From 39e1fb9e5a5b11ee3e11e3fa0329a6053a870eac Mon Sep 17 00:00:00 2001
From: Cheer Xiao <xiaqqaix@gmail.com>
Date: Tue, 8 Jan 2013 22:40:28 +0800
Subject: [PATCH] sort: Get rid of global comparer

---
 src/dhcpd-pools.h |  3 +--
 src/sort.c        | 27 +++++++++++----------------
 2 files changed, 12 insertions(+), 18 deletions(-)

diff --git a/src/dhcpd-pools.h b/src/dhcpd-pools.h
index 6b175ac..0aa9210 100644
--- a/src/dhcpd-pools.h
+++ b/src/dhcpd-pools.h
@@ -223,11 +223,10 @@ int leasecomp(const void *restrict a, const void *restrict b);
 int rangecomp(const void *__restrict r1, const void *__restrict r2)
     __attribute__ ((nonnull(1, 2)));
 /* sort function pointer and functions */
-int (*comparer) (struct range_t *r1, struct range_t *r2);
+typedef int (*comparer_t) (struct range_t *r1, struct range_t *r2);
 unsigned long int ret_percent(struct range_t r);
 unsigned long int ret_tc(struct range_t r);
 unsigned long int ret_tcperc(struct range_t r);
-void field_selector(char c);
 void mergesort_ranges(struct range_t *__restrict orig, int size,
 		      struct range_t *__restrict temp)
     __attribute__ ((nonnull(1, 3)));
diff --git a/src/sort.c b/src/sort.c
index 5415359..cdf3d9f 100644
--- a/src/sort.c
+++ b/src/sort.c
@@ -196,33 +196,27 @@ unsigned long int ret_tcperc(struct range_t r)
  * The sort algorithms are stabile, which means multiple sorts can be
  * specified and they do not mess the result of previous sort.  The sort
  * algorithms are used via function pointer, that gets to be reassigned.
+ * \return Return the selected compare function.
  */
-void field_selector(char c)
+comparer_t field_selector(char c)
 {
 	switch (c) {
 	case 'n':
 		break;
 	case 'i':
-		comparer = comp_ip;
-		break;
+		return comp_ip;
 	case 'm':
-		comparer = comp_max;
-		break;
+		return comp_max;
 	case 'c':
-		comparer = comp_cur;
-		break;
+		return comp_cur;
 	case 'p':
-		comparer = comp_percent;
-		break;
+		return comp_percent;
 	case 't':
-		comparer = comp_touched;
-		break;
+		return comp_touched;
 	case 'T':
-		comparer = comp_tc;
-		break;
+		return comp_tc;
 	case 'e':
-		comparer = comp_tcperc;
-		break;
+		return comp_tcperc;
 	default:
 		warnx("field_selector: unknown sort order `%c'", c);
 		errx(EXIT_FAILURE, "Try `%s --help' for more information.",
@@ -238,6 +232,7 @@ void field_selector(char c)
 static int merge(struct range_t *restrict left, struct range_t *restrict right)
 {
 	int i, len, ret;
+	comparer_t comparer;
 	int cmp;
 
 	len = strlen(config.sort);
@@ -255,7 +250,7 @@ static int merge(struct range_t *restrict left, struct range_t *restrict right)
 		}
 
 		/* Select which function is pointed by comparer */
-		field_selector(config.sort[i]);
+		comparer = field_selector(config.sort[i]);
 		cmp = comparer(left, right);
 		/* If fields are equal use next sort method */
 		if (cmp == 0) {