From: Michael Gernoth Date: Thu, 30 May 2013 10:27:00 +0000 (+0200) Subject: get rid of strtoul/printf for ascii-hex/bin conversion X-Git-Tag: v0.100~97 X-Git-Url: https://git.zerfleddert.de/cgi-bin/gitweb.cgi/hmcfgusb/commitdiff_plain/51d4ece67f9843cef2eaebc84fb7e98716fe28ab get rid of strtoul/printf for ascii-hex/bin conversion --- diff --git a/hmland.c b/hmland.c index 8e5a8e9..c8781a9 100644 --- a/hmland.c +++ b/hmland.c @@ -56,6 +56,8 @@ static int verbose = 0; static int format_part_out(uint8_t **inpos, int inlen, uint8_t **outpos, int outlen, int len, int flags) { + const uint8_t nibble[16] = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', + 'A', 'B', 'C', 'D', 'E', 'F'}; uint8_t *buf_out = *outpos; uint8_t *outend = *outpos + outlen; uint8_t *inend = *inpos + inlen; @@ -74,20 +76,13 @@ static int format_part_out(uint8_t **inpos, int inlen, uint8_t **outpos, int out } if (flags & FLAG_FORMAT_HEX) { - char hex[3]; - - memset(hex, 0, sizeof(hex)); - CHECK_AVAIL(len); CHECK_SPACE(len*2); for (i = 0; i < len; i++) { - if (snprintf(hex, sizeof(hex), "%02X", **inpos) != 2) { - fprintf(stderr, "Can't format hex-string!\n"); - return 0; - } - *inpos += 1; - memcpy(*outpos, hex, 2); - *outpos += 2; + **outpos = nibble[((**inpos) & 0xf0) >> 4]; + *outpos += 1; + **outpos = nibble[((**inpos) & 0xf)]; + *inpos += 1; *outpos += 1; } } else { CHECK_AVAIL(len); @@ -114,14 +109,26 @@ static int format_part_out(uint8_t **inpos, int inlen, uint8_t **outpos, int out return *outpos - buf_out; } +static uint8_t ascii_to_nibble(uint8_t a) +{ + uint8_t c = 0x00; + + if ((a >= '0') && (a <= '9')) { + c = a - '0'; + } else if ((a >= 'A') && (a <= 'F')) { + c = (a - 'A') + 10; + } else if ((a >= 'a') && (a <= 'f')) { + c = (a - 'a') + 10; + } + + return c; +} + static int parse_part_in(uint8_t **inpos, int inlen, uint8_t **outpos, int outlen, int flags) { uint8_t *buf_out = *outpos; uint8_t *outend = *outpos + outlen; uint8_t *inend = *inpos + inlen; - char hex[3]; - - memset(hex, 0, sizeof(hex)); if (flags & FLAG_LENGTH_BYTE) { int len = 0; @@ -155,11 +162,11 @@ static int parse_part_in(uint8_t **inpos, int inlen, uint8_t **outpos, int outle CHECK_SPACE(1); CHECK_AVAIL(2); - memcpy(hex, *inpos, 2); - *inpos += 2; - **outpos = strtoul(hex, NULL, 16); - *outpos += 1; + **outpos = ascii_to_nibble(**inpos) << 4; + *inpos += 1; + **outpos |= ascii_to_nibble(**inpos); + *inpos += 1; *outpos += 1; } return *outpos - buf_out;