Feat xprintf

include/bfdev/xprintf.h

@@ -0,0 +1,40 @@
+/* SPDX-License-Identifier: LGPL-3.0-or-later */
+/*
+ * Copyright(c) 2025 John Sanpe <sanpeqf@gmail.com>
+ */
+
+#ifndef _BFDEV_XPRINTF_H_
+#define _BFDEV_XPRINTF_H_
+
+#include <bfdev/config.h>
+#include <bfdev/types.h>
+#include <bfdev/stddef.h>
+#include <bfdev/stdarg.h>
+
+BFDEV_BEGIN_DECLS
+
+typedef struct bfdev_vxprintf bfdev_vxprintf_t;
+
+typedef void
+(*bfdev_vxprintf_write)(const char *buff, bfdev_size_t len, void *pdata);
+
+struct bfdev_vxprintf {
+    bfdev_vxprintf_write write;
+    void *pdata;
+};
+
+extern __bfdev_printf(2, 0) bfdev_size_t
+bfdev_vxfprintf(bfdev_vxprintf_t *ctx, const char *fmt, bfdev_va_list args);
+
+extern __bfdev_printf(2, 3) bfdev_size_t
+bfdev_xfprintf(bfdev_vxprintf_t *ctx, const char *fmt, ...);
+
+extern __bfdev_printf(3, 0) bfdev_size_t
+bfdev_xnprintf(char *buff, bfdev_size_t size, const char *fmt, bfdev_va_list args);
+
+extern __bfdev_printf(3, 4) bfdev_size_t
+bfdev_xprintf(char *buff, bfdev_size_t size, const char *fmt, ...);
+
+BFDEV_END_DECLS
+
+#endif /* _BFDEV_XPRINTF_H_ */

port/generic/stdio.c

@@ -3,6 +3,7 @@
  * Copyright(c) 2025 John Sanpe <sanpeqf@gmail.com>
  */
 
+#include <bfdev/xprintf.h>
 #include <port/stdio.h>
 #include <export.h>
 
@@ -12,5 +13,5 @@ __bfdev_weak int
 bfport_vsnprintf(char *s, bfdev_size_t maxlen, const char *fmt,
                  bfdev_va_list arg)
 {
-    return 0;
+    return bfdev_xnprintf(s, maxlen, fmt, arg);
 }

src/libc/build.cmake

@@ -8,4 +8,6 @@ set(BFDEV_SOURCE
     ${CMAKE_CURRENT_LIST_DIR}/ctype.c
     ${CMAKE_CURRENT_LIST_DIR}/strdup.c
     ${CMAKE_CURRENT_LIST_DIR}/string.c
+    ${CMAKE_CURRENT_LIST_DIR}/xfprintf.c
+    ${CMAKE_CURRENT_LIST_DIR}/xprintf.c
 )