From af7f4165512ea242b5f711ee03a04f6afe22232d Mon Sep 17 00:00:00 2001 From: Florian Weimer Date: Mon, 19 Dec 2022 18:56:55 +0100 Subject: libio: Convert __vasprintf_internal to buffers The buffer resizing algorithm is slightly different. The initial buffer is on the stack, and small buffers are directly allocated on the heap using the exact required size. The overhead of the additional copy is compensated by the lowered setup cost for buffers compared to libio streams. Reviewed-by: Adhemerval Zanella --- include/printf_buffer.h | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'include') diff --git a/include/printf_buffer.h b/include/printf_buffer.h index cc9f8e5346..c8e22e1e90 100644 --- a/include/printf_buffer.h +++ b/include/printf_buffer.h @@ -49,6 +49,7 @@ enum __printf_buffer_mode __printf_buffer_mode_snprintf, __printf_buffer_mode_sprintf_chk, __printf_buffer_mode_to_file, + __printf_buffer_mode_asprintf, __printf_buffer_mode_strfmon, __printf_buffer_mode_fp, /* For __printf_fp_l_buffer. */ __printf_buffer_mode_fp_to_wide, /* For __wprintf_fp_l_buffer. */ @@ -304,6 +305,9 @@ void __printf_buffer_flush_snprintf (struct __printf_buffer_snprintf *) struct __printf_buffer_to_file; void __printf_buffer_flush_to_file (struct __printf_buffer_to_file *) attribute_hidden; +struct __printf_buffer_asprintf; +void __printf_buffer_flush_asprintf (struct __printf_buffer_asprintf *) + attribute_hidden; struct __printf_buffer_fp; void __printf_buffer_flush_fp (struct __printf_buffer_fp *) attribute_hidden; @@ -332,4 +336,9 @@ void __wprintf_buffer_flush_to_file (struct __wprintf_buffer_to_file *) /* Temporary buffer used during floating point digit translation. */ #define PRINTF_BUFFER_SIZE_DIGITS 64 +/* Size of the initial on-stack buffer for asprintf. It should be + large enough to copy almost all asprintf usages with just a single + (final, correctly sized) heap allocation. */ +#define PRINTF_BUFFER_SIZE_ASPRINTF 200 + #endif /* PRINTF_BUFFER_H */ -- cgit 1.4.1