common : change --color to accept on/off/auto, default to auto (#17827)

common/arg.cpp

@@ -708,6 +708,8 @@ common_params_context common_params_parser_init(common_params & params, llama_ex
         params.use_jinja = true;
     }
 
+    params.use_color = tty_can_use_colors();
+
     // load dynamic backends
     ggml_backend_load_all();
 
@@ -790,10 +792,20 @@ common_params_context common_params_parser_init(common_params & params, llama_ex
         }
     ).set_examples({LLAMA_EXAMPLE_MAIN}));
     add_opt(common_arg(
-        {"-co", "--color"},
-        string_format("colorise output to distinguish prompt and user input from generations (default: %s)", params.use_color ? "true" : "false"),
-        [](common_params & params) {
-            params.use_color = true;
+        {"-co", "--color"}, "[on|off|auto]",
+        "Colorize output to distinguish prompt and user input from generations ('on', 'off', or 'auto', default: 'auto')\n"
+        "'auto' enables colors when output is to a terminal",
+        [](common_params & params, const std::string & value) {
+            if (is_truthy(value)) {
+                params.use_color = true;
+            } else if (is_falsey(value)) {
+                params.use_color = false;
+            } else if (is_autoy(value)) {
+                params.use_color = tty_can_use_colors();
+            } else {
+                throw std::invalid_argument(
+                    string_format("error: unknown value for --color: '%s'\n", value.c_str()));
+            }
         }
     ).set_examples({LLAMA_EXAMPLE_MAIN, LLAMA_EXAMPLE_SPECULATIVE, LLAMA_EXAMPLE_LOOKUP}));
     add_opt(common_arg(
@@ -1022,7 +1034,7 @@ common_params_context common_params_parser_init(common_params & params, llama_ex
                                params.flash_attn_type = LLAMA_FLASH_ATTN_TYPE_AUTO;
                            } else {
                                throw std::runtime_error(
-                                   string_format("error: unkown value for --flash-attn: '%s'\n", value.c_str()));
+                                   string_format("error: unknown value for --flash-attn: '%s'\n", value.c_str()));
                            }
                        }).set_env("LLAMA_ARG_FLASH_ATTN"));
     add_opt(common_arg(
@@ -2696,7 +2708,7 @@ common_params_context common_params_parser_init(common_params & params, llama_ex
                 common_log_set_colors(common_log_main(), LOG_COLORS_AUTO);
             } else {
                 throw std::invalid_argument(
-                    string_format("error: unkown value for --log-colors: '%s'\n", value.c_str()));
+                    string_format("error: unknown value for --log-colors: '%s'\n", value.c_str()));
             }
         }
     ).set_env("LLAMA_LOG_COLORS"));

common/common.cpp

@@ -982,6 +982,32 @@ std::vector<common_file_info> fs_list(const std::string & path, bool include_dir
     return files;
 }
 
+//
+// TTY utils
+//
+
+bool tty_can_use_colors() {
+    // Check NO_COLOR environment variable (https://no-color.org/)
+    if (const char * no_color = std::getenv("NO_COLOR")) {
+        if (no_color[0] != '\0') {
+            return false;
+        }
+    }
+
+    // Check TERM environment variable
+    if (const char * term = std::getenv("TERM")) {
+        if (std::strcmp(term, "dumb") == 0) {
+            return false;
+        }
+    }
+
+    // Check if stdout and stderr are connected to a terminal
+    // We check both because log messages can go to either
+    bool stdout_is_tty = isatty(fileno(stdout));
+    bool stderr_is_tty = isatty(fileno(stderr));
+
+    return stdout_is_tty || stderr_is_tty;
+}
 
 //
 // Model utils

common/common.h

@@ -655,6 +655,13 @@ struct common_file_info {
 };
 std::vector<common_file_info> fs_list(const std::string & path, bool include_directories);
 
+//
+// TTY utils
+//
+
+// Auto-detect if colors can be enabled based on terminal and environment
+bool tty_can_use_colors();
+
 //
 // Model utils
 //

common/log.cpp

@@ -1,3 +1,4 @@
+#include "common.h"
 #include "log.h"
 
 #include <chrono>
@@ -26,30 +27,6 @@ void common_log_set_verbosity_thold(int verbosity) {
     common_log_verbosity_thold = verbosity;
 }
 
-// Auto-detect if colors should be enabled based on terminal and environment
-static bool common_log_should_use_colors_auto() {
-    // Check NO_COLOR environment variable (https://no-color.org/)
-    if (const char * no_color = std::getenv("NO_COLOR")) {
-        if (no_color[0] != '\0') {
-            return false;
-        }
-    }
-
-    // Check TERM environment variable
-    if (const char * term = std::getenv("TERM")) {
-        if (std::strcmp(term, "dumb") == 0) {
-            return false;
-        }
-    }
-
-    // Check if stdout and stderr are connected to a terminal
-    // We check both because log messages can go to either
-    bool stdout_is_tty = isatty(fileno(stdout));
-    bool stderr_is_tty = isatty(fileno(stderr));
-
-    return stdout_is_tty || stderr_is_tty;
-}
-
 static int64_t t_us() {
     return std::chrono::duration_cast<std::chrono::microseconds>(std::chrono::system_clock::now().time_since_epoch()).count();
 }
@@ -391,7 +368,7 @@ struct common_log * common_log_main() {
     static std::once_flag    init_flag;
     std::call_once(init_flag, [&]() {
         // Set default to auto-detect colors
-        log.set_colors(common_log_should_use_colors_auto());
+        log.set_colors(tty_can_use_colors());
     });
 
     return &log;
@@ -422,7 +399,7 @@ void common_log_set_file(struct common_log * log, const char * file) {
 
 void common_log_set_colors(struct common_log * log, log_colors colors) {
     if (colors == LOG_COLORS_AUTO) {
-        log->set_colors(common_log_should_use_colors_auto());
+        log->set_colors(tty_can_use_colors());
         return;
     }