feat: redirection rules

src/parser/grammar_advanced.c

@@ -0,0 +1,28 @@
+#include "grammar_advanced.h"
+
+#include <stdio.h>
+
+#include "grammar_basic.h"
+
+struct ast *parse_redirection(struct lexer_context *ctx)
+{
+    struct token *token = PEEK_TOKEN();
+    if (token->type == TOKEN_IONUMBER)
+    {
+        // TODO
+        POP_TOKEN();
+        token = PEEK_TOKEN();
+    }
+
+    if (token->type != TOKEN_REDIRECTION)
+    {
+        puts("Syntax error: expected a redirection token but got something "
+             "else");
+        return NULL;
+    }
+}
+
+struct ast *parse_prefix(struct lexer_context *ctx)
+{
+    return parse_redirection(ctx);
+}

src/parser/grammar_advanced.h

@@ -1,4 +1,27 @@
 #ifndef GRAMMAR_ADVANCED_H
 #define GRAMMAR_ADVANCED_H
 
+#include "grammar.h"
+
+// === Functions
+
+/*
+ * @brief parses a redirection rule
+ *
+ * @code redirection = [IONUMBER] ( '>' | '<' | '>>' | '>&' | '<&' | '>|' | '<>' ) WORD ;
+ *
+ * @first TOKEN_IONUMBER, TOKEN_REDIRECTION
+ */
+struct ast *parse_redirection(struct lexer_context *ctx);
+
+/*
+ * @brief parses a prefix rule
+ *
+ * @code prefix = redirection ;
+ *
+ * @first first(redirection)
+ */
+struct ast *parse_prefix(struct lexer_context *ctx);
+
+
 #endif /* ! GRAMMAR_ADVANCED_H */

src/parser/grammar_basic.c

@@ -3,9 +3,9 @@
 #include <stdio.h>
 #include <string.h>
 
-#include "../lexer/lexer.h"
 #include "../utils/lists/lists.h"
 #include "grammar.h"
+#include "grammar_advanced.h"
 
 // === Static functions
 
@@ -124,46 +124,86 @@ struct ast *parse_command(struct lexer_context *ctx)
 struct ast *parse_simple_command(struct lexer_context *ctx)
 {
     struct list *command_elements = NULL;
-    struct token *token = PEEK_TOKEN();
+
+    // WORD
+    struct token *token = POP_TOKEN();
     if (token->type != TOKEN_WORD)
     {
         puts("Expected a command but got a different token type");
         return NULL;
     }
+    char *command = strdup(token->data);
+    command_elements = list_append(command_elements, command);
 
+    token = PEEK_TOKEN();
+
+    // Eventual elements
     while (token->type == TOKEN_WORD)
     {
-        token = pop_token(ctx);
+        // Get element
-        if (token == NULL)
+        struct ast *element = parse_element(ctx);
+        if (element == NULL)
         {
-            // TODO free
+            list_deep_destroy(command_elements);
             return NULL;
         }
-        char *word = strdup(token->data);
-        if (word == NULL)
-        {
-            // TODO free
-            puts("Internal error: Couldn't copy token content (is memory full "
-                 "?)");
-            return NULL;
-        }
-        command_elements = list_append(command_elements, word);
-        token = peek_token(ctx);
-        if (token == NULL)
-        {
-            // TODO free
-            return NULL;
-        }
-    }
 
+        // Get element type
+        if (ast_is_word(element))
+        {
+            struct ast_word *element_word = ast_get_word(element);
+            command_elements =
+                list_append(command_elements, element_word->word);
+        }
+        else if (ast_is_redir(element))
+        {
+            // TODO
+            puts("NOT IMPLEMENTED");
+            return NULL;
+        }
+        else
+        {
+            puts("Internal error: unexpected return value from parse_element "
+                 "in parse_simple_command");
+            list_deep_destroy(command_elements);
+            return NULL;
+        }
+
+        // Forward
+        POP_TOKEN();
+        token = PEEK_TOKEN();
+    }
+
+    // Result
     struct ast *result = ast_create_command(command_elements);
     if (result == NULL)
     {
-        // TODO free
+        list_deep_destroy(command_elements);
+        return NULL;
     }
     return result;
 }
 
+struct ast *parse_element(struct lexer_context *ctx)
+{
+    struct token *token = PEEK_TOKEN();
+    if (token->type == TOKEN_WORD)
+    {
+        // TODO
+        puts("NOT IMPLEMENTED");
+        return NULL;
+    }
+    else if (token->type == TOKEN_IONUMBER || token->type == TOKEN_REDIRECTION)
+    {
+        return parse_redirection(ctx);
+    }
+    else
+    {
+        puts("Syntax error: unexpected token at parse_element");
+        return NULL;
+    }
+}
+
 struct ast *parse_shell_command(struct lexer_context *ctx)
 {
     return parse_if_rule(ctx);

src/parser/grammar_basic.h

@@ -6,7 +6,8 @@
 
 // === Functions
 
-/* @brief: parses a list of [and_or] rules separated by semicolons and that
+/*
+ * @brief parses a list of [and_or] rules separated by semicolons and that
  *         ends by a newline
  *
  * @code list = and_or { ';' and_or } [ ';' ] ;
@@ -15,7 +16,8 @@
  */
 struct ast *parse_list(struct lexer_context *ctx);
 
-/* @brief Only parses a pipeline rule for the moment
+/*
+ * @brief Only parses a pipeline rule for the moment
  *
  * @code and_or = pipeline { ( '&&' | '||' ) {'\n'} pipeline } ;
  *
@@ -23,7 +25,8 @@ struct ast *parse_list(struct lexer_context *ctx);
  */
 struct ast *parse_and_or(struct lexer_context *ctx);
 
-/* @brief Only parses a command rule for the moment
+/*
+ * @brief Only parses a command rule for the moment
  *
  * @code pipeline = command ;
  *
@@ -31,7 +34,8 @@ struct ast *parse_and_or(struct lexer_context *ctx);
  */
 struct ast *parse_pipeline(struct lexer_context *ctx);
 
-/* @brief Parses a simple command rule or a shell command rule depending on
+/*
+ * @brief Parses a simple command rule or a shell command rule depending on
  *        the first token.
  * @note
  *        TOKEN_WORD => simple_command
@@ -44,7 +48,8 @@ struct ast *parse_pipeline(struct lexer_context *ctx);
  */
 struct ast *parse_command(struct lexer_context *ctx);
 
-/* @brief Parses a simple list of words (command and arguments)
+/*
+ * @brief Parses a simple list of words (command and arguments)
  *        ending by a separator
  *
  * @code simple_command = WORD { element } ;
@@ -53,7 +58,19 @@ struct ast *parse_command(struct lexer_context *ctx);
  */
 struct ast *parse_simple_command(struct lexer_context *ctx);
 
-/* @brief Only parses if rules for the moment
+/*
+ * @brief Parses an element rule
+ *
+ * @code element = WORD
+ *               | redirection
+ *               ;
+ *
+ * @first WORD, first(redirection)
+ */
+struct ast *parse_element(struct lexer_context *ctx);
+
+/*
+ * @brief Only parses if rules for the moment
  *
  * @code shell_command = if_rule ;
  *
@@ -61,7 +78,8 @@ struct ast *parse_simple_command(struct lexer_context *ctx);
  */
 struct ast *parse_shell_command(struct lexer_context *ctx);
 
-/* @brief Parses a if rule (condition, then-clause, elif-clause, else-clause)
+/*
+ * @brief Parses a if rule (condition, then-clause, elif-clause, else-clause)
  *
  * @code if_rule = 'if' compound_list 'then' compound_list [else_clause] 'fi' ;
  *
@@ -69,7 +87,8 @@ struct ast *parse_shell_command(struct lexer_context *ctx);
  */
 struct ast *parse_if_rule(struct lexer_context *ctx);
 
-/* @brief parses commands inside if/else clauses and returns the corresponding
+/*
+ * @brief parses commands inside if/else clauses and returns the corresponding
  * AST list
  *
  * @code compound_list = {'\n'} and_or { ( ';' | '\n' ) {'\n'} and_or } [';']
@@ -79,7 +98,8 @@ struct ast *parse_if_rule(struct lexer_context *ctx);
  */
 struct ast *parse_compound_list(struct lexer_context *ctx);
 
-/* @brief
+/*
+ * @brief
  *
  * @code else_clause = 'else' compound_list
  *                   | 'elif' compound_list 'then' compound_list [else_clause]

src/utils/ast/ast.h

@@ -9,6 +9,7 @@
 #include "ast_list.h"
 #include "ast_redir.h"
 #include "ast_void.h"
+#include "ast_word.h"
 
 /**
  * Prints the Graphviz DOT representation of the given AST to stdout.

src/utils/ast/ast_base.h

@@ -11,7 +11,8 @@ enum ast_type
     AST_AND_OR,
     AST_REDIR,
     AST_VOID,
-    AST_CMD
+    AST_CMD,
+    AST_WORD
 };
 
 struct ast

src/utils/ast/ast_word.c

@@ -0,0 +1,45 @@
+#include "ast_word.h"
+
+#include <stdbool.h>
+#include <stdlib.h>
+#include <string.h>
+
+struct ast *ast_create_word(char *word)
+{
+    struct ast_word *ast_node = malloc(sizeof(struct ast_word));
+    if (ast_node == NULL)
+        return NULL;
+
+    ast_node->type = AST_WORD;
+    ast_node->word = strdup(word);
+    struct ast *res = ast_create(AST_WORD, ast_node);
+    if (res == NULL)
+    {
+        free(ast_node);
+        return NULL;
+    }
+
+    return res;
+}
+
+struct ast_word *ast_get_word(struct ast *node)
+{
+    if (node == NULL || node->type != AST_WORD)
+        return NULL;
+
+    return node->data;
+}
+
+bool ast_is_word(struct ast *node)
+{
+    return node && node->type == AST_WORD;
+}
+
+void ast_free_word(struct ast_word *ast_node)
+{
+    if (ast_node == NULL)
+        return;
+
+    free(ast_node->word);
+    free(ast_node);
+}

src/utils/ast/ast_word.h

@@ -0,0 +1,35 @@
+#ifndef AST_WORD_H
+#define AST_WORD_H
+
+#include <stdbool.h>
+
+#include "ast_base.h"
+
+struct ast_word
+{
+    enum ast_type type;
+    char *word;
+};
+
+/**
+ * Checks if the given AST node is a command.
+ */
+bool ast_is_word(struct ast *node);
+
+/**
+ * Retrieves the command data from the given AST node.
+ * Assumes that the node is of type AST_CMD.
+ */
+struct ast_word *ast_get_word(struct ast *node);
+
+/**
+ * Creates a new AST node representing a command.
+ */
+struct ast *ast_create_word(char* word);
+
+/*
+ * @brief: frees the given ast_command and sets the pointer to NULL.
+ */
+void ast_free_word(struct ast_word *ast_node);
+
+#endif /* ! AST_WORD_H */