/*

 * Copyright (c) 2005 Stefan Walter

 * Copyright (c) 2011 Collabora Ltd.

 * Copyright (c) 2013 Red Hat Inc.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 *

 *     * Redistributions of source code must retain the above

 *       copyright notice, this list of conditions and the

 *       following disclaimer.

 *     * Redistributions in binary form must reproduce the

 *       above copyright notice, this list of conditions and

 *       the following disclaimer in the documentation and/or

 *       other materials provided with the distribution.

 *     * The names of contributors to this software may not be

 *       used to endorse or promote products derived from this

 *       software without specific prior written permission.

 *

 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS

 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT

 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS

 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE

 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,

 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,

 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS

 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED

 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,

 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF

 * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH

 * DAMAGE.

 *

 *

 * CONTRIBUTORS

 *  Stef Walter <stefw@redhat.com>

 */

#include "config.h"

#define P11_DEBUG_FLAG P11_DEBUG_CONF

#include "debug.h"

#include "lexer.h"

#include "message.h"

#include <assert.h>

#include <ctype.h>

#include <errno.h>

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

void

p11_lexer_init (p11_lexer *lexer,

                const char *filename,

                const char *data,

                size_t length)

{

  return_if_fail (lexer != NULL);

  memset (lexer, 0, sizeof (p11_lexer));

  lexer->at = data;

  lexer->remaining = length;

  return_if_fail (filename != NULL);

  lexer->filename = strdup (filename);

  return_if_fail (lexer->filename != NULL);

}

static void

clear_state (p11_lexer *lexer)

{

  switch (lexer->tok_type) {

  case TOK_FIELD:

    free (lexer->tok.field.name);

    free (lexer->tok.field.value);

    break;

  case TOK_SECTION:

    free (lexer->tok.section.name);

    break;

  case TOK_PEM:

  case TOK_EOF:

    break;

  }

  memset (&lexer->tok, 0, sizeof (lexer->tok));

  lexer->tok_type = TOK_EOF;

  lexer->complained = false;

}

bool

p11_lexer_next (p11_lexer *lexer,

                bool *failed)

{

  const char *colon;

  const char *value;

  const char *line;

  const char *end;

  const char *pos;

  char *part;

  return_val_if_fail (lexer != NULL, false);

  clear_state (lexer);

  if (failed)

    *failed = false;

  /* Go through lines and process them */

  while (lexer->remaining != 0) {

    assert (lexer->remaining > 0);

    /* Is this line the start of a PEM block? */

    if (strncmp (lexer->at, "-----BEGIN ", 11) == 0) {

      pos = strnstr (lexer->at, "\n-----END ", lexer->remaining);

      if (pos != NULL) {

        end = memchr (pos + 1, '\n', lexer->remaining - (pos - lexer->at) - 1);

        if (end)

          end += 1;

        else

          end = lexer->at + lexer->remaining;

        /* Count newlines in the PEM block */

        pos = lexer->at;

        while (pos < end) {

          pos = memchr (pos, '\n', end - pos);

          if (!pos)

            break;

          lexer->line++;

          pos++;

        }

        lexer->tok_type = TOK_PEM;

        lexer->tok.pem.begin = lexer->at;

        lexer->tok.pem.length = end - lexer->at;

        assert (end - lexer->at <= lexer->remaining);

        lexer->remaining -= (end - lexer->at);

        lexer->at = end;

        return true;

      }

      p11_lexer_msg (lexer, "invalid pem block: no ending line");

      if (failed)

        *failed = true;

      return false;

    }

    line = lexer->at;

    end = memchr (lexer->at, '\n', lexer->remaining);

    if (end == NULL) {

      end = lexer->at + lexer->remaining;

      lexer->remaining = 0;

      lexer->at = end;

    } else {

      assert ((end - lexer->at) + 1 <= lexer->remaining);

      lexer->line++;

      lexer->remaining -= (end - lexer->at) + 1;

      lexer->at = end + 1;

    }

    /* Strip whitespace from line */

    while (line != end && isspace (line[0]))

      ++line;

    while (line != end && isspace (*(end - 1)))

      --end;

    /* Empty lines / comments at start */

    if (line == end || line[0] == '#')

      continue;

    /* Is the the a section ? */

    if (line[0] == '[') {

      if (*(end - 1) != ']') {

        part = strndup (line, end - line);

        p11_lexer_msg (lexer, "invalid section header: missing braces");

        free (part);

        if (failed)

          *failed = true;

        return false;

      }

      lexer->tok_type = TOK_SECTION;

      lexer->tok.section.name = strndup (line + 1, (end - line) - 2);

      return_val_if_fail (lexer->tok.section.name != NULL, false);

      return true;

    }

    /* Look for the break between name: value on the same line */

    colon = memchr (line, ':', end - line);

    if (!colon) {

      part = strndup (line, end - line);

      p11_lexer_msg (lexer, "invalid field line: no colon");

      free (part);

      if (failed)

        *failed = true;

      return false;

    }

    /* Strip whitespace from name and value */

    value = colon + 1;

    while (value != end && isspace (value[0]))

      ++value;

    while (line != colon && isspace (*(colon - 1)))

      --colon;

    lexer->tok_type = TOK_FIELD;

    lexer->tok.field.name = strndup (line, colon - line);

    lexer->tok.field.value = strndup (value, end - value);

    return_val_if_fail (lexer->tok.field.name && lexer->tok.field.value, false);

    return true;

  }

  return false;

}

void

p11_lexer_done (p11_lexer *lexer)

{

  return_if_fail (lexer != NULL);

  clear_state (lexer);

  free (lexer->filename);

  memset (lexer, 0, sizeof (p11_lexer));

}

void

p11_lexer_msg (p11_lexer *lexer,

               const char *msg)

{

  return_if_fail (lexer != NULL);

  if (lexer->complained)

    return;

  switch (lexer->tok_type) {

  case TOK_FIELD:

    p11_message ("%s:%zu: %s: %s", lexer->filename, lexer->line,

                 lexer->tok.field.name, msg);

    break;

  case TOK_SECTION:

    p11_message ("%s:%zu: [%s]: %s", lexer->filename, lexer->line,

                 lexer->tok.section.name, msg);

    break;

  case TOK_PEM:

    p11_message ("%s:%zu: BEGIN ...: %s", lexer->filename,

           lexer->line, msg);

    break;

  default:

    p11_message ("%s:%zu: %s", lexer->filename, lexer->line, msg);

    break;

  }

  lexer->complained = true;

}