nmap/nsock/src/filespace.h

/***************************************************************************
 * filespace.h -- a simple mechanism for storing dynamic amounts of data   *
 * in a simple to use, and quick to append-to structure.                   *
 *                                                                         *
 ***********************IMPORTANT NSOCK LICENSE TERMS***********************
 *                                                                         *
 * The nsock parallel socket event library is (C) 1999-2012 Insecure.Com   *
 * LLC This library is free software; you may redistribute and/or          *
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 * may be willing to sell alternative licenses (contact                    *
 * sales@insecure.com ).                                                   *
 *                                                                         *
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 *                                                                         *
 ***************************************************************************/

/* $Id$ */

#ifndef FILESPACE_H
#define FILESPACE_H

#ifdef HAVE_CONFIG_H
#include "nsock_config.h"
#include "nbase_config.h"
#endif

#ifdef WIN32
#include "nbase_winconfig.h"
#endif

#include <stdlib.h>
#include <stdarg.h>
#if HAVE_STRING_H
#include <string.h>
#endif
#if HAVE_STRINGS_H
#include <strings.h>
#endif

#define FILESPACE_LENGTH(fs) ((fs)->current_size)
#define FILESPACE_STR(fs) ((fs)->str)

struct filespace {
  int current_size;
  int current_alloc;

  /* Current position in the filespace */
  char *pos;
  char *str;
};

/* If you want to express a length, use fscat() */
static inline int fs_rputs(const char *str, struct filespace *fs) {
  char *new_str;
  int len;

  len = (int)strlen(str);

  if (len + fs->current_size + 1 > fs->current_alloc) {
    fs->current_alloc =  MAX(fs->current_size * 2, fs->current_size + len  + 1000);

    new_str = (char *)safe_malloc(fs->current_alloc);
    memcpy(new_str, fs->str, fs->current_size);

    fs->pos = (fs->pos - fs->str) + new_str;
    if (fs->str)
      free(fs->str);
    fs->str = new_str;
  }
  memcpy(fs->str + fs->current_size, str, len);
  fs->current_size += len;
  fs->str[fs->current_size] = '\0';

  return 0;
}


static inline int fs_rvputs(struct filespace *fs,...) {
  va_list args;
  const char *x;

  va_start(args, fs);
  for (;;) {
    x = va_arg(args, const char *);
    if (x == NULL)
      break;

    if (fs_rputs(x,fs) == -1) {
      va_end(args);
      return -1;
    }
  }
  va_end(args);
  return 1;
}

/* Concatenate a string to the end of a filespace */
static inline int fscat(struct filespace *fs, const char *str, int len) {
  char *tmpstr;

  if (len < 0)
    return -1;
  if (len == 0)
    return 0;

  /*
  printf("fscat: current_alloc=%d; current_size=%d; len=%d\n", fs->current_alloc, fs->current_size, len);
  */

  if (fs->current_alloc - fs->current_size < len + 2) {
    fs->current_alloc = (int) (fs->current_alloc * 1.4 + 1 );
    fs->current_alloc += 100 + len;

    tmpstr = (char *)safe_malloc(fs->current_alloc);
    memcpy(tmpstr, fs->str, fs->current_size);

    fs->pos = (fs->pos - fs->str) + tmpstr;
    if (fs->str) free(fs->str);
    fs->str = tmpstr;
  }
  memcpy(fs->str + fs->current_size, str, len);

  fs->current_size += len;
  fs->str[fs->current_size] = '\0';
  return 0;
}

static inline int fs_rputc(int ch, struct filespace *fs) {
  char s[2];

  if (fs->current_size + 2 <= fs->current_alloc) {
    fs->str[fs->current_size] = ch;
    fs->current_size++;
    fs->str[fs->current_size] = '\0';
  } else {
    /* otherwise we use the ueber-technique of letting fscat handle it ...  umm
     * actually I don't know why we don't do this in all cases ... */
    s[0] = ch;
    s[1] = '\0';
    fscat(fs, s, 1);
  }
  return 0;
}


int filespace_init(struct filespace *fs, int initial_size);

int fs_prepend(char *str, int len, struct filespace *fs);

int fs_clear(struct filespace *fs);

int fs_free(struct filespace *fs);

#endif /* FILESPACE_H */