utils: added string concatination function

2 files changed, 26 insertions, 0 deletions

diff --git a/src/modules/utils/utils.c b/src/modules/utils/utils.c
index d5a3a96..2e8aa5c 100644
--- a/src/modules/utils/utils.c
+++ b/src/modules/utils/utils.c
@@ -1,3 +1,4 @@
+#include <stdio.h>
 #include <string.h>
 #include <stdlib.h>
 
@@ -93,3 +94,21 @@ char *string_format(char* string) {
 
     return ptr;
 }
+
+// input two char pointer
+// output: one char pointer
+// misc: caller needs to free the memory
+char *concat(const char *s1, const char *s2) {
+    const size_t len1 = strlen(s1);
+    const size_t len2 = strlen(s2);
+    char *result = malloc(len1 + len2 + 1); // +1 for '\0'
+    
+    if (result == NULL) {
+	perror("allocating memory for strings failed");
+	return NULL;
+    }
+
+    memcpy(result, s1, len1);
+    memcpy(result + len1, s2, len2 + 1); // +1 for null-terminator
+    return result; //caller needs to free memory
+}
diff --git a/src/modules/utils/utils.h b/src/modules/utils/utils.h
index 1dfbb51..7a0ab02 100644
--- a/src/modules/utils/utils.h
+++ b/src/modules/utils/utils.h
@@ -11,4 +11,11 @@
  */
 char *string_format(char* string);
 
+// function: char *concat(const char *str1, const char *str2)
+// input two char pointer
+// return: pointer to string
+// on-error: returns NULL
+// misc: caller needs to free the memory
+char *concat(const char *str1, const char *str2);
+
 #endif