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 100char *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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