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authorUlrich Drepper <drepper@redhat.com>2000-01-02 06:01:06 +0000
committerUlrich Drepper <drepper@redhat.com>2000-01-02 06:01:06 +0000
commit8d6f1731fcd082e4f744ba9cb4bde4be7c08f1b3 (patch)
tree099a250d7366aef2ab028fdb24f0d692cd784b4a /db2/os/os_map.c
parent9a6450d578556c11e7c173d2f28362345b8f1258 (diff)
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Update.
* Makeconfig (all-subdirs): Remove db and db2. * db/*: Removed. * db2/*: Removed.
Diffstat (limited to 'db2/os/os_map.c')
-rw-r--r--db2/os/os_map.c447
1 files changed, 0 insertions, 447 deletions
diff --git a/db2/os/os_map.c b/db2/os/os_map.c
deleted file mode 100644
index 5664a2edec..0000000000
--- a/db2/os/os_map.c
+++ /dev/null
@@ -1,447 +0,0 @@
-/*-
- * See the file LICENSE for redistribution information.
- *
- * Copyright (c) 1996, 1997, 1998
- * Sleepycat Software. All rights reserved.
- */
-
-#include "config.h"
-
-#ifndef lint
-static const char sccsid[] = "@(#)os_map.c 10.24 (Sleepycat) 10/12/98";
-#endif /* not lint */
-
-#ifndef NO_SYSTEM_INCLUDES
-#include <sys/types.h>
-#ifdef HAVE_MMAP
-#include <sys/mman.h>
-#endif
-
-#ifdef HAVE_SHMGET
-#include <sys/ipc.h>
-#include <sys/shm.h>
-#endif
-
-#include <errno.h>
-#include <string.h>
-#endif
-
-#include "db_int.h"
-#include "os_jump.h"
-#include "common_ext.h"
-
-#ifdef HAVE_MMAP
-static int __os_map __P((char *, int, size_t, int, int, int, void **));
-#endif
-#ifdef HAVE_SHMGET
-static int __os_shmget __P((REGINFO *));
-#endif
-
-/*
- * __db_mapanon_ok --
- * Return if this OS can support anonymous memory regions.
- *
- * PUBLIC: int __db_mapanon_ok __P((int));
- */
-int
-__db_mapanon_ok(need_names)
- int need_names;
-{
- int ret;
-
- ret = EINVAL;
-
- /*
- * If we don't have spinlocks, we have to have a file descriptor
- * for fcntl(2) locking, which implies using mmap(2) to map in a
- * regular file. Theoretically, we could probably find ways to
- * get a file descriptor to lock other types of shared regions,
- * but I don't see any reason to do so.
- *
- * If need_names is set, the application wants to share anonymous
- * memory among multiple processes, so we have to have a way to
- * name it. This requires shmget(2), on UNIX systems.
- */
-#ifdef HAVE_SPINLOCKS
-#ifdef HAVE_SHMGET
- ret = 0;
-#endif
-#ifdef HAVE_MMAP
-#ifdef MAP_ANON
- if (!need_names)
- ret = 0;
-#endif
-#ifdef MAP_ANONYMOUS
- if (!need_names)
- ret = 0;
-#endif
-#else
- COMPQUIET(need_names, 0);
-#endif /* HAVE_MMAP */
-#endif /* HAVE_SPINLOCKS */
-
- return (ret);
-}
-
-/*
- * __db_mapinit --
- * Return if shared regions need to be initialized.
- *
- * PUBLIC: int __db_mapinit __P((void));
- */
-int
-__db_mapinit()
-{
- /*
- * Historically, some systems required that all of the bytes of the
- * region be written before it could be mmapped and accessed randomly.
- * We have the option of setting REGION_INIT_NEEDED at configuration
- * time if we're running on one of those systems.
- */
-#ifdef REGION_INIT_NEEDED
- return (1);
-#else
- return (0);
-#endif
-}
-
-/*
- * __db_mapregion --
- * Attach to a shared memory region.
- *
- * PUBLIC: int __db_mapregion __P((char *, REGINFO *));
- */
-int
-__db_mapregion(path, infop)
- char *path;
- REGINFO *infop;
-{
- int called, ret;
-
- called = 0;
- ret = EINVAL;
-
- /* If the user replaces the map call, call through their interface. */
- if (__db_jump.j_map != NULL) {
- F_SET(infop, REGION_HOLDINGSYS);
- return (__db_jump.j_map(path, infop->fd, infop->size,
- 1, F_ISSET(infop, REGION_ANONYMOUS), 0, &infop->addr));
- }
-
- if (F_ISSET(infop, REGION_ANONYMOUS)) {
- /*
- * !!!
- * If we're creating anonymous regions:
- *
- * If it's private, we use mmap(2). The problem with using
- * shmget(2) is that we may be creating a region of which the
- * application isn't aware, and if the application crashes
- * we'll have no way to remove the system resources for the
- * region.
- *
- * If it's not private, we use the shmget(2) interface if it's
- * available, because it allows us to name anonymous memory.
- * If shmget(2) isn't available, use the mmap(2) calls.
- *
- * In the case of anonymous memory, using mmap(2) means the
- * memory isn't named and only the single process and its
- * threads can access the region.
- */
-#ifdef HAVE_MMAP
-#ifdef MAP_ANON
-#define HAVE_MMAP_ANONYMOUS 1
-#else
-#ifdef MAP_ANONYMOUS
-#define HAVE_MMAP_ANONYMOUS 1
-#endif
-#endif
-#endif
-#ifdef HAVE_MMAP_ANONYMOUS
- if (!called && F_ISSET(infop, REGION_PRIVATE)) {
- called = 1;
- ret = __os_map(path,
- infop->fd, infop->size, 1, 1, 0, &infop->addr);
- }
-#endif
-#ifdef HAVE_SHMGET
- if (!called) {
- called = 1;
- ret = __os_shmget(infop);
- }
-#endif
-#ifdef HAVE_MMAP
- /*
- * If we're trying to join an unnamed anonymous region, fail --
- * that's not possible.
- */
- if (!called) {
- called = 1;
-
- if (!F_ISSET(infop, REGION_CREATED)) {
- __db_err(infop->dbenv,
- "cannot join region in unnamed anonymous memory");
- return (EINVAL);
- }
-
- ret = __os_map(path,
- infop->fd, infop->size, 1, 1, 0, &infop->addr);
- }
-#endif
- } else {
- /*
- * !!!
- * If we're creating normal regions, we use the mmap(2)
- * interface if it's available because it's POSIX 1003.1
- * standard and we trust it more than we do shmget(2).
- */
-#ifdef HAVE_MMAP
- if (!called) {
- called = 1;
-
- /* Mmap(2) regions that aren't anonymous can grow. */
- F_SET(infop, REGION_CANGROW);
-
- ret = __os_map(path,
- infop->fd, infop->size, 1, 0, 0, &infop->addr);
- }
-#endif
-#ifdef HAVE_SHMGET
- if (!called) {
- called = 1;
- ret = __os_shmget(infop);
- }
-#endif
- }
- return (ret);
-}
-
-/*
- * __db_unmapregion --
- * Detach from the shared memory region.
- *
- * PUBLIC: int __db_unmapregion __P((REGINFO *));
- */
-int
-__db_unmapregion(infop)
- REGINFO *infop;
-{
- int called, ret;
-
- called = 0;
- ret = EINVAL;
-
- if (__db_jump.j_unmap != NULL)
- return (__db_jump.j_unmap(infop->addr, infop->size));
-
-#ifdef HAVE_SHMGET
- if (infop->segid != INVALID_SEGID) {
- called = 1;
- ret = shmdt(infop->addr) ? errno : 0;
- }
-#endif
-#ifdef HAVE_MMAP
- if (!called) {
- called = 1;
- ret = munmap(infop->addr, infop->size) ? errno : 0;
- }
-#endif
- return (ret);
-}
-
-/*
- * __db_unlinkregion --
- * Remove the shared memory region.
- *
- * PUBLIC: int __db_unlinkregion __P((char *, REGINFO *));
- */
-int
-__db_unlinkregion(name, infop)
- char *name;
- REGINFO *infop;
-{
- int called, ret;
-
- called = 0;
- ret = EINVAL;
-
- if (__db_jump.j_runlink != NULL)
- return (__db_jump.j_runlink(name));
-
-#ifdef HAVE_SHMGET
- if (infop->segid != INVALID_SEGID) {
- called = 1;
- ret = shmctl(infop->segid, IPC_RMID, NULL) ? errno : 0;
- }
-#endif
-#ifdef HAVE_MMAP
- COMPQUIET(infop, NULL);
- if (!called) {
- called = 1;
- ret = 0;
- }
-#endif
- return (ret);
-}
-
-/*
- * __db_mapfile --
- * Map in a shared memory file.
- *
- * PUBLIC: int __db_mapfile __P((char *, int, size_t, int, void **));
- */
-int
-__db_mapfile(path, fd, len, is_rdonly, addr)
- char *path;
- int fd, is_rdonly;
- size_t len;
- void **addr;
-{
- if (__db_jump.j_map != NULL)
- return (__db_jump.j_map(path, fd, len, 0, 0, is_rdonly, addr));
-
-#ifdef HAVE_MMAP
- return (__os_map(path, fd, len, 0, 0, is_rdonly, addr));
-#else
- return (EINVAL);
-#endif
-}
-
-/*
- * __db_unmapfile --
- * Unmap the shared memory file.
- *
- * PUBLIC: int __db_unmapfile __P((void *, size_t));
- */
-int
-__db_unmapfile(addr, len)
- void *addr;
- size_t len;
-{
- if (__db_jump.j_unmap != NULL)
- return (__db_jump.j_unmap(addr, len));
-
-#ifdef HAVE_MMAP
- return (munmap(addr, len) ? errno : 0);
-#else
- return (EINVAL);
-#endif
-}
-
-#ifdef HAVE_MMAP
-/*
- * __os_map --
- * Call the mmap(2) function.
- */
-static int
-__os_map(path, fd, len, is_region, is_anonymous, is_rdonly, addr)
- char *path;
- int fd, is_region, is_anonymous, is_rdonly;
- size_t len;
- void **addr;
-{
- void *p;
- int flags, prot;
-
- COMPQUIET(path, NULL);
-
- /*
- * If it's read-only, it's private, and if it's not, it's shared.
- * Don't bother with an additional parameter.
- */
- flags = is_rdonly ? MAP_PRIVATE : MAP_SHARED;
-
- if (is_region && is_anonymous) {
- /*
- * BSD derived systems use MAP_ANON; Digital Unix and HP/UX
- * use MAP_ANONYMOUS.
- */
-#ifdef MAP_ANON
- flags |= MAP_ANON;
-#endif
-#ifdef MAP_ANONYMOUS
- flags |= MAP_ANONYMOUS;
-#endif
- fd = -1;
- }
-#ifdef MAP_FILE
- if (!is_region || !is_anonymous) {
- /*
- * Historically, MAP_FILE was required for mapping regular
- * files, even though it was the default. Some systems have
- * it, some don't, some that have it set it to 0.
- */
- flags |= MAP_FILE;
- }
-#endif
-
- /*
- * I know of no systems that implement the flag to tell the system
- * that the region contains semaphores, but it's not an unreasonable
- * thing to do, and has been part of the design since forever. I
- * don't think anyone will object, but don't set it for read-only
- * files, it doesn't make sense.
- */
-#ifdef MAP_HASSEMAPHORE
- if (!is_rdonly)
- flags |= MAP_HASSEMAPHORE;
-#endif
-
- prot = PROT_READ | (is_rdonly ? 0 : PROT_WRITE);
-
-/*
- * XXX
- * Work around a bug in the VMS V7.1 mmap() implementation. To map a file
- * into memory on VMS it needs to be opened in a certain way, originally.
- * To get the file opened in that certain way, the VMS mmap() closes the
- * file and re-opens it. When it does this, it doesn't flush any caches
- * out to disk before closing. The problem this causes us is that when the
- * memory cache doesn't get written out, the file isn't big enough to match
- * the memory chunk and the mmap() call fails. This call to fsync() fixes
- * the problem. DEC thinks this isn't a bug because of language in XPG5
- * discussing user responsibility for on-disk and in-memory synchronization.
- */
-#ifdef VMS
- if (__os_fsync(fd) == -1)
- return(errno);
-#endif
-
- /* MAP_FAILED was not defined in early mmap implementations. */
-#ifndef MAP_FAILED
-#define MAP_FAILED -1
-#endif
- if ((p =
- mmap(NULL, len, prot, flags, fd, (off_t)0)) == (void *)MAP_FAILED)
- return (errno);
-
- *addr = p;
- return (0);
-}
-#endif
-
-#ifdef HAVE_SHMGET
-/*
- * __os_shmget --
- * Call the shmget(2) family of functions.
- */
-static int
-__os_shmget(infop)
- REGINFO *infop;
-{
- if (F_ISSET(infop, REGION_CREATED) &&
- (infop->segid = shmget(0, infop->size, IPC_PRIVATE | 0600)) == -1)
- return (errno);
-
- if ((infop->addr = shmat(infop->segid, NULL, 0)) == (void *)-1) {
- /*
- * If we're trying to join the region and failing, assume
- * that there was a reboot and the region no longer exists.
- */
- if (!F_ISSET(infop, REGION_CREATED))
- errno = EAGAIN;
- return (errno);
- }
-
- F_SET(infop, REGION_HOLDINGSYS);
- return (0);
-}
-#endif