/* inih -- simple .INI file parser

inih is released under the New BSD license (see LICENSE.txt). Go to the project
home page for more info:

https://github.com/benhoyt/inih

*/

#if defined(_MSC_VER) && !defined(_CRT_SECURE_NO_WARNINGS)
#define _CRT_SECURE_NO_WARNINGS
#endif

#include <stdio.h>
#include <ctype.h>
#include <string.h>

#include "inih.h"

#if !INI_USE_STACK
#include <stdlib.h>
#endif

#define MAX_SECTION 50
#define MAX_NAME 50

/* Strip whitespace chars off end of given string, in place. Return s. */
static char* rstrip(char* s)
{
  char* p = s + strlen(s);
  while (p > s && isspace((unsigned char)(*--p)))
    *p = '\0';
  return s;
}

/* Return pointer to first non-whitespace char in given string. */
static char* lskip(const char* s)
{
  while (*s && isspace((unsigned char)(*s)))
    s++;
  return (char*)s;
}

/* Return pointer to first char (of chars) or inline comment in given string,
   or pointer to null at end of string if neither found. Inline comment must
   be prefixed by a whitespace character to register as a comment. */
static char* find_chars_or_comment(const char* s, const char* chars)
{
#if INI_ALLOW_INLINE_COMMENTS
  int was_space = 0;
  while (*s && (!chars || !strchr(chars, *s)) &&
         !(was_space && strchr(INI_INLINE_COMMENT_PREFIXES, *s)))
    {
      was_space = isspace((unsigned char)(*s));
      s++;
    }
#else
  while (*s && (!chars || !strchr(chars, *s)))
    {
      s++;
    }
#endif
  return (char*)s;
}

/* Version of strncpy that ensures dest (size bytes) is null-terminated. */
static char* strncpy0(char* dest, const char* src, size_t size)
{
  strncpy(dest, src, size);
  dest[size - 1] = '\0';
  return dest;
}

/* See documentation in header file. */
int ini_parse_stream(ini_reader reader, void* stream, ini_handler handler,
                     void* user)
{
  /* Uses a fair bit of stack (use heap instead if you need to) */
#if INI_USE_STACK
  char line[INI_MAX_LINE];
#else
  char* line;
#endif
  char section[MAX_SECTION] = "";
  char prev_name[MAX_NAME] = "";

  char* start;
  char* end;
  char* name;
  char* value;
  int lineno = 0;
  int error = 0;

#if !INI_USE_STACK
  line = (char*)malloc(INI_MAX_LINE);
  if (!line)
    {
      return -2;
    }
#endif

#if INI_HANDLER_LINENO
#define HANDLER(u, s, n, v) handler(u, s, n, v, lineno)
#else
#define HANDLER(u, s, n, v) handler(u, s, n, v)
#endif

  /* Scan through stream line by line */
  while (reader(line, INI_MAX_LINE, stream) != NULL)
    {
      lineno++;

      start = line;
#if INI_ALLOW_BOM
      if (lineno == 1 && (unsigned char)start[0] == 0xEF &&
          (unsigned char)start[1] == 0xBB &&
          (unsigned char)start[2] == 0xBF)
        {
          start += 3;
        }
#endif
      start = lskip(rstrip(start));

      if (*start == ';' || *start == '#')
        {
          /* Per Python configparser, allow both ; and # comments at the
             start of a line */
        }
#if INI_ALLOW_MULTILINE
      else if (*prev_name && *start && start > line)
        {
          /* Non-blank line with leading whitespace, treat as continuation
             of previous name's value (as per Python configparser). */
          if (!HANDLER(user, section, prev_name, start) && !error)
            error = lineno;
        }
#endif
      else if (*start == '[')
        {
          /* A "[section]" line */
          end = find_chars_or_comment(start + 1, "]");
          if (*end == ']')
            {
              *end = '\0';
              strncpy0(section, start + 1, sizeof(section));
              *prev_name = '\0';
#if INI_HANDLE_SECTION
              if (!HANDLER(user, section, NULL, NULL) && !error)
                error = lineno;
#endif
            }
          else if (!error)
            {
              /* No ']' found on section line */
              error = lineno;
            }
        }
      else if (*start)
        {
          /* Not a comment, must be a name[=:]value pair */
          end = find_chars_or_comment(start, "=:");
          if (*end == '=' || *end == ':')
            {
              *end = '\0';
              name = rstrip(start);
              value = end + 1;
#if INI_ALLOW_INLINE_COMMENTS
              end = find_chars_or_comment(value, NULL);
              if (*end)
                *end = '\0';
#endif
              value = lskip(value);
              rstrip(value);

              /* Valid name[=:]value pair found, call handler */
              strncpy0(prev_name, name, sizeof(prev_name));
              if (!HANDLER(user, section, name, value) && !error)
                error = lineno;
            }
          else
#if INI_HANDLE_EMPTY
            {
#if INI_ALLOW_INLINE_COMMENTS
              end = find_chars_or_comment(start, NULL);
              if (*end)
                *end = '\0';
#endif
              name = rstrip(start);
              if (*name && !strpbrk(name,"\t "))
                {
                  /* don't allow "named" names with whitespace*/
                  strncpy0(prev_name, name, sizeof(prev_name));
                  if (!HANDLER(user, section, name, NULL) && !error)
                    error = lineno;
                }
              else if (!error)
                error = lineno;
            }
#else
            if (!error)
              {
                /* No '=' or ':' found on name[=:]value line */
                error = lineno;
              }
#endif
        }

#if INI_STOP_ON_FIRST_ERROR
      if (error)
        break;
#endif
    }

#if !INI_USE_STACK
  free(line);
#endif

  return error;
}

/* See documentation in header file. */
int ini_parse_file(FILE* file, ini_handler handler, void* user)
{
  return ini_parse_stream((ini_reader)fgets, file, handler, user);
}

/* See documentation in header file. */
int ini_parse(const char* filename, ini_handler handler, void* user)
{
  FILE* file;
  int error;

  file = fopen(filename, "r");
  if (!file)
    return -1;
  error = ini_parse_file(file, handler, user);
  fclose(file);
  return error;
}
