ref: f0f2d452c873255dec4b3359b3f93e349be0f2c5
dir: /sys/src/cmd/cp.c/
#include <u.h> #include <libc.h> int buflen; int failed; int gflag; int uflag; int xflag; void copy(char *from, char *to, int todir); int copy1(int fdf, int fdt, char *from, char *to); void main(int argc, char *argv[]) { Dir *dirb; int todir, i; ARGBEGIN { case 'g': gflag++; break; case 'u': uflag++; gflag++; break; case 'x': xflag++; break; default: goto usage; } ARGEND todir=0; if(argc < 2) goto usage; dirb = dirstat(argv[argc-1]); if(dirb!=nil && (dirb->mode&DMDIR)) todir=1; if(argc>2 && !todir){ fprint(2, "cp: %s not a directory\n", argv[argc-1]); exits("bad usage"); } for(i=0; i<argc-1; i++) copy(argv[i], argv[argc-1], todir); if(failed) exits("errors"); exits(0); usage: fprint(2, "usage:\tcp [-gux] fromfile tofile\n"); fprint(2, "\tcp [-x] fromfile ... todir\n"); exits("usage"); } int samefile(Dir *a, char *an, char *bn) { Dir *b; int ret; ret = 0; b=dirstat(bn); if(b != nil) if(b->qid.type==a->qid.type) if(b->qid.path==a->qid.path) if(b->qid.vers==a->qid.vers) if(b->dev==a->dev) if(b->type==a->type){ fprint(2, "cp: %s and %s are the same file\n", an, bn); ret = 1; } free(b); return ret; } void copy(char *from, char *to, int todir) { Dir *dirb, dirt; char *name; int fdf, fdt, fds, mode; name = nil; if(todir){ char *s, *elem; elem=s=from; while(*s++) if(s[-1]=='/') elem=s; name = smprint("%s/%s", to, elem); to = name; } fdf = fdt = fds = -1; if((dirb=dirstat(from))==nil){ fprint(2,"cp: can't stat %s: %r\n", from); failed = 1; goto out; } mode = dirb->mode; if(mode&DMDIR){ fprint(2, "cp: %s is a directory\n", from); failed = 1; goto out; } if(samefile(dirb, from, to)){ failed = 1; goto out; } mode &= 0777; fdf=open(from, OREAD); if(fdf<0){ fprint(2, "cp: can't open %s: %r\n", from); failed = 1; goto out; } fdt=create(to, OWRITE, mode); if(fdt<0){ fprint(2, "cp: can't create %s: %r\n", to); failed = 1; goto out; } buflen = iounit(fdf); if(buflen <= 0) buflen = IOUNIT; if(copy1(fdf, fds < 0 ? fdt : fds, from, to)==0){ if(fds >= 0 && write(fds, "", 0) < 0){ fprint(2, "cp: error writing %s: %r\n", to); failed = 1; goto out; } if(xflag || gflag || uflag){ nulldir(&dirt); if(xflag){ dirt.mtime = dirb->mtime; dirt.mode = dirb->mode; } if(uflag) dirt.uid = dirb->uid; if(gflag) dirt.gid = dirb->gid; if(dirfwstat(fdt, &dirt) < 0) fprint(2, "cp: warning: can't wstat %s: %r\n", to); } } out: if(fdf >= 0) close(fdf); if(fdt >= 0) close(fdt); if(fds >= 0) close(fds); free(dirb); free(name); } int copy1(int fdf, int fdt, char *from, char *to) { char *buf; long n, n1, rcount; int rv; char err[ERRMAX]; buf = malloc(buflen); if(buf == nil){ fprint(2, "cp: out of memory\n"); return -1; } /* clear any residual error */ err[0] = '\0'; errstr(err, ERRMAX); rv = 0; for(rcount=0;; rcount++) { n = read(fdf, buf, buflen); if(n <= 0) break; n1 = write(fdt, buf, n); if(n1 != n) { fprint(2, "cp: error writing %s: %r\n", to); failed = 1; rv = -1; break; } } if(n < 0) { fprint(2, "cp: error reading %s: %r\n", from); failed = 1; rv = -1; } free(buf); return rv; }