Re: [PATCH] linux-user: Add strace for prlimit64() syscall

[Laurent Vivier <laurent@vivier.eu>]

Le 22/12/2022 à 20:06, Helge Deller a écrit :
> Add proper prlimit64() strace output.
> 
> Signed-off-by: Helge Deller <deller@gmx.de>
> ---
>   linux-user/strace.c    | 89 ++++++++++++++++++++++++++++++++++++++++++
>   linux-user/strace.list |  3 +-
>   2 files changed, 91 insertions(+), 1 deletion(-)
> 
> diff --git a/linux-user/strace.c b/linux-user/strace.c
> index 3ea91084fb..82dc1a1e20 100644
> --- a/linux-user/strace.c
> +++ b/linux-user/strace.c
> @@ -3774,6 +3774,95 @@ print_futex(CPUArchState *cpu_env, const struct syscallname *name,
>   }
>   #endif
> 
> +#ifdef TARGET_NR_prlimit64
> +static const char *target_ressource_string(abi_ulong r)
> +{
> +    #define RET_RES_ENTRY(res) case TARGET_##res:  return #res;
> +    switch (r) {
> +    RET_RES_ENTRY(RLIMIT_AS);
> +    RET_RES_ENTRY(RLIMIT_CORE);
> +    RET_RES_ENTRY(RLIMIT_CPU);
> +    RET_RES_ENTRY(RLIMIT_DATA);
> +    RET_RES_ENTRY(RLIMIT_FSIZE);
> +    RET_RES_ENTRY(RLIMIT_LOCKS);
> +    RET_RES_ENTRY(RLIMIT_MEMLOCK);
> +    RET_RES_ENTRY(RLIMIT_MSGQUEUE);
> +    RET_RES_ENTRY(RLIMIT_NICE);
> +    RET_RES_ENTRY(RLIMIT_NOFILE);
> +    RET_RES_ENTRY(RLIMIT_NPROC);
> +    RET_RES_ENTRY(RLIMIT_RSS);
> +    RET_RES_ENTRY(RLIMIT_RTPRIO);
> +#ifdef RLIMIT_RTTIME
> +    RET_RES_ENTRY(RLIMIT_RTTIME);
> +#endif
> +    RET_RES_ENTRY(RLIMIT_SIGPENDING);
> +    RET_RES_ENTRY(RLIMIT_STACK);
> +    default:
> +        return NULL;
> +    }
> +    #undef RET_RES_ENTRY
> +}
> +
> +static void
> +print_rlimit64(abi_ulong rlim_addr, int last)
> +{
> +    if (rlim_addr) {
> +        struct target_rlimit64 *rl;
> +
> +        rl = lock_user(VERIFY_READ, rlim_addr, sizeof(*rl), 1);
> +        if (!rl) {
> +            print_pointer(rlim_addr, last);
> +            return;
> +        }
> +        qemu_log("{rlim_cur = %lld, rlim_max = %lld}%s",
> +                 (long long)tswap64(rl->rlim_cur),
> +                 (long long)tswap64(rl->rlim_max),
> +                 get_comma(last));
> +        unlock_user(rl, rlim_addr, 0);
> +    } else {
> +        qemu_log("NULL%s", get_comma(last));
> +    }
> +}
> +
> +static void
> +print_prlimit64(CPUArchState *cpu_env, const struct syscallname *name,
> +           abi_long arg0, abi_long arg1, abi_long arg2,
> +           abi_long arg3, abi_long arg4, abi_long arg5)
> +{
> +    const char *rlim_name;
> +
> +    print_syscall_prologue(name);
> +    print_raw_param("%d", arg0, 0);
> +    rlim_name = target_ressource_string(arg1);
> +    if (rlim_name) {
> +        qemu_log("%s,", rlim_name);
> +    } else {
> +        print_raw_param("%d", arg1, 0);
> +    }
> +    print_rlimit64(arg2, 0);
> +    print_pointer(arg3, 1);
> +    print_syscall_epilogue(name);
> +}
> +
> +static void
> +print_syscall_ret_prlimit64(CPUArchState *cpu_env,
> +                       const struct syscallname *name,
> +                       abi_long ret, abi_long arg0, abi_long arg1,
> +                       abi_long arg2, abi_long arg3, abi_long arg4,
> +                       abi_long arg5)
> +{
> +    if (!print_syscall_err(ret)) {
> +        qemu_log(TARGET_ABI_FMT_ld, ret);
> +        if (arg3) {
> +            qemu_log(" (");
> +            print_rlimit64(arg3, 1);
> +            qemu_log(")");
> +        }
> +    }
> +    qemu_log("\n");
> +}
> +#endif
> +
>   #ifdef TARGET_NR_kill
>   static void
>   print_kill(CPUArchState *cpu_env, const struct syscallname *name,
> diff --git a/linux-user/strace.list b/linux-user/strace.list
> index ac8f872371..f9254725a1 100644
> --- a/linux-user/strace.list
> +++ b/linux-user/strace.list
> @@ -1067,7 +1067,8 @@
>   { TARGET_NR_preadv, "preadv" , NULL, NULL, NULL },
>   #endif
>   #ifdef TARGET_NR_prlimit64
> -{ TARGET_NR_prlimit64, "prlimit64" , NULL, NULL, NULL },
> +{ TARGET_NR_prlimit64, "prlimit64" , NULL, print_prlimit64,
> +                    print_syscall_ret_prlimit64 },
>   #endif
>   #ifdef TARGET_NR_process_vm_readv
>   { TARGET_NR_process_vm_readv, "process_vm_readv" , NULL, NULL, NULL },
> --
> 2.38.1
> 
> 

Applied to my linux-user-for-8.0 branch.

Thanks,
Laurent