tasking: add brk to process struct

include/task.h

@@ -66,6 +66,8 @@ typedef struct Process
 
     file_t* file_descriptors[MAX_OPEN_FILES];
     dir_t* cwd;
+
+    void* brk;
 } Process;
 
 extern Process* current;

src/tasking/exec_from_file.c

@@ -53,6 +53,8 @@ void exec_from_file(const char* filename, const char* dirname)
     uint8_t* file;
     dir_t dir;
 
+    uint32_t bss_start, bss_end;
+
     int result = read_file(filename, &file, &dir);
     //debug_log("result: %X\n", result);
     //debug_log("buffer: %s\n", file);
@@ -100,8 +102,8 @@ void exec_from_file(const char* filename, const char* dirname)
         memcpy((void*)elf_phdr->p_vaddr, file+elf_phdr->p_offset, elf_phdr->p_filesz);
         
         if (elf_phdr->p_memsz > elf_phdr->p_filesz) {
-            uint32_t bss_start = elf_phdr->p_vaddr + elf_phdr->p_filesz;
+            bss_start = elf_phdr->p_vaddr + elf_phdr->p_filesz;
-            uint32_t bss_end = elf_phdr->p_vaddr + elf_phdr->p_memsz;
+            bss_end = elf_phdr->p_vaddr + elf_phdr->p_memsz;
             memset((void*)bss_start, 0, bss_end - bss_start);
         }
 
@@ -109,6 +111,8 @@ void exec_from_file(const char* filename, const char* dirname)
         //debug_log("================================\n\n\n\n");
     }
 
+    debug_log("BSS: %X - %X (%X)\n", bss_start, bss_end, DivRoundUp(bss_end+1, 0x1000));
+    
     debug_log("setting up the user stack...\n");
 
     //TODO: i think this thing allocates more pages than needed
@@ -145,5 +149,8 @@ void exec_from_file(const char* filename, const char* dirname)
     Process* p_task1 = task_create(elf_ehdr->e_entry, USER_STACK_TOP, 3, proc_pd);
     *p_task1->cwd = dir;
 
+    uint32_t brk_address = DivRoundUp(bss_end+1, 0x1000)*0x1000;
+    p_task1->brk = (void*)brk_address;
+    
     asm volatile("sti");
 }