new shell

8 files changed, 290 insertions, 24 deletions

diff --git a/src/user/highway/cmds.c b/src/user/highway/cmds.c
new file mode 100644
index 0000000..d7a89d1
--- /dev/null
+++ b/src/user/highway/cmds.c
@@ -0,0 +1,46 @@
+#include <knob/file.h>
+#include <knob/user.h>
+#include "line.h"
+#include "vars.h"
+
+void source(const char *path) {
+  struct file *f = open_file(path);
+  if (!f)
+    tell_user_sz("couldn't open file.\n");
+  char buf[128];
+  while (read_line_from_file(f, buf, 127))
+    run_line(buf);
+  close_file(f);
+}
+
+void set(const char *arg) {
+  const char *space = arg;
+  while (*space != ' ')
+    if (*space)
+      ++space;
+    else {
+      struct no_null_sn vname = {
+        .data = arg,
+        .length = space - arg
+      };
+      del_var(vname);
+      return;
+    }
+
+  struct no_null_sn vname = {
+    .data = arg,
+    .length = space - arg
+  };
+
+  const char *vstart = space + 1,
+             *vend = vstart;
+  while (*vend)
+    ++vend;
+  
+  struct no_null_sn vval = {
+    .data = vstart,
+    .length = vend - vstart
+  };
+
+  set_var(vname, vval);
+}
\ No newline at end of file
diff --git a/src/user/highway/cmds.h b/src/user/highway/cmds.h
new file mode 100644
index 0000000..c404d40
--- /dev/null
+++ b/src/user/highway/cmds.h
@@ -0,0 +1,7 @@
+#ifndef CMDS_H
+#define CMDS_H
+
+void source(const char *path);
+void set(const char *arg);
+
+#endif
\ No newline at end of file
diff --git a/src/user/highway/highway.c b/src/user/highway/highway.c
deleted file mode 100644
index 7e78472..0000000
--- a/src/user/highway/highway.c
+++ /dev/null
@@ -1,24 +0,0 @@
-#include <knob/user.h>
-#include <knob/task.h>
-#include <knob/block.h>
-
-//TODO: load a user environment file containing a PATH-like setting.
-//TODO: have an active disk and/or directory
-
-void main() {
-  char path_buf[1024 + 4] = "bin/";
-  char *const line_buf = path_buf + 4;
-
-  tell_user_sz("Highway, Portland Command Shell, started.\n"
-               "Type \"exit\" to quit.\n");
-  yield_task();
-
-  while (1) {
-    tell_user_sz("> ");
-    ask_user_line_sz(line_buf, 1023);
-    if (blockequ(line_buf, "exit", 5))
-      return;
-    if (!try_run_command_blocking(path_buf))
-      tell_user_sz("An error occured trying to run that command.\n");
-  }
-}
\ No newline at end of file
diff --git a/src/user/highway/line.c b/src/user/highway/line.c
new file mode 100644
index 0000000..ca38c9b
--- /dev/null
+++ b/src/user/highway/line.c
@@ -0,0 +1,100 @@
+#include <knob/block.h>
+#include <knob/quit.h>
+#include <knob/task.h>
+#include <knob/user.h>
+#include "cmds.h"
+#include "vars.h"
+
+#define LINE_SIZE 4096
+static char line[LINE_SIZE];
+
+static void line_replace(const char *from) {
+  const char *fi = from;
+  char *ti = line;
+  while (*fi) {
+    if (ti == line + LINE_SIZE) {
+      tell_user_sz("Line too long.\n");
+      line[0] = '\0';
+      return;
+    }
+    if (*fi != '$') {
+      *ti = *fi;
+      ++ti;
+      ++fi;
+      continue;
+    }
+    const char *var_start = ++fi;
+    const char *var_end = var_start;
+    while (*var_end != '$')
+      if (!*var_end++) {
+        tell_user_sz("Unterminated variable name.\n");
+        line[0] = '\0';
+        return;
+      }
+    if (ti + (var_end - var_start) >= line + LINE_SIZE) {
+      tell_user_sz("Line too long.\n");
+      line[0] = '\0';
+      return;
+    }
+    struct no_null_sn vname = {
+      .data = var_start,
+      .length = var_end - var_start
+    };
+    const struct no_null_sn *vval = get_var(vname);
+    if (!vval)
+      vval = &vname;
+    blockcpy(ti, vval->data, vval->length);
+    ti += vval->length;
+    fi = var_end + 1;
+  }
+  *ti = '\0';
+}
+
+void run_line(const char *original_line) {
+  line_replace(original_line);
+  if (!*line)
+    return;
+  const char *space;
+  for (space = line; *space && (*space != ' '); ++space)
+    ;
+  if (blockequ(line, "source", space - line))
+    source(space + 1);
+  else if (blockequ(line, "set", space - line))
+    set(space + 1);
+  else if (blockequ(line, "echo", space - line)) {
+    tell_user_sz(space + 1);
+    tell_user_sz("\n");
+  }
+  else if (blockequ(line, "vars", space - line))
+    dump_vars();
+  else if (blockequ(line, "quit", space - line))
+    quit(space + 1);
+  else if (blockequ(line, "help", space - line))
+    tell_user_sz("Highway is a command shell for Portland OS. It includes variables and a couple\n"
+                 "of pseudo-commands. Variables are addressed by surrounding with \"$\". The\n"
+                 "following list shows each of the pseudo-commands.\n\n"
+                 "  source FILE       run each command in FILE\n"
+                 "  set VAR VALUE     set $VAR$ to VALUE\n"
+                 "  echo STRING       print STRING\n"
+                 "  vars              dump variables\n"
+                 "  quit              exit highway\n"
+                 "  help              show this\n\n");
+  else if (!try_run_command_blocking(line)) {
+    struct no_null_sn arg = {
+      .data = "_path",
+      .length = 5
+    };
+    const struct no_null_sn *path = get_var(arg);
+    if (!path->length) {
+      tell_user_sz("Could not run command.\n");
+      return;
+    }
+    for (uint16_t to_i = LINE_SIZE - 1; to_i >= path->length; --to_i)
+      line[to_i] = line[to_i - path->length];
+    blockcpy(line, path->data, path->length);
+    if (!try_run_command_blocking(line)) {
+      tell_user_sz("Could not run command.\n");
+      return;
+    }
+  }
+}
\ No newline at end of file
diff --git a/src/user/highway/line.h b/src/user/highway/line.h
new file mode 100644
index 0000000..4785034
--- /dev/null
+++ b/src/user/highway/line.h
@@ -0,0 +1,6 @@
+#ifndef LINE_H
+#define LINE_H
+
+void run_line(const char *line);
+
+#endif
\ No newline at end of file
diff --git a/src/user/highway/main.c b/src/user/highway/main.c
new file mode 100644
index 0000000..1934920
--- /dev/null
+++ b/src/user/highway/main.c
@@ -0,0 +1,16 @@
+#include <knob/user.h>
+#include <knob/task.h>
+#include "cmds.h"
+#include "line.h"
+
+void main(const char *arg) {
+  source(*arg ? arg : "user/default.rc");
+  char cmd_buf[128];
+  yield_task();
+  tell_user_sz("Portland Highway\nType \"help\" for help.\n");
+  while (1) {
+    tell_user_sz("> ");
+    ask_user_line_sz(cmd_buf, 127);
+    run_line(cmd_buf);
+  }
+}
\ No newline at end of file
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
diff --git a/src/user/highway/vars.h b/src/user/highway/vars.h
new file mode 100644
index 0000000..fc4d197
--- /dev/null
+++ b/src/user/highway/vars.h
@@ -0,0 +1,17 @@
+#ifndef VARS_H
+#define VARS_H
+
+#include <stdint.h>
+
+struct no_null_sn {
+  const char *data;
+  uint32_t length;
+};
+
+void set_var(struct no_null_sn name, struct no_null_sn value);
+const struct no_null_sn *get_var(struct no_null_sn name) __attribute__ ((pure));
+void del_var(struct no_null_sn name);
+
+void dump_vars();
+
+#endif
\ No newline at end of file