path.c

subversion-1.4.5.tar.gz 配置svn的源码

  
/* URI-encode each character c in PATH for which TABLE[c] is 0.
   If no encoding was needed, return PATH, else return a new string allocated
   in POOL. */
static const char *
uri_escape(const char *path, const char table[], apr_pool_t *pool)
{
  svn_stringbuf_t *retstr;
  apr_size_t i, copied = 0;
  int c;

  retstr = svn_stringbuf_create("", pool);
  for (i = 0; path[i]; i++)
    {
      c = (unsigned char)path[i];
      if (table[c])
        continue;

      /* If we got here, we're looking at a character that isn't
         supported by the (or at least, our) URI encoding scheme.  We
         need to escape this character.  */

      /* First things first, copy all the good stuff that we haven't
         yet copied into our output buffer. */
      if (i - copied)
        svn_stringbuf_appendbytes(retstr, path + copied, 
                                  i - copied);
      
      /* Now, sprintf() in our escaped character, making sure our
         buffer is big enough to hold the '%' and two digits.  We cast
         the C to unsigned char here because the 'X' format character
         will be tempted to treat it as an unsigned int...which causes
         problem when messing with 0x80-0xFF chars.  We also need space
         for a null as sprintf will write one. */
      svn_stringbuf_ensure(retstr, retstr->len + 4);
      sprintf(retstr->data + retstr->len, "%%%02X", (unsigned char)c);
      retstr->len += 3;

      /* Finally, update our copy counter. */
      copied = i + 1;
    }

  /* If we didn't encode anything, we don't need to duplicate the string. */
  if (retstr->len == 0)
    return path;

  /* Anything left to copy? */
  if (i - copied)
    svn_stringbuf_appendbytes(retstr, path + copied, i - copied);

  /* retstr is null-terminated either by sprintf or the svn_stringbuf
     functions. */

  return retstr->data;
}

const char *
svn_path_uri_encode(const char *path, apr_pool_t *pool)
{
  const char *ret;

  ret = uri_escape(path, uri_char_validity, pool);

  /* Our interface guarantees a copy. */
  if (ret == path)
    return apr_pstrdup(pool, path);
  else
    return ret;
}

static const char iri_escape_chars[256] = {
  1, 1, 1, 1, 1, 1, 1, 1,  1, 1, 1, 1, 1, 1, 1, 1,
  1, 1, 1, 1, 1, 1, 1, 1,  1, 1, 1, 1, 1, 1, 1, 1,
  1, 1, 1, 1, 1, 1, 1, 1,  1, 1, 1, 1, 1, 1, 1, 1,
  1, 1, 1, 1, 1, 1, 1, 1,  1, 1, 1, 1, 1, 1, 1, 1,
  1, 1, 1, 1, 1, 1, 1, 1,  1, 1, 1, 1, 1, 1, 1, 1,
  1, 1, 1, 1, 1, 1, 1, 1,  1, 1, 1, 1, 1, 1, 1, 1,
  1, 1, 1, 1, 1, 1, 1, 1,  1, 1, 1, 1, 1, 1, 1, 1,
  1, 1, 1, 1, 1, 1, 1, 1,  1, 1, 1, 1, 1, 1, 1, 1,

  /* 128 */
  0, 0, 0, 0, 0, 0, 0, 0,  0, 0, 0, 0, 0, 0, 0, 0,
  0, 0, 0, 0, 0, 0, 0, 0,  0, 0, 0, 0, 0, 0, 0, 0,
  0, 0, 0, 0, 0, 0, 0, 0,  0, 0, 0, 0, 0, 0, 0, 0,
  0, 0, 0, 0, 0, 0, 0, 0,  0, 0, 0, 0, 0, 0, 0, 0,
  0, 0, 0, 0, 0, 0, 0, 0,  0, 0, 0, 0, 0, 0, 0, 0,
  0, 0, 0, 0, 0, 0, 0, 0,  0, 0, 0, 0, 0, 0, 0, 0,
  0, 0, 0, 0, 0, 0, 0, 0,  0, 0, 0, 0, 0, 0, 0, 0,
  0, 0, 0, 0, 0, 0, 0, 0,  0, 0, 0, 0, 0, 0, 0, 0
};

const char *
svn_path_uri_from_iri(const char *iri, apr_pool_t *pool)
{
  return uri_escape(iri, iri_escape_chars, pool);
}

const char uri_autoescape_chars[256] = {
  1, 1, 1, 1, 1, 1, 1, 1,  1, 1, 1, 1, 1, 1, 1, 1,
  1, 1, 1, 1, 1, 1, 1, 1,  1, 1, 1, 1, 1, 1, 1, 1,
  0, 1, 0, 1, 1, 1, 1, 1,  1, 1, 1, 1, 1, 1, 1, 1,
  1, 1, 1, 1, 1, 1, 1, 1,  1, 1, 1, 1, 0, 1, 0, 1,

  /* 64 */
  1, 1, 1, 1, 1, 1, 1, 1,  1, 1, 1, 1, 1, 1, 1, 1,
  1, 1, 1, 1, 1, 1, 1, 1,  1, 1, 1, 1, 0, 1, 0, 1,
  0, 1, 1, 1, 1, 1, 1, 1,  1, 1, 1, 1, 1, 1, 1, 1,
  1, 1, 1, 1, 1, 1, 1, 1,  1, 1, 1, 0, 0, 0, 1, 1,

  /* 128 */
  1, 1, 1, 1, 1, 1, 1, 1,  1, 1, 1, 1, 1, 1, 1, 1,
  1, 1, 1, 1, 1, 1, 1, 1,  1, 1, 1, 1, 1, 1, 1, 1,
  1, 1, 1, 1, 1, 1, 1, 1,  1, 1, 1, 1, 1, 1, 1, 1,
  1, 1, 1, 1, 1, 1, 1, 1,  1, 1, 1, 1, 1, 1, 1, 1,

  /* 192 */
  1, 1, 1, 1, 1, 1, 1, 1,  1, 1, 1, 1, 1, 1, 1, 1,
  1, 1, 1, 1, 1, 1, 1, 1,  1, 1, 1, 1, 1, 1, 1, 1,
  1, 1, 1, 1, 1, 1, 1, 1,  1, 1, 1, 1, 1, 1, 1, 1,
  1, 1, 1, 1, 1, 1, 1, 1,  1, 1, 1, 1, 1, 1, 1, 1,
};

const char *
svn_path_uri_autoescape(const char *uri, apr_pool_t *pool)
{
  return uri_escape(uri, uri_autoescape_chars, pool);
}

const char *
svn_path_uri_decode(const char *path, apr_pool_t *pool)
{
  svn_stringbuf_t *retstr;
  apr_size_t i;
  svn_boolean_t query_start = FALSE;

  retstr = svn_stringbuf_create("", pool);

  /* avoid repeated realloc */
  svn_stringbuf_ensure(retstr, strlen(path) + 1); 

  retstr->len = 0;
  for (i = 0; path[i]; i++)
    {
      char c = path[i];

      if (c == '?')
        {
          /* Mark the start of the query string, if it exists. */
          query_start = TRUE;
        }
      else if (c == '+' && query_start)
        {
          /* Only do this if we are into the query string.
           * RFC 2396, section 3.3  */
          c = ' ';
        }
      else if (c == '%' && apr_isxdigit(path[i + 1])
               && apr_isxdigit(path[i+2]))
        {
          char digitz[3];
          digitz[0] = path[++i];
          digitz[1] = path[++i];
          digitz[2] = '\0';
          c = (char)(strtol(digitz, NULL, 16));
        }

      retstr->data[retstr->len++] = c;
    }

  /* Null-terminate this bad-boy. */
  retstr->data[retstr->len] = 0;

  return retstr->data;
}


const char *
svn_path_url_add_component(const char *url,
                           const char *component,
                           apr_pool_t *pool)
{
  /* URL can have trailing '/' */
  url = svn_path_canonicalize(url, pool);

  return svn_path_join(url, svn_path_uri_encode(component, pool), pool);
}

svn_error_t *
svn_path_get_absolute(const char **pabsolute,
                      const char *relative,
                      apr_pool_t *pool)
{
  char *buffer;
  apr_status_t apr_err;
  const char *path_apr;

  SVN_ERR(svn_path_cstring_from_utf8
          (&path_apr, svn_path_canonicalize(relative, pool), pool));

  if (svn_path_is_url(path_apr))
    {
      buffer = apr_pstrdup(pool, path_apr);
    }
  else
    {
      apr_err = apr_filepath_merge(&buffer, NULL,
                                   path_apr,
                                   (APR_FILEPATH_NOTRELATIVE
                                    | APR_FILEPATH_TRUENAME),
                                   pool);

      if (apr_err)
        return svn_error_createf(SVN_ERR_BAD_FILENAME, NULL,
                                 _("Couldn't determine absolute path of '%s'"), 
                                 svn_path_local_style(relative, pool));
    }

  SVN_ERR(svn_path_cstring_to_utf8(pabsolute, buffer, pool));
  *pabsolute = svn_path_canonicalize(*pabsolute, pool);
  return SVN_NO_ERROR;
}


svn_error_t *
svn_path_split_if_file(const char *path,
                       const char **pdirectory,
                       const char **pfile,
                       apr_pool_t *pool)
{
  apr_finfo_t finfo;
  svn_error_t *err;

  /* assert (is_canonical (path, strlen (path)));  ### Expensive strlen */

  err = svn_io_stat(&finfo, path, APR_FINFO_TYPE, pool);
  if (err && ! APR_STATUS_IS_ENOENT(err->apr_err))
    return err;

  if (err || finfo.filetype == APR_REG)
    {
      if (err)
        svn_error_clear(err);
      svn_path_split(path, pdirectory, pfile, pool);
    }
  else if (finfo.filetype == APR_DIR)
    {
      *pdirectory = path;
      *pfile = SVN_EMPTY_PATH;
    }
  else 
    {
      return svn_error_createf(SVN_ERR_BAD_FILENAME, NULL,
                               _("'%s' is neither a file nor a directory name"),
                               svn_path_local_style(path, pool));
    }

  return SVN_NO_ERROR;
}


const char *
svn_path_canonicalize(const char *path, apr_pool_t *pool)
{
  char *canon, *dst;
  const char *src;
  apr_size_t seglen;
  apr_size_t canon_segments = 0;
  svn_boolean_t uri;

  dst = canon = apr_pcalloc(pool, strlen(path) + 1);

  /* Copy over the URI scheme if present. */
  src = skip_uri_scheme(path);
  if (src)
    {
      uri = TRUE;
      memcpy(dst, path, src - path);
      dst += (src - path);
    }
  else
    {
      uri = FALSE;
      src = path;
    }

  /* If this is an absolute path, then just copy over the initial
     separator character. */
  if (*src == '/')
    {
      *(dst++) = *(src++);

#if defined(WIN32) || defined(__CYGWIN__)
      /* On Windows permit two leading separator characters which means an
       * UNC path.  However, a double slash in a URI after the scheme is never
       * valid. */
      if (!uri && *src == '/')
        *(dst++) = *(src++);
#endif /* WIN32 or Cygwin */
      
    }

  while (*src)
    {
      /* Parse each segment, find the closing '/' */
      const char *next = src;
      while (*next && (*next != '/'))
        ++next;

      seglen = next - src;

      if (seglen == 0 || (seglen == 1 && src[0] == '.'))
        {
          /* Noop segment, so do nothing. */
        }
      else
        {
          /* An actual segment, append it to the destination path */
          if (*next)
            seglen++;
          memcpy(dst, src, seglen);
          dst += seglen;
          canon_segments++;
        }

      /* Skip over trailing slash to the next segment. */
      src = next;
      if (*src)
        src++;
    }

  /* Remove the trailing slash. */
  if ((canon_segments > 0 || uri) && *(dst - 1) == '/')
    dst--;
  
  *dst = '\0';

#if defined(WIN32) || defined(__CYGWIN__)
  /* Skip leading double slashes when there are less than 2
   * canon segments. UNC paths *MUST* have two segments. */
  if (canon_segments < 2 && canon[0] == '/' && canon[1] == '/')
    return canon + 1;
#endif /* WIN32 or Cygwin */

  return canon;
}



/** Get APR's internal path encoding. */
static svn_error_t *
get_path_encoding(svn_boolean_t *path_is_utf8, apr_pool_t *pool)
{
  apr_status_t apr_err;
  int encoding_style;

  apr_err = apr_filepath_encoding(&encoding_style, pool);
  if (apr_err)
    return svn_error_wrap_apr(apr_err,
                              _("Can't determine the native path encoding"));

  /* ### What to do about APR_FILEPATH_ENCODING_UNKNOWN?
     Well, for now we'll just punt to the svn_utf_ functions;
     those will at least do the ASCII-subset check. */
  *path_is_utf8 = (encoding_style == APR_FILEPATH_ENCODING_UTF8);
  return SVN_NO_ERROR;
}


svn_error_t *
svn_path_cstring_from_utf8(const char **path_apr,
                           const char *path_utf8,
                           apr_pool_t *pool)
{
  svn_boolean_t path_is_utf8;
  SVN_ERR(get_path_encoding(&path_is_utf8, pool));
  if (path_is_utf8)
    {
      *path_apr = apr_pstrdup(pool, path_utf8);
      return SVN_NO_ERROR;
    }
  else
    return svn_utf_cstring_from_utf8(path_apr, path_utf8, pool);
}


svn_error_t *
svn_path_cstring_to_utf8(const char **path_utf8,
                         const char *path_apr,
                         apr_pool_t *pool)
{
  svn_boolean_t path_is_utf8;
  SVN_ERR(get_path_encoding(&path_is_utf8, pool));
  if (path_is_utf8)
    {
      *path_utf8 = apr_pstrdup(pool, path_apr);
      return SVN_NO_ERROR;
    }
  else
    return svn_utf_cstring_to_utf8(path_utf8, path_apr, pool);
}

svn_error_t *
svn_path_check_valid(const char *path, apr_pool_t *pool)
{
  const char *c;

  for (c = path; *c; c++)
    {
      if (svn_ctype_iscntrl(*c))
        {
          return svn_error_createf
            (SVN_ERR_FS_PATH_SYNTAX, NULL,
             _("Invalid control character '0x%02x' in path '%s'"),
             *c,
             svn_path_local_style(path, pool));
        }
    }

  return SVN_NO_ERROR;
}