/* * cp oldfile newfile */ #define BSIZE 512 #include <stdio.h> #include <sys/types.h> #include <sys/stat.h> struct stat stbuf1, stbuf2; char iobuf[BSIZE]; main(argc, argv) char *argv[]; { register i, r; if (argc < 3) goto usage; if (argc > 3) { if (stat(argv[argc-1], &stbuf2) < 0) goto usage; if ((stbuf2.st_mode&S_IFMT) != S_IFDIR) goto usage; } r = 0; for(i=1; i<argc-1;i++) r |= copy(argv[i], argv[argc-1]); exit(r); usage: fprintf(stderr, "Usage: cp: f1 f2; or cp f1 ... fn d2\n"); exit(1); } copy(from, to) char *from, *to; { int fold, fnew, n; register char *p1, *p2, *bp; int mode; if ((fold = open(from, 0)) < 0) { fprintf(stderr, "cp: cannot open %s\n", from); return(1); } fstat(fold, &stbuf1); mode = stbuf1.st_mode; /* is target a directory? */ if (stat(to, &stbuf2) >=0 && (stbuf2.st_mode&S_IFMT) == S_IFDIR) { p1 = from; p2 = to; bp = iobuf; while(*bp++ = *p2++) ; bp[-1] = '/'; p2 = bp; while(*bp = *p1++) if (*bp++ == '/') bp = p2; to = iobuf; } if (stat(to, &stbuf2) >= 0) { if (stbuf1.st_dev == stbuf2.st_dev && stbuf1.st_ino == stbuf2.st_ino) { fprintf(stderr, "cp: cannot copy file to itself.\n"); return(1); } } if ((fnew = creat(to, mode)) < 0) { fprintf(stderr, "cp: cannot create %s\n", to); close(fold); return(1); } while(n = read(fold, iobuf, BSIZE)) { if (n < 0) { fprintf(stderr, "cp: read error\n"); close(fold); close(fnew); return(1); } else if (write(fnew, iobuf, n) != n) { fprintf(stderr, "cp: write error.\n"); close(fold); close(fnew); return(1); } } close(fold); close(fnew); return(0); }