IMplement help system. Though it need refactoring.

src/cmd/cmd.c

@@ -68,11 +68,12 @@ struct UCCmdNode {
     union {
         struct UCCmdWord word;
         struct UCCmdList list;
-        struct UCCmdDef *cmd;
+        const struct UCCmdDef *cmd;
     } data;
     uint32_t flags;
     struct UCCmdNode *next; //next at same level
     struct UCCmdNode *child;
+    struct UCCmdNode *parent;
 };
 
 struct UCCmdRunner {
@@ -99,17 +100,21 @@ struct UCCmdTokenizer {
 
 struct UCCmdArgs {
     struct UCStrv argv;
-    struct UCCmdDef *cmd;
+    const struct UCCmdDef *cmd;
 };
 
-void print_args(const struct UCStrv *args);
+void 
-static int uc_cmd_type_is_variable(enum UCCmdType type)
+print_args(const struct UCStrv *args);
+
+static int 
+uc_cmd_type_is_variable(enum UCCmdType type)
 {
     return type == UC_CMD_LIST ||
            type == UC_CMD_STRING;
 }
 
-static void uc_cmd_tokenize(struct UCCmdTokenizer *t, const char *cmd, const char *delim)
+static void 
+uc_cmd_tokenize(struct UCCmdTokenizer *t, const char *cmd, const char *delim)
 {
     
     t->num_words = 0;
@@ -144,13 +149,14 @@ uc_cmd_runner_init(struct UCCmdRunner *r)
 {
     memset(r, 0, sizeof *r);
     r->root_node = &r->_root;
-    r->_root.type = UC_CMD_KEYWORD;
+    r->_root.type = UC_CMD_ROOT;
 }
 
 void
 uc_cmd_node_dealloc(struct UCCmdNode *n)
 {
     struct UCCmdNode *next;
+
     while (n) {
         uc_cmd_node_dealloc(n->child); 
         next = n->next;
@@ -281,6 +287,7 @@ uc_cmd_add(struct UCCmdNode *parent, const char *word)
     if (new_node == NULL) {
         return NULL;
     }
+    new_node->parent = parent;
 
     while (*iter) {
         struct UCCmdNode *n = *iter;
@@ -304,12 +311,80 @@ uc_cmd_add(struct UCCmdNode *parent, const char *word)
    return new_node;
 }
 
+static int uc_cmd_node_add_help(struct UCCmdNode *node)
+{
+    struct UCCmdTokenizer t;
+    int i;
+
+    if (node->data.cmd->help == NULL) {
+        //allow helpless commands
+        return 0;
+    }
+
+    if (node->type != UC_CMD_END) {
+        return -10;
+    }
+
+    uc_cmd_tokenize(&t, node->data.cmd->help, "\n");
+    if (t.num_words <= 0) {
+        uc_cmd_tokenize_destroy(&t);
+        return -11;
+    }
+
+    i = t.num_words - 1;
+    //we have the last node in the tree
+    //Walk it up towards the root(backwards) and fill
+    //in help texts where it's missing.
+    while (node->parent) {
+
+        node = node->parent;
+        if (node->type == UC_CMD_ROOT) {
+            break;
+        }
+        if (i < 0) {
+            break;
+        }
+
+        if (node->type == UC_CMD_KEYWORD || 
+            node->type == UC_CMD_STRING) {
+            if (node->data.word.descr == NULL) {
+                node->data.word.descr = strdup(t.cmd_words[i]);
+            }
+            i--;
+        } else if (node->type == UC_CMD_LIST) {
+            if (node->data.list.descrs.cnt == 0) {
+                for (int k = (int)node->data.list.words.cnt -1; k >= 0; k++) {
+                    if (i < 0) {
+                        break;
+                    }
+                    uc_strv_append(&node->data.list.descrs, t.cmd_words[i]);
+                    i--;
+
+                }
+            } else {
+                i -= (int)node->data.list.words.cnt;
+            }
+        }
+    }
+
+    uc_cmd_tokenize_destroy(&t);
+
+    if (node->type != UC_CMD_ROOT || i != -1) {
+        //we didn't consume all the help tokens, so the 
+        //command definition is screwd up
+        return -20;
+    }
+   
+    return 0;
+}
+
 int
 uc_cmd_install_noassert(struct UCCmdRunner *r, struct UCCmdDef *cmd)
 {
     struct UCCmdNode *node = r->root_node;
     struct UCCmdNode *new_node; 
     struct UCCmdTokenizer t;
+    int rc;
 
     uc_cmd_tokenize(&t, cmd->cmd, NULL);
     if (t.num_words <= 0) {
@@ -333,13 +408,15 @@ uc_cmd_install_noassert(struct UCCmdRunner *r, struct UCCmdDef *cmd)
         return -1;
     }
     new_node->data.cmd = cmd;
-    new_node->next = node->child;
+    new_node->next     = node->child;
-    node->child = new_node;
+    node->child        = new_node;
+    new_node->parent   = node;
 
+    rc = uc_cmd_node_add_help(new_node);
 
     uc_cmd_tokenize_destroy(&t);
 
-    return 0;
+    return rc;
 }
 
 int
@@ -360,11 +437,11 @@ uc_cmd_find(struct UCCmdNode *first,
             struct UCCmdNode **result)
 {
     struct UCCmdNode *node = first;
+    struct UCCmdNode *found = NULL;
     enum UCCmdRc rc = UC_CMDRC_NOT_FOUND;
 
     for (int i = 0; i < t->num_words && node; i++) {
         int n_found = 0;
-        struct UCCmdNode *found = NULL;
 
         while (node) {
             if (uc_cmd_node_match(node, t->cmd_words[i], args)) {
@@ -387,9 +464,9 @@ uc_cmd_find(struct UCCmdNode *first,
         }
     }
 
-    *result = node;
+    *result = found;
 
-    if (node == NULL) {
+    if (found == NULL) {
         rc = UC_CMDRC_NOT_FOUND;
     }
 
@@ -423,42 +500,57 @@ uc_cmd_parse_and_find(struct UCCmdRunner *r, const char *cmd_line,
 }
 
 enum UCCmdRc
-uc_cmd_complete(struct UCCmdRunner *r, const char *cmd_line)
+uc_cmd_help(struct UCCmdRunner *r, const char *cmd_line, struct UCStrv *completions)
 {
+    struct UCCmdNode *found = NULL;
+    enum UCCmdRc rc;
 
-    struct UCStrv completions = UC_STRV_INITIALIZER;
+    rc = uc_cmd_parse_and_find(r, cmd_line, NULL, &found);
+    if (rc == UC_CMDRC_OK) {
+        struct UCCmdNode *node = found;
 
+        if (node->type == UC_CMD_LIST) {
+            uc_strv_append_all(completions, &node->data.list.descrs, 1);
+        } else if (node->type == UC_CMD_STRING || 
+                   node->type == UC_CMD_KEYWORD) {
+            if (node->data.word.descr != NULL) {
+                uc_strv_append(completions, node->data.word.descr);
+            }
+        }
+    } 
+
+    return rc;
+}
+
+enum UCCmdRc
+uc_cmd_complete(struct UCCmdRunner *r, const char *cmd_line, struct UCStrv *completions)
+{
     struct UCCmdNode *found = NULL;
     enum UCCmdRc rc;
 
     rc = uc_cmd_parse_and_find(r, cmd_line, NULL, &found);
     if (rc != UC_CMDRC_NOT_FOUND && found != NULL) {
-        struct UCCmdNode *node = found;
+        struct UCCmdNode *node = found->child;
+
         while (node) {
             if (node->type == UC_CMD_END) {
-                uc_strv_append(&completions, "<CR>");
+                uc_strv_append(completions, "<CR>");
             } else if (node->type == UC_CMD_LIST) {
-                uc_strv_append_all(&completions, &node->data.list.words, 1);
+                uc_strv_append_all(completions, &node->data.list.words, 1);
             } else if (node->type == UC_CMD_STRING || 
                        node->type == UC_CMD_KEYWORD) {
-                uc_strv_append(&completions, node->data.word.word);
+                uc_strv_append(completions, node->data.word.word);
             }
             node = node->next;
         }
 
-        printf("Possible completions for '%s'\n", cmd_line);
+    } 
-        print_args(&completions);
 
-    } else {
-        printf("No possible completions\n");
-    }
-
-    uc_strv_destroy(&completions);
-    
     return rc;
 }
 
 
+
 enum UCCmdRc
 uc_cmd_run(struct UCCmdRunner *r, const char *cmd_line)
 {
@@ -472,6 +564,7 @@ uc_cmd_run(struct UCCmdRunner *r, const char *cmd_line)
 
     rc = uc_cmd_parse_and_find(r, cmd_line, &args.argv, &found);
     if (rc == UC_CMDRC_OK) {
+        found = found->child;
         // Now check the current level for any UC_CMD_END
         // which indicates a complete command
         while (found) {
@@ -482,7 +575,7 @@ uc_cmd_run(struct UCCmdRunner *r, const char *cmd_line)
         }
 
         if (found != NULL) {
-            struct UCCmdDef *cmd = found->data.cmd;
+            const struct UCCmdDef *cmd = found->data.cmd;
             args.cmd = cmd;
             rc = cmd->callback(&args);
         } else {
@@ -536,8 +629,39 @@ enum UCCmdRc cmd4_cb(const struct UCCmdArgs *args)
     return UC_CMDRC_OK;
 }
 
+void do_complete(struct UCCmdRunner *r, const char *command)
+{
+    struct UCStrv completions = UC_STRV_INITIALIZER;
 
+    uc_cmd_complete(r, command, &completions);
+    if (completions.cnt > 0) {
+        printf("Possible completions for '%s' :\n", command);
+        for (size_t i = 0; i < completions.cnt; i++) {
+            printf("\t%s\n", completions.strings[i]);
+        }
+    } else {
+        printf("No completions for '%s' :\n", command);
+    }
 
+    uc_strv_destroy(&completions);
+}
+
+void do_help(struct UCCmdRunner *r, const char *command)
+{
+    struct UCStrv completions = UC_STRV_INITIALIZER;
+
+    uc_cmd_help(r, command, &completions);
+    if (completions.cnt > 0) {
+        printf("help for '%s' :\n", command);
+        for (size_t i = 0; i < completions.cnt; i++) {
+            printf("\t%s\n", completions.strings[i]);
+        }
+    } else {
+        printf("No help for '%s' :\n", command);
+    }
+
+    uc_strv_destroy(&completions);
+}
 
 
 int main(int argc, char *argv[])
@@ -546,7 +670,7 @@ int main(int argc, char *argv[])
     struct UCCmdRunner r;
     struct UCCmdDef cmd1 = {
         "show all",
-        "\n\n",
+        " \nEverything\n",
         cmd1_cb, 
         0,
         NULL
@@ -554,7 +678,7 @@ int main(int argc, char *argv[])
 
     struct UCCmdDef cmd2 = {
         "show empty",
-        "\n\n",
+        "Show parameter\nAll empty\n",
         cmd2_cb, 
         0,
         NULL
@@ -562,7 +686,7 @@ int main(int argc, char *argv[])
 
     struct UCCmdDef cmd3 = {
         "show empty bottle",
-        "\n\n\n",
+        NULL,
         cmd3_cb, 
         0,
         NULL
@@ -570,7 +694,7 @@ int main(int argc, char *argv[])
 
     struct UCCmdDef cmd4 = {
         "delete file NAME",
-        "\n\nName of the file\n",
+        "delete\nfile\nName of the file\n",
         cmd4_cb, 
         0,
         NULL
@@ -587,6 +711,12 @@ int main(int argc, char *argv[])
     uc_cmd_run(&r, "show empty");
     uc_cmd_run(&r, "sh emp b");
     uc_cmd_run(&r, "");
+
+    do_help(&r, "delete file /tmp/a");
+    do_help(&r, "show empty");
+    do_help(&r, "show all");
+    do_help(&r, "sh");
+    do_help(&r, "");
     /*
     while (fgets(line,sizeof line, stdin)) {
         enum UCCmdRc rc = uc_cmd_run(&r, line);
@@ -596,9 +726,13 @@ int main(int argc, char *argv[])
     }
     */
 
-    uc_cmd_complete(&r, "sho em");
+    do_complete(&r, "sho em");
-    uc_cmd_complete(&r, "show  ");
+    do_complete(&r, "show  ");
-    uc_cmd_complete(&r, "");
+    do_complete(&r, "");
+    do_complete(&r, "delet ");
+    do_complete(&r, "delete ");
+    do_complete(&r, "delete file");
+    do_complete(&r, "delete fil");
     uc_cmd_runner_destroy(&r);