1 /*********************************************************************** 2 * * 3 * This software is part of the ast package * 4 * Copyright (c) 1985-2007 AT&T Knowledge Ventures * 5 * and is licensed under the * 6 * Common Public License, Version 1.0 * 7 * by AT&T Knowledge Ventures * 8 * * 9 * A copy of the License is available at * 10 * http://www.opensource.org/licenses/cpl1.0.txt * 11 * (with md5 checksum 059e8cd6165cb4c31e351f2b69388fd9) * 12 * * 13 * Information and Software Systems Research * 14 * AT&T Research * 15 * Florham Park NJ * 16 * * 17 * Glenn Fowler <gsf@research.att.com> * 18 * David Korn <dgk@research.att.com> * 19 * Phong Vo <kpv@research.att.com> * 20 * * 21 ***********************************************************************/ 22 #pragma prototyped 23 /* 24 * Glenn Fowler 25 * AT&T Bell Laboratories 26 * 27 * copy from rfd to wfd (with conditional mmap hacks) 28 */ 29 30 #include <ast.h> 31 #include <ast_mmap.h> 32 33 #if _mmap_worthy > 1 34 35 #include <ls.h> 36 37 #define MAPSIZE (1024*256) 38 39 #endif 40 41 #undef BUFSIZ 42 #define BUFSIZ 4096 43 44 /* 45 * copy n bytes from rfd to wfd 46 * actual byte count returned 47 * if n<=0 then ``good'' size is used 48 */ 49 50 off_t 51 astcopy(int rfd, int wfd, off_t n) 52 { 53 register off_t c; 54 #ifdef MAPSIZE 55 off_t pos; 56 off_t mapsize; 57 char* mapbuf; 58 struct stat st; 59 #endif 60 61 static int bufsiz; 62 static char* buf; 63 64 if (n <= 0 || n >= BUFSIZ * 2) 65 { 66 #if MAPSIZE 67 if (!fstat(rfd, &st) && S_ISREG(st.st_mode) && (pos = lseek(rfd, (off_t)0, 1)) != ((off_t)-1)) 68 { 69 if (pos >= st.st_size) return(0); 70 mapsize = st.st_size - pos; 71 if (mapsize > MAPSIZE) mapsize = (mapsize > n && n > 0) ? n : MAPSIZE; 72 if (mapsize >= BUFSIZ * 2 && (mapbuf = (char*)mmap(NiL, mapsize, PROT_READ, MAP_SHARED, rfd, pos)) != ((caddr_t)-1)) 73 { 74 if (write(wfd, mapbuf, mapsize) != mapsize || lseek(rfd, mapsize, 1) == ((off_t)-1)) return(-1); 75 munmap((caddr_t)mapbuf, mapsize); 76 return(mapsize); 77 } 78 } 79 #endif 80 if (n <= 0) n = BUFSIZ; 81 } 82 if (n > bufsiz) 83 { 84 if (buf) free(buf); 85 bufsiz = roundof(n, BUFSIZ); 86 if (!(buf = newof(0, char, bufsiz, 0))) return(-1); 87 } 88 if ((c = read(rfd, buf, (size_t)n)) > 0 && write(wfd, buf, (size_t)c) != c) c = -1; 89 return(c); 90 } 91