Initial commit

Co-authored-by: Zhuohan Li <zhuohan@openai.com>
Co-authored-by: Maratyszcza <marat@openai.com>
Co-authored-by: Volodymyr Kyrylov <vol@wilab.org.ua>

gpt_oss/metal/source/log.c

@@ -0,0 +1,50 @@
+#include <assert.h>  // assert
+#include <stdarg.h>  // va_list, va_copy, va_end
+#include <stdio.h>  // vsnprintf
+#include <stdlib.h>  // malloc, free
+
+#include <unistd.h>  // STDERR_FILENO
+
+
+
+#define GPTOSS_ON_STACK_FORMAT_BUFFER_SIZE 16384
+
+void gptoss_format_log(const char* format, va_list args) {
+    char stack_buffer[GPTOSS_ON_STACK_FORMAT_BUFFER_SIZE];
+    char* heap_buffer = NULL;
+
+    va_list args_copy;
+    va_copy(args_copy, args);
+
+    const int vsnprintf_result = vsnprintf(stack_buffer, GPTOSS_ON_STACK_FORMAT_BUFFER_SIZE, format, args);
+    assert(vsnprintf_result >= 0);
+
+    // At least a partially formatted buffer is ready.
+    char* message_buffer = &stack_buffer[0];
+    size_t message_size = (size_t) vsnprintf_result;
+    if (message_size > GPTOSS_ON_STACK_FORMAT_BUFFER_SIZE) {
+        heap_buffer = malloc(message_size);
+        if (heap_buffer == NULL) {
+            // Fall back to the truncated message in the on-stack buffer.
+            message_size = GPTOSS_ON_STACK_FORMAT_BUFFER_SIZE;
+        } else {
+            // Use the full message in the in-heap buffer.
+            vsnprintf(heap_buffer, message_size, format, args_copy);
+            message_buffer = heap_buffer;
+        }
+    }
+
+    ssize_t bytes_written;
+    do {
+        bytes_written = write(STDERR_FILENO, message_buffer, message_size);
+        if (bytes_written > 0) {
+            assert((size_t) bytes_written <= message_size);
+            message_buffer += bytes_written;
+            message_size -= bytes_written;
+        }
+    } while (bytes_written >= 0 && message_size != 0);
+
+cleanup:
+    free(heap_buffer);
+    va_end(args_copy);
+}