vsh: Refactor parsed option and command assignment

Refactor the very old opaque logic (using multiple bitmaps) by
fully-allocating vshCmdOpt for each possible argument and then filling
them as they go rather than allocating them each time after it's parsed.

This simplifies the checkers and removes the need to cross-reference
multiple arrays.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>

tools/vsh.c

@@ -476,81 +476,36 @@ vshCmddefCheckInternals(vshControl *ctl,
     return 0;
 }
 
-/* Parse the options associated with @cmd, i.e. test whether options are
- * required or need an argument and fill the appropriate caller-provided bitmaps
- */
-static void
-vshCmddefOptParse(const vshCmdDef *cmd,
-                  uint64_t *opts_need_arg,
-                  uint64_t *opts_required)
-{
-    size_t i;
 
-    *opts_need_arg = 0;
+static vshCmdOpt *
-    *opts_required = 0;
+vshCmdGetOption(vshControl *ctl,
-
+                vshCmd *cmd,
-    if (!cmd->opts)
-        return;
-
-    for (i = 0; cmd->opts[i].name; i++) {
-        const vshCmdOptDef *opt = &cmd->opts[i];
-
-        if (opt->type == VSH_OT_BOOL)
-            continue;
-
-        if (opt->type == VSH_OT_ALIAS)
-            continue; /* skip the alias option */
-
-        if (opt->positional || opt->unwanted_positional)
-            *opts_need_arg |= 1ULL << i;
-
-        if (opt->required)
-            *opts_required |= 1ULL << i;
-    }
-}
-
-static vshCmdOptDef helpopt = {
-    .name = "help",
-    .type = VSH_OT_BOOL,
-    .help = N_("print help for this function")
-};
-
-static const vshCmdOptDef *
-vshCmddefGetOption(vshControl *ctl,
-                   const vshCmdDef *cmd,
                 const char *name,
-                   uint64_t *opts_seen,
-                   size_t *opt_index,
                 char **optstr,
                 bool report)
 {
-    size_t i;
     g_autofree char *alias = NULL;
+    vshCmdOpt *n;
 
-    if (STREQ(name, helpopt.name))
+    for (n = cmd->opts; n && n->def; n++) {
-        return &helpopt;
+        if (STRNEQ(n->def->name, name))
-
-    for (i = 0; cmd->opts && cmd->opts[i].name; i++) {
-        const vshCmdOptDef *opt = &cmd->opts[i];
-
-        if (STRNEQ(opt->name, name))
             continue;
 
-        if (opt->type == VSH_OT_ALIAS) {
+        if (n->def->type == VSH_OT_ALIAS) {
             char *value;
 
             /* Two types of replacements:
                opt->help = "string": straight replacement of name
                opt->help = "string=value": treat boolean flag as
                alias of option and its default value */
-            alias = g_strdup(opt->help);
+            alias = g_strdup(n->def->help);
             name = alias;
             if ((value = strchr(name, '='))) {
                 *value = '\0';
                 if (*optstr) {
                     if (report)
                         vshError(ctl, _("invalid '=' after option --%1$s"),
-                                 opt->name);
+                                 n->def->name);
                     return NULL;
                 }
                 *optstr = g_strdup(value + 1);
@@ -558,71 +513,121 @@ vshCmddefGetOption(vshControl *ctl,
             continue;
         }
 
-        if ((*opts_seen & (1ULL << i)) && opt->type != VSH_OT_ARGV) {
+        if (n->present && n->def->type != VSH_OT_ARGV) {
             if (report)
                 vshError(ctl, _("option --%1$s already seen"), name);
+
             return NULL;
         }
 
-        *opts_seen |= 1ULL << i;
+        return n;
-        *opt_index = i;
-        return opt;
     }
 
     /* The 'help' command ignores extra options */
-    if (STRNEQ(cmd->name, "help") && report) {
+    if (STRNEQ(cmd->def->name, "help") && report) {
         vshError(ctl, _("command '%1$s' doesn't support option --%2$s"),
-                 cmd->name, name);
+                 cmd->def->name, name);
     }
     return NULL;
 }
 
-static const vshCmdOptDef *
+
-vshCmddefGetData(const vshCmdDef *cmd, uint64_t *opts_need_arg,
+static void
-                 uint64_t *opts_seen)
+vshCmdOptAssign(vshCmd *cmd,
+                vshCmdOpt *opt,
+                const char *val)
 {
-    size_t i;
+    cmd->lastopt = opt;
-    const vshCmdOptDef *opt;
 
-    if (!*opts_need_arg)
+    opt->present = true;
-        return NULL;
 
-    /* Grab least-significant set bit */
+    switch (opt->def->type) {
-    i = __builtin_ffsl(*opts_need_arg) - 1;
+    case VSH_OT_BOOL:
-    opt = &cmd->opts[i];
+        /* nothing to do */
-    if (opt->type != VSH_OT_ARGV)
+        break;
-        *opts_need_arg &= ~(1ULL << i);
+
-    *opts_seen |= 1ULL << i;
+    case VSH_OT_STRING:
-    return opt;
+    case VSH_OT_INT:
+        opt->data = g_strdup(val);
+        break;
+
+    case VSH_OT_ARGV:
+        VIR_EXPAND_N(opt->argv, opt->nargv, 2);
+        /* VIR_EXPAND_N updates count */
+        opt->nargv--;
+        opt->argv[opt->nargv - 1] = g_strdup(val);
+        /* for completers to work properly we need to also remember the last
+         * field in 'data' */
+        g_clear_pointer(&opt->data, g_free);
+        opt->data = g_strdup(val);
+        break;
+
+    case VSH_OT_NONE:
+    case VSH_OT_ALIAS:
+        /* impossible code path */
+        break;
     }
+}
+
+
+/**
+ * vshCmdGetNextPositionalOpt:
+ * @cmd: command structure
+ *
+ * Get next unpopulated positional argument definition.
+ */
+static vshCmdOpt *
+vshCmdGetNextPositionalOpt(const vshCmd *cmd)
+{
+    vshCmdOpt *n;
+
+    for (n = cmd->opts; n && n->def; n++) {
+        /* Consider only "positional" options. Tests ensure that boolean options
+         * don't set these. */
+        if (!(n->def->positional || n->def->unwanted_positional))
+            continue;
+
+        /* 'VSH_OT_ARGV' positionals must allow multiple arguments */
+        if (n->present &&
+            n->def->type != VSH_OT_ARGV)
+            continue;
+
+        return n;
+    }
+
+    return NULL;
+}
+
 
 /*
  * Checks for required options
  */
 static int
-vshCommandCheckOpts(vshControl *ctl, const vshCmd *cmd, uint64_t opts_required,
+vshCommandCheckOpts(vshControl *ctl,
-                    uint64_t opts_seen)
+                    const vshCmd *cmd)
 {
-    const vshCmdDef *def = cmd->def;
+    vshCmdOpt *n;
-    size_t i;
-
-    opts_required &= ~opts_seen;
-    if (!opts_required)
-        return 0;
-
-    for (i = 0; def->opts[i].name; i++) {
-        if (opts_required & (1ULL << i)) {
-            const vshCmdOptDef *opt = &def->opts[i];
 
+    for (n = cmd->opts; n && n->def; n++) {
+        if (!n->present && n->def->required) {
+            if (n->def->positional) {
+                vshError(ctl,
+                         _("command '%1$s' requires <%2$s> option"),
+                         cmd->def->name, n->def->name);
+            } else {
                 vshError(ctl,
-                     opt->positional ?
-                     _("command '%1$s' requires <%2$s> option") :
                          _("command '%1$s' requires --%2$s option"),
-                     def->name, opt->name);
+                         cmd->def->name, n->def->name);
-        }
             }
+
             return -1;
         }
+    }
+
+
+    return 0;
+}
+
 
 static const vshCmdGrp *
 vshCmdGrpSearch(const char *grpname)
@@ -776,24 +781,6 @@ vshCmddefHelp(const vshCmdDef *def)
  * Utils for work with runtime commands data
  * ---------------
  */
-static void
-vshCommandOptFree(vshCmdOpt * arg)
-{
-    vshCmdOpt *a = arg;
-
-    while (a) {
-        vshCmdOpt *tmp = a;
-
-        a = a->next;
-
-        g_free(tmp->data);
-        /* 'argv' doesn't own the strings themselves */
-        g_free(tmp->argv);
-        g_free(tmp->argvstr);
-        g_free(tmp);
-    }
-}
-
 static void
 vshCommandFree(vshCmd *cmd)
 {
@@ -801,10 +788,18 @@ vshCommandFree(vshCmd *cmd)
 
     while (c) {
         vshCmd *tmp = c;
+        vshCmdOpt *n;
 
         c = c->next;
 
-        vshCommandOptFree(tmp->opts);
+        for (n = tmp->opts; n && n->def; n++) {
+            g_free(n->data);
+            g_strfreev(n->argv);
+            g_free(n->argvstr);
+        }
+
+        g_free(tmp->opts);
+
         g_free(tmp);
     }
 }
@@ -826,39 +821,36 @@ G_DEFINE_AUTOPTR_CLEANUP_FUNC(vshCmd, vshCommandFree);
  * is set. No error messages are issued if a value is returned.
  */
 static int
-vshCommandOpt(const vshCmd *cmd, const char *name, vshCmdOpt **opt,
+vshCommandOpt(const vshCmd *cmd,
+              const char *name,
+              vshCmdOpt **opt,
               bool needData)
 {
-    vshCmdOpt *candidate = cmd->opts;
+    vshCmdOpt *n;
-    const vshCmdOptDef *valid = cmd->def->opts;
-    int ret = 0;
 
-    /* See if option is valid and/or required.  */
     *opt = NULL;
 
-    while (valid && valid->name) {
+    for (n = cmd->opts; n && n->def; n++) {
-        if (STREQ(name, valid->name))
+        if (STRNEQ(name, n->def->name))
-            break;
+            continue;
-        valid++;
+
+        if (!cmd->skipChecks)
+            assert(!needData || n->def->type != VSH_OT_BOOL);
+
+        if (n->present) {
+            *opt = n;
+            return 1;
+        } else {
+            return 0;
+        }
     }
 
     if (!cmd->skipChecks)
-        assert(valid && (!needData || valid->type != VSH_OT_BOOL));
+        assert(false);
 
-    if (valid && valid->required)
+    return -1;
-        ret = -1;
+}
 
-    /* See if option is present on command line.  */
-    while (candidate) {
-        if (STREQ(candidate->def->name, name)) {
-            *opt = candidate;
-            ret = 1;
-            break;
-        }
-        candidate = candidate->next;
-    }
-    return ret;
-}
 
 /**
  * vshCommandOptInt:
@@ -1238,39 +1230,6 @@ vshCommandOptBool(const vshCmd *cmd, const char *name)
 }
 
 
-static vshCmdOpt *
-vshCommandOptArgvInternal(const vshCmd *cmd,
-                          const char *name)
-{
-    vshCmdOpt *first = NULL;
-    vshCmdOpt *opt;
-    size_t nargv = 0;
-    size_t nargv_alloc = 0;
-
-    for (opt = cmd->opts; opt; opt = opt->next) {
-        if (STRNEQ(opt->def->name, name))
-            continue;
-
-        if (!first) {
-            /* Return existing data if we'we already processed it */
-            if (opt->argv)
-                return opt;
-
-            first = opt;
-        }
-
-        /* extra NULL terminator */
-        VIR_RESIZE_N(first->argv, nargv_alloc, nargv, 2);
-        first->argv[nargv++] = opt->data;
-    }
-
-    if (first)
-        first->argvstr = g_strjoinv(" ", (GStrv) first->argv);
-
-    return first;
-}
-
-
 /**
  * vshCommandOptArgv:
  * @cmd: command reference
@@ -1284,12 +1243,12 @@ const char **
 vshCommandOptArgv(const vshCmd *cmd,
                   const char *name)
 {
-    vshCmdOpt *opt = vshCommandOptArgvInternal(cmd, name);
+    vshCmdOpt *opt;
 
-    if (!opt)
+    if (vshCommandOpt(cmd, name, &opt, true) != 1)
         return NULL;
 
-    return opt->argv;
+    return (const char **) opt->argv;
 }
 
 
@@ -1305,11 +1264,14 @@ const char *
 vshCommandOptArgvString(const vshCmd *cmd,
                         const char *name)
 {
-    vshCmdOpt *opt = vshCommandOptArgvInternal(cmd, name);
+    vshCmdOpt *opt;
 
-    if (!opt)
+    if (vshCommandOpt(cmd, name, &opt, true) != 1)
         return NULL;
 
+    if (!opt->argvstr)
+        opt->argvstr = g_strjoinv(" ", opt->argv);
+
     return opt->argvstr;
 }
 
@@ -1444,14 +1406,71 @@ struct _vshCommandParser {
     char **arg_end;
 };
 
+
+static vshCmd *
+vshCmdNewHelp(const char *name)
+{
+    vshCmd *c = g_new0(vshCmd, 1);
+
+    c->def = vshCmddefSearch("help");
+
+    c->opts = g_new0(vshCmdOpt, 2);
+    c->opts->def = c->def->opts;
+    c->opts->data = g_strdup(name);
+    c->opts->present = true;
+
+    return c;
+}
+
+
+static vshCmd *
+vshCmdNew(vshControl *ctl,
+          const char *cmdname,
+          bool report)
+{
+    g_autoptr(vshCmd) c = g_new0(vshCmd, 1);
+    const vshCmdOptDef *optdef;
+    vshCmdOpt *opt;
+    size_t nopts = 0;
+
+    if (!(c->def = vshCmddefSearch(cmdname))) {
+        if (report)
+            vshError(ctl, _("unknown command: '%1$s'"), cmdname);
+
+        return NULL;
+    }
+
+    /* resolve command alias */
+    if (c->def->alias) {
+        if (!(c->def = vshCmddefSearch(c->def->alias))) {
+            /* dead code: self-test ensures that the alias exists thus no error reported here */
+            return NULL;
+        }
+    }
+
+    /* Find number of arguments */
+    for (optdef = c->def->opts; optdef && optdef->name; optdef++)
+        nopts++;
+
+    c->opts = g_new0(vshCmdOpt, nopts + 1);
+    opt = c->opts;
+
+    /* populate links to definitions */
+    for (optdef = c->def->opts; optdef && optdef->name; optdef++) {
+        opt->def = optdef;
+        opt++;
+    }
+
+    return g_steal_pointer(&c);
+}
+
+
 static bool
 vshCommandParse(vshControl *ctl, vshCommandParser *parser, vshCmd **partial)
 {
+    g_autoptr(vshCmd) cmd = NULL;
     char *tkdata = NULL;
     vshCmd *clast = NULL;
-    vshCmdOpt *first = NULL;
-    vshCmdOpt *last = NULL;
-    const vshCmdDef *cmd = NULL;
 
     if (!partial) {
         g_clear_pointer(&ctl->cmd, vshCommandFree);
@@ -1460,20 +1479,13 @@ vshCommandParse(vshControl *ctl, vshCommandParser *parser, vshCmd **partial)
     while (1) {
         vshCommandToken tk;
         bool data_only = false;
-        uint64_t opts_need_arg = 0;
-        uint64_t opts_required = 0;
-        uint64_t opts_seen = 0;
-
-        cmd = NULL;
-        first = NULL;
-        last = NULL;
 
         if (partial) {
             g_clear_pointer(partial, vshCommandFree);
         }
 
         while (1) {
-            const vshCmdOptDef *opt = NULL;
+            vshCmdOpt *opt = NULL;
 
             tkdata = NULL;
             tk = parser->getNextArg(ctl, parser, &tkdata, true);
@@ -1494,48 +1506,34 @@ vshCommandParse(vshControl *ctl, vshCommandParser *parser, vshCmd **partial)
                     } while (tk == VSH_TK_ARG);
                     VIR_FREE(tkdata);
                     break;
-                } else if (!(cmd = vshCmddefSearch(tkdata))) {
-                    if (!partial)
-                        vshError(ctl, _("unknown command: '%1$s'"), tkdata);
-                    goto syntaxError;   /* ... or ignore this command only? */
                 }
 
-                /* aliases need to be resolved to the actual commands */
+                if (!(cmd = vshCmdNew(ctl, tkdata, !partial)))
-                if (cmd->alias) {
-                    VIR_FREE(tkdata);
-                    tkdata = g_strdup(cmd->alias);
-                    if (!(cmd = vshCmddefSearch(tkdata))) {
-                        /* self-test ensures that the alias exists */
-                        vshError(ctl, _("unknown command: '%1$s'"), tkdata);
                     goto syntaxError;
-                    }
-                }
 
-                vshCmddefOptParse(cmd, &opts_need_arg, &opts_required);
                 VIR_FREE(tkdata);
             } else if (data_only) {
                 goto get_data;
             } else if (tkdata[0] == '-' && tkdata[1] == '-' &&
                        g_ascii_isalnum(tkdata[2])) {
                 char *optstr = strchr(tkdata + 2, '=');
-                size_t opt_index = 0;
 
                 if (optstr) {
                     *optstr = '\0'; /* convert the '=' to '\0' */
                     optstr = g_strdup(optstr + 1);
                 }
+
                 /* Special case 'help' to ignore all spurious options */
-                if (!(opt = vshCmddefGetOption(ctl, cmd, tkdata + 2,
+                if (!(opt = vshCmdGetOption(ctl, cmd, tkdata + 2,
-                                               &opts_seen, &opt_index,
                                             &optstr, partial == NULL))) {
                     VIR_FREE(optstr);
-                    if (STREQ(cmd->name, "help"))
+                    if (STREQ(cmd->def->name, "help"))
                         continue;
                     goto syntaxError;
                 }
                 VIR_FREE(tkdata);
 
-                if (opt->type != VSH_OT_BOOL) {
+                if (opt->def->type != VSH_OT_BOOL) {
                     /* option data */
                     if (optstr)
                         tkdata = optstr;
@@ -1545,33 +1543,23 @@ vshCommandParse(vshControl *ctl, vshCommandParser *parser, vshCmd **partial)
                         goto syntaxError;
                     if (tk != VSH_TK_ARG) {
                         if (partial) {
-                            vshCmdOpt *arg = g_new0(vshCmdOpt, 1);
+                            vshCmdOptAssign(cmd, opt, tkdata);
-                            arg->def = opt;
+                            VIR_FREE(tkdata);
-                            arg->data = g_steal_pointer(&tkdata);
-                            arg->next = NULL;
-
-                            if (!first)
-                                first = arg;
-                            if (last)
-                                last->next = arg;
-                            last = arg;
                         } else {
                             vshError(ctl,
                                      _("expected syntax: --%1$s <%2$s>"),
-                                     opt->name,
+                                     opt->def->name,
-                                     opt->type ==
+                                     opt->def->type ==
                                      VSH_OT_INT ? _("number") : _("string"));
                         }
                         goto syntaxError;
                     }
-                    if (opt->type != VSH_OT_ARGV)
-                        opts_need_arg &= ~(1ULL << opt_index);
                 } else {
                     tkdata = NULL;
                     if (optstr) {
                         if (!partial)
                             vshError(ctl, _("invalid '=' after option --%1$s"),
-                                     opt->name);
+                                     opt->def->name);
                         VIR_FREE(optstr);
                         goto syntaxError;
                     }
@@ -1584,85 +1572,52 @@ vshCommandParse(vshControl *ctl, vshCommandParser *parser, vshCmd **partial)
             } else {
  get_data:
                 /* Special case 'help' to ignore spurious data */
-                if (!(opt = vshCmddefGetData(cmd, &opts_need_arg,
+                if (!(opt = vshCmdGetNextPositionalOpt(cmd)) &&
-                                             &opts_seen)) &&
+                    STRNEQ(cmd->def->name, "help")) {
-                     STRNEQ(cmd->name, "help")) {
                     if (!partial)
                         vshError(ctl, _("unexpected data '%1$s'"), tkdata);
                     goto syntaxError;
                 }
             }
+
             if (opt) {
-                /* save option */
+                vshCmdOptAssign(cmd, opt, tkdata);
-                vshCmdOpt *arg = g_new0(vshCmdOpt, 1);
+                VIR_FREE(tkdata);
-
-                arg->def = opt;
-                arg->data = g_steal_pointer(&tkdata);
-                arg->next = NULL;
-
-                if (!first)
-                    first = arg;
-                if (last)
-                    last->next = arg;
-                last = arg;
 
                 if (!partial)
                     vshDebug(ctl, VSH_ERR_INFO, "%s: %s(%s): %s\n",
-                             cmd->name,
+                             cmd->def->name,
-                             opt->name,
+                             opt->def->name,
-                             opt->type != VSH_OT_BOOL ? _("optdata") : _("bool"),
+                             opt->def->type != VSH_OT_BOOL ? _("optdata") : _("bool"),
-                             opt->type != VSH_OT_BOOL ? arg->data : _("(none)"));
+                             opt->def->type != VSH_OT_BOOL ? opt->data : _("(none)"));
             }
         }
 
         /* command parsed -- allocate new struct for the command */
         if (cmd) {
-            vshCmd *c = g_new0(vshCmd, 1);
+            /* if we encountered --help, replace parsed command with 'help <cmdname>' */
-            vshCmdOpt *tmpopt = first;
+            if (cmd->helpOptionSeen) {
+                vshCmd *helpcmd = vshCmdNewHelp(cmd->def->name);
 
-            /* if we encountered --help, replace parsed command with
+                vshCommandFree(cmd);
-             * 'help <cmdname>' */
+                cmd = helpcmd;
-            for (tmpopt = first; tmpopt; tmpopt = tmpopt->next) {
-                const vshCmdDef *help;
-                if (STRNEQ(tmpopt->def->name, "help"))
-                    continue;
-
-                /* the self-test code ensures that help exists */
-                if (!(help = vshCmddefSearch("help")))
-                    break;
-
-                vshCommandOptFree(first);
-                first = g_new0(vshCmdOpt, 1);
-                first->def = help->opts;
-                first->data = g_strdup(cmd->name);
-                first->next = NULL;
-
-                cmd = help;
-                opts_required = 0;
-                opts_seen = 0;
-                break;
             }
 
-            c->opts = g_steal_pointer(&first);
-            c->lastopt = last;
-            c->def = cmd;
-            c->next = NULL;
-
             if (!partial &&
-                vshCommandCheckOpts(ctl, c, opts_required, opts_seen) < 0) {
+                vshCommandCheckOpts(ctl, cmd) < 0) {
-                vshCommandFree(c);
+                vshCommandFree(cmd);
                 goto syntaxError;
             }
 
             if (partial) {
                 vshCommandFree(*partial);
-                *partial = c;
+                *partial = g_steal_pointer(&cmd);
             } else {
                 if (!ctl->cmd)
-                    ctl->cmd = c;
+                    ctl->cmd = cmd;
                 if (clast)
-                    clast->next = c;
+                    clast->next = cmd;
-                clast = c;
+                clast = g_steal_pointer(&cmd);
             }
         }
 
@@ -1674,17 +1629,9 @@ vshCommandParse(vshControl *ctl, vshCommandParser *parser, vshCmd **partial)
 
  syntaxError:
     if (partial) {
-        vshCmd *tmp;
+        *partial = g_steal_pointer(&cmd);
-
-        tmp = g_new0(vshCmd, 1);
-        tmp->opts = first;
-        tmp->lastopt = last;
-        tmp->def = cmd;
-
-        *partial = tmp;
     } else {
         g_clear_pointer(&ctl->cmd, vshCommandFree);
-        vshCommandOptFree(first);
     }
     VIR_FREE(tkdata);
     return false;
@@ -2739,43 +2686,24 @@ vshReadlineCommandGenerator(void)
 
 
 static char **
-vshReadlineOptionsGenerator(const vshCmdDef *cmd,
+vshReadlineOptionsGenerator(vshCmd *cmd)
-                            vshCmd *last)
 {
-    size_t list_index = 0;
     size_t ret_size = 0;
     g_auto(GStrv) ret = NULL;
+    vshCmdOpt *n;
 
-    if (!cmd)
+    for (n = cmd->opts; n && n->def; n++) {
-        return NULL;
-
-    if (!cmd->opts)
-        return NULL;
-
-    for (list_index = 0; cmd->opts[list_index].name; list_index++) {
-        const char *name = cmd->opts[list_index].name;
-        bool exists = false;
-        vshCmdOpt *opt =  last->opts;
-
         /* Skip aliases, we do not report them in help output either. */
-        if (cmd->opts[list_index].type == VSH_OT_ALIAS)
+        if (n->def->type == VSH_OT_ALIAS)
             continue;
 
-        while (opt) {
+        /* skip already populated single-instance arguments */
-            if (STREQ(opt->def->name, name) && opt->def->type != VSH_OT_ARGV) {
+        if (n->present && n->def->type != VSH_OT_ARGV)
-                exists = true;
-                break;
-            }
-
-            opt = opt->next;
-        }
-
-        if (exists)
             continue;
 
         VIR_REALLOC_N(ret, ret_size + 2);
 
-        ret[ret_size] = g_strdup_printf("--%s", name);
+        ret[ret_size] = g_strdup_printf("--%s", n->def->name);
         ret_size++;
         /* Terminate the string list properly. */
         ret[ret_size] = NULL;
@@ -2884,7 +2812,7 @@ vshReadlineParse(const char *text, int state)
                                                         partial,
                                                         partial->lastopt->def->completer_flags);
             } else {
-                list = vshReadlineOptionsGenerator(cmd, partial);
+                list = vshReadlineOptionsGenerator(partial);
             }
         }
 

tools/vsh.h

@@ -146,10 +146,11 @@ struct _vshCmdOptDef {
  */
 struct _vshCmdOpt {
     const vshCmdOptDef *def;    /* non-NULL pointer to option definition */
+    bool present;               /* true if option was present on command line */
     char *data;                 /* allocated data, or NULL for bool option */
-    const char **argv;          /* for VSH_OT_ARGV, the list of options */
+    char **argv;                /* for VSH_OT_ARGV, the list of options */
+    size_t nargv;
     char *argvstr;              /* space-joined @argv */
-    vshCmdOpt *next;
 };
 
 /*
@@ -181,6 +182,7 @@ struct _vshCmd {
     vshCmdOpt *lastopt;         /* last option of the commandline */
     vshCmd *next;               /* next command */
     bool skipChecks;            /* skip validity checks when retrieving opts */
+    bool helpOptionSeen;        /* The '--help' option was seen when persing the command */
 };
 
 /*