[PATCH 1/2] kconfig: remove unneeded buffer allocation in zconf_initscan()

[PATCH 1/2] kconfig: remove unneeded buffer allocation in zconf_initscan()

[Masahiro Yamada]

In Kconfig, there is a stack to save the lexer state for each inclusion
level.

Currently, it operates as an empty stack, with the 'current_buf' always
pointing to an empty buffer. There is no need to preallocate the buffer.
Change it to a full stack.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
---

 scripts/kconfig/lexer.l | 29 +++++++++++++----------------
 1 file changed, 13 insertions(+), 16 deletions(-)

diff --git a/scripts/kconfig/lexer.l b/scripts/kconfig/lexer.l
index cc386e443683..d75423ec4eae 100644
--- a/scripts/kconfig/lexer.l
+++ b/scripts/kconfig/lexer.l
@@ -391,9 +391,6 @@ void zconf_initscan(const char *name)
 		exit(1);
 	}
 
-	current_buf = xmalloc(sizeof(*current_buf));
-	memset(current_buf, 0, sizeof(*current_buf));
-
 	current_file = file_lookup(name);
 	yylineno = 1;
 }
@@ -403,9 +400,10 @@ void zconf_nextfile(const char *name)
 	struct file *iter;
 	struct file *file = file_lookup(name);
 	struct buffer *buf = xmalloc(sizeof(*buf));
-	memset(buf, 0, sizeof(*buf));
 
-	current_buf->state = YY_CURRENT_BUFFER;
+	buf->state = YY_CURRENT_BUFFER;
+	buf->parent = current_buf;
+	current_buf = buf;
 	yyin = zconf_fopen(file->name);
 	if (!yyin) {
 		fprintf(stderr, "%s:%d: can't open file \"%s\"\n",
@@ -413,8 +411,6 @@ void zconf_nextfile(const char *name)
 		exit(1);
 	}
 	yy_switch_to_buffer(yy_create_buffer(yyin, YY_BUF_SIZE));
-	buf->parent = current_buf;
-	current_buf = buf;
 
 	current_file->lineno = yylineno;
 	file->parent = current_file;
@@ -441,20 +437,21 @@ void zconf_nextfile(const char *name)
 
 static void zconf_endfile(void)
 {
-	struct buffer *parent;
+	struct buffer *tmp;
 
 	current_file = current_file->parent;
 	if (current_file)
 		yylineno = current_file->lineno;
 
-	parent = current_buf->parent;
-	if (parent) {
-		fclose(yyin);
-		yy_delete_buffer(YY_CURRENT_BUFFER);
-		yy_switch_to_buffer(parent->state);
-	}
-	free(current_buf);
-	current_buf = parent;
+	if (!current_buf)
+		return;
+
+	fclose(yyin);
+	yy_delete_buffer(YY_CURRENT_BUFFER);
+	yy_switch_to_buffer(current_buf->state);
+	tmp = current_buf;
+	current_buf = current_buf->parent;
+	free(tmp);
 }
 
 int zconf_lineno(void)
-- 
2.40.1

[PATCH 2/2] kconfig: fix line number in recursive inclusion detection

[Masahiro Yamada]

The error message shows a wrong line number if the 'source' directive
is wrapped to the following line.

[Test Code]

  source \
  "Kconfig"

This results in the following error message:

  Recursive inclusion detected.
  Inclusion path:
    current file : Kconfig
    included from: Kconfig:2

The correct message should be as follows:

  Recursive inclusion detected.
  Inclusion path:
    current file : Kconfig
    included from: Kconfig:1

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
---

 scripts/kconfig/lexer.l | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/scripts/kconfig/lexer.l b/scripts/kconfig/lexer.l
index d75423ec4eae..b3aeb29695d7 100644
--- a/scripts/kconfig/lexer.l
+++ b/scripts/kconfig/lexer.l
@@ -33,6 +33,7 @@ static int text_size, text_asize;
 struct buffer {
 	struct buffer *parent;
 	YY_BUFFER_STATE state;
+	int lineno;
 };
 
 static struct buffer *current_buf;
@@ -402,6 +403,7 @@ void zconf_nextfile(const char *name)
 	struct buffer *buf = xmalloc(sizeof(*buf));
 
 	buf->state = YY_CURRENT_BUFFER;
+	buf->lineno = yylineno;
 	buf->parent = current_buf;
 	current_buf = buf;
 	yyin = zconf_fopen(file->name);
@@ -412,7 +414,7 @@ void zconf_nextfile(const char *name)
 	}
 	yy_switch_to_buffer(yy_create_buffer(yyin, YY_BUF_SIZE));
 
-	current_file->lineno = yylineno;
+	current_file->lineno = zconf_lineno();
 	file->parent = current_file;
 
 	for (iter = current_file; iter; iter = iter->parent) {
@@ -425,7 +427,7 @@ void zconf_nextfile(const char *name)
 			do {
 				iter = iter->parent;
 				fprintf(stderr, "  included from: %s:%d\n",
-					iter->name, iter->lineno - 1);
+					iter->name, iter->lineno);
 			} while (strcmp(iter->name, file->name));
 			exit(1);
 		}
@@ -440,8 +442,6 @@ static void zconf_endfile(void)
 	struct buffer *tmp;
 
 	current_file = current_file->parent;
-	if (current_file)
-		yylineno = current_file->lineno;
 
 	if (!current_buf)
 		return;
@@ -449,6 +449,7 @@ static void zconf_endfile(void)
 	fclose(yyin);
 	yy_delete_buffer(YY_CURRENT_BUFFER);
 	yy_switch_to_buffer(current_buf->state);
+	yylineno = current_buf->lineno;
 	tmp = current_buf;
 	current_buf = current_buf->parent;
 	free(tmp);
-- 
2.40.1