/*
    * utils - misc libubox utility functions
    *
    * Copyright (C) 2012 Felix Fietkau <nbd@openwrt.org>
    *
    * Permission to use, copy, modify, and/or distribute this software for any
    * purpose with or without fee is hereby granted, provided that the above
    * copyright notice and this permission notice appear in all copies.
    *
   * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
   * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
   * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
   * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
   * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
   * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
   * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
   */
  
  #include <sys/mman.h>
  #include <errno.h>
  #include <stdarg.h>
  #include <stdlib.h>
  #include <stdio.h>
  #include <string.h>
  #include "utils.h"
  
  #define foreach_arg(_arg, _addr, _len, _first_addr, _first_len) \
          for (_addr = (_first_addr), _len = (_first_len); \
                  _addr; \
                  _addr = va_arg(_arg, void **), _len = _addr ? va_arg(_arg, size_t) : 0)
  
  #define C_PTR_ALIGN     (sizeof(size_t))
  #define C_PTR_MASK      (-C_PTR_ALIGN)
  
  void *__calloc_a(size_t len, ...)
  {
          va_list ap, ap1;
          void *ret;
          void **cur_addr;
          size_t cur_len;
          size_t alloc_len = 0;
          char *ptr;
  
          va_start(ap, len);
  
          va_copy(ap1, ap);
          foreach_arg(ap1, cur_addr, cur_len, &ret, len) {
                  size_t aligned;
  
                  if (cur_len > SIZE_MAX - (C_PTR_ALIGN - 1)) {
                          va_end(ap1);
                          va_end(ap);
                          return NULL;
                  }
                  aligned = (cur_len + C_PTR_ALIGN - 1) & C_PTR_MASK;
                  if (aligned > SIZE_MAX - alloc_len) {
                          va_end(ap1);
                          va_end(ap);
                          return NULL;
                  }
                  alloc_len += aligned;
          }
          va_end(ap1);
  
          ptr = calloc(1, alloc_len);
          if (!ptr) {
                  va_end(ap);
                  return NULL;
          }
  
          alloc_len = 0;
          foreach_arg(ap, cur_addr, cur_len, &ret, len) {
                  *cur_addr = &ptr[alloc_len];
                  alloc_len += (cur_len + C_PTR_ALIGN - 1) & C_PTR_MASK;
          }
          va_end(ap);
  
          return ret;
  }
  
  #ifdef LIBUBOX_COMPAT_CLOCK_GETTIME
  #include <mach/mach_host.h>             /* host_get_clock_service() */
  #include <mach/mach_port.h>             /* mach_port_deallocate() */
  #include <mach/mach_init.h>             /* mach_host_self(), mach_task_self() */
  #include <mach/clock.h>                 /* clock_get_time() */
  
  static clock_serv_t clock_realtime;
  static clock_serv_t clock_monotonic;
  
  static void __constructor clock_name_init(void)
  {
          mach_port_t host_self = mach_host_self();
  
          host_get_clock_service(host_self, CLOCK_REALTIME, &clock_realtime);
          host_get_clock_service(host_self, CLOCK_MONOTONIC, &clock_monotonic);
  }
  
  static void __destructor clock_name_dealloc(void)
  {
         mach_port_t self = mach_task_self();
 
         mach_port_deallocate(self, clock_realtime);
         mach_port_deallocate(self, clock_monotonic);
 }
 
 int clock_gettime(int type, struct timespec *tv)
 {
         int retval = -1;
         mach_timespec_t mts;
 
         switch (type) {
                 case CLOCK_REALTIME:
                         retval = clock_get_time(clock_realtime, &mts);
                         break;
                 case CLOCK_MONOTONIC:
                         retval = clock_get_time(clock_monotonic, &mts);
                         break;
                 default:
                         goto out;
         }
 
         tv->tv_sec = mts.tv_sec;
         tv->tv_nsec = mts.tv_nsec;
 out:
         return retval;
 }
 
 #endif
 
 void *cbuf_alloc(unsigned int order)
 {
         char path[] = "/tmp/cbuf-XXXXXX";
         unsigned long size = cbuf_size(order);
         void *ret = NULL;
         int fd;
 
         fd = mkstemp(path);
         if (fd < 0)
                 return NULL;
 
         if (unlink(path))
                 goto close;
 
         if (ftruncate(fd, cbuf_size(order)))
                 goto close;
 
 #ifndef MAP_ANONYMOUS
 #define MAP_ANONYMOUS MAP_ANON
 #endif
 
         ret = mmap(NULL, size * 2, PROT_NONE, MAP_ANON | MAP_PRIVATE, -1, 0);
         if (ret == MAP_FAILED) {
                 ret = NULL;
                 goto close;
         }
 
         if (mmap(ret, size, PROT_READ | PROT_WRITE, MAP_FIXED | MAP_SHARED,
                  fd, 0) != ret ||
             mmap(ret + size, size, PROT_READ | PROT_WRITE,
                  MAP_FIXED | MAP_SHARED, fd, 0) != ret + size) {
                 munmap(ret, size * 2);
                 ret = NULL;
         }
 
 close:
         close(fd);
         return ret;
 }
 
 void cbuf_free(void *ptr, unsigned int order)
 {
         munmap(ptr, cbuf_size(order) * 2);
 }
 
 int mkdir_p(char *dir, mode_t mask)
 {
         char *l;
         int ret;
 
         ret = mkdir(dir, mask);
         if (!ret || errno == EEXIST)
                 return 0;
 
         if (ret && (errno != ENOENT))
                 return -1;
 
         l = strrchr(dir, '/');
         if (!l || l == dir)
                 return -1;
 
         *l = '\0';
 
         if (mkdir_p(dir, mask))
                 return -1;
 
         *l = '/';
 
         ret = mkdir(dir, mask);
         if (!ret || errno == EEXIST)
                 return 0;
         else
                 return -1;
 }
 

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