Re: git: f84a0da4e060 - main - libusb: rename bNumDeviceCapabilities to bNumDeviceCaps for compatibility with libusb

hi! Thanks for this!

Could we possibly wrap stuff like these compat macros in a #define that we
can undefine? So we can make sure no new code shows up that uses the "old"
paths?

eg LIBUSB10_NO_BACKWARDS_COMPAT / LIBUSB20_NO_BACKWARDS_COMPAT ?

Thanks!



-adrian


On Tue, 8 Jul 2025 at 08:12, ShengYi Hung <aokblast@freebsd.org> wrote:

> The branch main has been updated by aokblast:
>
> URL:
> https://cgit.FreeBSD.org/src/commit/?id=f84a0da4e0608a970c775f3d605f8de2b0b8d322
>
> commit f84a0da4e0608a970c775f3d605f8de2b0b8d322
> Author:     ShengYi Hung <aokblast@FreeBSD.org>
> AuthorDate: 2025-06-07 19:43:15 +0000
> Commit:     ShengYi Hung <aokblast@FreeBSD.org>
> CommitDate: 2025-07-08 15:11:41 +0000
>
>     libusb: rename bNumDeviceCapabilities to bNumDeviceCaps for
> compatibility with libusb
>
>     THe member bNumDeviceCapabilities is referred to as bNumDeviceCaps in
>     the upstream libusb project.
>
>     To improve compatibility, we are renaming the member accordingly.
>
>     For backward compatibility, a mocro will be defined to map
>     bNumDeviceCapabilities to bNumDeviceCaps.
>
>     See:
> https://github.com/libusb/libusb/commit/02ebafc85d3f219842cbabaf78abc8100b6656e5
>
>     Reviewed by:    kevans
>     Approved by:    markj (mentor)
>     MFC after:      2 weeks
>     Sponsored by:   FreeBSD Foundation
>     Differential Revision: https://reviews.freebsd.org/D50740
> ---
>  lib/libusb/libusb.h        |  5 ++++-
>  lib/libusb/libusb10_desc.c | 11 ++++++-----
>  lib/libusb/libusb20_desc.h |  6 +++++-
>  3 files changed, 15 insertions(+), 7 deletions(-)
>
> diff --git a/lib/libusb/libusb.h b/lib/libusb/libusb.h
> index 0aad29aa4ecc..491af3d0a5ec 100644
> --- a/lib/libusb/libusb.h
> +++ b/lib/libusb/libusb.h
> @@ -418,7 +418,10 @@ typedef struct libusb_bos_descriptor {
>         uint8_t bLength;
>         uint8_t bDescriptorType;
>         uint16_t wTotalLength;
> -       uint8_t bNumDeviceCapabilities;
> +#ifndef bNumDeviceCapabilities
> +#define bNumDeviceCapabilities bNumDeviceCaps
> +#endif
> +       uint8_t bNumDeviceCaps;
>         struct libusb_usb_2_0_device_capability_descriptor
> *usb_2_0_ext_cap;
>         struct libusb_ss_usb_device_capability_descriptor *ss_usb_cap;
>         struct libusb_bos_dev_capability_descriptor **dev_capability;
> diff --git a/lib/libusb/libusb10_desc.c b/lib/libusb/libusb10_desc.c
> index 3e36009cbb3a..5f4c46740688 100644
> --- a/lib/libusb/libusb10_desc.c
> +++ b/lib/libusb/libusb10_desc.c
> @@ -470,10 +470,11 @@ libusb_parse_bos_descriptor(const void *buf, int len,
>                         ptr->bDescriptorType = dtype;
>                         ptr->wTotalLength = ((const uint8_t *)buf)[2] |
>                             (((const uint8_t *)buf)[3] << 8);
> -                       ptr->bNumDeviceCapabilities = ((const uint8_t
> *)buf)[4];
> +                       ptr->bNumDeviceCaps = ((const uint8_t *)buf)[4];
>                         ptr->usb_2_0_ext_cap = NULL;
>                         ptr->ss_usb_cap = NULL;
> -                       ptr->dev_capability =
> calloc(ptr->bNumDeviceCapabilities, sizeof(void *));
> +                       ptr->dev_capability = calloc(ptr->bNumDeviceCaps,
> +                           sizeof(void *));
>                         if (ptr->dev_capability == NULL) {
>                                 free(ptr);
>                                 return (LIBUSB_ERROR_NO_MEM);
> @@ -485,7 +486,7 @@ libusb_parse_bos_descriptor(const void *buf, int len,
>                 if (dlen >= 3 &&
>                     ptr != NULL &&
>                     dtype == LIBUSB_DT_DEVICE_CAPABILITY) {
> -                       if (index != ptr->bNumDeviceCapabilities) {
> +                       if (index != ptr->bNumDeviceCaps) {
>                                 ptr->dev_capability[index] = malloc(dlen);
>                                 if (ptr->dev_capability[index] == NULL) {
>                                         libusb_free_bos_descriptor(ptr);
> @@ -542,7 +543,7 @@ libusb_parse_bos_descriptor(const void *buf, int len,
>         }
>
>         if (ptr != NULL) {
> -               ptr->bNumDeviceCapabilities = index;
> +               ptr->bNumDeviceCaps = index;
>                 return (0);             /* success */
>         }
>
> @@ -557,7 +558,7 @@ libusb_free_bos_descriptor(struct
> libusb_bos_descriptor *bos)
>         if (bos == NULL)
>                 return;
>
> -       for (i = 0; i != bos->bNumDeviceCapabilities; i++)
> +       for (i = 0; i != bos->bNumDeviceCaps; i++)
>                 free(bos->dev_capability[i]);
>         free(bos->dev_capability);
>         free(bos);
> diff --git a/lib/libusb/libusb20_desc.h b/lib/libusb/libusb20_desc.h
> index 017148a34b1c..0f7c9294ebc8 100644
> --- a/lib/libusb/libusb20_desc.h
> +++ b/lib/libusb/libusb20_desc.h
> @@ -298,11 +298,15 @@ LIBUSB20_MAKE_STRUCT(LIBUSB20_USB_20_DEVCAP_DESC);
>
>  LIBUSB20_MAKE_STRUCT(LIBUSB20_SS_USB_DEVCAP_DESC);
>
> +#ifndef bNumDeviceCapabilities
> +#define bNumDeviceCapabilities bNumDeviceCaps
> +#endif
> +
>  #define        LIBUSB20_BOS_DESCRIPTOR(m,n) \
>    m(n, UINT8_T,  bLength, ) \
>    m(n, UINT8_T,  bDescriptorType, ) \
>    m(n, UINT16_T, wTotalLength, ) \
> -  m(n, UINT8_T,  bNumDeviceCapabilities, ) \
> +  m(n, UINT8_T,  bNumDeviceCaps, ) \
>
>  LIBUSB20_MAKE_STRUCT(LIBUSB20_BOS_DESCRIPTOR);
>
>