parse-options: allow -h as a short option

Let callers provide their own handler for the short option -h even
without the flag PARSE_OPT_NO_INTERNAL_HELP, but call the internal
handler (showing usage information) if that is the only parameter.
Implement the first part by checking for -h only if parse_short_opt()
can't find it and returns -2.

Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Jeff King <peff@peff.net>

diff --git a/parse-options.c b/parse-options.c
index 4863966fa597bd8d3e86fa76296ab0541efa7115..47a91920601d74842a0947ce1431c00b3d723972 100644 (file)
--- a/parse-options.c
+++ b/parse-options.c
@@ -410,7 +410,7 @@ void parse_options_start(struct parse_opt_ctx_t *ctx,
                         const struct option *options, int flags)
 {
        memset(ctx, 0, sizeof(*ctx));
-       ctx->argc = argc - 1;
+       ctx->argc = ctx->total = argc - 1;
        ctx->argv = argv + 1;
        ctx->out  = argv;
        ctx->prefix = prefix;
@@ -448,27 +448,32 @@ int parse_options_step(struct parse_opt_ctx_t *ctx,
                        continue;
                }
 
+               /* lone -h asks for help */
+               if (internal_help && ctx->total == 1 && !strcmp(arg + 1, "h"))
+                       goto show_usage;
+
                if (arg[1] != '-') {
                        ctx->opt = arg + 1;
-                       if (internal_help && *ctx->opt == 'h')
-                               goto show_usage;
                        switch (parse_short_opt(ctx, options)) {
                        case -1:
                                goto show_usage_error;
                        case -2:
                                if (ctx->opt)
                                        check_typos(arg + 1, options);
+                               if (internal_help && *ctx->opt == 'h')
+                                       goto show_usage;
                                goto unknown;
                        }
                        if (ctx->opt)
                                check_typos(arg + 1, options);
                        while (ctx->opt) {
-                               if (internal_help && *ctx->opt == 'h')
-                                       goto show_usage;
                                switch (parse_short_opt(ctx, options)) {
                                case -1:
                                        goto show_usage_error;
                                case -2:
+                                       if (internal_help && *ctx->opt == 'h')
+                                               goto show_usage;
+
                                        /* fake a short option thing to hide the fact that we may have
                                         * started to parse aggregated stuff
                                         *

diff --git a/parse-options.h b/parse-options.h
index e8b55ea87aaea6a0e16239fd9b2025c4927d2145..ea4af92a5110554c450665e08fce3a97310e5640 100644 (file)
--- a/parse-options.h
+++ b/parse-options.h
@@ -199,7 +199,7 @@ enum {
 struct parse_opt_ctx_t {
        const char **argv;
        const char **out;
-       int argc, cpidx;
+       int argc, cpidx, total;
        const char *opt;
        int flags;
        const char *prefix;