Re: [PATCH 1/2] msgb: Add msgb_hexdump() function

On Fri, Feb 28, 2014 at 08:47:45PM +0100, Jacob Erlbeck wrote:

Good morning Jacob,

as usual thank you very much for your work.

This function works like osmo_hexdump() and return a static buffer

^ returns

containing hex bytes along with markes for the layers.

^ markers

+/*! \brief Return (static) buffer containing a hexdump of the msg

^ Return "a"

+const char *msgb_hexdump(const struct msgb *msg) +{

• static char buf[4100];
• int buf_offs = 0;
• int nchars;
• const unsigned char *start = msg->data;
• const unsigned char *lxhs[4];
• int i;
• lxhs[0] = msg->l1h;
• lxhs[1] = msg->l2h;
• lxhs[2] = msg->l3h;
• lxhs[3] = msg->l4h;
• for (i = 0; i < ARRAY_SIZE(lxhs); i++) {

• if (lxhs[i]) {
  

if (!lxhs[i]) continue;

This avoids having the show at three levels of indention in.

• 	nchars = snprintf(buf + buf_offs, sizeof(buf) - buf_offs,
  

• 			  "%s[L%d]> ",
  

• 			  osmo_hexdump(start, lxhs[i] - start),
  

• 			  i+1);
  

• nchars = snprintf(buf + buf_offs, sizeof(buf) - buf_offs,

• 	  "%s", osmo_hexdump(start, msg->tail - start));
  

• nchars = snprintf(buf, sizeof(buf) - buf_offs,

• 	  "!!! L%d out of range", i+1);
  

So sizeof(buf) - buf_offs can only be 0 when the output is already null terminated?

kind regards holger