Move string trim functions to util.c

CMakeLists.txt

@@ -73,6 +73,7 @@ set(mbusd_SOURCES
         src/state.c
         src/sig.c
         src/sock.c
+        src/util.c
         )
 add_executable(mbusd ${mbusd_SOURCES})
 install(TARGETS mbusd DESTINATION bin)

src/cfg.c

@@ -34,9 +34,10 @@
 #include "cfg.h"
 
 #include <stdlib.h>
-#include <ctype.h>
 #include <string.h>
 
+#include "util.h"
+
 #define CFG_MAX_LINE_LENGTH 200
 
 #define CFG_NAME_MATCH(n) strcmp(n, name) == 0
@@ -81,37 +82,6 @@ cfg_init(void)
   cfg.replyonbroadcast=0;
 }
 
-static char *
-cfg_rtrim(char *s)
-{
-  char *p = s + strlen(s);
-  while (p > s && isspace((unsigned char )(*--p)))
-    *p = '\0';
-  return s;
-}
-
-static char *
-cfg_ltrim(const char *s)
-{
-  while (*s && isspace((unsigned char )(*s)))
-    s++;
-  return (char *) s;
-}
-
-static int
-cfg_is_empty(char *s)
-{
-  char *p = s + strlen(s);
-  if (strlen(s) == 0)
-    return 1;
-  while (p > s && isspace((unsigned char )(*--p)))
-  { //no-op
-  }
-  if (p == s && isspace((unsigned char )(*p)))
-    return 1;
-  return 0;
-}
-
 int
 cfg_handle_param(char *name, char *value)
 {
@@ -255,15 +225,15 @@ cfg_handle_param(char *name, char *value)
     { /* report about invalid log level */
       CFG_ERR("invalid loglevel value: %s (must be 0-2)", value);
 #  endif
-      return(0);
+      return 0;
     }
   }
   else if (CFG_NAME_MATCH("logfile"))
   {
-    if (cfg_is_empty(value))
+    if (!strlen(value))
     {
       CFG_ERR("missing logfile value", value);
-      return(0);
+      return 0;
     }
     else if (*value != '/')
     {
@@ -279,9 +249,6 @@ cfg_handle_param(char *name, char *value)
       }
     }
     else strncpy(cfg.logname, value, INTBUFSIZE);
-
-
-    
 #endif
   }
   else {
@@ -315,7 +282,7 @@ cfg_parse_file(void *file)
   {
     lineno++;
 
-    start = cfg_ltrim(cfg_rtrim(line));
+    start = util_trim(line);
 
     if (*start == '#')
     {
@@ -330,8 +297,8 @@ cfg_parse_file(void *file)
       {
         *end = '\0';
 
-        name = cfg_rtrim(start);
-        value = cfg_ltrim(cfg_rtrim(end + 1));
+        name = util_rtrim(start);
+        value = util_trim(end + 1);
 
         /* handle name/value pair */
         if (!cfg_handle_param(name, value))

src/util.c

@@ -0,0 +1,80 @@
+/*
+ * OpenMODBUS/TCP to RS-232/485 MODBUS RTU gateway
+ *
+ * util.h - utility functions
+ *
+ * Copyright (c) 2002-2023, Victor Antonovich (v.antonovich@gmail.com)
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * - Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *
+ * - Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "util.h"
+
+#include <ctype.h>
+#include <string.h>
+
+/**
+ * Removes leading whitespace from the string. 
+ * Parameters: s - the string to be trimmed.
+ * Return: a pointer to the first non-whitespace character in string.
+ */
+char *
+util_ltrim(const char *s)
+{
+  while (*s && isspace((unsigned char )(*s)))
+    s++;
+  return (char *) s;
+}
+
+/**
+ * Removes trailing whitespace from the string. 
+ * The first trailing whitespace is replaced with a NUL-terminator
+ * in the given string.
+ * Parameters: s - the string to be trimmed.
+ * Return: a pointer to the string.
+ */
+char *
+util_rtrim(char *s)
+{
+  char *p = s + strlen(s);
+  while (p > s && isspace((unsigned char )(*--p)))
+    *p = '\0';
+  return s;
+}
+
+/**
+ * Removes leading and trailing whitespace from the string. 
+ * The first trailing whitespace is replaced with a NUL-terminator
+ * in the given string.
+ * Parameters: s - the string to be trimmed.
+ * Return: a pointer to the first non-whitespace character in string.
+ */
+char *
+util_trim(char *s)
+{
+	if (!strlen(s))
+		return s;
+
+	return util_ltrim(util_rtrim(s));
+}

src/util.h

@@ -0,0 +1,39 @@
+/*
+ * OpenMODBUS/TCP to RS-232/485 MODBUS RTU gateway
+ *
+ * util.h - utility functions
+ *
+ * Copyright (c) 2002-2023, Victor Antonovich (v.antonovich@gmail.com)
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * - Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *
+ * - Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef _UTIL_H
+#define _UTIL_H
+
+char *util_ltrim(const char *s);
+char *util_rtrim(char *s);
+char *util_trim(char *s);
+
+#endif /* _UTIL_H */