X-Git-Url: https://git.librecmc.org/?a=blobdiff_plain;f=libbb%2Fcopy_file.c;h=0135831fe0a35536ddfc090f74e18f36dd0c9cf1;hb=d3d004dd3507f841745956a035fff68936378f9c;hp=64b65b9faf69a92343bdeb762c151790552d875b;hpb=aad1a88c76f208d188fd061e3723bd637437e8d5;p=oweals%2Fbusybox.git

diff --git a/libbb/copy_file.c b/libbb/copy_file.c
index 64b65b9fa..0135831fe 100644
--- a/libbb/copy_file.c
+++ b/libbb/copy_file.c
@@ -1,180 +1,282 @@
 /* vi: set sw=4 ts=4: */
 /*
- * Utility routines.
+ * Mini copy_file implementation for busybox
  *
- * Copyright (C) tons of folks.  Tracking down who wrote what
- * isn't something I'm going to worry about...  If you wrote something
- * here, please feel free to acknowledge your work.
+ * Copyright (C) 2001 by Matt Kraai <kraai@alumni.carnegiemellon.edu>
  *
- * 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 2 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, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
- *
- * Based in part on code from sash, Copyright (c) 1999 by David I. Bell 
- * Permission has been granted to redistribute this code under the GPL.
+ * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
  *
  */
 
-#include <stdio.h>
-#include <errno.h>
-#include <utime.h>
-#include <unistd.h>
-#include <fcntl.h>
-#include <sys/stat.h>
 #include "libbb.h"
 
-
-/*
- * Copy one file to another, while possibly preserving its modes, times, and
- * modes.  Returns TRUE if successful, or FALSE on a failure with an error
- * message output.  (Failure is not indicated if attributes cannot be set.)
- * -Erik Andersen
- */
-int
-copy_file(const char *srcName, const char *destName,
-		 int setModes, int followLinks, int forceFlag)
+static int retry_overwrite(const char *dest, int flags)
 {
-	int rfd;
-	int wfd;
-	int status;
-	struct stat srcStatBuf;
-	struct stat dstStatBuf;
-	struct utimbuf times;
-
-	if (followLinks == TRUE)
-		status = stat(srcName, &srcStatBuf);
-	else
-		status = lstat(srcName, &srcStatBuf);
-
-	if (status < 0) {
-		perror_msg("%s", srcName);
-		return FALSE;
+	if (!(flags & (FILEUTILS_FORCE|FILEUTILS_INTERACTIVE))) {
+		fprintf(stderr, "'%s' exists\n", dest);
+		return -1;
+	}
+	if (flags & FILEUTILS_INTERACTIVE) {
+		fprintf(stderr, "%s: overwrite '%s'? ", applet_name, dest);
+		if (!bb_ask_confirmation())
+			return 0; // not allowed to overwrite
 	}
+	if (unlink(dest) < 0) {
+		bb_perror_msg("cannot remove '%s'", dest);
+		return -1; // error
+	}
+	return 1; // ok (to try again)
+}
 
-	if (followLinks == TRUE)
-		status = stat(destName, &dstStatBuf);
-	else
-		status = lstat(destName, &dstStatBuf);
+int copy_file(const char *source, const char *dest, int flags)
+{
+	struct stat source_stat;
+	struct stat dest_stat;
+	int status = 0;
+	signed char dest_exists = 0;
+	signed char ovr;
 
-	if (status < 0 || forceFlag==TRUE) {
-		unlink(destName);
-		dstStatBuf.st_ino = -1;
-		dstStatBuf.st_dev = -1;
-	}
+#define FLAGS_DEREF (flags & FILEUTILS_DEREFERENCE)
 
-	if ((srcStatBuf.st_dev == dstStatBuf.st_dev) &&
-		(srcStatBuf.st_ino == dstStatBuf.st_ino)) {
-		error_msg("Copying file \"%s\" to itself", srcName);
-		return FALSE;
+	if ((FLAGS_DEREF ? stat : lstat)(source, &source_stat) < 0) {
+		// This may be a dangling symlink.
+		// Making [sym]links to dangling symlinks works, so...
+		if (flags & (FILEUTILS_MAKE_SOFTLINK|FILEUTILS_MAKE_HARDLINK))
+			goto make_links;
+		bb_perror_msg("cannot stat '%s'", source);
+		return -1;
 	}
 
-	if (S_ISDIR(srcStatBuf.st_mode)) {
-		//fprintf(stderr, "copying directory %s to %s\n", srcName, destName);
-		/* Make sure the directory is writable */
-		status = mkdir(destName, 0777777 ^ umask(0));
-		if (status < 0 && errno != EEXIST) {
-			perror_msg("%s", destName);
-			return FALSE;
-		}
-	} else if (S_ISLNK(srcStatBuf.st_mode)) {
-		char link_val[BUFSIZ + 1];
-		int link_size;
-
-		//fprintf(stderr, "copying link %s to %s\n", srcName, destName);
-		/* Warning: This could possibly truncate silently, to BUFSIZ chars */
-		link_size = readlink(srcName, &link_val[0], BUFSIZ);
-		if (link_size < 0) {
-			perror_msg("%s", srcName);
-			return FALSE;
-		}
-		link_val[link_size] = '\0';
-		status = symlink(link_val, destName);
-		if (status < 0) {
-			perror_msg("%s", destName);
-			return FALSE;
-		}
-#if (__GLIBC__ >= 2) && (__GLIBC_MINOR__ >= 1)
-		if (setModes == TRUE) {
-			/* Try to set owner, but fail silently like GNU cp */
-			lchown(destName, srcStatBuf.st_uid, srcStatBuf.st_gid);
-		}
-#endif
-		return TRUE;
-	} else if (S_ISFIFO(srcStatBuf.st_mode)) {
-		//fprintf(stderr, "copying fifo %s to %s\n", srcName, destName);
-		if (mkfifo(destName, 0644) < 0) {
-			perror_msg("%s", destName);
-			return FALSE;
-		}
-	} else if (S_ISBLK(srcStatBuf.st_mode) || S_ISCHR(srcStatBuf.st_mode)
-			   || S_ISSOCK(srcStatBuf.st_mode)) {
-		//fprintf(stderr, "copying soc, blk, or chr %s to %s\n", srcName, destName);
-		if (mknod(destName, srcStatBuf.st_mode, srcStatBuf.st_rdev) < 0) {
-			perror_msg("%s", destName);
-			return FALSE;
-		}
-	} else if (S_ISREG(srcStatBuf.st_mode)) {
-		//fprintf(stderr, "copying regular file %s to %s\n", srcName, destName);
-		rfd = open(srcName, O_RDONLY);
-		if (rfd < 0) {
-			perror_msg("%s", srcName);
-			return FALSE;
-		}
-
-	 	wfd = open(destName, O_WRONLY | O_CREAT | O_TRUNC,
-				 srcStatBuf.st_mode);
-		if (wfd < 0) {
-			perror_msg("%s", destName);
-			close(rfd);
-			return FALSE;
-		}
-
-		if (copy_file_chunk(rfd, wfd, srcStatBuf.st_size)==FALSE)
-			goto error_exit;	
-		
-		close(rfd);
-		if (close(wfd) < 0) {
-			return FALSE;
+	if (lstat(dest, &dest_stat) < 0) {
+		if (errno != ENOENT) {
+			bb_perror_msg("cannot stat '%s'", dest);
+			return -1;
+		}
+	} else {
+		if (source_stat.st_dev == dest_stat.st_dev
+		 && source_stat.st_ino == dest_stat.st_ino
+		) {
+			bb_error_msg("'%s' and '%s' are the same file", source, dest);
+			return -1;
 		}
+		dest_exists = 1;
 	}
 
-	if (setModes == TRUE) {
-		/* This is fine, since symlinks never get here */
-		if (chown(destName, srcStatBuf.st_uid, srcStatBuf.st_gid) < 0)
-			perror_msg_and_die("%s", destName);
-		if (chmod(destName, srcStatBuf.st_mode) < 0)
-			perror_msg_and_die("%s", destName);
-		times.actime = srcStatBuf.st_atime;
-		times.modtime = srcStatBuf.st_mtime;
-		if (utime(destName, &times) < 0)
-			perror_msg_and_die("%s", destName);
+	if (S_ISDIR(source_stat.st_mode)) {
+		DIR *dp;
+		struct dirent *d;
+		mode_t saved_umask = 0;
+
+		if (!(flags & FILEUTILS_RECUR)) {
+			bb_error_msg("omitting directory '%s'", source);
+			return -1;
+		}
+
+		/* Create DEST.  */
+		if (dest_exists) {
+			if (!S_ISDIR(dest_stat.st_mode)) {
+				bb_error_msg("target '%s' is not a directory", dest);
+				return -1;
+			}
+		} else {
+			mode_t mode;
+			saved_umask = umask(0);
+
+			mode = source_stat.st_mode;
+			if (!(flags & FILEUTILS_PRESERVE_STATUS))
+				mode = source_stat.st_mode & ~saved_umask;
+			mode |= S_IRWXU;
+
+			if (mkdir(dest, mode) < 0) {
+				umask(saved_umask);
+				bb_perror_msg("cannot create directory '%s'", dest);
+				return -1;
+			}
+
+			umask(saved_umask);
+		}
+
+		/* Recursively copy files in SOURCE.  */
+		dp = opendir(source);
+		if (dp == NULL) {
+			status = -1;
+			goto preserve_status;
+		}
+
+		while ((d = readdir(dp)) != NULL) {
+			char *new_source, *new_dest;
+
+			new_source = concat_subpath_file(source, d->d_name);
+			if (new_source == NULL)
+				continue;
+			new_dest = concat_path_file(dest, d->d_name);
+			if (copy_file(new_source, new_dest, flags) < 0)
+				status = -1;
+			free(new_source);
+			free(new_dest);
+		}
+		closedir(dp);
+
+		if (!dest_exists
+		 && chmod(dest, source_stat.st_mode & ~saved_umask) < 0
+		) {
+			bb_perror_msg("cannot change permissions of '%s'", dest);
+			status = -1;
+		}
+
+	} else if (flags & (FILEUTILS_MAKE_SOFTLINK|FILEUTILS_MAKE_HARDLINK)) {
+		int (*lf)(const char *oldpath, const char *newpath);
+ make_links:
+		// Hmm... maybe
+		// if (DEREF && MAKE_SOFTLINK) source = realpath(source) ?
+		// (but realpath returns NULL on dangling symlinks...)
+		lf = (flags & FILEUTILS_MAKE_SOFTLINK) ? symlink : link;
+		if (lf(source, dest) < 0) {
+			ovr = retry_overwrite(dest, flags);
+			if (ovr <= 0)
+				return ovr;
+			if (lf(source, dest) < 0) {
+				bb_perror_msg("cannot create link '%s'", dest);
+				return -1;
+			}
+		}
+		return 0;
+
+	} else if (S_ISREG(source_stat.st_mode)
+	// Huh? DEREF uses stat, which never returns links IIRC...
+	 || (FLAGS_DEREF && S_ISLNK(source_stat.st_mode)) 
+	) {
+		int src_fd;
+		int dst_fd;
+		if (ENABLE_FEATURE_PRESERVE_HARDLINKS) {
+			char *link_name;
+
+			if (!FLAGS_DEREF
+			 && is_in_ino_dev_hashtable(&source_stat, &link_name)
+			) {
+				if (link(link_name, dest) < 0) {
+					ovr = retry_overwrite(dest, flags);
+					if (ovr <= 0)
+						return ovr;
+					if (link(link_name, dest) < 0) {
+						bb_perror_msg("cannot create link '%s'", dest);
+						return -1;
+					}
+				}
+				return 0;
+			}
+			// TODO: probably is_in_.. and add_to_...
+			// can be combined: find_or_add_...
+			add_to_ino_dev_hashtable(&source_stat, dest);
+		}
+
+		src_fd = open(source, O_RDONLY);
+		if (src_fd == -1) {
+			bb_perror_msg("cannot open '%s'", source);
+			return -1;
+		}
+
+		// POSIX: if exists and -i, ask (w/o -i assume yes).
+		// Then open w/o EXCL.
+		// If open still fails and -f, try unlink, then try open again.
+		// Result: a mess:
+		// If dest is a softlink, we overwrite softlink's destination!
+		// (or fail, if it points to dir/nonexistent location/etc).
+		// This is strange, but POSIX-correct.
+		// coreutils cp has --remove-destination to override this...
+		dst_fd = open(dest, (flags & FILEUTILS_INTERACTIVE)
+				? O_WRONLY|O_CREAT|O_TRUNC|O_EXCL
+				: O_WRONLY|O_CREAT|O_TRUNC, source_stat.st_mode);
+		if (dst_fd == -1) {
+			// We would not do POSIX insanity. -i asks,
+			// then _unlinks_ the offender. Presto.
+			// Or else we will end up having 3 open()s!
+			ovr = retry_overwrite(dest, flags);
+			if (ovr <= 0) {
+				close(src_fd);
+				return ovr;
+			}
+			dst_fd = open(dest, O_WRONLY|O_CREAT|O_TRUNC, source_stat.st_mode);
+			if (dst_fd == -1) {
+				bb_perror_msg("cannot open '%s'", dest);
+				close(src_fd);
+				return -1;
+			}
+		}
+
+		if (bb_copyfd_eof(src_fd, dst_fd) == -1)
+			status = -1;
+		if (close(dst_fd) < 0) {
+			bb_perror_msg("cannot close '%s'", dest);
+			status = -1;
+		}
+		if (close(src_fd) < 0) {
+			bb_perror_msg("cannot close '%s'", source);
+			status = -1;
+		}
+
+	} else if (S_ISBLK(source_stat.st_mode) || S_ISCHR(source_stat.st_mode)
+	 || S_ISSOCK(source_stat.st_mode) || S_ISFIFO(source_stat.st_mode)
+	 || S_ISLNK(source_stat.st_mode)
+	) {
+		// We are lazy here, a bit lax with races...
+		if (dest_exists) {
+			ovr = retry_overwrite(dest, flags);
+			if (ovr <= 0)
+				return ovr;
+		}
+		if (S_ISFIFO(source_stat.st_mode)) {
+			if (mkfifo(dest, source_stat.st_mode) < 0) {
+				bb_perror_msg("cannot create fifo '%s'", dest);
+				return -1;
+			}
+		} else if (S_ISLNK(source_stat.st_mode)) {
+			char *lpath;
+
+			lpath = xreadlink(source);
+			if (symlink(lpath, dest) < 0) {
+				bb_perror_msg("cannot create symlink '%s'", dest);
+				free(lpath);
+				return -1;
+			}
+			free(lpath);
+
+			if (flags & FILEUTILS_PRESERVE_STATUS)
+				if (lchown(dest, source_stat.st_uid, source_stat.st_gid) < 0)
+					bb_perror_msg("cannot preserve %s of '%s'", "ownership", dest);
+
+			return 0;
+
+		} else {
+			if (mknod(dest, source_stat.st_mode, source_stat.st_rdev) < 0) {
+				bb_perror_msg("cannot create '%s'", dest);
+				return -1;
+			}
+		}
+	} else {
+		bb_error_msg("internal error: unrecognized file type");
+		return -1;
 	}
 
-	return TRUE;
+ preserve_status:
 
-  error_exit:
-	perror_msg("%s", destName);
-	close(rfd);
-	close(wfd);
+	if (flags & FILEUTILS_PRESERVE_STATUS
+	/* Cannot happen: */
+	/* && !(flags & (FILEUTILS_MAKE_SOFTLINK|FILEUTILS_MAKE_HARDLINK)) */
+	) {
+		struct utimbuf times;
 
-	return FALSE;
-}
+		times.actime = source_stat.st_atime;
+		times.modtime = source_stat.st_mtime;
+		if (utime(dest, &times) < 0)
+			bb_perror_msg("cannot preserve %s of '%s'", "times", dest);
+		if (chown(dest, source_stat.st_uid, source_stat.st_gid) < 0) {
+			source_stat.st_mode &= ~(S_ISUID | S_ISGID);
+			bb_perror_msg("cannot preserve %s of '%s'", "ownership", dest);
+		}
+		if (chmod(dest, source_stat.st_mode) < 0)
+			bb_perror_msg("cannot preserve %s of '%s'", "permissions", dest);
+	}
 
-/* END CODE */
-/*
-Local Variables:
-c-file-style: "linux"
-c-basic-offset: 4
-tab-width: 4
-End:
-*/
+	return status;
+}