Make mutt.texi and mutt.info generation continue on failure.

Add warning messages, noting the appropriate packages to install.

Note: mutt.texi won't normally be built unless configure finds one of
the possible expected conversion program names.  Unfortunately, the
canonical name, "docbook2texi", is used by both the docbook2x and
docbook-utils projects.

So on Arch, the canonical name is what we need, while on Debian and
Red Hat/Fedora it isn't.  We search for the alternative names first,
but it's still possible to invoke the wrong program if the needed
package is not installed.

diff --git a/doc/Makefile.am b/doc/Makefile.am
index da07c66f79bebf4afb72cb99e03bea165b5dd68e..e6361acf8a9ef0b1dd6130bfa6778f16ab0305cc 100644 (file)
--- a/doc/Makefile.am
+++ b/doc/Makefile.am
@@ -161,14 +161,21 @@ manual.tex: stamp-doc-xml
        fi
 
 mutt.texi: stamp-doc-xml
-       $(DB2XTEXI) --encoding=utf-8 \
+       -$(DB2XTEXI) --encoding=utf-8 \
            --string-param output-file=mutt \
            --string-param 'directory-category=Email-software' \
            --string-param 'directory-description=Text based mail reader' \
            manual.xml
+       @-if test ! -f mutt.texi; then \
+         echo "WARNING: mutt.texi generation failed!"; \
+         echo "To generate Gnu Info documentation, install docbook2x."; \
+         echo "On Debian based systems, this is the 'docbook2x' package."; \
+         echo "On Red Hat/Fedora systems, this is the 'docbook2X' package."; \
+         echo "After installing the package, please re-run configure."; \
+       fi
 
 mutt.info: mutt.texi
-       $(MAKEINFO) --no-split -o mutt.info mutt.texi
+       -$(MAKEINFO) --no-split -o mutt.info mutt.texi
 
 validate: stamp-doc-xml
        xmllint --noout --noblanks --postvalid manual.xml