Preserve the right errno value when trying adjunct functions during

robust backup, copy, and renaming activities.

backup.c

@@ -180,10 +180,19 @@ int make_bak_dir(const char *fullpath)
 /* robustly move a file, creating new directory structures if necessary */
 static int robust_move(const char *src, char *dst)
 {
-	if (robust_rename(src, dst, NULL, 0755) < 0
-	 && (errno != ENOENT || make_bak_dir(dst) < 0
-	  || robust_rename(src, dst, NULL, 0755) < 0))
-		return -1;
+	if (robust_rename(src, dst, NULL, 0755) < 0) {
+		int save_errno = errno ? errno : EINVAL; /* 0 paranoia */
+		if (errno == ENOENT && make_bak_dir(dst) == 0) {
+			if (robust_rename(src, dst, NULL, 0755) < 0)
+				save_errno = errno ? errno : save_errno;
+			else
+				save_errno = 0;
+		}
+		if (save_errno) {
+			errno = save_errno;
+			return -1;
+		}
+	}
 	return 0;
 }
 
@@ -237,11 +246,18 @@ static int keep_backup(const char *fname)
 		uint32 *devp = F_RDEV_P(file);
 		dev_t rdev = MAKEDEV(DEV_MAJOR(devp), DEV_MINOR(devp));
 		do_unlink(buf);
-		if (do_mknod(buf, file->mode, rdev) < 0
-		    && (errno != ENOENT || make_bak_dir(buf) < 0
-		     || do_mknod(buf, file->mode, rdev) < 0)) {
-			rsyserr(FERROR, errno, "mknod %s failed",
-				full_fname(buf));
+		if (do_mknod(buf, file->mode, rdev) < 0) {
+			int save_errno = errno ? errno : EINVAL; /* 0 paranoia */
+			if (errno == ENOENT && make_bak_dir(buf) == 0) {
+				if (do_mknod(buf, file->mode, rdev) < 0)
+					save_errno = errno ? errno : save_errno;
+				else
+					save_errno = 0;
+			}
+			if (save_errno) {
+				rsyserr(FERROR, save_errno, "mknod %s failed",
+					full_fname(buf));
+			}
 		} else if (verbose > 2) {
 			rprintf(FINFO, "make_backup: DEVICE %s successful.\n",
 				fname);
@@ -252,11 +268,18 @@ static int keep_backup(const char *fname)
 
 	if (!kept && S_ISDIR(file->mode)) {
 		/* make an empty directory */
-		if (do_mkdir(buf, file->mode) < 0
-		    && (errno != ENOENT || make_bak_dir(buf) < 0
-		     || do_mkdir(buf, file->mode) < 0)) {
-			rsyserr(FINFO, errno, "mkdir %s failed",
-				full_fname(buf));
+		if (do_mkdir(buf, file->mode) < 0) {
+			int save_errno = errno ? errno : EINVAL; /* 0 paranoia */
+			if (errno == ENOENT && make_bak_dir(buf) == 0) {
+				if (do_mkdir(buf, file->mode) < 0)
+					save_errno = errno ? errno : save_errno;
+				else
+					save_errno = 0;
+			}
+			if (save_errno) {
+				rsyserr(FINFO, save_errno, "mkdir %s failed",
+					full_fname(buf));
+			}
 		}
 
 		ret_code = do_rmdir(fname);
@@ -278,11 +301,18 @@ static int keep_backup(const char *fname)
 			kept = 1;
 		} else {
 			do_unlink(buf);
-			if (do_symlink(sl, buf) < 0
-			    && (errno != ENOENT || make_bak_dir(buf) < 0
-			     || do_symlink(sl, buf) < 0)) {
-				rsyserr(FERROR, errno, "link %s -> \"%s\"",
-					full_fname(buf), sl);
+			if (do_symlink(sl, buf) < 0) {
+				int save_errno = errno ? errno : EINVAL; /* 0 paranoia */
+				if (errno == ENOENT && make_bak_dir(buf) == 0) {
+					if (do_symlink(sl, buf) < 0)
+						save_errno = errno ? errno : save_errno;
+					else
+						save_errno = 0;
+				}
+				if (save_errno) {
+					rsyserr(FERROR, save_errno, "link %s -> \"%s\"",
+						full_fname(buf), sl);
+				}
 			}
 			do_unlink(fname);
 			kept = 1;

generator.c

@@ -1868,15 +1868,21 @@ static void recv_generator(char *fname, struct file_struct *file, int ndx,
 			close(fd);
 			goto cleanup;
 		}
-		if ((f_copy = do_open(backupptr, O_WRONLY | O_CREAT | O_TRUNC | O_EXCL, 0600)) < 0
-		 && (errno != ENOENT || make_bak_dir(backupptr) < 0
-		  || (f_copy = do_open(backupptr, O_WRONLY | O_CREAT | O_TRUNC | O_EXCL, 0600)) < 0)) {
-			rsyserr(FERROR_XFER, errno, "open %s",
-				full_fname(backupptr));
-			unmake_file(back_file);
-			back_file = NULL;
-			close(fd);
-			goto cleanup;
+		if ((f_copy = do_open(backupptr, O_WRONLY | O_CREAT | O_TRUNC | O_EXCL, 0600)) < 0) {
+			int save_errno = errno ? errno : EINVAL; /* 0 paranoia */
+			if (errno == ENOENT && make_bak_dir(backupptr) == 0) {
+				if ((f_copy = do_open(backupptr, O_WRONLY | O_CREAT | O_TRUNC | O_EXCL, 0600)) < 0)
+					save_errno = errno ? errno : save_errno;
+				else
+					save_errno = 0;
+			}
+			if (save_errno) {
+				rsyserr(FERROR_XFER, save_errno, "open %s", full_fname(backupptr));
+				unmake_file(back_file);
+				back_file = NULL;
+				close(fd);
+				goto cleanup;
+			}
 		}
 		fnamecmp_type = FNAMECMP_BACKUP;
 	}

util.c

@@ -275,38 +275,54 @@ int copy_file(const char *source, const char *dest, int ofd,
 	int len;   /* Number of bytes read into `buf'. */
 
 	if ((ifd = do_open(source, O_RDONLY, 0)) < 0) {
+		int save_errno = errno;
 		rsyserr(FERROR_XFER, errno, "open %s", full_fname(source));
+		errno = save_errno;
 		return -1;
 	}
 
 	if (ofd < 0) {
 		if (robust_unlink(dest) && errno != ENOENT) {
+			int save_errno = errno;
 			rsyserr(FERROR_XFER, errno, "unlink %s", full_fname(dest));
+			errno = save_errno;
 			return -1;
 		}
 
-		if ((ofd = do_open(dest, O_WRONLY | O_CREAT | O_TRUNC | O_EXCL, mode)) < 0
-		 && (!create_bak_dir || errno != ENOENT || make_bak_dir(dest) < 0
-		  || (ofd = do_open(dest, O_WRONLY | O_CREAT | O_TRUNC | O_EXCL, mode)) < 0)) {
-			rsyserr(FERROR_XFER, errno, "open %s", full_fname(dest));
-			close(ifd);
-			return -1;
+		if ((ofd = do_open(dest, O_WRONLY | O_CREAT | O_TRUNC | O_EXCL, mode)) < 0) {
+			int save_errno = errno ? errno : EINVAL; /* 0 paranoia */
+			if (create_bak_dir && errno == ENOENT && make_bak_dir(dest) == 0) {
+				if ((ofd = do_open(dest, O_WRONLY | O_CREAT | O_TRUNC | O_EXCL, mode)) < 0)
+					save_errno = errno ? errno : save_errno;
+				else
+					save_errno = 0;
+			}
+			if (save_errno) {
+				rsyserr(FERROR_XFER, save_errno, "open %s", full_fname(dest));
+				close(ifd);
+				errno = save_errno;
+				return -1;
+			}
 		}
 	}
 
 	while ((len = safe_read(ifd, buf, sizeof buf)) > 0) {
 		if (full_write(ofd, buf, len) < 0) {
+			int save_errno = errno;
 			rsyserr(FERROR_XFER, errno, "write %s", full_fname(dest));
 			close(ifd);
 			close(ofd);
+			errno = save_errno;
 			return -1;
 		}
 	}
 
 	if (len < 0) {
+		int save_errno = errno;
 		rsyserr(FERROR_XFER, errno, "read %s", full_fname(source));
 		close(ifd);
 		close(ofd);
+		errno = save_errno;
 		return -1;
 	}
 
@@ -316,8 +332,10 @@ int copy_file(const char *source, const char *dest, int ofd,
 	}
 
 	if (close(ofd) < 0) {
+		int save_errno = errno;
 		rsyserr(FERROR_XFER, errno, "close failed on %s",
 			full_fname(dest));
+		errno = save_errno;
 		return -1;
 	}
 
@@ -401,8 +419,11 @@ int robust_rename(const char *from, const char *to, const char *partialptr,
 		switch (errno) {
 #ifdef ETXTBSY
 		case ETXTBSY:
-			if (robust_unlink(to) != 0)
+			if (robust_unlink(to) != 0) {
+				errno = ETXTBSY;
 				return -1;
+			}
+			errno = ETXTBSY;
 			break;
 #endif
 		case EXDEV: