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

[Heather McIntyre]

Thank you for pointing out that changes to these two files are not needed
due to them being single threaded utilities. I reverted the changes and ran
some tests. Works just fine with the original search.h, tsearch, and tfind.

On Tue, Oct 10, 2023 at 4:26 PM Mark Wielaard <mark@klomp.org> wrote:

> 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
> >
>
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