From c3c5d00fa12281fcf80156d040e471fdc9123aac Mon Sep 17 00:00:00 2001
From: andreymuch <andrey.much@mail.ru>
Date: Sat, 25 May 2024 17:05:31 +0300
Subject: [PATCH] Implementation of stringFormat function

---
 cstring.h | 29 +++++++++++++++++++++++++++++
 1 file changed, 29 insertions(+)

diff --git a/cstring.h b/cstring.h
index 1a76fc5..b8cc547 100644
--- a/cstring.h
+++ b/cstring.h
@@ -6,6 +6,7 @@
 #include <stdbool.h>
 #include <assert.h>
 #include <inttypes.h>
+#include <stdarg.h>
 
 typedef enum EErrorCode {
     ERR_NO_ERROR,
@@ -609,6 +610,34 @@ TString stringSubstring(TString s, size_t pos, size_t len) {
     return res;
 }
 
+TString stringFormat(const char* format, ...) {
+    va_list args;
+    va_start(args, format);
+    va_list args_copy;
+    va_copy(args_copy, args);
+    const int size = vsnprintf(NULL, 0, format, args_copy);
+    va_end(args_copy);
+    if (size < 0) {
+	    const TString error_result = { NULL, 0, 0 };
+        va_end(args);
+        return error_result;
+    }
+    TString result;
+    result.size = size;
+    result.capacity = size + 1;
+    result.data = (char*)malloc(result.capacity);
+
+    if (!result.data) {
+        result.size = 0;
+        result.capacity = 0;
+        va_end(args);
+        return result;
+    }
+    vsnprintf(result.data, result.capacity, format, args);
+    va_end(args);
+    return result;
+}
+
 void stringScan(TString *s) {
     if (s == NULL) {
         setError(ERR_NULL_POINTER);