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#include "lookup.h"
#include "stdio_impl.h"
#include <ctype.h>
#include <errno.h>
#include <string.h>
#include <netinet/in.h>
int __get_resolv_conf(struct resolvconf *conf, char *search, size_t search_sz)
{
char line[256];
unsigned char _buf[256];
FILE *f, _f;
int nns = 0;
conf->ndots = 1;
conf->timeout = 5;
conf->attempts = 2;
if (search) *search = 0;
f = __fopen_rb_ca("/etc/resolv.conf", &_f, _buf, sizeof _buf);
if (!f) switch (errno) {
case ENOENT:
case ENOTDIR:
case EACCES:
goto no_resolv_conf;
default:
return -1;
}
while (fgets(line, sizeof line, f)) {
char *p, *z;
if (!strchr(line, '\n') && !feof(f)) {
/* Ignore lines that get truncated rather than
* potentially misinterpreting them. */
int c;
do c = getc(f);
while (c != '\n' && c != EOF);
continue;
}
if (!strncmp(line, "options", 7) && isspace(line[7])) {
p = strstr(line, "ndots:");
if (p && isdigit(p[6])) {
p += 6;
unsigned long x = strtoul(p, &z, 10);
if (z != p) conf->ndots = x > 15 ? 15 : x;
}
p = strstr(line, "attempts:");
if (p && isdigit(p[9])) {
p += 9;
unsigned long x = strtoul(p, &z, 10);
if (z != p) conf->attempts = x > 10 ? 10 : x;
}
p = strstr(line, "timeout:");
if (p && (isdigit(p[8]) || p[8]=='.')) {
p += 8;
unsigned long x = strtoul(p, &z, 10);
if (z != p) conf->timeout = x > 60 ? 60 : x;
}
continue;
}
if (!strncmp(line, "nameserver", 10) && isspace(line[10])) {
if (nns >= MAXNS) continue;
for (p=line+11; isspace(*p); p++);
for (z=p; *z && !isspace(*z); z++);
*z=0;
if (__lookup_ipliteral(conf->ns+nns, p, AF_UNSPEC) > 0)
nns++;
continue;
}
if (!search) continue;
if ((strncmp(line, "domain", 6) && strncmp(line, "search", 6))
|| !isspace(line[6]))
continue;
for (p=line+7; isspace(*p); p++);
size_t l = strlen(p);
/* This can never happen anyway with chosen buffer sizes. */
if (l >= search_sz) continue;
memcpy(search, p, l+1);
}
__fclose_ca(f);
no_resolv_conf:
if (!nns) {
__lookup_ipliteral(conf->ns, "127.0.0.1", AF_UNSPEC);
nns = 1;
}
conf->nns = nns;
return 0;
}
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