command: refactor code for simplier lookup

We can more efficiently use command_name struct to
lookup for  lvm_command_enum and avoid many repeated
command name searches since we already know
the enum index that is now stored in 'struct command'.

diff --git a/tools/command.c b/tools/command.c
index 477604c7575458dbcdec5af8533a386a3f4d0749..712a5d161b49f69cc54ab416c8e6d5b719e65705 100644 (file)
--- a/tools/command.c
+++ b/tools/command.c
@@ -377,7 +377,7 @@ static uint64_t _lv_to_bits(struct command *cmd, char *name)
        return lvt_bits;
 }
 
-const struct command_name *find_command_name(const char *name)
+static unsigned _find_lvm_command_enum(const char *name)
 {
        static int _command_names_count = -1;
        int first = 0, last, middle;
@@ -408,28 +408,17 @@ const struct command_name *find_command_name(const char *name)
                else if (i > 0)
                        last = middle - 1;
                else
-                       return &command_names[middle];
+                       return middle;
        }
 
-       return NULL;
-}
-
-static const struct command_name *_find_command_name(const char *name)
-{
-       if (!islower(name[0]))
-               return NULL; /* Commands starts with lower-case */
-
-       return find_command_name(name);
+       return -1;
 }
 
-static const char *_is_command_name(char *str)
+const struct command_name *find_command_name(const char *name)
 {
-       const struct command_name *c;
-
-       if ((c = _find_command_name(str)))
-               return c->name;
+       int r = _find_lvm_command_enum(name);
 
-       return NULL;
+       return (r < LVM_COMMAND_COUNT) ? &command_names[r] : NULL;
 }
 
 static int _is_opt_name(char *str)
@@ -1306,6 +1295,7 @@ int define_commands(struct cmd_context *cmdtool, const char *run_name)
        int copy_pos = 0;
        int skip = 0;
        int i;
+       int lvm_command_enum;
 
        memset(&commands, 0, sizeof(commands));
 
@@ -1328,21 +1318,21 @@ int define_commands(struct cmd_context *cmdtool, const char *run_name)
                        continue;
 
                /* New cmd def begins: command_name <required opt/pos args> */
-               if ((name = _is_command_name(line_argv[0]))) {
-                       if (cmd_count >= COMMAND_COUNT) {
+               if (islower(line_argv[0][0]) && /* All commands are lower-case only */
+                   ((lvm_command_enum = _find_lvm_command_enum(line_argv[0])) < LVM_COMMAND_COUNT)) {
+                       if (cmd_count >= COMMAND_COUNT)
                                return 0;
-                       }
 
                        /*
                         * FIXME: when running one specific command name,
                         * we can optimize by not parsing command defs
                         * that don't start with that command name.
                         */
-
                        cmd = &commands[cmd_count];
                        cmd->command_index = cmd_count;
                        cmd_count++;
-                       cmd->name = name;
+                       cmd->lvm_command_enum = lvm_command_enum;
+                       cmd->name = name = command_names[lvm_command_enum].name;
 
                        if (run_name && strcmp(run_name, name)) {
                                skip = 1;
@@ -1724,8 +1714,8 @@ static void _print_usage_def(struct command *cmd, int opt_enum, struct arg_def *
 
 void print_usage(struct command *cmd, int longhelp, int desc_first)
 {
-       const struct command_name *cname = _find_command_name(cmd->name);
-       const struct command_name_args *cna = (cname) ? &command_names_args[cname->lvm_command_enum] : NULL;
+       const struct command_name *cname = &command_names[cmd->lvm_command_enum];
+       const struct command_name_args *cna = &command_names_args[cname->lvm_command_enum];
        int any_req = (cmd->cmd_flags & CMD_FLAG_ANY_REQUIRED_OPT) ? 1 : 0;
        int include_extents = 0;
        int ro, rp, oo, op, opt_enum, first;

diff --git a/tools/command.h b/tools/command.h
index b0492a316b6f601c86e1043b982485aa4c0e91e6..ef7a5d77cff39994ea6f692819f283d030746607 100644 (file)
--- a/tools/command.h
+++ b/tools/command.h
@@ -193,6 +193,7 @@ struct command {
        command_fn fn;                      /* old style */
 
        unsigned int cmd_flags; /* CMD_FLAG_ */
+       uint16_t lvm_command_enum; /* position in commands[] */
 
        /* definitions of opt/pos args */
 

diff --git a/tools/man-generator.c b/tools/man-generator.c
index 32fbd998263f94be43a7e3d8fdab4c26932412e9..bc2b1770b36cc0d579eadece48eb4d8d27726dad 100644 (file)
--- a/tools/man-generator.c
+++ b/tools/man-generator.c
@@ -346,8 +346,8 @@ static const char *_man_long_opt_name(const char *cmdname, int opt_enum)
 
 static void _print_man_usage(char *lvmname, struct command *cmd)
 {
-       const struct command_name *cname;
-       const struct command_name_args *cna;
+       const struct command_name *cname = &command_names[cmd->lvm_command_enum];
+       const struct command_name_args *cna = &command_names_args[cmd->lvm_command_enum];
        int any_req = (cmd->cmd_flags & CMD_FLAG_ANY_REQUIRED_OPT) ? 1 : 0;
        int sep, ro, rp, oo, op, opt_enum;
        int need_ro_indent_end = 0;
@@ -356,11 +356,6 @@ static void _print_man_usage(char *lvmname, struct command *cmd)
        uint64_t lv_type_bits = 0;
 
        _was_hyphen = 0;
-       if (!(cname = _find_command_name(cmd->name)))
-               return;
-
-       cna = &command_names_args[cname->lvm_command_enum];
-
        printf("\\fB%s\\fP", lvmname);
 
        if (!any_req)
@@ -712,12 +707,9 @@ out:
 
 static void _print_man_usage_common_lvm(struct command *cmd)
 {
-       const struct command_name *cname;
+       const struct command_name *cname = &command_names[cmd->lvm_command_enum];
        int i, sep, oo, opt_enum;
 
-       if (!(cname = _find_command_name(cmd->name)))
-               return;
-
        printf("Common options for lvm:\n");
        printf(".\n");
 
@@ -796,16 +788,11 @@ static void _print_man_usage_common_lvm(struct command *cmd)
 
 static void _print_man_usage_common_cmd(struct command *cmd)
 {
-       const struct command_name *cname;
-       const struct command_name_args *cna;
+       const struct command_name *cname = &command_names[cmd->lvm_command_enum];
+       const struct command_name_args *cna = &command_names_args[cmd->lvm_command_enum];
        int i, sep, oo, opt_enum;
        int found_common_command = 0;
 
-       if (!(cname = _find_command_name(cmd->name)))
-               return;
-
-       cna = &command_names_args[cname->lvm_command_enum];
-
        if (cna->variants < 2)
                return;
 
@@ -1369,7 +1356,7 @@ static int _print_man(char *name, char *des_file, int secondary)
                name += 4;
        }
 
-       cname = _find_command_name(name);
+       cname = find_command_name(name);
 
        printf(".TH %s 8 \"LVM TOOLS #VERSION#\" \"Red Hat, Inc.\"\n",
                _upper_command_name(lvmname));
@@ -1409,10 +1396,8 @@ static int _print_man(char *name, char *des_file, int secondary)
                        printf(".\n.SH SYNOPSIS\n.\n");
                        prev_cmd = cmd;
 
-                       if (!(cname = _find_command_name(cmd->name)))
-                               return 0;
-
-                       cna = &command_names_args[cname->lvm_command_enum];
+                       cname = &command_names[cmd->lvm_command_enum];
+                       cna = &command_names_args[cmd->lvm_command_enum];
 
                        if (cna->variant_has_ro && cna->variant_has_rp)
                                printf("\\fB%s\\fP \\fIoption_args\\fP \\fIposition_args\\fP\n", lvmname);