Re: [PATCH 09/16] src: Use eu-search in nm and findtextrel.

[Mark Wielaard <mark@klomp.org>]

Hi Heather,

On Tue, Oct 10, 2023 at 03:42:53PM +0200, Mark Wielaard wrote:
> From: Heather McIntyre <hsm2@rice.edu>
> 
> 	* src/Makefile.am: Add USE_LOCKS condition for -pthread.
> 	* src/findtextrel.c: Add eu-search.h and remove search.h.
> 	Change calls of tsearch/tfind to eu_tsearch/eu_tfind.
> 	* src/nm.c: Likewise.

This does look technically correct. But both nm and findtextrel are
single threaded programs. It might be interesting to try to make them
parallel. But currently I think this would just introduce unnecessary
locking.

Cheers,

Mark

> Signed-off-by: Heather S. McIntyre <hsm2@rice.edu>
> Signed-off-by: Mark Wielaard <mark@klomp.org>
> ---
>  src/Makefile.am   |  3 +++
>  src/findtextrel.c | 10 +++++-----
>  src/nm.c          | 10 +++++-----
>  3 files changed, 13 insertions(+), 10 deletions(-)
> 
> diff --git a/src/Makefile.am b/src/Makefile.am
> index 10d59a48..fea5d43e 100644
> --- a/src/Makefile.am
> +++ b/src/Makefile.am
> @@ -22,6 +22,9 @@ DEFS += $(YYDEBUG) -DDEBUGPRED=@DEBUGPRED@ \
>  AM_CPPFLAGS += -I$(srcdir)/../libelf -I$(srcdir)/../libebl \
>  	    -I$(srcdir)/../libdw -I$(srcdir)/../libdwelf \
>  	    -I$(srcdir)/../libdwfl -I$(srcdir)/../libasm
> +if USE_LOCKS
> +  AM_CFLAGS += -pthread
> +endif
>  
>  AM_LDFLAGS = -Wl,-rpath-link,../libelf:../libdw $(STACK_USAGE_NO_ERROR)
>  
> diff --git a/src/findtextrel.c b/src/findtextrel.c
> index d3021a3a..5ac4c29a 100644
> --- a/src/findtextrel.c
> +++ b/src/findtextrel.c
> @@ -27,7 +27,7 @@
>  #include <gelf.h>
>  #include <libdw.h>
>  #include <locale.h>
> -#include <search.h>
> +#include <eu-search.h>
>  #include <stdbool.h>
>  #include <stdio.h>
>  #include <stdlib.h>
> @@ -501,10 +501,10 @@ check_rel (size_t nsegments, struct segments segments[nsegments],
>  	    /* There can be more than one relocation against one file.
>  	       Try to avoid multiple messages.  And yes, the code uses
>  	       pointer comparison.  */
> -	    if (tfind (src, knownsrcs, ptrcompare) == NULL)
> +	    if (eu_tfind (src, knownsrcs, ptrcompare) == NULL)
>  	      {
>  		printf (_("%s not compiled with -fpic/-fPIC\n"), src);
> -		tsearch (src, knownsrcs, ptrcompare);
> +		eu_tsearch (src, knownsrcs, ptrcompare);
>  	      }
>  	    return;
>  	  }
> @@ -555,12 +555,12 @@ check_rel (size_t nsegments, struct segments segments[nsegments],
>  		    if (sym->st_value + sym->st_size > addr)
>  		      {
>  			/* It is this function.  */
> -			if (tfind (lowstr, knownsrcs, ptrcompare) == NULL)
> +			if (eu_tfind (lowstr, knownsrcs, ptrcompare) == NULL)
>  			  {
>  			    printf (_("\
>  the file containing the function '%s' is not compiled with -fpic/-fPIC\n"),
>  				    lowstr);
> -			    tsearch (lowstr, knownsrcs, ptrcompare);
> +			    eu_tsearch (lowstr, knownsrcs, ptrcompare);
>  			  }
>  		      }
>  		    else if (highidx == -1)
> diff --git a/src/nm.c b/src/nm.c
> index fbdee8e1..44c20fb2 100644
> --- a/src/nm.c
> +++ b/src/nm.c
> @@ -32,7 +32,7 @@
>  #include <libdw.h>
>  #include <locale.h>
>  #include <obstack.h>
> -#include <search.h>
> +#include <eu-search.h>
>  #include <stdbool.h>
>  #include <stdio.h>
>  #include <stdio_ext.h>
> @@ -537,7 +537,7 @@ static int
>  get_global (Dwarf *dbg __attribute__ ((unused)), Dwarf_Global *global,
>  	    void *arg __attribute__ ((unused)))
>  {
> -  tsearch (memcpy (xmalloc (sizeof (Dwarf_Global)), global,
> +  eu_tsearch (memcpy (xmalloc (sizeof (Dwarf_Global)), global,
>  		   sizeof (Dwarf_Global)),
>  	   &global_root, global_compare);
>  
> @@ -696,7 +696,7 @@ get_local_names (Dwarf *dbg)
>  	   /* Check whether a similar local_name is already in the
>  	      cache.  That should not happen.  But if it does, we
>  	      don't want to leak memory.  */
> -	    struct local_name **tres = tsearch (newp, &local_root,
> +	    struct local_name **tres = eu_tsearch (newp, &local_root,
>  						local_compare);
>  	    if (tres == NULL)
>                error_exit (errno, _("cannot create search tree"));
> @@ -1387,7 +1387,7 @@ show_symbols (int fd, Ebl *ebl, GElf_Ehdr *ehdr,
>  	      && global_root != NULL)
>  	    {
>  	      Dwarf_Global fake = { .name = symstr };
> -	      Dwarf_Global **found = tfind (&fake, &global_root,
> +	      Dwarf_Global **found = eu_tfind (&fake, &global_root,
>  					    global_compare);
>  	      if (found != NULL)
>  		{
> @@ -1442,7 +1442,7 @@ show_symbols (int fd, Ebl *ebl, GElf_Ehdr *ehdr,
>  		  .lowpc = sym->st_value,
>  		  .highpc = sym->st_value,
>  		};
> -	      struct local_name **found = tfind (&fake, &local_root,
> +	      struct local_name **found = eu_tfind (&fake, &local_root,
>  						 local_compare);
>  	      if (found != NULL)
>  		{
> -- 
> 2.41.0
>