new shell

1 files changed, 98 insertions, 0 deletions

diff --git a/src/user/highway/vars.c b/src/user/highway/vars.c
new file mode 100644
index 0000000..6090b76
--- /dev/null
+++ b/src/user/highway/vars.c
@@ -0,0 +1,98 @@
+#include <knob/block.h>
+#include <knob/heap.h>
+#include <knob/user.h>
+
+struct no_null_sn {
+  char *data;
+  uint32_t length;
+};
+
+struct var_dict_node {
+  struct var_dict_node *next;
+  struct var_dict_node *prev;
+  struct no_null_sn name;
+  struct no_null_sn value;
+};
+
+static struct var_dict_node *var_dict_start = 0;
+
+__attribute__ ((pure))
+static struct var_dict_node *get_node(struct no_null_sn name) {
+  for (struct var_dict_node *i = var_dict_start; i; i = i->next)
+    if ((i->name.length == name.length) &&
+        blockequ(i->name.data, name.data, name.length))
+      return i;
+  return 0;
+}
+
+static struct var_dict_node *new_node() {
+  struct var_dict_node *node = get_block(sizeof(struct var_dict_node));
+  node->prev = 0;
+  node->next = var_dict_start;
+  if (var_dict_start)
+    var_dict_start->prev = node;
+  var_dict_start = node;
+  return node;
+}
+
+void set_var(struct no_null_sn name, struct no_null_sn value) {
+  struct var_dict_node *node = get_node(name);
+  if (node)
+    free_block(node->value.data);
+  else {
+    node = new_node();
+    node->name.length = name.length;
+    node->name.data = get_block(name.length);
+    blockcpy(node->name.data, name.data, name.length);
+  }
+  node->value.length = value.length;
+  node->value.data = get_block(value.length);
+  blockcpy(node->value.data, value.data, value.length);
+}
+
+__attribute__ ((pure))
+const struct no_null_sn *get_var(struct no_null_sn name) {
+  struct var_dict_node *node = get_node(name);
+  return node ? &node->value : 0;
+}
+
+void del_var(struct no_null_sn name) {
+  struct var_dict_node *node = get_node(name);
+  if (!node)
+    return;
+  free_block(node->name.data);
+  free_block(node->value.data);
+  if (node->prev)
+    node->prev->next = node->next;
+  if (node->next)
+    node->next->prev = node->prev;
+  if (node == var_dict_start)
+    var_dict_start = node->next;
+  free_block(node);
+}
+
+void dump_vars() {
+  for (struct var_dict_node *node = var_dict_start; node; node = node->next) {
+    tell_user_sz("$");
+
+    char *buf = get_block(node->name.length + 1);
+    blockcpy(buf, node->name.data, node->name.length);
+    buf[node->name.length] = '\0';
+
+    tell_user_sz(buf);
+
+    free_block(buf);
+
+    tell_user_sz("$ = ");
+
+    buf = get_block(node->value.length + 1);
+    blockcpy(buf, node->value.data, node->value.length);
+    buf[node->value.length] = '\0';
+
+    tell_user_sz(buf);
+
+    free_block(buf);
+
+    tell_user_sz("\n");
+  }
+}
\ No newline at end of file