Add subprocesses and convert terminal to an app

2026-06-17 21:20:14 +03:00
parent 1c935cf154
commit 03b3ddac73
28 changed files with 490 additions and 247 deletions
@@ -0,0 +1,13 @@
+#include "src/lib/string.h"
+#include "src/user/syscall.h"
+
+int main(uint64_t argc, const char **argv) {
+  for (uint64_t i = 1; i < argc; i++) {
+    if (i > 1) {
+      write(1, " ", 1);
+    }
+    write(1, argv[i], string_length(argv[i]));
+  }
+  write(1, "\n", 1);
+  return 0;
+}
@@ -1,6 +0,0 @@
-#include "src/user/syscall.h"
-
-int main() {
-  write(1, "Hello from C!\n", 14);
-  return 0;
-}
@@ -0,0 +1,277 @@
+#include "src/lib/memory.h"
+#include "src/lib/string.h"
+#include "src/user/syscall.h"
+#include <stdint.h>
+
+static void help(uint8_t argc, char **argv);
+static void cd(uint8_t argc, char **argv);
+
+#define WRITE_S(s) write(1, s, sizeof(s) - 1);
+#define WRITE_D(s) write(1, s, string_length(s));
+
+#define PROMPT_LENGTH 255
+
+static const char bs[PROMPT_LENGTH + 1];
+static const char ws[PROMPT_LENGTH + 1];
+
+static char prompt[PROMPT_LENGTH + 1];
+static uint8_t prompt_length = 0;
+static uint8_t prompt_offset = 0;
+
+typedef void (*app_t)(uint8_t argc, char **argv);
+
+typedef struct {
+  const char *name;
+  app_t app;
+} app_entry_t;
+
+static app_entry_t builtins[] = {
+    {"help", help},
+    {"cd", cd},
+};
+
+static void help(uint8_t argc, __attribute__((unused)) char **argv) {
+  if (argc) {
+    WRITE_S("help: expects no arguments");
+    return;
+  }
+
+  WRITE_S("Available commands:\n");
+  for (uint64_t i = 0; i < sizeof(builtins) / sizeof(app_entry_t); i++) {
+    WRITE_D(builtins[i].name);
+    WRITE_S("\n");
+  }
+}
+
+static void cd(uint8_t argc, char **argv) {
+  if (argc != 2) {
+    WRITE_S("cd: requires a single path\n");
+    return;
+  }
+
+  if (chdir(argv[1]) == (uint64_t)-1) {
+    WRITE_S("cd: path does not exist\n");
+  }
+}
+
+static void print_prompt() {
+  char path[PROMPT_LENGTH];
+  uint8_t pl = getcwd(PROMPT_LENGTH, path);
+  char *components[16];
+  uint8_t cl = string_split(path, '/', 16, components);
+
+  WRITE_S("[")
+  WRITE_D(pl == 1 ? "/" : components[cl - 1]);
+  WRITE_S("]$ ");
+}
+
+static void on_home_pressed() {
+  if (!prompt_offset) {
+    return;
+  }
+
+  write(1, bs, prompt_offset);
+  prompt_offset = 0;
+}
+
+static void on_left_pressed() {
+  if (!prompt_offset) {
+    return;
+  }
+
+  write(1, bs, 1);
+  prompt_offset--;
+}
+
+static void on_right_pressed() {
+  if (prompt_offset == prompt_length) {
+    return;
+  }
+
+  write(1, prompt + prompt_offset, 1);
+  prompt_offset++;
+}
+
+static void on_end_pressed() {
+  if (prompt_offset == prompt_length) {
+    return;
+  }
+
+  write(1, prompt + prompt_offset, prompt_length - prompt_offset);
+  prompt_offset = prompt_length;
+}
+
+static void on_enter_pressed() {
+  prompt[prompt_length] = '\0';
+
+  char *argv[16];
+  uint8_t argc = (uint8_t)string_split(prompt, ' ', 16, argv);
+
+  WRITE_S("\n");
+
+  uint8_t i;
+  for (i = 0; i < sizeof(builtins) / sizeof(app_entry_t); i++) {
+    if (string_equal(argv[0], builtins[i].name)) {
+      builtins[i].app(argc, argv);
+      break;
+    }
+  }
+  if (i == sizeof(builtins) / sizeof(app_entry_t)) {
+    if (spawn(argv[0], argc, (const char **)argv) == (uint64_t)-1){
+      WRITE_S("terminal: program not found\n");
+    }
+  }
+  prompt_length = prompt_offset = 0;
+  print_prompt();
+}
+
+static void on_cancel_pressed() {
+  WRITE_S("^C\n");
+  prompt_length = prompt_offset = 0;
+  print_prompt();
+}
+
+static void on_disconnect_pressed() {
+  WRITE_S("^D\n");
+  exit();
+}
+
+static void on_ctrl_character_pressed(char c) {
+  if (c == 'c') {
+    on_cancel_pressed();
+  } else if (c == 'd') {
+    on_disconnect_pressed();
+  }
+}
+
+static void redraw_from_cursor() {
+  uint64_t tail = prompt_length - prompt_offset;
+  write(1, prompt + prompt_offset, tail);
+  write(1, ws, 1);        // erase the character past the end
+  write(1, bs, tail + 1); // move back to cursor position
+}
+
+static void on_character_pressed(char c) {
+  if (prompt_offset >= PROMPT_LENGTH)
+    return;
+
+  if (prompt_offset != prompt_length) {
+    memory_move(prompt + prompt_offset, prompt_length - prompt_offset, prompt + prompt_offset + 1);
+  }
+  prompt[prompt_offset] = c;
+  prompt_length++;
+  prompt_offset++;
+
+  write(1, &c, 1); // emit the character itself
+  redraw_from_cursor();
+}
+
+static void on_backspace_pressed() {
+  if (!prompt_offset)
+    return;
+
+  if (prompt_offset != prompt_length) {
+    memory_move(prompt + prompt_offset, prompt_length - prompt_offset, prompt + prompt_offset - 1);
+  }
+  prompt_offset--;
+  prompt_length--;
+
+  write(1, bs, 1);
+  redraw_from_cursor();
+}
+
+static void on_delete_pressed() {
+  if (prompt_offset == prompt_length)
+    return;
+
+  memory_move(prompt + prompt_offset + 1, prompt_length - prompt_offset - 1, prompt + prompt_offset);
+  prompt_length--;
+
+  redraw_from_cursor();
+}
+
+typedef enum {
+  PARSE_NORMAL,
+  PARSE_ESC,
+  PARSE_CSI,
+} parse_state_t;
+
+static parse_state_t parser_state = PARSE_NORMAL;
+static char parser_csi_param[8];
+static uint8_t parser_csi_len;
+
+static void on_char_received(char c) {
+  switch (parser_state) {
+  case PARSE_NORMAL:
+    if (c == '\x1B') {
+      parser_state = PARSE_ESC;
+    } else if (c == '\b' || c == '\x7F') {
+      on_backspace_pressed();
+    } else if (c == '\n' || c == '\r') {
+      on_enter_pressed();
+    } else if (c >= '\x01' && c <= '\x1A') {
+      on_ctrl_character_pressed(c + 'a' - 1);
+    } else if (c >= ' ') {
+      on_character_pressed(c);
+    }
+    break;
+
+  case PARSE_ESC:
+    if (c == '[') {
+      parser_state = PARSE_CSI;
+      parser_csi_len = 0;
+    } else {
+      parser_state = PARSE_NORMAL;
+    }
+    break;
+
+  case PARSE_CSI:
+    if ((c >= '0' && c <= '9') || c == ';') {
+      if (parser_csi_len < sizeof(parser_csi_param) - 1) {
+        parser_csi_param[parser_csi_len++] = c;
+      }
+    } else {
+      parser_state = PARSE_NORMAL;
+      parser_csi_param[parser_csi_len] = '\0';
+
+      switch (c) {
+      case 'C':
+        on_right_pressed();
+        break;
+      case 'D':
+        on_left_pressed();
+        break;
+      case 'H':
+        on_home_pressed();
+        break;
+      case 'F':
+        on_end_pressed();
+        break;
+      case '~':
+        if (parser_csi_param[0] == '3') {
+          on_delete_pressed();
+        }
+        break;
+      }
+    }
+    break;
+  }
+}
+
+int main() {
+  memory_set('\b', PROMPT_LENGTH, (char *)bs);
+  memory_set(' ', PROMPT_LENGTH, (char *)ws);
+
+  WRITE_D("Welcome to FreywarOS v" VERSION "!\n\n");
+
+  print_prompt();
+
+  while (1) {
+    char c;
+    if (read(0, 1, &c)) {
+      on_char_received(c);
+    }
+  }
+
+  return 0;
+}