Escape < and & in SGML

This is not required in SGML, but will be in XML, so this is a step to
prepare for the conversion to XML.  (It is still not required to escape
>, but we did it here in some cases for symmetry.)

Add a command-line option to osx/onsgmls calls to warn about unescaped
occurrences in the future.

Author: Alexander Law <exclusion@gmail.com>
Author: Peter Eisentraut <peter.eisentraut@2ndquadrant.com>

doc/src/sgml/Makefile

@@ -66,10 +66,13 @@ ALLSGML := $(wildcard $(srcdir)/*.sgml $(srcdir)/ref/*.sgml) $(GENERATED_SGML)
 # Enable some extra warnings
 # -wfully-tagged needed to throw a warning on missing tags
 # for older tool chains, 2007-08-31
-# Note: try "make SPFLAGS=-wxml" to catch a lot of other dubious constructs,
-# in particular < and & that haven't been made into entities.  It's far too
-# noisy to turn on by default, unfortunately.
 override SPFLAGS += -wall -wno-unused-param -wno-empty -wfully-tagged
+# Additional warnings for XML compatibility.  The conditional is meant
+# to detect whether we are using OpenSP rather than the ancient
+# original SP.
+ifneq (,$(filter o%,$(notdir $(OSX))))
+override SPFLAGS += -wdata-delim
+endif
 
 
 ##

doc/src/sgml/array.sgml

@@ -654,7 +654,7 @@ SELECT * FROM
   For instance:
 
 <programlisting>
-SELECT * FROM sal_emp WHERE pay_by_quarter && ARRAY[10000];
+SELECT * FROM sal_emp WHERE pay_by_quarter &amp;&amp; ARRAY[10000];
 </programlisting>
 
   This and other array operators are further described in

doc/src/sgml/fdwhandler.sgml

@@ -696,9 +696,9 @@ IsForeignRelUpdatable (Relation rel);
      The return value should be a bit mask of rule event numbers indicating
      which operations are supported by the foreign table, using the
      <literal>CmdType</> enumeration; that is,
-     <literal>(1 << CMD_UPDATE) = 4</> for <command>UPDATE</>,
+     <literal>(1 &lt;&lt; CMD_UPDATE) = 4</> for <command>UPDATE</>,
-     <literal>(1 << CMD_INSERT) = 8</> for <command>INSERT</>, and
+     <literal>(1 &lt;&lt; CMD_INSERT) = 8</> for <command>INSERT</>, and
-     <literal>(1 << CMD_DELETE) = 16</> for <command>DELETE</>.
+     <literal>(1 &lt;&lt; CMD_DELETE) = 16</> for <command>DELETE</>.
     </para>
 
     <para>

doc/src/sgml/plpgsql.sgml

@@ -1823,8 +1823,8 @@ $BODY$
 BEGIN
     RETURN QUERY SELECT flightid
                    FROM flight
-                  WHERE flightdate >= $1
+                  WHERE flightdate >= $1
-                    AND flightdate < ($1 + 1);
+                    AND flightdate &lt; ($1 + 1);
 
     -- Since execution is not finished, we can check whether rows were returned
     -- and raise exception if not.

doc/src/sgml/ref/alter_operator.sgml

@@ -134,9 +134,9 @@ ALTER OPERATOR @@ (text, text) OWNER TO joe;
 </programlisting></para>
 
   <para>
-    Change the restriction and join selectivity estimator functions of a custom operator <literal>a && b</literal> for type <type>int[]</type>:
+    Change the restriction and join selectivity estimator functions of a custom operator <literal>a &amp;&amp; b</literal> for type <type>int[]</type>:
 <programlisting>
-ALTER OPERATOR && (_int4, _int4) SET (RESTRICT = _int_contsel, JOIN = _int_contjoinsel);
+ALTER OPERATOR &amp;&amp; (_int4, _int4) SET (RESTRICT = _int_contsel, JOIN = _int_contjoinsel);
 </programlisting></para>
 
  </refsect1>

doc/src/sgml/ref/create_view.sgml

@@ -466,7 +466,7 @@ CREATE VIEW comedies AS
 CREATE RECURSIVE VIEW public.nums_1_100 (n) AS
     VALUES (1)
 UNION ALL
-    SELECT n+1 FROM nums_1_100 WHERE n < 100;
+    SELECT n+1 FROM nums_1_100 WHERE n &lt; 100;
 </programlisting>
    Notice that although the recursive view's name is schema-qualified in this
    <command>CREATE</>, its internal self-reference is not schema-qualified.

doc/src/sgml/ref/pgtesttiming.sgml

@@ -94,7 +94,7 @@
    nanoseconds. This example from an Intel i7-860 system using a TSC clock
    source shows excellent performance:
 
-<screen>
+<screen><![CDATA[
 Testing timing overhead for 3 seconds.
 Per loop time including overhead: 35.96 ns
 Histogram of timing durations:
@@ -104,7 +104,7 @@ Histogram of timing durations:
      4      0.00015        126
      8      0.00002         13
     16      0.00000          2
-</screen>
+]]></screen>
   </para>
 
   <para>
@@ -152,7 +152,7 @@ EXPLAIN ANALYZE SELECT COUNT(*) FROM t;
    possible from switching to the slower acpi_pm time source, on the same
    system used for the fast results above:
 
-<screen>
+<screen><![CDATA[
 # cat /sys/devices/system/clocksource/clocksource0/available_clocksource
 tsc hpet acpi_pm
 # echo acpi_pm > /sys/devices/system/clocksource/clocksource0/current_clocksource
@@ -165,7 +165,7 @@ Histogram of timing durations:
      4      0.07810       3241
      8      0.01357        563
     16      0.00007          3
-</screen>
+]]></screen>
   </para>
 
   <para>
@@ -201,7 +201,7 @@ kern.timecounter.hardware: ACPI-fast -> TSC
    implementation, which can have good resolution when it's backed by fast
    enough timing hardware, as in this example:
 
-<screen>
+<screen><![CDATA[
 $ cat /sys/devices/system/clocksource/clocksource0/available_clocksource
 jiffies
 $ dmesg | grep time.c
@@ -218,7 +218,7 @@ Histogram of timing durations:
      8      0.00007         22
     16      0.00000          1
     32      0.00000          1
-</screen></para>
+]]></screen></para>
 
  </refsect2>
 

doc/src/sgml/release-8.4.sgml

@@ -962,7 +962,7 @@
       to fix all pre-existing data errors.  However, an installation can be
       presumed safe after performing this vacuuming if it has executed fewer
       than 2^31 update transactions in its lifetime (check this with
-      <literal>SELECT txid_current() < 2^31</>).
+      <literal>SELECT txid_current() &lt; 2^31</>).
      </para>
     </listitem>
 

doc/src/sgml/release-9.0.sgml

@@ -2900,7 +2900,7 @@
       to fix all pre-existing data errors.  However, an installation can be
       presumed safe after performing this vacuuming if it has executed fewer
       than 2^31 update transactions in its lifetime (check this with
-      <literal>SELECT txid_current() < 2^31</>).
+      <literal>SELECT txid_current() &lt; 2^31</>).
      </para>
     </listitem>
 

doc/src/sgml/release-9.1.sgml

@@ -4654,7 +4654,7 @@ Branch: REL9_0_STABLE [9d6af7367] 2015-08-15 11:02:34 -0400
       to fix all pre-existing data errors.  However, an installation can be
       presumed safe after performing this vacuuming if it has executed fewer
       than 2^31 update transactions in its lifetime (check this with
-      <literal>SELECT txid_current() < 2^31</>).
+      <literal>SELECT txid_current() &lt; 2^31</>).
      </para>
     </listitem>
 

doc/src/sgml/release-9.2.sgml

@@ -6553,7 +6553,7 @@ Branch: REL9_2_STABLE [6b700301c] 2015-02-17 16:03:00 +0100
       to fix all pre-existing data errors.  However, an installation can be
       presumed safe after performing this vacuuming if it has executed fewer
       than 2^31 update transactions in its lifetime (check this with
-      <literal>SELECT txid_current() < 2^31</>).
+      <literal>SELECT txid_current() &lt; 2^31</>).
      </para>
     </listitem>
 

doc/src/sgml/release-9.3.sgml

@@ -9930,7 +9930,7 @@ Branch: REL8_4_STABLE [c0c2d62ac] 2014-02-14 21:59:56 -0500
       to fix all pre-existing data errors.  However, an installation can be
       presumed safe after performing this vacuuming if it has executed fewer
       than 2^31 update transactions in its lifetime (check this with
-      <literal>SELECT txid_current() < 2^31</>).
+      <literal>SELECT txid_current() &lt; 2^31</>).
      </para>
     </listitem>
 

doc/src/sgml/rules.sgml

@@ -970,7 +970,7 @@ CREATE MATERIALIZED VIEW sales_summary AS
       invoice_date,
       sum(invoice_amt)::numeric(13,2) as sales_amt
     FROM invoice
-    WHERE invoice_date < CURRENT_DATE
+    WHERE invoice_date &lt; CURRENT_DATE
     GROUP BY
       seller_no,
       invoice_date
@@ -1058,7 +1058,7 @@ SELECT count(*) FROM words WHERE word = 'caterpiler';
     have wanted.  Again using <literal>file_fdw</literal>:
 
 <programlisting>
-SELECT word FROM words ORDER BY word <-> 'caterpiler' LIMIT 10;
+SELECT word FROM words ORDER BY word &lt;-&gt; 'caterpiler' LIMIT 10;
 
      word     
 ---------------

doc/src/sgml/syntax.sgml

@@ -1725,7 +1725,7 @@ SELECT percentile_cont(0.5) WITHIN GROUP (ORDER BY income) FROM households;
 <programlisting>
 SELECT
     count(*) AS unfiltered,
-    count(*) FILTER (WHERE i < 5) AS filtered
+    count(*) FILTER (WHERE i &lt; 5) AS filtered
 FROM generate_series(1,10) AS s(i);
  unfiltered | filtered
 ------------+----------