[PATCH 2/6] * variable.h: Add support of struct value_records and parent_records

[Macpaul Lin]

(struct parent_record): add struct parent_record,
for constructing variables dependencies.
(struct value_record): add struct value_record for record
each value is assigned to a variable.
(variable_name_extract): add support to extract variable name
with [$()] prefix.
(alloc_parent_record): a function allocate memory for a parent_record
(do_variable_definition): add a paremeter of parent_records which will keep
related parent_variable occured in conditional_line.
(try_variable_definition): add a paremeter of parent_records to make
parent_record be associaited when the variable is defined.

Signed-off-by: Macpaul Lin <address@hidden>
---
 variable.h | 27 +++++++++++++++++++++++++--
 1 file changed, 25 insertions(+), 2 deletions(-)

diff --git a/variable.h b/variable.h
index 3e2328a..03ba18b 100644
--- a/variable.h
+++ b/variable.h
@@ -47,6 +47,23 @@ enum variable_flavor
 #define EXP_COUNT_BITS  15      /* This gets all the bitfields into 32 bits */
 #define EXP_COUNT_MAX   ((1<<EXP_COUNT_BITS)-1)
 
+struct parent_record
+  {
+    struct variable *parent;    /* a pointer to a parent which defined
+                                   a value of a variable  */
+    struct parent_record *next; /* a pointer to next parent which defined
+                                   the same value  */
+  };
+
+struct value_record
+  {
+    char *value;                       /* defined value of a variable. */
+    struct parent_record *p_records;   /* a list of parents which defined
+                                          this value  */
+    struct value_record *next;         /* a pointer to next defined value */
+  };
+
+
 struct variable
   {
     char *name;                 /* Variable name.  */
@@ -78,6 +95,8 @@ struct variable
         v_ifset,                /* Export it if it has a non-default value.  */
         v_default               /* Decide in target_environment.  */
       } export ENUM_BITFIELD (2);
+    struct value_record *v_records;
+                                /* a list of defined values of this variable */
   };
 
 /* Structure that represents a variable set.  */
@@ -119,6 +138,7 @@ char *allocated_variable_expand_for_file (const char *line, 
struct file *file);
 #define allocated_variable_expand(line) \
   allocated_variable_expand_for_file (line, (struct file *) 0)
 char *expand_argument (const char *str, const char *end);
+char *variable_name_extract (char *p, char **ps);
 char *variable_expand_string (char *line, const char *string, long length);
 void install_variable_buffer (char **bufp, unsigned int *lenp);
 void restore_variable_buffer (char *buf, unsigned int len);
@@ -152,17 +172,20 @@ void print_file_variables (const struct file *file);
 void print_target_variables (const struct file *file);
 void merge_variable_set_lists (struct variable_set_list **to_list,
                                struct variable_set_list *from_list);
+struct parent_record *alloc_parent_record (struct variable *parent);
 struct variable *do_variable_definition (const gmk_floc *flocp,
                                          const char *name, const char *value,
                                          enum variable_origin origin,
                                          enum variable_flavor flavor,
-                                         int target_var);
+                                         int target_var,
+                                         struct parent_record *parents);
 char *parse_variable_definition (const char *line,
                                  struct variable *v);
 struct variable *assign_variable_definition (struct variable *v, const char 
*line);
 struct variable *try_variable_definition (const gmk_floc *flocp, const char 
*line,
                                           enum variable_origin origin,
-                                          int target_var);
+                                          int target_var,
+                                          struct parent_record *parents);
 void init_hash_global_variable_set (void);
 void hash_init_function_table (void);
 void define_new_function(const gmk_floc *flocp, const char *name,
-- 
1.9.1