Add str_startswith and str_endswith

(cherry picked from commit 746d3d6b1a)

src/base/system.c

@@ -1951,6 +1951,30 @@ int str_comp_filenames(const char *a, const char *b)
 	return tolower(*a) - tolower(*b);
 }
 
+const char *str_startswith(const char *str, const char *prefix)
+{
+	int prefixl = str_length(prefix);
+	if(str_comp_num(str, prefix, prefixl) == 0)
+	{
+		return str + prefixl;
+	}
+	else
+	{
+		return 0;
+	}
+}
+
+int str_endswith(const char *str, const char *suffix)
+{
+	int strl = str_length(str);
+	int suffixl = str_length(suffix);
+	if(strl < suffixl)
+	{
+		return 0;
+	}
+	return str_comp(str + strl - suffixl, suffix) == 0;
+}
+
 const char *str_find_nocase(const char *haystack, const char *needle)
 {
 	while(*haystack) /* native implementation */

src/base/system.h

@@ -1013,6 +1013,40 @@ int str_comp_num(const char *a, const char *b, const int num);
 */
 int str_comp_filenames(const char *a, const char *b);
 
+/*
+	Function: str_startswith
+		Checks whether the string begins with a certain prefix.
+
+	Parameter:
+		str - String to check.
+		prefix - Prefix to look for.
+
+	Returns:
+		A pointer to the string str after the string prefix, or 0 if
+		the string prefix isn't a prefix of the string str.
+
+	Remarks:
+		- The strings are treated as zero-terminated strings.
+*/
+const char *str_startswith(const char *str, const char *prefix);
+
+/*
+	Function: str_endswith
+		Checks whether the string ends with a certain suffix.
+
+	Parameter:
+		str - String to check.
+		suffix - Suffix to look for.
+
+	Returns:
+		0 - String suffix is not a suffix of string str
+		1 - String suffix is a suffix of string str
+
+	Remarks:
+		- The strings are treated as zero-terminated strings.
+*/
+int str_endswith(const char *str, const char *suffix);
+
 /*
 	Function: str_find_nocase
 		Finds a string inside another string case insensitive.