parse: lex: improve scanning of more complex redirection expressions

bshell/parse/lex/command.c

@@ -1,3 +1,4 @@
+#include "../token.h"
 #include "lex-internal.h"
 
 static bool char_can_continue_word(struct lex_ctx *ctx, fx_wchar c)
@@ -34,6 +35,8 @@ static enum bshell_status command_symbol(struct lex_ctx *ctx)
 
 	struct lex_token *tok = NULL;
 	switch (sym->id) {
+	case SYM_DQUOTE:
+		return BSHELL_SUCCESS;
 	case SYM_SQUOTE:
 		status = read_literal_string(ctx, &tok);
 		if (status != BSHELL_SUCCESS) {
@@ -85,6 +88,39 @@ static enum bshell_status command_symbol(struct lex_ctx *ctx)
 	return BSHELL_SUCCESS;
 }
 
+static bool string_is_redirection(const char *s)
+{
+	if (!*s) {
+		return false;
+	}
+
+	if (!strcmp(s, ">") || !strcmp(s, ">>")) {
+		return true;
+	}
+
+	long nr_angles = 0;
+	for (size_t i = 0; s[i];) {
+		fx_wchar c = fx_wchar_utf8_codepoint_decode(s);
+		if (fx_wchar_is_number(c)) {
+			if (nr_angles) {
+				return false;
+			}
+		} else if (c == '>') {
+			nr_angles++;
+
+			if (nr_angles > 2) {
+				return false;
+			}
+		} else {
+			return false;
+		}
+
+		s += fx_wchar_utf8_codepoint_stride(s);
+	}
+
+	return true;
+}
+
 static enum bshell_status command_word(struct lex_ctx *ctx)
 {
 	struct lex_token *word = NULL;
@@ -97,6 +133,7 @@ static enum bshell_status command_word(struct lex_ctx *ctx)
 	bool continue_word = false;
 
 	fx_wchar c = peek_char(ctx);
+	const char *s = word->tok_str;
 	if (char_can_begin_symbol_in_state(ctx, c, LEX_STATE_WORD)) {
 		continue_word = true;
 	}
@@ -105,6 +142,10 @@ static enum bshell_status command_word(struct lex_ctx *ctx)
 		continue_word = false;
 	}
 
+	if (string_is_redirection(s)) {
+		continue_word = false;
+	}
+
 	if (continue_word) {
 		lex_state_push(ctx, LEX_STATE_WORD, 0);
 	}
@@ -171,6 +212,8 @@ static const unsigned int symbols[] = {
 	SYM_PIPE,
 	SYM_SEMICOLON,
 	SYM_RIGHT_PAREN,
+	SYM_LEFT_PAREN,
+	SYM_LEFT_BRACE,
 	SYM_RIGHT_BRACE,
 	SYM_NONE,
 };