/* Copyright (c) 2008 The Board of Trustees of The Leland Stanford
 * Junior University
 * 
 * We are making the OpenFlow specification and associated documentation
 * (Software) available for public use and benefit with the expectation
 * that others will use, modify and enhance the Software and contribute
 * those enhancements back to the community. However, since we would
 * like to make the Software available for broadest use, with as few
 * restrictions as possible permission is hereby granted, free of
 * charge, to any person obtaining a copy of this Software to deal in
 * the Software under the copyrights without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sublicense, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to
 * the following conditions:
 * 
 * The above copyright notice and this permission notice shall be
 * included in all copies or substantial portions of the Software.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT.  IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 * 
 * The name and trademarks of copyright holder(s) may NOT be used in
 * advertising or publicity pertaining to the Software or any
 * derivatives without specific, written prior permission.
 */

#include <config.h>
#include "util.h"
#include <errno.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

const char *program_name;

void
out_of_memory(void) 
{
    ofp_fatal(0, "virtual memory exhausted");
}

void *
xcalloc(size_t count, size_t size) 
{
    void *p = count && size ? calloc(count, size) : malloc(1);
    if (p == NULL) {
        out_of_memory();
    }
    return p;
}

void *
xmalloc(size_t size) 
{
    void *p = malloc(size ? size : 1);
    if (p == NULL) {
        out_of_memory();
    }
    return p;
}

void *
xrealloc(void *p, size_t size) 
{
    p = realloc(p, size ? size : 1);
    if (p == NULL) {
        out_of_memory();
    }
    return p;
}

void *
xmemdup(const void *p_, size_t size)
{
    void *p = xmalloc(size);
    memcpy(p, p_, size);
    return p;
}

char *
xmemdup0(const char *p_, size_t length)
{
    char *p = xmalloc(length + 1);
    memcpy(p, p_, length);
    p[length] = '\0';
    return p;
}

char *
xstrdup(const char *s) 
{
    return xmemdup0(s, strlen(s));
}

char *
xvasprintf(const char *format, va_list args)
{
    va_list args2;
    size_t needed;
    char *s;

    va_copy(args2, args);
    needed = vsnprintf(NULL, 0, format, args);

    s = xmalloc(needed + 1);

    vsnprintf(s, needed + 1, format, args2);
    va_end(args2);

    return s;
}

void *
x2nrealloc(void *p, size_t *n, size_t s)
{
    *n = *n == 0 ? 1 : 2 * *n;
    return xrealloc(p, *n * s);
}

char *
xasprintf(const char *format, ...)
{
    va_list args;
    char *s;

    va_start(args, format);
    s = xvasprintf(format, args);
    va_end(args);

    return s;
}

void
strlcpy(char *dst, const char *src, size_t size)
{
    if (size > 0) {
        size_t n = strlen(src);
        size_t n_copy = MIN(n, size - 1);
        memcpy(dst, src, n_copy);
        dst[n_copy] = '\0';
    }
}

void
ofp_fatal(int err_no, const char *format, ...)
{
    va_list args;

    fprintf(stderr, "%s: ", program_name);
    va_start(args, format);
    vfprintf(stderr, format, args);
    va_end(args);
    if (err_no != 0)
        fprintf(stderr, " (%s)", strerror(err_no));
    putc('\n', stderr);

    exit(EXIT_FAILURE);
}

void
ofp_error(int err_no, const char *format, ...)
{
    int save_errno = errno;
    va_list args;

    fprintf(stderr, "%s: ", program_name);
    va_start(args, format);
    vfprintf(stderr, format, args);
    va_end(args);
    if (err_no != 0)
        fprintf(stderr, " (%s)", strerror(err_no));
    putc('\n', stderr);

    errno = save_errno;
}

/* Sets program_name based on 'argv0'.  Should be called at the beginning of
 * main(), as "set_program_name(argv[0]);".  */
void set_program_name(const char *argv0)
{
    const char *slash = strrchr(argv0, '/');
    program_name = slash ? slash + 1 : argv0;
}

/* Writes the 'size' bytes in 'buf' to 'stream' as hex bytes arranged 16 per
 * line.  Numeric offsets are also included, starting at 'ofs' for the first
 * byte in 'buf'.  If 'ascii' is true then the corresponding ASCII characters
 * are also rendered alongside. */
void
ofp_hex_dump(FILE *stream, const void *buf_, size_t size,
             uintptr_t ofs, bool ascii)
{
  const uint8_t *buf = buf_;
  const size_t per_line = 16; /* Maximum bytes per line. */

  while (size > 0)
    {
      size_t start, end, n;
      size_t i;

      /* Number of bytes on this line. */
      start = ofs % per_line;
      end = per_line;
      if (end - start > size)
        end = start + size;
      n = end - start;

      /* Print line. */
      fprintf(stream, "%08jx  ", (uintmax_t) ROUND_DOWN(ofs, per_line));
      for (i = 0; i < start; i++)
        fprintf(stream, "   ");
      for (; i < end; i++)
        fprintf(stream, "%02hhx%c",
                buf[i - start], i == per_line / 2 - 1? '-' : ' ');
      if (ascii)
        {
          for (; i < per_line; i++)
            fprintf(stream, "   ");
          fprintf(stream, "|");
          for (i = 0; i < start; i++)
            fprintf(stream, " ");
          for (; i < end; i++) {
              int c = buf[i - start];
              putc(c >= 32 && c < 127 ? c : '.', stream);
          }
          for (; i < per_line; i++)
            fprintf(stream, " ");
          fprintf(stream, "|");
        }
      fprintf(stream, "\n");

      ofs += n;
      buf += n;
      size -= n;
    }
}