improve str_to_buf and buf_to_str helpers

[openocd.git] / src / helper / binarybuffer.c

diff --git a/src/helper/binarybuffer.c b/src/helper/binarybuffer.c
index 95e084efa41da465bc8d0d1d855484d4de834f54..0def9485530afd834cf956b71b4efd4926bd05b4 100644 (file)
--- a/src/helper/binarybuffer.c
+++ b/src/helper/binarybuffer.c
@@ -169,43 +169,36 @@ int ceil_f_to_u32(float x)
        return y;
 }
 
-char* buf_to_str(const uint8_t *buf, int buf_len, int radix)
+char* buf_to_str(const void *_buf, unsigned buf_len, unsigned radix)
 {
-       const char *DIGITS = "0123456789ABCDEF";
        float factor;
-       char *str;
-       int str_len;
-       int b256_len = CEIL(buf_len, 8);
-       uint32_t tmp;
-
-       int j; /* base-256 digits */
-       int i; /* output digits (radix) */
-
-       if (radix == 16)
-       {
+       switch (radix) {
+       case 16:
                factor = 2.0;   /* log(256) / log(16) = 2.0 */
-       }
-       else if (radix == 10)
-       {
+               break;
+       case 10:
                factor = 2.40824;   /* log(256) / log(10) = 2.40824 */
-       }
-       else if (radix == 8)
-       {
+               break;
+       case 8:
                factor = 2.66667;       /* log(256) / log(8) = 2.66667 */
-       }
-       else
+               break;
+       default:
                return NULL;
+       }
 
-       str_len = ceil_f_to_u32(CEIL(buf_len, 8) * factor);
-       str = calloc(str_len + 1, 1);
+       unsigned str_len = ceil_f_to_u32(CEIL(buf_len, 8) * factor);
+       char *str = calloc(str_len + 1, 1);
 
-       for (i = b256_len - 1; i >= 0; i--)
+       const uint8_t *buf = _buf;
+       int b256_len = CEIL(buf_len, 8);
+       for (int i = b256_len - 1; i >= 0; i--)
        {
-               tmp = buf[i];
-               if ((i == (buf_len / 8)) && (buf_len % 8))
+               uint32_t tmp = buf[i];
+               if (((unsigned)i == (buf_len / 8)) && (buf_len % 8))
                        tmp &= (0xff >> (8 - (buf_len % 8)));
 
-               for (j = str_len; j > 0; j--)
+               /* base-256 digits */
+               for (unsigned j = str_len; j > 0; j--)
                {
                        tmp += (uint32_t)str[j-1] * 256;
                        str[j-1] = (uint8_t)(tmp % radix);
@@ -213,44 +206,49 @@ char* buf_to_str(const uint8_t *buf, int buf_len, int radix)
                }
        }
 
-       for (j = 0; j < str_len; j++)
+       const char *DIGITS = "0123456789ABCDEF";
+       for (unsigned j = 0; j < str_len; j++)
                str[j] = DIGITS[(int)str[j]];
 
        return str;
 }
 
-int str_to_buf(const char *str, int str_len, uint8_t *buf, int buf_len, int radix)
+/// identify radix, and skip radix-prefix (0, 0x or 0X)
+static void str_radix_guess(const char **_str, unsigned *_str_len,
+               unsigned *_radix)
 {
-       char *charbuf;
-       uint32_t tmp;
-       float factor;
-       uint8_t *b256_buf;
-       int b256_len;
-
-       int j; /* base-256 digits */
-       int i; /* input digits (ASCII) */
-
-       if (radix == 0)
+       unsigned radix = *_radix;
+       if (0 != radix)
+               return;
+       const char *str = *_str;
+       unsigned str_len = *_str_len;   
+       if (str[0] == '0' && (str[1] == 'x' || str[1] == 'X'))
        {
-               /* identify radix, and skip radix-prefix (0, 0x or 0X) */
-               if ((str[0] == '0') && (str[1] && ((str[1] == 'x') || (str[1] == 'X'))))
-               {
-                       radix = 16;
-                       str += 2;
-                       str_len -= 2;
-               }
-               else if ((str[0] == '0') && (str_len != 1))
-               {
-                       radix = 8;
-                       str += 1;
-                       str_len -= 1;
-               }
-               else
-               {
-                       radix = 10;
-               }
+               radix = 16;
+               str += 2;
+               str_len -= 2;
        }
+       else if ((str[0] == '0') && (str_len != 1))
+       {
+               radix = 8;
+               str += 1;
+               str_len -= 1;
+       }
+       else
+       {
+               radix = 10;
+       }
+       *_str = str;
+       *_str_len = str_len;
+       *_radix = radix;
+}
+
+int str_to_buf(const char *str, unsigned str_len,
+               void *_buf, unsigned buf_len, unsigned radix)
+{
+       str_radix_guess(&str, &str_len, &radix);
 
+       float factor;
        if (radix == 16)
                factor = 0.5; /* log(16) / log(256) = 0.5 */
        else if (radix == 10)
@@ -261,18 +259,20 @@ int str_to_buf(const char *str, int str_len, uint8_t *buf, int buf_len, int radi
                return 0;
 
        /* copy to zero-terminated buffer */
-       charbuf = malloc(str_len + 1);
+       char *charbuf = malloc(str_len + 1);
        memcpy(charbuf, str, str_len);
        charbuf[str_len] = '\0';
 
        /* number of digits in base-256 notation */
-       b256_len = ceil_f_to_u32(str_len * factor);
-       b256_buf = calloc(b256_len, 1);
+       unsigned b256_len = ceil_f_to_u32(str_len * factor);
+       uint8_t *b256_buf = calloc(b256_len, 1);
 
        /* go through zero terminated buffer */
+       /* input digits (ASCII) */
+       unsigned i;
        for (i = 0; charbuf[i]; i++)
        {
-               tmp = charbuf[i];
+               uint32_t tmp = charbuf[i];
                if ((tmp >= '0') && (tmp <= '9'))
                        tmp = (tmp - '0');
                else if ((tmp >= 'a') && (tmp <= 'f'))
@@ -281,10 +281,11 @@ int str_to_buf(const char *str, int str_len, uint8_t *buf, int buf_len, int radi
                        tmp = (tmp - 'A' + 10);
                else continue;  /* skip characters other than [0-9,a-f,A-F] */
 
-               if (tmp >= (uint32_t)radix)
+               if (tmp >= radix)
                        continue;       /* skip digits invalid for the current radix */
 
-               for (j = 0; j < b256_len; j++)
+               /* base-256 digits */
+               for (unsigned j = 0; j < b256_len; j++)
                {
                        tmp += (uint32_t)b256_buf[j] * radix;
                        b256_buf[j] = (uint8_t)(tmp & 0xFF);
@@ -293,7 +294,8 @@ int str_to_buf(const char *str, int str_len, uint8_t *buf, int buf_len, int radi
 
        }
 
-       for (j = 0; j < CEIL(buf_len, 8); j++)
+       uint8_t *buf = _buf;
+       for (unsigned j = 0; j < CEIL(buf_len, 8); j++)
        {
                if (j < b256_len)
                        buf[j] = b256_buf[j];