feat: add support for shell builtins to command completion

kernel/src/Api/BuildNo.hpp

@@ -12,4 +12,4 @@
 
 #pragma once
 
-#define MONTAUK_BUILD_NUMBER 79
+#define MONTAUK_BUILD_NUMBER 82

programs/src/shell/main.cpp

@@ -436,6 +436,8 @@ extern "C" void _start() {
         if (ev.scancode == SC_TAB) {
             line[pos] = '\0';
 
+            if (pos == 0) continue;
+
             char* table[128] = { };
             int n = get_completions(line, table, 128);
 

programs/src/shell/shell.h

@@ -130,3 +130,18 @@ int exec_external(const char* cmd, const char* args);
 // ---- Tab completion (tabcompletion.cpp) ----
 
 int get_completions(char* string, char** array, int arrayMax);
+
+// ---- Shell builtins ----
+
+constexpr const char* shell_builtins[] = {
+    "help",
+    "ls",
+    "cd",
+    "pwd",
+    "echo",
+    "set",
+    "unset",
+    "true",
+    "false",
+    "exit"
+};

programs/src/shell/tabcompletion.cpp

@@ -6,6 +6,7 @@
 
 #include <montauk/string.h>
 #include <montauk/syscall.h>
+#include "shell.h"
 
 #define RD_MAX 128
 
@@ -58,6 +59,7 @@ int get_completions(		// returns no. of results
 		int	arrayMax
 	) {
 	
+	// --- System commands (0:/os/*.elf) ----
 	const char* names[RD_MAX] 	= { };
 
 	int n = montauk::readdir("0:/os", names, RD_MAX);
@@ -89,5 +91,19 @@ int get_completions(		// returns no. of results
 		} 
 	}
 
+	// ---- Shell builtins ----
+	
+	size_t builtins_count = sizeof(shell_builtins) / sizeof(const char*);
+
+	for (size_t i = 0; i < builtins_count; i++) {
+		if (montauk::starts_with(shell_builtins[i], (const char*)string)) {
+			if (r > arrayMax)
+				break;
+			
+			array[r] = (char *)shell_builtins[i];
+			r++;
+		}
+	}
+
 	return r;
 }