- /*
- * Note that int32_t and int16_t need only be "at least" large enough
- * to contain a value of the specified size. On some systems, like
- * Crays, there is no such thing as an integer variable with 16 bits.
- * Keep this in mind if you think this function should have been coded
- * to use pointer overlays. All the world's not a VAX.
- */
- char tmp[sizeof "ffff:ffff:ffff:ffff:ffff:ffff:255.255.255.255"], *tp;
- struct { int base, len; } best, cur;
- unsigned int words[NS_IN6ADDRSZ / NS_INT16SZ];
- int i;
-
- /*
- * Preprocess:
- * Copy the input (bytewise) array into a wordwise array.
- * Find the longest run of 0x00's in src[] for :: shorthanding.
- */
- memset(words, '\0', sizeof words);
- for (i = 0; i < NS_IN6ADDRSZ; i += 2)
- words[i / 2] = (src[i] << 8) | src[i + 1];
- best.base = -1;
- cur.base = -1;
- for (i = 0; i < (NS_IN6ADDRSZ / NS_INT16SZ); i++) {
- if (words[i] == 0) {
- if (cur.base == -1)
- cur.base = i, cur.len = 1;
- else
- cur.len++;
- } else {
- if (cur.base != -1) {
- if (best.base == -1 || cur.len > best.len)
- best = cur;
- cur.base = -1;
- }
- }
- }
- if (cur.base != -1) {
- if (best.base == -1 || cur.len > best.len)
- best = cur;
- }
- if (best.base != -1 && best.len < 2)
- best.base = -1;
-
- /*
- * Format the result.
- */
- tp = tmp;
- for (i = 0; i < (NS_IN6ADDRSZ / NS_INT16SZ); i++) {
- /* Are we inside the best run of 0x00's? */
- if (best.base != -1 && i >= best.base &&
- i < (best.base + best.len)) {
- if (i == best.base)
- *tp++ = ':';
- continue;
- }
- /* Are we following an initial run of 0x00s or any real hex? */
- if (i != 0)
- *tp++ = ':';
- /* Is this address an encapsulated IPv4? */
- if (i == 6 && best.base == 0 &&
- (best.len == 6 || (best.len == 5 && words[5] == 0xffff))) {
- if (!inet_ntop4(src+12, tp, sizeof tmp - (tp - tmp)))
- return (NULL);
- tp += strlen(tp);
- break;
- }
- tp += sprintf(tp, "%x", words[i]);
- }
- /* Was it a trailing run of 0x00's? */
- if (best.base != -1 && (best.base + best.len) ==
- (NS_IN6ADDRSZ / NS_INT16SZ))
- *tp++ = ':';
- *tp++ = '\0';
-
- /*
- * Check for overflow, copy, and we're done.
- */
- if ((socklen_t)(tp - tmp) > size) {
- errno = ENOSPC;
- return (NULL);
- }
- return strcpy(dst, tmp);
+ /*
+ * Note that int32_t and int16_t need only be "at least" large enough
+ * to contain a value of the specified size. On some systems, like
+ * Crays, there is no such thing as an integer variable with 16 bits.
+ * Keep this in mind if you think this function should have been coded
+ * to use pointer overlays. All the world's not a VAX.
+ */
+ char tmp[sizeof "ffff:ffff:ffff:ffff:ffff:ffff:255.255.255.255"], *tp;
+ struct
+ {
+ int base, len;
+ } best, cur;
+ unsigned int words[NS_IN6ADDRSZ / NS_INT16SZ];
+ int i;
+
+ /*
+ * Preprocess:
+ * Copy the input (bytewise) array into a wordwise array.
+ * Find the longest run of 0x00's in src[] for :: shorthanding.
+ */
+ memset (words, '\0', sizeof words);
+ for (i = 0; i < NS_IN6ADDRSZ; i += 2)
+ words[i / 2] = (src[i] << 8) | src[i + 1];
+ best.base = -1;
+ cur.base = -1;
+ IF_LINT(best.len = 0);
+ IF_LINT(cur.len = 0);
+ for (i = 0; i < (NS_IN6ADDRSZ / NS_INT16SZ); i++)
+ {
+ if (words[i] == 0)
+ {
+ if (cur.base == -1)
+ cur.base = i, cur.len = 1;
+ else
+ cur.len++;
+ }
+ else
+ {
+ if (cur.base != -1)
+ {
+ if (best.base == -1 || cur.len > best.len)
+ best = cur;
+ cur.base = -1;
+ }
+ }
+ }
+ if (cur.base != -1)
+ {
+ if (best.base == -1 || cur.len > best.len)
+ best = cur;
+ }
+ if (best.base != -1 && best.len < 2)
+ best.base = -1;
+
+ /*
+ * Format the result.
+ */
+ tp = tmp;
+ for (i = 0; i < (NS_IN6ADDRSZ / NS_INT16SZ); i++)
+ {
+ /* Are we inside the best run of 0x00's? */
+ if (best.base != -1 && i >= best.base && i < (best.base + best.len))
+ {
+ if (i == best.base)
+ *tp++ = ':';
+ continue;
+ }
+ /* Are we following an initial run of 0x00s or any real hex? */
+ if (i != 0)
+ *tp++ = ':';
+ /* Is this address an encapsulated IPv4? */
+ if (i == 6 && best.base == 0 &&
+ (best.len == 6 || (best.len == 5 && words[5] == 0xffff)))
+ {
+ if (!inet_ntop4 (src + 12, tp, sizeof tmp - (tp - tmp)))
+ return (NULL);
+ tp += strlen (tp);
+ break;
+ }
+ {
+ int len = sprintf (tp, "%x", words[i]);
+ if (len < 0)
+ return NULL;
+ tp += len;
+ }
+ }
+ /* Was it a trailing run of 0x00's? */
+ if (best.base != -1 && (best.base + best.len) ==
+ (NS_IN6ADDRSZ / NS_INT16SZ))
+ *tp++ = ':';
+ *tp++ = '\0';
+
+ /*
+ * Check for overflow, copy, and we're done.
+ */
+ if ((socklen_t) (tp - tmp) > size)
+ {
+ errno = ENOSPC;
+ return NULL;
+ }
+
+ return strcpy (dst, tmp);