s390-tools: Move function util_strstrip

This patch
 - moves function util_strstrip to libutil/util_libc.c and deletes the
   extra files util_strstip.[ch]
 - adds doxygen comments for util_strstrip()
 - provides an example on how to use util_strstrip().

Signed-off-by: Thomas Richter <tmricht@linux.vnet.ibm.com>
Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>

libutil/Makefile

@@ -26,8 +26,7 @@ objects =	util_base.o \
 		util_part.o \
 		util_prg.o \
 		util_proc.o \
-		util_rec.o \
-		util_str.o
+		util_rec.o
 
 util_base_example: util_base_example.o $(lib)
 util_panic_example: util_panic_example.o $(lib)

libutil/util_libc.c

@@ -198,3 +198,33 @@ int __util_vsprintf(const char *func, const char *file, int line,
 			      rc != -1, "Could not format string\n");
 	return rc;
 }
+
+/**
+ * Strip leading and trailing spaces from string
+ *
+ * Remove string \a s leading and trailing spaces
+ *
+ * @param[in,out] s String to manipulate
+ *
+ * @returns Pointer to first non-space character in string \a s
+ */
+char *util_strstrip(char *s)
+{
+	size_t size;
+	char *end;
+
+	size = strlen(s);
+
+	if (!size)
+		return s;
+
+	end = s + size - 1;
+	while (end >= s && isspace(*end))
+		end--;
+	*(end + 1) = '\0';
+
+	while (*s && isspace(*s))
+		s++;
+
+	return s;
+}

libutil/util_libc_example.c

@@ -10,10 +10,13 @@
 //! [code]
 #include <stdio.h>
 #include <stdlib.h>
+#include <string.h>
 
 #include "lib/util_libc.h"
 #include "lib/util_panic.h"
 
+#define	EXAMPLE_WORD	"   /sys/devices/system/cpu    "
+
 /*
  * Demonstrate that out of memory is automatically handled via panic()
  */
@@ -22,6 +25,12 @@ int main(void)
 	unsigned long ulong_max = (unsigned long)-1;
 	void *ptr;
 	char *zeroes, *str;
+	char buffer[sizeof(EXAMPLE_WORD)];
+
+	strcat(buffer, EXAMPLE_WORD);
+	fprintf(stderr, "Try to remove leading and trailing spaces from "
+			"\"%s\"\nresult = \"%s\"\n", EXAMPLE_WORD,
+			util_strstrip(buffer));
 
 	/* Use util_strcat_realloc() for string concatenation */
 	fprintf(stderr, "Try to concatenate \"Hello\",  \", \" and \"world!\": ");

libutil/util_str.c

@@ -1,39 +0,0 @@
-/*
- * util - Utility function library
- *
- * Strip leading and trailing blanks.
- *
- * Copyright IBM Corp. 2018
- *
- * s390-tools is free software; you can redistribute it and/or modify
- * it under the terms of the MIT license. See LICENSE for details.
- */
-
-#include <string.h>
-#include <ctype.h>
-
-#include "lib/util_str.h"
-
-/*
- * strip leading and trailing blanks
- */
-char *util_strstrip(char *s)
-{
-	size_t size;
-	char *end;
-
-	size = strlen(s);
-
-	if (!size)
-		return s;
-
-	end = s + size - 1;
-	while (end >= s && isspace(*end))
-		end--;
-	*(end + 1) = '\0';
-
-	while (*s && isspace(*s))
-		s++;
-
-	return s;
-}