/* -*- Mode: C; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 8 -*- */

/*

 * soup-headers.c: HTTP message header parsing

 *

 * Copyright (C) 2001-2003, Ximian, Inc.

 */

#ifdef HAVE_CONFIG_H

#include <config.h>

#endif

#include <stdlib.h>

#include <string.h>

#include "soup-misc.h"

#include "soup-headers.h"

#include "soup-message-headers-private.h"

#include "soup.h"

/**

 * soup_headers_parse:

 * @str: the header string (including the Request-Line or Status-Line,

 *   but not the trailing blank line)

 * @len: length of @str

 * @dest: #SoupMessageHeaders to store the header values in

 *

 * Parses the headers of an HTTP request or response in @str and

 * stores the results in @dest.

 *

 * Beware that @dest may be modified even on failure.

 *

 * This is a low-level method; normally you would use

 * [func@headers_parse_request] or [func@headers_parse_response].

 *

 * Returns: success or failure

 **/

gboolean

soup_headers_parse (const char *str, int len, SoupMessageHeaders *dest)

{

  const char *headers_start;

  char *headers_copy, *name, *name_end, *value, *value_end;

  char *eol, *sol, *p;

  gsize copy_len;

  gboolean success = FALSE;

  g_return_val_if_fail (str != NULL, FALSE);

  g_return_val_if_fail (dest != NULL, FALSE);

  /* As per RFC 2616 section 19.3, we treat '\n' as the

   * line terminator, and '\r', if it appears, merely as

   * ignorable trailing whitespace.

   */

  /* No '\0's are allowed */

  if (memchr (str, '\0', len))

    return FALSE;

  /* Skip over the Request-Line / Status-Line */

  headers_start = memchr (str, '\n', len);

  if (!headers_start)

    return FALSE;

  /* We work on a copy of the headers, which we can write '\0's

   * into, so that we don't have to individually g_strndup and

   * then g_free each header name and value.

   */

  copy_len = len - (headers_start - str);

  headers_copy = g_malloc (copy_len + 1);

  memcpy (headers_copy, headers_start, copy_len);

  headers_copy[copy_len] = '\0';

  value_end = headers_copy;

  while (*(value_end + 1)) {

    name = value_end + 1;

    name_end = strchr (name, ':');

    /* Reject if there is no ':', or the header name is

     * empty, or it contains whitespace.

     */

    if (!name_end ||

        name_end == name ||

        name + strcspn (name, " \t\r\n") < name_end) {

      /* Ignore this line. Note that if it has

       * continuation lines, we'll end up ignoring

       * them too since they'll start with spaces.

       */

      value_end = strchr (name, '\n');

      if (!value_end)

        goto done;

      continue;

    }

    /* Find the end of the value; ie, an end-of-line that

     * isn't followed by a continuation line.

     */

    value = name_end + 1;

    value_end = strchr (name, '\n');

    if (!value_end)

      goto done;

    while (*(value_end + 1) == ' ' || *(value_end + 1) == '\t') {

      value_end = strchr (value_end + 1, '\n');

      if (!value_end)

        goto done;

    }

    *name_end = '\0';

    *value_end = '\0';

    /* Skip leading whitespace */

    while (value < value_end &&

           (*value == ' ' || *value == '\t' ||

      *value == '\r' || *value == '\n'))

      value++;

    /* Collapse continuation lines */

    while ((eol = strchr (value, '\n'))) {

      /* find start of next line */

      sol = eol + 1;

      while (*sol == ' ' || *sol == '\t')

        sol++;

      /* back up over trailing whitespace on current line */

      while (eol[-1] == ' ' || eol[-1] == '\t' || eol[-1] == '\r')

        eol--;

      /* Delete all but one SP */

      *eol = ' ';

      memmove (eol + 1, sol, strlen (sol) + 1);

    }

    /* clip trailing whitespace */

    eol = strchr (value, '\0');

    while (eol > value &&

           (eol[-1] == ' ' || eol[-1] == '\t' || eol[-1] == '\r'))

      eol--;

    *eol = '\0';

    /* convert (illegal) '\r's to spaces */

    for (p = strchr (value, '\r'); p; p = strchr (p, '\r'))

      *p = ' ';

    soup_message_headers_append_untrusted_data (dest, name, value);

        }

  success = TRUE;

done:

  g_free (headers_copy);

  return success;

}

/**

 * soup_headers_parse_request:

 * @str: the headers (up to, but not including, the trailing blank line)

 * @len: length of @str

 * @req_headers: #SoupMessageHeaders to store the header values in

 * @req_method: (out) (optional): if non-%NULL, will be filled in with the

 *   request method

 * @req_path: (out) (optional): if non-%NULL, will be filled in with the

 *   request path

 * @ver: (out) (optional): if non-%NULL, will be filled in with the HTTP

 *   version

 *

 * Parses the headers of an HTTP request in @str and stores the

 * results in @req_method, @req_path, @ver, and @req_headers.

 *

 * Beware that @req_headers may be modified even on failure.

 *

 * Returns: %SOUP_STATUS_OK if the headers could be parsed, or an

 *   HTTP error to be returned to the client if they could not be.

 **/

guint

soup_headers_parse_request (const char          *str, 

          int                  len, 

          SoupMessageHeaders  *req_headers,

          char               **req_method,

          char               **req_path,

          SoupHTTPVersion     *ver) 

{

  const char *method, *method_end, *path, *path_end;

  const char *version, *version_end, *headers;

  unsigned long major_version, minor_version;

  char *p;

  g_return_val_if_fail (str != NULL, SOUP_STATUS_BAD_REQUEST);

  /* RFC 2616 4.1 "servers SHOULD ignore any empty line(s)

   * received where a Request-Line is expected."

   */

  while (len > 0 && (*str == '\r' || *str == '\n')) {

    str++;

    len--;

  }

  if (!len)

    return SOUP_STATUS_BAD_REQUEST;

  /* RFC 2616 19.3 "[servers] SHOULD accept any amount of SP or

   * HT characters between [Request-Line] fields"

   */

  method = method_end = str;

  while (method_end < str + len && *method_end != ' ' && *method_end != '\t')

    method_end++;

  if (method_end >= str + len)

    return SOUP_STATUS_BAD_REQUEST;

  path = method_end;

  while (path < str + len && (*path == ' ' || *path == '\t'))

    path++;

  if (path >= str + len)

    return SOUP_STATUS_BAD_REQUEST;

  path_end = path;

  while (path_end < str + len && *path_end != ' ' && *path_end != '\t')

    path_end++;

  if (path_end >= str + len)

    return SOUP_STATUS_BAD_REQUEST;

  version = path_end;

  while (version < str + len && (*version == ' ' || *version == '\t'))

    version++;

  if (version + 8 >= str + len)

    return SOUP_STATUS_BAD_REQUEST;

  if (strncmp (version, "HTTP/", 5) != 0 ||

      !g_ascii_isdigit (version[5]))

    return SOUP_STATUS_BAD_REQUEST;

  major_version = strtoul (version + 5, &p, 10);

  if (p + 1 >= str + len || *p != '.' || !g_ascii_isdigit (p[1]))

    return SOUP_STATUS_BAD_REQUEST;

  minor_version = strtoul (p + 1, &p, 10);

  version_end = p;

  if (major_version != 1)

    return SOUP_STATUS_HTTP_VERSION_NOT_SUPPORTED;

  if (minor_version > 1)

    return SOUP_STATUS_HTTP_VERSION_NOT_SUPPORTED;

  headers = version_end;

  while (headers < str + len && (*headers == '\r' || *headers == ' '))

    headers++;

  if (headers >= str + len || *headers != '\n')

    return SOUP_STATUS_BAD_REQUEST;

  // Ensure pointer location for Request-Line end matches location of 'headers'

  p = strchr(str, '\n');

  if (p != headers)

    return SOUP_STATUS_BAD_REQUEST;

  if (!soup_headers_parse (str, len, req_headers))

    return SOUP_STATUS_BAD_REQUEST;

  if (soup_message_headers_get_expectations (req_headers) &

      SOUP_EXPECTATION_UNRECOGNIZED)

    return SOUP_STATUS_EXPECTATION_FAILED;

  /* RFC 2616 14.10 */

  if (minor_version == 0)

    soup_message_headers_clean_connection_headers (req_headers);

  if (req_method)

    *req_method = g_strndup (method, method_end - method);

  if (req_path)

    *req_path = g_strndup (path, path_end - path);

  if (ver)

    *ver = (minor_version == 0) ? SOUP_HTTP_1_0 : SOUP_HTTP_1_1;

  return SOUP_STATUS_OK;

}

/**

 * soup_headers_parse_status_line:

 * @status_line: an HTTP Status-Line

 * @ver: (out) (optional): if non-%NULL, will be filled in with the HTTP

 *   version

 * @status_code: (out) (optional): if non-%NULL, will be filled in with

 *   the status code

 * @reason_phrase: (out) (optional): if non-%NULL, will be filled in with

 *   the reason phrase

 *

 * Parses the HTTP Status-Line string in @status_line into @ver,

 * @status_code, and @reason_phrase.

 *

 * @status_line must be terminated by either "\0" or "\r\n".

 *

 * Returns: %TRUE if @status_line was parsed successfully.

 **/

gboolean

soup_headers_parse_status_line (const char       *status_line,

        SoupHTTPVersion  *ver,

        guint            *status_code,

        char            **reason_phrase)

{

  unsigned long major_version, minor_version, code;

  const char *code_start, *code_end, *phrase_start, *phrase_end;

  char *p;

  g_return_val_if_fail (status_line != NULL, FALSE);

  if (strncmp (status_line, "HTTP/", 5) == 0 &&

      g_ascii_isdigit (status_line[5])) {

    major_version = strtoul (status_line + 5, &p, 10);

    if (*p != '.' || !g_ascii_isdigit (p[1]))

      return FALSE;

    minor_version = strtoul (p + 1, &p, 10);

    if (major_version != 1)

      return FALSE;

    if (minor_version > 1)

      return FALSE;

    if (ver)

      *ver = (minor_version == 0) ? SOUP_HTTP_1_0 : SOUP_HTTP_1_1;

  } else if (!strncmp (status_line, "ICY", 3)) {

    /* Shoutcast not-quite-HTTP format */

    if (ver)

      *ver = SOUP_HTTP_1_0;

    p = (char *)status_line + 3;

  } else

    return FALSE;

  code_start = p;

  while (*code_start == ' ' || *code_start == '\t')

    code_start++;

  code_end = code_start;

  while (*code_end >= '0' && *code_end <= '9')

    code_end++;

  if (code_end != code_start + 3)

    return FALSE;

  code = atoi (code_start);

  if (code < 100 || code > 999)

    return FALSE;

  if (status_code)

    *status_code = code;

  phrase_start = code_end;

  while (*phrase_start == ' ' || *phrase_start == '\t')

    phrase_start++;

  phrase_end = phrase_start + strcspn (phrase_start, "\n");

  while (phrase_end > phrase_start &&

         (phrase_end[-1] == '\r' || phrase_end[-1] == ' ' || phrase_end[-1] == '\t'))

    phrase_end--;

  if (reason_phrase)

    *reason_phrase = g_strndup (phrase_start, phrase_end - phrase_start);

  return TRUE;

}

/**

 * soup_headers_parse_response:

 * @str: the headers (up to, but not including, the trailing blank line)

 * @len: length of @str

 * @headers: #SoupMessageHeaders to store the header values in

 * @ver: (out) (optional): if non-%NULL, will be filled in with the HTTP

 *   version

 * @status_code: (out) (optional): if non-%NULL, will be filled in with

 *   the status code

 * @reason_phrase: (out) (optional): if non-%NULL, will be filled in with

 *   the reason phrase

 *

 * Parses the headers of an HTTP response in @str and stores the

 * results in @ver, @status_code, @reason_phrase, and @headers.

 *

 * Beware that @headers may be modified even on failure.

 *

 * Returns: success or failure.

 **/

gboolean

soup_headers_parse_response (const char          *str, 

           int                  len, 

           SoupMessageHeaders  *headers,

           SoupHTTPVersion     *ver,

           guint               *status_code,

           char               **reason_phrase)

{

  SoupHTTPVersion version;

  g_return_val_if_fail (str != NULL, FALSE);

  /* Workaround for broken servers that send extra line breaks

   * after a response, which we then see prepended to the next

   * response on that connection.

   */

  while (len > 0 && (*str == '\r' || *str == '\n')) {

    str++;

    len--;

  }

  if (!len)

    return FALSE;

  if (!soup_headers_parse (str, len, headers)) 

    return FALSE;

  if (!soup_headers_parse_status_line (str, 

               &version, 

               status_code, 

               reason_phrase))

    return FALSE;

  if (ver)

    *ver = version;

  /* RFC 2616 14.10 */

  if (version == SOUP_HTTP_1_0)

    soup_message_headers_clean_connection_headers (headers);

  return TRUE;

}

/*

 * Parsing of specific HTTP header types

 */

static const char *

skip_lws (const char *s)

{

  while (g_ascii_isspace (*s))

    s++;

  return s;

}

static const char *

unskip_lws (const char *s, const char *start)

{

  while (s > start && g_ascii_isspace (*(s - 1)))

    s--;

  return s;

}

static const char *

skip_delims (const char *s, char delim)

{

  /* The grammar allows for multiple delimiters */

  while (g_ascii_isspace (*s) || *s == delim)

    s++;

  return s;

}

static const char *

skip_item (const char *s, char delim)

{

  gboolean quoted = FALSE;

  const char *start = s;

  /* A list item ends at the last non-whitespace character

   * before a delimiter which is not inside a quoted-string. Or

   * at the end of the string.

   */

  while (*s) {

    if (*s == '"')

      quoted = !quoted;

    else if (quoted) {

      if (*s == '\\' && *(s + 1))

        s++;

    } else {

      if (*s == delim)

        break;

    }

    s++;

  }

  return unskip_lws (s, start);

}

static GSList *

parse_list (const char *header, char delim)

{

  GSList *list = NULL;

  const char *end;

  header = skip_delims (header, delim);

  while (*header) {

    end = skip_item (header, delim);

    list = g_slist_prepend (list, g_strndup (header, end - header));

    header = skip_delims (end, delim);

  }

  return g_slist_reverse (list);

}

/**

 * soup_header_parse_list:

 * @header: a header value

 *

 * Parses a header whose content is described by RFC2616 as `#something`.

 *

 * "something" does not itself contain commas, except as part of quoted-strings.

 *

 * Returns: (transfer full) (element-type utf8): a #GSList of

 *   list elements, as allocated strings

 **/

GSList *

soup_header_parse_list (const char *header)

{

  g_return_val_if_fail (header != NULL, NULL);

  return parse_list (header, ',');

}

typedef struct {

  char *item;

  double qval;

} QualityItem;

static int

sort_by_qval (const void *a, const void *b)

{

  QualityItem *qia = (QualityItem *)a;

  QualityItem *qib = (QualityItem *)b;

  if (qia->qval == qib->qval)

    return 0;

  else if (qia->qval < qib->qval)

    return 1;

  else

    return -1;

}

/**

 * soup_header_parse_quality_list:

 * @header: a header value

 * @unacceptable: (out) (optional) (transfer full) (element-type utf8): on

 *   return, will contain a list of unacceptable values

 *

 * Parses a header whose content is a list of items with optional

 * "qvalue"s (eg, Accept, Accept-Charset, Accept-Encoding,

 * Accept-Language, TE).

 *

 * If @unacceptable is not %NULL, then on return, it will contain the

 * items with qvalue 0. Either way, those items will be removed from

 * the main list.

 *

 * Returns: (transfer full) (element-type utf8): a #GSList of

 *   acceptable values (as allocated strings), highest-qvalue first.

 **/

GSList *

soup_header_parse_quality_list (const char *header, GSList **unacceptable)

{

  GSList *unsorted;

  QualityItem *array;

  GSList *sorted, *iter;

  char *semi;

  const char *param, *equal, *value;

  double qval;

  int n;

  g_return_val_if_fail (header != NULL, NULL);

  if (unacceptable)

    *unacceptable = NULL;

  unsorted = soup_header_parse_list (header);

  array = g_new0 (QualityItem, g_slist_length (unsorted));

  for (iter = unsorted, n = 0; iter; iter = iter->next) {

    qval = 1.0;

    for (semi = strchr (iter->data, ';'); semi; semi = strchr (semi + 1, ';')) {

      param = skip_lws (semi + 1);

      if (*param != 'q')

        continue;

      equal = skip_lws (param + 1);

      if (!equal || *equal != '=')

        continue;

      value = skip_lws (equal + 1);

      if (!value)

        continue;

      if (value[0] != '0' && value[0] != '1')

        continue;

      qval = (double)(value[0] - '0');

      if (value[0] == '0' && value[1] == '.') {

        if (g_ascii_isdigit (value[2])) {

          qval += (double)(value[2] - '0') / 10;

          if (g_ascii_isdigit (value[3])) {

            qval += (double)(value[3] - '0') / 100;

            if (g_ascii_isdigit (value[4]))

              qval += (double)(value[4] - '0') / 1000;

          }

        }

      }

      *semi = '\0';

      break;

    }

    if (qval == 0.0) {

      if (unacceptable) {

        *unacceptable = g_slist_prepend (*unacceptable,

                 g_steal_pointer (&iter->data));

      }

    } else {

      array[n].item = g_steal_pointer (&iter->data);

      array[n].qval = qval;

      n++;

    }

  }

  g_slist_free_full (unsorted, g_free);

  qsort (array, n, sizeof (QualityItem), sort_by_qval);

  sorted = NULL;

  while (n--)

    sorted = g_slist_prepend (sorted, array[n].item);

  g_free (array);

  return sorted;

}

/**

 * soup_header_free_list: (skip)

 * @list: a #GSList returned from [func@header_parse_list] or

 * [func@header_parse_quality_list]

 *

 * Frees @list.

 **/

void

soup_header_free_list (GSList *list)

{

  g_slist_free_full (list, g_free);

}

/**

 * soup_header_contains:

 * @header: An HTTP header suitable for parsing with

 *   [func@header_parse_list]

 * @token: a token

 *

 * Parses @header to see if it contains the token @token (matched

 * case-insensitively).

 *

 * Note that this can't be used with lists that have qvalues.

 *

 * Returns: whether or not @header contains @token

 **/

gboolean

soup_header_contains (const char *header, const char *token)

{

  const char *end;

  guint len;

  g_return_val_if_fail (header != NULL, FALSE);

  g_return_val_if_fail (token != NULL, FALSE);

  len = strlen (token);

  header = skip_delims (header, ',');

  while (*header) {

    end = skip_item (header, ',');

    if (end - header == len &&

        !g_ascii_strncasecmp (header, token, len))

      return TRUE;

    header = skip_delims (end, ',');

  }

  return FALSE;

}

static void

decode_quoted_string_inplace (GString *quoted_gstring)

{

  char *quoted_string = quoted_gstring->str;

  char *src, *dst;

  src = quoted_string + 1;

  dst = quoted_string;

  while (*src && *src != '"') {

    if (*src == '\\' && *(src + 1))

      src++;

    *dst++ = *src++;

  }

  *dst = '\0';

}

static gboolean

decode_rfc5987_inplace (GString *encoded_gstring)

{

  char *q, *decoded;

  gboolean iso_8859_1 = FALSE;

  const char *encoded_string = encoded_gstring->str;

  q = strchr (encoded_string, '\'');

  if (!q)

    return FALSE;

  if (g_ascii_strncasecmp (encoded_string, "UTF-8",

         q - encoded_string) == 0)

    ;

  else if (g_ascii_strncasecmp (encoded_string, "iso-8859-1",

              q - encoded_string) == 0)

    iso_8859_1 = TRUE;

  else

    return FALSE;

  q = strchr (q + 1, '\'');

  if (!q)

    return FALSE;

  decoded = g_uri_unescape_string (q + 1, NULL);

  if (decoded == NULL)

    return FALSE;

  if (iso_8859_1) {

    char *utf8 =  g_convert_with_fallback (decoded, -1, "UTF-8",

                   "iso-8859-1", "_",

                   NULL, NULL, NULL);

    g_free (decoded);

    if (!utf8)

      return FALSE;

    decoded = utf8;

  }

  g_string_assign (encoded_gstring, decoded);

  g_free (decoded);

  return TRUE;

}

static GHashTable *

parse_param_list (const char *header, char delim, gboolean strict)

{

  GHashTable *params;

  GSList *list, *iter;

  params = g_hash_table_new_full (soup_str_case_hash, 

          soup_str_case_equal,

          g_free, g_free);

  list = parse_list (header, delim);

  for (iter = list; iter; iter = iter->next) {

    char *item, *eq, *name_end;

    gboolean override, duplicated;

    GString *parsed_value = NULL;

    item = iter->data;

    override = FALSE;

    eq = strchr (item, '=');

    if (eq) {

      name_end = (char *)unskip_lws (eq, item);

      if (name_end == item) {

        /* That's no good... */

        g_free (item);

        continue;

      }

      *name_end = '\0';

      parsed_value = g_string_new ((char *)skip_lws (eq + 1));

      if (name_end[-1] == '*' && name_end > item + 1) {

        name_end[-1] = '\0';

        if (!decode_rfc5987_inplace (parsed_value)) {

          g_string_free (parsed_value, TRUE);

          g_free (item);

          continue;

        }

        override = TRUE;

      } else if (parsed_value->str[0] == '"')

        decode_quoted_string_inplace (parsed_value);

    }

    duplicated = g_hash_table_lookup_extended (params, item, NULL, NULL);

    if (strict && duplicated) {

      soup_header_free_param_list (params);

      params = NULL;

      g_slist_foreach (iter, (GFunc)g_free, NULL);

      if (parsed_value)

        g_string_free (parsed_value, TRUE);

      break;

    } else if (override || !duplicated) {

      g_hash_table_replace (params, item, parsed_value ? g_string_free (parsed_value, FALSE) : NULL);

    } else {

      if (parsed_value)

        g_string_free (parsed_value, TRUE);

      g_free (item);

    }

  }

  g_slist_free (list);

  return params;

}

/**

 * soup_header_parse_param_list:

 * @header: a header value

 *

 * Parses a header which is a comma-delimited list of something like:

 * `token [ "=" ( token | quoted-string ) ]`.

 *

 * Tokens that don't have an associated value will still be added to

 * the resulting hash table, but with a %NULL value.

 * 

 * This also handles RFC5987 encoding (which in HTTP is mostly used

 * for giving UTF8-encoded filenames in the Content-Disposition

 * header).

 *

 * Returns: (element-type utf8 utf8) (transfer full): a

 *   #GHashTable of list elements, which can be freed with

 *   [func@header_free_param_list].

 **/

GHashTable *

soup_header_parse_param_list (const char *header)

{

  g_return_val_if_fail (header != NULL, NULL);

  return parse_param_list (header, ',', FALSE);

}

/**

 * soup_header_parse_semi_param_list:

 * @header: a header value

 *

 * Parses a header which is a semicolon-delimited list of something

 * like: `token [ "=" ( token | quoted-string ) ]`.

 *

 * Tokens that don't have an associated value will still be added to

 * the resulting hash table, but with a %NULL value.

 * 

 * This also handles RFC5987 encoding (which in HTTP is mostly used

 * for giving UTF8-encoded filenames in the Content-Disposition

 * header).

 *

 * Returns: (element-type utf8 utf8) (transfer full): a

 *   #GHashTable of list elements, which can be freed with

 *   [func@header_free_param_list].

 **/

GHashTable *

soup_header_parse_semi_param_list (const char *header)

{

  g_return_val_if_fail (header != NULL, NULL);

  return parse_param_list (header, ';', FALSE);

}

/**

 * soup_header_parse_param_list_strict:

 * @header: a header value

 *

 * A strict version of [func@header_parse_param_list]

 * that bails out if there are duplicate parameters.

 *

 * Note that this function will treat RFC5987-encoded

 * parameters as duplicated if an ASCII version is also

 * present. For header fields that might contain

 * RFC5987-encoded parameters, use

 * [func@header_parse_param_list] instead.

 *

 * Returns: (element-type utf8 utf8) (transfer full) (nullable):

 *   a #GHashTable of list elements, which can be freed with

 *   [func@header_free_param_list] or %NULL if there are duplicate

 *   elements.

 **/

GHashTable *

soup_header_parse_param_list_strict (const char *header)

{

  g_return_val_if_fail (header != NULL, NULL);

  return parse_param_list (header, ',', TRUE);

}

/**

 * soup_header_parse_semi_param_list_strict:

 * @header: a header value

 *

 * A strict version of [func@header_parse_semi_param_list]

 * that bails out if there are duplicate parameters.

 *

 * Note that this function will treat RFC5987-encoded

 * parameters as duplicated if an ASCII version is also

 * present. For header fields that might contain

 * RFC5987-encoded parameters, use

 * [func@header_parse_semi_param_list] instead.

 *

 * Returns: (element-type utf8 utf8) (transfer full) (nullable):

 *   a #GHashTable of list elements, which can be freed with

 *   [func@header_free_param_list] or %NULL if there are duplicate

 *   elements.

 **/

GHashTable *

soup_header_parse_semi_param_list_strict (const char *header)

{

  g_return_val_if_fail (header != NULL, NULL);

  return parse_param_list (header, ';', TRUE);

}

/**

 * soup_header_free_param_list:

 * @param_list: (element-type utf8 utf8): a #GHashTable returned from

 *   [func@header_parse_param_list] or [func@header_parse_semi_param_list]

 *

 * Frees @param_list.

 **/

void

soup_header_free_param_list (GHashTable *param_list)

{

  g_return_if_fail (param_list != NULL);

  g_hash_table_destroy (param_list);

}

static void

append_param_rfc5987 (GString    *string,

          const char *name,

          const char *value)

{

  char *encoded;

  g_string_append (string, name);

  g_string_append (string, "*=UTF-8''");

  encoded = g_uri_escape_string (value, "!#$&+-.^_`|~", FALSE);

  g_string_append (string, encoded);

  g_free (encoded);

}

static void

append_param_quoted (GString    *string,

         const char *name,

         const char *value)

{

  gsize len;

  g_string_append (string, name);

  g_string_append (string, "=\"");

  while (*value) {

    while (*value == '\\' || *value == '"') {

      g_string_append_c (string, '\\');

      g_string_append_c (string, *value++);

    }

    len = strcspn (value, "\\\"");

    g_string_append_len (string, value, len);

    value += len;

  }

  g_string_append_c (string, '"');

}

static void

append_param_internal (GString    *string,

           const char *name,

           const char *value,

           gboolean    allow_token)

{

  const char *v;

  gboolean use_token = allow_token;

  for (v = value; *v; v++) {

    if (*v & 0x80) {