update readme, we've finalized on being bourne shell compatible

README.md

@@ -1,5 +1,5 @@
 # msh
 
-msh is a WIP shell with the goal of being portable to older operating systems, namely classic Windows and classic Mac OS. While the former already has a shell, the aim for both is to provide something closer to what linux shells provide (with exceptions ofc).
+msh is a WIP shell with the goal of being portable to older operating systems, namely classic Windows and classic Mac OS. While the former already has a shell, the aim for both is to provide something equivalant Unix's bourne shell (as well as some from bash/zsh).
 
 It's written without the C standard library. Ports instead must implement `src/system/system.h` accordingly. It's also written in C89/C99 (mostly the former as it's needed for some compilers, but if C99 is supported by a platform's backend then it'll probably be used).

src/exec.c

@@ -1,3 +1,32 @@
+/*
+   Copyright 2026 msh team
+
+   Redistribution and use in source and binary forms, with or without
+   modification, are permitted provided that the following conditions are met:
+
+   1. Redistributions of source code must retain the above copyright notice,
+   this list of conditions and the following disclaimer.
+
+   2. Redistributions in binary form must reproduce the above copyright notice,
+   this list of conditions and the following disclaimer in the documentation
+   and/or other materials provided with the distribution.
+
+   3. Neither the name of the copyright holder nor the names of its
+   contributors may be used to endorse or promote products derived from this
+   software without specific prior written permission.
+
+   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS “AS IS”
+   AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+   IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+   ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+   LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+   CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+   SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+   INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+   CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+   ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+   POSSIBILITY OF SUCH DAMAGE.
+*/
 #include "builtins/builtins.h"
 #include "lexer/lexer.h"
 #include "system/system.h"

src/lexer/lexer.c

@@ -64,6 +64,35 @@ void msh_lexer_push_item(msh_lexer *lexer, msh_lexer_item_type type, char *buf,
   lexer->item_list_cur = lexer->item_list_cur->next;
 };
 
+/* function for either pushing a regular word or pushing a keyword to the
+ * buffer. */
+static void word_push(msh_lexer *lexer, char *cur_word_buf, int *n) {
+  int hash = 0;
+  cur_word_buf[*n] = '\0';
+  hash = str_hash(cur_word_buf);
+  switch (hash) {
+  case MSH_LEXER_ITEM_TYPE_WORD_KEYWORD_IF:
+  case MSH_LEXER_ITEM_TYPE_WORD_KEYWORD_THEN:
+  case MSH_LEXER_ITEM_TYPE_WORD_KEYWORD_ELSE:
+  case MSH_LEXER_ITEM_TYPE_WORD_KEYWORD_ELIF:
+  case MSH_LEXER_ITEM_TYPE_WORD_KEYWORD_FI:
+  case MSH_LEXER_ITEM_TYPE_WORD_KEYWORD_CASE:
+  case MSH_LEXER_ITEM_TYPE_WORD_KEYWORD_IN:
+  case MSH_LEXER_ITEM_TYPE_WORD_KEYWORD_ESAC:
+  case MSH_LEXER_ITEM_TYPE_WORD_KEYWORD_FOR:
+  case MSH_LEXER_ITEM_TYPE_WORD_KEYWORD_WHILE:
+  case MSH_LEXER_ITEM_TYPE_WORD_KEYWORD_UNTIL:
+  case MSH_LEXER_ITEM_TYPE_WORD_KEYWORD_DO:
+  case MSH_LEXER_ITEM_TYPE_WORD_KEYWORD_DONE:
+    msh_lexer_push_item(lexer, hash, cur_word_buf, *n);
+    break;
+  default:
+    msh_lexer_push_item(lexer, MSH_LEXER_ITEM_TYPE_WORD, cur_word_buf, *n);
+    break;
+  }
+  *n += 1;
+};
+
 void msh_lexer_parse(msh_lexer *lexer, char *buf, SIZE_TYPE sz) {
   int i = 0, n = 0, j = 0;
   char cur_word_buf[1024];
@@ -94,8 +123,7 @@ void msh_lexer_parse(msh_lexer *lexer, char *buf, SIZE_TYPE sz) {
     char do_clear = 0;
     switch (buf[i]) {
     case '#':
-      cur_word_buf[n++] = '\0';
-      msh_lexer_push_item(lexer, MSH_LEXER_ITEM_TYPE_WORD, cur_word_buf, n);
+      word_push(lexer, cur_word_buf, &n);
       goto lexer_cancel;
     case '\\':
       escaping = 1;
@@ -125,8 +153,7 @@ void msh_lexer_parse(msh_lexer *lexer, char *buf, SIZE_TYPE sz) {
       /* fallthrough */
     case '\n':
     case '\0':
-      cur_word_buf[n++] = '\0';
-      msh_lexer_push_item(lexer, MSH_LEXER_ITEM_TYPE_WORD, cur_word_buf, n);
+      word_push(lexer, cur_word_buf, &n);
       do_clear = 1;
       break;
     default:

src/lexer/lexer.h

@@ -41,6 +41,21 @@ typedef enum msh_lexer_item_type_t {
   MSH_LEXER_ITEM_TYPE_OP_PIPE,      /* | */
   MSH_LEXER_ITEM_TYPE_OP_CONTROL,   /* & */
   MSH_LEXER_ITEM_TYPE_OP_SEMICOLON, /* ; */
+
+  /* the keyword types have values corresponding to their string hash */
+  MSH_LEXER_ITEM_TYPE_WORD_KEYWORD_IF = 177678,        /* if */
+  MSH_LEXER_ITEM_TYPE_WORD_KEYWORD_THEN = 193506854,   /* then */
+  MSH_LEXER_ITEM_TYPE_WORD_KEYWORD_ELSE = 193490665,   /* else */
+  MSH_LEXER_ITEM_TYPE_WORD_KEYWORD_ELIF = 193490655,   /* elif */
+  MSH_LEXER_ITEM_TYPE_WORD_KEYWORD_FI = 177675655,     /* fi */
+  MSH_LEXER_ITEM_TYPE_WORD_KEYWORD_CASE = 193488124,   /* case */
+  MSH_LEXER_ITEM_TYPE_WORD_KEYWORD_IN = 177678124,     /* in */
+  MSH_LEXER_ITEM_TYPE_WORD_KEYWORD_ESAC = 193490878,   /* esac */
+  MSH_LEXER_ITEM_TYPE_WORD_KEYWORD_FOR = 586338678,    /* for */
+  MSH_LEXER_ITEM_TYPE_WORD_KEYWORD_WHILE = 2090866937, /* while */
+  MSH_LEXER_ITEM_TYPE_WORD_KEYWORD_UNTIL = 2090801957, /* until */
+  MSH_LEXER_ITEM_TYPE_WORD_KEYWORD_DO = 1776731957,    /* do */
+  MSH_LEXER_ITEM_TYPE_WORD_KEYWORD_DONE = 1934896707,  /* done */
 } msh_lexer_item_type;
 
 typedef struct msh_lexer_item_t {

src/main.c

@@ -29,6 +29,7 @@
 */
 #include "lexer/lexer.h"
 #include "system/system.h"
+#include "util/util.h"
 
 static struct {
   msh_lexer lexer;