git: 872065688515 - main - libusb: implement libusb_wrap_sys_device

[ShengYi Hung]

The branch main has been updated by aokblast:

URL: 
https://cgit.FreeBSD.org/src/commit/?id=872065688515c0c4549b568f7573eb9e7deeedd7

commit 872065688515c0c4549b568f7573eb9e7deeedd7
Author:     ShengYi Hung <aokbl...@freebsd.org>
AuthorDate: 2025-08-05 12:59:06 +0000
Commit:     ShengYi Hung <aokbl...@freebsd.org>
CommitDate: 2025-08-06 14:05:40 +0000

    libusb: implement libusb_wrap_sys_device
    
    The libusb_wrap_sys_device function can wrap an opened fd from the
    system into a libusb handler. However, in FreeBSD's libusb implementation, a
    USB device contains two fds: one for control transfers and another for
    normal (bulk, interrupt, isochronous) transfers.
    
    This design makes it impossible for FreeBSD to implement this function
    without exposing a different structure in libusb.h to provide two fds.
    Therefore, we return LIBUSB_ERROR_NOT_SUPPORTED to maintain API
    compatibility.
    
    Approved by:    makrj (mentor), lwhsu (mentor)
    Sponsored by:   The FreeBSD Foundation
    Differential Revision: https://reviews.freebsd.org/D51739
---
 lib/libusb/libusb.3   | 8 ++++++++
 lib/libusb/libusb.h   | 1 +
 lib/libusb/libusb10.c | 7 +++++++
 3 files changed, 16 insertions(+)

diff --git a/lib/libusb/libusb.3 b/lib/libusb/libusb.3
index 3093737c05d7..09140c914d68 100644
--- a/lib/libusb/libusb.3
+++ b/lib/libusb/libusb.3
@@ -209,6 +209,14 @@ Decrement the reference counter of the device
 .Fa dev .
 .Pp
 .Ft int
+.Fn libusb_wrap_sys_device "libusb_context *ctx" "intptr_t sys_dev" 
"libusb_device_handle **dev_handle"
+This function creates a libusb handler from a previously opened fd
+.Fa sys_dev .
+This function is provided for compatibility and is currently unimplemented.
+It always returns
+.Dv LIBUSB_ERROR_NOT_SUPPORTED .
+.Pp
+.Ft int
 .Fn libusb_open "libusb_device *dev" "libusb_device_handle **devh"
 Open a device and obtain a device_handle.
 Returns 0 on success,
diff --git a/lib/libusb/libusb.h b/lib/libusb/libusb.h
index d8a3e4b62995..277b551c46a1 100644
--- a/lib/libusb/libusb.h
+++ b/lib/libusb/libusb.h
@@ -506,6 +506,7 @@ int libusb_get_max_packet_size(libusb_device * dev, uint8_t 
endpoint);
 int    libusb_get_max_iso_packet_size(libusb_device * dev, uint8_t endpoint);
 libusb_device *libusb_ref_device(libusb_device * dev);
 void   libusb_unref_device(libusb_device * dev);
+int    libusb_wrap_sys_device(libusb_context *ctx, intptr_t sys_dev, 
libusb_device_handle **dev_handle);
 int    libusb_open(libusb_device * dev, libusb_device_handle ** devh);
 libusb_device_handle *libusb_open_device_with_vid_pid(libusb_context * ctx, 
uint16_t vendor_id, uint16_t product_id);
 void   libusb_close(libusb_device_handle * devh);
diff --git a/lib/libusb/libusb10.c b/lib/libusb/libusb10.c
index 5c116b39ea17..e226def0b7b6 100644
--- a/lib/libusb/libusb10.c
+++ b/lib/libusb/libusb10.c
@@ -1918,3 +1918,10 @@ libusb_dev_mem_free(libusb_device_handle *devh, unsigned 
char *buffer,
 {
        return (LIBUSB_ERROR_NOT_SUPPORTED);
 }
+
+int
+libusb_wrap_sys_device(libusb_context *ctx, intptr_t sys_dev,
+    libusb_device_handle **dev_handle)
+{
+       return (LIBUSB_ERROR_NOT_SUPPORTED);
+}