dissect: add an API that can read various metadata bits out of a dissected image

We focus on four kinds of metadata:

1. /etc/hostname
2. /etc/machine-id
3. /etc/machine-info
4. /etc/os-release or /usr/lib/os-release

This makes dissected images nicely self-contained as we can figure out
what they are just by dissecting them.

1 files changed, 8 insertions, 0 deletions

diff --git a/src/shared/dissect-image.h b/src/shared/dissect-image.h
index 20afbb5bf6..30a12cb540 100644
--- a/src/shared/dissect-image.h
+++ b/src/shared/dissect-image.h
@@ -77,7 +77,13 @@ struct DissectedImage {
         bool encrypted:1;
         bool verity:1;     /* verity available and usable */
         bool can_verity:1; /* verity available, but not necessarily used */
+
         DissectedPartition partitions[_PARTITION_DESIGNATOR_MAX];
+
+        char *hostname;
+        sd_id128_t machine_id;
+        char **machine_info;
+        char **os_release;
 };
 
 int dissect_image(int fd, const void *root_hash, size_t root_hash_size, DissectImageFlags flags, DissectedImage **ret);
@@ -89,6 +95,8 @@ int dissected_image_decrypt(DissectedImage *m, const char *passphrase, const voi
 int dissected_image_decrypt_interactively(DissectedImage *m, const char *passphrase, const void *root_hash, size_t root_hash_size, DissectImageFlags flags, DecryptedImage **ret);
 int dissected_image_mount(DissectedImage *m, const char *dest, DissectImageFlags flags);
 
+int dissected_image_acquire_metadata(DissectedImage *m);
+
 DecryptedImage* decrypted_image_unref(DecryptedImage *p);
 DEFINE_TRIVIAL_CLEANUP_FUNC(DecryptedImage*, decrypted_image_unref);
 int decrypted_image_relinquish(DecryptedImage *d);