Split CE code into multiple files

ce/parser.h

@@ -0,0 +1,92 @@
+#ifndef _PARSER_H
+#define _PARSER_H
+
+#include <list.h>
+
+#define TOKEN_MAX    64
+#define CMD_ARGS_MAX 64
+
+#define TOKEN_CLASS_OPAREN    0
+#define TOKEN_CLASS_CPAREN    1
+#define TOKEN_CLASS_WORD      2
+#define TOKEN_CLASS_SEMICOLON 3
+#define TOKEN_CLASS_REDIR     4
+
+struct token {
+  struct list_node_link tokens_link;
+  char buffer[TOKEN_MAX];
+  int class;
+};
+
+#define PREC_NONE   0
+#define PREC_LOWEST 1
+#define PREC_SEQ    2
+#define PREC_REDIR  3
+
+#define AST_NODE_CLASS_CMD      0
+#define AST_NODE_CLASS_SUBSHELL 1
+#define AST_NODE_CLASS_SEQ      2
+#define AST_NODE_CLASS_REDIR    3
+
+struct ast_node;
+
+struct ast_cmd {
+  char* name;
+  char* args[CMD_ARGS_MAX];
+  int arg_count;
+};
+
+struct ast_subshell {
+  struct ast_node* inner;
+};
+
+struct ast_seq {
+  struct ast_node* left;
+  struct ast_node* right;
+};
+
+struct ast_redir {
+  struct ast_node* source;
+  char* file_path;
+};
+
+struct ast_node {
+  int class;
+  union {
+    struct ast_cmd cmd;
+    struct ast_subshell subshell;
+    struct ast_seq seq;
+    struct ast_redir redir;
+  } u;
+};
+
+struct parser;
+
+typedef struct ast_node* (*nud_func_t) (struct parser* parser, struct token* token);
+typedef struct ast_node* (*led_func_t) (struct parser* parser, struct token* token,
+                                        struct ast_node* left);
+
+struct parse_rule {
+  nud_func_t nud;
+  led_func_t led;
+  int precedence;
+};
+
+struct parser {
+  struct token* current;
+  struct token* next;
+};
+
+struct ast_node* word_nud (struct parser* parser, struct token* token);
+
+struct ast_node* oparen_nud (struct parser* parser, struct token* token);
+
+struct ast_node* semicolon_led (struct parser* parser, struct token* token, struct ast_node* left);
+
+struct ast_node* redir_led (struct parser* parser, struct token* token, struct ast_node* left);
+
+void tokenize (struct list_node_link** tokens, const char* text);
+
+void parse_and_execute (struct list_node_link* tokens);
+
+#endif // _PARSER_H