Revert "fastfetch: add the missing new-line in config files (#772)"

Fix #778

This reverts commit 4430b71.

Author: CarterLi

src/fastfetch.c

@@ -821,7 +821,6 @@ static void run(FFdata* data)
     if (instance.state.resultDoc)
     {
         yyjson_mut_write_fp(stdout, instance.state.resultDoc, YYJSON_WRITE_INF_AND_NAN_AS_NULL | YYJSON_WRITE_PRETTY_TWO_SPACES, NULL, NULL);
-        //TODO should use YYJSON_WRITE_NEWLINE_AT_END when it is available
         putchar('\n');
     }
     else
@@ -841,23 +840,24 @@ static void writeConfigFile(FFdata* data, const FFstrbuf* filename)
     ffOptionsGenerateLibraryJsonConfig(&instance.config.library, doc);
     ffMigrateCommandOptionToJsonc(data, doc);
 
-    FILE *fp = stdout;
-    bool writeToStdout = ffStrbufEqualS(filename, "-");
-    if (!writeToStdout)
-        fp = fopen(filename->chars, "w");
-
-    bool ok = yyjson_mut_write_fp(fp, doc, YYJSON_WRITE_INF_AND_NAN_AS_NULL | YYJSON_WRITE_PRETTY_TWO_SPACES, NULL, NULL);
-    //TODO should use YYJSON_WRITE_NEWLINE_AT_END when it is available
-    fputc('\n', fp);
-    if (!ok)
-    {
-        fprintf(stderr, "Error: failed to generate config in `%s`\n", writeToStdout ? "stdout" : filename->chars);
-        exit(1);
-    }
-    if (ok && !writeToStdout)
+    if (ffStrbufEqualS(filename, "-"))
+        yyjson_mut_write_fp(stdout, doc, YYJSON_WRITE_INF_AND_NAN_AS_NULL | YYJSON_WRITE_PRETTY_TWO_SPACES, NULL, NULL);
+    else
     {
-        fclose(fp);
-        printf("The generated config file has been written in `%s`\n", filename->chars);
+        size_t len;
+        FF_AUTO_FREE const char* str = yyjson_mut_write(doc, YYJSON_WRITE_INF_AND_NAN_AS_NULL | YYJSON_WRITE_PRETTY_TWO_SPACES, &len);
+        if (!str)
+        {
+            printf("Error: failed to generate config file\n");
+            exit(1);
+        }
+        if (ffWriteFileData(filename->chars, len, str))
+            printf("The generated config file has been written in `%s`\n", filename->chars);
+        else
+        {
+            printf("Error: failed to write file in `%s`\n", filename->chars);
+            exit(1);
+        }
     }
 
     yyjson_mut_doc_free(doc);