1*0Sstevel@tonic-gate /*- 2*0Sstevel@tonic-gate * See the file LICENSE for redistribution information. 3*0Sstevel@tonic-gate * 4*0Sstevel@tonic-gate * Copyright (c) 1997, 1998 5*0Sstevel@tonic-gate * Sleepycat Software. All rights reserved. 6*0Sstevel@tonic-gate */ 7*0Sstevel@tonic-gate 8*0Sstevel@tonic-gate #include "config.h" 9*0Sstevel@tonic-gate 10*0Sstevel@tonic-gate #ifndef lint 11*0Sstevel@tonic-gate static const char sccsid[] = "@(#)os_seek.c 10.11 (Sleepycat) 10/12/98"; 12*0Sstevel@tonic-gate #endif /* not lint */ 13*0Sstevel@tonic-gate 14*0Sstevel@tonic-gate #ifndef NO_SYSTEM_INCLUDES 15*0Sstevel@tonic-gate #include <sys/types.h> 16*0Sstevel@tonic-gate 17*0Sstevel@tonic-gate #include <errno.h> 18*0Sstevel@tonic-gate #include <unistd.h> 19*0Sstevel@tonic-gate #endif 20*0Sstevel@tonic-gate 21*0Sstevel@tonic-gate #include "db_int.h" 22*0Sstevel@tonic-gate #include "os_jump.h" 23*0Sstevel@tonic-gate 24*0Sstevel@tonic-gate /* 25*0Sstevel@tonic-gate * __os_seek -- 26*0Sstevel@tonic-gate * Seek to a page/byte offset in the file. 27*0Sstevel@tonic-gate * 28*0Sstevel@tonic-gate * PUBLIC: int __os_seek __P((int, size_t, db_pgno_t, u_int32_t, int, int)); 29*0Sstevel@tonic-gate */ 30*0Sstevel@tonic-gate int 31*0Sstevel@tonic-gate __os_seek(fd, pgsize, pageno, relative, isrewind, whence) 32*0Sstevel@tonic-gate int fd; 33*0Sstevel@tonic-gate size_t pgsize; 34*0Sstevel@tonic-gate db_pgno_t pageno; 35*0Sstevel@tonic-gate u_int32_t relative; 36*0Sstevel@tonic-gate int isrewind, whence; 37*0Sstevel@tonic-gate { 38*0Sstevel@tonic-gate off_t offset; 39*0Sstevel@tonic-gate int ret; 40*0Sstevel@tonic-gate 41*0Sstevel@tonic-gate if (__db_jump.j_seek != NULL) 42*0Sstevel@tonic-gate ret = __db_jump.j_seek(fd, 43*0Sstevel@tonic-gate pgsize, pageno, relative, isrewind, whence); 44*0Sstevel@tonic-gate else { 45*0Sstevel@tonic-gate offset = (off_t)pgsize * pageno + relative; 46*0Sstevel@tonic-gate if (isrewind) 47*0Sstevel@tonic-gate offset = -offset; 48*0Sstevel@tonic-gate 49*0Sstevel@tonic-gate ret = lseek(fd, offset, whence); 50*0Sstevel@tonic-gate } 51*0Sstevel@tonic-gate return (ret == -1 ? errno : 0); 52*0Sstevel@tonic-gate } 53