libfdisk: Accept negative numbers for last sector input

[kzak@redhat.com: - add note to the man page
                  - add '-' to the dialog query
                  - cleanup functions names and libfdisk.sym]

Signed-off-by: Karel Zak <kzak@redhat.com>

9 files changed, 45 insertions, 7 deletions

diff --git a/libfdisk/src/ask.c b/libfdisk/src/ask.c
index babe040ad..9fabc99c8 100644
--- a/libfdisk/src/ask.c
+++ b/libfdisk/src/ask.c
@@ -320,6 +320,24 @@ int fdisk_ask_number_is_relative(struct fdisk_ask *ask)
 }
 
 /**
+ * fdisk_ask_number_is_wrap_negative:
+ * @ask: ask instance
+ *
+ * The wrap-negative flag allows to accept negative number from user. In this
+ * case the dialog result is calculated as "high - num" (-N from high limit).
+ *
+ * Returns: 1 or 0.
+ *
+ * Since: 2.33
+ */
+int fdisk_ask_number_is_wrap_negative(struct fdisk_ask *ask)
+{
+	assert(ask);
+	assert(is_number_ask(ask));
+	return ask->data.num.wrap_negative;
+}
+
+/**
  * fdisk_ask_number_set_relative
  * @ask: ask instance
  * @relative: 0 or 1
@@ -354,6 +372,13 @@ int fdisk_ask_number_inchars(struct fdisk_ask *ask)
 	return ask->data.num.inchars;
 }
 
+int fdisk_ask_number_set_wrap_negative(struct fdisk_ask *ask, int wrap_negative)
+{
+	assert(ask);
+	ask->data.num.wrap_negative = wrap_negative ? 1 : 0;
+	return 0;
+}
+
 /*
  * Generates string with list ranges (e.g. 1,2,5-8) for the 'cur'
  */
diff --git a/libfdisk/src/bsd.c b/libfdisk/src/bsd.c
index 9ba3140f1..90b44b963 100644
--- a/libfdisk/src/bsd.c
+++ b/libfdisk/src/bsd.c
@@ -288,12 +288,12 @@ static int bsd_add_partition(struct fdisk_context *cxt,
 		fdisk_ask_set_type(ask, FDISK_ASKTYPE_OFFSET);
 
 		if (fdisk_use_cylinders(cxt)) {
-			fdisk_ask_set_query(ask, _("Last cylinder, +cylinders or +size{K,M,G,T,P}"));
+			fdisk_ask_set_query(ask, _("Last cylinder, +/-cylinders or +/-size{K,M,G,T,P}"));
 			fdisk_ask_number_set_unit(ask,
 				     cxt->sector_size *
 				     fdisk_get_units_per_sector(cxt));
 		} else {
-			fdisk_ask_set_query(ask, _("Last sector, +sectors or +size{K,M,G,T,P}"));
+			fdisk_ask_set_query(ask, _("Last sector, +/-sectors or +/-size{K,M,G,T,P}"));
 			fdisk_ask_number_set_unit(ask,cxt->sector_size);
 		}
 
@@ -301,6 +301,7 @@ static int bsd_add_partition(struct fdisk_context *cxt,
 		fdisk_ask_number_set_default(ask, fdisk_cround(cxt, end));
 		fdisk_ask_number_set_high(ask, fdisk_cround(cxt, end));
 		fdisk_ask_number_set_base(ask, fdisk_cround(cxt, begin));
+		fdisk_ask_number_set_wrap_negative(ask, 1); /* wrap negative around high */
 
 		rc = fdisk_do_ask(cxt, ask);
 		end = fdisk_ask_number_get_result(ask);
diff --git a/libfdisk/src/dos.c b/libfdisk/src/dos.c
index f73516460..2e46aca70 100644
--- a/libfdisk/src/dos.c
+++ b/libfdisk/src/dos.c
@@ -1210,12 +1210,12 @@ static int add_partition(struct fdisk_context *cxt, size_t n,
 			fdisk_ask_set_type(ask, FDISK_ASKTYPE_OFFSET);
 
 			if (fdisk_use_cylinders(cxt)) {
-				fdisk_ask_set_query(ask, _("Last cylinder, +cylinders or +size{K,M,G,T,P}"));
+				fdisk_ask_set_query(ask, _("Last cylinder, +/-cylinders or +/-size{K,M,G,T,P}"));
 				fdisk_ask_number_set_unit(ask,
 					     cxt->sector_size *
 					     fdisk_get_units_per_sector(cxt));
 			} else {
-				fdisk_ask_set_query(ask, _("Last sector, +sectors or +size{K,M,G,T,P}"));
+				fdisk_ask_set_query(ask, _("Last sector, +/-sectors or +/-size{K,M,G,T,P}"));
 				fdisk_ask_number_set_unit(ask,cxt->sector_size);
 			}
 
@@ -1223,6 +1223,7 @@ static int add_partition(struct fdisk_context *cxt, size_t n,
 			fdisk_ask_number_set_default(ask, fdisk_cround(cxt, limit));
 			fdisk_ask_number_set_high(ask, fdisk_cround(cxt, limit));
 			fdisk_ask_number_set_base(ask, fdisk_cround(cxt, start));	/* base for relative input */
+			fdisk_ask_number_set_wrap_negative(ask, 1); /* wrap negative around high */
 
 			rc = fdisk_do_ask(cxt, ask);
 			if (rc)
diff --git a/libfdisk/src/fdiskP.h b/libfdisk/src/fdiskP.h
index e7c264edc..bf2f60e08 100644
--- a/libfdisk/src/fdiskP.h
+++ b/libfdisk/src/fdiskP.h
@@ -337,7 +337,8 @@ struct fdisk_ask {
 			uint64_t	unit;		/* unit for offsets */
 			const char	*range;		/* by library generated list */
 			unsigned int	relative :1,
-					inchars  :1;
+					inchars  :1,
+					wrap_negative	:1;
 		} num;
 		/* FDISK_ASKTYPE_{WARN,WARNX,..} */
 		struct ask_print {
@@ -491,6 +492,7 @@ int fdisk_ask_number_set_high(struct fdisk_ask *ask, uint64_t high);
 int fdisk_ask_number_set_base(struct fdisk_ask *ask, uint64_t base);
 int fdisk_ask_number_set_unit(struct fdisk_ask *ask, uint64_t unit);
 int fdisk_ask_number_is_relative(struct fdisk_ask *ask);
+int fdisk_ask_number_set_wrap_negative(struct fdisk_ask *ask, int wrap_negative);
 int fdisk_ask_menu_set_default(struct fdisk_ask *ask, int dfl);
 int fdisk_ask_menu_add_item(struct fdisk_ask *ask, int key,
 			const char *name, const char *desc);
diff --git a/libfdisk/src/gpt.c b/libfdisk/src/gpt.c
index 1ceb4f571..d1d0c434d 100644
--- a/libfdisk/src/gpt.c
+++ b/libfdisk/src/gpt.c
@@ -2444,13 +2444,14 @@ static int gpt_add_partition(
 			if (!ask)
 				return -ENOMEM;
 
-			fdisk_ask_set_query(ask, _("Last sector, +sectors or +size{K,M,G,T,P}"));
+			fdisk_ask_set_query(ask, _("Last sector, +/-sectors or +/-size{K,M,G,T,P}"));
 			fdisk_ask_set_type(ask, FDISK_ASKTYPE_OFFSET);
 			fdisk_ask_number_set_low(ask,     user_f);	/* minimal */
 			fdisk_ask_number_set_default(ask, dflt_l);	/* default */
 			fdisk_ask_number_set_high(ask,    dflt_l);	/* maximal */
 			fdisk_ask_number_set_base(ask,    user_f);	/* base for relative input */
 			fdisk_ask_number_set_unit(ask,    cxt->sector_size);
+			fdisk_ask_number_set_wrap_negative(ask, 1);	/* wrap negative around high */
 
 			rc = fdisk_do_ask(cxt, ask);
 			if (rc)
diff --git a/libfdisk/src/libfdisk.h.in b/libfdisk/src/libfdisk.h.in
index 0c312c3e1..0f8ecd96f 100644
--- a/libfdisk/src/libfdisk.h.in
+++ b/libfdisk/src/libfdisk.h.in
@@ -794,6 +794,7 @@ int fdisk_ask_number_set_result(struct fdisk_ask *ask, uint64_t result);
 uint64_t fdisk_ask_number_get_base(struct fdisk_ask *ask);
 uint64_t fdisk_ask_number_get_unit(struct fdisk_ask *ask);
 int fdisk_ask_number_set_relative(struct fdisk_ask *ask, int relative);
+int fdisk_ask_number_is_wrap_negative(struct fdisk_ask *ask);
 int fdisk_ask_number_inchars(struct fdisk_ask *ask);
 int fdisk_ask_partnum(struct fdisk_context *cxt, size_t *partnum, int wantnew);
 
diff --git a/libfdisk/src/libfdisk.sym b/libfdisk/src/libfdisk.sym
index 8d38332b9..c9f35bebb 100644
--- a/libfdisk/src/libfdisk.sym
+++ b/libfdisk/src/libfdisk.sym
@@ -297,3 +297,7 @@ FDISK_2.32 {
 	fdisk_label_get_geomrange_heads;
 	fdisk_label_get_geomrange_cylinders;
 } FDISK_2.31;
+
+FDISK_2.33 {
+	fdisk_ask_number_is_wrap_negative;
+} FDISK_2.32;
diff --git a/libfdisk/src/sgi.c b/libfdisk/src/sgi.c
index 19d799205..f38e9a09c 100644
--- a/libfdisk/src/sgi.c
+++ b/libfdisk/src/sgi.c
@@ -925,6 +925,7 @@ static int sgi_add_partition(struct fdisk_context *cxt,
 		fdisk_ask_number_set_default(ask, fdisk_scround(cxt, last) - 1);/* default */
 		fdisk_ask_number_set_high(ask,    fdisk_scround(cxt, last) - 1);/* maximal */
 		fdisk_ask_number_set_base(ask,    fdisk_scround(cxt, first));
+		fdisk_ask_number_set_wrap_negative(ask, 1); /* wrap negative around high */
 
 		if (fdisk_use_cylinders(cxt))
 			fdisk_ask_number_set_unit(ask,
diff --git a/libfdisk/src/sun.c b/libfdisk/src/sun.c
index 30e6b7f1e..df91f543d 100644
--- a/libfdisk/src/sun.c
+++ b/libfdisk/src/sun.c
@@ -647,7 +647,7 @@ static int sun_add_partition(
 			return -ENOMEM;
 
 		snprintf(mesg, sizeof(mesg),
-			 _("Last %s or +%s or +size{K,M,G,T,P}"),
+			 _("Last %s or +/-%s or +/-size{K,M,G,T,P}"),
 			 fdisk_get_unit(cxt, FDISK_SINGULAR),
 			 fdisk_get_unit(cxt, FDISK_PLURAL));
 		fdisk_ask_set_query(ask, mesg);
@@ -670,6 +670,8 @@ static int sun_add_partition(
 			fdisk_ask_number_set_base(ask,    fdisk_scround(cxt, first));
 		}
 
+		fdisk_ask_number_set_wrap_negative(ask, 1); /* wrap negative around high */
+
 		if (fdisk_use_cylinders(cxt))
 			fdisk_ask_number_set_unit(ask,
 				     cxt->sector_size *