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Diffstat (limited to 'drivers/firmware/efi/libstub/vsprintf.c')
-rw-r--r--drivers/firmware/efi/libstub/vsprintf.c564
1 files changed, 564 insertions, 0 deletions
diff --git a/drivers/firmware/efi/libstub/vsprintf.c b/drivers/firmware/efi/libstub/vsprintf.c
new file mode 100644
index 000000000..71c71c222
--- /dev/null
+++ b/drivers/firmware/efi/libstub/vsprintf.c
@@ -0,0 +1,564 @@
+// 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.
+ */
+
+#include <linux/stdarg.h>
+
+#include <linux/compiler.h>
+#include <linux/ctype.h>
+#include <linux/kernel.h>
+#include <linux/limits.h>
+#include <linux/string.h>
+#include <linux/types.h>
+
+static
+int skip_atoi(const char **s)
+{
+ int i = 0;
+
+ while (isdigit(**s))
+ i = i * 10 + *((*s)++) - '0';
+ return i;
+}
+
+/*
+ * put_dec_full4 handles numbers in the range 0 <= r < 10000.
+ * The multiplier 0xccd is round(2^15/10), and the approximation
+ * r/10 == (r * 0xccd) >> 15 is exact for all r < 16389.
+ */
+static
+void put_dec_full4(char *end, unsigned int r)
+{
+ int i;
+
+ for (i = 0; i < 3; i++) {
+ unsigned int q = (r * 0xccd) >> 15;
+ *--end = '0' + (r - q * 10);
+ r = q;
+ }
+ *--end = '0' + r;
+}
+
+/* put_dec is copied from lib/vsprintf.c with small modifications */
+
+/*
+ * Call put_dec_full4 on x % 10000, return x / 10000.
+ * The approximation x/10000 == (x * 0x346DC5D7) >> 43
+ * holds for all x < 1,128,869,999. The largest value this
+ * helper will ever be asked to convert is 1,125,520,955.
+ * (second call in the put_dec code, assuming n is all-ones).
+ */
+static
+unsigned int put_dec_helper4(char *end, unsigned int x)
+{
+ unsigned int q = (x * 0x346DC5D7ULL) >> 43;
+
+ put_dec_full4(end, x - q * 10000);
+ return q;
+}
+
+/* Based on code by Douglas W. Jones found at
+ * <http://www.cs.uiowa.edu/~jones/bcd/decimal.html#sixtyfour>
+ * (with permission from the author).
+ * Performs no 64-bit division and hence should be fast on 32-bit machines.
+ */
+static
+char *put_dec(char *end, unsigned long long n)
+{
+ unsigned int d3, d2, d1, q, h;
+ char *p = end;
+
+ d1 = ((unsigned int)n >> 16); /* implicit "& 0xffff" */
+ h = (n >> 32);
+ d2 = (h ) & 0xffff;
+ d3 = (h >> 16); /* implicit "& 0xffff" */
+
+ /* n = 2^48 d3 + 2^32 d2 + 2^16 d1 + d0
+ = 281_4749_7671_0656 d3 + 42_9496_7296 d2 + 6_5536 d1 + d0 */
+ q = 656 * d3 + 7296 * d2 + 5536 * d1 + ((unsigned int)n & 0xffff);
+ q = put_dec_helper4(p, q);
+ p -= 4;
+
+ q += 7671 * d3 + 9496 * d2 + 6 * d1;
+ q = put_dec_helper4(p, q);
+ p -= 4;
+
+ q += 4749 * d3 + 42 * d2;
+ q = put_dec_helper4(p, q);
+ p -= 4;
+
+ q += 281 * d3;
+ q = put_dec_helper4(p, q);
+ p -= 4;
+
+ put_dec_full4(p, q);
+ p -= 4;
+
+ /* strip off the extra 0's we printed */
+ while (p < end && *p == '0')
+ ++p;
+
+ return p;
+}
+
+static
+char *number(char *end, unsigned long long num, int base, char locase)
+{
+ /*
+ * locase = 0 or 0x20. ORing digits or letters with 'locase'
+ * produces same digits or (maybe lowercased) letters
+ */
+
+ /* we are called with base 8, 10 or 16, only, thus don't need "G..." */
+ static const char digits[16] = "0123456789ABCDEF"; /* "GHIJKLMNOPQRSTUVWXYZ"; */
+
+ switch (base) {
+ case 10:
+ if (num != 0)
+ end = put_dec(end, num);
+ break;
+ case 8:
+ for (; num != 0; num >>= 3)
+ *--end = '0' + (num & 07);
+ break;
+ case 16:
+ for (; num != 0; num >>= 4)
+ *--end = digits[num & 0xf] | locase;
+ break;
+ default:
+ unreachable();
+ }
+
+ return end;
+}
+
+#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 WIDE 128 /* UTF-16 string */
+
+static
+int get_flags(const char **fmt)
+{
+ int flags = 0;
+
+ do {
+ switch (**fmt) {
+ case '-':
+ flags |= LEFT;
+ break;
+ case '+':
+ flags |= PLUS;
+ break;
+ case ' ':
+ flags |= SPACE;
+ break;
+ case '#':
+ flags |= SPECIAL;
+ break;
+ case '0':
+ flags |= ZEROPAD;
+ break;
+ default:
+ return flags;
+ }
+ ++(*fmt);
+ } while (1);
+}
+
+static
+int get_int(const char **fmt, va_list *ap)
+{
+ if (isdigit(**fmt))
+ return skip_atoi(fmt);
+ if (**fmt == '*') {
+ ++(*fmt);
+ /* it's the next argument */
+ return va_arg(*ap, int);
+ }
+ return 0;
+}
+
+static
+unsigned long long get_number(int sign, int qualifier, va_list *ap)
+{
+ if (sign) {
+ switch (qualifier) {
+ case 'L':
+ return va_arg(*ap, long long);
+ case 'l':
+ return va_arg(*ap, long);
+ case 'h':
+ return (short)va_arg(*ap, int);
+ case 'H':
+ return (signed char)va_arg(*ap, int);
+ default:
+ return va_arg(*ap, int);
+ };
+ } else {
+ switch (qualifier) {
+ case 'L':
+ return va_arg(*ap, unsigned long long);
+ case 'l':
+ return va_arg(*ap, unsigned long);
+ case 'h':
+ return (unsigned short)va_arg(*ap, int);
+ case 'H':
+ return (unsigned char)va_arg(*ap, int);
+ default:
+ return va_arg(*ap, unsigned int);
+ }
+ }
+}
+
+static
+char get_sign(long long *num, int flags)
+{
+ if (!(flags & SIGN))
+ return 0;
+ if (*num < 0) {
+ *num = -(*num);
+ return '-';
+ }
+ if (flags & PLUS)
+ return '+';
+ if (flags & SPACE)
+ return ' ';
+ return 0;
+}
+
+static
+size_t utf16s_utf8nlen(const u16 *s16, size_t maxlen)
+{
+ size_t len, clen;
+
+ for (len = 0; len < maxlen && *s16; len += clen) {
+ u16 c0 = *s16++;
+
+ /* First, get the length for a BMP character */
+ clen = 1 + (c0 >= 0x80) + (c0 >= 0x800);
+ if (len + clen > maxlen)
+ break;
+ /*
+ * If this is a high surrogate, and we're already at maxlen, we
+ * can't include the character if it's a valid surrogate pair.
+ * Avoid accessing one extra word just to check if it's valid
+ * or not.
+ */
+ if ((c0 & 0xfc00) == 0xd800) {
+ if (len + clen == maxlen)
+ break;
+ if ((*s16 & 0xfc00) == 0xdc00) {
+ ++s16;
+ ++clen;
+ }
+ }
+ }
+
+ return len;
+}
+
+static
+u32 utf16_to_utf32(const u16 **s16)
+{
+ u16 c0, c1;
+
+ c0 = *(*s16)++;
+ /* not a surrogate */
+ if ((c0 & 0xf800) != 0xd800)
+ return c0;
+ /* invalid: low surrogate instead of high */
+ if (c0 & 0x0400)
+ return 0xfffd;
+ c1 = **s16;
+ /* invalid: missing low surrogate */
+ if ((c1 & 0xfc00) != 0xdc00)
+ return 0xfffd;
+ /* valid surrogate pair */
+ ++(*s16);
+ return (0x10000 - (0xd800 << 10) - 0xdc00) + (c0 << 10) + c1;
+}
+
+#define PUTC(c) \
+do { \
+ if (pos < size) \
+ buf[pos] = (c); \
+ ++pos; \
+} while (0);
+
+int vsnprintf(char *buf, size_t size, const char *fmt, va_list ap)
+{
+ /* The maximum space required is to print a 64-bit number in octal */
+ char tmp[(sizeof(unsigned long long) * 8 + 2) / 3];
+ char *tmp_end = &tmp[ARRAY_SIZE(tmp)];
+ long long num;
+ int base;
+ const char *s;
+ size_t len, pos;
+ char sign;
+
+ 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', 'hh', 'l' or 'll' for integer fields */
+
+ va_list args;
+
+ /*
+ * We want to pass our input va_list to helper functions by reference,
+ * but there's an annoying edge case. If va_list was originally passed
+ * to us by value, we could just pass &ap down to the helpers. This is
+ * the case on, for example, X86_32.
+ * However, on X86_64 (and possibly others), va_list is actually a
+ * size-1 array containing a structure. Our function parameter ap has
+ * decayed from T[1] to T*, and &ap has type T** rather than T(*)[1],
+ * which is what will be expected by a function taking a va_list *
+ * parameter.
+ * One standard way to solve this mess is by creating a copy in a local
+ * variable of type va_list and then passing a pointer to that local
+ * copy instead, which is what we do here.
+ */
+ va_copy(args, ap);
+
+ for (pos = 0; *fmt; ++fmt) {
+ if (*fmt != '%' || *++fmt == '%') {
+ PUTC(*fmt);
+ continue;
+ }
+
+ /* process flags */
+ flags = get_flags(&fmt);
+
+ /* get field width */
+ field_width = get_int(&fmt, &args);
+ if (field_width < 0) {
+ field_width = -field_width;
+ flags |= LEFT;
+ }
+
+ if (flags & LEFT)
+ flags &= ~ZEROPAD;
+
+ /* get the precision */
+ precision = -1;
+ if (*fmt == '.') {
+ ++fmt;
+ precision = get_int(&fmt, &args);
+ if (precision >= 0)
+ flags &= ~ZEROPAD;
+ }
+
+ /* get the conversion qualifier */
+ qualifier = -1;
+ if (*fmt == 'h' || *fmt == 'l') {
+ qualifier = *fmt;
+ ++fmt;
+ if (qualifier == *fmt) {
+ qualifier -= 'a'-'A';
+ ++fmt;
+ }
+ }
+
+ sign = 0;
+
+ switch (*fmt) {
+ case 'c':
+ flags &= LEFT;
+ s = tmp;
+ if (qualifier == 'l') {
+ ((u16 *)tmp)[0] = (u16)va_arg(args, unsigned int);
+ ((u16 *)tmp)[1] = L'\0';
+ precision = INT_MAX;
+ goto wstring;
+ } else {
+ tmp[0] = (unsigned char)va_arg(args, int);
+ precision = len = 1;
+ }
+ goto output;
+
+ case 's':
+ flags &= LEFT;
+ if (precision < 0)
+ precision = INT_MAX;
+ s = va_arg(args, void *);
+ if (!s)
+ s = precision < 6 ? "" : "(null)";
+ else if (qualifier == 'l') {
+ wstring:
+ flags |= WIDE;
+ precision = len = utf16s_utf8nlen((const u16 *)s, precision);
+ goto output;
+ }
+ precision = len = strnlen(s, precision);
+ goto output;
+
+ /* integer number formats - set up the flags and "break" */
+ case 'o':
+ base = 8;
+ break;
+
+ case 'p':
+ if (precision < 0)
+ precision = 2 * sizeof(void *);
+ fallthrough;
+ case 'x':
+ flags |= SMALL;
+ fallthrough;
+ case 'X':
+ base = 16;
+ break;
+
+ case 'd':
+ case 'i':
+ flags |= SIGN;
+ fallthrough;
+ case 'u':
+ flags &= ~SPECIAL;
+ base = 10;
+ break;
+
+ default:
+ /*
+ * Bail out if the conversion specifier is invalid.
+ * There's probably a typo in the format string and the
+ * remaining specifiers are unlikely to match up with
+ * the arguments.
+ */
+ goto fail;
+ }
+ if (*fmt == 'p') {
+ num = (unsigned long)va_arg(args, void *);
+ } else {
+ num = get_number(flags & SIGN, qualifier, &args);
+ }
+
+ sign = get_sign(&num, flags);
+ if (sign)
+ --field_width;
+
+ s = number(tmp_end, num, base, flags & SMALL);
+ len = tmp_end - s;
+ /* default precision is 1 */
+ if (precision < 0)
+ precision = 1;
+ /* precision is minimum number of digits to print */
+ if (precision < len)
+ precision = len;
+ if (flags & SPECIAL) {
+ /*
+ * For octal, a leading 0 is printed only if necessary,
+ * i.e. if it's not already there because of the
+ * precision.
+ */
+ if (base == 8 && precision == len)
+ ++precision;
+ /*
+ * For hexadecimal, the leading 0x is skipped if the
+ * output is empty, i.e. both the number and the
+ * precision are 0.
+ */
+ if (base == 16 && precision > 0)
+ field_width -= 2;
+ else
+ flags &= ~SPECIAL;
+ }
+ /*
+ * For zero padding, increase the precision to fill the field
+ * width.
+ */
+ if ((flags & ZEROPAD) && field_width > precision)
+ precision = field_width;
+
+output:
+ /* Calculate the padding necessary */
+ field_width -= precision;
+ /* Leading padding with ' ' */
+ if (!(flags & LEFT))
+ while (field_width-- > 0)
+ PUTC(' ');
+ /* sign */
+ if (sign)
+ PUTC(sign);
+ /* 0x/0X for hexadecimal */
+ if (flags & SPECIAL) {
+ PUTC('0');
+ PUTC( 'X' | (flags & SMALL));
+ }
+ /* Zero padding and excess precision */
+ while (precision-- > len)
+ PUTC('0');
+ /* Actual output */
+ if (flags & WIDE) {
+ const u16 *ws = (const u16 *)s;
+
+ while (len-- > 0) {
+ u32 c32 = utf16_to_utf32(&ws);
+ u8 *s8;
+ size_t clen;
+
+ if (c32 < 0x80) {
+ PUTC(c32);
+ continue;
+ }
+
+ /* Number of trailing octets */
+ clen = 1 + (c32 >= 0x800) + (c32 >= 0x10000);
+
+ len -= clen;
+ s8 = (u8 *)&buf[pos];
+
+ /* Avoid writing partial character */
+ PUTC('\0');
+ pos += clen;
+ if (pos >= size)
+ continue;
+
+ /* Set high bits of leading octet */
+ *s8 = (0xf00 >> 1) >> clen;
+ /* Write trailing octets in reverse order */
+ for (s8 += clen; clen; --clen, c32 >>= 6)
+ *s8-- = 0x80 | (c32 & 0x3f);
+ /* Set low bits of leading octet */
+ *s8 |= c32;
+ }
+ } else {
+ while (len-- > 0)
+ PUTC(*s++);
+ }
+ /* Trailing padding with ' ' */
+ while (field_width-- > 0)
+ PUTC(' ');
+ }
+fail:
+ va_end(args);
+
+ if (size)
+ buf[min(pos, size-1)] = '\0';
+
+ return pos;
+}
+
+int snprintf(char *buf, size_t size, const char *fmt, ...)
+{
+ va_list args;
+ int i;
+
+ va_start(args, fmt);
+ i = vsnprintf(buf, size, fmt, args);
+ va_end(args);
+ return i;
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-01 06:49:36 +0000