coreboot-kgpe-d16/payloads/libpayload/libc/string.c

656 lines
15 KiB
C

/*
*
* Copyright (C) 2007 Uwe Hermann <uwe@hermann-uwe.de>
* Copyright (C) 2008 Advanced Micro Devices, Inc.
* Copyright (C) 2010 coresystems GmbH
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <libpayload.h>
#include <string.h>
#include <ctype.h>
#include <inttypes.h>
#include <limits.h>
#include <errno.h>
/**
* Calculate the length of a fixed-size string.
*
* @param str The input string.
* @param maxlen Return at most maxlen characters as length of the string.
* @return The length of the string, not including the final NUL character.
* The maximum length returned is maxlen.
*/
size_t strnlen(const char *str, size_t maxlen)
{
size_t len = 0;
/* NULL and empty strings have length 0. */
if (!str)
return 0;
/* Loop until we find a NUL character, or maxlen is reached. */
while ((*str++ != '\0') && (len < maxlen))
len++;
return len;
}
/**
* Calculate the length of a string.
*
* @param str The input string.
* @return The length of the string, not including the final NUL character.
*/
size_t strlen(const char *str)
{
size_t len = 0;
/* NULL and empty strings have length 0. */
if (!str)
return 0;
/* Loop until we find a NUL character. */
while (*str++ != '\0')
len++;
return len;
}
/**
* Compare two strings.
*
* @param s1 The first string.
* @param s2 The second string.
* @return Returns a value less than zero, if s1 is shorter than s2. Returns
* zero, if s1 equals s2. Returns a value greater than zero, if
* s1 is longer than s2.
*/
int strcasecmp(const char *s1, const char *s2)
{
int res;
for (size_t i = 0; 1; i++) {
res = tolower(s1[i]) - tolower(s2[i]);
if (res || (s1[i] == '\0'))
break;
}
return res;
}
/**
* Compare two strings with fixed length.
*
* @param s1 The first string.
* @param s2 The second string.
* @param maxlen Return at most maxlen characters as length of the string.
* @return A non-zero value if s1 and s2 differ, or zero if s1 equals s2.
*/
int strncasecmp(const char *s1, const char *s2, size_t maxlen)
{
int res = 0;
for (size_t i = 0; i < maxlen; i++) {
res = tolower(s1[i]) - tolower(s2[i]);
if (res || (s1[i] == '\0'))
break;
}
return res;
}
/**
* Compare two strings.
*
* @param s1 The first string.
* @param s2 The second string.
* @return Returns a value less than zero, if s1 is shorter than s2. Returns
* zero, if s1 equals s2. Returns a value greater than zero, if
* s1 is longer than s2.
*/
int strcmp(const char *s1, const char *s2)
{
int res;
for (size_t i = 0; 1; i++) {
res = s1[i] - s2[i];
if (res || (s1[i] == '\0'))
break;
}
return res;
}
/**
* Compare two strings with fixed length.
*
* @param s1 The first string.
* @param s2 The second string.
* @param maxlen Return at most maxlen characters as length of the string.
* @return A non-zero value if s1 and s2 differ, or zero if s1 equals s2.
*/
int strncmp(const char *s1, const char *s2, size_t maxlen)
{
int res = 0;
for (size_t i = 0; i < maxlen; i++) {
res = s1[i] - s2[i];
if (res || (s1[i] == '\0'))
break;
}
return res;
}
/**
* Copy a string with a maximum length.
*
* @param d The destination memory.
* @param s The source string.
* @param n Copy at most n characters as length of the string.
* @return A pointer to the destination memory.
*/
char *strncpy(char *d, const char *s, size_t n)
{
/* Use +1 to get the NUL terminator. */
size_t max = n > strlen(s) + 1 ? strlen(s) + 1 : n;
for (size_t i = 0; i < max; i++)
d[i] = (char)s[i];
return d;
}
/**
* Copy a string.
*
* @param d The destination memory.
* @param s The source string.
* @return A pointer to the destination memory.
*/
char *strcpy(char *d, const char *s)
{
return strncpy(d, s, strlen(s) + 1);
}
/**
* Concatenates two strings
*
* @param d The destination string.
* @param s The source string.
* @return A pointer to the destination string.
*/
char *strcat(char *d, const char *s)
{
char *p = d + strlen(d);
size_t sl = strlen(s);
for (size_t i = 0; i < sl; i++)
p[i] = s[i];
p[sl] = '\0';
return d;
}
/**
* Concatenates two strings with a maximum length.
*
* @param d The destination string.
* @param s The source string.
* @param n Not more than n characters from s will be appended to d.
* @return A pointer to the destination string.
*/
char *strncat(char *d, const char *s, size_t n)
{
char *p = d + strlen(d);
size_t sl = strlen(s);
size_t max = n > sl ? sl : n;
for (size_t i = 0; i < max; i++)
p[i] = s[i];
p[max] = '\0';
return d;
}
/**
* Concatenates two strings with a maximum length.
*
* @param d The destination string.
* @param s The source string.
* @param n d will have at most n-1 characters (plus NUL) after invocation.
* @return The total length of the concatenated string.
*/
size_t strlcat(char *d, const char *s, size_t n)
{
size_t sl = strlen(s);
size_t dl = strlen(d);
if (n <= dl + 1)
return sl + dl;
char *p = d + dl;
size_t max = n > (sl + dl) ? sl : (n - dl - 1);
for (size_t i = 0; i < max; i++)
p[i] = s[i];
p[max] = '\0';
return sl + dl;
}
/**
* Find a character in a string.
*
* @param s The string.
* @param c The character.
* @return A pointer to the first occurrence of the character in the
* string, or NULL if the character was not encountered within the string.
*/
char *strchr(const char *s, int c)
{
char *p = (char *)s;
for (; *p != 0; p++) {
if (*p == c)
return p;
}
return NULL;
}
/**
* Find a character in a string.
*
* @param s The string.
* @param c The character.
* @return A pointer to the last occurrence of the character in the
* string, or NULL if the character was not encountered within the string.
*/
char *strrchr(const char *s, int c)
{
char *p = (char *)s + strlen(s);
for (; p >= s; p--) {
if (*p == c)
return p;
}
return NULL;
}
/**
* Duplicate a string.
*
* @param s The string to duplicate.
* @return A pointer to the copy of the original string.
*/
char *strdup(const char *s)
{
size_t n = strlen(s);
char *p = malloc(n + 1);
if (p != NULL) {
strncpy(p, s, n);
p[n] = 0;
}
return p;
}
/**
* Find a substring within a string.
*
* @param h The haystack string.
* @param n The needle string (substring).
* @return A pointer to the first occurrence of the substring in
* the string, or NULL if the substring was not encountered within the string.
*/
char *strstr(const char *h, const char *n)
{
size_t hn = strlen(h);
size_t nn = strlen(n);
if (hn < nn)
return NULL;
for (size_t i = 0; i <= hn - nn; i++)
if (!memcmp(&h[i], n, nn))
return (char *)&h[i];
return NULL;
}
/**
* Separate strings.
*
* @param stringp reference of the string to separate.
* @param delim string containing all delimiters.
* @return Token string.
*/
char *strsep(char **stringp, const char *delim)
{
char *walk, *token;
if (!stringp || !*stringp || !**stringp)
return NULL;
token = walk = *stringp;
/* Walk, search for delimiters */
while (*walk && !strchr(delim, *walk))
walk++;
if (*walk) {
/* NUL terminate */
*walk = '\0';
walk++;
}
*stringp = walk;
return token;
}
/* Check that a character is in the valid range for the
given base
*/
static int _valid(char ch, int base)
{
char end = (base > 9) ? '9' : '0' + (base - 1);
/* all bases will be some subset of the 0-9 range */
if (ch >= '0' && ch <= end)
return 1;
/* Bases > 11 will also have to match in the a-z range */
if (base > 11) {
if (tolower(ch) >= 'a' &&
tolower(ch) <= 'a' + (base - 11))
return 1;
}
return 0;
}
/* Return the "value" of the character in the given base */
static int _offset(char ch, int base)
{
if (ch >= '0' && ch <= '9')
return ch - '0';
else
return 10 + tolower(ch) - 'a';
}
/**
* Convert the initial portion of a string into a signed int
* @param ptr A pointer to the string to convert
* @param endptr A pointer to the unconverted part of the string
* @param base The base of the number to convert, or 0 for auto
* @return A signed integer representation of the string
*/
long long int strtoll(const char *orig_ptr, char **endptr, int base)
{
const char *ptr = orig_ptr;
int is_negative = 0;
/* Purge whitespace */
for ( ; *ptr && isspace(*ptr); ptr++);
if (ptr[0] == '-') {
is_negative = 1;
ptr++;
}
unsigned long long uval = strtoull(ptr, endptr, base);
/* If the whole string is unparseable, endptr should point to start. */
if (endptr && *endptr == ptr)
*endptr = (char *)orig_ptr;
if (uval > (unsigned long long)LLONG_MAX + !!is_negative)
uval = (unsigned long long)LLONG_MAX + !!is_negative;
if (is_negative)
return -uval;
else
return uval;
}
long int strtol(const char *ptr, char **endptr, int base)
{
long long int val = strtoll(ptr, endptr, base);
if (val > LONG_MAX)
return LONG_MAX;
if (val < LONG_MIN)
return LONG_MIN;
return val;
}
long atol(const char *nptr)
{
return strtol(nptr, NULL, 10);
}
/**
* Convert the initial portion of a string into an unsigned int
* @param ptr A pointer to the string to convert
* @param endptr A pointer to the unconverted part of the string
* @param base The base of the number to convert, or 0 for auto
* @return An unsigned integer representation of the string
*/
unsigned long long int strtoull(const char *ptr, char **endptr, int base)
{
unsigned long long int ret = 0;
if (endptr != NULL)
*endptr = (char *) ptr;
/* Purge whitespace */
for ( ; *ptr && isspace(*ptr); ptr++);
if (!*ptr)
return 0;
/* Determine the base */
if (base == 0) {
if (ptr[0] == '0' && (ptr[1] == 'x' || ptr[1] == 'X'))
base = 16;
else if (ptr[0] == '0') {
base = 8;
ptr++;
} else {
base = 10;
}
}
/* Base 16 allows the 0x on front - so skip over it */
if (base == 16) {
if (ptr[0] == '0' && (ptr[1] == 'x' || ptr[1] == 'X') &&
_valid(ptr[2], base))
ptr += 2;
}
for ( ; *ptr && _valid(*ptr, base); ptr++)
ret = (ret * base) + _offset(*ptr, base);
if (endptr != NULL)
*endptr = (char *) ptr;
return ret;
}
unsigned long int strtoul(const char *ptr, char **endptr, int base)
{
unsigned long long val = strtoull(ptr, endptr, base);
if (val > ULONG_MAX)
return ULONG_MAX;
return val;
}
/**
* Determine the number of leading characters in s that match characters in a
* @param s A pointer to the string to analyse
* @param a A pointer to an array of characters that match the prefix
* @return The number of matching characters
*/
size_t strspn(const char *s, const char *a)
{
size_t i;
size_t al = strlen(a);
for (i = 0; s[i] != 0; i++) {
int found = 0;
for (size_t j = 0; j < al; j++) {
if (s[i] == a[j]) {
found = 1;
break;
}
}
if (!found)
break;
}
return i;
}
/**
* Determine the number of leading characters in s that do not match characters in a
* @param s A pointer to the string to analyse
* @param a A pointer to an array of characters that do not match the prefix
* @return The number of not matching characters
*/
size_t strcspn(const char *s, const char *a)
{
size_t i;
size_t al = strlen(a);
for (i = 0; s[i] != 0; i++) {
int found = 0;
for (size_t j = 0; j < al; j++) {
if (s[i] == a[j]) {
found = 1;
break;
}
}
if (found)
break;
}
return i;
}
/**
* Extract first token in string str that is delimited by a character in tokens.
* Destroys str and eliminates the token delimiter.
* @param str A pointer to the string to tokenize.
* @param delim A pointer to an array of characters that delimit the token
* @param ptr A pointer to a string pointer to keep state of the tokenizer
* @return Pointer to token
*/
char *strtok_r(char *str, const char *delim, char **ptr)
{
/* start new tokenizing job or continue existing one? */
if (str == NULL)
str = *ptr;
/* skip over prefix delimiters */
char *start = str + strspn(str, delim);
if (start[0] == '\0')
return NULL;
/* find first delimiter character */
char *end = start + strcspn(start, delim);
*ptr = end;
if (end[0] != '\0')
*(*ptr)++ = '\0';
return start;
}
/**
* Extract first token in string str that is delimited by a character in tokens.
* Destroys str, eliminates the token delimiter and uses global state.
* @param str A pointer to the string to tokenize.
* @param delim A pointer to an array of characters that delimit the token
* @return Pointer to token
*/
char *strtok(char *str, const char *delim)
{
static char *strtok_ptr;
return strtok_r(str, delim, &strtok_ptr);
}
/**
* Print error message and error number
* @param s Error message to print
*/
void perror(const char *s)
{
printf("%s: %d\n", s?s:"(none)", errno);
}
/**
* Get a message string describing the given error number.
*
* @param errnum The error number to be interpreted
* @return A pointer to a string describing the given error number
*/
char *strerror(int errnum)
{
/* Reserve enough space for the string below + INT64_MIN in decimal + \0 */
static char errstr[35];
snprintf(errstr, sizeof(errstr), "Unknown error %d", errnum);
return errstr;
}
/*
* Simple routine to convert UTF-16 to ASCII, giving up with ? if too high.
* A single code point may convert to ?? if not in the BMP.
* @param utf16_string A string encoded in UTF-16LE
* @param maxlen Maximum possible length of the string in code points
* @return Newly allocated ASCII string
*/
char *utf16le_to_ascii(const uint16_t *utf16_string, size_t maxlen)
{
char *ascii_string = xmalloc(maxlen + 1); /* +1 for trailing \0 */
ascii_string[maxlen] = '\0';
for (size_t i = 0; i < maxlen; i++) {
uint16_t wchar = utf16_string[i];
ascii_string[i] = wchar > 0x7f ? '?' : (char)wchar;
}
return ascii_string;
}