code cleanup and optimization

Author: TwoUnderscorez

filesystem/bin/terminal

@@ -1,8 +1,8 @@
 global temp
 extern screen_print_int
 
-; NOTE: All I can only handle one interrupt at a time (for now) because 
-;	    I have one global ISR stack and not ISR stack per task because
+; NOTE: The syscall manager handles only one interrupt at a time (for now) 
+;	    because I have one global ISR stack and not ISR stack per task because
 ;		I didn't have enough time to debug that.
 
 ; ISR definition for interrupts without an err code

filesystem/kernel/kernel.sys

@@ -40,8 +40,8 @@ void ata_read_sectors(unsigned int lba, char sector_count, char *buffer) {
 	out_byte(ATA_COMMAND_REGISTER_PORT, ATA_READ); //read command
 	unsigned int offset = 0, i = 0;
 	while(sector_count--) {
-		ata_wait_for_rdy(ATA_REGULAR_STATUS_REGISTER_PORT);
-        ata_wait_for_drq(ATA_REGULAR_STATUS_REGISTER_PORT);
+		ata_wait_for_rdy(ATA_REGULAR_STATUS_REGISTER_PORT); // Spun up
+        ata_wait_for_drq(ATA_REGULAR_STATUS_REGISTER_PORT); // Ready for transfer
 		for(i = 0;i < 256;i++) {
 			*( (unsigned short *)buffer + offset + i ) = in_word(ATA_DATA_REGISTER_PORT);
 		}

src/asm/asmisr.asm

@@ -297,7 +297,7 @@ int path_to_inode(char * partial_path) {
         }
         i++;
     }
-    
+    free((void *)full_path);
     i = 0;
     return inode;
 }

src/drivers/atapio.c

@@ -205,6 +205,7 @@ static int elf_load_stage1(Elf32_Ehdr_t *hdr) {
 				puts("Allocated memory for a section "); 
 				screen_print_int(section->sh_size, 10);
 				puts("\n");
+				free(mem);
 			}
 		}
 	}
@@ -296,6 +297,9 @@ static void elf_init_exec(Elf32_Ehdr_t * hdr, int argc, char ** argv) {
 	swapPageDirectoryAsm((unsigned int *)pdpt_bk);
 	elf_task->regs.ebx = argc;
 	elf_task->regs.ecx = (unsigned int)argv_ptr2;
+	free(data);
+	free((void *)argv_mem_ptr);
+	free((void *)argv_ptr);
 } 
 
 void *elf_load_file(void *file, int argc, char ** argv) {

src/drivers/ext2.c

@@ -19,19 +19,29 @@ void *malloc(unsigned int size) {
     while((ptr != 0) && (ptr->used || ptr->length < size ) ){
         ptr = ptr->next;
     }
+    if((unsigned int)ptr > heap_end || (unsigned int)ptr < heap_start)
+    {
+        puts("Kernel out of memory.\n");
+        puts("[KERNEL PANIC] System halted :(");
+        while(1);   
+    }
     if(ptr->length == -1) {
         ptr->length = size;
         ptr->used = 1;
         ptr->next = ptr + size + sizeof(memory_block_header_t); 
+        if((unsigned int)ptr->next > heap_end || (unsigned int)ptr->next < heap_start)
+        {
+            puts("Kernel out of memory.\n");
+            puts("[KERNEL PANIC] System halted :(");
+            while(1);   
+        }
         ptr->next->length = -1;
         ptr->next->used = 0;
         ptr->next->next = 0;
     }
     else { 
         ptr->used = 1;
     }
-    if((unsigned int)ptr > heap_end)
-        return 0;
     retaddr = (void *)((unsigned int)ptr + sizeof(memory_block_header_t));
     memset(retaddr, 0, size);
     return retaddr;

src/kernel/elf.c

@@ -92,7 +92,7 @@ void isr_handler(registers_t regs)
 		}
 		else {
 			puts("[KERNEL PANIC] System halted :(");
-			getc();
+			while(1);
 		}
 	}
 }

src/kernel/heap.c

@@ -8,7 +8,7 @@ struct registers
 	unsigned int edi, esi, ebp, kesp, ebx, edx, ecx, eax;//
 	unsigned int int_no, err_code; 						 // Pushed by ISRs in asmisr.asm
 	unsigned int eip, cs, eflags, useresp, ss; 			 // Pushed by int opcode
-};
+}__attribute__((packed));
 
 typedef struct registers registers_t;
 

src/kernel/isr.c

@@ -29,23 +29,6 @@ void init_memory(multiboot_info_t * mymbd) {
         page_dir[i].page_table_address = (i*0x200000)>>12;
         page_dir[i].kernel_user = 0;
     }
-    ////////////////////////////////////////////////////////////////////////////
-    // An unsuccessful attempt at making a Higher Half Kernel
-    // unsigned int i, address = 0xB0000000;
-    // puts("\n");
-    // for(i = 388; i < 475; i++){
-    //     screen_print_int(address>>12, 16);
-    //     puts(" ");
-    //     page_dir[i].present = 1;
-    //     page_dir[i].ro_rw = 1;
-    //     page_dir[i].size = 1;
-    //     page_dir[i].page_table_address = (unsigned int)address>>12;
-    //     screen_print_int(page_dir[i].page_table_address, 16);
-    //     puts("\n");
-    //     getc();
-    //     page_dir[i].kernel_user = 0;
-    //     address = (unsigned int)((unsigned int)address + (unsigned int)0x200000);
-    // }
     puts("Enabaling PAE paging...\n");
     enablePaePagingAsm(); 
     swapPageDirectoryAsm((unsigned int *)&page_dir_ptr_tab);
@@ -206,7 +189,7 @@ unsigned int kalloc_frame()
     pframe++;
     // asmcli();
     disablePagingAsm();
-    memset((void *)ret, '\0', 0x1000);
+    memset((void *)ret, 0, 0x1000);
     enablePagingAsm();
     // asmsti();
     return(ret);