chain.c32, libcom32: Move struct gpt as disk_gpt_header

Also moved gpt_sig_magic as disk_gpt_sig_magic.
Moving portions of chain.c32 into libcom32.

Signed-off-by: Shao Miller <shao.miller@yrdsb.edu.on.ca>

2 files changed, 35 insertions, 33 deletions

diff --git a/com32/include/syslinux/disk.h b/com32/include/syslinux/disk.h
index 7c4e276f..37641d06 100644
--- a/com32/include/syslinux/disk.h
+++ b/com32/include/syslinux/disk.h
@@ -112,6 +112,33 @@ struct disk_gpt_part_entry {
     char name[72];
 } __attribute__ ((packed));
 
+/* A GPT header */
+struct disk_gpt_header {
+    char sig[8];
+    union {
+	struct {
+	    uint16_t minor;
+	    uint16_t major;
+	} fields __attribute__ ((packed));
+	uint32_t uint32;
+	char raw[4];
+    } rev __attribute__ ((packed));
+    uint32_t hdr_size;
+    uint32_t chksum;
+    char reserved1[4];
+    uint64_t lba_cur;
+    uint64_t lba_alt;
+    uint64_t lba_first_usable;
+    uint64_t lba_last_usable;
+    struct guid disk_guid;
+    uint64_t lba_table;
+    uint32_t part_count;
+    uint32_t part_size;
+    uint32_t table_chksum;
+    char reserved2[1];
+} __attribute__ ((packed));
+static const char disk_gpt_sig_magic[] = "EFI PART";
+
 extern int disk_int13_retry(const com32sys_t * inreg, com32sys_t * outreg);
 extern int disk_get_params(int disk, struct disk_info *const diskinfo);
 extern void *disk_read_sectors(const struct disk_info *const diskinfo,
diff --git a/com32/modules/chain.c b/com32/modules/chain.c
index f69c9bd5..a703ea09 100644
--- a/com32/modules/chain.c
+++ b/com32/modules/chain.c
@@ -348,35 +348,8 @@ err_alloc:
     return NULL;
 }
 
-/* A GPT header */
-struct gpt {
-    char sig[8];
-    union {
-	struct {
-	    uint16_t minor;
-	    uint16_t major;
-	} fields __attribute__ ((packed));
-	uint32_t uint32;
-	char raw[4];
-    } rev __attribute__ ((packed));
-    uint32_t hdr_size;
-    uint32_t chksum;
-    char reserved1[4];
-    uint64_t lba_cur;
-    uint64_t lba_alt;
-    uint64_t lba_first_usable;
-    uint64_t lba_last_usable;
-    struct guid disk_guid;
-    uint64_t lba_table;
-    uint32_t part_count;
-    uint32_t part_size;
-    uint32_t table_chksum;
-    char reserved2[1];
-} __attribute__ ((packed));
-static const char gpt_sig_magic[] = "EFI PART";
-
 #if DEBUG
-static void gpt_dump(const struct gpt *gpt)
+static void gpt_dump(const struct disk_gpt_header *gpt)
 {
     char guid_text[37];
 
@@ -448,7 +421,7 @@ err_last:
 
 static struct disk_part_iter *get_first_partition(struct disk_part_iter *part)
 {
-    const struct gpt *gpt_candidate;
+    const struct disk_gpt_header *gpt_candidate;
 
     /*
      * Ignore any passed partition iterator.  The caller should
@@ -476,8 +449,9 @@ static struct disk_part_iter *get_first_partition(struct disk_part_iter *part)
     part->private.mbr_index = -1;
     part->next = next_mbr_part;
     /* Check for a GPT disk */
-    gpt_candidate = (const struct gpt *)(part->block + SECTOR);
-    if (!memcmp(gpt_candidate->sig, gpt_sig_magic, sizeof(gpt_sig_magic))) {
+    gpt_candidate = (const struct disk_gpt_header *)(part->block + SECTOR);
+    if (!memcmp
+	(gpt_candidate->sig, disk_gpt_sig_magic, sizeof(disk_gpt_sig_magic))) {
 	/* LBA for partition table */
 	uint64_t lba_table;
 
@@ -537,14 +511,15 @@ static int find_by_guid(const struct guid *gpt_guid,
 {
     int drive;
     bool is_me;
-    struct gpt *header;
+    struct disk_gpt_header *header;
 
     for (drive = 0x80; drive <= 0xff; drive++) {
 	if (disk_get_params(drive, &diskinfo))
 	    continue;		/* Drive doesn't exist */
 	if (!(header = disk_read_sectors(&diskinfo, 1, 1)))
 	    continue;		/* Cannot read sector */
-	if (memcmp(&header->sig, gpt_sig_magic, sizeof(gpt_sig_magic))) {
+	if (memcmp
+	    (&header->sig, disk_gpt_sig_magic, sizeof(disk_gpt_sig_magic))) {
 	    /* Not a GPT disk */
 	    free(header);
 	    continue;