[PATCH v1] erofs-utils: lib: oci: support auto-detecting host platform

[Gao Xiang]

Hi Chengyu,

On 2026/1/10 16:27, ChengyuZhu6 wrote:
> From: Chengyu Zhu <hudsonzhu at tencent.com>
> 
> Currently, the platform is hard-coded to "linux/amd64" if not specified.
> This patch introduces `ocierofs_get_platform_spec` helper to detect the
> host platform (OS and architecture) at compile time.
> 
> Signed-off-by: Chengyu Zhu <hudsonzhu at tencent.com>
> ---
>   lib/remotes/oci.c | 46 ++++++++++++++++++++++++++++++++++++++++++++--
>   1 file changed, 44 insertions(+), 2 deletions(-)
> 
> diff --git a/lib/remotes/oci.c b/lib/remotes/oci.c
> index c8711ea..911abd5 100644
> --- a/lib/remotes/oci.c
> +++ b/lib/remotes/oci.c
> @@ -1089,13 +1089,55 @@ static int ocierofs_parse_ref(struct ocierofs_ctx *ctx, const char *ref_str)
>   	return 0;
>   }
>   
> +static char *ocierofs_get_platform_spec(void)
> +{
> +#if defined(__linux__)
> +	const char *os = "linux";
> +#elif defined(__APPLE__)
> +	const char *os = "darwin";
> +#elif defined(_WIN32)
> +	const char *os = "windows";
> +#elif defined(__FreeBSD__)
> +	const char *os = "freebsd";
> +#else

Is there an unknown os annotation or we should just error out?

> +	const char *os = "linux";
> +#endif

I think it would be better to rearrange it as:
	const char *os, *platform;


#if defined(__linux__)
	os = "linux";
#elif defined(__APPLE__)
	os = "darwin"
#elif ...
#else
	return -EOPNOTSUPP;
#endif

> +
> +#if defined(__x86_64__) || defined(__amd64__)
> +	const char *arch = "amd64";
> +#elif defined(__aarch64__) || defined(__arm64__)
> +	const char *arch = "arm64";
> +#elif defined(__i386__)
> +	const char *arch = "386";
> +#elif defined(__arm__)
> +	const char *arch = "arm";
> +#elif defined(__riscv) && (__riscv_xlen == 64)
> +	const char *arch = "riscv64";
> +#elif defined(__ppc64__)
> +#if defined(__BYTE_ORDER__) && (__BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__)
> +	const char *arch = "ppc64le";
> +#else
> +	const char *arch = "ppc64";
> +#endif
> +#elif defined(__s390x__)
> +	const char *arch = "s390x";
> +#else
> +	const char *arch = "amd64";

Same here and
Is there an unknown platform annotation or we should just error out?

Thanks,
Gao Xiang