1 /***********************************************************************
2 * *
3 * This software is part of the ast package *
4 * Copyright (c) 1985-2011 AT&T Intellectual Property *
5 * and is licensed under the *
6 * Eclipse Public License, Version 1.0 *
7 * by AT&T Intellectual Property *
8 * *
9 * A copy of the License is available at *
10 * http://www.eclipse.org/org/documents/epl-v10.html *
11 * (with md5 checksum b35adb5213ca9657e911e9befb180842) *
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
astcopy(int rfd,int wfd,off_t n)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