efi/libstub: Add a basic printf implementation (2c7d1e30) · Commits · EulixOS / Software / Kernel

drivers/firmware/efi/libstub/Makefile

+1 −1

Original line number	Diff line number	Diff line
		@@ -44,7 +44,7 @@ KCOV_INSTRUMENT := n
		lib-y := efi-stub-helper.o gop.o secureboot.o tpm.o \
		file.o mem.o random.o randomalloc.o pci.o \
		skip_spaces.o lib-cmdline.o lib-ctype.o \
		alignedmem.o relocate.o
		alignedmem.o relocate.o vsprintf.o

		# include the stub's generic dependencies from lib/ when building for ARM/arm64
		efi-deps-y := fdt_rw.c fdt_ro.c fdt_wip.c fdt.c fdt_empty_tree.c fdt_sw.c

drivers/firmware/efi/libstub/efi-stub-helper.c

+17 −0

Original line number	Diff line number	Diff line
		@@ -7,6 +7,8 @@
		* Copyright 2011 Intel Corporation; author Matt Fleming
		*/

		#include <stdarg.h>

		#include <linux/efi.h>
		#include <linux/kernel.h>
		#include <asm/efi.h>
		@@ -51,6 +53,21 @@ void efi_puts(const char *str)
		}
		}

		int efi_printk(const char *fmt, ...)
		{
		char printf_buf[256];
		va_list args;
		int printed;

		va_start(args, fmt);
		printed = vsprintf(printf_buf, fmt, args);
		va_end(args);

		efi_puts(printf_buf);

		return printed;
		}

		/*
		* Parse the ASCII string 'cmdline' for EFI options, denoted by the efi=
		* option, e.g. efi=nochunk.

drivers/firmware/efi/libstub/efistub.h

+3 −0

Original line number	Diff line number	Diff line
		@@ -3,6 +3,7 @@
		#ifndef _DRIVERS_FIRMWARE_EFI_EFISTUB_H
		#define _DRIVERS_FIRMWARE_EFI_EFISTUB_H

		#include <linux/compiler.h>
		#include <linux/efi.h>
		#include <linux/kernel.h>
		#include <linux/types.h>
		@@ -632,6 +633,8 @@ void *get_efi_config_table(efi_guid_t guid);
		void efi_char16_puts(efi_char16_t *);
		void efi_puts(const char *str);

		__printf(1, 2) int efi_printk(char const *fmt, ...);

		void efi_free(unsigned long size, unsigned long addr);

		char efi_convert_cmdline(efi_loaded_image_t image, int *cmd_line_len,

drivers/firmware/efi/libstub/vsprintf.c

0 → 100644

+299 −0

Original line number	Diff line number	Diff line
		// SPDX-License-Identifier: GPL-2.0-only
		/* -- linux-c -- ------------------------------------------------------- *
		*
		* Copyright (C) 1991, 1992 Linus Torvalds
		* Copyright 2007 rPath, Inc. - All Rights Reserved
		*
		* ----------------------------------------------------------------------- */

		/*
		* Oh, it's a waste of space, but oh-so-yummy for debugging. This
		* version of printf() does not include 64-bit support. "Live with
		* it."
		*
		*/

		#include <stdarg.h>

		#include <linux/compiler.h>
		#include <linux/ctype.h>
		#include <linux/string.h>

		static int skip_atoi(const char **s)
		{
		int i = 0;

		while (isdigit(**s))
		i = i * 10 + ((s)++) - '0';
		return i;
		}

		#define ZEROPAD 1 /* pad with zero */
		#define SIGN 2 /* unsigned/signed long */
		#define PLUS 4 /* show plus */
		#define SPACE 8 /* space if plus */
		#define LEFT 16 /* left justified */
		#define SMALL 32 /* Must be 32 == 0x20 */
		#define SPECIAL 64 /* 0x */

		#define __do_div(n, base) ({ \
		int __res; \
		__res = ((unsigned long) n) % (unsigned) base; \
		n = ((unsigned long) n) / (unsigned) base; \
		__res; })

		static char number(char str, long num, int base, int size, int precision,
		int type)
		{
		/* we are called with base 8, 10 or 16, only, thus don't need "G..." */
		static const char digits[16] = "0123456789ABCDEF"; /* "GHIJKLMNOPQRSTUVWXYZ"; */

		char tmp[66];
		char c, sign, locase;
		int i;

		/* locase = 0 or 0x20. ORing digits or letters with 'locase'
		* produces same digits or (maybe lowercased) letters */
		locase = (type & SMALL);
		if (type & LEFT)
		type &= ~ZEROPAD;
		if (base < 2 \|\| base > 16)
		return NULL;
		c = (type & ZEROPAD) ? '0' : ' ';
		sign = 0;
		if (type & SIGN) {
		if (num < 0) {
		sign = '-';
		num = -num;
		size--;
		} else if (type & PLUS) {
		sign = '+';
		size--;
		} else if (type & SPACE) {
		sign = ' ';
		size--;
		}
		}
		if (type & SPECIAL) {
		if (base == 16)
		size -= 2;
		else if (base == 8)
		size--;
		}
		i = 0;
		if (num == 0)
		tmp[i++] = '0';
		else
		while (num != 0)
		tmp[i++] = (digits[__do_div(num, base)] \| locase);
		if (i > precision)
		precision = i;
		size -= precision;
		if (!(type & (ZEROPAD + LEFT)))
		while (size-- > 0)
		*str++ = ' ';
		if (sign)
		*str++ = sign;
		if (type & SPECIAL) {
		if (base == 8) {
		*str++ = '0';
		} else if (base == 16) {
		*str++ = '0';
		*str++ = ('X' \| locase);
		}
		}
		if (!(type & LEFT))
		while (size-- > 0)
		*str++ = c;
		while (i < precision--)
		*str++ = '0';
		while (i-- > 0)
		*str++ = tmp[i];
		while (size-- > 0)
		*str++ = ' ';
		return str;
		}

		int vsprintf(char buf, const char fmt, va_list args)
		{
		int len;
		unsigned long num;
		int i, base;
		char *str;
		const char *s;

		int flags; /* flags to number() */

		int field_width; /* width of output field */
		int precision; /* min. # of digits for integers; max
		number of chars for from string */
		int qualifier; /* 'h', 'l', or 'L' for integer fields */

		for (str = buf; *fmt; ++fmt) {
		if (*fmt != '%') {
		str++ = fmt;
		continue;
		}

		/* process flags */
		flags = 0;
		repeat:
		++fmt; /* this also skips first '%' */
		switch (*fmt) {
		case '-':
		flags \|= LEFT;
		goto repeat;
		case '+':
		flags \|= PLUS;
		goto repeat;
		case ' ':
		flags \|= SPACE;
		goto repeat;
		case '#':
		flags \|= SPECIAL;
		goto repeat;
		case '0':
		flags \|= ZEROPAD;
		goto repeat;
		}

		/* get field width */
		field_width = -1;
		if (isdigit(*fmt)) {
		field_width = skip_atoi(&fmt);
		} else if (fmt == '') {
		++fmt;
		/* it's the next argument */
		field_width = va_arg(args, int);
		if (field_width < 0) {
		field_width = -field_width;
		flags \|= LEFT;
		}
		}

		/* get the precision */
		precision = -1;
		if (*fmt == '.') {
		++fmt;
		if (isdigit(*fmt)) {
		precision = skip_atoi(&fmt);
		} else if (fmt == '') {
		++fmt;
		/* it's the next argument */
		precision = va_arg(args, int);
		}
		if (precision < 0)
		precision = 0;
		}

		/* get the conversion qualifier */
		qualifier = -1;
		if (fmt == 'h' \|\| fmt == 'l' \|\| *fmt == 'L') {
		qualifier = *fmt;
		++fmt;
		}

		/* default base */
		base = 10;

		switch (*fmt) {
		case 'c':
		if (!(flags & LEFT))
		while (--field_width > 0)
		*str++ = ' ';
		*str++ = (unsigned char)va_arg(args, int);
		while (--field_width > 0)
		*str++ = ' ';
		continue;

		case 's':
		s = va_arg(args, char *);
		len = strnlen(s, precision);

		if (!(flags & LEFT))
		while (len < field_width--)
		*str++ = ' ';
		for (i = 0; i < len; ++i)
		str++ = s++;
		while (len < field_width--)
		*str++ = ' ';
		continue;

		case 'p':
		if (field_width == -1) {
		field_width = 2 * sizeof(void *);
		flags \|= ZEROPAD;
		}
		str = number(str,
		(unsigned long)va_arg(args, void *), 16,
		field_width, precision, flags);
		continue;

		case 'n':
		if (qualifier == 'l') {
		long ip = va_arg(args, long );
		*ip = (str - buf);
		} else {
		int ip = va_arg(args, int );
		*ip = (str - buf);
		}
		continue;

		case '%':
		*str++ = '%';
		continue;

		/* integer number formats - set up the flags and "break" */
		case 'o':
		base = 8;
		break;

		case 'x':
		flags \|= SMALL;
		fallthrough;
		case 'X':
		base = 16;
		break;

		case 'd':
		case 'i':
		flags \|= SIGN;
		fallthrough;
		case 'u':
		break;

		default:
		*str++ = '%';
		if (*fmt)
		str++ = fmt;
		else
		--fmt;
		continue;
		}
		if (qualifier == 'l') {
		num = va_arg(args, unsigned long);
		} else if (qualifier == 'h') {
		num = (unsigned short)va_arg(args, int);
		if (flags & SIGN)
		num = (short)num;
		} else if (flags & SIGN) {
		num = va_arg(args, int);
		} else {
		num = va_arg(args, unsigned int);
		}
		str = number(str, num, base, field_width, precision, flags);
		}
		*str = '\0';
		return str - buf;
		}

		int sprintf(char buf, const char fmt, ...)
		{
		va_list args;
		int i;

		va_start(args, fmt);
		i = vsprintf(buf, fmt, args);
		va_end(args);
		return i;
		}