Refactoring in chapters

threads/bitmap.c

@@ -1,85 +0,0 @@
-#include "bitmap.h"
-#include <stdio.h>
-#include <stdlib.h>
-
-#ifdef bitmap_64
-#define bitmap_type unsigned long long int
-#define bitmap_shift 6
-#define bitmap_mask 63
-#define bitmap_wordlength 64
-#define bitmap_fmt "%016llx"
-#else // assumed to be 32 bits
-#define bitmap_type unsigned int
-#define bitmap_shift 5
-#define bitmap_mask 31
-#define bitmap_wordlength 32
-#define bitmap_fmt "%08x"
-#endif
-
-// get the types right
-#define bitmap_one (bitmap_type)1
-
-// we expect 0 <= n and n < b->bits, but it is not verified
-
-// arch a 8 bit
-// bitmap shift 3
-// wordlength 8
-
-// n = 10 -> 00001010
-// 00000001 -> word = 1
-//
-// n = 12 ->   00001100
-// mask = 7 -> 00000111
-//             00000100 = 4
-// 00000001 -> word = 1
-//
-// n = 32 ->    00100000
-// mask = 7 ->  00000111
-// 00000000
-// 00000100 -> word = 4
-//
-// n = 127 ->      01111111
-// mask = 7 ->     00000111
-// position = 7 -> 00000111
-//
-
-void bitmap_set(bitmap *b, int n) {
-  int word = n >> bitmap_shift;   // n / bitmap_wordlength
-  int position = n & bitmap_mask; // n % bitmap_wordlength
-  b->array[word] |= bitmap_one << position;
-}
-
-void bitmap_clear(bitmap *b, int n) {
-  int word = n >> bitmap_shift;   // n / bitmap_wordlength
-  int position = n & bitmap_mask; // n % bitmap_wordlength
-  b->array[word] &= ~(bitmap_one << position);
-}
-
-int bitmap_read(bitmap *b, int n) {
-  int word = n >> bitmap_shift;   // n / bitmap_wordlength
-  int position = n & bitmap_mask; // n % bitmap_wordlength
-  return (b->array[word] >> position) & 1;
-}
-
-bitmap *bitmap_allocate(int bits) {
-  // error-checking should be better :-)
-  bitmap *b = malloc(sizeof(bitmap));
-  b->bits = bits;
-  b->words = (bits + bitmap_wordlength - 1) / bitmap_wordlength;
-  // divide, but round up for the ceiling
-  b->array = calloc(b->words, sizeof(bitmap_type));
-  return b;
-}
-
-void bitmap_deallocate(bitmap *b) {
-  // error-checking should be better :-)
-  free(b->array);
-  free(b);
-}
-
-void bitmap_print(bitmap *b) {
-  for (int i = 0; i < b->words; i++) {
-    printf(" " bitmap_fmt, b->array[i]);
-  }
-  printf("\n");
-}

threads/bitmap.h

@@ -1,22 +0,0 @@
-// use dynamic allocation with these functions
-// compile with -Dbitmap_64 to force 64-bit words
-// compile with -O [dash capital o] for more efficient machine code
-
-#ifdef bitmap_64
-#define bitmap_type unsigned long long int
-#else // assumed to be 32 bits
-#define bitmap_type unsigned int
-#endif
-
-typedef struct {
-  int bits;  // number of bits in the array
-  int words; // number of words in the array
-  bitmap_type *array;
-} bitmap;
-
-void bitmap_set(bitmap *b, int n); // n is a bit index
-void bitmap_clear(bitmap *b, int n);
-int bitmap_read(bitmap *b, int n);
-bitmap *bitmap_allocate(int bits);
-void bitmap_deallocate(bitmap *b);
-void bitmap_print(bitmap *b);

threads/test.c

@@ -1,7 +0,0 @@
-#include <stdio.h>
-
-int main(void) {
-  int n;
-  printf("%d\n", n);
-  return 0;
-}

threads_chp4/pid_manager.h

@@ -0,0 +1,16 @@
+#if !defined(__PID_MANGER_H__)
+#define __PID_MANGER_H__
+#define _GNU_SOURCE
+
+// Crea e inizializza una struttura per rappresentare i pid;
+// restituisce -1 in caso di insuccesso e 1 in caso di successo.
+int allocate_map(void);
+
+// Alloca e restituisce un pid, restituisce -1 se non è possibile
+// assegnare un PID (tutti i pid sono in uso).
+int allocate_pid(void);
+
+// Rilascia un pid
+void release_pid(int pid);
+
+#endif