gethostbyname initial support

2 files changed, 85 insertions, 0 deletions

diff --git a/src/library.js b/src/library.js
index d072d946..5d97b41f 100644
--- a/src/library.js
+++ b/src/library.js
@@ -6344,6 +6344,49 @@ LibraryManager.library = {
   },
 
   // ==========================================================================
+  // netdb.h
+  // ==========================================================================
+
+  // All we can do is alias names to ips. you give this a name, it returns an
+  // "ip" that we later know to use as a name. There is no way to do actual
+  // name resolving clientside in a browser.
+  // we do the aliasing in 172.29.*.*, giving us 65536 possibilities
+  // note: lots of leaking here!
+  gethostbyname: function(name) {
+    name = Pointer_stringify(name);
+    if (!_gethostbyname.hostent_layout) {
+      _gethostbyname.hostent_layout = Runtime.generateStructInfo([
+        ['i8*', 'h_name'],
+        ['i8**', 'h_aliases'],
+        ['i32', 'h_addrtype'],
+        ['i32', 'h_length'],
+        ['i8**', 'h_addr_list'],
+      ]);
+      _gethostbyname.table = {};
+      _gethostbyname.id = 0;
+    }
+    var id = _gethostbyname.id++;
+    assert(id < 65535);
+    _gethostbyname.table[id] = name;
+    // generate hostent
+    var ret = _malloc(_gethostbyname.hostent_layout.__size__);
+    var nameBuf = _malloc(name.length+1);
+    writeStringToMemory(name, nameBuf);
+    setValue(ret+_gethostbyname.hostent_layout.h_name, nameBuf, 'i8*');
+    var aliasesBuf = _malloc(4);
+    setValue(aliasesBuf, 0, 'i8*');
+    setValue(ret+_gethostbyname.hostent_layout.h_aliases, aliasesBuf, 'i8**');
+    setValue(ret+_gethostbyname.hostent_layout.h_addrtype, {{{ cDefine("AF_INET") }}}, 'i32');
+    setValue(ret+_gethostbyname.hostent_layout.h_length, 4, 'i32');
+    var addrListBuf = _malloc(12);
+    setValue(addrListBuf, addrListBuf+8, 'i32*');
+    setValue(addrListBuf+4, 0, 'i32*');
+    setValue(addrListBuf+8, 172 | (29 << 8) | ((id & 0xff) << 16) | ((id & 0xff00) << 24), 'i32');
+    setValue(ret+_gethostbyname.hostent_layout.h_addr_list, addrListBuf, 'i8**');
+    return ret;
+  },
+
+  // ==========================================================================
   // sockets
   // ==========================================================================
 
diff --git a/tests/runner.py b/tests/runner.py
index c21844d4..2fe41a84 100755
--- a/tests/runner.py
+++ b/tests/runner.py
@@ -5079,6 +5079,48 @@ def process(filename):
       '''
       self.do_run(src, '*d4c3b2a1,e07235fe,f0cdab07,cdab,34122143,afbe*\n4e0ab4be\n')
 
+    def test_gethostbyname(self):
+      src = r'''
+        #include <netdb.h>
+        #include <stdio.h>
+
+        void test(char *hostname) {
+          hostent *host = gethostbyname(hostname);
+          if (!host) {
+            printf("no such thing\n");
+            return;
+          }
+          printf("%s : %d : %d\n", host->h_name, host->h_addrtype, host->h_length);
+          char **name = host->h_aliases;
+          while (*name) {
+            printf("- %s\n", *name);
+            name++;
+          }
+          name = host->h_addr_list;
+          while (name && *name) {
+            printf("* ");
+            for (int i = 0; i < host->h_length; i++)
+              printf("%d.", (*name)[i]);
+            printf("\n");
+            name++;
+          }
+        }
+
+        int main() {
+          test("www.cheezburger.com");
+          test("fail.on.this.never.work"); // we will "work" on this - because we are just making aliases of names to ips
+          test("localhost");
+          return 1;
+        }
+      '''
+      self.do_run(src, '''www.cheezburger.com : 1 : 4
+* -84.29.0.0.
+fail.on.this.never.work : 1 : 4
+* -84.29.1.0.
+localhost : 1 : 4
+* -84.29.2.0.
+''')
+
     def test_ctype(self):
       # The bit fiddling done by the macros using __ctype_b_loc requires this.
       Settings.CORRECT_SIGNS = 1