Handle symlinks

lib/private/modify_mtree.awk

@@ -1,4 +1,25 @@
 # Edits mtree files. See the modify_mtree macro in /lib/tar.bzl.
+function create_map(filename) {
+    for (i in map) delete map[i]
+    while (getline < filename > 0) {
+      if ($0 ~ /type=file/ && $0 ~ /content=/) {
+	  match($0, /content=[^ ]+/)
+	  content_field = substr($0, RSTART, RLENGTH)
+	  split(content_field, parts, "=")
+	  path = parts[2]
+	  map[path] = $1
+        }
+    }
+    close(filename)
+}
+BEGIN {
+    # Here we're setting the filename, but you could pass it as an argument to awk
+    #filename = "bazel-bin/lib/tests/tar/mtree17.spec"
+
+   if (mtree_spec != "") {
+      create_map(mtree_spec)
+   }
+}
 {
     if (strip_prefix != "") {
         if ($1 == strip_prefix) {
@@ -45,5 +66,28 @@
     if (package_dir != "") {
         sub(/^/, package_dir "/")
     }
+    if ($0 ~ /type=file/ && $0 ~ /content=/) {
+	match($0, /content=[^ ]+/)
+	content_field = substr($0, RSTART, RLENGTH)
+	split(content_field, parts, "=")
+	path = parts[2]
+
+	# Resolve the symlink if it exists
+	resolved_path = ""
+	cmd = "readlink -f " path
+	cmd | getline resolved_path
+	close(cmd)
+
+	if (resolved_path) {
+	    if (resolved_path ~ bin_dir) {
+		# Strip down the resolved path to start from bin_dir
+		sub("^.*" bin_dir, bin_dir, resolved_path)
+		if (path != resolved_path) {
+		    # Replace the content field with the new path
+		    $0 = $1 " type=link link=" map[resolved_path]
+		}
+	    }
+	}
+    }
     print;
 }

lib/private/tar.bzl

@@ -451,37 +451,51 @@ def _mtree_mutate_impl(ctx):
         src[DefaultInfo].default_runfiles.files
         for src in ctx.attr.srcs
     ]
-    args = ctx.actions.args()
-    bsdtar = ctx.toolchains[TAR_TOOLCHAIN_TYPE]
-    mtree_generator = ctx.executable.mtree_generator.path
 
     out_mtree = ctx.outputs.out
-    args.add("--input", ctx.file.mtree)
-    args.add("--output", out_mtree)
-    args.add("--bin_dir", ctx.bin_dir.path)
+    env = {
+        "MTREE": ctx.file.mtree.path,
+        "OUT": out_mtree.path,
+        "BIN_DIR": ctx.bin_dir.path,
+    }
 
     if ctx.attr.owner:
-        args.add("--owner", ctx.attr.owner)
+        env["OWNER"] = ctx.attr.owner
     if ctx.attr.ownername:
-        args.add("--ownername", ctx.attr.ownername)
+        env["OWNERNAME"] = ctx.attr.ownername
     if ctx.attr.strip_prefix:
-        args.add("--strip_prefix", ctx.attr.strip_prefix)
+        env["STRIP_PREFIX"] = ctx.attr.strip_prefix
     if ctx.attr.package_dir:
-        args.add("--package_dir", ctx.attr.package_dir)
+        env["PACKAGE_DIR"] = ctx.attr.package_dir
     if ctx.attr.mtime:
-        args.add("--mtime", ctx.attr.mtime)
+        env["MTIME"] = ctx.attr.mtime
 
     #executable = bsdtar.tarinfo.binary,
     inputs = ctx.files.srcs[:]
     inputs.append(ctx.file.mtree)
-    ctx.actions.run(
-        executable = mtree_generator,
-        arguments = [args],
+    inputs.append(ctx.file.awk_script)
+
+    ctx.actions.run_shell(
+        command = """
+        env > /home/ewianda/projects/env
+        awk \
+        -v strip_prefix="$STRIP_PREFIX" \
+        -v package_dir="$PACKAGE_DIR" \
+        -v mtime="$MTIME" \
+        -v owner="$OWNER" \
+        -v ownername="$OWNERNAME" \
+        -v bin_dir="$BIN_DIR" \
+        -v mtree_spec="$MTREE" \
+        -f {awk_script} {mtree} > {out}
+        """.format(
+            awk_script = ctx.file.awk_script.path,
+            mtree = ctx.file.mtree.path,
+            out = out_mtree.path,
+        ),
+        env = env,
         inputs = depset(
             direct = inputs,
-            transitive = srcs_runfiles + [
-                ctx.attr.mtree_generator.default_runfiles.files,
-            ],
+            transitive = srcs_runfiles,
         ),
         outputs = [out_mtree],
     )
@@ -500,11 +514,6 @@ mtree_mutate = rule(
         "owner": attr.string(),
         "ownername": attr.string(),
         "out": attr.output(),
-        "mtree_generator": attr.label(
-            default = Label("//tools/mtree:mtree"),
-            executable = True,
-            cfg = "exec",
-        ),
     },
     toolchains = [
         TAR_TOOLCHAIN_TYPE,