Adding the ability to cancel an agent midstream

include/ollama_client.hpp

@@ -5,6 +5,7 @@
 #include <vector>
 #include <iostream>
 #include <optional>
+#include <curl/curl.h>
 
 using http_req_cb_t = std::function<std::string(std::string const& old, std::string const& new_str)>;
 
@@ -30,6 +31,11 @@ private:
     nlohmann::json build_body(const std::vector<Message>& messages,
                               const std::vector<Tool>& tools) const;
     static size_t write_cb(char* ptr, size_t size, size_t nmemb, void* userdata);
+    static int xferinfo_cb(void* cookie,
+                       curl_off_t dltotal,
+                       curl_off_t dlnow,
+                       curl_off_t ultotal,
+                       curl_off_t ulnow);
     std::expected<std::string, std::string> http_request(const std::string& full_url, 
                              const std::string& method, 
                              const std::string& body = "",

include/utility.hpp

@@ -2,6 +2,9 @@
 #include <string>
 #include <expected>
 #include <functional>
+#include <atomic>
+
+extern std::atomic<bool> ctrlc_request;
 
 // Trim whitespace from both ends of a string
 std::string trim(const std::string& s);

src/harness.cpp

@@ -2,6 +2,7 @@
 #include "json_types.hpp"
 #include "base64_util.hpp"
 #include <iostream>
+#include "utility.hpp"
 
 Harness::Harness(std::unique_ptr<Client> client, const ToolRegistry& registry,
                  HarnessConfig config)
@@ -80,11 +81,20 @@ std::expected<std::string, std::string> Harness::chat(const Message& user_messag
     push_message(user_message);
 
     for (size_t i = 0; i < config_.max_tool_iterations; ++i) {
+
+        if (ctrlc_request)
+        {
+            return "";
+        }
+
         Message response;
         bool done = false;
         size_t retries = 20;
         while (!done)
         {
+            if (ctrlc_request)
+                return "";
+
             retries--;
             if (retries == 0)
             {

src/main.cpp

@@ -29,6 +29,15 @@
 #include <filesystem>
 #include <random>
 #include <iomanip>
+#include <signal.h>
+
+std::atomic<bool> ctrlc_request;
+
+void signalHandler(int signal) {
+    if (signal == SIGINT) {
+        ctrlc_request = true;
+    }
+}
 
 static const std::vector<AgentProfile> profiles = {
 #if !defined(_WIN32)
@@ -97,6 +106,8 @@ static HarnessState read_harness_state_or_exit(const char* file_path) {
 }
 
 int main(int argc, char** argv) {
+    signal(SIGINT, signalHandler);
+
     OllamaConfig cfg;
     if (const char* m = std::getenv("OLLAMA_MODEL")) cfg.model    = m;
     if (const char* u = std::getenv("OLLAMA_URL"))   cfg.base_url = u;

src/ollama_client.cpp

@@ -4,6 +4,7 @@
 #include <string>
 #include <iostream>
 #include <expected>
+#include "utility.hpp"
 
 static int ollama_clients = 0;
 
@@ -37,6 +38,27 @@ size_t OllamaClient::write_cb(char* ptr, size_t size, size_t nmemb, void* userda
     return size * nmemb;
 }
 
+
+int OllamaClient::xferinfo_cb(void* cookie,
+                       curl_off_t dltotal,
+                       curl_off_t dlnow,
+                       curl_off_t ultotal,
+                       curl_off_t ulnow)
+{
+    (void)cookie;
+    (void)dltotal;
+    (void)dlnow;
+    (void)ultotal;
+    (void)ulnow;
+
+    if (ctrlc_request)
+    {
+        return 1; // Cancel
+    }
+
+    return 0; // Continue transfer
+}
+
 std::expected<std::string, std::string> OllamaClient::http_request(const std::string& full_url, 
                                        const std::string& method, 
                                        const std::string& body,
@@ -70,6 +92,8 @@ std::expected<std::string, std::string> OllamaClient::http_request(const std::st
         headers = curl_slist_append(headers, "Content-Type: application/json");
 
     curl_easy_setopt(curl, CURLOPT_URL, url.c_str());
+    curl_easy_setopt(curl, CURLOPT_XFERINFOFUNCTION, xferinfo_cb);
+    curl_easy_setopt(curl, CURLOPT_NOPROGRESS, 0L);
     curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, write_cb);
     curl_easy_setopt(curl, CURLOPT_WRITEDATA, &response_buf);
     curl_easy_setopt(curl, CURLOPT_HTTPHEADER, headers);