diff: parse separate options like -S foo

Change the option parsing logic in revision.c to accept separate forms
like `-S foo' in addition to `-Sfoo'. The rest of git already accepted
this form, but revision.c still used its own option parsing.

Short options affected are -S<string>, -l<num> and -O<orderfile>, for
which an empty string wouldn't make sense, hence -<option> <arg> isn't
ambiguous.

This patch does not handle --stat-name-width and --stat-width, which are
special-cases where diff_long_opt do not apply. They are handled in a
separate patch to ease review.

Original patch by Matthieu Moy, plus refactoring by Jonathan Nieder.

Signed-off-by: Matthieu Moy <Matthieu.Moy@imag.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 7 insertions, 0 deletions

diff --git a/diff.h b/diff.h
index 063d10ac2..2b94ad66d 100644
--- a/diff.h
+++ b/diff.h
@@ -214,6 +214,13 @@ extern void diff_unmerge(struct diff_options *,
 #define DIFF_SETUP_USE_CACHE		2
 #define DIFF_SETUP_USE_SIZE_CACHE	4
 
+/*
+ * Poor man's alternative to parse-option, to allow both sticked form
+ * (--option=value) and separate form (--option value).
+ */
+extern int parse_long_opt(const char *opt, const char **argv,
+			 const char **optarg);
+
 extern int git_diff_basic_config(const char *var, const char *value, void *cb);
 extern int git_diff_ui_config(const char *var, const char *value, void *cb);
 extern int diff_use_color_default;