strbuf.c: use memrchr in strbuf_rchop

Makefile

@@ -16,7 +16,7 @@ ifdef DEBUG
 endif
 
 obj := $(obj-ini) $(obj-log) $(obj-notify) $(obj-path) \
-	   $(obj-strbuf) $($obj-xalloc)
+	   $(obj-strbuf) $($obj-xalloc) $(obj-compat)
 
 ifeq ($(database), mongo)
 	LDFLAGS += -lmongoc -lbson

Makefile.include

@@ -15,6 +15,9 @@ ifeq ($(VERBOSE), 2)
 endif
 
 # modules definitions
+ifdef NO_MEMRCHR
+	obj-compat = src/compat/memrchr.o
+endif
 obj-xalloc = src/xalloc.o src/die.o
 obj-strbuf = src/strbuf.o $(obj-xalloc)
 obj-path = src/path.o $(obj-strbuf)

Makefile.local.mk-dist

@@ -10,3 +10,6 @@
 # how to install the libray and header files by yourself.
 # database = mysql
 # database = mongo
+
+# Uncomment this if you don't have memrchr on your system. (GNU extension as of >=glibc 2.1.91)
+# NO_MEMRCHR = 1

src/strbuf.c

@@ -9,7 +9,7 @@
  */
 
 #include <ctype.h>
-#include <string.h>
+#include "compat/string.h"
 #include "xalloc.h"
 #include "strbuf.h"
 
@@ -111,15 +111,11 @@ void strbuf_append_repeat(strbuf_t *s, char ch, size_t len) {
 
 void strbuf_rchop(strbuf_t *s, char ch) {
 
-    int i;
+    char *n = memrchr(s->buf, ch, s->len);
 
-    for(i=s->len-1; i >= 0; i--) {
-
-        if (s->buf[i] == ch) {
-            s->buf[i] = '\0';
-            s->len = i;
-            break;
-        }
+    if (n) {
+        *n = '\0';
+        s->len = n - s->buf;
     }
 }