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author | Zack Weinberg <zackw@panix.com> | 2017-06-08 15:39:03 -0400 |
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committer | Zack Weinberg <zackw@panix.com> | 2017-06-08 15:39:03 -0400 |
commit | 5046dbb4a7eba5eccfd258f92f4735c9ffc8d069 (patch) | |
tree | 4470480d904b65cf14ca524f96f79eca818c3eaf /REORG.TODO/resolv/inet_ntop.c | |
parent | 199fc19d3aaaf57944ef036e15904febe877fc93 (diff) | |
download | glibc-5046dbb4a7eba5eccfd258f92f4735c9ffc8d069.tar.gz glibc-5046dbb4a7eba5eccfd258f92f4735c9ffc8d069.tar.xz glibc-5046dbb4a7eba5eccfd258f92f4735c9ffc8d069.zip |
Prepare for radical source tree reorganization. zack/build-layout-experiment
All top-level files and directories are moved into a temporary storage directory, REORG.TODO, except for files that will certainly still exist in their current form at top level when we're done (COPYING, COPYING.LIB, LICENSES, NEWS, README), all old ChangeLog files (which are moved to the new directory OldChangeLogs, instead), and the generated file INSTALL (which is just deleted; in the new order, there will be no generated files checked into version control).
Diffstat (limited to 'REORG.TODO/resolv/inet_ntop.c')
-rw-r--r-- | REORG.TODO/resolv/inet_ntop.c | 189 |
1 files changed, 189 insertions, 0 deletions
diff --git a/REORG.TODO/resolv/inet_ntop.c b/REORG.TODO/resolv/inet_ntop.c new file mode 100644 index 0000000000..01c45ce8b7 --- /dev/null +++ b/REORG.TODO/resolv/inet_ntop.c @@ -0,0 +1,189 @@ +/* + * Copyright (c) 1996-1999 by Internet Software Consortium. + * + * Permission to use, copy, modify, and distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS + * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE + * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL + * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR + * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS + * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS + * SOFTWARE. + */ + +#include <sys/param.h> +#include <sys/types.h> +#include <sys/socket.h> + +#include <netinet/in.h> +#include <arpa/inet.h> +#include <arpa/nameser.h> + +#include <errno.h> +#include <stdio.h> +#include <string.h> + +#ifdef SPRINTF_CHAR +# define SPRINTF(x) strlen(sprintf/**/x) +#else +# define SPRINTF(x) ((size_t)sprintf x) +#endif + +/* + * WARNING: Don't even consider trying to compile this on a system where + * sizeof(int) < 4. sizeof(int) > 4 is fine; all the world's not a VAX. + */ + +static const char *inet_ntop4 (const u_char *src, char *dst, socklen_t size) + internal_function; +static const char *inet_ntop6 (const u_char *src, char *dst, socklen_t size) + internal_function; + +/* char * + * inet_ntop(af, src, dst, size) + * convert a network format address to presentation format. + * return: + * pointer to presentation format address (`dst'), or NULL (see errno). + * author: + * Paul Vixie, 1996. + */ +const char * +inet_ntop (int af, const void *src, char *dst, socklen_t size) +{ + switch (af) { + case AF_INET: + return (inet_ntop4(src, dst, size)); + case AF_INET6: + return (inet_ntop6(src, dst, size)); + default: + __set_errno (EAFNOSUPPORT); + return (NULL); + } + /* NOTREACHED */ +} +libc_hidden_def (inet_ntop) + +/* const char * + * inet_ntop4(src, dst, size) + * format an IPv4 address + * return: + * `dst' (as a const) + * notes: + * (1) uses no statics + * (2) takes a u_char* not an in_addr as input + * author: + * Paul Vixie, 1996. + */ +static const char * +internal_function +inet_ntop4 (const u_char *src, char *dst, socklen_t size) +{ + static const char fmt[] = "%u.%u.%u.%u"; + char tmp[sizeof "255.255.255.255"]; + + if (SPRINTF((tmp, fmt, src[0], src[1], src[2], src[3])) >= size) { + __set_errno (ENOSPC); + return (NULL); + } + return strcpy(dst, tmp); +} + +/* const char * + * inet_ntop6(src, dst, size) + * convert IPv6 binary address into presentation (printable) format + * author: + * Paul Vixie, 1996. + */ +static const char * +internal_function +inet_ntop6 (const u_char *src, char *dst, socklen_t size) +{ + /* + * 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; + u_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; + best.len = 0; + 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; + } + 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) { + __set_errno (ENOSPC); + return (NULL); + } + return strcpy(dst, tmp); +} |