main.cpp fixes, refactoring (#571)

- main: entering empty line passes back control without new input in interactive/instruct modes
- instruct mode: keep prompt fix
- instruct mode: duplicate instruct prompt fix
- refactor: move common console code from main->common

3 files changed, 143 insertions, 118 deletions

diff --git a/examples/common.cpp b/examples/common.cpp
index 2ab000f..880ebe9 100644
--- a/examples/common.cpp
+++ b/examples/common.cpp
@@ -9,11 +9,20 @@
 #include <iterator>
 #include <algorithm>
 
- #if defined(_MSC_VER) || defined(__MINGW32__)
- #include <malloc.h> // using malloc.h with MSC/MINGW
- #elif !defined(__FreeBSD__) && !defined(__NetBSD__) && !defined(__OpenBSD__)
- #include <alloca.h>
- #endif
+#if defined(_MSC_VER) || defined(__MINGW32__)
+#include <malloc.h> // using malloc.h with MSC/MINGW
+#elif !defined(__FreeBSD__) && !defined(__NetBSD__) && !defined(__OpenBSD__)
+#include <alloca.h>
+#endif
+
+#if defined (_WIN32)
+#pragma comment(lib,"kernel32.lib")
+extern "C" __declspec(dllimport) void* __stdcall GetStdHandle(unsigned long nStdHandle);
+extern "C" __declspec(dllimport) int __stdcall GetConsoleMode(void* hConsoleHandle, unsigned long* lpMode);
+extern "C" __declspec(dllimport) int __stdcall SetConsoleMode(void* hConsoleHandle, unsigned long dwMode);
+extern "C" __declspec(dllimport) int __stdcall SetConsoleCP(unsigned int wCodePageID);
+extern "C" __declspec(dllimport) int __stdcall SetConsoleOutputCP(unsigned int wCodePageID);
+#endif
 
 bool gpt_params_parse(int argc, char ** argv, gpt_params & params) {
     // determine sensible default number of threads.
@@ -204,7 +213,7 @@ void gpt_print_usage(int /*argc*/, char ** argv, const gpt_params & params) {
     fprintf(stderr, "  --in-prefix STRING    string to prefix user inputs with (default: empty)\n");
     fprintf(stderr, "  -f FNAME, --file FNAME\n");
     fprintf(stderr, "                        prompt file to start generation.\n");
-    fprintf(stderr, "  -n N, --n_predict N   number of tokens to predict (default: %d, -1 - infinity)\n", params.n_predict);
+    fprintf(stderr, "  -n N, --n_predict N   number of tokens to predict (default: %d, -1 = infinity)\n", params.n_predict);
     fprintf(stderr, "  --top_k N             top-k sampling (default: %d)\n", params.top_k);
     fprintf(stderr, "  --top_p N             top-p sampling (default: %.1f)\n", params.top_p);
     fprintf(stderr, "  --repeat_last_n N     last n tokens to consider for penalize (default: %d)\n", params.repeat_last_n);
@@ -216,7 +225,7 @@ void gpt_print_usage(int /*argc*/, char ** argv, const gpt_params & params) {
     fprintf(stderr, "  --n_parts N           number of model parts (default: -1 = determine from dimensions)\n");
     fprintf(stderr, "  -b N, --batch_size N  batch size for prompt processing (default: %d)\n", params.n_batch);
     fprintf(stderr, "  --perplexity          compute perplexity over the prompt\n");
-    fprintf(stderr, "  --keep                number of tokens to keep from the initial prompt\n");
+    fprintf(stderr, "  --keep                number of tokens to keep from the initial prompt (default: %d, -1 = all)\n", params.n_keep);
     if (ggml_mlock_supported()) {
         fprintf(stderr, "  --mlock               force system to keep model in RAM rather than swapping or compressing\n");
     }
@@ -256,3 +265,47 @@ std::vector<llama_token> llama_tokenize(struct llama_context * ctx, const std::s
 
     return res;
 }
+
+/* Keep track of current color of output, and emit ANSI code if it changes. */
+void set_console_color(console_state & con_st, console_color_t color) {
+    if (con_st.use_color && con_st.color != color) {
+        switch(color) {
+            case CONSOLE_COLOR_DEFAULT:
+                printf(ANSI_COLOR_RESET);
+                break;
+            case CONSOLE_COLOR_PROMPT:
+                printf(ANSI_COLOR_YELLOW);
+                break;
+            case CONSOLE_COLOR_USER_INPUT:
+                printf(ANSI_BOLD ANSI_COLOR_GREEN);
+                break;
+        }
+        con_st.color = color;
+    }
+}
+
+#if defined (_WIN32)
+void win32_console_init(bool enable_color) {
+    unsigned long dwMode = 0;
+    void* hConOut = GetStdHandle((unsigned long)-11); // STD_OUTPUT_HANDLE (-11)
+    if (!hConOut || hConOut == (void*)-1 || !GetConsoleMode(hConOut, &dwMode)) {
+        hConOut = GetStdHandle((unsigned long)-12); // STD_ERROR_HANDLE (-12)
+        if (hConOut && (hConOut == (void*)-1 || !GetConsoleMode(hConOut, &dwMode))) {
+            hConOut = 0;
+        }
+    }
+    if (hConOut) {
+        // Enable ANSI colors on Windows 10+
+        if (enable_color && !(dwMode & 0x4)) {
+            SetConsoleMode(hConOut, dwMode | 0x4); // ENABLE_VIRTUAL_TERMINAL_PROCESSING (0x4)
+        }
+        // Set console output codepage to UTF8
+        SetConsoleOutputCP(65001); // CP_UTF8
+    }
+    void* hConIn = GetStdHandle((unsigned long)-10); // STD_INPUT_HANDLE (-10)
+    if (hConIn && hConIn != (void*)-1 && GetConsoleMode(hConIn, &dwMode)) {
+        // Set console input codepage to UTF8
+        SetConsoleCP(65001); // CP_UTF8
+    }
+}
+#endif
diff --git a/examples/common.h b/examples/common.h
index 8caefd8..1505aa9 100644
--- a/examples/common.h
+++ b/examples/common.h
@@ -63,3 +63,33 @@ std::string gpt_random_prompt(std::mt19937 & rng);
 //
 
 std::vector<llama_token> llama_tokenize(struct llama_context * ctx, const std::string & text, bool add_bos);
+
+//
+// Console utils
+//
+
+#define ANSI_COLOR_RED     "\x1b[31m"
+#define ANSI_COLOR_GREEN   "\x1b[32m"
+#define ANSI_COLOR_YELLOW  "\x1b[33m"
+#define ANSI_COLOR_BLUE    "\x1b[34m"
+#define ANSI_COLOR_MAGENTA "\x1b[35m"
+#define ANSI_COLOR_CYAN    "\x1b[36m"
+#define ANSI_COLOR_RESET   "\x1b[0m"
+#define ANSI_BOLD          "\x1b[1m"
+
+enum console_color_t {
+    CONSOLE_COLOR_DEFAULT=0,
+    CONSOLE_COLOR_PROMPT,
+    CONSOLE_COLOR_USER_INPUT
+};
+
+struct console_state {
+    bool use_color = false;
+    console_color_t color = CONSOLE_COLOR_DEFAULT;
+};
+
+void set_console_color(console_state & con_st, console_color_t color);
+
+#if defined (_WIN32)
+void win32_console_init(bool enable_color);
+#endif
diff --git a/examples/main/main.cpp b/examples/main/main.cpp
index 66b7c2d..d5ab2cf 100644
--- a/examples/main/main.cpp
+++ b/examples/main/main.cpp
@@ -18,58 +18,13 @@
 #include <signal.h>
 #endif
 
-#if defined (_WIN32)
-#pragma comment(lib,"kernel32.lib")
-extern "C" __declspec(dllimport) void* __stdcall GetStdHandle(unsigned long nStdHandle);
-extern "C" __declspec(dllimport) int __stdcall GetConsoleMode(void* hConsoleHandle, unsigned long* lpMode);
-extern "C" __declspec(dllimport) int __stdcall SetConsoleMode(void* hConsoleHandle, unsigned long dwMode);
-extern "C" __declspec(dllimport) int __stdcall SetConsoleCP(unsigned int wCodePageID);
-extern "C" __declspec(dllimport) int __stdcall SetConsoleOutputCP(unsigned int wCodePageID);
-#endif
-
-#define ANSI_COLOR_RED     "\x1b[31m"
-#define ANSI_COLOR_GREEN   "\x1b[32m"
-#define ANSI_COLOR_YELLOW  "\x1b[33m"
-#define ANSI_COLOR_BLUE    "\x1b[34m"
-#define ANSI_COLOR_MAGENTA "\x1b[35m"
-#define ANSI_COLOR_CYAN    "\x1b[36m"
-#define ANSI_COLOR_RESET   "\x1b[0m"
-#define ANSI_BOLD          "\x1b[1m"
-
-/* Keep track of current color of output, and emit ANSI code if it changes. */
-enum console_state {
-    CONSOLE_STATE_DEFAULT=0,
-    CONSOLE_STATE_PROMPT,
-    CONSOLE_STATE_USER_INPUT
-};
-
-static console_state con_st = CONSOLE_STATE_DEFAULT;
-static bool con_use_color = false;
-
-void set_console_state(console_state new_st) {
-    if (!con_use_color) return;
-    // only emit color code if state changed
-    if (new_st != con_st) {
-        con_st = new_st;
-        switch(con_st) {
-        case CONSOLE_STATE_DEFAULT:
-            printf(ANSI_COLOR_RESET);
-            return;
-        case CONSOLE_STATE_PROMPT:
-            printf(ANSI_COLOR_YELLOW);
-            return;
-        case CONSOLE_STATE_USER_INPUT:
-            printf(ANSI_BOLD ANSI_COLOR_GREEN);
-            return;
-        }
-    }
-}
+static console_state con_st;
 
 static bool is_interacting = false;
 
 #if defined (__unix__) || (defined (__APPLE__) && defined (__MACH__)) || defined (_WIN32)
 void sigint_handler(int signo) {
-    set_console_state(CONSOLE_STATE_DEFAULT);
+    set_console_color(con_st, CONSOLE_COLOR_DEFAULT);
     printf("\n"); // this also force flush stdout.
     if (signo == SIGINT) {
         if (!is_interacting) {
@@ -81,32 +36,6 @@ void sigint_handler(int signo) {
 }
 #endif
 
-#if defined (_WIN32)
-void win32_console_init(void) {
-    unsigned long dwMode = 0;
-    void* hConOut = GetStdHandle((unsigned long)-11); // STD_OUTPUT_HANDLE (-11)
-    if (!hConOut || hConOut == (void*)-1 || !GetConsoleMode(hConOut, &dwMode)) {
-        hConOut = GetStdHandle((unsigned long)-12); // STD_ERROR_HANDLE (-12)
-        if (hConOut && (hConOut == (void*)-1 || !GetConsoleMode(hConOut, &dwMode))) {
-            hConOut = 0;
-        }
-    }
-    if (hConOut) {
-        // Enable ANSI colors on Windows 10+
-        if (con_use_color && !(dwMode & 0x4)) {
-            SetConsoleMode(hConOut, dwMode | 0x4); // ENABLE_VIRTUAL_TERMINAL_PROCESSING (0x4)
-        }
-        // Set console output codepage to UTF8
-        SetConsoleOutputCP(65001); // CP_UTF8
-    }
-    void* hConIn = GetStdHandle((unsigned long)-10); // STD_INPUT_HANDLE (-10)
-    if (hConIn && hConIn != (void*)-1 && GetConsoleMode(hConIn, &dwMode)) {
-        // Set console input codepage to UTF8
-        SetConsoleCP(65001); // CP_UTF8
-    }
-}
-#endif
-
 int main(int argc, char ** argv) {
     gpt_params params;
     params.model = "models/llama-7B/ggml-model.bin";
@@ -115,13 +44,12 @@ int main(int argc, char ** argv) {
         return 1;
     }
 
-
     // save choice to use color for later
     // (note for later: this is a slightly awkward choice)
-    con_use_color = params.use_color;
+    con_st.use_color = params.use_color;
 
 #if defined (_WIN32)
-    win32_console_init();
+    win32_console_init(params.use_color);
 #endif
 
     if (params.perplexity) {
@@ -218,7 +146,10 @@ int main(int argc, char ** argv) {
         return 1;
     }
 
-    params.n_keep    = std::min(params.n_keep,    (int) embd_inp.size());
+    // number of tokens to keep when resetting context
+    if (params.n_keep < 0 || params.n_keep > (int)embd_inp.size() || params.instruct) {
+        params.n_keep = (int)embd_inp.size();
+    }
 
     // prefix & suffix for instruct mode
     const auto inp_pfx = ::llama_tokenize(ctx, "\n\n### Instruction:\n\n", true);
@@ -226,16 +157,12 @@ int main(int argc, char ** argv) {
 
     // in instruct mode, we inject a prefix and a suffix to each input by the user
     if (params.instruct) {
-        params.interactive = true;
+        params.interactive_start = true;
         params.antiprompt.push_back("### Instruction:\n\n");
     }
 
-    // enable interactive mode if reverse prompt is specified
-    if (params.antiprompt.size() != 0) {
-        params.interactive = true;
-    }
-
-    if (params.interactive_start) {
+    // enable interactive mode if reverse prompt or interactive start is specified
+    if (params.antiprompt.size() != 0 || params.interactive_start) { 
         params.interactive = true;
     }
 
@@ -297,17 +224,18 @@ int main(int argc, char ** argv) {
 #endif
                " - Press Return to return control to LLaMa.\n"
                " - If you want to submit another line, end your input in '\\'.\n\n");
-        is_interacting = params.interactive_start || params.instruct;
+        is_interacting = params.interactive_start;
     }
 
-    bool input_noecho = false;
+    bool is_antiprompt = false;
+    bool input_noecho  = false;
 
     int n_past     = 0;
     int n_remain   = params.n_predict;
     int n_consumed = 0;
 
     // the first thing we will do is to output the prompt, so set color accordingly
-    set_console_state(CONSOLE_STATE_PROMPT);
+    set_console_color(con_st, CONSOLE_COLOR_PROMPT);
 
     std::vector<llama_token> embd;
 
@@ -408,36 +336,38 @@ int main(int argc, char ** argv) {
         }
         // reset color to default if we there is no pending user input
         if (!input_noecho && (int)embd_inp.size() == n_consumed) {
-            set_console_state(CONSOLE_STATE_DEFAULT);
+            set_console_color(con_st, CONSOLE_COLOR_DEFAULT);
         }
 
         // in interactive mode, and not currently processing queued inputs;
         // check if we should prompt the user for more
         if (params.interactive && (int) embd_inp.size() <= n_consumed) {
+
             // check for reverse prompt
-            std::string last_output;
-            for (auto id : last_n_tokens) {
-                last_output += llama_token_to_str(ctx, id);
-            }
+            if (params.antiprompt.size()) {
+                std::string last_output;
+                for (auto id : last_n_tokens) {
+                    last_output += llama_token_to_str(ctx, id);
+                }
 
-            // Check if each of the reverse prompts appears at the end of the output.
-            for (std::string & antiprompt : params.antiprompt) {
-                if (last_output.find(antiprompt.c_str(), last_output.length() - antiprompt.length(), antiprompt.length()) != std::string::npos) {
-                    is_interacting = true;
-                    set_console_state(CONSOLE_STATE_USER_INPUT);
-                    fflush(stdout);
-                    break;
+                is_antiprompt = false;
+                // Check if each of the reverse prompts appears at the end of the output.
+                for (std::string & antiprompt : params.antiprompt) {
+                    if (last_output.find(antiprompt.c_str(), last_output.length() - antiprompt.length(), antiprompt.length()) != std::string::npos) {
+                        is_interacting = true;
+                        is_antiprompt = true;
+                        set_console_color(con_st, CONSOLE_COLOR_USER_INPUT);
+                        fflush(stdout);
+                        break;
+                    }
                 }
             }
 
             if (n_past > 0 && is_interacting) {
                 // potentially set color to indicate we are taking user input
-                set_console_state(CONSOLE_STATE_USER_INPUT);
+                set_console_color(con_st, CONSOLE_COLOR_USER_INPUT);
 
                 if (params.instruct) {
-                    n_consumed = embd_inp.size();
-                    embd_inp.insert(embd_inp.end(), inp_pfx.begin(), inp_pfx.end());
-
                     printf("\n> ");
                 }
 
@@ -463,16 +393,28 @@ int main(int argc, char ** argv) {
                 } while (another_line);
 
                 // done taking input, reset color
-                set_console_state(CONSOLE_STATE_DEFAULT);
+                set_console_color(con_st, CONSOLE_COLOR_DEFAULT);
 
-                auto line_inp = ::llama_tokenize(ctx, buffer, false);
-                embd_inp.insert(embd_inp.end(), line_inp.begin(), line_inp.end());
+                // Add tokens to embd only if the input buffer is non-empty
+                // Entering a empty line lets the user pass control back
+                if (buffer.length() > 1) {
 
-                if (params.instruct) {
-                    embd_inp.insert(embd_inp.end(), inp_sfx.begin(), inp_sfx.end());
-                }
+                    // instruct mode: insert instruction prefix
+                    if (params.instruct && !is_antiprompt) {
+                        n_consumed = embd_inp.size();
+                        embd_inp.insert(embd_inp.end(), inp_pfx.begin(), inp_pfx.end());
+                    }
 
-                n_remain -= line_inp.size();
+                    auto line_inp = ::llama_tokenize(ctx, buffer, false);
+                    embd_inp.insert(embd_inp.end(), line_inp.begin(), line_inp.end());
+
+                    // instruct mode: insert response suffix
+                    if (params.instruct) {
+                        embd_inp.insert(embd_inp.end(), inp_sfx.begin(), inp_sfx.end());
+                    }
+
+                    n_remain -= line_inp.size();
+                }
 
                 input_noecho = true; // do not echo this again
             }
@@ -506,7 +448,7 @@ int main(int argc, char ** argv) {
     llama_print_timings(ctx);
     llama_free(ctx);
 
-    set_console_state(CONSOLE_STATE_DEFAULT);
+    set_console_color(con_st, CONSOLE_COLOR_DEFAULT);
 
     return 0;
 }