diff options
| -rw-r--r-- | toys/posix/cp.c | 163 |
1 files changed, 89 insertions, 74 deletions
diff --git a/toys/posix/cp.c b/toys/posix/cp.c index 01ba385c..d9a0d29c 100644 --- a/toys/posix/cp.c +++ b/toys/posix/cp.c @@ -53,7 +53,7 @@ GLOBALS( int cp_node(struct dirtree *try) { - int fdout, cfd = try->parent ? try->parent->extra : AT_FDCWD, + int fdout = -1, cfd = try->parent ? try->parent->extra : AT_FDCWD, tfd = dirtree_parentfd(try); unsigned flags = toys.optflags; char *catch = try->parent ? try->name : TT.destname, *err = "%s"; @@ -65,87 +65,102 @@ int cp_node(struct dirtree *try) if (S_ISDIR(try->st.st_mode) && try->data == -1) { fdout = try->extra; err = 0; - goto dashp; - } + } else { - // -d is only the same as -r for symlinks, not for directories - if (S_ISLNK(try->st.st_mode) & (flags & FLAG_d)) flags |= FLAG_r; - - // Detect recursive copies via repeated top node (cp -R .. .) or - // identical source/target (fun with hardlinks). - if ((TT.top.st_dev == try->st.st_dev && TT.top.st_ino == try->st.st_ino - && (catch = TT.destname)) - || (!fstatat(cfd, catch, &cst, 0) && cst.st_dev == try->st.st_dev - && cst.st_ino == try->st.st_ino)) - { - char *s = dirtree_path(try, 0); - error_msg("'%s' is '%s'", catch, s); - free(s); - - return 0; - } + // -d is only the same as -r for symlinks, not for directories + if (S_ISLNK(try->st.st_mode) & (flags & FLAG_d)) flags |= FLAG_r; - // Handle -inv + // Detect recursive copies via repeated top node (cp -R .. .) or + // identical source/target (fun with hardlinks). + if ((TT.top.st_dev == try->st.st_dev && TT.top.st_ino == try->st.st_ino + && (catch = TT.destname)) + || (!fstatat(cfd, catch, &cst, 0) && cst.st_dev == try->st.st_dev + && cst.st_ino == try->st.st_ino)) + { + error_msg("'%s' is '%s'", catch, err = dirtree_path(try, 0)); + free(err); - if ((flags & (FLAG_i|FLAG_n)) && !faccessat(cfd, catch, R_OK, 0)) - if ((flags & FLAG_n) || !yesno("cp: overwrite", 1)) return 0; + return 0; + } - if (flags & FLAG_v) { - char *s = dirtree_path(try, 0); - printf("cp '%s'\n", s); - free(s); - } + // Handle -inv - // Copy directory or file to destination. - - if (S_ISDIR(try->st.st_mode)) { - struct stat st2; - - if (!(flags & (FLAG_a|FLAG_r|FLAG_R))) { - err = "Skipped dir '%s'"; - catch = try->name; - - // Always make directory writeable to us, so we can create files in it. - // - // Yes, there's a race window between mkdir() and open() so it's - // possible that -p can be made to chown a directory other than the one - // we created. The closest we can do to closing this is make sure - // that what we open _is_ a directory rather than something else. - - } else if ((mkdirat(cfd, catch, try->st.st_mode | 0200) && errno != EEXIST) - || 0>(try->extra = openat(cfd, catch, 0)) || fstat(try->extra, &st2) - || !S_ISDIR(st2.st_mode)); - else return DIRTREE_COMEAGAIN; - } else if (flags & FLAG_l) { - if (!linkat(tfd, try->name, cfd, catch, 0)) err = 0; - } else if ((try->parent || (flags & (FLAG_a|FLAG_r))) - && !S_ISREG(try->st.st_mode)) - { - if (S_ISLNK(try->st.st_mode)) { - int i = readlinkat(tfd, try->name, toybuf, sizeof(toybuf)); - if (i > 0 && i < sizeof(toybuf) && !symlinkat(toybuf, cfd, catch)) - err = 0; - } else if (!mknodat(cfd, catch, try->st.st_mode, try->st.st_dev)) err = 0; - } else { - int fdin, i; + if ((flags & (FLAG_i|FLAG_n)) && !faccessat(cfd, catch, R_OK, 0)) + if ((flags & FLAG_n) || !yesno("cp: overwrite", 1)) return 0; - fdin = openat(tfd, try->name, O_RDONLY); - if (fdin < 0) catch = try->name; - else { - for (i=2 ; i; i--) { - fdout = openat(cfd, catch, O_RDWR|O_CREAT|O_TRUNC, try->st.st_mode); - if (fdout>=0 || !(flags & FLAG_f)) break; - unlinkat(cfd, catch, 0); - } - if (fdout >= 0) { - xsendfile(fdin, fdout); - err = 0; - } - close(fdin); + if (flags & FLAG_v) { + char *s = dirtree_path(try, 0); + printf("cp '%s'\n", s); + free(s); } -dashp: - if (!(flags & FLAG_l) && (flags & (FLAG_a|FLAG_p))) { + // Loop for -f retry after unlink + do { + + // Copy directory + + if (S_ISDIR(try->st.st_mode)) { + struct stat st2; + + if (!(flags & (FLAG_a|FLAG_r|FLAG_R))) { + err = "Skipped dir '%s'"; + catch = try->name; + break; + } + + // Always make directory writeable to us, so we can create files in it. + // + // Yes, there's a race window between mkdir() and open() so it's + // possible that -p can be made to chown a directory other than the one + // we created. The closest we can do to closing this is make sure + // that what we open _is_ a directory rather than something else. + + if (!mkdirat(cfd, catch, try->st.st_mode | 0200) || errno == EEXIST) + if (-1 != (try->extra = openat(cfd, catch, 0))) + if (!fstat(try->extra, &st2)) + if (S_ISDIR(st2.st_mode)) return DIRTREE_COMEAGAIN; + + // Hardlink + + } else if (flags & FLAG_l) { + if (!linkat(tfd, try->name, cfd, catch, 0)) err = 0; + + // Do something _other_ than copy contents of a file? + } else if (!S_ISREG(try->st.st_mode) + && (try->parent || (flags & (FLAG_a|FLAG_r)))) + { + // symlink + if (S_ISLNK(try->st.st_mode)) { + int i = readlinkat(tfd, try->name, toybuf, sizeof(toybuf)); + if (i < 1 || i >= sizeof(toybuf)) break; + else if (!symlinkat(toybuf, cfd, catch)) err = 0; + // block, char, fifo, socket + } else if (!mknodat(cfd, catch, try->st.st_mode, try->st.st_dev)) + if (!(flags & (FLAG_a|FLAG_p)) + || -1 != (fdout = openat(cfd, catch, O_RDONLY))) err = 0; + + // Copy contents of file. + } else { + int fdin; + + fdin = openat(tfd, try->name, O_RDONLY); + if (fdin < 0) { + catch = try->name; + break; + } else { + fdout = openat(cfd, catch, O_RDWR|O_CREAT|O_TRUNC, try->st.st_mode); + if (fdout >= 0) { + xsendfile(fdin, fdout); + err = 0; + } + close(fdin); + } + } + } while (err && (flags & FLAG_f) && !unlinkat(cfd, catch, 0)); + } + + if (fdout != -1) { + if (flags & (FLAG_a|FLAG_p)) { struct timespec times[2]; // Inability to set these isn't fatal, some require root access. |