better error handling + segfault safe frees

c/include/error.h

@@ -0,0 +1,12 @@
+#ifndef ERROR_H
+#define ERROR_H
+
+typedef enum {
+    VARIABLE_NULL=1,
+    SWITCH_NOT_MATCHED,
+    PARSE_ERROR,
+    FILE_ERROR,
+    ALLOC_FAILED
+} error_t;
+
+#endif

c/include/token.h

@@ -81,7 +81,7 @@ extern int yydebug;
 #if ! defined YYSTYPE && ! defined YYSTYPE_IS_DECLARED
 union YYSTYPE
 {
-#line 47 "src/parser.bison"
+#line 48 "src/parser.bison"
 
     struct expr *expr;
     struct oper *oper;

c/include/value.h

@@ -39,8 +39,8 @@ struct pure_value {
 struct value * value_create(addr_mode_t addr_m, index_t i_m, struct pure_value *value, struct ttk_register *i_reg);
 struct value * value_create_direct_value(struct pure_value *p_v);
 struct value * value_create_direct_indexed(struct pure_value *p_v, struct ttk_register *ttk_reg);
-struct value * value_create_address_mode_indexed(char addr_mode, struct pure_value *p_v, struct ttk_register *ttk_reg);
-struct value * value_create_address_mode(char addr_mode, struct pure_value *p_v);
+struct value * value_create_address_mode_indexed(char* addr_mode, struct pure_value *p_v, struct ttk_register *ttk_reg);
+struct value * value_create_address_mode(char* addr_mode, struct pure_value *p_v);
 struct value * value_create_direct_register(struct ttk_register *ttk_reg);
 
 
@@ -49,7 +49,7 @@ struct pure_value * pure_value_create_value(int value);
 struct pure_value * pure_value_create_label(struct label *l);
 
 struct pure_value * pure_value_create(value_t kind, struct ttk_register *ttk_reg, int num, struct label *l);
-addr_mode_t parse_addr_mode(char addr_mode);
+addr_mode_t parse_addr_mode(char* addr_mode);
 int value_print(struct value *v);
 
 

c/src/comment.c

@@ -1,6 +1,7 @@
 #include <stdlib.h>
 #include <stdio.h>
 #include <string.h>
+#include "error.h"
 #include "comment.h"
 
 struct comment * comment_create(char *text)
@@ -17,7 +18,7 @@ int comment_print(struct comment *c)
     if (!c || !c->text)
     {
         printf("\nERROR: Comment does not exist\n");
-        return 1;
+        return VARIABLE_NULL;
     }
 
     printf("%s", c->text);

c/src/expr.c

@@ -1,5 +1,6 @@
 #include <stdlib.h>
 #include <stdio.h>
+#include "error.h"
 #include "expr.h"
 
 #define PRINT_COMMENTS 1
@@ -63,69 +64,86 @@ struct expr *expr_create_comment(struct comment *c)
 int expr_print(struct expr *e)
 {
     if (!e)
-        return 1;
+        return VARIABLE_NULL;
 
     switch (e->kind)
     {
         case INSTRUCTION:
+        {
             if (e->label)
             {
-                if (label_print(e->label)!=0)
-                    return 1;;
+                int err = label_print(e->label);
+                if (err)
+                    return err;
                 printf(" ");
             }
 
-            if (oper_print(e->oper)!=0)
-                return 1;
+            int err = oper_print(e->oper);
+            if (err)
+                return err;
             printf(" ");
-            if (ttk_register_print(e->first_arg)!=0)
-                return 1;
+            err = ttk_register_print(e->first_arg);
+            if (err)
+                return err;
             printf(",");
             printf(" ");
-            if (value_print(e->second_arg)!=0)
-                return 1;
+            err = value_print(e->second_arg);
+            if (err)
+                return err;
             printf("\n");
             return 0;
+        }
 
         case INSTRUCTION_ONE_ARG:
+        {
             if (e->label)
             {
-                if (label_print(e->label)!=0)
-                    return 1;
+                int err = label_print(e->label);
+                if (err)
+                    return err;
                 printf(" ");
             }
 
-            if (oper_print(e->oper)!=0)
-                return 1;
+            int err = oper_print(e->oper);
+            if (err)
+                return err;
             printf(" ");
-            if (value_print(e->second_arg)!=0)
-                return 1;
+            err = value_print(e->second_arg);
+            if (err)
+                return err;
             printf("\n");
             return 0;
+        }
 
         case LABEL_DEF:
-            if (label_print(e->label)!=0)
-                return 1;
+        {
+            int err = label_print(e->label);
+            if (err)
+                return err;
             printf(" ");
-            if (oper_print(e->oper)!=0)
-                return 1;
+            err = oper_print(e->oper);
+            if (err)
+                return err;
             printf(" ");
-            if (value_print(e->second_arg)!=0)
-                return 1;
+            err = value_print(e->second_arg);
+            if (err)
+                return err;
             printf("\n");
             return 0;
+        }
 
         case COMMENT:
-            if (PRINT_COMMENTS == 1)
+            if (PRINT_COMMENTS)
                 return 0;
 
-            if (comment_print(e->comment)!=0)
-                return 1;
+            int err = comment_print(e->comment);
+            if (err)
+                return err;
             printf("\n");
             return 0;
 
         default:
-            return 1;
+            return SWITCH_NOT_MATCHED;
     }
 
 }
@@ -146,33 +164,31 @@ int expr_free(struct expr *e)
     switch (e->kind)
     {
         case INSTRUCTION:
-            if (e->label != NULL)
-                label_free(e->label);
-            oper_free(e->oper);
-            ttk_register_free(e->first_arg);
-            value_free(e->second_arg);
+            if (e->label) label_free(e->label);
+            if (e->oper) oper_free(e->oper);
+            if (e->first_arg) ttk_register_free(e->first_arg);
+            if (e->second_arg) value_free(e->second_arg);
             break;
 
         case INSTRUCTION_ONE_ARG:
-            if (e->label != NULL)
-                label_free(e->label);
-            oper_free(e->oper);
-            value_free(e->second_arg);
+            if (e->label) label_free(e->label);
+            if (e->oper) oper_free(e->oper);
+            if (e->second_arg) value_free(e->second_arg);
             break;
 
         case LABEL_DEF:
-            label_free(e->label);
-            oper_free(e->oper);
-            value_free(e->second_arg);
+            if (e->label) label_free(e->label);
+            if (e->oper) oper_free(e->oper);
+            if (e->second_arg) value_free(e->second_arg);
             break;
 
         case COMMENT:
-            comment_free(e->comment);
+            if (e->comment) comment_free(e->comment);
             break;
 
         default:
             printf("ERROR: Expr kind not matched while freeing\n");
-            return 1;
+            return SWITCH_NOT_MATCHED;
     }
 
     return 0;

c/src/label.c

@@ -1,6 +1,7 @@
 #include <stdlib.h>
 #include <string.h>
 #include <stdio.h>
+#include "error.h"
 #include "label.h"
 
 
@@ -27,7 +28,7 @@ int label_print(struct label *l)
     if (!l->name)
     {
         printf("ERROR: Label name doesn't exist.\n");
-        return 1;
+        return VARIABLE_NULL;
     }
 
     printf("%s", l->name);
@@ -36,6 +37,6 @@ int label_print(struct label *l)
 
 void label_free(struct label *l)
 {
-    free(l->name);
+    if (l->name) free(l->name);
     free(l);
 }

c/src/main.c

@@ -1,11 +1,12 @@
 #include <stdlib.h>
 #include <stdio.h>
+#include "error.h"
 #include "token.h"
 #include "program.h"
 
-#define FILENAME "../docs/example-file-harder.k91"
+//#define FILENAME "../docs/example-file-harder.k91"
 //#define FILENAME "../docs/example-file.k91"
-//#define FILENAME "../docs/example-file-simple.k91"
+#define FILENAME "../docs/example-file-simple.k91"
 
 // scanner
 extern FILE *yyin;
@@ -23,27 +24,27 @@ int main()
 
     if (!yyin) {
         printf("Couldn't open file\n");
-        return 1;
+        return FILE_ERROR;
     }
 
     struct expr *parse_result = malloc(sizeof(*parse_result));
     if (!parse_result)
     {
         printf("ERROR: Failed to allocate memory for parse_result.\n");
-        return 1;
+        return ALLOC_FAILED;
     }
 
 
     if (yyparse(parse_result) == 0) {
         printf("Parse succesful :)\n");
     } else {
-        printf("Parse failed\n");
         program_free(parse_result);
-        return 1;
+        return PARSE_ERROR;
     }
 
-    if (program_print(parse_result)!=0)
-        return 1;
+    int err = program_print(parse_result);
+    if (err!=0)
+        return err;
 
     program_free(parse_result);
     // TODO handle errors with assertions

c/src/oper.c

@@ -1,6 +1,7 @@
 #include <stdlib.h>
 #include <string.h>
 #include <stdio.h>
+#include "error.h"
 #include "oper.h"
 
 
@@ -9,7 +10,7 @@ struct oper * oper_create(oper_t kind, char* oper_name)
     struct oper *o = malloc(sizeof(*o));
 
     o->kind = kind;
-    o->oper_name = oper_name;
+    o->oper_name = oper_name; // TODO rename to just name just like everyone else xd
 
     return o;
 }
@@ -28,7 +29,7 @@ int oper_print(struct oper *o)
     if (!o)
     {
         printf("\nERROR: Null oper given.\n");
-        return 1;
+        return VARIABLE_NULL;
     }
 
     printf("%s", o->oper_name);
@@ -37,6 +38,6 @@ int oper_print(struct oper *o)
 
 void oper_free(struct oper *o)
 {
-    free(o->oper_name);
+    if (o->oper_name) free(o->oper_name);
     free(o);
 }

c/src/parser.bison

@@ -1,6 +1,7 @@
 /* TODO support tags to jump to different sections */
 %{
 #include <stdio.h>
+#include "error.h"
 #include "program.h"
 #include "comment.h"
 #include "expr.h"
@@ -67,8 +68,8 @@ int yyerror(struct expr *e, const char*);
 
 %type <name> TOKEN_REGISTER TOKEN_STACK_REGISTER
 %type <name> TOKEN_OPER_DATA TOKEN_OPER_AR TOKEN_OPER_LOGIC TOKEN_OPER_BRANCH TOKEN_OPER_STACK TOKEN_OPER_SYS TOKEN_COMP_OPER
-%type <name> TOKEN_LABEL TOKEN_SYS_NUM
-%type <character> TOKEN_PAREN_L TOKEN_PAREN_R TOKEN_ADDR_M TOKEN_SIGN
+%type <name> TOKEN_LABEL TOKEN_SYS_NUM TOKEN_ADDR_M
+%type <character> TOKEN_PAREN_L TOKEN_PAREN_R TOKEN_SIGN
 %type <num>  TOKEN_NUMBER
 %type <name> TOKEN_COMMENT
 
@@ -97,8 +98,8 @@ oper        : TOKEN_OPER_DATA                   { $$ = oper_create_data($1); }
             | TOKEN_OPER_SYS                    { $$ = oper_create_sys($1); }
             ;
 
-ttk_register: TOKEN_REGISTER                    { $$ = ttk_register_create_register($1); }
-            | TOKEN_STACK_REGISTER              { $$ = ttk_register_create_stack_register($1); }
+ttk_register: TOKEN_REGISTER                    { $$ = ttk_register_create_register($1); if (!$$) { yyerror(parse_result, "Token empty"); YYERROR;} }
+            | TOKEN_STACK_REGISTER              { $$ = ttk_register_create_stack_register($1); if (!$$) { yyerror(parse_result, "Token empty"); YYERROR;} }
             ;
 
 
@@ -127,6 +128,6 @@ num_value   : TOKEN_SIGN TOKEN_NUMBER           { $$ = -$2; }
 
 int yyerror ( struct expr *e, const char *s )
 {
-    printf("ERROR: Parser error: %s at line %d\n", s, yylineno);
-    return 1;
+    printf("Parser error: %s at line %d\n", s, yylineno);
+    return PARSE_ERROR;
 }

c/src/program.c

@@ -8,8 +8,9 @@ int program_print(struct expr *program)
 
     while (current != NULL)
     {
-        if (expr_print(current)!=0)
-            return 1;
+        int err = expr_print(current);
+        if (err!=0)
+            return err;
         current = current->next;
     }
 

c/src/ttk_register.c

@@ -1,14 +1,24 @@
 #include <stdlib.h>
 #include <stdio.h>
 #include <string.h>
+#include "error.h"
 #include "ttk_register.h"
 
 struct ttk_register * ttk_register_create(ttk_register_t kind, char* name, int value)
 {
+
+    int id = parse_register_num(name, kind);
+
+    if (id == -1)
+    {
+        printf("Register creation failed.\n");
+        return NULL;
+    }
+
     struct ttk_register * r = malloc(sizeof(*r));
 
     r->kind = kind;
-    r->id = parse_register_num(name, kind);
+    r->id = id;
     r->value = value;
 
     return r;
@@ -28,6 +38,7 @@ struct ttk_register * ttk_register_create_stack_register(char* name)
 int parse_register_num(char* name, ttk_register_t kind)
 {
     if (!name) {
+        printf("Name null while parsing register name.\n");
         return -1;
     }
 
@@ -49,6 +60,7 @@ int parse_register_num(char* name, ttk_register_t kind)
 
         default:
             free(name);
+            printf("Register type not matched while parsing register name.\n");
             return -1;
     }
 
@@ -60,8 +72,8 @@ int ttk_register_print(struct ttk_register *ttk_reg)
 {
     if (!ttk_reg || !ttk_reg->id)
     {
-        printf("ERROR: No ttk_register exists.\n");
-        return 1;
+        printf("ttk_register missing while trying to print it.\n");
+        return VARIABLE_NULL;
     }
     switch (ttk_reg->id)
     {
@@ -71,6 +83,8 @@ int ttk_register_print(struct ttk_register *ttk_reg)
         case 7:
             printf("FP");
             return 0;
+        default:
+            break;
     }
 
     printf("R%d", ttk_reg->id);

c/src/value.c

@@ -1,5 +1,6 @@
 #include <stdlib.h>
 #include <stdio.h>
+#include "error.h"
 #include "value.h"
 
 
@@ -31,12 +32,12 @@ struct value * value_create_direct_indexed(struct pure_value *p_v, struct ttk_re
     return value_create(DIRECT, INDEXED, p_v, ttk_reg);
 }
 
-struct value * value_create_address_mode_indexed(char addr_mode, struct pure_value *p_v, struct ttk_register *ttk_reg)
+struct value * value_create_address_mode_indexed(char* addr_mode, struct pure_value *p_v, struct ttk_register *ttk_reg)
 {
     return value_create(parse_addr_mode(addr_mode), INDEXED, p_v, ttk_reg);
 }
 
-struct value * value_create_address_mode(char addr_mode, struct pure_value *p_v)
+struct value * value_create_address_mode(char* addr_mode, struct pure_value *p_v)
 {
     return value_create(parse_addr_mode(addr_mode), NONE, p_v, NULL);
 }
@@ -60,9 +61,11 @@ struct pure_value * pure_value_create_value(int value)
 struct pure_value * pure_value_create_label(struct label *l)                        { return pure_value_create(LABEL, NULL, 0, l); }
 
 
-addr_mode_t parse_addr_mode(char addr_mode)
+addr_mode_t parse_addr_mode(char* addr_mode)
 {
-    switch (addr_mode)
+    if (!addr_mode)
+        return -1;
+    switch (addr_mode[0])
     {
         case '=':
             return IMMEDIATE;
@@ -79,23 +82,25 @@ int pure_value_print(struct pure_value *p_v)
     if (!p_v)
     {
         printf("\nERROR: Pure_value does not exist\n");
-        return 1;
+        return VARIABLE_NULL;
     }
 
     switch (p_v->kind)
     {
         case REGISTER:
             ttk_register_print(p_v->ttk_register);
-            return 0;
+            break;
         case NUMBER:
             printf("%d", p_v->number);
-            return 0;
+            break;
         case LABEL:
             label_print(p_v->label);
-            return 0;
+            break;
+        default:
+            return SWITCH_NOT_MATCHED;
     }
 
-    return 1;
+    return 0;
 }
 
 int value_print(struct value *v)
@@ -104,7 +109,7 @@ int value_print(struct value *v)
     if (!v)
     {
         printf("ERROR: Value not defined.\n");
-        return 1;
+        return VARIABLE_NULL;
     }
 
     // add = or @ to the beginnig of value
@@ -123,26 +128,39 @@ int value_print(struct value *v)
     switch (v->indexing_mode)
     {
         case NONE:
-            if (pure_value_print(v->value)!=0)
-                return 1;
-            return 0;
+        {
+            int err = pure_value_print(v->value);
+            if (err)
+                return err;
+            break;
+        }
         case INDEXED:
-            if (pure_value_print(v->value)!=0)
-                return 1;
+        {
+            int err = pure_value_print(v->value);
+            if (err)
+                return err;
             printf("(");
-            if (ttk_register_print(v->index_register)!=0)
-                return 1;
+            err = ttk_register_print(v->index_register); // is already defined
+            if (err)
+                return err;
             printf(")");
-            return 0;
+            break;
+
+        }
         case INDEXED_ONLY_IREG:
+        {
             printf("(");
-            if (ttk_register_print(v->index_register)!=0)
-                return 1;
+            int err = ttk_register_print(v->index_register);
+            if (err)
+                return err;
             printf(")");
-            return 0;
+            break;
+        }
+        default:
+            return SWITCH_NOT_MATCHED;
     }
 
-    return 1;
+    return 0;
 }
 
 void pure_value_free(struct pure_value *p_v)
@@ -150,12 +168,12 @@ void pure_value_free(struct pure_value *p_v)
     switch (p_v->kind)
     {
         case REGISTER:
-            ttk_register_free(p_v->ttk_register);
+            if (p_v->ttk_register) ttk_register_free(p_v->ttk_register);
             break;
         case NUMBER:
             break;
         case LABEL:
-            label_free(p_v->label);
+            if (p_v->label) label_free(p_v->label);
             break;
     }
     free(p_v);
@@ -166,15 +184,15 @@ void value_free(struct value *v)
     switch (v->indexing_mode)
     {
         case NONE:
-            pure_value_free(v->value);
+            if (v->value) pure_value_free(v->value);
             break;
         case INDEXED:
-            pure_value_free(v->value);
-            ttk_register_free(v->index_register);
+            if (v->value) pure_value_free(v->value);
+            if (v->index_register) ttk_register_free(v->index_register);
             break;
         default:
-            printf("ERROR: Value indexing mode not matched while freeing\n");
-            break;;
+            printf("ERROR: Indexing mode not matched while freeing value\n");
+            break;
     }
     free(v);
 }