meson: Document build targets, add 'help' target

Currently important build targets are somewhat hard to discover. This commit
documents important meson build targets in the sgml documentation. But it's
awkward to have to lookup build targets in the docs when hacking, so this also
adds a 'help' target, printing out the same information. To avoid having to
duplicate information in two places, generate both docbook and interactive
docs from a single source.

Reviewed-by: Peter Eisentraut <[email protected]>
Discussion: https://postgr.es/m/[email protected]

1 files changed, 6 insertions, 7 deletions

diff --git a/doc/src/sgml/docguide.sgml b/doc/src/sgml/docguide.sgml
index b319621fdb8..c129215dd3c 100644
--- a/doc/src/sgml/docguide.sgml
+++ b/doc/src/sgml/docguide.sgml
@@ -434,9 +434,9 @@ LOGLEVEL=-Dorg.apache.commons.logging.simplelog.defaultlog=WARN
   <title>Building the Documentation with Meson</title>
 
    <para>
-    Two options are provided for building the documentation using Meson.
-    Change to the <filename>build</filename> directory before running
-    one of these commands, or add <option>-C build</option> to the command.
+    To build the documentation using Meson, change to the
+    <filename>build</filename> directory before running one of these commands,
+    or add <option>-C build</option> to the command.
    </para>
 
    <para>
@@ -444,10 +444,9 @@ LOGLEVEL=-Dorg.apache.commons.logging.simplelog.defaultlog=WARN
 <screen>
 <prompt>build$ </prompt><userinput>ninja html</userinput>
 </screen>
-    To build all forms of the documentation:
-<screen>
-<prompt>build$ </prompt><userinput>ninja alldocs</userinput>
-</screen>
+    For a list of other documentation targets see
+    <xref linkend="targets-meson-documentation"/>.
+
     The output appears in the
     subdirectory <filename>build/doc/src/sgml</filename>.
    </para>