 76 |
|
|---|
| 77 | #if 0 /* older distributions of gcc-vms are missing <syidef.h> */
|
|---|
| 78 | #include <syidef.h>
|
|---|
| 79 | #endif
|
|---|
| 80 | #ifndef SYI$_PAGE_SIZE /* VMS V5.4 and earlier didn't have this yet */
|
|---|
| 81 | #define SYI$_PAGE_SIZE 4452
|
|---|
| 82 | #endif
|
|---|
| 83 | extern unsigned long lib$getsyi(const unsigned short *,...);
|
|---|
| 84 |
|
|---|
| 85 | int getpagesize ()
|
|---|
| 86 | {
|
|---|
| 87 | long pagsiz = 0L;
|
|---|
| 88 | unsigned short itmcod = SYI$_PAGE_SIZE;
|
|---|
| 89 |
|
|---|
| 90 | (void) lib$getsyi (&itmcod, (void *) &pagsiz);
|
|---|
| 91 | if (pagsiz == 0L)
|
|---|
| 92 | pagsiz = 512L; /* VAX default */
|
|---|
| 93 | return (int) pagsiz;
|
|---|
| 94 | }
|
|---|
| 95 |
|
|---|
| 96 | #endif /* VMS */
|
|---|
