mds-kbdc: split out and dedup include stack

Signed-off-by: Mattias Andrée <maandree@operamail.com>

5 files changed, 314 insertions, 205 deletions

diff --git a/Makefile b/Makefile
index 35e9591..27d92e8 100644
--- a/Makefile
+++ b/Makefile
@@ -32,7 +32,8 @@ OBJ_mds-registry_ = mds-registry util globals reexec registry signals   \
 
 OBJ_mds-kbdc_     = mds-kbdc globals raw-data functions string tree     \
                     make-tree parse-error simplify-tree parsed          \
-                    process-includes validate-tree eliminate-dead-code
+                    process-includes validate-tree eliminate-dead-code  \
+                    include-stack
 
 OBJ_mds-server    = $(foreach O,$(OBJ_mds-server_),obj/mds-server/$(O).o)
 OBJ_mds-registry  = $(foreach O,$(OBJ_mds-registry_),obj/mds-registry/$(O).o)
diff --git a/src/mds-kbdc/eliminate-dead-code.c b/src/mds-kbdc/eliminate-dead-code.c
index cedf576..0881b20 100644
--- a/src/mds-kbdc/eliminate-dead-code.c
+++ b/src/mds-kbdc/eliminate-dead-code.c
@@ -17,6 +17,8 @@
  */
 #include "eliminate-dead-code.h"
 
+#include "include-stack.h"
+
 #include <stdlib.h>
 #include <errno.h>
 
@@ -28,26 +30,6 @@
 #define C(TYPE)  MDS_KBDC_TREE_TYPE_##TYPE
 
 /**
- * Add an error to the error list
- * 
- * @param  NODE:const mds_kbdc_tree_t*    The node the triggered the error
- * @param  SEVERITY:identifier            * in `MDS_KBDC_PARSE_ERROR_*` to indicate severity
- * @param  ...:const char*, ...           Error description format string and arguments
- * @scope  error:mds_kbdc_parse_error_t*  Variable where the new error will be stored
- */
-#define NEW_ERROR_WITHOUT_INCLUDES(NODE, SEVERITY, ...)			\
-  NEW_ERROR_(result, SEVERITY, 1, (NODE)->loc_line,			\
-	     (NODE)->loc_start, (NODE)->loc_end, 1, __VA_ARGS__)
-
-/**
- * Add “included from here”-notes
- * 
- * @param  PTR:size_t  The number of “included from here”-notes
- */
-#define DUMP_INCLUDE_STACK(PTR)		\
-  fail_if (dump_include_stack(PTR))
-
-/**
  * Add an error with “included from here”-notes to the error list
  * 
  * @param  NODE:const mds_kbdc_tree_t*    The node the triggered the error
@@ -57,12 +39,7 @@
  * @scope  error:mds_kbdc_parse_error_t*  Variable where the new error will be stored
  */
 #define NEW_ERROR(NODE, PTR, SEVERITY, ...)			\
-  do								\
-    {								\
-      NEW_ERROR_WITHOUT_INCLUDES(NODE, SEVERITY, __VA_ARGS__);	\
-      DUMP_INCLUDE_STACK(PTR);					\
-    }								\
-  while (0)
+  NEW_ERROR_WITH_INCLUDES(NODE, PTR, SEVERITY, __VA_ARGS__)
 
 
 
@@ -77,31 +54,6 @@ static mds_kbdc_parse_error_t* error;
 static mds_kbdc_parsed_t* restrict result;
 
 /**
- * The original value of `result->pathname`
- */
-static char* original_pathname;
-
-/**
- * The original value of `result->source_code`
- */
-static mds_kbdc_source_code_t* original_source_code;
-
-/**
- * Stack of visited include-statements
- */
-static mds_kbdc_tree_include_t** restrict includes = NULL;
-
-/**
- * The number elements allocated for `includes`
- */
-static size_t includes_size = 0;
-
-/**
- * The number elements stored in `includes`
- */
-static size_t includes_ptr = 0;
-
-/**
  * 2: Eliminating because of a return-statement
  * 1: Eliminating because of a break- or continue-statement
  * 0: Not eliminating
@@ -121,32 +73,6 @@ static int eliminate_subtree(mds_kbdc_tree_t* restrict tree);
 
 
 /**
- * Add “included from here”-notes
- * 
- * @param   ptr  The number of “included from here”-notes
- * @return       Zero on success, -1 on error
- */
-static int dump_include_stack(size_t ptr)
-{
-  char* old_pathname = result->pathname;
-  mds_kbdc_source_code_t* old_source_code = result->source_code;
-  while (ptr--)
-    {
-      result->pathname = ptr ? includes[ptr - 1]->filename : original_pathname;
-      result->source_code = ptr ? includes[ptr - 1]->source_code : original_source_code;
-      NEW_ERROR_WITHOUT_INCLUDES(includes[ptr], NOTE, "included from here");
-    }
-  result->pathname = old_pathname;
-  result->source_code = old_source_code;
-  return 0;
- pfail:
-  result->pathname = old_pathname;
-  result->source_code = old_source_code;
-  return -1;
-} 
-
-  
-/**
  * Eliminate dead code in an include-statement
  * 
  * @param   tree  The tree to reduce
@@ -154,20 +80,13 @@ static int dump_include_stack(size_t ptr)
  */
 static int eliminate_include(mds_kbdc_tree_include_t* restrict tree)
 {
-  mds_kbdc_tree_include_t** old;
-  char* pathname = result->pathname;
-  mds_kbdc_source_code_t* source_code = result->source_code;
-  int r, saved_errno;
-  if (includes_ptr == includes_size)
-    if (xxrealloc(old, includes, includes_size += 4, mds_kbdc_tree_include_t*))
-      return saved_errno = errno, free(old), errno = saved_errno, -1;
-  includes[includes_ptr++] = tree;
-  result->pathname = tree->filename;
-  result->source_code = tree->source_code;
+  void* data;
+  int r;
+  if (mds_kbdc_include_stack_push(tree, &data))
+    return -1;
   r = eliminate_subtree(tree->inner);
-  result->pathname = pathname;
-  result->source_code = source_code;
-  return includes_ptr--, r;
+  mds_kbdc_include_stack_pop(data);
+  return r;
 }
 
 
@@ -252,23 +171,14 @@ static int eliminate_subtree(mds_kbdc_tree_t* restrict tree)
  */
 int eliminate_dead_code(mds_kbdc_parsed_t* restrict result_)
 {
-  int r, saved_errno;
-  result = result_;
-  original_pathname = result_->pathname;
-  original_source_code = result_->source_code;
+  int r;
+  mds_kbdc_include_stack_begin(result = result_);
   r = eliminate_subtree(result_->tree);
-  saved_errno = errno;
-  result_->pathname = original_pathname;
-  result_->source_code = original_source_code;
-  free(includes), includes = NULL;
-  includes_size = includes_ptr = 0;
-  return errno = saved_errno, r;
+  return mds_kbdc_include_stack_end(), r;
 }
 
 
 
 #undef NEW_ERROR
-#undef DUMP_INCLUDE_STACK
-#undef NEW_ERROR_WITHOUT_INCLUDES
 #undef C
 
diff --git a/src/mds-kbdc/include-stack.c b/src/mds-kbdc/include-stack.c
new file mode 100644
index 0000000..e3aff48
--- /dev/null
+++ b/src/mds-kbdc/include-stack.c
@@ -0,0 +1,170 @@
+/**
+ * mds — A micro-display server
+ * Copyright © 2014  Mattias Andrée (maandree@member.fsf.org)
+ * 
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#include "include-stack.h"
+
+#include <alloca.h>
+#include <stdlib.h>
+#include <errno.h>
+
+
+
+/**
+ * Variable whether the latest created error is stored
+ */
+static mds_kbdc_parse_error_t* error;
+
+/**
+ * The `result` parameter of root procedure that requires the include stack
+ */
+static mds_kbdc_parsed_t* restrict result;
+
+/**
+ * The original value of `result->pathname`
+ */
+static char* original_pathname;
+
+/**
+ * The original value of `result->source_code`
+ */
+static mds_kbdc_source_code_t* original_source_code;
+
+/**
+ * Stack of visited include-statements
+ */
+static mds_kbdc_tree_include_t** restrict includes = NULL;
+
+/**
+ * The number elements allocated for `includes`
+ */
+static size_t includes_size = 0;
+
+/**
+ * The number elements stored in `includes`
+ */
+size_t includes_ptr = 0;
+
+
+
+/**
+ * Add “included from here”-notes
+ * 
+ * @param   ptr  The number of “included from here”-notes
+ * @return       Zero on success, -1 on error
+ */
+int mds_kbdc_include_stack_dump(size_t ptr)
+{
+  char* old_pathname = result->pathname;
+  mds_kbdc_source_code_t* old_source_code = result->source_code;
+  while (ptr--)
+    {
+      result->pathname = ptr ? includes[ptr - 1]->filename : original_pathname;
+      result->source_code = ptr ? includes[ptr - 1]->source_code : original_source_code;
+      NEW_ERROR_WITHOUT_INCLUDES(includes[ptr], NOTE, "included from here");
+    }
+  result->pathname = old_pathname;
+  result->source_code = old_source_code;
+  return 0;
+ pfail:
+  result->pathname = old_pathname;
+  result->source_code = old_source_code;
+  return -1;
+} 
+
+
+/**
+ * Mark the root of the tree as included
+ * 
+ * @param  result_  The `result` parameter of root procedure that requires the include stack
+ */
+void mds_kbdc_include_stack_begin(mds_kbdc_parsed_t* restrict result_)
+{
+  result = result_;
+  original_pathname = result_->pathname;
+  original_source_code = result_->source_code;
+}
+
+
+/**
+ * Mark the root of the tree as no longer being visited,
+ * and release clean up after the use of this module
+ * 
+ * This function is guaranteed not to modify `errno`
+ */
+void mds_kbdc_include_stack_end(void)
+{
+  int saved_errno = errno;
+  result->pathname = original_pathname;
+  result->source_code = original_source_code;
+  free(includes), includes = NULL;
+  includes_size = includes_ptr = 0;
+  errno = saved_errno;
+}
+
+
+/**
+ * Mark an include-statement as visited
+ * 
+ * @param   tree  The visisted include-statement
+ * @param   data  Output parameter with stack information that should be passed to
+ *                the corresponding call to `mds_kbdc_include_stack_pop`, `*data`
+ *                is undefined on error
+ * @return        Zero on success, -1 on error
+ */
+int mds_kbdc_include_stack_push(mds_kbdc_tree_include_t* restrict tree, void** data)
+{
+  mds_kbdc_tree_include_t** old = NULL;
+  int saved_errno;
+  
+  if (includes_ptr == includes_size)
+    fail_if (xxrealloc(old, includes, includes_size += 4, mds_kbdc_tree_include_t*));
+  
+  fail_if (xmalloc(*data, 2, void*));
+  
+  includes[includes_ptr++] = tree;
+  
+  ((char**)(*data))[0] = result->pathname;
+  ((mds_kbdc_source_code_t**)(*data))[1] = result->source_code;
+  
+  result->pathname = tree->filename;
+  result->source_code = tree->source_code;
+  
+  return 0;
+ pfail:
+  saved_errno = errno;
+  free(old);
+  return errno = saved_errno, -1;
+}
+
+
+/**
+ * Undo the lasted not-undone call to `mds_kbdc_include_stack_push`
+ * 
+ * This function is guaranteed not to modify `errno`
+ * 
+ * @param  data  `*data` from `mds_kbdc_include_stack_push`
+ */
+void mds_kbdc_include_stack_pop(void* data)
+{
+  int saved_errno = errno;
+  result->pathname = ((char**)data)[0];
+  result->source_code = ((mds_kbdc_source_code_t**)data)[1];
+  includes_ptr--;
+  free(data);
+  errno = saved_errno;
+}
+
diff --git a/src/mds-kbdc/include-stack.h b/src/mds-kbdc/include-stack.h
new file mode 100644
index 0000000..2c9fce8
--- /dev/null
+++ b/src/mds-kbdc/include-stack.h
@@ -0,0 +1,118 @@
+/**
+ * mds — A micro-display server
+ * Copyright © 2014  Mattias Andrée (maandree@member.fsf.org)
+ * 
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#ifndef MDS_MDS_KBDC_INCLUDE_STACK_H
+#define MDS_MDS_KBDC_INCLUDE_STACK_H
+
+
+#include "parsed.h"
+
+
+
+/**
+ * Add an error to the error list
+ * 
+ * @param  NODE:const mds_kbdc_tree_t*    The node the triggered the error
+ * @param  SEVERITY:identifier            * in `MDS_KBDC_PARSE_ERROR_*` to indicate severity
+ * @param  ...:const char*, ...           Error description format string and arguments
+ * @scope  error:mds_kbdc_parse_error_t*  Variable where the new error will be stored
+ */
+#define NEW_ERROR_WITHOUT_INCLUDES(NODE, SEVERITY, ...)			\
+  NEW_ERROR_(result, SEVERITY, 1, (NODE)->loc_line,			\
+	     (NODE)->loc_start, (NODE)->loc_end, 1, __VA_ARGS__)
+
+/**
+ * Add “included from here”-notes
+ * 
+ * @param  PTR:size_t  The number of “included from here”-notes
+ */
+#define DUMP_INCLUDE_STACK(PTR)			\
+  fail_if (mds_kbdc_include_stack_dump(PTR))
+
+/**
+ * Add an error with “included from here”-notes to the error list
+ * 
+ * @param  NODE:const mds_kbdc_tree_t*    The node the triggered the error
+ * @param  PTR:size_t                     The number of “included from here”-notes
+ * @param  SEVERITY:identifier            * in `MDS_KBDC_PARSE_ERROR_*` to indicate severity
+ * @param  ...:const char*, ...           Error description format string and arguments
+ * @scope  error:mds_kbdc_parse_error_t*  Variable where the new error will be stored
+ */
+#define NEW_ERROR_WITH_INCLUDES(NODE, PTR, SEVERITY, ...)	\
+  do								\
+    {								\
+      NEW_ERROR_WITHOUT_INCLUDES(NODE, SEVERITY, __VA_ARGS__);	\
+      DUMP_INCLUDE_STACK(PTR);					\
+    }								\
+  while (0)
+
+
+
+/**
+ * The number elements stored by `mds_kbdc_include_stack_push`
+ * but not removed by `mds_kbdc_include_stack_pop`
+ */
+extern size_t includes_ptr;
+
+
+
+/**
+ * Add “included from here”-notes
+ * 
+ * @param   ptr  The number of “included from here”-notes
+ * @return       Zero on success, -1 on error
+ */
+int mds_kbdc_include_stack_dump(size_t ptr);
+
+/**
+ * Mark the root of the tree as included
+ * 
+ * @param  result  The `result` parameter of root procedure that requires the include stack
+ */
+void mds_kbdc_include_stack_begin(mds_kbdc_parsed_t* restrict result);
+
+/**
+ * Mark the root of the tree as no longer being visited,
+ * and release clean up after the use of this module
+ * 
+ * This function is guaranteed not to modify `errno`
+ */
+void mds_kbdc_include_stack_end(void);
+
+/**
+ * Mark an include-statement as visited
+ * 
+ * @param   tree  The visisted include-statement
+ * @param   data  Output parameter with stack information that should be passed to
+ *                the corresponding call to `mds_kbdc_include_stack_pop`, `*data`
+ *                is undefined on error
+ * @return        Zero on success, -1 on error
+ */
+int mds_kbdc_include_stack_push(mds_kbdc_tree_include_t* restrict tree, void** data);
+
+/**
+ * Undo the lasted not-undone call to `mds_kbdc_include_stack_push`
+ * 
+ * This function is guaranteed not to modify `errno`
+ * 
+ * @param  data  `*data` from `mds_kbdc_include_stack_push`
+ */
+void mds_kbdc_include_stack_pop(void* data);
+
+
+#endif
+
diff --git a/src/mds-kbdc/validate-tree.c b/src/mds-kbdc/validate-tree.c
index 1bfbc9e..ed96343 100644
--- a/src/mds-kbdc/validate-tree.c
+++ b/src/mds-kbdc/validate-tree.c
@@ -17,6 +17,8 @@
  */
 #include "validate-tree.h"
 
+#include "include-stack.h"
+
 #include <stdlib.h>
 #include <errno.h>
 
@@ -28,26 +30,6 @@
 #define C(TYPE)  MDS_KBDC_TREE_TYPE_##TYPE
 
 /**
- * Add an error to the error list
- * 
- * @param  NODE:const mds_kbdc_tree_t*    The node the triggered the error
- * @param  SEVERITY:identifier            * in `MDS_KBDC_PARSE_ERROR_*` to indicate severity
- * @param  ...:const char*, ...           Error description format string and arguments
- * @scope  error:mds_kbdc_parse_error_t*  Variable where the new error will be stored
- */
-#define NEW_ERROR_WITHOUT_INCLUDES(NODE, SEVERITY, ...)			\
-  NEW_ERROR_(result, SEVERITY, 1, (NODE)->loc_line,			\
-	     (NODE)->loc_start, (NODE)->loc_end, 1, __VA_ARGS__)
-
-/**
- * Add “included from here”-notes
- * 
- * @param  PTR:size_t  The number of “included from here”-notes
- */
-#define DUMP_INCLUDE_STACK(PTR)		\
-  fail_if (dump_include_stack(PTR))
-
-/**
  * Add an error with “included from here”-notes to the error list
  * 
  * @param  NODE:const mds_kbdc_tree_t*    The node the triggered the error
@@ -57,12 +39,7 @@
  * @scope  error:mds_kbdc_parse_error_t*  Variable where the new error will be stored
  */
 #define NEW_ERROR(NODE, PTR, SEVERITY, ...)			\
-  do								\
-    {								\
-      NEW_ERROR_WITHOUT_INCLUDES(NODE, SEVERITY, __VA_ARGS__);	\
-      DUMP_INCLUDE_STACK(PTR);					\
-    }								\
-  while (0)
+  NEW_ERROR_WITH_INCLUDES(NODE, PTR, SEVERITY, __VA_ARGS__)
 
 
 
@@ -77,31 +54,6 @@ static mds_kbdc_parse_error_t* error;
 static mds_kbdc_parsed_t* restrict result;
 
 /**
- * The original value of `result->pathname`
- */
-static char* original_pathname;
-
-/**
- * The original value of `result->source_code`
- */
-static mds_kbdc_source_code_t* original_source_code;
-
-/**
- * Stack of visited include-statements
- */
-static mds_kbdc_tree_include_t** restrict includes = NULL;
-
-/**
- * The number elements allocated for `includes`
- */
-static size_t includes_size = 0;
-
-/**
- * The number elements stored in `includes`
- */
-static size_t includes_ptr = 0;
-
-/**
  * The number visited for-statements
  */
 static size_t fors = 0;
@@ -145,32 +97,6 @@ static int validate_subtree(mds_kbdc_tree_t* restrict tree);
 
 
 /**
- * Add “included from here”-notes
- * 
- * @param   ptr  The number of “included from here”-notes
- * @return       Zero on success, -1 on error
- */
-static int dump_include_stack(size_t ptr)
-{
-  char* old_pathname = result->pathname;
-  mds_kbdc_source_code_t* old_source_code = result->source_code;
-  while (ptr--)
-    {
-      result->pathname = ptr ? includes[ptr - 1]->filename : original_pathname;
-      result->source_code = ptr ? includes[ptr - 1]->source_code : original_source_code;
-      NEW_ERROR_WITHOUT_INCLUDES(includes[ptr], NOTE, "included from here");
-    }
-  result->pathname = old_pathname;
-  result->source_code = old_source_code;
-  return 0;
- pfail:
-  result->pathname = old_pathname;
-  result->source_code = old_source_code;
-  return -1;
-} 
-
-  
-/**
  * Validate an include-statement
  * 
  * @param   tree  The tree to validate
@@ -178,20 +104,13 @@ static int dump_include_stack(size_t ptr)
  */
 static int validate_include(mds_kbdc_tree_include_t* restrict tree)
 {
-  mds_kbdc_tree_include_t** old;
-  char* pathname = result->pathname;
-  mds_kbdc_source_code_t* source_code = result->source_code;
-  int r, saved_errno;
-  if (includes_ptr == includes_size)
-    if (xxrealloc(old, includes, includes_size += 4, mds_kbdc_tree_include_t*))
-      return saved_errno = errno, free(old), errno = saved_errno, -1;
-  includes[includes_ptr++] = tree;
-  result->pathname = tree->filename;
-  result->source_code = tree->source_code;
+  void* data;
+  int r;
+  if (mds_kbdc_include_stack_push(tree, &data))
+    return -1;
   r = validate_subtree(tree->inner);
-  result->pathname = pathname;
-  result->source_code = source_code;
-  return includes_ptr--, r;
+  mds_kbdc_include_stack_pop(data);
+  return r;
 }
 
 
@@ -579,24 +498,15 @@ static int validate_subtree(mds_kbdc_tree_t* restrict tree)
  */
 int validate_tree(mds_kbdc_parsed_t* restrict result_)
 {
-  int r, saved_errno;
-  result = result_;
-  original_pathname = result_->pathname;
-  original_source_code = result_->source_code;
+  int r;
+  mds_kbdc_include_stack_begin(result = result_);
   r = validate_subtree(result_->tree);
-  saved_errno = errno;
-  result_->pathname = original_pathname;
-  result_->source_code = original_source_code;
-  free(includes), includes = NULL;
-  includes_size = includes_ptr = 0;
   fors = 0;
-  return errno = saved_errno, r;
+  return mds_kbdc_include_stack_end(), r;
 }
 
 
 
 #undef NEW_ERROR
-#undef DUMP_INCLUDE_STACK
-#undef NEW_ERROR_WITHOUT_INCLUDES
 #undef C