Add new binary conversion bifs

Added: binary_to_integer/1,2, integer_to_binary/1,2
jzmq · Feb 14, 2013 · b074099 · b074099
1 parent e55aff9
commit b074099
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Showing 14 changed files with 736 additions and 218 deletions.
diff --git a/erts/doc/src/erlang.xml b/erts/doc/src/erlang.xml
@@ -299,6 +299,32 @@
         <p>Failure: <c>badarg</c> if the atom does not already exist.</p>
       </desc>
     </func>
+    <func>
+      <name name="binary_to_integer" arity="1"/>
+      <fsummary>Convert from text representation to an integer</fsummary>
+      <desc>
+        <p>Returns an integer whose text representation is
+          <c><anno>Binary</anno></c>.</p>
+        <pre>
+> <input>binary_to_integer(&lt;&lt;"123"&gt;&gt;).</input>
+123</pre>
+        <p>Failure: <c>badarg</c> if <c><anno>Binary</anno></c> contains a bad
+          representation of an integer.</p>
+      </desc>
+    </func>
+    <func>
+      <name name="binary_to_integer" arity="2"/>
+      <fsummary>Convert from text representation to an integer</fsummary>
+      <desc>
+        <p>Returns an integer whose text representation in base
+          <c><anno>Base</anno></c> is <c><anno>Binary</anno></c>.</p>
+        <pre>
+> <input>binary_to_integer(&lt;&lt;"3FF"&gt;&gt;, 16).</input>
+1023</pre>
+        <p>Failure: <c>badarg</c> if <c><anno>Binary</anno></c> contains a bad
+          representation of an integer.</p>
+      </desc>
+    </func>
     <func>
       <name name="binary_to_list" arity="1"/>
       <fsummary>Convert a binary to a list</fsummary>
@@ -1429,7 +1455,28 @@ os_prompt% </pre>
 {one,new,two,three}</pre>
       </desc>
     </func>
-
+    <func>
+      <name name="integer_to_binary" arity="1"/>
+      <fsummary>Text representation of an integer</fsummary>
+      <desc>
+        <p>Returns a binary which corresponds to the text
+          representation of <c><anno>Integer</anno></c>.</p>
+        <pre>
+> <input>integer_to_binary(77).</input>
+&lt;&lt;"77">></pre>
+      </desc>
+    </func>
+    <func>
+      <name name="integer_to_binary" arity="2"/>
+      <fsummary>Text representation of an integer</fsummary>
+      <desc>
+        <p>Returns a binary which corresponds to the text
+          representation of <c><anno>Integer</anno></c> in base <c><anno>Base</anno></c>.</p>
+        <pre>
+> <input>integer_to_binary(1023, 16).</input>
+&lt;&lt;"3FF">></pre>
+      </desc>
+    </func>
     <func>
       <name name="integer_to_list" arity="1"/>
       <fsummary>Text representation of an integer</fsummary>

diff --git a/erts/emulator/beam/bif.c b/erts/emulator/beam/bif.c
@@ -2895,20 +2895,64 @@ BIF_RETTYPE string_to_integer_1(BIF_ALIST_1)
 	 BIF_RET(TUPLE2(hp, res, tail));
      }
 }
-
 
 BIF_RETTYPE list_to_integer_1(BIF_ALIST_1)
-{
+ {
+   /* Using do_list_to_integer is about twice as fast as using 
+      erts_chars_to_integer because we do not have to copy the 
+      entire list */
      Eterm res;
      Eterm dummy;
      /* must be a list */
-
      if (do_list_to_integer(BIF_P,BIF_ARG_1,&res,&dummy) != LTI_ALL_INTEGER) {
 	 BIF_ERROR(BIF_P,BADARG);
      }
      BIF_RET(res);
  }
 
+BIF_RETTYPE list_to_integer_2(BIF_ALIST_2)
+{
+
+  /* Bif implementation is about 50% faster than pure erlang,
+     and since we have erts_chars_to_integer now it is simpler
+     as well. This could be optmized further if we did not have to
+     copy the list to buf. */
+    int i;
+    Eterm res;
+    char *buf = NULL;
+    int base;
+
+    i = list_length(BIF_ARG_1);
+    if (i < 0)
+      BIF_ERROR(BIF_P, BADARG);
+
+    base = signed_val(BIF_ARG_2);
+
+    if (base < 2 || base > 36) 
+      BIF_ERROR(BIF_P, BADARG);
+
+    /* Take fast path if base it 10 */
+    if (base == 10)
+      return list_to_integer_1(BIF_P,&BIF_ARG_1);
+
+    buf = (char *) erts_alloc(ERTS_ALC_T_TMP, i + 1);
+
+    if (intlist_to_buf(BIF_ARG_1, buf, i) < 0)
+      goto list_to_integer_1_error;
+    buf[i] = '\0';		/* null terminal */
+
+    if ((res = erts_chars_to_integer(BIF_P,buf,i,base)) == THE_NON_VALUE)
+      goto list_to_integer_1_error;
+
+    erts_free(ERTS_ALC_T_TMP, (void *) buf);
+    BIF_RET(res);
+
+ list_to_integer_1_error:
+    erts_free(ERTS_ALC_T_TMP, (void *) buf);
+    BIF_ERROR(BIF_P, BADARG);
+
+ }
+
 /**********************************************************************/
 
 /* convert a float to a list of ascii characters */

diff --git a/erts/emulator/beam/bif.tab b/erts/emulator/beam/bif.tab
@@ -561,6 +561,10 @@ bif erlang:prepare_loading/2
 bif erlang:finish_loading/1
 bif erlang:insert_element/3
 bif erlang:delete_element/2
+bif erlang:binary_to_integer/1
+bif erlang:binary_to_integer/2
+bif erlang:integer_to_binary/1
+bif erlang:list_to_integer/2
 
 #
 # Obsolete