Add String module

src/String.c

@@ -0,0 +1,63 @@
+#include "String.h"
+#include <string.h>
+
+String * String_new(const char * s)
+{
+    String * new_st = (String *)malloc(sizeof(String));
+    size_t size = strlen(s);
+    if (size != 0u)
+    {
+        char * smem = (char *)malloc(size);
+        memcpy(smem, s, size);
+        new_st->value = smem;
+    }
+    else
+    {
+        new_st->value = NULL;
+    }
+    new_st->size = size;
+    return new_st;
+}
+
+String * String_plus(const String * st, const char * s)
+{
+    String * new_st = (String *)malloc(sizeof(String));
+    size_t size1 = st->size;
+    size_t size2 = strlen(s);
+    size_t size = size1 + size2;
+    char * smem = (char *)malloc(size);
+    memcpy(smem, st->value, size1);
+    memcpy(&smem[size1], s, size2);
+    new_st->value = smem;
+    new_st->size = size;
+    return new_st;
+}
+
+String * String_concat(String * st, const char * s)
+{
+    size_t size2 = strlen(s);
+    size_t size = st->size + size2;
+    char * smem = NULL;
+    if (size != 0u)
+    {
+        smem = (char *)malloc(size);
+        memcpy(smem, st->value, st->size);
+        memcpy(&smem[st->size], s, size2);
+    }
+    if (st->value != NULL)
+    {
+        free(st->value);
+    }
+    st->value = smem;
+    st->size = size;
+    return st;
+}
+
+void String_free(String * st)
+{
+    if (st->value != NULL)
+    {
+        free(st->value);
+    }
+    free(st);
+}

src/String.h

@@ -0,0 +1,19 @@
+#ifndef STRING_H
+#define STRING_H
+
+#include <stdlib.h>
+
+typedef struct
+{
+    char * value;
+    size_t size;
+} String;
+
+String * String_new(const char * s);
+String * String_plus(const String * st, const char * s);
+String * String_concat(String * st, const char * s);
+static inline char * String_cstr(const String * st) { return st->value; }
+static inline size_t String_size(const String * st) { return st->size; }
+void String_free(String * st);
+
+#endif