file: append "target" for symbolic links

When list encounters a symbolic link, we add its nested "target" entry, to where
the symbolic link points. Just how `ls -l` reports.

So when calling e.g.: ubus call file list '{"path":"/etc"}'

instead of:

	...
	"name": "os-release",
	"type": "symlink",
	"size": 21,
	"mode": 41471,
	"atime": 1760891865,
	"mtime": 1760891865,
	"ctime": 1760891865,
	"inode": 266,
	"uid": 0,
	"gid": 0,
	"target_type": "file"
	...

We get:

	...
	"name": "os-release",
	"type": "symlink",
	"size": 21,
	"mode": 41471,
	"atime": 1760891865,
	"mtime": 1760891865,
	"ctime": 1760891865,
	"inode": 266,
	"uid": 0,
	"gid": 0,
	"target": {
		"name": "../usr/lib/os-release",
		"type": "file",
		"size": 582,
		"mode": 33188,
		"atime": 1760891865,
		"mtime": 1760891865,
		"ctime": 1760891865,
		"inode": 1744,
		"uid": 0,
		"gid": 0
	}
	...

And should a link be broken:

	"name": "foo",
	"type": "symlink",
	"size": 8,
	"mode": 41471,
	"atime": 1762640365,
	"mtime": 1762640365,
	"ctime": 1762640365,
	"inode": 348,
	"uid": 0,
	"gid": 0,
	"target": {
		"name": "/tmp/foo",
		"type": "broken"
	}

Tested on: OpenWrt 24.10.4 r28959-29397011cc
Signed-off-by: Paul Donald <newtwen+github@gmail.com>
Tested-by: Eric Fahlgren <ericfahlgren@gmail.com>
Link: https://github.com/openwrt/rpcd/pull/21
Signed-off-by: Robert Marko <robimarko@gmail.com>

1 files changed, 16 insertions, 2 deletions

diff --git a/file.c b/file.c
index dc9c88a..89ba6b4 100644
--- a/file.c
+++ b/file.c
@@ -537,12 +537,26 @@ rpc_file_list(struct ubus_context *ctx, struct ubus_object *obj,
 
 			// add target type only for symlinks
 			if (S_ISLNK(s.st_mode)) {
+				char tbuf[PATH_MAX + 1];
+				ssize_t tlen;
+				void *t;
+
+				// open nested table "target" for symbolic link
+				t = blobmsg_open_table(&buf, "target");
+
+				tlen = readlink(entrypath, tbuf, sizeof(tbuf) - 1);
+				if (tlen >= 0) {
+					tbuf[tlen] = '\0';
+				}
+				blobmsg_add_string(&buf, "name", tbuf);
+
 				struct stat target;
 				if (!stat(entrypath, &target)) {
-					blobmsg_add_string(&buf, "target_type", d_types[_get_stat_type(&target)]);
+					_rpc_file_add_stat(&target);
 				} else {
-					blobmsg_add_string(&buf, "target_type", "broken");
+					blobmsg_add_string(&buf, "type", "broken");
 				}
+				blobmsg_close_table(&buf, t);
 			}
 			blobmsg_close_table(&buf, d);
 		}