/* Copyright (c) 2002-2018 Dovecot authors, see the included COPYING file */

#include "lib.h"

#include "buffer.h"

#include "printf-format-fix.h"

#include "unichar.h"

#include "str.h"

#include <stdio.h>

string_t *str_new(pool_t pool, size_t initial_size)

{

  /* never allocate a 0 byte size buffer. this is especially important

     when str_c() is called on an empty string from a different stack

     frame (see the comment in buffer.c about this). */

  return buffer_create_dynamic(pool, I_MAX(initial_size, 1));

}

string_t *str_new_const(pool_t pool, const char *str, size_t len)

{

  string_t *ret;

  i_assert(str[len] == '\0');

  ret = p_new(pool, buffer_t, 1);

  buffer_create_from_const_data(ret, str, len + 1);

  str_truncate(ret, len);

  return ret;

}

string_t *t_str_new(size_t initial_size)

{

  return str_new(pool_datastack_create(), initial_size);

}

string_t *t_str_new_const(const char *str, size_t len)

{

  return str_new_const(pool_datastack_create(), str, len);

}

void str_free(string_t **str)

{

  if (str == NULL || *str == NULL)

    return;

  buffer_free(str);

}

static void str_add_nul(string_t *str)

{

  const unsigned char *data = str_data(str);

  size_t len = str_len(str);

  size_t alloc = buffer_get_size(str);

  if (len == alloc || data[len] != '\0') {

    buffer_write(str, len, "", 1);

    /* remove the \0 - we don't want to keep it */

    buffer_set_used_size(str, len);

  }

}

char *str_free_without_data(string_t **str)

{

  str_add_nul(*str);

  return buffer_free_without_data(str);

}

const char *str_c(string_t *str)

{

  str_add_nul(str);

  return str->data;

}

char *str_c_modifiable(string_t *str)

{

  str_add_nul(str);

  return buffer_get_modifiable_data(str, NULL);

}

bool str_equals(const string_t *str1, const string_t *str2)

{

  if (str1->used != str2->used)

    return FALSE;

  return memcmp(str1->data, str2->data, str1->used) == 0;

}

void str_append_max(string_t *str, const char *cstr, size_t max_len)

{

  const char *p;

  size_t len;

  p = memchr(cstr, '\0', max_len);

  if (p == NULL)

    len = max_len;

  else

    len = p - (const char *)cstr;

  buffer_append(str, cstr, len);

}

void str_printfa(string_t *str, const char *fmt, ...)

{

  va_list args;

  va_start(args, fmt);

  str_vprintfa(str, fmt, args);

  va_end(args);

}

void str_vprintfa(string_t *str, const char *fmt, va_list args)

{

#define SNPRINTF_INITIAL_EXTRA_SIZE 128

  va_list args2;

  char *tmp;

  size_t init_size;

  size_t pos = str->used;

  int ret, ret2;

  VA_COPY(args2, args);

  /* the format string is modified only if %m exists in it. it happens

     only in error conditions, so don't try to t_push() here since it'll

     just slow down the normal code path. */

  fmt = printf_format_fix_get_len(fmt, &init_size);

  init_size += SNPRINTF_INITIAL_EXTRA_SIZE;

  /* @UNSAFE */

  if (pos+init_size > buffer_get_writable_size(str) &&

      pos < buffer_get_writable_size(str)) {

    /* avoid growing buffer larger if possible. this is also

       required if buffer isn't dynamically growing. */

    init_size = buffer_get_writable_size(str)-pos;

  }

  tmp = buffer_get_space_unsafe(str, pos, init_size);

  ret = vsnprintf(tmp, init_size, fmt, args);

  i_assert(ret >= 0);

  if ((unsigned int)ret >= init_size) {

    /* didn't fit with the first guess. now we know the size,

       so try again. */

    tmp = buffer_get_space_unsafe(str, pos, ret + 1);

    ret2 = vsnprintf(tmp, ret + 1, fmt, args2);

    i_assert(ret2 == ret);

  }

  va_end(args2);

  /* drop the unused data, including terminating NUL */

  buffer_set_used_size(str, pos + ret);

}

void str_truncate_utf8(string_t *str, size_t len)

{

  size_t size = str_len(str);

  if (size <= len)

    return;

  str_truncate(str, uni_utf8_data_truncate(str_data(str), size, len));

}