[CRIU] [PATCH 12/17] proc_parse: Add parsing of fanotify entries

[Cyrill Gorcunov]

On Mon, Dec 24, 2012 at 05:28:04PM +0400, Pavel Emelyanov wrote:
> 
> Why adding _new_ stuff to parse results in rewriting the _existing_ stuff parsing?

Because of the kernel format specifics -- I've to return the @type of the
parsed entry. Previously we only were carried inotify objects, now I need
to parse fanotify, and adding "call-back" parameters allowed me to unitfy
the code.

I believe you don't like it because of the patch view itself. Here is how
it looks in real


+		if (fdinfo_field(str, "fanotify flags")) {
+			struct fsnotify_params *p = arg;
+
+			if (type != FD_TYPES__FSNOTIFY)
+				goto parse_err;
+
+			ret = sscanf(str, "fanotify flags:%x event-flags:%x",
+				     &p->flags, &p->eflags);
+			if (ret != 2)
+				goto parse_err;
+			entry_met = true;
+			continue;
+		}
+		if (fdinfo_field(str, "inotify wd")	||
+		    fdinfo_field(str, "fanotify ino")	||
+		    fdinfo_field(str, "fanotify mnt_id")) {
 			FhEntry f_handle = FH_ENTRY__INIT;
+			struct fsnotify_params *p = arg;
 			int hoff;
 
 			fsnotify_wd_entry__init(&entry.fsy);
 			entry.fsy.f_handle = &f_handle;
 			entry.fsy.has_type = true;
 
 			if (type != FD_TYPES__FSNOTIFY)
 				goto parse_err;
 
+			entry.fsy.has_type = true;
+			switch (str[9]) {
+			case 'd':
+			case 'i':
+				if (str[9] == 'd') {
+					entry.fsy.type = FSNOTIFY_TYPE__INOTIFY;
+					ret = sscanf(&str[11],
+						     "%x ino:%lx sdev:%x "
+						     "mask:%x ignored_mask:%x "
+						     "fhandle-bytes:%x fhandle-type:%x "
+						     "f_handle: %n",
+						     &entry.fsy.wd, &entry.fsy.i_ino, &entry.fsy.s_dev,
+						     &entry.fsy.mask, &entry.fsy.ignored_mask,
+						     &entry.fsy.f_handle->bytes, &entry.fsy.f_handle->type,
+						     &hoff);
+					if (ret != 7)
+						goto parse_err;
+					hoff += 11;
+				} else {
+					entry.fsy.type = FSNOTIFY_TYPE__FANOTIFY;
+					ret = sscanf(&str[13],
+						     "%lx sdev:%x "
+						     "mflags:%x mask:%x ignored_mask:%x "
+						     "fhandle-bytes:%x fhandle-type:%x "
+						     "f_handle: %n",
+						     &entry.fsy.i_ino, &entry.fsy.s_dev,
+						     &entry.fsy.wd, &entry.fsy.mask, &entry.fsy.ignored_mask,
+						     &entry.fsy.f_handle->bytes, &entry.fsy.f_handle->type,
+						     &hoff);
+					if (ret != 7)
+						goto parse_err;
+					hoff += 13;
+				}
 
+				f_handle.n_handle = FH_ENTRY_SIZES__min_entries;
+				f_handle.handle = xmalloc(pb_repeated_size(&f_handle, handle));
+				if (!f_handle.handle)
+					return -1;
 
+				parse_fhandle_encoded(str + hoff, entry.fsy.f_handle);
+				break;
+			case 'm':
+				/*
+				 * In real it's not @s_dev parsed here but
+				 * @mnt_id. Thus the caller must be ready
+				 * for that and handle this trick accordingly.
+				 */
+				entry.fsy.type = FSNOTIFY_TYPE__FANOTIFY;
+				ret = sscanf(&str[16],
+					     "%x mflags:%x mask:%x ignored_mask:%x",
+					     &entry.fsy.s_dev, &entry.fsy.wd,
+					     &entry.fsy.mask, &entry.fsy.ignored_mask);
+				if (ret != 4)
+					goto parse_err;
+				break;
+			default:
+				BUG();
+				break;
+			}
+
+			ret = cb(&entry, p);
 
 			xfree(f_handle.handle);

	Cyrill