[08/28] elf: Implement ld.so --version

  This prints out version information for the dynamic loader and
exits immediately, without further command line processing
(which seems to match what some GNU tools do).
---
 elf/dl-main.h  |  3 +++
 elf/dl-usage.c | 15 +++++++++++++++
 elf/rtld.c     |  2 ++
 3 files changed, 20 insertions(+)
  

On 01/10/2020 13:32, Florian Weimer via Libc-alpha wrote:
> This prints out version information for the dynamic loader and
> exits immediately, without further command line processing
> (which seems to match what some GNU tools do).

Some comments below.

> ---
>  elf/dl-main.h  |  3 +++
>  elf/dl-usage.c | 15 +++++++++++++++
>  elf/rtld.c     |  2 ++
>  3 files changed, 20 insertions(+)
> 
> diff --git a/elf/dl-main.h b/elf/dl-main.h
> index 71ca5114de..0df849d3cd 100644
> --- a/elf/dl-main.h
> +++ b/elf/dl-main.h
> @@ -101,6 +101,9 @@ call_init_paths (const struct dl_main_state *state)
>  void _dl_usage (const char *argv0, const char *wrong_option)
>    attribute_hidden __attribute__ ((__noreturn__));
>  
> +/* Print ld.so version information and exit.  */
> +void _dl_version (void) attribute_hidden __attribute__ ((__noreturn__));
> +

Maybe _Noreturn here?

>  /* Print ld.so --help output and exit.  */
>  void _dl_help (const char *argv0, struct dl_main_state *state)
>    attribute_hidden __attribute__ ((__noreturn__));
> diff --git a/elf/dl-usage.c b/elf/dl-usage.c
> index 72ff99e70f..7355b094a5 100644
> --- a/elf/dl-usage.c
> +++ b/elf/dl-usage.c
> @@ -20,6 +20,7 @@
>  #include <dl-main.h>
>  #include <ldsodefs.h>
>  #include <unistd.h>
> +#include "version.h"
>  
>  void
>  _dl_usage (const char *argv0, const char *wrong_option)
> @@ -32,6 +33,19 @@ _dl_usage (const char *argv0, const char *wrong_option)
>    _exit (1);
>  }
>  
> +void
> +_dl_version (void)
> +{
> +  _dl_printf ("\
> +ld.so " PKGVERSION RELEASE " release version " VERSION ".\n\
> +Copyright (C) 2020 Free Software Foundation, Inc.\n\
> +This is free software; see the source for copying conditions.\n\
> +There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A\n\
> +PARTICULAR PURPOSE.\n\
> +");
> +  _exit (0);
> +}
> +

I think we will need a way to embedded the Copyright year using a macro
to avoid need to manually update it on each year.

>  void
>  _dl_help (const char *argv0, struct dl_main_state *state)
>  {
> @@ -61,6 +75,7 @@ of this helper program; chances are you did not intend to run this program.\n\
>    --preload LIST        preload objects named in LIST\n\
>    --argv0 STRING        set argv[0] to STRING before running\n\
>    --help                display this help and exit\n\
> +  --version             output version information and exit\n\
>  ",
>                argv0);
>    _exit (0);
> diff --git a/elf/rtld.c b/elf/rtld.c
> index 5cdab3c99c..e0e8e98c2f 100644
> --- a/elf/rtld.c
> +++ b/elf/rtld.c
> @@ -1254,6 +1254,8 @@ dl_main (const ElfW(Phdr) *phdr,
>  	    --_dl_argc;
>  	    ++_dl_argv;
>  	  }
> +	else if (strcmp (_dl_argv[1], "--version") == 0)
> +	  _dl_version ();
>  	else if (_dl_argv[1][0] == '-' && _dl_argv[1][1] == '-')
>  	  {
>  	   if (_dl_argv[1][1] == '\0')
> 

Ok.
  

On 07/10/2020 15:36, Adhemerval Zanella wrote:
> 
> 
> On 01/10/2020 13:32, Florian Weimer via Libc-alpha wrote:
>> This prints out version information for the dynamic loader and
>> exits immediately, without further command line processing
>> (which seems to match what some GNU tools do).
> 
> Some comments below.
> 
>> ---
>>  elf/dl-main.h  |  3 +++
>>  elf/dl-usage.c | 15 +++++++++++++++
>>  elf/rtld.c     |  2 ++
>>  3 files changed, 20 insertions(+)
>>
>> diff --git a/elf/dl-main.h b/elf/dl-main.h
>> index 71ca5114de..0df849d3cd 100644
>> --- a/elf/dl-main.h
>> +++ b/elf/dl-main.h
>> @@ -101,6 +101,9 @@ call_init_paths (const struct dl_main_state *state)
>>  void _dl_usage (const char *argv0, const char *wrong_option)
>>    attribute_hidden __attribute__ ((__noreturn__));
>>  
>> +/* Print ld.so version information and exit.  */
>> +void _dl_version (void) attribute_hidden __attribute__ ((__noreturn__));
>> +
> 
> Maybe _Noreturn here?
> 
>>  /* Print ld.so --help output and exit.  */
>>  void _dl_help (const char *argv0, struct dl_main_state *state)
>>    attribute_hidden __attribute__ ((__noreturn__));
>> diff --git a/elf/dl-usage.c b/elf/dl-usage.c
>> index 72ff99e70f..7355b094a5 100644
>> --- a/elf/dl-usage.c
>> +++ b/elf/dl-usage.c
>> @@ -20,6 +20,7 @@
>>  #include <dl-main.h>
>>  #include <ldsodefs.h>
>>  #include <unistd.h>
>> +#include "version.h"
>>  
>>  void
>>  _dl_usage (const char *argv0, const char *wrong_option)
>> @@ -32,6 +33,19 @@ _dl_usage (const char *argv0, const char *wrong_option)
>>    _exit (1);
>>  }
>>  
>> +void
>> +_dl_version (void)
>> +{
>> +  _dl_printf ("\
>> +ld.so " PKGVERSION RELEASE " release version " VERSION ".\n\
>> +Copyright (C) 2020 Free Software Foundation, Inc.\n\
>> +This is free software; see the source for copying conditions.\n\
>> +There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A\n\
>> +PARTICULAR PURPOSE.\n\
>> +");
>> +  _exit (0);
>> +}
>> +
> 
> I think we will need a way to embedded the Copyright year using a macro
> to avoid need to manually update it on each year.

And I just noted you are handling on the scripts/update-copyrights,
so this should be ok.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>

> 
>>  void
>>  _dl_help (const char *argv0, struct dl_main_state *state)
>>  {
>> @@ -61,6 +75,7 @@ of this helper program; chances are you did not intend to run this program.\n\
>>    --preload LIST        preload objects named in LIST\n\
>>    --argv0 STRING        set argv[0] to STRING before running\n\
>>    --help                display this help and exit\n\
>> +  --version             output version information and exit\n\
>>  ",
>>                argv0);
>>    _exit (0);
>> diff --git a/elf/rtld.c b/elf/rtld.c
>> index 5cdab3c99c..e0e8e98c2f 100644
>> --- a/elf/rtld.c
>> +++ b/elf/rtld.c
>> @@ -1254,6 +1254,8 @@ dl_main (const ElfW(Phdr) *phdr,
>>  	    --_dl_argc;
>>  	    ++_dl_argv;
>>  	  }
>> +	else if (strcmp (_dl_argv[1], "--version") == 0)
>> +	  _dl_version ();
>>  	else if (_dl_argv[1][0] == '-' && _dl_argv[1][1] == '-')
>>  	  {
>>  	   if (_dl_argv[1][1] == '\0')
>>
> 
> Ok.
>
  

* Adhemerval Zanella via Libc-alpha:

> Maybe _Noreturn here?

Fixed.

>> +void
>> +_dl_version (void)
>> +{
>> +  _dl_printf ("\
>> +ld.so " PKGVERSION RELEASE " release version " VERSION ".\n\
>> +Copyright (C) 2020 Free Software Foundation, Inc.\n\
>> +This is free software; see the source for copying conditions.\n\
>> +There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A\n\
>> +PARTICULAR PURPOSE.\n\
>> +");
>> +  _exit (0);
>> +}

Also switched to EXIT_SUCCESS here.

Pushed with these changes based on your later comment:

> And I just noted you are handling on the scripts/update-copyrights,
> so this should be ok.
> 
> Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>

Thanks,
Florian