add wic ln command to create a symbolic link to a file

scripts/lib/wic/engine.py

@@ -354,6 +354,23 @@ def copy(self, src, dest):
         exec_cmd(cmd, as_shell=True)
         self._put_part_image(pnum)
 
+    def link(self, src, dest):
+        """Create a symbolic link to a file in wic image."""
+        pnum =  dest.part
+
+        if pnum not in self.partitions:
+            raise WicError("Partition %s is not in the image" % pnum)
+
+        if self.partitions[pnum].fstype.startswith('ext'):
+            cmd = "printf 'cd {}\nsymlink {} {}\n' | {} -w {}".\
+                format(os.path.dirname(dest.path), os.path.basename(src),
+                    src, self.debugfs, self._get_part_image(pnum))
+        else: # fat
+            print("Not support the fat file system!")
+
+        exec_cmd(cmd, as_shell=True)
+        self._put_part_image(pnum)
+
     def remove_ext(self, pnum, path, recursive):
         """
         Remove files/dirs and their contents from the partition.
@@ -579,6 +596,13 @@ def wic_cp(args, native_sysroot):
         disk = Disk(args.dest.image, native_sysroot)
     disk.copy(args.src, args.dest)
 
+def wic_ln(args, native_sysroot):
+    """
+    Create file's Symbolic link in ext partition of
+    partitioned image.
+    """
+    disk = Disk(args.dest.image, native_sysroot)
+    disk.link(args.src, args.dest)
 
 def wic_rm(args, native_sysroot):
     """

scripts/lib/wic/help.py

@@ -274,6 +274,49 @@ def invoke_subcommand(args, parser, main_command_usage, subcommands):
     details.
 """
 
+wic_ln_usage = """
+
+ Create a symboilic link to a file or dir in partitioned image
+
+ usage: wic ln <path> <image>:<ext* partition><path>
+
+ This command  a symbolic link to a file or dir in ext* partitions.
+
+ See 'wic help ls' for more detailed instructions.
+
+"""
+
+wic_ln_help = """
+
+NAME
+    wic ln - Create a symboilic link to a file or dir in partitioned image
+
+SYNOPSIS
+    wic ln <file> <image>:<ext* partition><path>
+    wic ln <file> <image>:<ext* partition><path> --native-sysroot <path>
+
+DESCRIPTION
+    This command  a symbolic link to a file or dir in ext* partitions.
+
+    For example:
+        $ wic ls test.rootfs.wic:2/bin/ | grep sdbus
+
+        $ wic ls test.rootfs.wic:2/usr/bin/ | grep sdbus
+            6224  100775 (1)      0      0   61536 30-Mar-2023 14:45 sdbus-service
+            6255  100775 (1)      0      0   42352 29-Mar-2023 13:42 sdbus-client
+            6269  100775 (1)      0      0   19848 29-Mar-2023 10:52 sdbus-demo
+
+        To create a symbolic link
+        $ wic ln /usr/bin/sdbus-service test.rootfs.wic:2/bin/
+
+        $ wic ls test.rootfs.wic:2/bin/ | grep sdbus
+           6254  120777 (7)      0      0      22  6-May-2023 10:44 sdbus-service
+
+    The -n option is used to specify the path to the native sysroot
+    containing the tools(parted and mtools) to use.
+
+"""
+
 wic_ls_usage = """
 
  List content of a partitioned image
@@ -1108,6 +1151,7 @@ class (see the SourcePlugin source for details):
 
     list   -   List available canned images and source plugins
     ls     -   List contents of partitioned image or partition
+    ln     -   Create a symbolic link to a file in ext* partitions
     rm     -   Remove files or directories from the vfat or ext* partitions
     help   -   Show help for a wic COMMAND or TOPIC
     write  -   Write an image to a device

scripts/wic

@@ -231,6 +231,12 @@ def wic_list_subcommand(args, usage_str):
     if not engine.wic_list(args, scripts_path):
         raise WicError("Bad list arguments, exiting")
 
+def wic_ln_subcommand(args, usage_str):
+    """
+    Command-line handling for creating a symbilic link to a file/dir in images.
+    The real work is done by engine.wic_ln()
+    """
+    engine.wic_ln(args, args.native_sysroot)
 
 def wic_ls_subcommand(args, usage_str):
     """
@@ -292,6 +298,9 @@ helptopics = {
     "create":    [wic_help_topic_subcommand,
                   wic_help_topic_usage,
                   hlp.wic_create_help],
+    "ln":        [wic_help_topic_subcommand,
+                  wic_help_topic_usage,
+                  hlp.wic_ln_help],
     "ls":        [wic_help_topic_subcommand,
                   wic_help_topic_usage,
                   hlp.wic_ls_help],
@@ -391,6 +400,14 @@ def wic_init_parser_ls(subparser):
     subparser.add_argument("-n", "--native-sysroot",
                         help="path to the native sysroot containing the tools")
 
+def wic_init_parser_ln(subparser):
+    subparser.add_argument("src",
+                        help="<file>")
+    subparser.add_argument("dest",
+                        help="image spec: <image>:<ext* partition>[<path>]")
+    subparser.add_argument("-n", "--native-sysroot",
+                        help="path to the native sysroot containing the tools")
+
 def imgpathtype(arg):
     img = imgtype(arg)
     if img.part is None:
@@ -471,6 +488,10 @@ subcommands = {
                   hlp.wic_list_usage,
                   hlp.wic_list_help,
                   wic_init_parser_list],
+    "ln":        [wic_ln_subcommand,
+                  hlp.wic_ln_usage,
+                  hlp.wic_ln_help,
+                  wic_init_parser_ln],
     "ls":        [wic_ls_subcommand,
                   hlp.wic_ls_usage,
                   hlp.wic_ls_help,
@@ -538,6 +559,11 @@ def main(argv):
             args.src = imgtype(args.src)
         else:
             raise argparse.ArgumentTypeError("no image or partition number specified.")
+    elif args.command == "ln":
+        if ":" in args.dest:
+            args.dest = imgtype(args.dest)
+        else:
+            raise argparse.ArgumentTypeError("no image or partition number specified.")
 
     return hlp.invoke_subcommand(args, parser, hlp.wic_help_usage, subcommands)