1#!/bin/sh
2# git-difftool--helper is a GIT_EXTERNAL_DIFF-compatible diff tool launcher.
3# This script is typically launched by using the 'git difftool'
4# convenience command.
5#
6# Copyright (c) 2009, 2010 David Aguilar
7
8TOOL_MODE=diff
9. git-mergetool--lib
10
11# difftool.prompt controls the default prompt/no-prompt behavior
12# and is overridden with $GIT_DIFFTOOL*_PROMPT.
13should_prompt () {
14	prompt_merge=$(git config --bool mergetool.prompt || echo true)
15	prompt=$(git config --bool difftool.prompt || echo $prompt_merge)
16	if test "$prompt" = true
17	then
18		test -z "$GIT_DIFFTOOL_NO_PROMPT"
19	else
20		test -n "$GIT_DIFFTOOL_PROMPT"
21	fi
22}
23
24# Indicates that --extcmd=... was specified
25use_ext_cmd () {
26	test -n "$GIT_DIFFTOOL_EXTCMD"
27}
28
29launch_merge_tool () {
30	# Merged is the filename as it appears in the work tree
31	# Local is the contents of a/filename
32	# Remote is the contents of b/filename
33	# Custom merge tool commands might use $BASE so we provide it
34	MERGED="$1"
35	LOCAL="$2"
36	REMOTE="$3"
37	BASE="$1"
38
39	# $LOCAL and $REMOTE are temporary files so prompt
40	# the user with the real $MERGED name before launching $merge_tool.
41	if should_prompt
42	then
43		printf "\nViewing (%s/%s): '%s'\n" "$GIT_DIFF_PATH_COUNTER" \
44			"$GIT_DIFF_PATH_TOTAL" "$MERGED"
45		if use_ext_cmd
46		then
47			printf "Launch '%s' [Y/n]? " \
48				"$GIT_DIFFTOOL_EXTCMD"
49		else
50			printf "Launch '%s' [Y/n]? " "$merge_tool"
51		fi
52		read ans || return
53		if test "$ans" = n
54		then
55			return
56		fi
57	fi
58
59	if use_ext_cmd
60	then
61		export BASE
62		eval $GIT_DIFFTOOL_EXTCMD '"$LOCAL"' '"$REMOTE"'
63	else
64		initialize_merge_tool "$merge_tool"
65		# ignore the error from the above --- run_merge_tool
66		# will diagnose unusable tool by itself
67		run_merge_tool "$merge_tool"
68	fi
69}
70
71if ! use_ext_cmd
72then
73	if test -n "$GIT_DIFF_TOOL"
74	then
75		merge_tool="$GIT_DIFF_TOOL"
76	else
77		merge_tool="$(get_merge_tool)"
78	fi
79fi
80
81if test -n "$GIT_DIFFTOOL_DIRDIFF"
82then
83	LOCAL="$1"
84	REMOTE="$2"
85	initialize_merge_tool "$merge_tool"
86	# ignore the error from the above --- run_merge_tool
87	# will diagnose unusable tool by itself
88	run_merge_tool "$merge_tool" false
89else
90	# Launch the merge tool on each path provided by 'git diff'
91	while test $# -gt 6
92	do
93		launch_merge_tool "$1" "$2" "$5"
94		status=$?
95		if test $status -ge 126
96		then
97			# Command not found (127), not executable (126) or
98			# exited via a signal (>= 128).
99			exit $status
100		fi
101
102		if test "$status" != 0 &&
103			test "$GIT_DIFFTOOL_TRUST_EXIT_CODE" = true
104		then
105			exit $status
106		fi
107		shift 7
108	done
109fi
110
111exit 0
112