| // SPDX-License-Identifier: GPL-2.0 |
| /* |
| * Copyright (c) 2000 Silicon Graphics, Inc. |
| * All Rights Reserved. |
| */ |
| #include <sys/types.h> |
| #include <sys/stat.h> |
| #include <sys/file.h> |
| #include <sys/param.h> |
| #include <fcntl.h> |
| #include <unistd.h> |
| #include <stdio.h> |
| #include <errno.h> |
| #include <sys/sysmacros.h> |
| #include <string.h> /* memset, strerror */ |
| #include "file_lock.h" |
| |
| |
| #ifndef EFSEXCLWR |
| #define EFSEXCLWR 503 |
| #endif |
| |
| /* |
| * String containing the last system call. |
| * |
| */ |
| char Fl_syscall_str[128]; |
| |
| static char errmsg[256]; |
| |
| /*********************************************************************** |
| * |
| * Test interface to the fcntl system call. |
| * It will loop if the LOCK_NB flags is NOT set. |
| ***********************************************************************/ |
| int |
| file_lock(fd, flags, errormsg) |
| int fd; |
| int flags; |
| char **errormsg; |
| { |
| register int cmd, ret; |
| struct flock flocks; |
| |
| memset(&flocks, 0, sizeof(struct flock)); |
| |
| if (flags&LOCK_NB) |
| cmd = F_SETLK; |
| else |
| cmd = F_SETLKW; |
| |
| flocks.l_whence = 0; |
| flocks.l_start = 0; |
| flocks.l_len = 0; |
| |
| if (flags&LOCK_UN) |
| flocks.l_type = F_UNLCK; |
| else if (flags&LOCK_EX) |
| flocks.l_type = F_WRLCK; |
| else if (flags&LOCK_SH) |
| flocks.l_type = F_RDLCK; |
| else { |
| errno = EINVAL; |
| if ( errormsg != NULL ) { |
| sprintf(errmsg, |
| "Programmer error, called file_lock with in valid flags\n"); |
| *errormsg = errmsg; |
| } |
| return -1; |
| } |
| |
| sprintf(Fl_syscall_str, |
| "fcntl(%d, %d, &flocks): type:%d whence:%d, start:%lld len:%lld\n", |
| fd, cmd, flocks.l_type, flocks.l_whence, |
| (long long)flocks.l_start, (long long)flocks.l_len); |
| |
| while (1) { |
| ret = fcntl(fd, cmd, &flocks); |
| |
| if ( ret < 0 ) { |
| if ( cmd == F_SETLK ) |
| switch (errno) { |
| /* these errors are okay */ |
| case EACCES: /* Permission denied */ |
| case EINTR: /* interrupted system call */ |
| #ifdef EFILESH |
| case EFILESH: /* file shared */ |
| #endif |
| case EFSEXCLWR: /* File is write protected */ |
| continue; /* retry getting lock */ |
| } |
| if ( errormsg != NULL ) { |
| sprintf(errmsg, "fcntl(%d, %d, &flocks): errno:%d %s\n", |
| fd, cmd, errno, strerror(errno)); |
| *errormsg = errmsg; |
| } |
| return -1; |
| } |
| break; |
| } |
| |
| return ret; |
| |
| } /* end of file_lock */ |
| |
| /*********************************************************************** |
| * |
| * Test interface to the fcntl system call. |
| * It will loop if the LOCK_NB flags is NOT set. |
| ***********************************************************************/ |
| int |
| record_lock(fd, flags, start, len, errormsg) |
| int fd; |
| int flags; |
| int start; |
| int len; |
| char **errormsg; |
| { |
| register int cmd, ret; |
| struct flock flocks; |
| |
| memset(&flocks, 0, sizeof(struct flock)); |
| |
| if (flags&LOCK_NB) |
| cmd = F_SETLK; |
| else |
| cmd = F_SETLKW; |
| |
| flocks.l_whence = 0; |
| flocks.l_start = start; |
| flocks.l_len = len; |
| |
| if (flags&LOCK_UN) |
| flocks.l_type = F_UNLCK; |
| else if (flags&LOCK_EX) |
| flocks.l_type = F_WRLCK; |
| else if (flags&LOCK_SH) |
| flocks.l_type = F_RDLCK; |
| else { |
| errno = EINVAL; |
| if ( errormsg != NULL ) { |
| sprintf(errmsg, |
| "Programmer error, called record_lock with in valid flags\n"); |
| *errormsg = errmsg; |
| } |
| return -1; |
| } |
| |
| sprintf(Fl_syscall_str, |
| "fcntl(%d, %d, &flocks): type:%d whence:%d, start:%lld len:%lld\n", |
| fd, cmd, flocks.l_type, flocks.l_whence, |
| (long long)flocks.l_start, (long long)flocks.l_len); |
| |
| while (1) { |
| ret = fcntl(fd, cmd, &flocks); |
| |
| if ( ret < 0 ) { |
| if ( cmd == F_SETLK ) |
| switch (errno) { |
| /* these errors are okay */ |
| case EACCES: /* Permission denied */ |
| case EINTR: /* interrupted system call */ |
| #ifdef EFILESH |
| case EFILESH: /* file shared */ |
| #endif |
| case EFSEXCLWR: /* File is write protected */ |
| continue; /* retry getting lock */ |
| } |
| if ( errormsg != NULL ) { |
| sprintf(errmsg, "fcntl(%d, %d, &flocks): errno:%d %s\n", |
| fd, cmd, errno, strerror(errno)); |
| *errormsg = errmsg; |
| } |
| return -1; |
| } |
| break; |
| } |
| |
| return ret; |
| |
| } /* end of record_lock */ |
| |
| |