diff: parse separate options like -S foo

diff --git a/diff.c b/diff.c
index 17873f3d9e88fccbf98e790d243397dcc4ccb24b..bc8fa8e5c7f8496c50f5dea81ca5df191835bd37 100644 (file)
--- a/diff.c
+++ b/diff.c
@@ -2990,9 +2990,50 @@ static int opt_arg(const char *arg, int arg_short, const char *arg_long, int *va
 
 static int diff_scoreopt_parse(const char *opt);
 
+static inline int short_opt(char opt, const char **argv,
+                           const char **optarg)
+{
+       const char *arg = argv[0];
+       if (arg[0] != '-' || arg[1] != opt)
+               return 0;
+       if (arg[2] != '\0') {
+               *optarg = arg + 2;
+               return 1;
+       }
+       if (!argv[1])
+               die("Option '%c' requires a value", opt);
+       *optarg = argv[1];
+       return 2;
+}
+
+int parse_long_opt(const char *opt, const char **argv,
+                  const char **optarg)
+{
+       const char *arg = argv[0];
+       if (arg[0] != '-' || arg[1] != '-')
+               return 0;
+       arg += strlen("--");
+       if (prefixcmp(arg, opt))
+               return 0;
+       arg += strlen(opt);
+       if (*arg == '=') { /* sticked form: --option=value */
+               *optarg = arg + 1;
+               return 1;
+       }
+       if (*arg != '\0')
+               return 0;
+       /* separate form: --option value */
+       if (!argv[1])
+               die("Option '--%s' requires a value", opt);
+       *optarg = argv[1];
+       return 2;
+}
+
 int diff_opt_parse(struct diff_options *options, const char **av, int ac)
 {
        const char *arg = av[0];
+       const char *optarg;
+       int argcount;
 
        /* Output format options */
        if (!strcmp(arg, "-p") || !strcmp(arg, "-u") || !strcmp(arg, "--patch"))
@@ -3149,10 +3190,11 @@ int diff_opt_parse(struct diff_options *options, const char **av, int ac)
                else
                        die("bad --word-diff argument: %s", type);
        }
-       else if (!prefixcmp(arg, "--word-diff-regex=")) {
+       else if ((argcount = parse_long_opt("word-diff-regex", av, &optarg))) {
                if (options->word_diff == DIFF_WORDS_NONE)
                        options->word_diff = DIFF_WORDS_PLAIN;
-               options->word_regex = arg + 18;
+               options->word_regex = optarg;
+               return argcount;
        }
        else if (!strcmp(arg, "--exit-code"))
                DIFF_OPT_SET(options, EXIT_WITH_STATUS);
@@ -3180,18 +3222,26 @@ int diff_opt_parse(struct diff_options *options, const char **av, int ac)
        /* misc options */
        else if (!strcmp(arg, "-z"))
                options->line_termination = 0;
-       else if (!prefixcmp(arg, "-l"))
-               options->rename_limit = strtoul(arg+2, NULL, 10);
-       else if (!prefixcmp(arg, "-S"))
-               options->pickaxe = arg + 2;
+       else if ((argcount = short_opt('l', av, &optarg))) {
+               options->rename_limit = strtoul(optarg, NULL, 10);
+               return argcount;
+       }
+       else if ((argcount = short_opt('S', av, &optarg))) {
+               options->pickaxe = optarg;
+               return argcount;
+       }
        else if (!strcmp(arg, "--pickaxe-all"))
                options->pickaxe_opts = DIFF_PICKAXE_ALL;
        else if (!strcmp(arg, "--pickaxe-regex"))
                options->pickaxe_opts = DIFF_PICKAXE_REGEX;
-       else if (!prefixcmp(arg, "-O"))
-               options->orderfile = arg + 2;
-       else if (!prefixcmp(arg, "--diff-filter="))
-               options->filter = arg + 14;
+       else if ((argcount = short_opt('O', av, &optarg))) {
+               options->orderfile = optarg;
+               return argcount;
+       }
+       else if ((argcount = parse_long_opt("diff-filter", av, &optarg))) {
+               options->filter = optarg;
+               return argcount;
+       }
        else if (!strcmp(arg, "--abbrev"))
                options->abbrev = DEFAULT_ABBREV;
        else if (!prefixcmp(arg, "--abbrev=")) {
@@ -3201,20 +3251,25 @@ int diff_opt_parse(struct diff_options *options, const char **av, int ac)
                else if (40 < options->abbrev)
                        options->abbrev = 40;
        }
-       else if (!prefixcmp(arg, "--src-prefix="))
-               options->a_prefix = arg + 13;
-       else if (!prefixcmp(arg, "--dst-prefix="))
-               options->b_prefix = arg + 13;
+       else if ((argcount = parse_long_opt("src-prefix", av, &optarg))) {
+               options->a_prefix = optarg;
+               return argcount;
+       }
+       else if ((argcount = parse_long_opt("dst-prefix", av, &optarg))) {
+               options->b_prefix = optarg;
+               return argcount;
+       }
        else if (!strcmp(arg, "--no-prefix"))
                options->a_prefix = options->b_prefix = "";
        else if (opt_arg(arg, '\0', "inter-hunk-context",
                         &options->interhunkcontext))
                ;
-       else if (!prefixcmp(arg, "--output=")) {
-               options->file = fopen(arg + strlen("--output="), "w");
+       else if ((argcount = parse_long_opt("output", av, &optarg))) {
+               options->file = fopen(optarg, "w");
                if (!options->file)
                        die_errno("Could not open '%s'", arg + strlen("--output="));
                options->close_file = 1;
+               return argcount;
        } else
                return 0;
        return 1;