Re: [PATCH v2 12/12] bsd-user: Add -strict

[Philippe Mathieu-Daudé]

On 14/2/23 01:27, Warner Losh wrote:
> Most of the time, it's useful to make our best effort, but sometimes we
> want to know right away when we don't implement something. First place
> we use it is for unknown syscalls.
>
> Signed-off-by: Warner Losh <imp@bsdimp.com>
> ---
>   bsd-user/freebsd/os-syscall.c | 4 ++++
>   bsd-user/main.c               | 5 ++++-
>   bsd-user/qemu.h               | 1 +
>   3 files changed, 9 insertions(+), 1 deletion(-)
>
> diff --git a/bsd-user/freebsd/os-syscall.c b/bsd-user/freebsd/os-syscall.c
> index 179a20c304b..e2b26ecb8dd 100644
> --- a/bsd-user/freebsd/os-syscall.c
> +++ b/bsd-user/freebsd/os-syscall.c
> @@ -508,6 +508,10 @@ static abi_long freebsd_syscall(void *cpu_env, int num, 
> abi_long arg1,
>   
>       default:
>           qemu_log_mask(LOG_UNIMP, "Unsupported syscall: %d\n", num);
> +        if (bsd_user_strict) {
> +            printf("Unimplemented system call %d\n", num);
> +            abort();
> +        }
>           ret = -TARGET_ENOSYS;
>           break;
>       }
> diff --git a/bsd-user/main.c b/bsd-user/main.c
> index 41290e16f98..ba0ad86ad28 100644
> --- a/bsd-user/main.c
> +++ b/bsd-user/main.c
> @@ -91,9 +91,10 @@ unsigned long reserved_va = MAX_RESERVED_VA;
>   unsigned long reserved_va;
>   #endif
>   
> -static const char *interp_prefix = CONFIG_QEMU_INTERP_PREFIX;
> +const char *interp_prefix = CONFIG_QEMU_INTERP_PREFIX;
>   const char *qemu_uname_release;
>   char qemu_proc_pathname[PATH_MAX];  /* full path to exeutable */
> +bool bsd_user_strict = false;  /* Abort for unimplemned things */

"executable" (pre-existing), "unimplemented".

>   unsigned long target_maxtsiz = TARGET_MAXTSIZ;   /* max text size */
>   unsigned long target_dfldsiz = TARGET_DFLDSIZ;   /* initial data size limit */
> @@ -396,6 +397,8 @@ int main(int argc, char **argv)
>               trace_opt_parse(optarg);
>           } else if (!strcmp(r, "0")) {
>               argv0 = argv[optind++];
> +        } else if (!strcmp(r, "strict")) {
> +            bsd_user_strict = true;

As a debug feature, can't we just use some getenv() var?

>           } else {
>               usage();
>           }
> diff --git a/bsd-user/qemu.h b/bsd-user/qemu.h
> index e24a8cfcfb1..22bd5a3df42 100644
> --- a/bsd-user/qemu.h
> +++ b/bsd-user/qemu.h
> @@ -113,6 +113,7 @@ typedef struct TaskState {
>   
>   void stop_all_tasks(void);
>   extern const char *qemu_uname_release;
> +extern bool bsd_user_strict;
>   
>   /*
>    * TARGET_ARG_MAX defines the number of bytes allocated for arguments