Add command parsing and echo commandadd-shell

6 files changed, 146 insertions, 11 deletions

diff --git a/os/commands/echo.c b/os/commands/echo.c
new file mode 100644
index 0000000..669003e
--- /dev/null
+++ b/os/commands/echo.c
@@ -0,0 +1,5 @@
+#include "../../kernel/gpu/text_mode/display.h"
+
+void echo(char *args) {
+  scrn_println(args);
+}
\ No newline at end of file
diff --git a/os/commands/echo.h b/os/commands/echo.h
new file mode 100644
index 0000000..db62a4f
--- /dev/null
+++ b/os/commands/echo.h
@@ -0,0 +1 @@
+void echo(char *args);
\ No newline at end of file
diff --git a/os/main.c b/os/main.c
index b04ee62..3e71c1e 100644
--- a/os/main.c
+++ b/os/main.c
@@ -57,6 +57,21 @@ void os_update_infobar_rc()
   scrn_set_cursor_pos(curr_r, curr_c);
 }
 
+void os_update_infobar_program() {
+  int curr_attr_byte = scrn_get_char_attr_byte();
+  int curr_r = scrn_get_cursor_row();
+  int curr_c = scrn_get_cursor_col();
+
+  scrn_set_text_colour(COLOUR_WHITE, COLOUR_BLUE);
+  scrn_set_cursor_pos(0, 11);
+  line_pad(64);
+  scrn_set_cursor_pos(0, 11);
+  scrn_print(focused_program.name);
+
+  scrn_set_char_attr_byte(curr_attr_byte);
+  scrn_set_cursor_pos(curr_r, curr_c);
+}
+
 void os_init_infobar()
 {
   scrn_clear();
@@ -64,9 +79,7 @@ void os_init_infobar()
   scrn_set_text_colour(COLOUR_WHITE, COLOUR_BLUE);
   line_pad(80); // fill line
   scrn_set_cursor_pos(0, 2);
-  scrn_print("tinyOS");
-  scrn_set_cursor_pos(0, 30);
-  scrn_print("running: ");
+  scrn_print("tinyOS - ");
   scrn_print(focused_program.name);
   
   os_update_infobar_rc();
@@ -77,6 +90,7 @@ void os_init_infobar()
 // TODO keep a stack of running programs
 void os_update_focused_program(Program_t program) {
   focused_program = program;
+  os_update_infobar_program();
 }
 
 // Send keypress from kernel to the currently focused programs keypress handler
@@ -87,11 +101,11 @@ void os_proxy_keypress(unsigned char key) {
 
 void os_start()
 {
-  os_update_focused_program(shell_run());
   scrn_enable_cursor(10, 12);
   os_init_infobar();
   os_show_splash();
-  os_update_infobar_rc();
-}
+  
+  os_update_focused_program(shell_run());
 
-// TODO display handling
\ No newline at end of file
+  os_update_infobar_rc();
+}
\ No newline at end of file
diff --git a/os/shell/shell.c b/os/shell/shell.c
index 933b19c..4fb5488 100644
--- a/os/shell/shell.c
+++ b/os/shell/shell.c
@@ -1,17 +1,116 @@
 #include "../../os/main.h"
 #include "../../kernel/gpu/text_mode/display.h"
+#include "../stdlib/sdtlib.h"
+#include "../commands/echo.h"
+
+#define CMD_BUFFER_SIZE 80
+
+// TODO history buffer
+unsigned char cmd_buffer[CMD_BUFFER_SIZE];
+int cmd_buffer_p = 0;
+
+// cant malloc yet so just store locally
+unsigned char cmd[CMD_BUFFER_SIZE];
+unsigned char args[CMD_BUFFER_SIZE];
+
+void shell_set_prompt() {
+  scrn_print("$> ");
+}
+
+void shell_clear_cmd_buffer() {
+  for(int i = 0; i < CMD_BUFFER_SIZE; i++) {
+    cmd_buffer[i] = 0;
+  }
+  cmd_buffer_p = 0;
+}
+
+void shell_clear_cmd() {
+  for(int i = 0; i < CMD_BUFFER_SIZE; i++) {
+    cmd[i] = 0;
+  }
+}
+
+void shell_clear_args() {
+  for(int i = 0; i < CMD_BUFFER_SIZE; i++) {
+    args[i] = 0;
+  }
+}
+
+unsigned char* shell_parse_cmd() {
+  shell_clear_cmd();
+  for(int i = 0; i < CMD_BUFFER_SIZE; i++) {
+    if (cmd_buffer[i] == ' ') {
+      break;
+    }
+    cmd[i] = cmd_buffer[i];
+  }
+  return cmd;
+}
+
+unsigned char* shell_parse_args() {
+  shell_clear_args();
+  int arg_idx = 0;
+  for(int i = 0; i < CMD_BUFFER_SIZE; i++) {
+    if (cmd_buffer[i] == ' ') {
+      arg_idx = i + 1;
+      break;
+    }
+  }
+
+  if (arg_idx == 0) {
+    return args;
+  }
+  else {
+    for(int i = arg_idx; i < CMD_BUFFER_SIZE; i++) {
+      args[i - arg_idx] = cmd_buffer[i];
+    }
+    return args;
+  }
+}
+
+void shell_exec_cmd(unsigned char* cmd_name, unsigned char* args) {
+  // TODO lookup string to funciton pointer
+  if (strcmp(cmd_name, "echo") == 0) {
+    echo(args);
+  }
+  else if (strcmp(cmd_name, "") != 0) {
+    scrn_print(cmd_name);
+    scrn_println(": command not found");
+  }
+}
+
+void shell_process_cmd_buffer() {
+  scrn_newline();
+
+  shell_exec_cmd(shell_parse_cmd(), shell_parse_args());
+
+  shell_clear_cmd_buffer();
+  shell_set_prompt();  
+}
+
+void shell_handle_backspace() {
+  if (cmd_buffer_p != 0) {
+    cmd_buffer[--cmd_buffer_p] = 0;
+    scrn_backspace();
+  }
+}
+
+void shell_handle_keypress(unsigned char key) {
+  cmd_buffer[cmd_buffer_p++] = key;
+  scrn_putchar(key);
+}
 
 void keypress_handler(unsigned char key) {
   switch(key)
     {
       case '\b':
-        scrn_backspace();
+        shell_handle_backspace();
         break;
       case '\n':
-        scrn_newline();
+        shell_process_cmd_buffer();
         break;
       default:
-        scrn_putchar(key);
+        shell_handle_keypress(key);
     }
 }
 
@@ -19,5 +118,6 @@ Program_t shell_run() {
   Program_t this;
   this.keypress_handler = keypress_handler;
   this.name = "shell";
+  shell_set_prompt();
   return this;
 }
\ No newline at end of file
diff --git a/os/stdlib/sdtlib.h b/os/stdlib/sdtlib.h
index a0b3402..85073d2 100644
--- a/os/stdlib/sdtlib.h
+++ b/os/stdlib/sdtlib.h
@@ -1 +1,2 @@
-char* int_to_str(int i);
\ No newline at end of file
+char* int_to_str(int i);
+int strcmp(const char *str1, const char *str2);
\ No newline at end of file
diff --git a/os/stdlib/stdlib.c b/os/stdlib/stdlib.c
index 465e978..bdb2242 100644
--- a/os/stdlib/stdlib.c
+++ b/os/stdlib/stdlib.c
@@ -18,4 +18,18 @@ char* int_to_str(int i)
     *--p = '-';
   }
   return p;
+}
+
+
+int strcmp(const char *str1, const char *str2)
+{
+	while(*str1){
+		if (*str1 != *str2) {
+	    break;
+    }
+		str1++;
+		str2++;
+	}
+
+	return *(const unsigned char*)str1 - *(const unsigned char*)str2;
 }
\ No newline at end of file