- introduce new call numbers, names, and field aliases; - initialize request messages to zero for all ABI calls; - format callnr.h in the same way as com.h; - redo call tables in both servers; - remove param.h namespace pollution in the servers; - make brk(2) go to VM directly, rather than through PM; - remove obsolete BRK, UTIME, and WAIT calls; - clean up path copying routine in VFS; - move remaining system calls from libminlib to libc; - correct some errno-related mistakes in libc routines. Change-Id: I2d8ec5d061cd7e0b30c51ffd77aa72ebf84e2565
713 lines
20 KiB
C
713 lines
20 KiB
C
/* This file contains the procedures for creating, opening, closing, and
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* seeking on files.
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*
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* The entry points into this file are
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* do_open: perform the OPEN system call
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* do_mknod: perform the MKNOD system call
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* do_mkdir: perform the MKDIR system call
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* do_close: perform the CLOSE system call
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* do_lseek: perform the LSEEK system call
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*/
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#include "fs.h"
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#include <sys/stat.h>
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#include <fcntl.h>
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#include <string.h>
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#include <unistd.h>
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#include <minix/callnr.h>
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#include <minix/com.h>
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#include <minix/u64.h>
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#include "file.h"
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#include "scratchpad.h"
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#include "lock.h"
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#include <sys/dirent.h>
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#include <assert.h>
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#include <minix/vfsif.h>
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#include "vnode.h"
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#include "vmnt.h"
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#include "path.h"
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static char mode_map[] = {R_BIT, W_BIT, R_BIT|W_BIT, 0};
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static struct vnode *new_node(struct lookup *resolve, int oflags,
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mode_t bits);
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static int pipe_open(struct vnode *vp, mode_t bits, int oflags);
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/*===========================================================================*
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* do_open *
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*===========================================================================*/
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int do_open(void)
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{
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/* Perform the open(name, flags) system call with O_CREAT *not* set. */
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int open_flags;
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char fullpath[PATH_MAX];
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open_flags = job_m_in.VFS_PATH_FLAGS;
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if (open_flags & O_CREAT)
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return EINVAL;
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if (copy_path(fullpath, sizeof(fullpath)) != OK)
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return(err_code);
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return common_open(fullpath, open_flags, 0 /*omode*/);
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}
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/*===========================================================================*
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* do_creat *
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*===========================================================================*/
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int do_creat(void)
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{
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/* Perform the open(name, flags, mode) system call with O_CREAT set. */
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int open_flags, create_mode;
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char fullpath[PATH_MAX];
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vir_bytes vname;
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size_t vname_length;
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vname = (vir_bytes) job_m_in.VFS_CREAT_NAME;
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vname_length = (size_t) job_m_in.VFS_CREAT_LEN;
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open_flags = job_m_in.VFS_CREAT_FLAGS;
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create_mode = job_m_in.VFS_CREAT_MODE;
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if (!(open_flags & O_CREAT))
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return(EINVAL);
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if (fetch_name(vname, vname_length, fullpath) != OK)
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return(err_code);
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return common_open(fullpath, open_flags, create_mode);
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}
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/*===========================================================================*
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* common_open *
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*===========================================================================*/
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int common_open(char path[PATH_MAX], int oflags, mode_t omode)
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{
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/* Common code from do_creat and do_open. */
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int b, r, exist = TRUE, major_dev;
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dev_t dev;
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mode_t bits;
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struct filp *filp, *filp2;
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struct vnode *vp;
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struct vmnt *vmp;
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struct dmap *dp;
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struct lookup resolve;
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int start = 0;
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/* Remap the bottom two bits of oflags. */
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bits = (mode_t) mode_map[oflags & O_ACCMODE];
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if (!bits) return(EINVAL);
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/* See if file descriptor and filp slots are available. */
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if ((r = get_fd(fp, start, bits, &(scratch(fp).file.fd_nr),
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&filp)) != OK)
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return(r);
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lookup_init(&resolve, path, PATH_NOFLAGS, &vmp, &vp);
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/* If O_CREATE is set, try to make the file. */
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if (oflags & O_CREAT) {
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omode = I_REGULAR | (omode & ALLPERMS & fp->fp_umask);
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vp = new_node(&resolve, oflags, omode);
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r = err_code;
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if (r == OK) exist = FALSE; /* We just created the file */
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else if (r != EEXIST) { /* other error */
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if (vp) unlock_vnode(vp);
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unlock_filp(filp);
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return(r);
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}
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else exist = !(oflags & O_EXCL);/* file exists, if the O_EXCL
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flag is set this is an error */
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} else {
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/* Scan path name */
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resolve.l_vmnt_lock = VMNT_READ;
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resolve.l_vnode_lock = VNODE_OPCL;
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if ((vp = eat_path(&resolve, fp)) == NULL) {
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unlock_filp(filp);
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return(err_code);
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}
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if (vmp != NULL) unlock_vmnt(vmp);
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}
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/* Claim the file descriptor and filp slot and fill them in. */
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fp->fp_filp[scratch(fp).file.fd_nr] = filp;
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filp->filp_count = 1;
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filp->filp_vno = vp;
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filp->filp_flags = oflags;
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if (oflags & O_CLOEXEC)
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FD_SET(scratch(fp).file.fd_nr, &fp->fp_cloexec_set);
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/* Only do the normal open code if we didn't just create the file. */
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if (exist) {
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/* Check protections. */
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if ((r = forbidden(fp, vp, bits)) == OK) {
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/* Opening reg. files, directories, and special files differ */
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switch (vp->v_mode & S_IFMT) {
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case S_IFREG:
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/* Truncate regular file if O_TRUNC. */
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if (oflags & O_TRUNC) {
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if ((r = forbidden(fp, vp, W_BIT)) != OK)
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break;
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upgrade_vnode_lock(vp);
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truncate_vnode(vp, 0);
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}
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break;
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case S_IFDIR:
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/* Directories may be read but not written. */
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r = (bits & W_BIT ? EISDIR : OK);
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break;
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case S_IFCHR:
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/* Invoke the driver for special processing. */
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dev = (dev_t) vp->v_sdev;
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/* TTY needs to know about the O_NOCTTY flag. */
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r = cdev_open(dev, bits | (oflags & O_NOCTTY));
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vp = filp->filp_vno; /* Might be updated by
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* cdev_open after cloning */
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break;
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case S_IFBLK:
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lock_bsf();
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/* Invoke the driver for special processing. */
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dev = (dev_t) vp->v_sdev;
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r = bdev_open(dev, bits);
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if (r != OK) {
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unlock_bsf();
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break;
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}
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major_dev = major(vp->v_sdev);
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dp = &dmap[major_dev];
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if (dp->dmap_driver == NONE) {
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printf("VFS: block driver disappeared!\n");
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unlock_bsf();
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r = ENXIO;
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break;
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}
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/* Check whether the device is mounted or not. If so,
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* then that FS is responsible for this device.
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* Otherwise we default to ROOT_FS.
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*/
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vp->v_bfs_e = ROOT_FS_E; /* By default */
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for (vmp = &vmnt[0]; vmp < &vmnt[NR_MNTS]; ++vmp)
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if (vmp->m_dev == vp->v_sdev &&
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!(vmp->m_flags & VMNT_FORCEROOTBSF)) {
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vp->v_bfs_e = vmp->m_fs_e;
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}
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/* Send the driver label to the file system that will
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* handle the block I/O requests (even when its label
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* and endpoint are known already), but only when it is
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* the root file system. Other file systems will
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* already have it anyway.
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*/
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if (vp->v_bfs_e != ROOT_FS_E) {
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unlock_bsf();
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break;
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}
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if (req_newdriver(vp->v_bfs_e, vp->v_sdev,
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dp->dmap_label) != OK) {
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printf("VFS: error sending driver label\n");
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bdev_close(dev);
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r = ENXIO;
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}
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unlock_bsf();
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break;
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case S_IFIFO:
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/* Create a mapped inode on PFS which handles reads
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and writes to this named pipe. */
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upgrade_vnode_lock(vp);
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r = map_vnode(vp, PFS_PROC_NR);
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if (r == OK) {
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if (vp->v_ref_count == 1) {
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if (vp->v_size != 0)
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r = truncate_vnode(vp, 0);
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}
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oflags |= O_APPEND; /* force append mode */
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filp->filp_flags = oflags;
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}
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if (r == OK) {
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r = pipe_open(vp, bits, oflags);
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}
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if (r != ENXIO) {
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/* See if someone else is doing a rd or wt on
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* the FIFO. If so, use its filp entry so the
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* file position will be automatically shared.
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*/
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b = (bits & R_BIT ? R_BIT : W_BIT);
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filp->filp_count = 0; /* don't find self */
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if ((filp2 = find_filp(vp, b)) != NULL) {
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/* Co-reader or writer found. Use it.*/
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fp->fp_filp[scratch(fp).file.fd_nr] = filp2;
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filp2->filp_count++;
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filp2->filp_vno = vp;
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filp2->filp_flags = oflags;
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/* v_count was incremented after the vnode
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* has been found. i_count was incremented
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* incorrectly in FS, not knowing that we
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* were going to use an existing filp
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* entry. Correct this error.
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*/
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unlock_vnode(vp);
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put_vnode(vp);
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} else {
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/* Nobody else found. Restore filp. */
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filp->filp_count = 1;
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}
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}
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break;
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}
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}
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}
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unlock_filp(filp);
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/* If error, release inode. */
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if (r != OK) {
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if (r != SUSPEND) {
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fp->fp_filp[scratch(fp).file.fd_nr] = NULL;
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filp->filp_count = 0;
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filp->filp_vno = NULL;
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put_vnode(vp);
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}
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} else {
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r = scratch(fp).file.fd_nr;
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}
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return(r);
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}
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/*===========================================================================*
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* new_node *
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*===========================================================================*/
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static struct vnode *new_node(struct lookup *resolve, int oflags, mode_t bits)
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{
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/* Try to create a new inode and return a pointer to it. If the inode already
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exists, return a pointer to it as well, but set err_code accordingly.
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NULL is returned if the path cannot be resolved up to the last
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directory, or when the inode cannot be created due to permissions or
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otherwise. */
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struct vnode *dirp, *vp;
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struct vmnt *dir_vmp, *vp_vmp;
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int r;
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struct node_details res;
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struct lookup findnode;
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char *path;
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path = resolve->l_path; /* For easy access */
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lookup_init(&findnode, path, resolve->l_flags, &dir_vmp, &dirp);
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findnode.l_vmnt_lock = VMNT_WRITE;
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findnode.l_vnode_lock = VNODE_WRITE; /* dir node */
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/* When O_CREAT and O_EXCL flags are set, the path may not be named by a
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* symbolic link. */
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if (oflags & O_EXCL) findnode.l_flags |= PATH_RET_SYMLINK;
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/* See if the path can be opened down to the last directory. */
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if ((dirp = last_dir(&findnode, fp)) == NULL) return(NULL);
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/* The final directory is accessible. Get final component of the path. */
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lookup_init(&findnode, findnode.l_path, findnode.l_flags, &vp_vmp, &vp);
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findnode.l_vmnt_lock = VMNT_WRITE;
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findnode.l_vnode_lock = (oflags & O_TRUNC) ? VNODE_WRITE : VNODE_OPCL;
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vp = advance(dirp, &findnode, fp);
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assert(vp_vmp == NULL); /* Lookup to last dir should have yielded lock
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* on vmp or final component does not exist.
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* Either way, vp_vmp ought to be not set.
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*/
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/* The combination of a symlink with absolute path followed by a danglink
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* symlink results in a new path that needs to be re-resolved entirely. */
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if (path[0] == '/') {
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unlock_vnode(dirp);
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unlock_vmnt(dir_vmp);
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put_vnode(dirp);
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if (vp != NULL) {
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unlock_vnode(vp);
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put_vnode(vp);
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}
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return new_node(resolve, oflags, bits);
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}
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if (vp == NULL && err_code == ENOENT) {
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/* Last path component does not exist. Make a new directory entry. */
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if ((vp = get_free_vnode()) == NULL) {
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/* Can't create new entry: out of vnodes. */
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unlock_vnode(dirp);
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unlock_vmnt(dir_vmp);
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put_vnode(dirp);
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return(NULL);
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}
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lock_vnode(vp, VNODE_OPCL);
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upgrade_vmnt_lock(dir_vmp); /* Creating file, need exclusive access */
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if ((r = forbidden(fp, dirp, W_BIT|X_BIT)) != OK ||
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(r = req_create(dirp->v_fs_e, dirp->v_inode_nr,bits, fp->fp_effuid,
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fp->fp_effgid, path, &res)) != OK ) {
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/* Can't create inode either due to permissions or some other
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* problem. In case r is EEXIST, we might be dealing with a
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* dangling symlink.*/
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/* Downgrade lock to prevent deadlock during symlink resolving*/
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downgrade_vmnt_lock(dir_vmp);
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if (r == EEXIST) {
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struct vnode *slp, *old_wd;
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/* Resolve path up to symlink */
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findnode.l_flags = PATH_RET_SYMLINK;
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findnode.l_vnode_lock = VNODE_READ;
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findnode.l_vnode = &slp;
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slp = advance(dirp, &findnode, fp);
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if (slp != NULL) {
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if (S_ISLNK(slp->v_mode)) {
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/* Get contents of link */
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r = req_rdlink(slp->v_fs_e,
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slp->v_inode_nr,
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VFS_PROC_NR,
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(vir_bytes) path,
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PATH_MAX - 1, 0);
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if (r < 0) {
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/* Failed to read link */
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unlock_vnode(slp);
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unlock_vnode(dirp);
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unlock_vmnt(dir_vmp);
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put_vnode(slp);
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put_vnode(dirp);
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err_code = r;
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return(NULL);
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}
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path[r] = '\0'; /* Terminate path */
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}
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unlock_vnode(slp);
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put_vnode(slp);
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}
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/* Try to create the inode the dangling symlink was
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* pointing to. We have to use dirp as starting point
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* as there might be multiple successive symlinks
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* crossing multiple mountpoints.
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* Unlock vnodes and vmnts as we're going to recurse.
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*/
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unlock_vnode(dirp);
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unlock_vnode(vp);
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unlock_vmnt(dir_vmp);
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old_wd = fp->fp_wd; /* Save orig. working dirp */
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fp->fp_wd = dirp;
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vp = new_node(resolve, oflags, bits);
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fp->fp_wd = old_wd; /* Restore */
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if (vp != NULL) {
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put_vnode(dirp);
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*(resolve->l_vnode) = vp;
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return(vp);
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}
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r = err_code;
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}
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if (r == EEXIST)
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err_code = EIO; /* Impossible, we have verified that
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* the last component doesn't exist and
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* is not a dangling symlink. */
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else
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err_code = r;
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unlock_vmnt(dir_vmp);
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unlock_vnode(dirp);
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unlock_vnode(vp);
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put_vnode(dirp);
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return(NULL);
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}
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/* Store results and mark vnode in use */
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vp->v_fs_e = res.fs_e;
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vp->v_inode_nr = res.inode_nr;
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vp->v_mode = res.fmode;
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vp->v_size = res.fsize;
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vp->v_uid = res.uid;
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vp->v_gid = res.gid;
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vp->v_sdev = res.dev;
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vp->v_vmnt = dirp->v_vmnt;
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vp->v_dev = vp->v_vmnt->m_dev;
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vp->v_fs_count = 1;
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vp->v_ref_count = 1;
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} else {
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/* Either last component exists, or there is some other problem. */
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if (vp != NULL) {
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r = EEXIST; /* File exists or a symlink names a file while
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* O_EXCL is set. */
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} else
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r = err_code; /* Other problem. */
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}
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err_code = r;
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/* When dirp equals vp, we shouldn't release the lock as a vp is locked only
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* once. Releasing the lock would cause the resulting vp not be locked and
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* cause mayhem later on. */
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if (dirp != vp) {
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unlock_vnode(dirp);
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}
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unlock_vmnt(dir_vmp);
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put_vnode(dirp);
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*(resolve->l_vnode) = vp;
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return(vp);
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}
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|
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/*===========================================================================*
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* pipe_open *
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*===========================================================================*/
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static int pipe_open(struct vnode *vp, mode_t bits, int oflags)
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|
{
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|
/* This function is called from common_open. It checks if
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* there is at least one reader/writer pair for the pipe, if not
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* it suspends the caller, otherwise it revives all other blocked
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* processes hanging on the pipe.
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*/
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if ((bits & (R_BIT|W_BIT)) == (R_BIT|W_BIT)) return(ENXIO);
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/* Find the reader/writer at the other end of the pipe */
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if (find_filp(vp, bits & W_BIT ? R_BIT : W_BIT) == NULL) {
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/* Not found */
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if (oflags & O_NONBLOCK) {
|
|
if (bits & W_BIT) return(ENXIO);
|
|
} else {
|
|
/* Let's wait for the other side to show up */
|
|
suspend(FP_BLOCKED_ON_POPEN);
|
|
return(SUSPEND);
|
|
}
|
|
} else if (susp_count > 0) { /* revive blocked processes */
|
|
release(vp, VFS_OPEN, susp_count);
|
|
}
|
|
return(OK);
|
|
}
|
|
|
|
|
|
/*===========================================================================*
|
|
* do_mknod *
|
|
*===========================================================================*/
|
|
int do_mknod(void)
|
|
{
|
|
/* Perform the mknod(name, mode, addr) system call. */
|
|
register mode_t bits, mode_bits;
|
|
int r;
|
|
struct vnode *vp;
|
|
struct vmnt *vmp;
|
|
char fullpath[PATH_MAX];
|
|
struct lookup resolve;
|
|
vir_bytes vname1;
|
|
size_t vname1_length;
|
|
dev_t dev;
|
|
|
|
vname1 = (vir_bytes) job_m_in.VFS_MKNOD_NAME;
|
|
vname1_length = (size_t) job_m_in.VFS_MKNOD_LEN;
|
|
mode_bits = (mode_t) job_m_in.VFS_MKNOD_MODE;
|
|
dev = job_m_in.VFS_MKNOD_DEV;
|
|
|
|
lookup_init(&resolve, fullpath, PATH_NOFLAGS, &vmp, &vp);
|
|
resolve.l_vmnt_lock = VMNT_WRITE;
|
|
resolve.l_vnode_lock = VNODE_WRITE;
|
|
|
|
/* Only the super_user may make nodes other than fifos. */
|
|
if (!super_user && (!S_ISFIFO(mode_bits) && !S_ISSOCK(mode_bits))) {
|
|
return(EPERM);
|
|
}
|
|
bits = (mode_bits & S_IFMT) | (mode_bits & ACCESSPERMS & fp->fp_umask);
|
|
|
|
/* Open directory that's going to hold the new node. */
|
|
if (fetch_name(vname1, vname1_length, fullpath) != OK) return(err_code);
|
|
if ((vp = last_dir(&resolve, fp)) == NULL) return(err_code);
|
|
|
|
/* Make sure that the object is a directory */
|
|
if (!S_ISDIR(vp->v_mode)) {
|
|
r = ENOTDIR;
|
|
} else if ((r = forbidden(fp, vp, W_BIT|X_BIT)) == OK) {
|
|
r = req_mknod(vp->v_fs_e, vp->v_inode_nr, fullpath, fp->fp_effuid,
|
|
fp->fp_effgid, bits, dev);
|
|
}
|
|
|
|
unlock_vnode(vp);
|
|
unlock_vmnt(vmp);
|
|
put_vnode(vp);
|
|
return(r);
|
|
}
|
|
|
|
/*===========================================================================*
|
|
* do_mkdir *
|
|
*===========================================================================*/
|
|
int do_mkdir(void)
|
|
{
|
|
/* Perform the mkdir(name, mode) system call. */
|
|
mode_t bits; /* mode bits for the new inode */
|
|
int r;
|
|
struct vnode *vp;
|
|
struct vmnt *vmp;
|
|
char fullpath[PATH_MAX];
|
|
struct lookup resolve;
|
|
mode_t dirmode;
|
|
|
|
if (copy_path(fullpath, sizeof(fullpath)) != OK)
|
|
return(err_code);
|
|
dirmode = (mode_t) job_m_in.VFS_PATH_MODE;
|
|
|
|
lookup_init(&resolve, fullpath, PATH_NOFLAGS, &vmp, &vp);
|
|
resolve.l_vmnt_lock = VMNT_WRITE;
|
|
resolve.l_vnode_lock = VNODE_WRITE;
|
|
|
|
bits = I_DIRECTORY | (dirmode & RWX_MODES & fp->fp_umask);
|
|
if ((vp = last_dir(&resolve, fp)) == NULL) return(err_code);
|
|
|
|
/* Make sure that the object is a directory */
|
|
if (!S_ISDIR(vp->v_mode)) {
|
|
r = ENOTDIR;
|
|
} else if ((r = forbidden(fp, vp, W_BIT|X_BIT)) == OK) {
|
|
r = req_mkdir(vp->v_fs_e, vp->v_inode_nr, fullpath, fp->fp_effuid,
|
|
fp->fp_effgid, bits);
|
|
}
|
|
|
|
unlock_vnode(vp);
|
|
unlock_vmnt(vmp);
|
|
put_vnode(vp);
|
|
return(r);
|
|
}
|
|
|
|
/*===========================================================================*
|
|
* actual_lseek *
|
|
*===========================================================================*/
|
|
int actual_lseek(struct fproc *rfp, int seekfd, int seekwhence, off_t offset,
|
|
off_t *newposp)
|
|
{
|
|
register struct filp *rfilp;
|
|
int r = OK;
|
|
off_t pos, newpos;
|
|
|
|
/* Check to see if the file descriptor is valid. */
|
|
if ( (rfilp = get_filp2(rfp, seekfd, VNODE_READ)) == NULL) {
|
|
return(err_code);
|
|
}
|
|
|
|
/* No lseek on pipes. */
|
|
if (S_ISFIFO(rfilp->filp_vno->v_mode)) {
|
|
unlock_filp(rfilp);
|
|
return(ESPIPE);
|
|
}
|
|
|
|
/* The value of 'whence' determines the start position to use. */
|
|
switch(seekwhence) {
|
|
case SEEK_SET: pos = 0; break;
|
|
case SEEK_CUR: pos = rfilp->filp_pos; break;
|
|
case SEEK_END: pos = rfilp->filp_vno->v_size; break;
|
|
default: unlock_filp(rfilp); return(EINVAL);
|
|
}
|
|
|
|
newpos = pos + offset;
|
|
|
|
/* Check for overflow. */
|
|
if ((offset > 0) && (newpos <= pos)) {
|
|
r = EOVERFLOW;
|
|
} else if ((offset < 0) && (newpos >= pos)) {
|
|
r = EOVERFLOW;
|
|
} else {
|
|
if (newposp != NULL) *newposp = newpos;
|
|
|
|
if (newpos != rfilp->filp_pos) {
|
|
rfilp->filp_pos = newpos;
|
|
|
|
/* Inhibit read ahead request */
|
|
r = req_inhibread(rfilp->filp_vno->v_fs_e,
|
|
rfilp->filp_vno->v_inode_nr);
|
|
}
|
|
}
|
|
|
|
unlock_filp(rfilp);
|
|
return(r);
|
|
}
|
|
|
|
/*===========================================================================*
|
|
* do_lseek *
|
|
*===========================================================================*/
|
|
int do_lseek(void)
|
|
{
|
|
/* Perform the lseek(2) system call. */
|
|
off_t newpos;
|
|
int r;
|
|
|
|
if ((r = actual_lseek(fp, job_m_in.VFS_LSEEK_FD,
|
|
job_m_in.VFS_LSEEK_WHENCE, make64(job_m_in.VFS_LSEEK_OFF_LO,
|
|
job_m_in.VFS_LSEEK_OFF_HI), &newpos)) != OK)
|
|
return r;
|
|
|
|
/* insert the new position into the output message */
|
|
job_m_out.VFS_LSEEK_OFF_LO = ex64lo(newpos);
|
|
job_m_out.VFS_LSEEK_OFF_HI = ex64hi(newpos);
|
|
return OK;
|
|
}
|
|
|
|
/*===========================================================================*
|
|
* do_close *
|
|
*===========================================================================*/
|
|
int do_close(void)
|
|
{
|
|
/* Perform the close(fd) system call. */
|
|
int thefd = job_m_in.VFS_CLOSE_FD;
|
|
return close_fd(fp, thefd);
|
|
}
|
|
|
|
|
|
/*===========================================================================*
|
|
* close_fd *
|
|
*===========================================================================*/
|
|
int close_fd(rfp, fd_nr)
|
|
struct fproc *rfp;
|
|
int fd_nr;
|
|
{
|
|
/* Perform the close(fd) system call. */
|
|
register struct filp *rfilp;
|
|
register struct vnode *vp;
|
|
struct file_lock *flp;
|
|
int lock_count;
|
|
|
|
/* First locate the vnode that belongs to the file descriptor. */
|
|
if ( (rfilp = get_filp2(rfp, fd_nr, VNODE_OPCL)) == NULL) return(err_code);
|
|
|
|
vp = rfilp->filp_vno;
|
|
|
|
/* first, make all future get_filp2()'s fail; otherwise
|
|
* we might try to close the same fd in different threads
|
|
*/
|
|
rfp->fp_filp[fd_nr] = NULL;
|
|
|
|
close_filp(rfilp);
|
|
|
|
FD_CLR(fd_nr, &rfp->fp_cloexec_set);
|
|
|
|
/* Check to see if the file is locked. If so, release all locks. */
|
|
if (nr_locks > 0) {
|
|
lock_count = nr_locks; /* save count of locks */
|
|
for (flp = &file_lock[0]; flp < &file_lock[NR_LOCKS]; flp++) {
|
|
if (flp->lock_type == 0) continue; /* slot not in use */
|
|
if (flp->lock_vnode == vp && flp->lock_pid == rfp->fp_pid) {
|
|
flp->lock_type = 0;
|
|
nr_locks--;
|
|
}
|
|
}
|
|
if (nr_locks < lock_count)
|
|
lock_revive(); /* one or more locks released */
|
|
}
|
|
|
|
return(OK);
|
|
}
|