diff options
Diffstat (limited to 'libqcdm/src/utils.c')
| -rw-r--r-- | libqcdm/src/utils.c | 27 |
1 files changed, 26 insertions, 1 deletions
diff --git a/libqcdm/src/utils.c b/libqcdm/src/utils.c index 00685282..62574691 100644 --- a/libqcdm/src/utils.c +++ b/libqcdm/src/utils.c @@ -78,7 +78,6 @@ crc16 (const char *buffer, gsize len) return ~crc; } -#define DIAG_CONTROL_CHAR 0x7E #define DIAG_ESC_CHAR 0x7D /* Escape sequence 1st character value */ #define DIAG_ESC_MASK 0x20 /* Escape sequence complement value */ @@ -167,3 +166,29 @@ dm_unescape (const char *inbuf, return outsize; } +gsize +dm_prepare_buffer (char *inbuf, + gsize cmd_len, + gsize inbuf_len, + char *outbuf, + gsize outbuf_len) +{ + guint16 crc; + gsize escaped_len; + + g_return_val_if_fail (inbuf != NULL, 0); + g_return_val_if_fail (cmd_len >= 1, 0); + g_return_val_if_fail (inbuf_len >= cmd_len + 2, 0); /* space for CRC */ + g_return_val_if_fail (outbuf != NULL, 0); + + crc = GUINT16_TO_LE (crc16 (inbuf, cmd_len)); + inbuf[cmd_len++] = crc & 0xFF; + inbuf[cmd_len++] = (crc >> 8) & 0xFF; + + escaped_len = dm_escape (inbuf, cmd_len, outbuf, outbuf_len); + g_return_val_if_fail (outbuf_len > escaped_len, 0); + outbuf[escaped_len++] = DIAG_CONTROL_CHAR; + + return escaped_len; +} + |