Removal label table global var (#14)

* Made variables private

This change made the previosuly global `label_table` and the other
`lable_table_size` variables static and added "getter" (Well, C do-
es not have getters) functions that *gets* the values of the label
table values and it's size.

So, having the `label_table` and `label_table_size` variables hid-
den away prevents mistakes by both the caller and internal functions
that may accidentally: 1. redefine or attempt to clash with the
variable names, and 2. unintentionally modify values of the label
table's values. (So, basically, you can't be stupid enough to even
attempt to modify a function's value)

* Added declaration to headaer

This change added in the function defined and added in commit nu-
mber 19dbeef and chucked it into
the `label.c`'s corrisponding header file.

* Changed source of labels of `label_table` users

Migrated the "users" (The places where the `label_table` and the
corrisponding `label_table_size` gets called and used) to the more
secure and safe `label_get_size()` and `label_get_table()` functions
as added in commit number 19dbeef

* Removed `inline` keyword

Turns out the inline keyword requires an alternate implementation
of the same function, therfore rendering this function undefined
during link time. However when the compiler deems needed, the com-
iler itself can *automatically inline* the as it deem fit during
compile time without us explicitly specifying it in the function
prototype. - I mean you learn something every day, huh?

README.md

@@ -1,4 +1,4 @@
-<!-- ![](https://github.com/cheng-alvin/jas/blob/main/logo.png) -->
+<!-- ![Jas logo](https://github.com/cheng-alvin/jas/blob/main/logo.png) -->
 ![Jas logo -  Christmas edition](https://github.com/user-attachments/assets/804d9479-77d2-4342-8f54-500a5f9d09fa)
 <p align="center">
 

libjas/codegen.c

@@ -108,6 +108,10 @@ buffer_t codegen(enum modes mode, instruction_t *instr_arr, size_t arr_size, enu
   free(section_ent.data);
   free(pad);
 
+  //!! DO NOT try and modify these - Please dont spoof me through pointer arithmetic as well :)
+  const size_t label_table_size = label_get_size();
+  const label_t *label_table = label_get_table();
+
   for (size_t i = 0; i < label_table_size; i++) {
     // Refer to https://www.sco.com/developers/devspecs/gabi41.pdf - Figure 4-16
     uint8_t binding = 0;
@@ -156,9 +160,10 @@ static buffer_t assemble(enum modes mode, instruction_t *instr_arr, size_t arr_s
         buf_write(&buf, data->data, data->len);
       }
       if (is_pre && IS_LABEL) {
-        for (size_t j = 0; j < label_table_size; j++) {
-          if (strcmp(label_table[j].name, instr_arr[i].operands[0].data) == 0) {
-            label_table[j].address = buf.len;
+        for (size_t j = 0; j < label_get_size; j++) {
+          label_t *tab = label_get_table();
+          if (strcmp(tab[j].name, instr_arr[i].operands[0].data) == 0) {
+            tab[j].address = buf.len;
             break;
           }
         }

libjas/exe.c

@@ -111,7 +111,7 @@ buffer_t exe_sect_header(uint32_t str_offset, uint32_t type, uint64_t flags, uin
 
   if (type == 0x02) {
     buf_write(&ret, &(uint32_t){2}, 4);                    // Section link
-    buf_write(&ret, &(uint32_t){label_table_size + 1}, 4); // Section info
+    buf_write(&ret, &(uint32_t){label_get_size() + 1}, 4); // Section info
     buf_write(&ret, QWORD_PAD, 8);                         // Section address alignment
     buf_write(&ret, &(uint64_t){0x18}, 8);                 // Section entry size
 

libjas/include/label.h

@@ -62,8 +62,8 @@ typedef struct {
   size_t instr_index; /* Index to slip the label in the instruction array */
 } label_t;
 
-extern label_t *label_table;
-extern size_t label_table_size;
+size_t label_get_size();
+label_t *label_get_table();
 
 /**
  * Function for destroying the label table, freeing the memory

libjas/label.c

@@ -29,8 +29,8 @@
 #include <stdlib.h>
 #include <string.h>
 
-label_t *label_table = NULL;
-size_t label_table_size = 0;
+static label_t *label_table = NULL;
+static size_t label_table_size = 0;
 
 void label_create(char *name, bool exported, bool ext, size_t address, size_t instr_index) {
   if (label_lookup(name) != NULL) {
@@ -39,11 +39,11 @@ void label_create(char *name, bool exported, bool ext, size_t address, size_t in
   }
 
   label_t label = {
-    .name = name,
-    .exported = exported, 
-    .ext = ext, .address = address, 
-    .instr_index = instr_index
-  };
+      .name = name,
+      .exported = exported,
+      .ext = ext,
+      .address = address,
+      .instr_index = instr_index};
 
   label_table_size++;
   label_table = (label_t *)realloc(label_table, label_table_size * sizeof(label_t));
@@ -64,3 +64,6 @@ label_t *label_lookup(char *name) {
 
   return NULL;
 }
+
+size_t label_get_size() { return label_table_size; }
+label_t *label_get_table() { return label_table; }