fix clear memory

Author: ngxson

tools/mtmd/mtmd-cli.cpp

@@ -80,6 +80,7 @@ struct mtmd_cli_context {
     common_chat_templates_ptr tmpls;
     std::vector<common_chat_msg> chat_history;
     bool use_jinja = false;
+    std::string system_prompt;
 
     // support for legacy templates (models not having EOT token)
     llama_tokens antiprompt_tokens;
@@ -110,12 +111,8 @@ struct mtmd_cli_context {
 
         tmpls = common_chat_templates_init(model, params.chat_template);
         use_jinja = params.use_jinja;
-        if (!params.system_prompt.empty()) {
-            common_chat_msg sys_msg;
-            sys_msg.role    = "system";
-            sys_msg.content = params.system_prompt;
-            chat_history.push_back(std::move(sys_msg));
-        }
+        system_prompt = params.system_prompt;
+        reset_chat_history();
         LOG_INF("%s: chat template example:\n%s\n", __func__, common_chat_format_example(tmpls.get(), params.use_jinja, params.default_template_kwargs).c_str());
 
         init_vision_context(params);
@@ -133,6 +130,16 @@ struct mtmd_cli_context {
         common_sampler_free(smpl);
     }
 
+    void reset_chat_history() {
+        chat_history.clear();
+        if (!system_prompt.empty()) {
+            common_chat_msg sys_msg;
+            sys_msg.role    = "system";
+            sys_msg.content = system_prompt;
+            chat_history.push_back(std::move(sys_msg));
+        }
+    }
+
     void init_vision_context(common_params & params) {
         const char * clip_path = params.mmproj.path.c_str();
         mtmd_context_params mparams = mtmd_context_params_default();
@@ -363,7 +370,8 @@ int main(int argc, char ** argv) {
             }
             if (line == "/clear") {
                 ctx.n_past = 0;
-                llama_memory_seq_rm(llama_get_memory(ctx.lctx), 0, 1, -1); // keep BOS
+                ctx.reset_chat_history();
+                llama_memory_clear(llama_get_memory(ctx.lctx), true);
                 LOG("Chat history cleared\n\n");
                 continue;
             }