contrib/completion: add smerge to the mergetool completion candidates
[gitweb.git] / diff.c
diff --git a/diff.c b/diff.c
index e3f263769b4272e4330e5d5e8fbeaacee20a6db4..ec5c095199b3953cc74dabdfccf4536d4c6df831 100644 (file)
--- a/diff.c
+++ b/diff.c
@@ -23,6 +23,7 @@
 #include "argv-array.h"
 #include "graph.h"
 #include "packfile.h"
+#include "parse-options.h"
 #include "help.h"
 
 #ifdef NO_FAST_WORKING_DIRECTORY
@@ -103,11 +104,6 @@ static const char *color_diff_slots[] = {
        [DIFF_FILE_NEW_BOLD]          = "newBold",
 };
 
-static NORETURN void die_want_option(const char *option_name)
-{
-       die(_("option '%s' requires a value"), option_name);
-}
-
 define_list_config_array_extra(color_diff_slots, {"plain"});
 
 static int parse_diff_color_slot(const char *var)
@@ -178,6 +174,10 @@ static int parse_submodule_params(struct diff_options *options, const char *valu
                options->submodule_format = DIFF_SUBMODULE_SHORT;
        else if (!strcmp(value, "diff"))
                options->submodule_format = DIFF_SUBMODULE_INLINE_DIFF;
+       /*
+        * Please update $__git_diff_submodule_formats in
+        * git-completion.bash when you add new formats.
+        */
        else
                return -1;
        return 0;
@@ -204,6 +204,10 @@ long parse_algorithm_value(const char *value)
                return XDF_PATIENCE_DIFF;
        else if (!strcasecmp(value, "histogram"))
                return XDF_HISTOGRAM_DIFF;
+       /*
+        * Please update $__git_diff_algorithms in git-completion.bash
+        * when you add new algorithms.
+        */
        return -1;
 }
 
@@ -4484,6 +4488,8 @@ static void run_checkdiff(struct diff_filepair *p, struct diff_options *o)
        builtin_checkdiff(name, other, attr_path, p->one, p->two, o);
 }
 
+static void prep_parse_options(struct diff_options *options);
+
 void repo_diff_setup(struct repository *r, struct diff_options *options)
 {
        memcpy(options, &default_diff_options, sizeof(*options));
@@ -4525,6 +4531,8 @@ void repo_diff_setup(struct repository *r, struct diff_options *options)
 
        options->color_moved = diff_color_moved_default;
        options->color_moved_ws_handling = diff_color_moved_ws_default;
+
+       prep_parse_options(options);
 }
 
 void diff_setup_done(struct diff_options *options)
@@ -4628,6 +4636,8 @@ void diff_setup_done(struct diff_options *options)
 
        if (!options->use_color || external_diff())
                options->color_moved = 0;
+
+       FREE_AND_NULL(options->parseopts);
 }
 
 static int opt_arg(const char *arg, int arg_short, const char *arg_long, int *val)
@@ -4674,8 +4684,6 @@ static int opt_arg(const char *arg, int arg_short, const char *arg_long, int *va
        return 1;
 }
 
-static int diff_scoreopt_parse(const char *opt);
-
 static inline int short_opt(char opt, const char **argv,
                            const char **optarg)
 {
@@ -4713,77 +4721,56 @@ int parse_long_opt(const char *opt, const char **argv,
        return 2;
 }
 
-static int stat_opt(struct diff_options *options, const char **av)
+static int diff_opt_stat(const struct option *opt, const char *value, int unset)
 {
-       const char *arg = av[0];
-       char *end;
+       struct diff_options *options = opt->value;
        int width = options->stat_width;
        int name_width = options->stat_name_width;
        int graph_width = options->stat_graph_width;
        int count = options->stat_count;
-       int argcount = 1;
+       char *end;
 
-       if (!skip_prefix(arg, "--stat", &arg))
-               BUG("stat option does not begin with --stat: %s", arg);
-       end = (char *)arg;
+       BUG_ON_OPT_NEG(unset);
 
-       switch (*arg) {
-       case '-':
-               if (skip_prefix(arg, "-width", &arg)) {
-                       if (*arg == '=')
-                               width = strtoul(arg + 1, &end, 10);
-                       else if (!*arg && !av[1])
-                               die_want_option("--stat-width");
-                       else if (!*arg) {
-                               width = strtoul(av[1], &end, 10);
-                               argcount = 2;
-                       }
-               } else if (skip_prefix(arg, "-name-width", &arg)) {
-                       if (*arg == '=')
-                               name_width = strtoul(arg + 1, &end, 10);
-                       else if (!*arg && !av[1])
-                               die_want_option("--stat-name-width");
-                       else if (!*arg) {
-                               name_width = strtoul(av[1], &end, 10);
-                               argcount = 2;
-                       }
-               } else if (skip_prefix(arg, "-graph-width", &arg)) {
-                       if (*arg == '=')
-                               graph_width = strtoul(arg + 1, &end, 10);
-                       else if (!*arg && !av[1])
-                               die_want_option("--stat-graph-width");
-                       else if (!*arg) {
-                               graph_width = strtoul(av[1], &end, 10);
-                               argcount = 2;
-                       }
-               } else if (skip_prefix(arg, "-count", &arg)) {
-                       if (*arg == '=')
-                               count = strtoul(arg + 1, &end, 10);
-                       else if (!*arg && !av[1])
-                               die_want_option("--stat-count");
-                       else if (!*arg) {
-                               count = strtoul(av[1], &end, 10);
-                               argcount = 2;
-                       }
+       if (!strcmp(opt->long_name, "stat")) {
+               if (value) {
+                       width = strtoul(value, &end, 10);
+                       if (*end == ',')
+                               name_width = strtoul(end+1, &end, 10);
+                       if (*end == ',')
+                               count = strtoul(end+1, &end, 10);
+                       if (*end)
+                               return error(_("invalid --stat value: %s"), value);
                }
-               break;
-       case '=':
-               width = strtoul(arg+1, &end, 10);
-               if (*end == ',')
-                       name_width = strtoul(end+1, &end, 10);
-               if (*end == ',')
-                       count = strtoul(end+1, &end, 10);
-       }
+       } else if (!strcmp(opt->long_name, "stat-width")) {
+               width = strtoul(value, &end, 10);
+               if (*end)
+                       return error(_("%s expects a numerical value"),
+                                    opt->long_name);
+       } else if (!strcmp(opt->long_name, "stat-name-width")) {
+               name_width = strtoul(value, &end, 10);
+               if (*end)
+                       return error(_("%s expects a numerical value"),
+                                    opt->long_name);
+       } else if (!strcmp(opt->long_name, "stat-graph-width")) {
+               graph_width = strtoul(value, &end, 10);
+               if (*end)
+                       return error(_("%s expects a numerical value"),
+                                    opt->long_name);
+       } else if (!strcmp(opt->long_name, "stat-count")) {
+               count = strtoul(value, &end, 10);
+               if (*end)
+                       return error(_("%s expects a numerical value"),
+                                    opt->long_name);
+       } else
+               BUG("%s should not get here", opt->long_name);
 
-       /* Important! This checks all the error cases! */
-       if (*end)
-               return 0;
        options->output_format |= DIFF_FORMAT_DIFFSTAT;
        options->stat_name_width = name_width;
        options->stat_graph_width = graph_width;
        options->stat_width = width;
        options->stat_count = count;
-       return argcount;
+       return 0;
 }
 
 static int parse_dirstat_opt(struct diff_options *options, const char *params)
@@ -4919,6 +4906,308 @@ static int parse_objfind_opt(struct diff_options *opt, const char *arg)
        return 1;
 }
 
+static int diff_opt_break_rewrites(const struct option *opt,
+                                  const char *arg, int unset)
+{
+       int *break_opt = opt->value;
+       int opt1, opt2;
+
+       BUG_ON_OPT_NEG(unset);
+       if (!arg)
+               arg = "";
+       opt1 = parse_rename_score(&arg);
+       if (*arg == 0)
+               opt2 = 0;
+       else if (*arg != '/')
+               return error(_("%s expects <n>/<m> form"), opt->long_name);
+       else {
+               arg++;
+               opt2 = parse_rename_score(&arg);
+       }
+       if (*arg != 0)
+               return error(_("%s expects <n>/<m> form"), opt->long_name);
+       *break_opt = opt1 | (opt2 << 16);
+       return 0;
+}
+
+static int diff_opt_char(const struct option *opt,
+                        const char *arg, int unset)
+{
+       char *value = opt->value;
+
+       BUG_ON_OPT_NEG(unset);
+       if (arg[1])
+               return error(_("%s expects a character, got '%s'"),
+                            opt->long_name, arg);
+       *value = arg[0];
+       return 0;
+}
+
+static int diff_opt_compact_summary(const struct option *opt,
+                                   const char *arg, int unset)
+{
+       struct diff_options *options = opt->value;
+
+       BUG_ON_OPT_ARG(arg);
+       if (unset) {
+               options->flags.stat_with_summary = 0;
+       } else {
+               options->flags.stat_with_summary = 1;
+               options->output_format |= DIFF_FORMAT_DIFFSTAT;
+       }
+       return 0;
+}
+
+static int diff_opt_dirstat(const struct option *opt,
+                           const char *arg, int unset)
+{
+       struct diff_options *options = opt->value;
+
+       BUG_ON_OPT_NEG(unset);
+       if (!strcmp(opt->long_name, "cumulative")) {
+               if (arg)
+                       BUG("how come --cumulative take a value?");
+               arg = "cumulative";
+       } else if (!strcmp(opt->long_name, "dirstat-by-file"))
+               parse_dirstat_opt(options, "files");
+       parse_dirstat_opt(options, arg ? arg : "");
+       return 0;
+}
+
+static int diff_opt_find_copies(const struct option *opt,
+                               const char *arg, int unset)
+{
+       struct diff_options *options = opt->value;
+
+       BUG_ON_OPT_NEG(unset);
+       if (!arg)
+               arg = "";
+       options->rename_score = parse_rename_score(&arg);
+       if (*arg != 0)
+               return error(_("invalid argument to %s"), opt->long_name);
+
+       if (options->detect_rename == DIFF_DETECT_COPY)
+               options->flags.find_copies_harder = 1;
+       else
+               options->detect_rename = DIFF_DETECT_COPY;
+
+       return 0;
+}
+
+static int diff_opt_find_renames(const struct option *opt,
+                                const char *arg, int unset)
+{
+       struct diff_options *options = opt->value;
+
+       BUG_ON_OPT_NEG(unset);
+       if (!arg)
+               arg = "";
+       options->rename_score = parse_rename_score(&arg);
+       if (*arg != 0)
+               return error(_("invalid argument to %s"), opt->long_name);
+
+       options->detect_rename = DIFF_DETECT_RENAME;
+       return 0;
+}
+
+static enum parse_opt_result diff_opt_output(struct parse_opt_ctx_t *ctx,
+                                            const struct option *opt,
+                                            const char *arg, int unset)
+{
+       struct diff_options *options = opt->value;
+       char *path;
+
+       BUG_ON_OPT_NEG(unset);
+       path = prefix_filename(ctx->prefix, arg);
+       options->file = xfopen(path, "w");
+       options->close_file = 1;
+       if (options->use_color != GIT_COLOR_ALWAYS)
+               options->use_color = GIT_COLOR_NEVER;
+       free(path);
+       return 0;
+}
+
+static int diff_opt_relative(const struct option *opt,
+                            const char *arg, int unset)
+{
+       struct diff_options *options = opt->value;
+
+       BUG_ON_OPT_NEG(unset);
+       options->flags.relative_name = 1;
+       if (arg)
+               options->prefix = arg;
+       return 0;
+}
+
+static int diff_opt_unified(const struct option *opt,
+                           const char *arg, int unset)
+{
+       struct diff_options *options = opt->value;
+       char *s;
+
+       BUG_ON_OPT_NEG(unset);
+
+       options->context = strtol(arg, &s, 10);
+       if (*s)
+               return error(_("%s expects a numerical value"), "--unified");
+       enable_patch_output(&options->output_format);
+
+       return 0;
+}
+
+static void prep_parse_options(struct diff_options *options)
+{
+       struct option parseopts[] = {
+               OPT_GROUP(N_("Diff output format options")),
+               OPT_BITOP('p', "patch", &options->output_format,
+                         N_("generate patch"),
+                         DIFF_FORMAT_PATCH, DIFF_FORMAT_NO_OUTPUT),
+               OPT_BIT_F('s', "no-patch", &options->output_format,
+                         N_("suppress diff output"),
+                         DIFF_FORMAT_NO_OUTPUT, PARSE_OPT_NONEG),
+               OPT_BITOP('u', NULL, &options->output_format,
+                         N_("generate patch"),
+                         DIFF_FORMAT_PATCH, DIFF_FORMAT_NO_OUTPUT),
+               OPT_CALLBACK_F('U', "unified", options, N_("<n>"),
+                              N_("generate diffs with <n> lines context"),
+                              PARSE_OPT_NONEG, diff_opt_unified),
+               OPT_BOOL('W', "function-context", &options->flags.funccontext,
+                        N_("generate diffs with <n> lines context")),
+               OPT_BIT_F(0, "raw", &options->output_format,
+                         N_("generate the diff in raw format"),
+                         DIFF_FORMAT_RAW, PARSE_OPT_NONEG),
+               OPT_BITOP(0, "patch-with-raw", &options->output_format,
+                         N_("synonym for '-p --raw'"),
+                         DIFF_FORMAT_PATCH | DIFF_FORMAT_RAW,
+                         DIFF_FORMAT_NO_OUTPUT),
+               OPT_BITOP(0, "patch-with-stat", &options->output_format,
+                         N_("synonym for '-p --stat'"),
+                         DIFF_FORMAT_PATCH | DIFF_FORMAT_DIFFSTAT,
+                         DIFF_FORMAT_NO_OUTPUT),
+               OPT_BIT_F(0, "numstat", &options->output_format,
+                         N_("machine friendly --stat"),
+                         DIFF_FORMAT_NUMSTAT, PARSE_OPT_NONEG),
+               OPT_BIT_F(0, "shortstat", &options->output_format,
+                         N_("output only the last line of --stat"),
+                         DIFF_FORMAT_SHORTSTAT, PARSE_OPT_NONEG),
+               OPT_CALLBACK_F('X', "dirstat", options, N_("<param1,param2>..."),
+                              N_("output the distribution of relative amount of changes for each sub-directory"),
+                              PARSE_OPT_NONEG | PARSE_OPT_OPTARG,
+                              diff_opt_dirstat),
+               OPT_CALLBACK_F(0, "cumulative", options, NULL,
+                              N_("synonym for --dirstat=cumulative"),
+                              PARSE_OPT_NONEG | PARSE_OPT_NOARG,
+                              diff_opt_dirstat),
+               OPT_CALLBACK_F(0, "dirstat-by-file", options, N_("<param1,param2>..."),
+                              N_("synonym for --dirstat=files,param1,param2..."),
+                              PARSE_OPT_NONEG | PARSE_OPT_OPTARG,
+                              diff_opt_dirstat),
+               OPT_BIT_F(0, "check", &options->output_format,
+                         N_("warn if changes introduce conflict markers or whitespace errors"),
+                         DIFF_FORMAT_CHECKDIFF, PARSE_OPT_NONEG),
+               OPT_BIT_F(0, "summary", &options->output_format,
+                         N_("condensed summary such as creations, renames and mode changes"),
+                         DIFF_FORMAT_SUMMARY, PARSE_OPT_NONEG),
+               OPT_BIT_F(0, "name-only", &options->output_format,
+                         N_("show only names of changed files"),
+                         DIFF_FORMAT_NAME, PARSE_OPT_NONEG),
+               OPT_BIT_F(0, "name-status", &options->output_format,
+                         N_("show only names and status of changed files"),
+                         DIFF_FORMAT_NAME_STATUS, PARSE_OPT_NONEG),
+               OPT_CALLBACK_F(0, "stat", options, N_("<width>[,<name-width>[,<count>]]"),
+                              N_("generate diffstat"),
+                              PARSE_OPT_NONEG | PARSE_OPT_OPTARG, diff_opt_stat),
+               OPT_CALLBACK_F(0, "stat-width", options, N_("<width>"),
+                              N_("generate diffstat with a given width"),
+                              PARSE_OPT_NONEG, diff_opt_stat),
+               OPT_CALLBACK_F(0, "stat-name-width", options, N_("<width>"),
+                              N_("generate diffstat with a given name width"),
+                              PARSE_OPT_NONEG, diff_opt_stat),
+               OPT_CALLBACK_F(0, "stat-graph-width", options, N_("<width>"),
+                              N_("generate diffstat with a given graph width"),
+                              PARSE_OPT_NONEG, diff_opt_stat),
+               OPT_CALLBACK_F(0, "stat-count", options, N_("<count>"),
+                              N_("generate diffstat with limited lines"),
+                              PARSE_OPT_NONEG, diff_opt_stat),
+               OPT_CALLBACK_F(0, "compact-summary", options, NULL,
+                              N_("generate compact summary in diffstat"),
+                              PARSE_OPT_NOARG, diff_opt_compact_summary),
+               OPT_CALLBACK_F(0, "output-indicator-new",
+                              &options->output_indicators[OUTPUT_INDICATOR_NEW],
+                              N_("<char>"),
+                              N_("specify the character to indicate a new line instead of '+'"),
+                              PARSE_OPT_NONEG, diff_opt_char),
+               OPT_CALLBACK_F(0, "output-indicator-old",
+                              &options->output_indicators[OUTPUT_INDICATOR_OLD],
+                              N_("<char>"),
+                              N_("specify the character to indicate an old line instead of '-'"),
+                              PARSE_OPT_NONEG, diff_opt_char),
+               OPT_CALLBACK_F(0, "output-indicator-context",
+                              &options->output_indicators[OUTPUT_INDICATOR_CONTEXT],
+                              N_("<char>"),
+                              N_("specify the character to indicate a context instead of ' '"),
+                              PARSE_OPT_NONEG, diff_opt_char),
+
+               OPT_GROUP(N_("Diff rename options")),
+               OPT_CALLBACK_F('B', "break-rewrites", &options->break_opt, N_("<n>[/<m>]"),
+                              N_("break complete rewrite changes into pairs of delete and create"),
+                              PARSE_OPT_NONEG | PARSE_OPT_OPTARG,
+                              diff_opt_break_rewrites),
+               OPT_CALLBACK_F('M', "find-renames", options, N_("<n>"),
+                              N_("detect renames"),
+                              PARSE_OPT_NONEG | PARSE_OPT_OPTARG,
+                              diff_opt_find_renames),
+               OPT_SET_INT_F('D', "irreversible-delete", &options->irreversible_delete,
+                             N_("omit the preimage for deletes"),
+                             1, PARSE_OPT_NONEG),
+               OPT_CALLBACK_F('C', "find-copies", options, N_("<n>"),
+                              N_("detect copies"),
+                              PARSE_OPT_NONEG | PARSE_OPT_OPTARG,
+                              diff_opt_find_copies),
+               OPT_BOOL(0, "find-copies-harder", &options->flags.find_copies_harder,
+                        N_("use unmodified files as source to find copies")),
+               OPT_SET_INT_F(0, "no-renames", &options->detect_rename,
+                             N_("disable rename detection"),
+                             0, PARSE_OPT_NONEG),
+               OPT_BOOL(0, "rename-empty", &options->flags.rename_empty,
+                        N_("use empty blobs as rename source")),
+
+               OPT_GROUP(N_("Diff algorithm options")),
+               OPT_BIT(0, "minimal", &options->xdl_opts,
+                       N_("produce the smallest possible diff"),
+                       XDF_NEED_MINIMAL),
+               OPT_BIT_F('w', "ignore-all-space", &options->xdl_opts,
+                         N_("ignore whitespace when comparing lines"),
+                         XDF_IGNORE_WHITESPACE, PARSE_OPT_NONEG),
+               OPT_BIT_F('b', "ignore-space-change", &options->xdl_opts,
+                         N_("ignore changes in amount of whitespace"),
+                         XDF_IGNORE_WHITESPACE_CHANGE, PARSE_OPT_NONEG),
+               OPT_BIT_F(0, "ignore-space-at-eol", &options->xdl_opts,
+                         N_("ignore changes in whitespace at EOL"),
+                         XDF_IGNORE_WHITESPACE_AT_EOL, PARSE_OPT_NONEG),
+               OPT_BIT_F(0, "ignore-cr-at-eol", &options->xdl_opts,
+                         N_("ignore carrier-return at the end of line"),
+                         XDF_IGNORE_CR_AT_EOL, PARSE_OPT_NONEG),
+               OPT_BIT_F(0, "ignore-blank-lines", &options->xdl_opts,
+                         N_("ignore changes whose lines are all blank"),
+                         XDF_IGNORE_BLANK_LINES, PARSE_OPT_NONEG),
+
+               OPT_GROUP(N_("Diff other options")),
+               OPT_CALLBACK_F(0, "relative", options, N_("<prefix>"),
+                              N_("when run from subdir, exclude changes outside and show relative paths"),
+                              PARSE_OPT_NONEG | PARSE_OPT_OPTARG,
+                              diff_opt_relative),
+               { OPTION_CALLBACK, 0, "output", options, N_("<file>"),
+                 N_("Output to a specific file"),
+                 PARSE_OPT_NONEG, NULL, 0, diff_opt_output },
+
+               OPT_END()
+       };
+
+       ALLOC_ARRAY(options->parseopts, ARRAY_SIZE(parseopts));
+       memcpy(options->parseopts, parseopts, sizeof(parseopts));
+}
+
 int diff_opt_parse(struct diff_options *options,
                   const char **av, int ac, const char *prefix)
 {
@@ -4929,107 +5218,18 @@ int diff_opt_parse(struct diff_options *options,
        if (!prefix)
                prefix = "";
 
-       /* Output format options */
-       if (!strcmp(arg, "-p") || !strcmp(arg, "-u") || !strcmp(arg, "--patch")
-           || opt_arg(arg, 'U', "unified", &options->context))
-               enable_patch_output(&options->output_format);
-       else if (!strcmp(arg, "--raw"))
-               options->output_format |= DIFF_FORMAT_RAW;
-       else if (!strcmp(arg, "--patch-with-raw")) {
-               enable_patch_output(&options->output_format);
-               options->output_format |= DIFF_FORMAT_RAW;
-       } else if (!strcmp(arg, "--numstat"))
-               options->output_format |= DIFF_FORMAT_NUMSTAT;
-       else if (!strcmp(arg, "--shortstat"))
-               options->output_format |= DIFF_FORMAT_SHORTSTAT;
-       else if (skip_prefix(arg, "-X", &arg) ||
-                skip_to_optional_arg(arg, "--dirstat", &arg))
-               return parse_dirstat_opt(options, arg);
-       else if (!strcmp(arg, "--cumulative"))
-               return parse_dirstat_opt(options, "cumulative");
-       else if (skip_to_optional_arg(arg, "--dirstat-by-file", &arg)) {
-               parse_dirstat_opt(options, "files");
-               return parse_dirstat_opt(options, arg);
-       }
-       else if (!strcmp(arg, "--check"))
-               options->output_format |= DIFF_FORMAT_CHECKDIFF;
-       else if (!strcmp(arg, "--summary"))
-               options->output_format |= DIFF_FORMAT_SUMMARY;
-       else if (!strcmp(arg, "--patch-with-stat")) {
-               enable_patch_output(&options->output_format);
-               options->output_format |= DIFF_FORMAT_DIFFSTAT;
-       } else if (!strcmp(arg, "--name-only"))
-               options->output_format |= DIFF_FORMAT_NAME;
-       else if (!strcmp(arg, "--name-status"))
-               options->output_format |= DIFF_FORMAT_NAME_STATUS;
-       else if (!strcmp(arg, "-s") || !strcmp(arg, "--no-patch"))
-               options->output_format |= DIFF_FORMAT_NO_OUTPUT;
-       else if (starts_with(arg, "--stat"))
-               /* --stat, --stat-width, --stat-name-width, or --stat-count */
-               return stat_opt(options, av);
-       else if (!strcmp(arg, "--compact-summary")) {
-                options->flags.stat_with_summary = 1;
-                options->output_format |= DIFF_FORMAT_DIFFSTAT;
-       } else if (!strcmp(arg, "--no-compact-summary"))
-                options->flags.stat_with_summary = 0;
-       else if (skip_prefix(arg, "--output-indicator-new=", &arg))
-               options->output_indicators[OUTPUT_INDICATOR_NEW] = arg[0];
-       else if (skip_prefix(arg, "--output-indicator-old=", &arg))
-               options->output_indicators[OUTPUT_INDICATOR_OLD] = arg[0];
-       else if (skip_prefix(arg, "--output-indicator-context=", &arg))
-               options->output_indicators[OUTPUT_INDICATOR_CONTEXT] = arg[0];
-
-       /* renames options */
-       else if (starts_with(arg, "-B") ||
-                skip_to_optional_arg(arg, "--break-rewrites", NULL)) {
-               if ((options->break_opt = diff_scoreopt_parse(arg)) == -1)
-                       return error("invalid argument to -B: %s", arg+2);
-       }
-       else if (starts_with(arg, "-M") ||
-                skip_to_optional_arg(arg, "--find-renames", NULL)) {
-               if ((options->rename_score = diff_scoreopt_parse(arg)) == -1)
-                       return error("invalid argument to -M: %s", arg+2);
-               options->detect_rename = DIFF_DETECT_RENAME;
-       }
-       else if (!strcmp(arg, "-D") || !strcmp(arg, "--irreversible-delete")) {
-               options->irreversible_delete = 1;
-       }
-       else if (starts_with(arg, "-C") ||
-                skip_to_optional_arg(arg, "--find-copies", NULL)) {
-               if (options->detect_rename == DIFF_DETECT_COPY)
-                       options->flags.find_copies_harder = 1;
-               if ((options->rename_score = diff_scoreopt_parse(arg)) == -1)
-                       return error("invalid argument to -C: %s", arg+2);
-               options->detect_rename = DIFF_DETECT_COPY;
-       }
-       else if (!strcmp(arg, "--no-renames"))
-               options->detect_rename = 0;
-       else if (!strcmp(arg, "--rename-empty"))
-               options->flags.rename_empty = 1;
-       else if (!strcmp(arg, "--no-rename-empty"))
-               options->flags.rename_empty = 0;
-       else if (skip_to_optional_arg_default(arg, "--relative", &arg, NULL)) {
-               options->flags.relative_name = 1;
-               if (arg)
-                       options->prefix = arg;
-       }
+       ac = parse_options(ac, av, prefix, options->parseopts, NULL,
+                          PARSE_OPT_KEEP_DASHDASH |
+                          PARSE_OPT_KEEP_UNKNOWN |
+                          PARSE_OPT_NO_INTERNAL_HELP |
+                          PARSE_OPT_ONE_SHOT |
+                          PARSE_OPT_STOP_AT_NON_OPTION);
+
+       if (ac)
+               return ac;
 
        /* xdiff options */
-       else if (!strcmp(arg, "--minimal"))
-               DIFF_XDL_SET(options, NEED_MINIMAL);
-       else if (!strcmp(arg, "--no-minimal"))
-               DIFF_XDL_CLR(options, NEED_MINIMAL);
-       else if (!strcmp(arg, "-w") || !strcmp(arg, "--ignore-all-space"))
-               DIFF_XDL_SET(options, IGNORE_WHITESPACE);
-       else if (!strcmp(arg, "-b") || !strcmp(arg, "--ignore-space-change"))
-               DIFF_XDL_SET(options, IGNORE_WHITESPACE_CHANGE);
-       else if (!strcmp(arg, "--ignore-space-at-eol"))
-               DIFF_XDL_SET(options, IGNORE_WHITESPACE_AT_EOL);
-       else if (!strcmp(arg, "--ignore-cr-at-eol"))
-               DIFF_XDL_SET(options, IGNORE_CR_AT_EOL);
-       else if (!strcmp(arg, "--ignore-blank-lines"))
-               DIFF_XDL_SET(options, IGNORE_BLANK_LINES);
-       else if (!strcmp(arg, "--indent-heuristic"))
+       if (!strcmp(arg, "--indent-heuristic"))
                DIFF_XDL_SET(options, INDENT_HEURISTIC);
        else if (!strcmp(arg, "--no-indent-heuristic"))
                DIFF_XDL_CLR(options, INDENT_HEURISTIC);
@@ -5074,8 +5274,6 @@ int diff_opt_parse(struct diff_options *options,
                options->flags.text = 1;
        else if (!strcmp(arg, "-R"))
                options->flags.reverse_diff = 1;
-       else if (!strcmp(arg, "--find-copies-harder"))
-               options->flags.find_copies_harder = 1;
        else if (!strcmp(arg, "--follow"))
                options->flags.follow_renames = 1;
        else if (!strcmp(arg, "--no-follow")) {
@@ -5223,21 +5421,7 @@ int diff_opt_parse(struct diff_options *options,
        else if (opt_arg(arg, '\0', "inter-hunk-context",
                         &options->interhunkcontext))
                ;
-       else if (!strcmp(arg, "-W"))
-               options->flags.funccontext = 1;
-       else if (!strcmp(arg, "--function-context"))
-               options->flags.funccontext = 1;
-       else if (!strcmp(arg, "--no-function-context"))
-               options->flags.funccontext = 0;
-       else if ((argcount = parse_long_opt("output", av, &optarg))) {
-               char *path = prefix_filename(prefix, optarg);
-               options->file = xfopen(path, "w");
-               options->close_file = 1;
-               if (options->use_color != GIT_COLOR_ALWAYS)
-                       options->use_color = GIT_COLOR_NEVER;
-               free(path);
-               return argcount;
-       } else
+       else
                return 0;
        return 1;
 }
@@ -5278,47 +5462,6 @@ int parse_rename_score(const char **cp_p)
        return (int)((num >= scale) ? MAX_SCORE : (MAX_SCORE * num / scale));
 }
 
-static int diff_scoreopt_parse(const char *opt)
-{
-       int opt1, opt2, cmd;
-
-       if (*opt++ != '-')
-               return -1;
-       cmd = *opt++;
-       if (cmd == '-') {
-               /* convert the long-form arguments into short-form versions */
-               if (skip_prefix(opt, "break-rewrites", &opt)) {
-                       if (*opt == 0 || *opt++ == '=')
-                               cmd = 'B';
-               } else if (skip_prefix(opt, "find-copies", &opt)) {
-                       if (*opt == 0 || *opt++ == '=')
-                               cmd = 'C';
-               } else if (skip_prefix(opt, "find-renames", &opt)) {
-                       if (*opt == 0 || *opt++ == '=')
-                               cmd = 'M';
-               }
-       }
-       if (cmd != 'M' && cmd != 'C' && cmd != 'B')
-               return -1; /* that is not a -M, -C, or -B option */
-
-       opt1 = parse_rename_score(&opt);
-       if (cmd != 'B')
-               opt2 = 0;
-       else {
-               if (*opt == 0)
-                       opt2 = 0;
-               else if (*opt != '/')
-                       return -1; /* we expect -B80/99 or -B80 */
-               else {
-                       opt++;
-                       opt2 = parse_rename_score(&opt);
-               }
-       }
-       if (*opt != 0)
-               return -1;
-       return opt1 | (opt2 << 16);
-}
-
 struct diff_queue_struct diff_queued_diff;
 
 void diff_q(struct diff_queue_struct *queue, struct diff_filepair *dp)