make rsync behave more like GNU cp with regard to file permissions

when -p (preserve permissions) isn't set.

It works by taking the sending file permissions and masking them with
the umask to create the destination file permissions. (There is really
no "correct" way of doing this but at least we now behave like GNU cp
which fits the principle of least surprise.)

also fixed a race condition in copy_file()

1 files changed, 166 insertions, 159 deletions

diff --git a/flist.c b/flist.c
index 78b2c859..c33323ed 100644
--- a/flist.c
+++ b/flist.c
@@ -94,95 +94,95 @@ static char *flist_dir;
 
 void send_file_entry(struct file_struct *file,int f,unsigned base_flags)
 {
-  unsigned char flags;
-  static time_t last_time;
-  static mode_t last_mode;
-  static dev_t last_rdev;
-  static uid_t last_uid;
-  static gid_t last_gid;
-  static char lastname[MAXPATHLEN];
-  char *fname;
-  int l1,l2;
-
-  if (f == -1) return;
-
-  if (!file) {
-    write_byte(f,0);
-    return;
-  }
+	unsigned char flags;
+	static time_t last_time;
+	static mode_t last_mode;
+	static dev_t last_rdev;
+	static uid_t last_uid;
+	static gid_t last_gid;
+	static char lastname[MAXPATHLEN];
+	char *fname;
+	int l1,l2;
+
+	if (f == -1) return;
+
+	if (!file) {
+		write_byte(f,0);
+		return;
+	}
 
-  fname = f_name(file);
-
-  flags = base_flags;
-
-  if (file->mode == last_mode) flags |= SAME_MODE;
-  if (file->rdev == last_rdev) flags |= SAME_RDEV;
-  if (file->uid == last_uid) flags |= SAME_UID;
-  if (file->gid == last_gid) flags |= SAME_GID;
-  if (file->modtime == last_time) flags |= SAME_TIME;
-
-  for (l1=0;lastname[l1] && (fname[l1] == lastname[l1]) && (l1 < 255);l1++) ;  
-  l2 = strlen(fname) - l1;
-
-  if (l1 > 0) flags |= SAME_NAME;
-  if (l2 > 255) flags |= LONG_NAME;
-
-  /* we must make sure we don't send a zero flags byte or the other
-     end will terminate the flist transfer */
-  if (flags == 0 && !S_ISDIR(file->mode)) flags |= FLAG_DELETE;
-  if (flags == 0) flags |= LONG_NAME;
-
-  write_byte(f,flags);  
-  if (flags & SAME_NAME)
-    write_byte(f,l1);
-  if (flags & LONG_NAME)
-    write_int(f,l2);
-  else
-    write_byte(f,l2);
-  write_buf(f,fname+l1,l2);
-
-  write_longint(f,file->length);
-  if (!(flags & SAME_TIME))
-    write_int(f,(int)file->modtime);
-  if (!(flags & SAME_MODE))
-    write_int(f,(int)file->mode);
-  if (preserve_uid && !(flags & SAME_UID)) {
-	  add_uid(file->uid);
-	  write_int(f,(int)file->uid);
-  }
-  if (preserve_gid && !(flags & SAME_GID)) {
-	  add_gid(file->gid);
-	  write_int(f,(int)file->gid);
-  }
-  if (preserve_devices && IS_DEVICE(file->mode) && !(flags & SAME_RDEV))
-    write_int(f,(int)file->rdev);
+	fname = f_name(file);
+
+	flags = base_flags;
+
+	if (file->mode == last_mode) flags |= SAME_MODE;
+	if (file->rdev == last_rdev) flags |= SAME_RDEV;
+	if (file->uid == last_uid) flags |= SAME_UID;
+	if (file->gid == last_gid) flags |= SAME_GID;
+	if (file->modtime == last_time) flags |= SAME_TIME;
+
+	for (l1=0;lastname[l1] && (fname[l1] == lastname[l1]) && (l1 < 255);l1++) ;  
+	l2 = strlen(fname) - l1;
+
+	if (l1 > 0) flags |= SAME_NAME;
+	if (l2 > 255) flags |= LONG_NAME;
+
+	/* we must make sure we don't send a zero flags byte or the other
+	   end will terminate the flist transfer */
+	if (flags == 0 && !S_ISDIR(file->mode)) flags |= FLAG_DELETE;
+	if (flags == 0) flags |= LONG_NAME;
+
+	write_byte(f,flags);  
+	if (flags & SAME_NAME)
+		write_byte(f,l1);
+	if (flags & LONG_NAME)
+		write_int(f,l2);
+	else
+		write_byte(f,l2);
+	write_buf(f,fname+l1,l2);
+
+	write_longint(f,file->length);
+	if (!(flags & SAME_TIME))
+		write_int(f,(int)file->modtime);
+	if (!(flags & SAME_MODE))
+		write_int(f,(int)file->mode);
+	if (preserve_uid && !(flags & SAME_UID)) {
+		add_uid(file->uid);
+		write_int(f,(int)file->uid);
+	}
+	if (preserve_gid && !(flags & SAME_GID)) {
+		add_gid(file->gid);
+		write_int(f,(int)file->gid);
+	}
+	if (preserve_devices && IS_DEVICE(file->mode) && !(flags & SAME_RDEV))
+		write_int(f,(int)file->rdev);
 
 #if SUPPORT_LINKS
-  if (preserve_links && S_ISLNK(file->mode)) {
-    write_int(f,strlen(file->link));
-    write_buf(f,file->link,strlen(file->link));
-  }
+	if (preserve_links && S_ISLNK(file->mode)) {
+		write_int(f,strlen(file->link));
+		write_buf(f,file->link,strlen(file->link));
+	}
 #endif
 
 #if SUPPORT_HARD_LINKS
-  if (preserve_hard_links && S_ISREG(file->mode)) {
-    write_int(f,(int)file->dev);
-    write_int(f,(int)file->inode);
-  }
+	if (preserve_hard_links && S_ISREG(file->mode)) {
+		write_int(f,(int)file->dev);
+		write_int(f,(int)file->inode);
+	}
 #endif
 
-  if (always_checksum) {
-	  write_buf(f,file->sum,csum_length);
-  }       
+	if (always_checksum) {
+		write_buf(f,file->sum,csum_length);
+	}       
 
-  last_mode = file->mode;
-  last_rdev = file->rdev;
-  last_uid = file->uid;
-  last_gid = file->gid;
-  last_time = file->modtime;
+	last_mode = file->mode;
+	last_rdev = file->rdev;
+	last_uid = file->uid;
+	last_gid = file->gid;
+	last_time = file->modtime;
 
-  strlcpy(lastname,fname,MAXPATHLEN-1);
-  lastname[MAXPATHLEN-1] = 0;
+	strlcpy(lastname,fname,MAXPATHLEN-1);
+	lastname[MAXPATHLEN-1] = 0;
 }
 
 
@@ -190,101 +190,108 @@ void send_file_entry(struct file_struct *file,int f,unsigned base_flags)
 static void receive_file_entry(struct file_struct **fptr,
 			       unsigned flags,int f)
 {
-  static time_t last_time;
-  static mode_t last_mode;
-  static dev_t last_rdev;
-  static uid_t last_uid;
-  static gid_t last_gid;
-  static char lastname[MAXPATHLEN];
-  char thisname[MAXPATHLEN];
-  int l1=0,l2=0;
-  char *p;
-  struct file_struct *file;
+	static time_t last_time;
+	static mode_t last_mode;
+	static dev_t last_rdev;
+	static uid_t last_uid;
+	static gid_t last_gid;
+	static char lastname[MAXPATHLEN];
+	char thisname[MAXPATHLEN];
+	int l1=0,l2=0;
+	char *p;
+	struct file_struct *file;
 
-  if (flags & SAME_NAME)
-    l1 = read_byte(f);
+	if (flags & SAME_NAME)
+		l1 = read_byte(f);
   
-  if (flags & LONG_NAME)
-    l2 = read_int(f);
-  else
-    l2 = read_byte(f);
+	if (flags & LONG_NAME)
+		l2 = read_int(f);
+	else
+		l2 = read_byte(f);
 
-  file = (struct file_struct *)malloc(sizeof(*file));
-  if (!file) out_of_memory("receive_file_entry");
-  memset((char *)file, 0, sizeof(*file));
-  (*fptr) = file;
+	file = (struct file_struct *)malloc(sizeof(*file));
+	if (!file) out_of_memory("receive_file_entry");
+	memset((char *)file, 0, sizeof(*file));
+	(*fptr) = file;
 
-  if (l2 >= MAXPATHLEN-l1) overflow("receive_file_entry");
+	if (l2 >= MAXPATHLEN-l1) overflow("receive_file_entry");
 
-  strlcpy(thisname,lastname,l1);
-  read_sbuf(f,&thisname[l1],l2);
-  thisname[l1+l2] = 0;
+	strlcpy(thisname,lastname,l1);
+	read_sbuf(f,&thisname[l1],l2);
+	thisname[l1+l2] = 0;
 
-  strlcpy(lastname,thisname,MAXPATHLEN-1);
-  lastname[MAXPATHLEN-1] = 0;
+	strlcpy(lastname,thisname,MAXPATHLEN-1);
+	lastname[MAXPATHLEN-1] = 0;
 
-  clean_fname(thisname);
+	clean_fname(thisname);
 
-  if (relative_paths && thisname[0] == '/') {
-	  /* strip / off absolute paths in destination */
-	  memmove(thisname, thisname+1, strlen(thisname));
-	  if (!thisname[0]) strcpy(thisname,".");
-  }
+	if (relative_paths && thisname[0] == '/') {
+		/* strip / off absolute paths in destination */
+		memmove(thisname, thisname+1, strlen(thisname));
+		if (!thisname[0]) strcpy(thisname,".");
+	}
 
-  if ((p = strrchr(thisname,'/'))) {
-	  static char *lastdir;
-	  *p = 0;
-	  if (lastdir && strcmp(thisname, lastdir)==0) {
-		  file->dirname = lastdir;
-	  } else {
-		  file->dirname = strdup(thisname);
-		  lastdir = file->dirname;
-	  }
-	  file->basename = strdup(p+1);
-  } else {
-	  file->dirname = NULL;
-	  file->basename = strdup(thisname);
-  }
+	if ((p = strrchr(thisname,'/'))) {
+		static char *lastdir;
+		*p = 0;
+		if (lastdir && strcmp(thisname, lastdir)==0) {
+			file->dirname = lastdir;
+		} else {
+			file->dirname = strdup(thisname);
+			lastdir = file->dirname;
+		}
+		file->basename = strdup(p+1);
+	} else {
+		file->dirname = NULL;
+		file->basename = strdup(thisname);
+	}
 
-  if (!file->basename) out_of_memory("receive_file_entry 1");
-
-
-  file->flags = flags;
-  file->length = read_longint(f);
-  file->modtime = (flags & SAME_TIME) ? last_time : (time_t)read_int(f);
-  file->mode = (flags & SAME_MODE) ? last_mode : (mode_t)read_int(f);
-  if (preserve_uid)
-    file->uid = (flags & SAME_UID) ? last_uid : (uid_t)read_int(f);
-  if (preserve_gid)
-    file->gid = (flags & SAME_GID) ? last_gid : (gid_t)read_int(f);
-  if (preserve_devices && IS_DEVICE(file->mode))
-    file->rdev = (flags & SAME_RDEV) ? last_rdev : (dev_t)read_int(f);
-
-  if (preserve_links && S_ISLNK(file->mode)) {
-    int l = read_int(f);
-    file->link = (char *)malloc(l+1);
-    if (!file->link) out_of_memory("receive_file_entry 2");
-    read_sbuf(f,file->link,l);
-  }
+	if (!file->basename) out_of_memory("receive_file_entry 1");
+
+
+	file->flags = flags;
+	file->length = read_longint(f);
+	file->modtime = (flags & SAME_TIME) ? last_time : (time_t)read_int(f);
+	file->mode = (flags & SAME_MODE) ? last_mode : (mode_t)read_int(f);
+	if (preserve_uid)
+		file->uid = (flags & SAME_UID) ? last_uid : (uid_t)read_int(f);
+	if (preserve_gid)
+		file->gid = (flags & SAME_GID) ? last_gid : (gid_t)read_int(f);
+	if (preserve_devices && IS_DEVICE(file->mode))
+		file->rdev = (flags & SAME_RDEV) ? last_rdev : (dev_t)read_int(f);
+
+	if (preserve_links && S_ISLNK(file->mode)) {
+		int l = read_int(f);
+		file->link = (char *)malloc(l+1);
+		if (!file->link) out_of_memory("receive_file_entry 2");
+		read_sbuf(f,file->link,l);
+	}
 
 #if SUPPORT_HARD_LINKS
-  if (preserve_hard_links && S_ISREG(file->mode)) {
-    file->dev = read_int(f);
-    file->inode = read_int(f);
-  }
+	if (preserve_hard_links && S_ISREG(file->mode)) {
+		file->dev = read_int(f);
+		file->inode = read_int(f);
+	}
 #endif
   
-  if (always_checksum) {
-	  file->sum = (char *)malloc(MD4_SUM_LENGTH);
-	  if (!file->sum) out_of_memory("md4 sum");
-	  read_buf(f,file->sum,csum_length);
-  }
+	if (always_checksum) {
+		file->sum = (char *)malloc(MD4_SUM_LENGTH);
+		if (!file->sum) out_of_memory("md4 sum");
+		read_buf(f,file->sum,csum_length);
+	}
   
-  last_mode = file->mode;
-  last_rdev = file->rdev;
-  last_uid = file->uid;
-  last_gid = file->gid;
-  last_time = file->modtime;
+	last_mode = file->mode;
+	last_rdev = file->rdev;
+	last_uid = file->uid;
+	last_gid = file->gid;
+	last_time = file->modtime;
+
+	if (!preserve_perms) {
+		extern int orig_umask;
+		/* set an appropriate set of permissions based on original
+		   permissions and umask. This emulates what GNU cp does */
+		file->mode &= ~orig_umask;
+	}
 }