sha1_file.c

   1
   2 #include "cache.h"
   3
   4 static unsigned int pack_open_windows;
   5 static size_t pack_mapped;
   6 struct packed_git *packed_git;
   7
   8 static void scan_windows(struct packed_git *p,
   9         struct packed_git **lru_p,
  10         struct pack_window **lru_w,
  11         struct pack_window **lru_l)
  12 {
  13         struct pack_window *w, *w_l;
  14
  15         for (w_l = NULL, w = p->windows; w; w = w->next) {
  16                 if (!w->inuse_cnt) {
  17                         if (!*lru_w || w->last_used < (*lru_w)->last_used) {
  18                                 *lru_p = p;
  19                                 *lru_w = w;
  20                                 *lru_l = w_l;
  21                         }
  22                 }
  23                 w_l = w;
  24         }
  25 }
  26
  27 static int unuse_one_window(struct packed_git *current, int keep_fd)
  28 {
  29         struct packed_git *p, *lru_p = NULL;
  30         struct pack_window *lru_w = NULL, *lru_l = NULL;
  31
  32         if (current)
  33                 scan_windows(current, &lru_p, &lru_w, &lru_l);
  34         for (p = packed_git; p; p = p->next)
  35                 scan_windows(p, &lru_p, &lru_w, &lru_l);
  36         if (lru_p) {
  37                 munmap(lru_w->base, lru_w->len);
  38                 pack_mapped -= lru_w->len;
  39                 if (lru_l)
  40                         lru_l->next = lru_w->next;
  41                 else {
  42                         lru_p->windows = lru_w->next;
  43                         if (!lru_p->windows && lru_p->pack_fd != keep_fd) {
  44                                 close(lru_p->pack_fd);
  45                                 lru_p->pack_fd = -1;
  46                         }
  47                 }
  48                 free(lru_w);
  49                 pack_open_windows--;
  50                 return 1;
  51         }
  52         return 0;
  53 }
  54
  55 void release_pack_memory(size_t need, int fd)
  56 {
  57         size_t cur = pack_mapped;
  58         while (need >= (cur - pack_mapped) && unuse_one_window(NULL, fd))
  59                 ; /* nothing */
  60 }