1#!/bin/sh23OPTIONS_SPEC="\4doc-diff [options] <from> <to> [-- <diff-options>]5--6j=n parallel argument to pass to make7f force rebuild; do not rely on cached results8"9SUBDIRECTORY_OK=110. "$(git --exec-path)/git-sh-setup"1112parallel=13force=14while test $# -gt 015do16case "$1" in17-j)18parallel=$2; shift ;;19-f)20force=t ;;21--)22shift; break ;;23*)24usage ;;25esac26shift27done2829if test -z "$parallel"30then31parallel=$(getconf _NPROCESSORS_ONLN 2>/dev/null)32if test $? != 0 || test -z "$parallel"33then34parallel=135fi36fi3738test $# -gt 1 || usage39from=$1; shift40to=$1; shift4142from_oid=$(git rev-parse --verify "$from") || exit 143to_oid=$(git rev-parse --verify "$to") || exit 14445cd_to_toplevel46tmp=Documentation/tmp-doc-diff4748if test -n "$force"49then50rm -rf "$tmp"51fi5253# We'll do both builds in a single worktree, which lets "make" reuse54# results that don't differ between the two trees.55if ! test -d "$tmp/worktree"56then57git worktree add --detach "$tmp/worktree" "$from" &&58dots=$(echo "$tmp/worktree" | sed 's#[^/]*#..#g') &&59ln -s "$dots/config.mak" "$tmp/worktree/config.mak"60fi6162# generate_render_makefile <srcdir> <dstdir>63generate_render_makefile () {64find "$1" -type f |65while read src66do67dst=$2/${src#$1/}68printf 'all:: %s\n' "$dst"69printf '%s: %s\n' "$dst" "$src"70printf '\t@echo >&2 " RENDER $(notdir $@)" && \\\n'71printf '\tmkdir -p $(dir $@) && \\\n'72printf '\tMANWIDTH=80 man -l $< >$@+ && \\\n'73printf '\tmv $@+ $@\n'74done75}7677# render_tree <dirname> <committish>78render_tree () {79# Skip install-man entirely if we already have an installed directory.80# We can't rely on make here, since "install-man" unconditionally81# copies the files (spending effort, but also updating timestamps that82# we then can't rely on during the render step). We use "mv" to make83# sure we don't get confused by a previous run that failed partway84# through.85if ! test -d "$tmp/installed/$1"86then87git -C "$tmp/worktree" checkout "$2" &&88make -j$parallel -C "$tmp/worktree" \89GIT_VERSION=omitted \90SOURCE_DATE_EPOCH=0 \91DESTDIR="$PWD/$tmp/installed/$1+" \92install-man &&93mv "$tmp/installed/$1+" "$tmp/installed/$1"94fi &&9596# As with "installed" above, we skip the render if it's already been97# done. So using make here is primarily just about running in98# parallel.99if ! test -d "$tmp/rendered/$1"100then101generate_render_makefile "$tmp/installed/$1" "$tmp/rendered/$1+" |102make -j$parallel -f - &&103mv "$tmp/rendered/$1+" "$tmp/rendered/$1"104fi105}106107render_tree $from_oid "$from" &&108render_tree $to_oid "$to" &&109git -C $tmp/rendered diff --no-index "$@" $from_oid $to_oid