rk3288 u-boot sscanf实现

$ vi ./lib/vsprintf.c

#define USHRT_MAX     ((u16)(~0U))
#define SHRT_MAX     ((s16)(USHRT_MAX>>1))

/**
* simple_strtoll - convert a string to a signed long long
* @cp: The start of the string
* @endp: A pointer to the end of the parsed string will be placed here
* @base: The number base to use
*/
long long simple_strtoll(const char *cp, char **endp, unsigned int base)
{
if (*cp == '-')
return -simple_strtoull(cp + 1, endp, base);

return simple_strtoull(cp, endp, base);
}

/* Convert a character to lower case */
__inline__ static char
_tolower (char c)
{
if ((c >= 'A') && (c <= 'Z'))
{
c = (c - 'A') + 'a';
}
return c;
}

/**
* vsscanf - Unformat a buffer into a list of arguments
* @buf:     input buffer
* @fmt:     format of buffer
* @args:     arguments
*/
int vsscanf(const char *buf, const char *fmt, va_list args)
{
const char *str = buf;
char *next;
char digit;
int num = 0;
u8 qualifier;
u8 base;
s16 field_width;
char is_sign;

while (*fmt && *str) {
/* skip any white space in format */
/* white space in format matchs any amount of
* white space, including none, in the input.
*/
if (isspace(*fmt)) {
fmt = skip_spaces(++fmt);
str = skip_spaces(str);
}

/* anything that is not a conversion must match exactly */
if (*fmt != '%' && *fmt) {
if (*fmt++ != *str++)
break;
continue;
}

if (!*fmt)
break;
++fmt;

/* skip this conversion.
* advance both strings to next white space
*/
if (*fmt == '*') {
while (!isspace(*fmt) && *fmt != '%' && *fmt)
fmt++;
while (!isspace(*str) && *str)
str++;
continue;
}

/* get field width */
field_width = -1;
if (isdigit(*fmt))
field_width = skip_atoi(&fmt);

/* get conversion qualifier */
qualifier = -1;
if (*fmt == 'h' || _tolower(*fmt) == 'l' ||
_tolower(*fmt) == 'z') {
qualifier = *fmt++;
if (unlikely(qualifier == *fmt)) {
if (qualifier == 'h') {
qualifier = 'H';
fmt++;
} else if (qualifier == 'l') {
qualifier = 'L';
fmt++;
}
}
}

if (!*fmt || !*str)
break;

base = 10;
is_sign = 0;

switch (*fmt++) {
case 'c':
{
char *s = (char *)va_arg(args, char*);
if (field_width == -1)
field_width = 1;
do {
*s++ = *str++;
} while (--field_width > 0 && *str);
num++;
}
continue;
case 's':
{
char *s = (char *)va_arg(args, char *);
if (field_width == -1)
field_width = SHRT_MAX;
/* first, skip leading white space in buffer */
str = skip_spaces(str);

/* now copy until next white space */
while (*str && !isspace(*str) && field_width--)
*s++ = *str++;
*s = '\0';
num++;
}
continue;
case 'n':
/* return number of characters read so far */
{
int *i = (int *)va_arg(args, int*);
*i = str - buf;
}
continue;
case 'o':
base = 8;
break;
case 'x':
case 'X':
base = 16;
break;
case 'i':
base = 0;
case 'd':
is_sign = 1;
case 'u':
break;
case '%':
/* looking for '%' in str */
if (*str++ != '%')
return num;
continue;
default:
/* invalid format; stop here */
return num;
}

/* have some sort of integer conversion.
* first, skip white space in buffer.
*/
str = skip_spaces(str);

digit = *str;
if (is_sign && digit == '-')
digit = *(str + 1);

if (!digit
|| (base == 16 && !isxdigit(digit))
|| (base == 10 && !isdigit(digit))
|| (base == 8 && (!isdigit(digit) || digit > '7'))
|| (base == 0 && !isdigit(digit)))
break;

switch (qualifier) {
case 'H':     /* that's 'hh' in format */
if (is_sign) {
signed char *s = (signed char *)va_arg(args, signed char *);
*s = (signed char)simple_strtol(str, &next, base);
} else {
unsigned char *s = (unsigned char *)va_arg(args, unsigned char *);
*s = (unsigned char)simple_strtoul(str, &next, base);
}
break;
case 'h':
if (is_sign) {
short *s = (short *)va_arg(args, short *);
*s = (short)simple_strtol(str, &next, base);
} else {
unsigned short *s = (unsigned short *)va_arg(args, unsigned short *);
*s = (unsigned short)simple_strtoul(str, &next, base);
}
break;
case 'l':
if (is_sign) {
long *l = (long *)va_arg(args, long *);
*l = simple_strtol(str, &next, base);
} else {
unsigned long *l = (unsigned long *)va_arg(args, unsigned long *);
*l = simple_strtoul(str, &next, base);
}
break;
case 'L':
if (is_sign) {
long long *l = (long long *)va_arg(args, long long *);
*l = simple_strtoll(str, &next, base);
} else {
unsigned long long *l = (unsigned long long *)va_arg(args, unsigned long long *);
*l = simple_strtoull(str, &next, base);
}
break;
case 'Z':
case 'z':
{
size_t *s = (size_t *)va_arg(args, size_t *);
*s = (size_t)simple_strtoul(str, &next, base);
}
break;
default:
if (is_sign) {
int *i = (int *)va_arg(args, int *);
*i = (int)simple_strtol(str, &next, base);
} else {
unsigned int *i = (unsigned int *)va_arg(args, unsigned int*);
*i = (unsigned int)simple_strtoul(str, &next, base);
}
break;
}
num++;

if (!next)
break;
str = next;
}

/*
* Now we've come all the way through so either the input string or the
* format ended. In the former case, there can be a %n at the current
* position in the format that needs to be filled.
*/
if (*fmt == '%' && *(fmt + 1) == 'n') {
int *p = (int *)va_arg(args, int *);
*p = str - buf;
}

return num;
}
/**
* 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;
}

2,

#include <stdio.h>
#include <assert.h>
#define KEYVALLEN 100

char *l_trim(char *szOutput, const char *szInput)
{
assert(szInput != NULL);
assert(szOutput != NULL);
assert(szOutput != szInput);
for(NULL; *szInput != '\0' && isspace(*szInput); ++szInput){
;
}
return strcpy(szOutput, szInput);
}

/* 删除两边的空格 */
char * a_trim(char *szOutput, const char *szInput)
{
char *p = NULL;
assert(szInput != NULL);
assert(szOutput != NULL);
l_trim(szOutput, szInput);
for(p = szOutput + strlen(szOutput) - 1;p >= szOutput && isspace(*p); --p){
;
}
*(++p) = '\0';
return szOutput;
}

void delspace(char * p)
{
int i,j=0;
for ( i = 0; p[i] != '\0'; i++ ) {
if(p[i] != ' ')
p[j++] = p[i];
}
p[j] = '\0';
}
int main(void)
{
char buf[] = " jiangdou = 1988 ";

char *p = buf;
char keyname[32];
char buf_i[KEYVALLEN], buf_o[KEYVALLEN];

a_trim(buf_o, buf);
//delspace(buf_o);
printf("buf_o is:%s\n", buf_o);
p = buf_o;
delspace(p);
//sscanf(p, "%[^=|^ |^\t]", keyname);

printf("%s\n", p);
}


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