add log_callback to llama_context_params for custom logging. (#2234)

* add log_callback to llama_context_params for custom logging.

* Fix macro expansion on gcc

* Add struct llama_state for global variables and move log_callback there

* Turn log level into enum and some minor changes.

* Remove model_for_logging parameter (not needed anymore)

* Convert remaining fprintf(stderr, ...) calls to use new macros.

* Fix enum and initialize g_state

* Fix log calls after merge

* Fix missing static

* Add back all the new lines in the logging strings

* Add comment for llama_log_callback and replace remaining printf calls

---------

Co-authored-by: grahameth <->
Co-authored-by: Helmut <helmut.buhler@inf.h-brs.de>

1 files changed, 18 insertions, 1 deletions

diff --git a/llama.h b/llama.h
index fa1977f..d237bcc 100644
--- a/llama.h
+++ b/llama.h
@@ -86,7 +86,20 @@ extern "C" {
 
     typedef void (*llama_progress_callback)(float progress, void *ctx);
 
-   struct llama_context_params {
+    enum llama_log_level {
+        LLAMA_LOG_LEVEL_ERROR = 2,
+        LLAMA_LOG_LEVEL_WARN  = 3,
+        LLAMA_LOG_LEVEL_INFO  = 4
+    };
+
+    // Signature for logging events
+    // Note that text includes the new line character at the end for most events.
+    // If your logging mechanism cannot handle that, check if the last character is '\n' and strip it
+    // if it exists.
+    // It might not exist for progress report where '.' is output repeatedly.
+    typedef void (*llama_log_callback)(llama_log_level level, const char * text, void * user_data);
+
+    struct llama_context_params {
         uint32_t seed;         // RNG seed, -1 for random
         int32_t  n_ctx;        // text context
         int32_t  n_batch;      // prompt processing batch size
@@ -195,6 +208,10 @@ extern "C" {
         int32_t n_eval;
     };
 
+    // Set callback for all future logging events.
+    // If this is not called, or NULL is supplied, everything is output on stderr.
+    LLAMA_API void llama_log_set(llama_log_callback log_callback, void * user_data);
+
     LLAMA_API int llama_max_devices();
 
     LLAMA_API struct llama_context_params llama_context_default_params();