[PATCH] xargs: support -a args-file

[Denys Vlasenko]

Fixed, thanks!

On Wed, Aug 30, 2017 at 12:18 PM, Xabier Oneca  --  xOneca
<xoneca at gmail.com> wrote:
> Hello,
>
> 2017-08-29 21:06 GMT+02:00 Denys Vlasenko <vda.linux at googlemail.com>:
>> Applied, thanks.
>>
>> On Fri, Aug 25, 2017 at 10:42 PM, Johannes Schindelin
>> <johannes.schindelin at gmx.de> wrote:
>>> The GNU-specific option -a lets xargs read the arguments from a file
>>> rather than from stdin.
>>>
>>> This is particularly convenient when debugging in gdb interactively,
>>> and it might be of more general use.
>>>
>>> function                                             old     new   delta
>>> xargs_main                                           841     923     +82
>>> .rodata                                           164296  164330     +34
>>> packed_usage                                       32073 32085     +12
>>> ------------------------------------------------------------------------------
>>> (add/remove: 0/0 grow/shrink: 3/0 up/down: 128/0)             Total: 128 bytes
>>>
>>> Signed-off-by: Johannes Schindelin <johannes.schindelin at gmx.de>
>>> ---
>>>
>>>         As stated in the commit message, this was used for debugging, so I
>>>         could imagine that we'd want it to default to N...
>>>
>>>  findutils/xargs.c | 23 ++++++++++++++++++++++-
>>>  1 file changed, 22 insertions(+), 1 deletion(-)
>>>
>>> diff --git a/findutils/xargs.c b/findutils/xargs.c
>>> index 77e01ef6c..31f33c697 100644
>>> --- a/findutils/xargs.c
>>> +++ b/findutils/xargs.c
>>> @@ -64,6 +64,11 @@
>>>  //config:      bool "Enable -P N: processes to run in parallel"
>>>  //config:      default y
>>>  //config:      depends on XARGS
>>> +//config:
>>> +//config:config FEATURE_XARGS_SUPPORT_ARGS_FILE
>>> +//config:      bool "Enable --arg-file PATH: use file instead of stdin"
>>> +//config:      default y
>>> +//config:      depends on XARGS
>>>
>>>  //applet:IF_XARGS(APPLET_NOEXEC(xargs, xargs, BB_DIR_USR_BIN, BB_SUID_DROP, xargs))
>>>
>>> @@ -517,6 +522,9 @@ static int xargs_ask_confirmation(void)
>>>  //usage:       IF_FEATURE_XARGS_SUPPORT_ZERO_TERM(
>>>  //usage:     "\n       -0      Input is separated by NUL characters"
>>>  //usage:       )
>>> +//usage:       IF_FEATURE_XARGS_SUPPORT_ARGS_FILE(
>>> +//usage:     "\n       -a PATH Read args from file instead of stdin"
>>> +//usage:       )
>>>  //usage:     "\n       -t      Print the command on stderr before execution"
>>>  //usage:     "\n       -e[STR] STR stops input processing"
>>>  //usage:     "\n       -n N    Pass no more than N args to PROG"
>>> @@ -565,7 +573,8 @@ enum {
>>>         IF_FEATURE_XARGS_SUPPORT_TERMOPT(     "x") \
>>>         IF_FEATURE_XARGS_SUPPORT_ZERO_TERM(   "0") \
>>>         IF_FEATURE_XARGS_SUPPORT_REPL_STR(    "I:i::") \
>>> -       IF_FEATURE_XARGS_SUPPORT_PARALLEL(    "P:+")
>>> +       IF_FEATURE_XARGS_SUPPORT_PARALLEL(    "P:+") \
>>> +       IF_FEATURE_XARGS_SUPPORT_ARGS_FILE(   "a:")
>>>
>>>  int xargs_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
>>>  int xargs_main(int argc UNUSED_PARAM, char **argv)
>>> @@ -584,6 +593,7 @@ int xargs_main(int argc UNUSED_PARAM, char **argv)
>>>  #else
>>>  #define read_args process_stdin
>>>  #endif
>>> +       IF_FEATURE_XARGS_SUPPORT_PARALLEL(char *opt_a = NULL;)
>
> This should have been IF_FEATURE_XARGS_SUPPORT_ARGS_FILE...
>
>>>
>>>         INIT_G();
>>>
>>> @@ -592,6 +602,7 @@ int xargs_main(int argc UNUSED_PARAM, char **argv)
>>>                 &max_args, &max_chars, &G.eof_str, &G.eof_str
>>>                 IF_FEATURE_XARGS_SUPPORT_REPL_STR(, &G.repl_str, &G.repl_str)
>>>                 IF_FEATURE_XARGS_SUPPORT_PARALLEL(, &G.max_procs)
>>> +               IF_FEATURE_XARGS_SUPPORT_ARGS_FILE(, &opt_a)
>>>         );
>>>
>>>  #if ENABLE_FEATURE_XARGS_SUPPORT_PARALLEL
>>> @@ -599,6 +610,16 @@ int xargs_main(int argc UNUSED_PARAM, char **argv)
>>>                 G.max_procs = 100; /* let's not go crazy high */
>>>  #endif
>>>
>>> +#if ENABLE_FEATURE_XARGS_SUPPORT_ARGS_FILE
>>> +       if (opt_a) {
>>> +               int fd = open(opt_a, O_RDONLY);
>>> +               if (fd < 0)
>>> +                       bb_perror_msg_and_die("can't open '%s'", opt_a);
>>> +               if (dup2(fd, 0) < 0)
>>> +                       bb_perror_msg_and_die("Could not reopen stdin");
>>> +       }
>>> +#endif
>>> +
>>>         /* -E ""? You may wonder why not just omit -E?
>>>          * This is used for portability:
>>>          * old xargs was using "_" as default for -E / -e */
>>>
>>> base-commit: 14551b7036acf98f81d76674f351ce99148762c8
>>> --
>>> 2.14.1.windows.1.48.g37d08f901a6
>>>
>>> Published-As: https://github.com/dscho/busybox-w32/releases/tag/xargs-a-v1
>>> Fetch-It-Via: git fetch https://github.com/dscho/busybox-w32 xargs-a-v1
>
>
> Cheers,
>
> Xabier Oneca_,,_