+GNUNET_STRINGS_data_to_string (const unsigned char *data,
+ size_t size,
+ char *out,
+ size_t out_size);
+
+
+/**
+ * Convert ASCII encoding back to data
+ * out_size must match exactly the size of the data before it was encoded.
+ *
+ * @param enc the encoding
+ * @param enclen number of characters in 'enc' (without 0-terminator, which can be missing)
+ * @param out location where to store the decoded data
+ * @param out_size sizeof the output buffer
+ * @return GNUNET_OK on success, GNUNET_SYSERR if result has the wrong encoding
+ */
+int
+GNUNET_STRINGS_string_to_data (const char *enc,
+ size_t enclen,
+ unsigned char *out,
+ size_t out_size);
+
+
+/**
+ * Parse a path that might be an URI.
+ *
+ * @param path path to parse. Must be NULL-terminated.
+ * @param scheme_part a pointer to 'char *' where a pointer to a string that
+ * represents the URI scheme will be stored. Can be NULL. The string is
+ * allocated by the function, and should be freed by GNUNET_free() when
+ * it is no longer needed.
+ * @param path_part a pointer to 'const char *' where a pointer to the path
+ * part of the URI will be stored. Can be NULL. Points to the same block
+ * of memory as 'path', and thus must not be freed. Might point to '\0',
+ * if path part is zero-length.
+ * @return GNUNET_YES if it's an URI, GNUNET_NO otherwise. If 'path' is not
+ * an URI, '* scheme_part' and '*path_part' will remain unchanged
+ * (if they weren't NULL).
+ */
+int
+GNUNET_STRINGS_parse_uri (const char *path,
+ char **scheme_part,
+ const char **path_part);
+
+
+/**
+ * Check whether filename is absolute or not, and if it's an URI
+ *
+ * @param filename filename to check
+ * @param can_be_uri GNUNET_YES to check for being URI, GNUNET_NO - to
+ * assume it's not URI
+ * @param r_is_uri a pointer to an int that is set to GNUNET_YES if 'filename'
+ * is URI and to GNUNET_NO otherwise. Can be NULL. If 'can_be_uri' is
+ * not GNUNET_YES, *r_is_uri is set to GNUNET_NO.
+ * @param r_uri_scheme a pointer to a char * that is set to a pointer to URI scheme.
+ * The string is allocated by the function, and should be freed with
+ * GNUNET_free (). Can be NULL.
+ * @return GNUNET_YES if 'filename' is absolute, GNUNET_NO otherwise.
+ */
+int
+GNUNET_STRINGS_path_is_absolute (const char *filename,
+ int can_be_uri,
+ int *r_is_uri,
+ char **r_uri_scheme);
+
+
+/**
+ * Flags for what we should check a file for.
+ */
+enum GNUNET_STRINGS_FilenameCheck
+{
+ /**
+ * Check that it exists.
+ */
+ GNUNET_STRINGS_CHECK_EXISTS = 0x00000001,
+
+ /**
+ * Check that it is a directory.
+ */
+ GNUNET_STRINGS_CHECK_IS_DIRECTORY = 0x00000002,
+
+ /**
+ * Check that it is a link.
+ */
+ GNUNET_STRINGS_CHECK_IS_LINK = 0x00000004,
+
+ /**
+ * Check that the path is an absolute path.
+ */
+ GNUNET_STRINGS_CHECK_IS_ABSOLUTE = 0x00000008
+};
+
+
+/**
+ * Perform checks on 'filename'. FIXME: some duplication with
+ * "GNUNET_DISK_"-APIs. We should unify those.
+ *
+ * @param filename file to check
+ * @param checks checks to perform
+ * @return GNUNET_YES if all checks pass, GNUNET_NO if at least one of them
+ * fails, GNUNET_SYSERR when a check can't be performed
+ */
+int
+GNUNET_STRINGS_check_filename (const char *filename,
+ enum GNUNET_STRINGS_FilenameCheck checks);
+
+
+/**
+ * Tries to convert 'zt_addr' string to an IPv6 address.
+ * The string is expected to have the format "[ABCD::01]:80".
+ *
+ * @param zt_addr 0-terminated string. May be mangled by the function.
+ * @param addrlen length of zt_addr (not counting 0-terminator).
+ * @param r_buf a buffer to fill. Initially gets filled with zeroes,
+ * then its sin6_port, sin6_family and sin6_addr are set appropriately.
+ * @return GNUNET_OK if conversion succeded. GNUNET_SYSERR otherwise, in which
+ * case the contents of r_buf are undefined.
+ */
+int
+GNUNET_STRINGS_to_address_ipv6 (const char *zt_addr,
+ uint16_t addrlen,
+ struct sockaddr_in6 *r_buf);
+
+
+/**
+ * Tries to convert 'zt_addr' string to an IPv4 address.
+ * The string is expected to have the format "1.2.3.4:80".
+ *
+ * @param zt_addr 0-terminated string. May be mangled by the function.
+ * @param addrlen length of zt_addr (not counting 0-terminator).
+ * @param r_buf a buffer to fill.
+ * @return GNUNET_OK if conversion succeded. GNUNET_SYSERR otherwise, in which case
+ * the contents of r_buf are undefined.
+ */
+int
+GNUNET_STRINGS_to_address_ipv4 (const char *zt_addr,
+ uint16_t addrlen,
+ struct sockaddr_in *r_buf);
+
+
+/**
+ * Tries to convert 'addr' string to an IP (v4 or v6) address.
+ * Will automatically decide whether to treat 'addr' as v4 or v6 address.
+ *
+ * @param addr a string, may not be 0-terminated.
+ * @param addrlen number of bytes in addr (if addr is 0-terminated,
+ * 0-terminator should not be counted towards addrlen).
+ * @param r_buf a buffer to fill.
+ * @return GNUNET_OK if conversion succeded. GNUNET_SYSERR otherwise, in which
+ * case the contents of r_buf are undefined.
+ */
+int
+GNUNET_STRINGS_to_address_ip (const char *addr,
+ uint16_t addrlen,
+ struct sockaddr_storage *r_buf);
+
+
+/**
+ * Returns utf-8 encoded arguments.
+ * Does nothing (returns a copy of argc and argv) on any platform
+ * other than W32.
+ * Returned argv has u8argv[u8argc] == NULL.
+ * Returned argv is a single memory block, and can be freed with a single
+ * GNUNET_free () call.
+ *
+ * @param argc argc (as given by main())
+ * @param argv argv (as given by main())
+ * @param u8argc a location to store new argc in (though it's th same as argc)
+ * @param u8argv a location to store new argv in
+ * @return GNUNET_OK on success, GNUNET_SYSERR on failure
+ */
+int
+GNUNET_STRINGS_get_utf8_args (int argc,
+ char *const *argv,
+ int *u8argc,
+ char *const **u8argv);
+