Added getprotobyname/getprotobynumber

The implementations of the getproto* functions follow from the getserv*
functions: same static name allocation, same type of internal function
that opens a file to search, aliases are not written to the struct, same
type of error handling/returns.

Note that in Windows, the protocols file was "<wherever>\\etc\\protocol"
ie the name is in singular.
This commit is contained in:
ahgamut 2021-07-06 21:11:59 +05:30
parent d6a028f2fb
commit f888f25858
5 changed files with 302 additions and 8 deletions

47
libc/dns/getprotobyname.c Normal file
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@ -0,0 +1,47 @@
/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8 :vi
This is free and unencumbered software released into the public domain.
Anyone is free to copy, modify, publish, use, compile, sell, or
distribute this software, either in source code form or as a compiled
binary, for any purpose, commercial or non-commercial, and by any
means.
In jurisdictions that recognize copyright laws, the author or authors
of this software dedicate any and all copyright interest in the
software to the public domain. We make this dedication for the benefit
of the public at large and to the detriment of our heirs and
successors. We intend this dedication to be an overt act of
relinquishment in perpetuity of all present and future rights to this
software under copyright law.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR
OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
OTHER DEALINGS IN THE SOFTWARE.
*/
#include "libc/dns/ent.h"
#include "libc/dns/prototxt.h"
struct protoent *getprotobyname(const char *name) {
static struct protoent *ptr0, pe0;
static char p_name[DNS_NAME_MAX + 1];
if (!ptr0) {
pe0.p_name = p_name;
if (!(pe0.p_aliases = calloc(1, sizeof(char *)))) return NULL;
pe0.p_proto = -1;
ptr0 = &pe0;
}
ptr0->p_proto = LookupProtoByName(name, ptr0->p_name, DNS_NAME_MAX, NULL);
if (ptr0->p_proto == -1) return NULL;
return ptr0;
}

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@ -0,0 +1,47 @@
/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8 :vi
This is free and unencumbered software released into the public domain.
Anyone is free to copy, modify, publish, use, compile, sell, or
distribute this software, either in source code form or as a compiled
binary, for any purpose, commercial or non-commercial, and by any
means.
In jurisdictions that recognize copyright laws, the author or authors
of this software dedicate any and all copyright interest in the
software to the public domain. We make this dedication for the benefit
of the public at large and to the detriment of our heirs and
successors. We intend this dedication to be an overt act of
relinquishment in perpetuity of all present and future rights to this
software under copyright law.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR
OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
OTHER DEALINGS IN THE SOFTWARE.
*/
#include "libc/dns/ent.h"
#include "libc/dns/prototxt.h"
struct protoent *getprotobynumber(int proto) {
static struct protoent *ptr1, pe1;
static char p_name[DNS_NAME_MAX + 1];
if (!ptr1) {
pe1.p_name = p_name;
if (!(pe1.p_aliases = calloc(1, sizeof(char *)))) return NULL;
pe1.p_proto = -1;
ptr1 = &pe1;
}
if (LookupProtoByNumber(proto, ptr1->p_name, DNS_NAME_MAX, NULL) == -1)
return NULL;
ptr1->p_proto = proto;
return ptr1;
}

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@ -31,14 +31,6 @@ struct protoent *getprotoent(void) {
return NULL;
}
struct protoent *getprotobyname(const char *name) {
return NULL;
}
struct protoent *getprotobynumber(int proto) {
return NULL;
}
void setprotoent(int stayopen) {
}

190
libc/dns/prototxt.c Normal file
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/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8 :vi
This is free and unencumbered software released into the public domain.
Anyone is free to copy, modify, publish, use, compile, sell, or
distribute this software, either in source code form or as a compiled
binary, for any purpose, commercial or non-commercial, and by any
means.
In jurisdictions that recognize copyright laws, the author or authors
of this software dedicate any and all copyright interest in the
software to the public domain. We make this dedication for the benefit
of the public at large and to the detriment of our heirs and
successors. We intend this dedication to be an overt act of
relinquishment in perpetuity of all present and future rights to this
software under copyright law.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR
OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
OTHER DEALINGS IN THE SOFTWARE.
*/
#include "libc/dns/prototxt.h"
#include "libc/bits/safemacros.internal.h"
#include "libc/dce.h"
#include "libc/errno.h"
#include "libc/fmt/conv.h"
#include "libc/fmt/fmt.h"
#include "libc/macros.internal.h"
#include "libc/mem/mem.h"
#include "libc/nt/systeminfo.h"
#include "libc/runtime/runtime.h"
#include "libc/str/str.h"
static textwindows noinline char *GetNtProtocolsTxtPath(char *pathbuf,
uint32_t size) {
/* protocol, not plural */
const char *const kWinHostsPath = "\\drivers\\etc\\protocol";
uint32_t len = GetSystemDirectoryA(&pathbuf[0], size);
if (len && len + strlen(kWinHostsPath) + 1 < size) {
if (pathbuf[len] == '\\') pathbuf[len--] = '\0';
memcpy(&pathbuf[len], kWinHostsPath, strlen(kWinHostsPath) + 1);
return &pathbuf[0];
} else {
return NULL;
}
}
/**
* Opens and searches /etc/protocols to find name for a given number.
*
* format of /etc/protocols is like this:
*
* # comment
* # NAME PROTOCOL ALIASES
*
* ip 0 IP
* icmp 1 ICMP
*
* @param protonum is the protocol number
* @param buf is a buffer to store the official name of the protocol
* @param bufsize is the size of buf
* @param filepath is the location of the protocols file
* (if NULL, uses /etc/protocols)
* @returns 0 on success, -1 on error
*
* @note aliases are not read from the file.
*/
int LookupProtoByNumber(const int protonum, char *buf, size_t bufsize,
const char *filepath) {
FILE *f;
char *line;
char pathbuf[PATH_MAX];
const char *path;
size_t linesize;
int found;
char *name, *number, *comment, *tok;
if (!(path = filepath)) {
path = "/etc/protocols";
if (IsWindows()) {
path =
firstnonnull(GetNtProtocolsTxtPath(pathbuf, ARRAYLEN(pathbuf)), path);
}
}
if (bufsize == 0 || !(f = fopen(path, "r"))) {
return -1;
}
line = NULL;
linesize = 0;
found = 0;
while (found == 0 && (getline(&line, &linesize, f)) != -1) {
if ((comment = strchr(line, '#'))) *comment = '\0';
name = strtok_r(line, " \t\r\n\v", &tok);
number = strtok_r(NULL, " \t\r\n\v", &tok);
if (name && number && protonum == atoi(number)) {
strncpy(buf, name, bufsize);
found = 1;
}
}
free(line);
if (ferror(f)) {
errno = ferror(f);
return -1;
}
fclose(f);
if (!found) return -1;
return 0;
}
/**
* Opens and searches /etc/protocols to find number for a given name.
*
* @param protoname is a NULL-terminated string
* @param buf is a buffer to store the official name of the protocol
* @param bufsize is the size of buf
* @param filepath is the location of protocols file
* (if NULL, uses /etc/protocols)
* @returns -1 on error, or
* positive protocol number
*
* @note aliases are read from file for comparison, but not returned.
* @see LookupProtoByNumber
*/
int LookupProtoByName(const char *protoname, char *buf, size_t bufsize,
const char *filepath) {
FILE *f;
char *line;
char pathbuf[PATH_MAX];
const char *path;
size_t linesize;
int found, result;
char *name, *number, *alias, *comment, *tok;
if (!(path = filepath)) {
path = "/etc/protocols";
if (IsWindows()) {
path =
firstnonnull(GetNtProtocolsTxtPath(pathbuf, ARRAYLEN(pathbuf)), path);
}
}
if (bufsize == 0 || !(f = fopen(path, "r"))) {
return -1;
}
line = NULL;
linesize = 0;
found = 0;
result = -1;
while (found == 0 && (getline(&line, &linesize, f)) != -1) {
if ((comment = strchr(line, '#'))) *comment = '\0';
name = strtok_r(line, " \t\r\n\v", &tok);
number = strtok_r(NULL, "/ \t\r\n\v", &tok);
if (name && number) {
alias = name;
while (alias && strcasecmp(alias, protoname) != 0)
alias = strtok_r(NULL, " \t\r\n\v", &tok);
if (alias) /* alias matched with protoname */
{
result = atoi(number);
strncpy(buf, name, bufsize);
found = 1;
}
}
}
free(line);
if (ferror(f)) {
errno = ferror(f);
return -1;
}
fclose(f);
if (!found) return -1;
return result;
}

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libc/dns/prototxt.h Normal file
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#ifndef COSMOPOLITAN_LIBC_DNS_PROTOTXT_H_
#define COSMOPOLITAN_LIBC_DNS_PROTOTXT_H_
#include "libc/sock/sock.h"
#include "libc/stdio/stdio.h"
#if !(__ASSEMBLER__ + __LINKER__ + 0)
COSMOPOLITAN_C_START_
int LookupProtoByNumber(const int, char *, size_t, const char *)
paramsnonnull((2));
int LookupProtoByName(const char *, char *, size_t, const char *)
paramsnonnull((1, 2));
/* TODO: implement like struct HostsTxt? */
COSMOPOLITAN_C_END_
#endif /* !(__ASSEMBLER__ + __LINKER__ + 0) */
#endif /* COSMOPOLITAN_LIBC_DNS_PROTOTXT_H_ */