[SeaBIOS] [PATCH v2 1/3] add smbios_locate_uuid() helper function

[Laszlo Ersek]

Signed-off-by: Laszlo Ersek <lersek at redhat.com>
---
 src/smbios.h |    1 +
 src/smbios.c |   47 +++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 48 insertions(+), 0 deletions(-)

diff --git a/src/smbios.h b/src/smbios.h
index 9d54e80..c1fe7f6 100644
--- a/src/smbios.h
+++ b/src/smbios.h
@@ -165,4 +165,5 @@ struct smbios_type_127 {
     struct smbios_structure_header header;
 } PACKED;
 
+const u8 *smbios_locate_uuid(const struct smbios_entry_point *ep);
 #endif // smbios.h
diff --git a/src/smbios.c b/src/smbios.c
index fc84aad..5874bec 100644
--- a/src/smbios.c
+++ b/src/smbios.c
@@ -521,3 +521,50 @@ smbios_init(void)
     smbios_entry_point_init(max_struct_size, p - start, start, nr_structs);
     free(start);
 }
+
+const u8 *
+smbios_locate_uuid(const struct smbios_entry_point *ep)
+{
+    u32 addr, end;
+
+    if (ep == NULL)
+        return NULL;
+
+    addr =        ep->structure_table_address;
+    end  = addr + ep->structure_table_length;
+
+    /* the following takes care of any initial wraparound too */
+    while (addr < end) {
+        const struct smbios_structure_header *hdr;
+
+        /* partial structure header */
+        if (end - addr < sizeof(struct smbios_structure_header))
+            return NULL;
+
+        hdr = (struct smbios_structure_header *)addr;
+
+        /* partial structure */
+        if (end - addr < hdr->length)
+            return NULL;
+
+        /* any Type 1 structure version will do that has the UUID */
+        if (hdr->type == 1 &&
+            hdr->length >= offsetof(struct smbios_type_1, uuid) + 16)
+            return (u8 *)(addr + offsetof(struct smbios_type_1, uuid));
+
+        /* done with formatted area, skip string-set */
+        addr += hdr->length;
+
+        while (end - addr >= 2 &&
+               (*(u8 *)addr     != '\0' ||
+                *(u8 *)(addr+1) != '\0'))
+            ++addr;
+
+        /* structure terminator not found */
+        if (end - addr < 2)
+            return NULL;
+
+        addr += 2;
+    }
+    return NULL;
+}
-- 
1.7.1