Some attempt at incremental build, but it actually makes it slower

It seems that the bottleneck is just looping over all these files...

Moreover, we need to remove files that are no longer wanted from
the target, so cleaning the target directory is necessary for now.

1 files changed, 237 insertions, 0 deletions

diff --git a/utils/build-incremental.sh b/utils/build-incremental.sh
new file mode 100755
index 0000000..5c6d74c
--- /dev/null
+++ b/utils/build-incremental.sh
@@ -0,0 +1,237 @@
+#!/bin/sh
+
+basedir="$(pwd)"
+
+if [ "$(uname)" = "Linux" ]; then
+        date_last_modified_cmd="stat -c %Y"
+else
+        date_last_modified_cmd="stat -f %m"
+fi
+
+age_top="$($date_last_modified_cmd top.html)"
+age_top_nobar="$($date_last_modified_cmd top-nobar.html)"
+age_bottom="$($date_last_modified_cmd bottom.html)"
+
+recursivebuild() {
+        local destdir=$(echo "$1" | sed 's|^src|http|')
+        mkdir -p "$destdir"
+        for file in "$1"/*; do
+                if [ -d "$file" ]; then
+                        mkdir -p "$destdir/$(basename "$file")"
+                        recursivebuild "$file"
+                else
+                        copyfile "$file" "$destdir"
+                fi
+        done
+}
+
+# This function is currently useless, but we keep it in case we need to
+# preprocess some m4 files.
+mdpreprocess() {
+        file="$1"
+        if [ "$(echo "$file" | sed 's/.*\.//')" = "m4" ]; then
+                printf 'm4_include(macros.m4)m4_dnl\n%s\n' "$(cat "$file")" | \
+                        m4 -P -I "$basedir/utils"
+        else
+                cat "$file"
+        fi
+}
+
+copyfile() {
+        file=$1
+        dest=$2
+        ind=$dest/index.html
+        extension=$(echo "$file" | sed 's/.*\.//')
+        age_src="$($date_last_modified_cmd "$file")"
+
+        case "$extension" in
+        # m4 preprocess is currently disabled
+        #m4)
+        #       noext=$(echo "$file" | sed 's/\..*//')
+        #       mdpreprocess "$file" > $noext.md
+        #       ;;
+        md)
+                if [ \( -f "$ind" \) ]; then
+                        age_dst="$($date_last_modified_cmd "$ind")"
+                        if [ \( "$age_dst" -ge "$age_src" \) -a \
+                             \( "$age_dst" -ge "$age_top" \) -a \
+                             \( "$age_dst" -ge "$age_bottom" \) ]; then
+                                echo "Skipping "$file" -> "$ind""
+                                return
+                        fi
+                fi
+
+                echo "Building "$file" -> "$ind""
+
+                t="$(markdowntitle "$file")"
+                sed "s/TITLE/$t/" < top.html > "$ind"
+                mdpreprocess "$file" | \
+                        lowdown --html-no-skiphtml --html-no-escapehtml \
+                        >> "$ind"
+                cat bottom.html >> "$ind"
+                ;;
+        noheadermd)
+                if [ \( -f "$ind" \) ]; then
+                        age_dst="$($date_last_modified_cmd "$ind")"
+                        if [ \( "$age_dst" -ge "$age_src" \) -a \
+                             \( "$age_dst" -ge "$age_top_nobar" \) -a \
+                             \( "$age_dst" -ge "$age_bottom" \) ]; then
+                                echo "Skipping "$file" -> "$ind""
+                                return
+                        fi
+                fi
+
+                echo "Building "$file" -> "$ind""
+
+                t="$(markdowntitle "$file")"
+                sed "s/TITLE/$t/" < top-nobar.html > "$ind"
+                mdpreprocess "$file" | \
+                        lowdown --html-no-skiphtml --html-no-escapehtml \
+                        >> "$ind"
+                ;;
+        html)
+                if [ \( -f "$ind" \) ]; then
+                        age_dst="$($date_last_modified_cmd "$ind")"
+                        if [ \( "$age_dst" -ge "$age_src" \) -a \
+                             \( "$age_dst" -ge "$age_top" \) -a \
+                             \( "$age_dst" -ge "$age_bottom" \) ]; then
+                                echo "Skipping "$file" -> "$ind""
+                                return
+                        fi
+                fi
+
+                echo "Copying "$file" -> "$ind""
+
+                t="$(htmltitle "$file")"
+                cat top.html "$file" bottom.html | sed "s/TITLE/$t/" > "$ind"
+                ;;
+        raw)
+                namenoraw="$(basename "$file" | sed 's/\.raw$//')"
+                if [ \( -f "$dest/$namenoraw" \) ]; then
+                        age_dst="$($date_last_modified_cmd "$dest/$namenoraw")"
+                        if [ "$age_dst" -ge "$age_src" ]; then
+                                echo "Skipping "$file" -> "$dest/$namenoraw""
+                                return
+                        fi
+                fi
+
+                echo "Copying "$file" -> "$dest/$namenoraw""
+
+                cp "$file" "$dest/$namenoraw"
+                ;;
+        *)
+                dest_name="$(basename "$file")"
+                if [ \( -f "$dest/$dest_name" \) ]; then
+                        age_dst="$($date_last_modified_cmd "$dest/$dest_name")"
+                        if [ "$age_dst" -ge "$age_src" ]; then
+                                echo "Skipping "$file" -> "$dest/$dest_name""
+                                return
+                        fi
+                fi
+
+                echo "Copying "$file" -> "$dest/$dest_name""
+
+                cp "$file" "$dest/$dest_name"
+        esac
+}
+
+markdowntitle() {
+        grep '^# ' "$1" | head -n 1 | sed 's/^# //'
+}
+
+htmltitle() {
+        grep '<!--TITLE: ' "$1" | sed 's/^<!--TITLE: //' | sed 's/-->$//'
+}
+
+makeblogindexandfeed() {
+        mkdir -p http/blog
+        bf=http/blog/index.html
+        ff=http/blog/feed.xml
+
+        sed "s/TITLE/Blog/" < top.html > "$bf"
+        { echo '<h1 id="blog">Blog</h1>';
+          echo '<table id="blog">';
+          echo '<a href="../series">Blog series</a> - ';
+          echo '<a href="feed.xml">RSS feed</a>'; } >> "$bf"
+
+        cp feed-top.xml "$ff"
+
+        for i in $(ls src/blog | sort -r); do
+                [ -d "src/blog/$i" ] || continue
+
+                f="src/blog/$i/*.md"
+                d="$(echo "$i" | grep -oE '^[0-9]{4}-[0-9]{2}-[0-9]{2}')"
+                t="$(markdowntitle $f)"
+                link="https://sebastiano.tronto.net/blog/$i"
+
+                thisyear="$(echo "$d" | sed 's/-.*//')"
+                if [ "$thisyear" != "$lastyear" ]; then
+                        echo "<tr><td><h2>$thisyear</h2></td></tr>" >> "$bf"
+                        lastyear=$thisyear
+                fi
+
+                { echo "<tr><td>$d</td>";
+                  echo "<td><a href=\"$i\">$t</a></td></tr>"; } >> "$bf"
+
+                dd="$(echo "$d" | sed 's/.*-//')"
+                mm="$(echo "$d" | sed 's/....-//' | sed 's/-.*//')"
+                mon="$(month "$mm")"
+                { echo "<item>";
+                  echo "<title>$t</title>";
+                  echo "<link>$link</link>";
+                  echo "<guid isPermaLink=\"true\">$link</guid>";
+                  echo "<description>$t</description>";
+                  echo "<pubDate>$dd $mon $thisyear 00:00:00 GMT</pubDate>";
+                  echo "</item>";
+                  echo ""; } >> $ff
+        done
+
+        echo '</table>' >> "$bf"
+        cat bottom.html >> "$bf"
+
+        { echo ""; echo "</channel>"; echo "</rss>"; } >> "$ff"
+}
+
+month() {
+        case "$1" in
+        01)
+                echo "Jan"
+                ;;
+        02)
+                echo "Feb"
+                ;;
+        03)
+                echo "Mar"
+                ;;
+        04)
+                echo "Apr"
+                ;;
+        05)
+                echo "May"
+                ;;
+        06)
+                echo "Jun"
+                ;;
+        07)
+                echo "Jul"
+                ;;
+        08)
+                echo "Aug"
+                ;;
+        09)
+                echo "Sep"
+                ;;
+        10)
+                echo "Oct"
+                ;;
+        11)
+                echo "Nov"
+                ;;
+        12)
+                echo "Dec"
+                ;;
+        esac
+}
+
+makeblogindexandfeed
+recursivebuild src