generator.c

Rsync 3.0.5 source code

/*
 * Routines that are exclusive to the generator process.
 *
 * Copyright (C) 1996-2000 Andrew Tridgell
 * Copyright (C) 1996 Paul Mackerras
 * Copyright (C) 2002 Martin Pool <[e-mail]>
 * Copyright (C) 2003-2008 Wayne Davison
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, visit the http://fsf.org website.
 */

#include "rsync.h"

extern int verbose;
extern int dry_run;
extern int do_xfers;
extern int stdout_format_has_i;
extern int logfile_format_has_i;
extern int am_root;
extern int am_server;
extern int am_daemon;
extern int inc_recurse;
extern int do_progress;
extern int relative_paths;
extern int implied_dirs;
extern int keep_dirlinks;
extern int preserve_acls;
extern int preserve_xattrs;
extern int preserve_links;
extern int preserve_devices;
extern int preserve_specials;
extern int preserve_hard_links;
extern int preserve_executability;
extern int preserve_perms;
extern int preserve_times;
extern int uid_ndx;
extern int gid_ndx;
extern int delete_mode;
extern int delete_before;
extern int delete_during;
extern int delete_after;
extern int msgdone_cnt;
extern int ignore_errors;
extern int remove_source_files;
extern int delay_updates;
extern int update_only;
extern int ignore_existing;
extern int ignore_non_existing;
extern int inplace;
extern int append_mode;
extern int make_backups;
extern int csum_length;
extern int ignore_times;
extern int size_only;
extern OFF_T max_size;
extern OFF_T min_size;
extern int io_error;
extern int flist_eof;
extern int allowed_lull;
extern int sock_f_out;
extern int ignore_timeout;
extern int protocol_version;
extern int file_total;
extern int fuzzy_basis;
extern int always_checksum;
extern int checksum_len;
extern char *partial_dir;
extern char *basis_dir[];
extern int compare_dest;
extern int copy_dest;
extern int link_dest;
extern int whole_file;
extern int list_only;
extern int read_batch;
extern int safe_symlinks;
extern long block_size; /* "long" because popt can't set an int32. */
extern int unsort_ndx;
extern int max_delete;
extern int force_delete;
extern int one_file_system;
extern struct stats stats;
extern dev_t filesystem_dev;
extern mode_t orig_umask;
extern uid_t our_uid;
extern char *backup_dir;
extern char *backup_suffix;
extern int backup_suffix_len;
extern struct file_list *cur_flist, *first_flist, *dir_flist;
extern struct filter_list_struct daemon_filter_list;

int ignore_perishable = 0;
int non_perishable_cnt = 0;
int maybe_ATTRS_REPORT = 0;

static dev_t dev_zero;
static int deletion_count = 0; /* used to implement --max-delete */
static int deldelay_size = 0, deldelay_cnt = 0;
static char *deldelay_buf = NULL;
static int deldelay_fd = -1;
static int loopchk_limit;
static int dir_tweaking;
static int symlink_timeset_failed_flags;
static int need_retouch_dir_times;
static int need_retouch_dir_perms;
static const char *solo_file = NULL;

/* For calling delete_item() and delete_dir_contents(). */
#define DEL_NO_UID_WRITE 	(1<<0) /* file/dir has our uid w/o write perm */
#define DEL_RECURSE		(1<<1) /* if dir, delete all contents */
#define DEL_DIR_IS_EMPTY	(1<<2) /* internal delete_FUNCTIONS use only */
#define DEL_FOR_FILE		(1<<3) /* making room for a replacement file */
#define DEL_FOR_DIR		(1<<4) /* making room for a replacement dir */
#define DEL_FOR_SYMLINK 	(1<<5) /* making room for a replacement symlink */
#define DEL_FOR_DEVICE		(1<<6) /* making room for a replacement device */
#define DEL_FOR_SPECIAL 	(1<<7) /* making room for a replacement special */

#define DEL_MAKE_ROOM (DEL_FOR_FILE|DEL_FOR_DIR|DEL_FOR_SYMLINK|DEL_FOR_DEVICE|DEL_FOR_SPECIAL)

enum nonregtype {
    TYPE_DIR, TYPE_SPECIAL, TYPE_DEVICE, TYPE_SYMLINK
};

enum delret {
    DR_SUCCESS = 0, DR_FAILURE, DR_AT_LIMIT, DR_NOT_EMPTY
};

/* Forward declarations. */
static enum delret delete_dir_contents(char *fname, uint16 flags);
#ifdef SUPPORT_HARD_LINKS
static void handle_skipped_hlink(struct file_struct *file, int itemizing,
				 enum logcode code, int f_out);
#endif

static int is_backup_file(char *fn)
{
	int k = strlen(fn) - backup_suffix_len;
	return k > 0 && strcmp(fn+k, backup_suffix) == 0;
}

/* Delete a file or directory.  If DEL_RECURSE is set in the flags, this will
 * delete recursively.
 *
 * Note that fbuf must point to a MAXPATHLEN buffer if the mode indicates it's
 * a directory! (The buffer is used for recursion, but returned unchanged.)
 */
static enum delret delete_item(char *fbuf, uint16 mode, uint16 flags)
{
	enum delret ret;
	char *what;
	int ok;

	if (verbose > 2) {
		rprintf(FINFO, "delete_item(%s) mode=%o flags=%d\n",
			fbuf, (int)mode, (int)flags);
	}

	if (flags & DEL_NO_UID_WRITE)
		do_chmod(fbuf, mode | S_IWUSR);

	if (S_ISDIR(mode) && !(flags & DEL_DIR_IS_EMPTY)) {
		int save_uid_ndx = uid_ndx;
		/* This only happens on the first call to delete_item() since
		 * delete_dir_contents() always calls us w/DEL_DIR_IS_EMPTY. */
		if (!uid_ndx)
			uid_ndx = ++file_extra_cnt;
		ignore_perishable = 1;
		/* If DEL_RECURSE is not set, this just reports emptiness. */
		ret = delete_dir_contents(fbuf, flags);
		ignore_perishable = 0;
		if (!save_uid_ndx) {
			--file_extra_cnt;
			uid_ndx = 0;
		}
		if (ret == DR_NOT_EMPTY || ret == DR_AT_LIMIT)
			goto check_ret;
		/* OK: try to delete the directory. */
	}

	if (!(flags & DEL_MAKE_ROOM) && max_delete >= 0 && ++deletion_count > max_delete)
		return DR_AT_LIMIT;

	if (S_ISDIR(mode)) {
		what = "rmdir";
		ok = do_rmdir(fbuf) == 0;
	} else if (make_backups > 0 && (backup_dir || !is_backup_file(fbuf))) {
		what = "make_backup";
		ok = make_backup(fbuf);
	} else {
		what = "unlink";
		ok = robust_unlink(fbuf) == 0;
	}

	if (ok) {
		if (!(flags & DEL_MAKE_ROOM))
			log_delete(fbuf, mode);
		ret = DR_SUCCESS;
	} else {
		if (S_ISDIR(mode) && errno == ENOTEMPTY) {
			rprintf(FINFO, "cannot delete non-empty directory: %s\n",
				fbuf);
			ret = DR_NOT_EMPTY;
		} else if (errno != ENOENT) {
			rsyserr(FERROR, errno, "delete_file: %s(%s) failed",
				what, fbuf);
			ret = DR_FAILURE;
		} else {
			deletion_count--;
			ret = DR_SUCCESS;
		}
	}

  check_ret:
	if (ret != DR_SUCCESS && flags & DEL_MAKE_ROOM) {
		const char *desc;
		switch (flags & DEL_MAKE_ROOM) {
		case DEL_FOR_FILE: desc = "regular file"; break;
		case DEL_FOR_DIR: desc = "directory"; break;
		case DEL_FOR_SYMLINK: desc = "symlink"; break;
		case DEL_FOR_DEVICE: desc = "device file"; break;
		case DEL_FOR_SPECIAL: desc = "special file"; break;
		default: exit_cleanup(RERR_UNSUPPORTED); /* IMPOSSIBLE */
		}
		rprintf(FERROR_XFER, "could not make way for new %s: %s\n",
			desc, fbuf);
	}
	return ret;
}

/* The directory is about to be deleted: if DEL_RECURSE is given, delete all
 * its contents, otherwise just checks for content.  Returns DR_SUCCESS or
 * DR_NOT_EMPTY.  Note that fname must point to a MAXPATHLEN buffer!  (The
 * buffer is used for recursion, but returned unchanged.)
 */
static enum delret delete_dir_contents(char *fname, uint16 flags)
{
	struct file_list *dirlist;
	enum delret ret;
	unsigned remainder;
	void *save_filters;
	int j, dlen;
	char *p;

	if (verbose > 3) {
		rprintf(FINFO, "delete_dir_contents(%s) flags=%d\n",
			fname, flags);
	}

	dlen = strlen(fname);
	save_filters = push_local_filters(fname, dlen);

	non_perishable_cnt = 0;
	dirlist = get_dirlist(fname, dlen, 0);
	ret = non_perishable_cnt ? DR_NOT_EMPTY : DR_SUCCESS;

	if (!dirlist->used)
		goto done;

	if (!(flags & DEL_RECURSE)) {
		ret = DR_NOT_EMPTY;
		goto done;
	}

	p = fname + dlen;
	if (dlen != 1 || *fname != '/')
		*p++ = '/';
	remainder = MAXPATHLEN - (p - fname);

	/* We do our own recursion, so make delete_item() non-recursive. */
	flags = (flags & ~(DEL_RECURSE|DEL_MAKE_ROOM|DEL_NO_UID_WRITE))
	      | DEL_DIR_IS_EMPTY;

	for (j = dirlist->used; j--; ) {
		struct file_struct *fp = dirlist->files[j];

		if (fp->flags & FLAG_MOUNT_DIR && S_ISDIR(fp->mode)) {
			if (verbose > 1) {
				rprintf(FINFO,
				    "mount point, %s, pins parent directory\n",
				    f_name(fp, NULL));
			}
			ret = DR_NOT_EMPTY;
			continue;
		}

		strlcpy(p, fp->basename, remainder);
		if (!(fp->mode & S_IWUSR) && !am_root && (uid_t)F_OWNER(fp) == our_uid)
			do_chmod(fname, fp->mode | S_IWUSR);
		/* Save stack by recursing to ourself directly. */
		if (S_ISDIR(fp->mode)) {
			if (delete_dir_contents(fname, flags | DEL_RECURSE) != DR_SUCCESS)
				ret = DR_NOT_EMPTY;
		}
		if (delete_item(fname, fp->mode, flags) != DR_SUCCESS)
			ret = DR_NOT_EMPTY;
	}

	fname[dlen] = '\0';

  done:
	flist_free(dirlist);
	pop_local_filters(save_filters);

	if (ret == DR_NOT_EMPTY) {
		rprintf(FINFO, "cannot delete non-empty directory: %s\n",
			fname);
	}
	return ret;
}

static int start_delete_delay_temp(void)
{
	char fnametmp[MAXPATHLEN];
	int save_dry_run = dry_run;

	dry_run = 0;
	if (!get_tmpname(fnametmp, "deldelay")
	 || (deldelay_fd = do_mkstemp(fnametmp, 0600)) < 0) {
		rprintf(FINFO, "NOTE: Unable to create delete-delay temp file%s.\n",
			inc_recurse ? "" : " -- switching to --delete-after");
		delete_during = 0;
		delete_after = !inc_recurse;
		dry_run = save_dry_run;
		return 0;
	}
	unlink(fnametmp);
	dry_run = save_dry_run;
	return 1;
}

static int flush_delete_delay(void)
{
	if (deldelay_fd < 0 && !start_delete_delay_temp())
		return 0;
	if (write(deldelay_fd, deldelay_buf, deldelay_cnt) != deldelay_cnt) {
		rsyserr(FERROR, errno, "flush of delete-delay buffer");
		delete_during = 0;
		delete_after = !inc_recurse;
		close(deldelay_fd);
		return 0;
	}
	deldelay_cnt = 0;
	return 1;
}

static int remember_delete(struct file_struct *file, const char *fname, int flags)
{
	int len;

	if (deldelay_cnt == deldelay_size && !flush_delete_delay())
		return 0;

	if (flags & DEL_NO_UID_WRITE)
		deldelay_buf[deldelay_cnt++] = '!';

	while (1) {
		len = snprintf(deldelay_buf + deldelay_cnt,
			       deldelay_size - deldelay_cnt,
			       "%x %s%c",
			       (int)file->mode, fname, '\0');
		if ((deldelay_cnt += len) <= deldelay_size)
			break;
		deldelay_cnt -= len;
		if (!flush_delete_delay())
			return 0;
	}

	return 1;
}

static int read_delay_line(char *buf, int *flags_p)
{
	static int read_pos = 0;
	int j, len, mode;
	char *bp, *past_space;

	while (1) {
		for (j = read_pos; j < deldelay_cnt && deldelay_buf[j]; j++) {}
		if (j < deldelay_cnt)
			break;
		if (deldelay_fd < 0) {
			if (j > read_pos)
				goto invalid_data;
			return -1;
		}
		deldelay_cnt -= read_pos;
		if (deldelay_cnt == deldelay_size)
			goto invalid_data;
		if (deldelay_cnt && read_pos) {
			memmove(deldelay_buf, deldelay_buf + read_pos,
				deldelay_cnt);
		}
		len = read(deldelay_fd, deldelay_buf + deldelay_cnt,
			   deldelay_size - deldelay_cnt);
		if (len == 0) {
			if (deldelay_cnt) {
				rprintf(FERROR,
				    "ERROR: unexpected EOF in delete-delay file.\n");
			}
			return -1;
		}
		if (len < 0) {
			rsyserr(FERROR, errno,
				"reading delete-delay file");
			return -1;
		}
		deldelay_cnt += len;
		read_pos = 0;
	}

	bp = deldelay_buf + read_pos;
	if (*bp == '!') {
		bp++;
		*flags_p = DEL_NO_UID_WRITE;
	} else
		*flags_p = 0;

	if (sscanf(bp, "%x ", &mode) != 1) {
	  invalid_data:
		rprintf(FERROR, "ERROR: invalid data in delete-delay file.\n");
		return -1;
	}
	past_space = strchr(bp, ' ') + 1;
	len = j - read_pos - (past_space - bp) + 1; /* count the '\0' */
	read_pos = j + 1;

	if (len > MAXPATHLEN) {
		rprintf(FERROR, "ERROR: filename too long in delete-delay file.\n");
		return -1;
	}

	/* The caller needs the name in a MAXPATHLEN buffer, so we copy it
	 * instead of returning a pointer to our buffer. */
	memcpy(buf, past_space, len);

	return mode;
}

static void do_delayed_deletions(char *delbuf)
{
	int mode, flags;

	if (deldelay_fd >= 0) {
		if (deldelay_cnt && !flush_delete_delay())
			return;
		lseek(deldelay_fd, 0, 0);
	}
	while ((mode = read_delay_line(delbuf, &flags)) >= 0)
		delete_item(delbuf, mode, flags | DEL_RECURSE);
	if (deldelay_fd >= 0)
		close(deldelay_fd);
}

/* This function is used to implement per-directory deletion, and is used by
 * all the --delete-WHEN options.  Note that the fbuf pointer must point to a
 * MAXPATHLEN buffer with the name of the directory in it (the functions we
 * call will append names onto the end, but the old dir value will be restored
 * on exit). */
static void delete_in_dir(char *fbuf, struct file_struct *file, dev_t *fs_dev)
{
	static int already_warned = 0;