[committed] Factor out dwz_files_1

[Tom de Vries <tdevries@suse.de>]

Hi,

In dwz_files, a variable resa is malloced at the start, and freed at the end.
This prevents (early) returns, which makes the code more complicated than
necessary.  Also, the function already contains an early return, which means
it leaks resa.

Fix this by factoring out dwz_files_1 out of dwz_files, where dwz_files is a
wrapper tasked with alloc/free of variable resa.

Committed to trunk.

Thanks,
- Tom

Factor out dwz_files_1

2021-03-23  Tom de Vries  <tdevries@suse.de>

	* dwz.c (dwz_files_1): New function, factored out of ...
	(dwz_files): ... here.

---
 dwz.c | 111 +++++++++++++++++++++++++++++++++++++-----------------------------
 1 file changed, 62 insertions(+), 49 deletions(-)

diff --git a/dwz.c b/dwz.c
index a7aa23b..4fc01a3 100644
--- a/dwz.c
+++ b/dwz.c
@@ -16285,18 +16285,15 @@ dwz_one_file (const char *file, const char *outfile)
 /* Dwarf-compress FILES.  If HARDLINK, detect if some files are hardlinks and
    if so, dwarf-compress just one, and relink the others.  */
 static int
-dwz_files (int nr_files, char *files[], bool hardlink)
+dwz_files_1 (int nr_files, char *files[], bool hardlink,
+	     struct file_result *resa)
 {
   int ret = 0;
   int i;
   const char *file;
-  struct file_result *resa;
   bool hardlinks = false;
   int successcount = 0;
 
-  resa = (struct file_result *) malloc ((nr_files) * sizeof (*resa));
-  if (resa == NULL)
-    error (1, ENOMEM, "failed to allocate result array");
   for (i = 0; i < nr_files; ++i)
     resa[i].die_count = 0;
 
@@ -16344,65 +16341,81 @@ dwz_files (int nr_files, char *files[], bool hardlink)
 	hardlinks = true;
     }
 
-  if (multifile && successcount < 2)
+  if (multifile == NULL)
+    return ret;
+
+  if (successcount < 2)
     {
       error (0, 0, "Too few files for multifile optimization");
-      multifile = NULL;
+      return ret;
     }
 
-  if (multifile
-      && multi_info_off == 0 && multi_str_off == 0 && multi_macro_off == 0)
+  if (multi_info_off == 0 && multi_str_off == 0 && multi_macro_off == 0)
     {
       if (!quiet)
 	error (0, 0, "No suitable DWARF found for multifile optimization");
-      multifile = NULL;
+      return ret;
     }
 
-  if (multifile)
+  unsigned int multifile_die_count = 0;
+  int multi_fd = optimize_multifile (&multifile_die_count);
+  DSO *dso;
+  if (multi_fd == -1)
+    return 1;
+
+  dso = read_multifile (multi_fd, multifile_die_count);
+  if (dso == NULL)
+    ret = 1;
+  else
     {
-      unsigned int multifile_die_count = 0;
-      int multi_fd = optimize_multifile (&multifile_die_count);
-      DSO *dso;
-      if (multi_fd == -1)
-	return 1;
-      dso = read_multifile (multi_fd, multifile_die_count);
-      if (dso == NULL)
-	ret = 1;
-      else
+      for (i = 0; i < nr_files; i++)
 	{
-	  for (i = 0; i < nr_files; i++)
-	    {
-	      dw_cu_ref cu;
-	      file = files[i];
-	      if (stats_p)
-		init_stats (file);
-	      multifile_mode = MULTIFILE_MODE_FI;
-	      /* Don't process again files that couldn't
-		 be processed successfully.  */
-	      if (resa[i].res == -1)
-		continue;
-	      for (cu = alt_first_cu; cu; cu = cu->cu_next)
-		alt_clear_dups (cu->cu_die);
-	      ret |= dwz (file, NULL, &resa[i],
-			  hardlinks ? resa : NULL, files);
-	    }
-	  elf_end (dso->elf);
-	  close (multi_fd);
-	  free (dso);
+	  dw_cu_ref cu;
+	  file = files[i];
+	  if (stats_p)
+	    init_stats (file);
+	  multifile_mode = MULTIFILE_MODE_FI;
+	  /* Don't process again files that couldn't
+	     be processed successfully.  */
+	  if (resa[i].res == -1)
+	    continue;
+	  for (cu = alt_first_cu; cu; cu = cu->cu_next)
+	    alt_clear_dups (cu->cu_die);
+	  ret |= dwz (file, NULL, &resa[i],
+		      hardlinks ? resa : NULL, files);
 	}
-      cleanup ();
-      strp_htab = alt_strp_htab;
-      off_htab = alt_off_htab;
-      dup_htab = alt_dup_htab;
-      macro_htab = alt_macro_htab;
-      pool = alt_pool;
-      ob = alt_ob;
-      ob2 = alt_ob2;
-      cleanup ();
+      elf_end (dso->elf);
+      close (multi_fd);
+      free (dso);
     }
 
-  free (resa);
+  cleanup ();
+
+  strp_htab = alt_strp_htab;
+  off_htab = alt_off_htab;
+  dup_htab = alt_dup_htab;
+  macro_htab = alt_macro_htab;
+  pool = alt_pool;
+  ob = alt_ob;
+  ob2 = alt_ob2;
+  cleanup ();
+
+  return ret;
+}
 
+/* Wrapper around dwz_files_1 that takes care of malloc and free of resa.  */
+static int
+dwz_files (int nr_files, char *files[], bool hardlink)
+{
+  int ret;
+  struct file_result *resa
+    = (struct file_result *) malloc ((nr_files) * sizeof (*resa));
+  if (resa == NULL)
+    error (1, ENOMEM, "failed to allocate result array");
+
+  ret = dwz_files_1 (nr_files, files, hardlink, resa);
+
+  free (resa);
   return ret;
 }