RFC patchgit-help: add new options -w (for web) and -i (for info)

Documentation/Makefile, Makefile, git-html-help.sh, help.c

diff --git a/Documentation/Makefile b/Documentation/Makefile
index d886641..3e01718 100644
--- a/Documentation/Makefile
+++ b/Documentation/Makefile
@@ -29,6 +29,7 @@ DOC_MAN7=$(patsubst %.txt,%.7,$(MAN7_TXT))
 
 prefix?=$(HOME)
 bindir?=$(prefix)/bin
+htmldir?=$(prefix)/share/doc/git-doc
 mandir?=$(prefix)/share/man
 man1dir=$(mandir)/man1
 man5dir=$(mandir)/man5
@@ -95,6 +96,9 @@ install-info: info
 	  echo "No directory found in $(DESTDIR)$(infodir)" >&2 ; \
 	fi
 
+install-html: html
+	sh ./install-webdoc.sh $(htmldir)
+
 ../GIT-VERSION-FILE: .FORCE-GIT-VERSION-FILE
 	$(MAKE) -C ../ GIT-VERSION-FILE
 
diff --git a/Makefile b/Makefile
index 313f9a2..6ccf7e7 100644
--- a/Makefile
+++ b/Makefile
@@ -223,7 +223,8 @@ SCRIPT_SH = \
 	git-merge-resolve.sh \
 	git-lost-found.sh git-quiltimport.sh git-submodule.sh \
 	git-filter-branch.sh \
-	git-stash.sh
+	git-stash.sh \
+	git-html-help.sh
 
 SCRIPT_PERL = \
 	git-add--interactive.perl \
@@ -807,6 +808,7 @@ $(patsubst %.sh,%,$(SCRIPT_SH)) : % : %.sh
 	    -e 's|@@PERL@@|$(PERL_PATH_SQ)|g' \
 	    -e 's/@@GIT_VERSION@@/$(GIT_VERSION)/g' \
 	    -e 's/@@NO_CURL@@/$(NO_CURL)/g' \
+	    -e 's|@@PREFIX@@|$(prefix_SQ)|g' \
 	    $@.sh >$@+ && \
 	chmod +x $@+ && \
 	mv $@+ $@
diff --git a/git-html-help.sh b/git-html-help.sh
new file mode 100755
index 0000000..286d3b5
--- /dev/null
+++ b/git-html-help.sh
@@ -0,0 +1,125 @@
+#!/bin/sh
+#
+# This program launch a web browser on the html page
+# describing a git command.
+#
+# Copyright (c) 2007 Christian Couder
+# Copyright (c) 2006 Theodore Y. Ts'o
+#
+# This file is heavily stolen from git-mergetool.sh, by
+# Theodore Y. Ts'o (thanks) that is:
+#
+# Copyright (c) 2006 Theodore Y. Ts'o
+#
+# This file is licensed under the GPL v2, or a later version
+# at the discretion of Junio C Hamano or any other official
+# git maintainer.
+#
+
+USAGE='[--tool=tool] [cmd to display] ...'
+SUBDIRECTORY_OK=Yes
+OPTIONS_SPEC=
+. git-sh-setup
+
+valid_tool() {
+	case "$1" in
+		firefox | iceweasel | konqueror | w3m)
+			;; # happy
+		*)
+			return 1
+			;;
+	esac
+}
+
+init_browser_path() {
+	browser_path=`git config webtool.$1.path`
+	test -z "$browser_path" && browser_path=$1
+}
+
+while test $# != 0
+do
+    case "$1" in
+	-t|--tool*)
+	    case "$#,$1" in
+		*,*=*)
+		    browser=`expr "z$1" : 'z-[^=]*=\(.*\)'`
+		    ;;
+		1,*)
+		    usage ;;
+		*)
+		    browser="$2"
+		    shift ;;
+	    esac
+	    ;;
+	--)
+	    break
+	    ;;
+	-*)
+	    usage
+	    ;;
+	*)
+	    break
+	    ;;
+    esac
+    shift
+done
+
+if test -z "$browser"; then
+    browser=`git config web.tool`
+    if test -n "$browser" && ! valid_tool "$browser"; then
+	    echo >&2 "git config option web.tool set to unknown tool: $browser"
+	    echo >&2 "Resetting to default..."
+	    unset browser
+    fi
+fi
+
+if test -z "$browser" ; then
+    if test -n "$DISPLAY"; then
+        browser_candidates="firefox iceweasel konqueror w3m"
+        if test "$KDE_FULL_SESSION" = "true"; then
+            browser_candidates="konqueror $browser_candidates"
+        fi
+    else
+        browser_candidates="w3m"
+    fi
+    echo "browser candidates: $browser_candidates"
+    for i in $browser_candidates; do
+        init_browser_path $i
+	echo "browser path: $browser_path"
+        if type "$browser_path" > /dev/null 2>&1; then
+            browser=$i
+            break
+        fi
+    done
+    test -z "$browser" && die "No known browser available."
+else
+    valid_tool "$browser" || die "Unknown browser $browser"
+
+    init_browser_path "$browser"
+
+    if ! type "$browser_path" > /dev/null 2>&1; then
+        die "The browser $browser is not available as '$browser_path'"
+    fi
+fi
+
+html_dir="@@PREFIX@@/share/doc/git-doc"
+pages=$(for p in "$@"; do echo "$html_dir/$p.html" ; done)
+test -z "$pages" && pages="$html_dir/git.html"
+
+case "$browser" in
+    firefox|iceweasel)
+        # TODO check version (firefox < 2.0 does not support -new-tab)
+        nohup "$browser" -new-tab $pages &
+	;;
+    konqueror)
+        # FIXME: we may want to find an existing konqueror and use
+        # dcop to tell it what to do.
+        nohup "$browser" $pages &
+        ;;
+    w3m)
+        eval "$browser" $pages
+        ;;
+esac
+
+
+
diff --git a/help.c b/help.c
index 37a9c25..a5602a2 100644
--- a/help.c
+++ b/help.c
@@ -239,24 +239,38 @@ void list_common_cmds_help(void)
 	}
 }
 
-static void show_man_page(const char *git_cmd)
+static const char *cmd_to_page(const char *git_cmd)
 {
-	const char *page;
-
 	if (!prefixcmp(git_cmd, "git"))
-		page = git_cmd;
+		return git_cmd;
 	else {
 		int page_len = strlen(git_cmd) + 4;
 		char *p = xmalloc(page_len + 1);
 		strcpy(p, "git-");
 		strcpy(p + 4, git_cmd);
 		p[page_len] = 0;
-		page = p;
+		return p;
 	}
+}
 
+static void show_man_page(const char *git_cmd)
+{
+	const char *page = cmd_to_page(git_cmd);
 	execlp("man", "man", page, NULL);
 }
 
+static void show_info_page(const char *git_cmd)
+{
+	const char *page = cmd_to_page(git_cmd);
+	execlp("info", "info", page, NULL);
+}
+
+static void show_html_page(const char *git_cmd)
+{
+	const char *page = cmd_to_page(git_cmd);
+	execlp("git-html-help", "git-html-help", page, NULL);
+}
+
 void help_unknown_cmd(const char *cmd)
 {
 	fprintf(stderr, "git: '%s' is not a git-command. See 'git --help'.\n", cmd);
@@ -269,10 +283,8 @@ int cmd_version(int argc, const char **argv, const char *prefix)
 	return 0;
 }
 
-int cmd_help(int argc, const char **argv, const char *prefix)
+static void check_help_cmd(const char *help_cmd)
 {
-	const char *help_cmd = argc > 1 ? argv[1] : NULL;
-
 	if (!help_cmd) {
 		printf("usage: %s\n\n", git_usage_string);
 		list_common_cmds_help();
@@ -284,6 +296,26 @@ int cmd_help(int argc, const char **argv, const char *prefix)
 		list_commands();
 		exit(0);
 	}
+}
+
+int cmd_help(int argc, const char **argv, const char *prefix)
+{
+	const char *help_cmd = argc > 1 ? argv[1] : NULL;
+	check_help_cmd(help_cmd);
+
+	if (!strcmp(help_cmd, "--web") || !strcmp(help_cmd, "-w")) {
+		help_cmd = argc > 2 ? argv[2] : NULL;
+		check_help_cmd(help_cmd);
+
+		show_html_page(help_cmd);
+	}
+
+	else if (!strcmp(help_cmd, "--info") || !strcmp(help_cmd, "-i")) {
+		help_cmd = argc > 2 ? argv[2] : NULL;
+		check_help_cmd(help_cmd);
+
+		show_info_page(help_cmd);
+	}
 
 	else
 		show_man_page(help_cmd);