chdir-notify.c

   1 #include "git-compat-util.h"
   2 #include "abspath.h"
   3 #include "chdir-notify.h"
   4 #include "list.h"
   5 #include "path.h"
   6 #include "strbuf.h"
   7 #include "trace.h"
   8
   9 struct chdir_notify_entry {
  10         const char *name;
  11         chdir_notify_callback cb;
  12         void *data;
  13         struct list_head list;
  14 };
  15 static LIST_HEAD(chdir_notify_entries);
  16
  17 void chdir_notify_register(const char *name,
  18                            chdir_notify_callback cb,
  19                            void *data)
  20 {
  21         struct chdir_notify_entry *e = xmalloc(sizeof(*e));
  22         e->name = name;
  23         e->cb = cb;
  24         e->data = data;
  25         list_add_tail(&e->list, &chdir_notify_entries);
  26 }
  27
  28 static void reparent_cb(const char *name,
  29                         const char *old_cwd,
  30                         const char *new_cwd,
  31                         void *data)
  32 {
  33         char **path = data;
  34         char *tmp = *path;
  35
  36         if (!tmp)
  37                 return;
  38
  39         *path = reparent_relative_path(old_cwd, new_cwd, tmp);
  40         free(tmp);
  41
  42         if (name) {
  43                 trace_printf_key(&trace_setup_key,
  44                                  "setup: reparent %s to '%s'",
  45                                  name, *path);
  46         }
  47 }
  48
  49 void chdir_notify_reparent(const char *name, char **path)
  50 {
  51         chdir_notify_register(name, reparent_cb, path);
  52 }
  53
  54 int chdir_notify(const char *new_cwd)
  55 {
  56         struct strbuf old_cwd = STRBUF_INIT;
  57         struct list_head *pos;
  58
  59         if (strbuf_getcwd(&old_cwd) < 0)
  60                 return -1;
  61         if (chdir(new_cwd) < 0) {
  62                 int saved_errno = errno;
  63                 strbuf_release(&old_cwd);
  64                 errno = saved_errno;
  65                 return -1;
  66         }
  67
  68         trace_printf_key(&trace_setup_key,
  69                          "setup: chdir from '%s' to '%s'",
  70                          old_cwd.buf, new_cwd);
  71
  72         list_for_each(pos, &chdir_notify_entries) {
  73                 struct chdir_notify_entry *e =
  74                         list_entry(pos, struct chdir_notify_entry, list);
  75                 e->cb(e->name, old_cwd.buf, new_cwd, e->data);
  76         }
  77
  78         strbuf_release(&old_cwd);
  79         return 0;
  80 }
  81
  82 char *reparent_relative_path(const char *old_cwd,
  83                              const char *new_cwd,
  84                              const char *path)
  85 {
  86         char *ret, *full;
  87
  88         if (is_absolute_path(path))
  89                 return xstrdup(path);
  90
  91         full = xstrfmt("%s/%s", old_cwd, path);
  92         ret = xstrdup(remove_leading_path(full, new_cwd));
  93         free(full);
  94
  95         return ret;
  96 }