From 43527c2cbca46e93061f762353647b742bbdc6d8 Mon Sep 17 00:00:00 2001
From: Bruno Haible <bruno@clisp.org>
Date: Sat, 19 Aug 2000 19:20:04 +0000
Subject: [PATCH] If option -l is given, use memcmp for the comparison.

---
 ChangeLog       |  4 ++++
 src/key-list.cc | 39 ++++++++++++++++++++++++++++++++++++---
 2 files changed, 40 insertions(+), 3 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index b2656b9..ad2714f 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,9 @@
 2000-08-19  Bruno Haible  <bruno@linuix.math.u-bordeaux.fr>
 
+        * src/key-list.cc (Output_Compare_Memcmp): New class.
+          (Key_List::output_lookup_function): When option -l is given, use
+          memcmp instead of strcmp or strncmp.
+
         * doc/gperf.texi: The bug report address is <bug-gnu-utils@gnu.org>.
           The download address is ftp.gnu.org. Remove mention of -a and -g
           options (now nops). Explain effect of -c option.
diff --git a/src/key-list.cc b/src/key-list.cc
index 33c3906..27a2ff8 100644
--- a/src/key-list.cc
+++ b/src/key-list.cc
@@ -810,6 +810,34 @@ void Output_Compare_Strncmp::output_comparison (const Output_Expr& expr1,
   printf ("[len] == '\\0'");
 }
 
+/* This class outputs a comparison using memcmp.
+   Note that the length of expr1 (available through the local variable `len')
+   must be verified to be equal to the length of expr2 prior to this
+   comparison. */
+
+struct Output_Compare_Memcmp : public Output_Compare
+{
+  virtual void output_comparison (const Output_Expr& expr1,
+                                  const Output_Expr& expr2) const;
+  Output_Compare_Memcmp () {}
+  virtual ~Output_Compare_Memcmp () {}
+};
+
+void Output_Compare_Memcmp::output_comparison (const Output_Expr& expr1,
+                                               const Output_Expr& expr2) const
+{
+  T (Trace t ("Output_Compare_Memcmp::output_comparison");)
+  printf ("*");
+  expr1.output_expr ();
+  printf (" == *");
+  expr2.output_expr ();
+  printf (" && !memcmp (");
+  expr1.output_expr ();
+  printf (" + 1, ");
+  expr2.output_expr ();
+  printf (" + 1, len - 1)");
+}
+
 /* ------------------------------------------------------------------------- */
 
 /* Generates C code for the hash function that returns the
@@ -1820,10 +1848,15 @@ Key_List::output_lookup_function (void)
   if (!option[GLOBAL])
     output_lookup_tables ();
 
-  if (option[COMP])
-    output_lookup_function_body (Output_Compare_Strncmp ());
+  if (option[LENTABLE])
+    output_lookup_function_body (Output_Compare_Memcmp ());
   else
-    output_lookup_function_body (Output_Compare_Strcmp ());
+    {
+      if (option[COMP])
+        output_lookup_function_body (Output_Compare_Strncmp ());
+      else
+        output_lookup_function_body (Output_Compare_Strcmp ());
+    }
 
   printf ("}\n");
 }