[meta-swupdate][PATCH] Add check for cpio file size limits in swupdate_create_cpio

[Cameron McQuinn]

Currently, `do_swuimage` will fail silently if a file exceeds the 4GB limit imposed by CPIO. This patch adds a check to fail the task if any file exceeds this maximum size.

Signed-off-by: Cameron McQuinn <cameron...@gmail.com>
---
 classes-recipe/swupdate-common.bbclass | 38 ++++++++++++++++++++++++++
 1 file changed, 38 insertions(+)

diff --git a/classes-recipe/swupdate-common.bbclass b/classes-recipe/swupdate-common.bbclass
index 80a5d5b..2925a7c 100644
--- a/classes-recipe/swupdate-common.bbclass
+++ b/classes-recipe/swupdate-common.bbclass
@@ -316,7 +316,45 @@ def swupdate_add_artifacts(d, list_for_cpio):
                 bb.fatal("swupdate cannot find %s image file" % image)
 
 
+def swupdate_check_cpio_file_sizes(d, list_for_cpio):
+    """
+    Fail the task if any file exceeds the cpio CRC 4GB limit.
+    """
+    s = d.getVar('S')
+    max_size = (4 * 1024 * 1024 * 1024) - 1  # 4GB - 1 byte
+
+    oversized = []
+
+    for relpath in list_for_cpio:
+        path = os.path.join(s, relpath)
+
+        if not os.path.exists(path):
+            bb.fatal(f"SWUpdate: file listed for SWU does not exist: {relpath}")
+
+        size = os.stat(path).st_size
+        if size > max_size:
+            oversized.append((relpath, size))
+
+    if oversized:
+        msg = [
+            "SWUpdate image creation failed:",
+            "The following files exceed the 4GB cpio CRC format limit:"
+        ]
+
+        for name, size in oversized:
+            msg.append(f"  - {name}: {size} bytes")
+
+        msg.append(
+            "cpio (SVR4 CRC format) cannot pack files >= 4GB.\n"
+            "Consider splitting the artifact, compressing it, or delivering it via an external handler."
+        )
+
+        bb.fatal("\n".join(msg))
+
 def swupdate_create_cpio(d, swudeploydir, list_for_cpio):
+    # Check sizes
+    swupdate_check_cpio_file_sizes(d, list_for_cpio)
+
     workdir = d.getVar('WORKDIR')
     os.chdir(workdir)
     updateimage = d.getVar('IMAGE_NAME') + '.swu'
--
2.43.0