X-Git-Url: https://git.librecmc.org/?a=blobdiff_plain;f=libbb%2Fcopy_file.c;h=0135831fe0a35536ddfc090f74e18f36dd0c9cf1;hb=ab24e18c7a32ee1637be19f239e9dd9d7c7f6534;hp=5f667cf4f79d9683c33c2509faf3d99152b9e05a;hpb=a9a220b92a9a88babb0080f0dfa6d27bac5edd6f;p=oweals%2Fbusybox.git

diff --git a/libbb/copy_file.c b/libbb/copy_file.c
index 5f667cf4f..0135831fe 100644
--- a/libbb/copy_file.c
+++ b/libbb/copy_file.c
@@ -4,60 +4,61 @@
  *
  * 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
+ * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
  *
  */
 
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <unistd.h>
-#include <fcntl.h>
-#include <utime.h>
-#include <errno.h>
-#include <dirent.h>
-#include <stdlib.h>
-#include <string.h>
+#include "libbb.h"
 
-#include "busybox.h"
+static int retry_overwrite(const char *dest, int flags)
+{
+	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)
+}
 
 int copy_file(const char *source, const char *dest, int flags)
 {
 	struct stat source_stat;
 	struct stat dest_stat;
-	int dest_exists = 0;
 	int status = 0;
+	signed char dest_exists = 0;
+	signed char ovr;
+
+#define FLAGS_DEREF (flags & FILEUTILS_DEREFERENCE)
 
-	if ((!(flags & FILEUTILS_DEREFERENCE) &&
-			lstat(source, &source_stat) < 0) ||
-			((flags & FILEUTILS_DEREFERENCE) &&
-			 stat(source, &source_stat) < 0)) {
-		perror_msg("%s", source);
+	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 (lstat(dest, &dest_stat) < 0) {
 		if (errno != ENOENT) {
-			perror_msg("unable to stat `%s'", dest);
+			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) {
-		error_msg("`%s' and `%s' are the same file", source, dest);
-		return -1;
-	}
+		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;
 	}
 
@@ -67,14 +68,14 @@ int copy_file(const char *source, const char *dest, int flags)
 		mode_t saved_umask = 0;
 
 		if (!(flags & FILEUTILS_RECUR)) {
-			error_msg("%s: omitting directory", source);
+			bb_error_msg("omitting directory '%s'", source);
 			return -1;
 		}
 
 		/* Create DEST.  */
 		if (dest_exists) {
 			if (!S_ISDIR(dest_stat.st_mode)) {
-				error_msg("`%s' is not a directory", dest);
+				bb_error_msg("target '%s' is not a directory", dest);
 				return -1;
 			}
 		} else {
@@ -88,7 +89,7 @@ int copy_file(const char *source, const char *dest, int flags)
 
 			if (mkdir(dest, mode) < 0) {
 				umask(saved_umask);
-				perror_msg("cannot create directory `%s'", dest);
+				bb_perror_msg("cannot create directory '%s'", dest);
 				return -1;
 			}
 
@@ -96,173 +97,185 @@ int copy_file(const char *source, const char *dest, int flags)
 		}
 
 		/* Recursively copy files in SOURCE.  */
-		if ((dp = opendir(source)) == NULL) {
-			perror_msg("unable to open directory `%s'", source);
+		dp = opendir(source);
+		if (dp == NULL) {
 			status = -1;
-			goto end;
+			goto preserve_status;
 		}
 
 		while ((d = readdir(dp)) != NULL) {
 			char *new_source, *new_dest;
 
-			if (strcmp(d->d_name, ".") == 0 ||
-					strcmp(d->d_name, "..") == 0)
+			new_source = concat_subpath_file(source, d->d_name);
+			if (new_source == NULL)
 				continue;
-
-			new_source = concat_path_file(source, d->d_name);
 			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 have only EBADF error, but "dp" not changes */
 		closedir(dp);
 
-		if (!dest_exists &&
-				chmod(dest, source_stat.st_mode & ~saved_umask) < 0) {
-			perror_msg("unable to change permissions of `%s'", dest);
+		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 (S_ISREG(source_stat.st_mode)) {
-		FILE *sfp, *dfp=NULL;
-#ifdef CONFIG_FEATURE_PRESERVE_HARDLINKS
-		char *link_name;
 
-		if (!(flags & FILEUTILS_DEREFERENCE) &&
-				is_in_ino_dev_hashtable(&source_stat, &link_name)) {
-			if (link(link_name, dest) < 0) {
-				perror_msg("unable to link `%s'", dest);
+	} 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;
 		}
-#endif
-
-		if ((sfp = wfopen(source, "r")) == NULL) {
-			return -1;
-		}
-
-		if (dest_exists) {
-			if (flags & FILEUTILS_INTERACTIVE) {
-				fprintf(stderr, "%s: overwrite `%s'? ", applet_name, dest);
-				if (!ask_confirmation()) {
-					fclose (sfp);
-					return 0;
-				}
-			}
-
-			if ((dfp = fopen(dest, "w")) == NULL) {
-				if (!(flags & FILEUTILS_FORCE)) {
-					perror_msg("unable to open `%s'", dest);
-					fclose (sfp);
-					return -1;
-				}
+		return 0;
 
-				if (unlink(dest) < 0) {
-					perror_msg("unable to remove `%s'", dest);
-					fclose (sfp);
-					return -1;
+	} 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;
+					}
 				}
-
-				dest_exists = 0;
+				return 0;
 			}
+			// TODO: probably is_in_.. and add_to_...
+			// can be combined: find_or_add_...
+			add_to_ino_dev_hashtable(&source_stat, dest);
 		}
 
-		if (!dest_exists) {
-			int fd;
+		src_fd = open(source, O_RDONLY);
+		if (src_fd == -1) {
+			bb_perror_msg("cannot open '%s'", source);
+			return -1;
+		}
 
-			if ((fd = open(dest, O_WRONLY|O_CREAT, source_stat.st_mode)) < 0 ||
-					(dfp = fdopen(fd, "w")) == NULL) {
-				if (fd >= 0)
-					close(fd);
-				perror_msg("unable to open `%s'", dest);
-				fclose (sfp);
+		// 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 (copy_file_chunk(sfp, dfp, -1) < 0)
+		if (bb_copyfd_eof(src_fd, dst_fd) == -1)
 			status = -1;
-
-		if (fclose(dfp) < 0) {
-			perror_msg("unable to close `%s'", dest);
+		if (close(dst_fd) < 0) {
+			bb_perror_msg("cannot close '%s'", dest);
 			status = -1;
 		}
-
-		if (fclose(sfp) < 0) {
-			perror_msg("unable to close `%s'", source);
+		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)) {
 
-		if (dest_exists &&
-		       ((flags & FILEUTILS_FORCE) == 0 || unlink(dest) < 0)) {
-				perror_msg("unable to remove `%s'", dest);
+	} 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 {
-		error_msg("internal error: unrecognized file type");
-		return -1;
-		}
-	if (S_ISBLK(source_stat.st_mode) || S_ISCHR(source_stat.st_mode) ||
-	    S_ISSOCK(source_stat.st_mode)) {
-		if (mknod(dest, source_stat.st_mode, source_stat.st_rdev) < 0) {
-			perror_msg("unable to create `%s'", dest);
-			return -1;
-		}
-	} else if (S_ISFIFO(source_stat.st_mode)) {
-		if (mkfifo(dest, source_stat.st_mode) < 0) {
-			perror_msg("cannot create fifo `%s'", dest);
-			return -1;
-		}
-	} else if (S_ISLNK(source_stat.st_mode)) {
-		char *lpath;
+		} else if (S_ISLNK(source_stat.st_mode)) {
+			char *lpath;
 
-		lpath = xreadlink(source);
-		if (symlink(lpath, dest) < 0) {
-			perror_msg("cannot create symlink `%s'", dest);
-			return -1;
-		}
-		free(lpath);
+			lpath = xreadlink(source);
+			if (symlink(lpath, dest) < 0) {
+				bb_perror_msg("cannot create symlink '%s'", dest);
+				free(lpath);
+				return -1;
+			}
+			free(lpath);
 
-#if (__GLIBC__ >= 2) && (__GLIBC_MINOR__ >= 1)
-		if (flags & FILEUTILS_PRESERVE_STATUS)
-			if (lchown(dest, source_stat.st_uid, source_stat.st_gid) < 0)
-				perror_msg("unable to preserve ownership of `%s'", dest);
-#endif
+			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);
 
-#ifdef CONFIG_FEATURE_PRESERVE_HARDLINKS
-		add_to_ino_dev_hashtable(&source_stat, dest);
-#endif
+			return 0;
 
-		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;
 	}
 
-#ifdef CONFIG_FEATURE_PRESERVE_HARDLINKS
-	add_to_ino_dev_hashtable(&source_stat, dest);
-#endif
-
-end:
+ preserve_status:
 
-	if (flags & FILEUTILS_PRESERVE_STATUS) {
+	if (flags & FILEUTILS_PRESERVE_STATUS
+	/* Cannot happen: */
+	/* && !(flags & (FILEUTILS_MAKE_SOFTLINK|FILEUTILS_MAKE_HARDLINK)) */
+	) {
 		struct utimbuf times;
 
 		times.actime = source_stat.st_atime;
 		times.modtime = source_stat.st_mtime;
 		if (utime(dest, &times) < 0)
-			perror_msg("unable to preserve times of `%s'", dest);
+			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);
-			perror_msg("unable to preserve ownership of `%s'", dest);
+			bb_perror_msg("cannot preserve %s of '%s'", "ownership", dest);
 		}
 		if (chmod(dest, source_stat.st_mode) < 0)
-			perror_msg("unable to preserve permissions of `%s'", dest);
+			bb_perror_msg("cannot preserve %s of '%s'", "permissions", dest);
 	}
 
 	return status;