changeset 1352:577f6535e787

Cleanup pass on host.c
author Rob Landley <rob@landley.net>
date Wed, 11 Jun 2014 22:14:44 -0500
parents 0f2b9d0b1f7a
children 2102af52be68
files toys/pending/host.c
diffstat 1 files changed, 47 insertions(+), 84 deletions(-) [+]
line wrap: on
line diff
--- a/toys/pending/host.c	Wed Jun 11 22:13:28 2014 -0500
+++ b/toys/pending/host.c	Wed Jun 11 22:14:44 2014 -0500
@@ -67,12 +67,11 @@
 
 void host_main(void)
 {
-  int verbose=(toys.optflags & (FLAG_a|FLAG_v)), type;
-  char *name, *nsname;
-  int i, j, ret, sec, count, rcode, qlen, alen, pllen = 0;
+  int verbose=(toys.optflags & (FLAG_a|FLAG_v)), type,
+      i, j, ret, sec, count, rcode, qlen, alen, pllen = 0;
   unsigned ttl, pri, v[5];
   unsigned char qbuf[280], abuf[512], *p;
-  char rrname[256], plname[640], ptrbuf[64];
+  char *name, *nsname, rrname[256], plname[640], ptrbuf[64];
   struct addrinfo *ai, iplit_hints = { .ai_flags = AI_NUMERICHOST };
 
   name = *toys.optargs;
@@ -80,16 +79,14 @@
 
   if (!TT.type_str && (toys.optflags & FLAG_a)) TT.type_str = "255";
   if (!getaddrinfo(name, 0, &iplit_hints, &ai)) {
-    switch (ai->ai_family) {
-      unsigned char *a;
-      static const char xdigits[] = "0123456789abcdef";
-    case AF_INET:
+    unsigned char *a;
+    static const char xdigits[] = "0123456789abcdef";
+
+    if (ai->ai_family == AF_INET) {
       a = (void *)&((struct sockaddr_in *)ai->ai_addr)->sin_addr;
-      snprintf(ptrbuf, sizeof ptrbuf,
-        "%d.%d.%d.%d.in-addr.arpa",
+      snprintf(ptrbuf, sizeof(ptrbuf), "%d.%d.%d.%d.in-addr.arpa",
         a[3], a[2], a[1], a[0]);
-      break;
-    case AF_INET6:
+    } else if (ai->ai_family == AF_INET6) {
       a = (void *)&((struct sockaddr_in6 *)ai->ai_addr)->sin6_addr;
       for (j=0, i=15; i>=0; i--) {
         ptrbuf[j++] = xdigits[a[i]&15];
@@ -98,17 +95,13 @@
         ptrbuf[j++] = '.';
       }
       strcpy(ptrbuf+j, "ip6.arpa");
-      break;
     }
     name = ptrbuf;
     if (!TT.type_str) TT.type_str="12";
-  } else {
-    if (!TT.type_str) TT.type_str="1";
-  }
+  } else if (!TT.type_str) TT.type_str="1";
 
-  if (TT.type_str[0]-'0' < 10u) {
-    type = atoi(TT.type_str);
-  } else {
+  if (TT.type_str[0]-'0' < 10u) type = atoi(TT.type_str);
+  else {
     type = -1;
     for (i=0; i < sizeof rrt / sizeof *rrt; i++) {
       if (rrt[i].name && !strcasecmp(TT.type_str, rrt[i].name)) {
@@ -117,76 +110,57 @@
       }
     }
     if (!strcasecmp(TT.type_str, "any")) type = 255;
-    if (type < 0) {
-      fprintf(stderr, "Invalid query type: %s\n", TT.type_str);
-      goto out_error;
-    }
+    if (type < 0) error_exit("Invalid query type: %s", TT.type_str);
   }
 
   qlen = res_mkquery(0, name, 1, type, 0, 0, 0, qbuf, sizeof qbuf);
-  if (qlen < 0) {
-    fprintf(stderr, "Invalid query parameters: %s", name);
-    goto out_error;
-  }
+  if (qlen < 0) error_exit("Invalid query parameters: %s", name);
 
   if (nsname) {
     struct addrinfo ns_hints = { .ai_socktype = SOCK_DGRAM };
-    if ((ret = getaddrinfo(nsname, "53", &ns_hints, &ai)) < 0) {
-      fprintf(stderr, "Error looking up server name: %s\n",
-        gai_strerror(ret));
-      goto out_error;
-    }
+
+    if ((ret = getaddrinfo(nsname, "53", &ns_hints, &ai)) < 0)
+      error_exit("Error looking up server name: %s", gai_strerror(ret));
     int s = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
-    if (s < 0 || connect(s, ai->ai_addr, ai->ai_addrlen) < 0) {
-      fprintf(stderr, "Socket error: %s\n", strerror(errno));
-      goto out_error;
-    }
-    setsockopt(s, SOL_SOCKET, SO_RCVTIMEO,
-      &(struct timeval){ .tv_sec = 5 },
-      sizeof (struct timeval));
+    if (s < 0 || connect(s, ai->ai_addr, ai->ai_addrlen) < 0)
+      perror_exit("Socket error");
+    setsockopt(s, SOL_SOCKET, SO_RCVTIMEO, &(struct timeval){ .tv_sec = 5 },
+      sizeof(struct timeval));
     printf("Using domain server %s:\n", nsname);
     send(s, qbuf, qlen, 0);
     alen = recv(s, abuf, sizeof abuf, 0);
-  } else {
-    alen = res_send(qbuf, qlen, abuf, sizeof abuf);
-  }
+  } else alen = res_send(qbuf, qlen, abuf, sizeof abuf);
 
-  if (alen < 12) {
-    fprintf(stderr, "Host not found, try again.\n");
-    goto out_error;
-  }
+  if (alen < 12) error_exit("Host not found.");
 
   rcode = abuf[3] & 15;
 
   if (verbose) {
     printf("rcode = %d (%s), ancount = %d\n",
       rcode, rct[rcode], 256*abuf[6] + abuf[7]);
-    if (!(abuf[2] & 4))
-      printf("The following answer is not authoritative:\n");
+    if (!(abuf[2] & 4)) printf("The following answer is not authoritative:\n");
   }
 
-  if (rcode) {
-    fprintf(stderr, "Host not found.\n");
-    if (!verbose) goto out_error;
-  }
+  if (rcode) error_exit("Host not found.");
 
   p = abuf + 12;
   for (sec=0; sec<4; sec++) {
     count = 256*abuf[4+2*sec] + abuf[5+2*sec];
-    if (verbose && count>0 && sec>1) {
+    if (verbose && count>0 && sec>1) 
       puts(sec==2 ? "For authoritative answers, see:"
         : "Additional information:");
-    }
+
     for (; count--; p += pllen) {
-      p += dn_expand(abuf, abuf+alen, p, rrname, sizeof rrname);
-      type = 256*p[0] + p[1];
+      p += dn_expand(abuf, abuf+alen, p, rrname, sizeof(rrname));
+      type = (p[0]<<8) + p[1];
       p += 4;
       if (!sec) continue;
-      ttl = 16777216*p[0] + 65536*p[1] + 256*p[2] + p[3];
+      ttl = (p[0]<<24)+(p[1]<<16)+(p[2]<<8)+p[3];
       p += 4;
-      pllen = 256*p[0] + p[1];
+      pllen = (p[0]<<8) + p[1];
       p += 2;
-      switch (type<sizeof rrt/sizeof *rrt ? rrt[type].pl : 0) {
+
+      switch (type<sizeof(rrt)/sizeof(*rrt) ? rrt[type].pl : 0) {
       case PL_IP:
         inet_ntop(rrt[type].af, p, plname, sizeof plname);
         break;
@@ -200,12 +174,10 @@
         i = dn_expand(abuf, abuf+alen, p, plname, sizeof plname - 1);
         strcat(plname, " ");
         i += dn_expand(abuf, abuf+alen, p+i, plname+strlen(plname),
-          sizeof plname-strlen(plname));
+          sizeof(plname)-strlen(plname));
         for (j=0; j<5; j++)
-          v[j] = 16777216u*p[i+4*j] + 65536*p[1+i+4*j]
-            + 256*p[2+i+4*j] + p[3+i+4*j];
-        snprintf(plname+strlen(plname),
-          sizeof plname-strlen(plname),
+          v[j] = (p[i+4*j]<<24)+(p[1+i+4*j]<<16)+(p[2+i+4*j]<<8)+p[3+i+4*j];
+        snprintf(plname+strlen(plname), sizeof(plname)-strlen(plname),
           "(\n\t\t%u\t;serial (version)\n"
           "\t\t%u\t;refresh period\n"
           "\t\t%u\t;retry interval\n"
@@ -214,38 +186,29 @@
           "\t\t)", v[0], v[1], v[2], v[3], v[4]);
         break;
       case PL_MX:
-        pri = 256*p[0] + p[1];
-        snprintf(plname, sizeof plname,
-          verbose ? "%d " : "(pri=%d) by ", pri);
-        dn_expand(abuf, abuf+alen, p+2,
-          plname+strlen(plname),
+        pri = (p[0]<<8)+p[1];
+        snprintf(plname, sizeof(plname), verbose ? "%d " : "(pri=%d) by ", pri);
+        dn_expand(abuf, abuf+alen, p+2, plname+strlen(plname),
           sizeof plname - strlen(plname));
         break;
       case PL_SRV:
-        for (j=0; j<3; j++)
-          v[j] = 256*p[2*j] + p[1+2*j];
-        snprintf(plname, sizeof plname,
-          "%u %u %u ", v[0], v[1], v[2]);
-        dn_expand(abuf, abuf+alen, p+6,
-          plname+strlen(plname),
+        for (j=0; j<3; j++) v[j] = (p[2*j]<<8) + p[1+2*j];
+        snprintf(plname, sizeof(plname), "%u %u %u ", v[0], v[1], v[2]);
+        dn_expand(abuf, abuf+alen, p+6, plname+strlen(plname),
           sizeof plname - strlen(plname));
         break;
       default:
         printf("%s unsupported RR type %u\n", rrname, type);
         continue;
       }
-      if (verbose) {
-        printf("%s\t%u\t%s %s\t%s\n",
-          rrname, ttl, "IN", rrt[type].name, plname);
-      } else if (rrt[type].msg) {
+
+      if (verbose)
+        printf("%s\t%u\tIN %s\t%s\n", rrname, ttl, rrt[type].name, plname);
+      else if (rrt[type].msg)
         printf("%s %s %s\n", rrname, rrt[type].msg, plname);
-      }
     }
     if (!verbose && sec==1) break;
   }
+
   toys.exitval = rcode;
-  return;
-
-out_error:
-  toys.exitval = 1;
 }