Generalize the option parsing

diff --git a/tig.c b/tig.c
index 859681c..44b6a04 100644 (file)
--- a/tig.c
+++ b/tig.c
@@ -317,6 +317,49 @@ static char opt_encoding[20]       = "";
 static bool opt_utf8           = TRUE;
 static FILE *opt_pipe          = NULL;
 
+enum option_type {
+       OPT_NONE,
+       OPT_INT,
+};
+
+static bool
+check_option(char *opt, char short_name, char *name, enum option_type type, ...)
+{
+       va_list args;
+       char *value = "";
+       int *number;
+
+       if (opt[0] != '-')
+               return FALSE;
+
+       if (opt[1] == '-') {
+               int namelen = strlen(name);
+
+               opt += 2;
+
+               if (strncmp(opt, name, namelen))
+                       return FALSE;
+
+               if (opt[namelen] == '=')
+                       value = opt + namelen + 1;
+
+       } else {
+               if (!short_name || opt[1] != short_name)
+                       return FALSE;
+               value = opt + 2;
+       }
+
+       va_start(args, type);
+       if (type == OPT_INT) {
+               number = va_arg(args, int *);
+               if (isdigit(*value))
+                       *number = atoi(value);
+       }
+       va_end(args);
+
+       return TRUE;
+}
+
 /* Returns the index of log or diff command or -1 to exit. */
 static bool
 parse_options(int argc, char *argv[])
@@ -336,48 +379,22 @@ parse_options(int argc, char *argv[])
                        continue;
                }
 
-               if (!strncmp(opt, "-n", 2) ||
-                   !strncmp(opt, "--line-number", 13)) {
-                       char *num = opt;
-
-                       if (opt[1] == 'n') {
-                               num = opt + 2;
-
-                       } else if (opt[STRING_SIZE("--line-number")] == '=') {
-                               num = opt + STRING_SIZE("--line-number=");
-                       }
-
-                       if (isdigit(*num))
-                               opt_num_interval = atoi(num);
-
+               if (check_option(opt, 'n', "line-number", OPT_INT, &opt_num_interval)) {
                        opt_line_number = TRUE;
                        continue;
                }
 
-               if (!strncmp(opt, "-b", 2) ||
-                   !strncmp(opt, "--tab-size", 10)) {
-                       char *num = opt;
-
-                       if (opt[1] == 'b') {
-                               num = opt + 2;
-
-                       } else if (opt[STRING_SIZE("--tab-size")] == '=') {
-                               num = opt + STRING_SIZE("--tab-size=");
-                       }
-
-                       if (isdigit(*num))
-                               opt_tab_size = MIN(atoi(num), TABSIZE);
+               if (check_option(opt, 'b', "tab-size", OPT_INT, &opt_tab_size)) {
+                       opt_tab_size = MIN(opt_tab_size, TABSIZE);
                        continue;
                }
 
-               if (!strcmp(opt, "-v") ||
-                   !strcmp(opt, "--version")) {
+               if (check_option(opt, 'v', "version", OPT_NONE)) {
                        printf("tig version %s\n", VERSION);
                        return FALSE;
                }
 
-               if (!strcmp(opt, "-h") ||
-                   !strcmp(opt, "--help")) {
+               if (check_option(opt, 'h', "help", OPT_NONE)) {
                        printf(usage);
                        return FALSE;
                }