[PATCH v2 06/18] website: properly handle the dot dependency.

[Denis 'GNUtoo' Carikli]

This was broken by the commit 388c0ef3d09623dd10a4f44f8f610244c3337e4c
("website: add history page of the GNU Boot git repositories.").

Signed-off-by: Denis 'GNUtoo' Carikli <GNUtoo@cyberdimension.org>
Acked-by: Adrien Bourmault <neox@gnu.org>
---
ChangeLog v1->v2:
- Added neox's ack.
---
 website/Makefile.am  | 13 +++++++++++++
 website/configure.ac |  5 +++++
 2 files changed, 18 insertions(+)

diff --git a/website/Makefile.am b/website/Makefile.am
index 1153f92e..c45ec1ce 100644
--- a/website/Makefile.am
+++ b/website/Makefile.am
@@ -27,8 +27,21 @@ endif
 index.html: index.html.tmpl
        sed -e "s#WEBSITE_PREFIX#$(WEBSITE_PREFIX)#g" "$^" > "$@"
 
+if WANT_GUIX
 history/git-history.jpg: history/git-history.dot
+       guix time-machine \
+       --commit=$(GUIX_REVISION) \
+       -- \
+       shell \
+               --system=i686-linux \
+               --container \
+               graphviz \
+       -- \
        dot -T jpg history/git-history.dot > "$@"
+else
+history/git-history.jpg: history/git-history.dot
+       dot -T jpg history/git-history.dot > "$@"
+endif
 
 # We need force the regeneration of the page because if only the git
 # commit changes, there is no way to know about it. In addition the
diff --git a/website/configure.ac b/website/configure.ac
index b3cd6182..9749051b 100644
--- a/website/configure.ac
+++ b/website/configure.ac
@@ -130,6 +130,11 @@ AS_IF([test x"$guix" = x"yes"],
              [AC_MSG_ERROR(
               [date was not found in PATH ($PATH)])])
 
+       AC_CHECK_PROG([FOUND_DOT], [dot], [dot])
+       AS_IF([test x"$FOUND_DOT" = x""],
+             [AC_MSG_ERROR(
+              [dot was not found in PATH ($PATH)])])
+
        AC_CHECK_PROG([FOUND_FIND], [find], [find])
        AS_IF([test x"$FOUND_FIND" = x""],
              [AC_MSG_ERROR(
-- 
2.34.1