From 659fe9fdd14b0772f4e9722b751b9b010665e053 Mon Sep 17 00:00:00 2001 From: Florian Weimer Date: Mon, 19 Dec 2022 18:56:54 +0100 Subject: stdio-common: Introduce buffers for implementing printf These buffers will eventually be used instead of FILE * objects to implement printf functions. The multibyte buffer is struct __printf_buffer, the wide buffer is struct __wprintf_buffer. To enable writing type-generic code, the header files printf_buffer-char.h and printf_buffer-wchar_t.h define the Xprintf macro differently, enabling Xprintf (buffer) to stand for __printf_buffer and __wprintf_buffer as appropriate. For common cases, macros like Xprintf_buffer are provided as a more syntactically convenient shortcut. Buffer-specific flush callbacks are implemented with a switch statement instead of a function pointer, to avoid hardening issues similar to those of libio vtables. struct __printf_buffer_as_file is needed to support custom printf specifiers because the public interface for that requires passing a FILE *, which is why there is a trapdoor back from these buffers to FILE * streams. Since the immediate user of these interfaces knows when processing has finished, there is no flush callback for the end of processing, only a flush callback for the intermediate buffer flush. Reviewed-by: Adhemerval Zanella --- stdio-common/Makefile | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) (limited to 'stdio-common/Makefile') diff --git a/stdio-common/Makefile b/stdio-common/Makefile index 8f2524959d..120d66ea93 100644 --- a/stdio-common/Makefile +++ b/stdio-common/Makefile @@ -53,6 +53,14 @@ routines := \ perror \ printf \ printf-prs \ + printf_buffer_as_file \ + printf_buffer_done \ + printf_buffer_flush \ + printf_buffer_pad_1 \ + printf_buffer_putc_1 \ + printf_buffer_puts_1 \ + printf_buffer_to_file \ + printf_buffer_write \ printf_fp \ printf_fphex \ printf_size \ @@ -85,6 +93,14 @@ routines := \ vfwscanf \ vfwscanf-internal \ vprintf \ + wprintf_buffer_as_file \ + wprintf_buffer_done \ + wprintf_buffer_flush \ + wprintf_buffer_pad_1 \ + wprintf_buffer_putc_1 \ + wprintf_buffer_puts_1 \ + wprintf_buffer_to_file \ + wprintf_buffer_write \ # routines aux := \ -- cgit v1.2.3