isl_arg_parse: support ISL_ARG_SINGLE_DASH flag

Signed-off-by: Sven Verdoolaege <skimo@kotnet.org>

diff --git a/include/isl/arg.h b/include/isl/arg.h
index d64b3db..7d85c01 100644 (file)
--- a/include/isl/arg.h
+++ b/include/isl/arg.h
@@ -50,6 +50,7 @@ struct isl_arg {
        const char              *argument_name;
        size_t                   offset;
        const char              *help_msg;
+#define ISL_ARG_SINGLE_DASH    (1 << 0)
        unsigned                 flags;
        union {
        struct {

diff --git a/isl_arg.c b/isl_arg.c
index eef54a6..a69f4bb 100644 (file)
--- a/isl_arg.c
+++ b/isl_arg.c
@@ -153,11 +153,16 @@ static int print_arg_help(struct isl_arg *decl, const char *prefix, int no)
                return 4;
        }
 
-       if (decl->short_name)
+       if (decl->short_name) {
                printf("  -%c, --", decl->short_name);
-       else
+               len += 8;
+       } else if (decl->flags & ISL_ARG_SINGLE_DASH) {
+               printf("  -");
+               len += 3;
+       } else {
                printf("      --");
-       len += 8;
+               len += 8;
+       }
 
        if (prefix) {
                printf("%s-", prefix);
@@ -528,6 +533,15 @@ static int match_long_name(struct isl_arg *decl,
        return 0;
 }
 
+static const char *skip_dash_dash(struct isl_arg *decl, const char *arg)
+{
+       if (!strncmp(arg, "--", 2))
+               return arg + 2;
+       if ((decl->flags & ISL_ARG_SINGLE_DASH) && arg[0] == '-')
+               return arg + 1;
+       return NULL;
+}
+
 static const char *skip_name(struct isl_arg *decl, const char *arg,
        const char *prefix, int need_argument, int *has_argument)
 {
@@ -545,10 +559,10 @@ static const char *skip_name(struct isl_arg *decl, const char *arg,
        if (!decl->long_name)
                return NULL;
 
-       if (strncmp(arg, "--", 2))
+       name = skip_dash_dash(decl, arg);
+       if (!name)
                return NULL;
 
-       name = arg + 2;
        equal = strchr(name, '=');
        if (need_argument && !equal)
                return NULL;
@@ -680,9 +694,9 @@ static int parse_bool_option(struct isl_arg *decl, const char *arg,
        if (!decl->long_name)
                return 0;
 
-       if (strncmp(arg, "--", 2))
+       arg = skip_dash_dash(decl, arg);
+       if (!arg)
                return 0;
-       arg += 2;
 
        if (prefix) {
                size_t prefix_len = strlen(prefix);