git: 847d9b31df5e - stable/14 - subr_bus: introduce device_set_descf() and modify allocation logic

The branch stable/14 has been updated by christos:

URL: https://cgit.FreeBSD.org/src/commit/?id=847d9b31df5e6d9fb41a0d4827b88fb4cd21068e

commit 847d9b31df5e6d9fb41a0d4827b88fb4cd21068e
Author:     Christos Margiolis <christos@FreeBSD.org>
AuthorDate: 2024-01-16 16:49:15 +0000
Commit:     Christos Margiolis <christos@FreeBSD.org>
CommitDate: 2024-01-30 11:07:29 +0000

    subr_bus: introduce device_set_descf() and modify allocation logic
    
    device_set_descf() is a printf-like version of device_set_desc().
    
    Allocation code has been transferred from device_set_desc_internal() to
    device_set_desc_copy() and device_set_descf() to avoid complicating
    device_set_desc_internal(). The "copy" argument in
    device_set_desc_internal() has been replaced with a flag which is set
    when the description string has been allocated with M_BUS.
    
    Sponsored by:   The FreeBSD Foundation
    MFC after:      2 weeks
    Reviewed by:    imp, markj
    Differential Revision:  https://reviews.freebsd.org/D43370
    
    (cherry picked from commit 6b6914c1e21b625503a1b8d8d5cfdfbc4c6a6acd)
---
 share/man/man9/Makefile          |  1 +
 share/man/man9/device_set_desc.9 |  8 +++++++-
 sys/kern/subr_bus.c              | 43 ++++++++++++++++++++++++++--------------
 sys/sys/bus.h                    |  1 +
 4 files changed, 37 insertions(+), 16 deletions(-)

diff --git a/share/man/man9/Makefile b/share/man/man9/Makefile
index 77b2038628be..505298899561 100644
--- a/share/man/man9/Makefile
+++ b/share/man/man9/Makefile
@@ -1011,6 +1011,7 @@ MLINKS+=device_get_sysctl.9 device_get_sysctl_ctx.9 \
 MLINKS+=device_quiet.9 device_is_quiet.9 \
 	device_quiet.9 device_verbose.9
 MLINKS+=device_set_desc.9 device_get_desc.9 \
+	device_set_desc.9 device_set_descf.9 \
 	device_set_desc.9 device_set_desc_copy.9
 MLINKS+=device_set_flags.9 device_get_flags.9
 MLINKS+=devstat.9 devicestat.9 \
diff --git a/share/man/man9/device_set_desc.9 b/share/man/man9/device_set_desc.9
index 69d6cfe18c6b..5037c90fedb1 100644
--- a/share/man/man9/device_set_desc.9
+++ b/share/man/man9/device_set_desc.9
@@ -26,11 +26,12 @@
 .\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 .\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 .\"
-.Dd June 16, 1998
+.Dd January 9, 2024
 .Dt DEVICE_SET_DESC 9
 .Os
 .Sh NAME
 .Nm device_set_desc ,
+.Nm device_set_descf ,
 .Nm device_set_desc_copy ,
 .Nm device_get_desc
 .Nd access the description of a device
@@ -40,6 +41,8 @@
 .Ft void
 .Fn device_set_desc "device_t dev" "const char *desc"
 .Ft void
+.Fn device_set_descf "device_t dev" "const char *fmt" "..."
+.Ft void
 .Fn device_set_desc_copy "device_t dev" "const char *desc"
 .Ft const char *
 .Fn device_get_desc "device_t dev"
@@ -54,6 +57,9 @@ is used to set the description if the string passed is a temporary
 buffer which will be overwritten.
 In this case, the system will copy
 the string, otherwise the pointer passed will be used directly.
+.Fn device_set_descf
+is a printf-like version of
+.Fn device_set_desc .
 .Sh SEE ALSO
 .Xr device 9
 .Sh AUTHORS
diff --git a/sys/kern/subr_bus.c b/sys/kern/subr_bus.c
index 040b3556d156..d3db7ca5431c 100644
--- a/sys/kern/subr_bus.c
+++ b/sys/kern/subr_bus.c
@@ -1997,7 +1997,7 @@ device_log(device_t dev, int pri, const char * fmt, ...)
  * @internal
  */
 static void
-device_set_desc_internal(device_t dev, const char* desc, int copy)
+device_set_desc_internal(device_t dev, const char *desc, bool allocated)
 {
 	if (dev->desc && (dev->flags & DF_DESCMALLOCED)) {
 		free(dev->desc, M_BUS);
@@ -2005,16 +2005,9 @@ device_set_desc_internal(device_t dev, const char* desc, int copy)
 		dev->desc = NULL;
 	}
 
-	if (copy && desc) {
-		dev->desc = malloc(strlen(desc) + 1, M_BUS, M_NOWAIT);
-		if (dev->desc) {
-			strcpy(dev->desc, desc);
-			dev->flags |= DF_DESCMALLOCED;
-		}
-	} else {
-		/* Avoid a -Wcast-qual warning */
-		dev->desc = (char *)(uintptr_t) desc;
-	}
+	if (allocated && desc)
+		dev->flags |= DF_DESCMALLOCED;
+	dev->desc = __DECONST(char *, desc);
 
 	bus_data_generation_update();
 }
@@ -2027,9 +2020,26 @@ device_set_desc_internal(device_t dev, const char* desc, int copy)
  * call to device_set_desc() or device_set_desc_copy()).
  */
 void
-device_set_desc(device_t dev, const char* desc)
+device_set_desc(device_t dev, const char *desc)
+{
+	device_set_desc_internal(dev, desc, false);
+}
+
+/**
+ * @brief Set the device's description
+ *
+ * A printf-like version of device_set_desc().
+ */
+void
+device_set_descf(device_t dev, const char *fmt, ...)
 {
-	device_set_desc_internal(dev, desc, FALSE);
+	va_list ap;
+	char *buf = NULL;
+
+	va_start(ap, fmt);
+	vasprintf(&buf, M_BUS, fmt, ap);
+	va_end(ap);
+	device_set_desc_internal(dev, buf, true);
 }
 
 /**
@@ -2039,9 +2049,12 @@ device_set_desc(device_t dev, const char* desc)
  * the device description is generated, (e.g. with sprintf()).
  */
 void
-device_set_desc_copy(device_t dev, const char* desc)
+device_set_desc_copy(device_t dev, const char *desc)
 {
-	device_set_desc_internal(dev, desc, TRUE);
+	char *buf;
+
+	buf = strdup_flags(desc, M_BUS, M_NOWAIT);
+	device_set_desc_internal(dev, buf, true);
 }
 
 /**
diff --git a/sys/sys/bus.h b/sys/sys/bus.h
index 2ec735659452..581e81352be4 100644
--- a/sys/sys/bus.h
+++ b/sys/sys/bus.h
@@ -660,6 +660,7 @@ int	device_quiesce(device_t dev);
 void	device_quiet(device_t dev);
 void	device_quiet_children(device_t dev);
 void	device_set_desc(device_t dev, const char* desc);
+void	device_set_descf(device_t dev, const char* fmt, ...) __printflike(2, 3);
 void	device_set_desc_copy(device_t dev, const char* desc);
 int	device_set_devclass(device_t dev, const char *classname);
 int	device_set_devclass_fixed(device_t dev, const char *classname);