fdisk: check returns in fdisk from partition changes

currently the code in fdisk which changes partition types is a bit fragile ...
it assumes the partition type succeeded instead of checking the user input or
for errors.  ive tweaked the sub functions to return a value indicative of the
functions' success and fdisk now checks/reports based on that.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>

5 files changed, 21 insertions, 15 deletions

diff --git a/fdisk/fdisk.c b/fdisk/fdisk.c
index 5010d7db3..f2faa7fbc 100644
--- a/fdisk/fdisk.c
+++ b/fdisk/fdisk.c
@@ -1499,17 +1499,21 @@ change_sysid(void) {
                         if (sys == origsys)
 				break;
 			if (sun_label) {
-				sun_change_sysid(i, sys);
+				ptes[i].changed = sun_change_sysid(i, sys);
 			} else
 			if (sgi_label) {
-				sgi_change_sysid(i, sys);
-			} else
+				ptes[i].changed = sgi_change_sysid(i, sys);
+			} else {
 				p->sys_ind = sys;
-                        printf (_("Changed system type of partition %d "
-                                "to %x (%s)\n"), i + 1, sys,
-                                (temp = partition_type(sys)) ? temp :
-                                _("Unknown"));
-                        ptes[i].changed = 1;
+				ptes[i].changed = 1;
+			}
+			temp = partition_type(sys) ? : _("Unknown");
+			if (ptes[i].changed)
+				printf (_("Changed system type of partition %d "
+				        "to %x (%s)\n"), i + 1, sys, temp);
+			else
+				printf (_("System type of partition %d is unchanged"
+				        "to %x (%s)\n"), i + 1, sys, temp);
 			if (is_dos_partition(origsys) ||
 			    is_dos_partition(sys))
 				dos_changed = 1;
diff --git a/fdisk/fdisksgilabel.c b/fdisk/fdisksgilabel.c
index e1b3829cb..7e189fb3f 100644
--- a/fdisk/fdisksgilabel.c
+++ b/fdisk/fdisksgilabel.c
@@ -537,12 +537,12 @@ verify_sgi(int verbose)
 	return (gap > 0) ? 1 : (gap == 0) ? 0 : -1;
 }
 
-void
+int
 sgi_change_sysid(int i, int sys)
 {
 	if (sgi_get_num_sectors(i) == 0) /* caught already before, ... */ {
 		printf(_("Sorry You may change the Tag of non-empty partitions.\n"));
-		return;
+		return 0;
 	}
 	if (((sys != ENTIRE_DISK) && (sys != SGI_VOLHDR))
 	    && (sgi_get_start_sector(i)<1)) {
@@ -553,9 +553,10 @@ sgi_change_sysid(int i, int sys)
 			  "Only the \"SGI volume\" entire disk section may violate this.\n"
 			  "Type YES if you are sure about tagging this partition differently.\n"));
 		if (strcmp (line_ptr, _("YES\n")))
-			return;
+			return 0;
 	}
 	sgilabel->partitions[i].id = SSWAP32(sys);
+	return 1;
 }
 
 /* returns partition index of first entry marked as entire disk */
diff --git a/fdisk/fdisksgilabel.h b/fdisk/fdisksgilabel.h
index fe757bf1c..02b3e9d55 100644
--- a/fdisk/fdisksgilabel.h
+++ b/fdisk/fdisksgilabel.h
@@ -112,7 +112,7 @@ extern struct	systypes sgi_sys_types[];
 extern void	sgi_nolabel( void );
 extern int	check_sgi_label( void );
 extern void	sgi_list_table( int xtra );
-extern void	sgi_change_sysid( int i, int sys );
+extern int  sgi_change_sysid( int i, int sys );
 extern unsigned int	sgi_get_start_sector( int i );
 extern unsigned int	sgi_get_num_sectors( int i );
 extern int	sgi_get_sysid( int i );
diff --git a/fdisk/fdisksunlabel.c b/fdisk/fdisksunlabel.c
index f67aa261a..60ade06d5 100644
--- a/fdisk/fdisksunlabel.c
+++ b/fdisk/fdisksunlabel.c
@@ -530,7 +530,7 @@ void sun_delete_partition(int i)
 	part->num_sectors = 0;
 }
 
-void sun_change_sysid(int i, __u16 sys)
+int sun_change_sysid(int i, __u16 sys)
 {
 	struct sun_partition *part = &sunlabel->partitions[i];
 	struct sun_tag_flag *tag = &sunlabel->part_tags[i];
@@ -543,7 +543,7 @@ void sun_change_sysid(int i, __u16 sys)
 	      "Type YES if you're very sure you would like that partition\n"
 	      "tagged with 82 (Linux swap): "));
 	    if (strcmp (line_ptr, _("YES\n")))
-		    return;
+		    return 0;
 	}
 	switch (sys) {
 	case SUN_TAG_SWAP:
@@ -558,6 +558,7 @@ void sun_change_sysid(int i, __u16 sys)
 		break;
 	}
 	tag->tag = SSWAP16(sys);
+	return 1;
 }
 
 void sun_list_table(int xtra)
diff --git a/fdisk/fdisksunlabel.h b/fdisk/fdisksunlabel.h
index c8e069804..fba67f725 100644
--- a/fdisk/fdisksunlabel.h
+++ b/fdisk/fdisksunlabel.h
@@ -82,7 +82,7 @@ extern int check_sun_label(void);
 extern void sun_nolabel(void);
 extern void create_sunlabel(void);
 extern void sun_delete_partition(int i);
-extern void sun_change_sysid(int i, __u16 sys);
+extern int sun_change_sysid(int i, __u16 sys);
 extern void sun_list_table(int xtra);
 extern void verify_sun(void);
 extern void add_sun_partition(int n, int sys);