diff options
author | Andrii Anisov <andrii_anisov@epam.com> | 2020-08-06 12:42:52 +0300 |
---|---|---|
committer | Tom Rini <trini@konsulko.com> | 2020-08-14 15:18:30 -0400 |
commit | e87dfb0526be231de89b299531a0e637d343fccd (patch) | |
tree | 22321a741fed68f97ffc74287bc00660c7f5d39e /lib | |
parent | 242587dca4a7e34023b4c87d5b52a74b2fe7255d (diff) |
lib: sscanf: add sscanf implementation
Port sscanf implementation from mini-os and introduce new
Kconfig option to enable it: CONFIG_SSCANF. Disable by default.
Signed-off-by: Andrii Anisov <andrii_anisov@epam.com>
Signed-off-by: Anastasiia Lukianenko <anastasiia_lukianenko@epam.com>
Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Diffstat (limited to 'lib')
-rw-r--r-- | lib/Kconfig | 4 | ||||
-rw-r--r-- | lib/Makefile | 1 | ||||
-rw-r--r-- | lib/sscanf.c | 823 |
3 files changed, 828 insertions, 0 deletions
diff --git a/lib/Kconfig b/lib/Kconfig index 089348af73..8efb154f73 100644 --- a/lib/Kconfig +++ b/lib/Kconfig @@ -80,6 +80,10 @@ config SPL_SPRINTF config TPL_SPRINTF bool +config SSCANF + bool + default n + config STRTO bool default y diff --git a/lib/Makefile b/lib/Makefile index 1dc06c57d5..0cd7bea282 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -123,6 +123,7 @@ else # Main U-Boot always uses the full printf support obj-y += vsprintf.o strto.o obj-$(CONFIG_OID_REGISTRY) += oid_registry.o +obj-$(CONFIG_SSCANF) += sscanf.o endif obj-y += date.o diff --git a/lib/sscanf.c b/lib/sscanf.c new file mode 100644 index 0000000000..d1e2dc272c --- /dev/null +++ b/lib/sscanf.c @@ -0,0 +1,823 @@ +// SPDX-License-Identifier: BSD-3-Clause +/* + * Copyright (c) 1990, 1993 + * The Regents of the University of California. All rights reserved. + * + * This code is derived from software contributed to Berkeley by + * Chris Torek. + * + * Copyright (c) 2011 The FreeBSD Foundation + * All rights reserved. + * Portions of this software were developed by David Chisnall + * under sponsorship from the FreeBSD Foundation. + * + * Author: Juergen Gross <jgross@suse.com> + * Date: Jun 2016 + */ + +#if !defined HAVE_LIBC + +#include <os.h> +#include <linux/kernel.h> +#include <linux/ctype.h> +#include <vsprintf.h> +#include <linux/string.h> +#include <malloc.h> +#define __DECONST(type, var) ((type)(uintptr_t)(const void *)(var)) + +/** + * struct str_info - Input string parameters + * @neg: negative number or not + * 0 - not negative + * 1 - negative + * @any: set any if any `digits' consumed; make it negative to indicate + * overflow + * @acc: accumulated value + */ +struct str_info { + int neg, any; + u64 acc; +}; + +/** + * str_to_int_convert() - Write string data to structure + * @nptr: pointer to string + * @base: number's base + * @unsign: describes what integer is expected + * 0 - not unsigned + * 1 - unsigned + * + * Ignores `locale' stuff. Assumes that the upper and lower case + * alphabets and digits are each contiguous. + * + * Return: struct str_info *, which contains string data to future process + */ +static struct str_info * +str_to_int_convert(const char **nptr, int base, unsigned int unsign) +{ + const char *s = *nptr; + u64 acc; + unsigned char c; + u64 cutoff; + int neg, any, cutlim; + u64 qbase; + struct str_info *info; + + /* + * Skip white space and pick up leading +/- sign if any. + * If base is 0, allow 0x for hex and 0 for octal, else + * assume decimal; if base is already 16, allow 0x. + */ + info = (struct str_info *)malloc(sizeof(struct str_info)); + if (!info) + return NULL; + + do { + c = *s++; + } while (isspace(c)); + if (c == '-') { + neg = 1; + c = *s++; + } else { + neg = 0; + if (c == '+') + c = *s++; + } + if ((base == 0 || base == 16) && + c == '0' && (*s == 'x' || *s == 'X')) { + c = s[1]; + s += 2; + base = 16; + } + if (base == 0) + base = c == '0' ? 8 : 10; + + /* + * Compute the cutoff value between legal numbers and illegal + * numbers. That is the largest legal value, divided by the + * base. An input number that is greater than this value, if + * followed by a legal input character, is too big. One that + * is equal to this value may be valid or not; the limit + * between valid and invalid numbers is then based on the last + * digit. For instance, if the range for quads is + * [-9223372036854775808..9223372036854775807] and the input base + * is 10, cutoff will be set to 922337203685477580 and cutlim to + * either 7 (neg==0) or 8 (neg==1), meaning that if we have + * accumulated a value > 922337203685477580, or equal but the + * next digit is > 7 (or 8), the number is too big, and we will + * return a range error. + * + * Set any if any `digits' consumed; make it negative to indicate + * overflow. + */ + qbase = (unsigned int)base; + + if (!unsign) { + cutoff = neg ? (u64)-(LLONG_MIN + LLONG_MAX) + LLONG_MAX : LLONG_MAX; + cutlim = cutoff % qbase; + cutoff /= qbase; + } else { + cutoff = (u64)ULLONG_MAX / qbase; + cutlim = (u64)ULLONG_MAX % qbase; + } + + for (acc = 0, any = 0;; c = *s++) { + if (!isascii(c)) + break; + if (isdigit(c)) + c -= '0'; + else if (isalpha(c)) + c -= isupper(c) ? 'A' - 10 : 'a' - 10; + else + break; + if (c >= base) + break; + if (any < 0 || acc > cutoff || (acc == cutoff && c > cutlim)) { + any = -1; + } else { + any = 1; + acc *= qbase; + acc += c; + } + } + + info->any = any; + info->neg = neg; + info->acc = acc; + + *nptr = s; + + return info; +} + +/** + * strtoq() - Convert a string to a quad integer + * @nptr: pointer to string + * @endptr: pointer to number's end in the string + * @base: number's base + * + * Return: s64 quad integer number converted from input string + */ +static s64 +strtoq(const char *nptr, char **endptr, int base) +{ + const char *s = nptr; + u64 acc; + int unsign = 0; + struct str_info *info; + + info = str_to_int_convert(&s, base, unsign); + if (!info) + return -1; + + acc = info->acc; + + if (info->any < 0) + acc = info->neg ? LLONG_MIN : LLONG_MAX; + else if (info->neg) + acc = -acc; + if (endptr != 0) + *endptr = __DECONST(char *, info->any ? s - 1 : nptr); + + free(info); + + return acc; +} + +/** + * strtouq() - Convert a string to an unsigned quad integer + * @nptr: pointer to string + * @endptr: pointer to number's end in the string + * @base: number's base + * + * Return: s64 unsigned quad integer number converted from + * input string + */ +u64 +strtouq(const char *nptr, char **endptr, int base) +{ + const char *s = nptr; + u64 acc; + int unsign = 1; + struct str_info *info; + + info = str_to_int_convert(&s, base, unsign); + if (!info) + return -1; + + acc = info->acc; + + if (info->any < 0) + acc = ULLONG_MAX; + else if (info->neg) + acc = -acc; + if (endptr != 0) + *endptr = __DECONST(char *, info->any ? s - 1 : nptr); + + free(info); + + return acc; +} + +/** + * __sccl() - Fill in the given table from the scanset at the given format + * (just after `[') + * @tab: table to fill in + * @fmt: format of buffer + * + * The table has a 1 wherever characters should be considered part of the + * scanset. + * + * Return: pointer to the character past the closing `]' + */ +static const u_char * +__sccl(char *tab, const u_char *fmt) +{ + int c, n, v; + + /* first `clear' the whole table */ + c = *fmt++; /* first char hat => negated scanset */ + if (c == '^') { + v = 1; /* default => accept */ + c = *fmt++; /* get new first char */ + } else { + v = 0; /* default => reject */ + } + + /* XXX: Will not work if sizeof(tab*) > sizeof(char) */ + for (n = 0; n < 256; n++) + tab[n] = v; /* memset(tab, v, 256) */ + + if (c == 0) + return (fmt - 1);/* format ended before closing ] */ + + /* + * Now set the entries corresponding to the actual scanset + * to the opposite of the above. + * + * The first character may be ']' (or '-') without being special; + * the last character may be '-'. + */ + v = 1 - v; + for (;;) { + tab[c] = v; /* take character c */ +doswitch: + n = *fmt++; /* and examine the next */ + switch (n) { + case 0: /* format ended too soon */ + return (fmt - 1); + + case '-': + /* + * A scanset of the form + * [01+-] + * is defined as `the digit 0, the digit 1, + * the character +, the character -', but + * the effect of a scanset such as + * [a-zA-Z0-9] + * is implementation defined. The V7 Unix + * scanf treats `a-z' as `the letters a through + * z', but treats `a-a' as `the letter a, the + * character -, and the letter a'. + * + * For compatibility, the `-' is not considerd + * to define a range if the character following + * it is either a close bracket (required by ANSI) + * or is not numerically greater than the character + * we just stored in the table (c). + */ + n = *fmt; + if (n == ']' || n < c) { + c = '-'; + break; /* resume the for(;;) */ + } + fmt++; + /* fill in the range */ + do { + tab[++c] = v; + } while (c < n); + c = n; + /* + * Alas, the V7 Unix scanf also treats formats + * such as [a-c-e] as `the letters a through e'. + * This too is permitted by the standard.... + */ + goto doswitch; + break; + + case ']': /* end of scanset */ + return (fmt); + + default: /* just another character */ + c = n; + break; + } + } + /* NOTREACHED */ +} + +/** + * vsscanf - Unformat a buffer into a list of arguments + * @buf: input buffer + * @fmt: format of buffer + * @args: arguments + */ +#define BUF 32 /* Maximum length of numeric string. */ + +/* + * Flags used during conversion. + */ +#define LONG 0x01 /* l: long or double */ +#define SHORT 0x04 /* h: short */ +#define SUPPRESS 0x08 /* suppress assignment */ +#define POINTER 0x10 /* weird %p pointer (`fake hex') */ +#define NOSKIP 0x20 /* do not skip blanks */ +#define QUAD 0x400 +#define SHORTSHORT 0x4000 /** hh: char */ + +/* + * The following are used in numeric conversions only: + * SIGNOK, NDIGITS, DPTOK, and EXPOK are for floating point; + * SIGNOK, NDIGITS, PFXOK, and NZDIGITS are for integral. + */ +#define SIGNOK 0x40 /* +/- is (still) legal */ +#define NDIGITS 0x80 /* no digits detected */ + +#define DPTOK 0x100 /* (float) decimal point is still legal */ +#define EXPOK 0x200 /* (float) exponent (e+3, etc) still legal */ + +#define PFXOK 0x100 /* 0x prefix is (still) legal */ +#define NZDIGITS 0x200 /* no zero digits detected */ + +/* + * Conversion types. + */ +#define CT_CHAR 0 /* %c conversion */ +#define CT_CCL 1 /* %[...] conversion */ +#define CT_STRING 2 /* %s conversion */ +#define CT_INT 3 /* integer, i.e., strtoq or strtouq */ +typedef u64 (*ccfntype)(const char *, char **, int); + +int +vsscanf(const char *inp, char const *fmt0, va_list ap) +{ + int inr; + const u_char *fmt = (const u_char *)fmt0; + int c; /* character from format, or conversion */ + size_t width; /* field width, or 0 */ + char *p; /* points into all kinds of strings */ + int n; /* handy integer */ + int flags; /* flags as defined above */ + char *p0; /* saves original value of p when necessary */ + int nassigned; /* number of fields assigned */ + int nconversions; /* number of conversions */ + int nread; /* number of characters consumed from fp */ + int base; /* base argument to strtoq/strtouq */ + ccfntype ccfn; /* conversion function (strtoq/strtouq) */ + char ccltab[256]; /* character class table for %[...] */ + char buf[BUF]; /* buffer for numeric conversions */ + + /* `basefix' is used to avoid `if' tests in the integer scanner */ + static short basefix[17] = { 10, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, + 12, 13, 14, 15, 16 }; + + inr = strlen(inp); + + nassigned = 0; + nconversions = 0; + nread = 0; + base = 0; /* XXX just to keep gcc happy */ + ccfn = NULL; /* XXX just to keep gcc happy */ + for (;;) { + c = *fmt++; + if (c == 0) + return (nassigned); + if (isspace(c)) { + while (inr > 0 && isspace(*inp)) + nread++, inr--, inp++; + continue; + } + if (c != '%') + goto literal; + width = 0; + flags = 0; + /* + * switch on the format. continue if done; + * break once format type is derived. + */ +again: c = *fmt++; + switch (c) { + case '%': +literal: + if (inr <= 0) + goto input_failure; + if (*inp != c) + goto match_failure; + inr--, inp++; + nread++; + continue; + + case '*': + flags |= SUPPRESS; + goto again; + case 'l': + if (flags & LONG) { + flags &= ~LONG; + flags |= QUAD; + } else { + flags |= LONG; + } + goto again; + case 'q': + flags |= QUAD; + goto again; + case 'h': + if (flags & SHORT) { + flags &= ~SHORT; + flags |= SHORTSHORT; + } else { + flags |= SHORT; + } + goto again; + + case '0': case '1': case '2': case '3': case '4': + case '5': case '6': case '7': case '8': case '9': + width = width * 10 + c - '0'; + goto again; + + /* + * Conversions. + * + */ + case 'd': + c = CT_INT; + ccfn = (ccfntype)strtoq; + base = 10; + break; + + case 'i': + c = CT_INT; + ccfn = (ccfntype)strtoq; + base = 0; + break; + + case 'o': + c = CT_INT; + ccfn = strtouq; + base = 8; + break; + + case 'u': + c = CT_INT; + ccfn = strtouq; + base = 10; + break; + + case 'x': + flags |= PFXOK; /* enable 0x prefixing */ + c = CT_INT; + ccfn = strtouq; + base = 16; + break; + + case 's': + c = CT_STRING; + break; + + case '[': + fmt = __sccl(ccltab, fmt); + flags |= NOSKIP; + c = CT_CCL; + break; + + case 'c': + flags |= NOSKIP; + c = CT_CHAR; + break; + + case 'p': /* pointer format is like hex */ + flags |= POINTER | PFXOK; + c = CT_INT; + ccfn = strtouq; + base = 16; + break; + + case 'n': + nconversions++; + if (flags & SUPPRESS) /* ??? */ + continue; + if (flags & SHORTSHORT) + *va_arg(ap, char *) = nread; + else if (flags & SHORT) + *va_arg(ap, short *) = nread; + else if (flags & LONG) + *va_arg(ap, long *) = nread; + else if (flags & QUAD) + *va_arg(ap, s64 *) = nread; + else + *va_arg(ap, int *) = nread; + continue; + } + + /* + * We have a conversion that requires input. + */ + if (inr <= 0) + goto input_failure; + + /* + * Consume leading white space, except for formats + * that suppress this. + */ + if ((flags & NOSKIP) == 0) { + while (isspace(*inp)) { + nread++; + if (--inr > 0) + inp++; + else + goto input_failure; + } + /* + * Note that there is at least one character in + * the buffer, so conversions that do not set NOSKIP + * can no longer result in an input failure. + */ + } + + /* + * Do the conversion. + */ + switch (c) { + case CT_CHAR: + /* scan arbitrary characters (sets NOSKIP) */ + if (width == 0) + width = 1; + if (flags & SUPPRESS) { + size_t sum = 0; + + if ((n = inr) < width) { + sum += n; + width -= n; + inp += n; + if (sum == 0) + goto input_failure; + } else { + sum += width; + inr -= width; + inp += width; + } + nread += sum; + } else { + memcpy(va_arg(ap, char *), inp, width); + inr -= width; + inp += width; + nread += width; + nassigned++; + } + nconversions++; + break; + + case CT_CCL: + /* scan a (nonempty) character class (sets NOSKIP) */ + if (width == 0) + width = (size_t)~0; /* `infinity' */ + /* take only those things in the class */ + if (flags & SUPPRESS) { + n = 0; + while (ccltab[(unsigned char)*inp]) { + n++, inr--, inp++; + if (--width == 0) + break; + if (inr <= 0) { + if (n == 0) + goto input_failure; + break; + } + } + if (n == 0) + goto match_failure; + } else { + p = va_arg(ap, char *); + p0 = p; + while (ccltab[(unsigned char)*inp]) { + inr--; + *p++ = *inp++; + if (--width == 0) + break; + if (inr <= 0) { + if (p == p0) + goto input_failure; + break; + } + } + n = p - p0; + if (n == 0) + goto match_failure; + *p = 0; + nassigned++; + } + nread += n; + nconversions++; + break; + + case CT_STRING: + /* like CCL, but zero-length string OK, & no NOSKIP */ + if (width == 0) + width = (size_t)~0; + if (flags & SUPPRESS) { + n = 0; + while (!isspace(*inp)) { + n++, inr--, inp++; + if (--width == 0) + break; + if (inr <= 0) + break; + } + nread += n; + } else { + p = va_arg(ap, char *); + p0 = p; + while (!isspace(*inp)) { + inr--; + *p++ = *inp++; + if (--width == 0) + break; + if (inr <= 0) + break; + } + *p = 0; + nread += p - p0; + nassigned++; + } + nconversions++; + continue; + + case CT_INT: + /* scan an integer as if by strtoq/strtouq */ +#ifdef hardway + if (width == 0 || width > sizeof(buf) - 1) + width = sizeof(buf) - 1; +#else + /* size_t is unsigned, hence this optimisation */ + if (--width > sizeof(buf) - 2) + width = sizeof(buf) - 2; + width++; +#endif + flags |= SIGNOK | NDIGITS | NZDIGITS; + for (p = buf; width; width--) { + c = *inp; + /* + * Switch on the character; `goto ok' + * if we accept it as a part of number. + */ + switch (c) { + /* + * The digit 0 is always legal, but is + * special. For %i conversions, if no + * digits (zero or nonzero) have been + * scanned (only signs), we will have + * base==0. In that case, we should set + * it to 8 and enable 0x prefixing. + * Also, if we have not scanned zero digits + * before this, do not turn off prefixing + * (someone else will turn it off if we + * have scanned any nonzero digits). + */ + case '0': + if (base == 0) { + base = 8; + flags |= PFXOK; + } + if (flags & NZDIGITS) + flags &= ~(SIGNOK | NZDIGITS | NDIGITS); + else + flags &= ~(SIGNOK | PFXOK | NDIGITS); + goto ok; + + /* 1 through 7 always legal */ + case '1': case '2': case '3': + case '4': case '5': case '6': case '7': + base = basefix[base]; + flags &= ~(SIGNOK | PFXOK | NDIGITS); + goto ok; + + /* digits 8 and 9 ok iff decimal or hex */ + case '8': case '9': + base = basefix[base]; + if (base <= 8) + break; /* not legal here */ + flags &= ~(SIGNOK | PFXOK | NDIGITS); + goto ok; + + /* letters ok iff hex */ + case 'A': case 'B': case 'C': + case 'D': case 'E': case 'F': + case 'a': case 'b': case 'c': + case 'd': case 'e': case 'f': + /* no need to fix base here */ + if (base <= 10) + break; /* not legal here */ + flags &= ~(SIGNOK | PFXOK | NDIGITS); + goto ok; + + /* sign ok only as first character */ + case '+': case '-': + if (flags & SIGNOK) { + flags &= ~SIGNOK; + goto ok; + } + break; + + /* x ok iff flag still set & 2nd char */ + case 'x': case 'X': + if (flags & PFXOK && p == buf + 1) { + base = 16; /* if %i */ + flags &= ~PFXOK; + goto ok; + } + break; + } + + /* + * If we got here, c is not a legal character + * for a number. Stop accumulating digits. + */ + break; +ok: + /* + * c is legal: store it and look at the next. + */ + *p++ = c; + if (--inr > 0) + inp++; + else + break; /* end of input */ + } + /* + * If we had only a sign, it is no good; push + * back the sign. If the number ends in `x', + * it was [sign] '' 'x', so push back the x + * and treat it as [sign] ''. + */ + if (flags & NDIGITS) { + if (p > buf) { + inp--; + inr++; + } + goto match_failure; + } + c = ((u_char *)p)[-1]; + if (c == 'x' || c == 'X') { + --p; + inp--; + inr++; + } + if ((flags & SUPPRESS) == 0) { + u64 res; + + *p = 0; + res = (*ccfn)(buf, (char **)NULL, base); + if (flags & POINTER) + *va_arg(ap, void **) = + (void *)(uintptr_t)res; + else if (flags & SHORTSHORT) + *va_arg(ap, char *) = res; + else if (flags & SHORT) + *va_arg(ap, short *) = res; + else if (flags & LONG) + *va_arg(ap, long *) = res; + else if (flags & QUAD) + *va_arg(ap, s64 *) = res; + else + *va_arg(ap, int *) = res; + nassigned++; + } + nread += p - buf; + nconversions++; + break; + } + } +input_failure: + return (nconversions != 0 ? nassigned : -1); +match_failure: + return (nassigned); +} + +/** + * sscanf - Unformat a buffer into a list of arguments + * @buf: input buffer + * @fmt: formatting of buffer + * @...: resulting arguments + */ +int sscanf(const char *buf, const char *fmt, ...) +{ + va_list args; + int i; + + va_start(args, fmt); + i = vsscanf(buf, fmt, args); + va_end(args); + return i; +} + +#endif |